Vehicle control device

Abstract

The present invention addresses the problem of providing a vehicle control device that suppresses engine overheating. A vehicle control device is provided with: an acquisition unit that acquires position information of a vehicle in which an engine is mounted; a prediction unit that, on the basis of the position information, predicts whether or not the high-load operation of the engine continues for a predetermined time or longer; and a flow rate control unit that, when it is predicted that the high-load operation of the engine continues for the predetermined time or longer, increases the flow rate of the high-temperature cooling water flowing through the engine to the radiator compared to when it is not predicted that the high-load operation of the engine continues for the predetermined time or longer.

Description

Technical Field

[0001] This invention relates to a vehicle control device. Background Technology

[0002] When the temperature of the coolant becomes high or above a specified temperature due to continuous high-load operation of the engine, the flow rate of the coolant flowing to the radiator is increased (for example, see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2006-105105 Summary of the Invention

[0004] In the aforementioned techniques, the flow rate of coolant flowing to the radiator is increased after the engine has reached a high temperature. Therefore, it is possible that the engine temperature rise may not be sufficiently suppressed, leading to engine overheating.

[0005] Therefore, the object of the present invention is to provide a vehicle control device that suppresses engine overheating.

[0006] The above objective can be achieved by a vehicle control device having the following components: an acquisition unit that acquires the location information of a vehicle equipped with an engine; a prediction unit that predicts, based on the location information, whether the engine will continue to operate at high load for a specified time or more; and a flow control unit that, when it is predicted that the engine will continue to operate at high load for a specified time or more, increases the flow rate of the high-temperature coolant flowing through the engine to the radiator compared to when it is not predicted that the engine will continue to operate at high load for a specified time or more.

[0007] It may also include a heat exchange control unit that, when it is predicted that the high-load operation of the engine will continue for more than the specified time, further increases the heat exchange between the air conditioning refrigerant and the low-temperature cooling water in the heat exchanger that supplies the air conditioning refrigerant and the low-temperature cooling water flowing through the intercooler and turbocharger of the engine.

[0008] The heat exchanger may also include: a first passage for the flow of the low-temperature cooling water; a second passage for the flow of the air conditioning refrigerant; a third passage for the flow of the air conditioning refrigerant and located closer to the first passage than the second passage; and a switching valve that directs the air conditioning refrigerant to flow into the second passage or the third passage.

[0009] The heat exchange quantity control unit increases the heat exchange quantity by controlling the switching valve to allow the air conditioning refrigerant to flow into the second passage when it is not predicted that the engine will continue to operate at high load for more than the specified time, and by controlling the switching valve to allow the air conditioning refrigerant to flow into the third passage when it is predicted that the engine will continue to operate at high load for more than the specified time.

[0010] It may also include an ignition timing control unit that, when it is predicted that the engine will operate under high load for a specified time or longer, adjusts the ignition timing advance angle of the engine more precisely than when it is not predicted that the engine will operate under high load for a specified time or longer.

[0011] The prediction unit can also predict that the engine will operate at high load for more than the specified time, provided that the location information indicates that the vehicle is located on a racetrack or gymkhana track.

[0012] Invention Effects

[0013] According to the present invention, a vehicle control device that suppresses engine overheating can be provided. Attached Figure Description

[0014] Figure 1 It is a schematic diagram of the vehicle's structure.

[0015] Figure 2 This is a schematic diagram of the high-temperature cooling circuit.

[0016] Figure 3 It is a graph showing the opening ratios of the flow path adjusted by the multi-function valve.

[0017] Figure 4 This is a schematic diagram of the low-temperature cooling circuit and the air conditioning circuit.

[0018] Figure 5 This is a flowchart illustrating overheat suppression control performed by the ECU.

[0019] Figure 6 It is a graph showing the relationship between ignition timing and the temperature of the hot coolant just discharged from the engine. Detailed Implementation

[0020] [General Vehicle Structure]

[0021] Figure 1This is a schematic structural diagram of vehicle 100. Vehicle 100 includes: engine 1; intake passage 3; exhaust passage 4; turbocharger 5; intercooler 6; catalyst 7a; filter 7b; bypass passage 8; wastegate valve (hereinafter referred to as WGV) 9; automatic transmission 21; differential gear 23; wheels 25; and electronic control unit (ECU) 30. Engine 1 is a gasoline engine. The driving force of engine 1 is transmitted to wheels 25 via automatic transmission 21 and differential gear 23. Vehicle 100 is an engine vehicle with engine 1 as its drive source. However, it can also be a hybrid vehicle that has an electric motor as a drive source in addition to engine 1.

[0022] Engine 1 has four cylinders 2, but the number of cylinders is not limited to this. Each cylinder 2 is equipped with a fuel injection valve 2a and a spark plug 2b. An intake passage 3 and an exhaust passage 4 are connected to engine 1. A compressor 5b of a turbocharger 5 is located midway through the intake passage 3. A turbine 5a of the turbocharger 5 is located midway through the exhaust passage 4. The turbine 5a and the compressor 5b are coaxially connected via a shaft. The turbocharger 5 pressurizes the intake air of engine 1.

[0023] A bypass passage 8, which bypasses the turbine 5a, and a WGV9, which opens and closes the bypass passage 8, are provided midway through the exhaust passage 4. The opening degree of the WGV9 is adjusted by an electric actuator 9a that drives the WGV9. The opening degree of the WGV9 is controlled by feedback from the ECU 30 to ensure that the boost pressure reaches the target boost pressure determined based on the operating state of the engine 1. The ECU 30 outputs command values ​​to the electric actuator 9a to control the opening degree of the WGV9. The WGV9 is a normally closed type, where the electric actuator 9a is fully closed when not energized.

[0024] In the intake passage 3, an intercooler 6 for cooling the intake air is disposed downstream of the compressor 5b. In the intake passage 3, a throttle valve 3a for adjusting the amount of air intaked into the engine 1 is disposed downstream of the intercooler 6.

[0025] In the exhaust passage 4, a catalyst 7a for purifying exhaust gas and a filter 7b for capturing exhaust particulate matter are disposed downstream of the turbine 5a. The filter 7b is disposed further downstream of the catalyst 7a. The catalyst 7a is, for example, a catalyst metal containing platinum (Pt), palladium (Pd), or rhodium (Rh), and has oxygen storage capacity, purifying NOx, HC, and CO. The filter 7b is a porous ceramic structure.

[0026] ECU 30 includes a Central Processing Unit (CPU), Read Only Memory (ROM), and Random Access Memory (RAM). ECU 30 controls engine 1 based on a control program pre-stored in the ROM, using information from sensors or other information pre-stored in the ROM. ECU 30 is an example of a vehicle control device. ECU 30 achieves overheat suppression control (described later) by functionally implementing an acquisition unit, a prediction unit, a flow control unit, a heat exchange control unit, and an ignition timing control unit.

[0027] The ECU 30 controls the operating state of the engine 1 based on detection signals from various sensors, including the crankshaft angle sensor 11, the air flow meter 12, the air-fuel ratio sensor 13, and the throttle opening sensor 14. The crankshaft angle sensor 11 detects the rotation angle of the crankshaft of the engine 1. The air flow meter 12 detects the amount of air drawn into the intake passage 3. The air-fuel ratio sensor 13 detects the air-fuel ratio of the exhaust gas discharged from the engine 1. The throttle opening sensor 14 detects the throttle opening, which is the amount of input to the accelerator pedal.

[0028] The ECU 30 monitors the engine speed or load of the engine 1 based on the output signals from various sensors. Based on this monitored operating state, the ECU 30 outputs command signals to various drive circuits connected to its output ports. Examples of controls performed by the ECU 30 include throttle control (adjusting the opening of the throttle valve 3a), fuel injection control (adjusting the injection quantity of the fuel injection valve 2a), and ignition timing control (adjusting the ignition timing of the spark plug 2b).

[0029] Furthermore, a data communication module (DCM) 32, acting as a wireless communication device, is connected to 30. The DCM 32 obtains information from the driver's mobile terminal (e.g., a smartphone) 34 via a communication network. Specifically, the mobile terminal 34 has a built-in GPS, and the DCM 32 obtains the location information of the mobile terminal 34 via the communication network. Thus, 30 obtains the current location information of the vehicle 100. Furthermore, the DCM 32 obtains map information about the vicinity of the vehicle 100's current location via the network. Alternatively, the location information of the vehicle 100 or the surrounding map information obtained by 30 can be obtained, for example, from a car navigation system equipped with GPS.

[0030] [Simplified structure of the high-temperature cooling circuit]

[0031] Figure 2This is a schematic diagram of the high-temperature cooling circuit 40. In the high-temperature cooling circuit 40, heat exchange occurs between the engine 1 and the high-temperature coolant flowing within the engine 1 to cool the engine 1. The high-temperature cooling circuit 40 includes a radiator 51, a reservoir 52, a heater core 53, an automatic transmission fluid (ATF) cooler 55, a throttle body water jacket 56, a water pump 57, an oil cooler 58a, an exhaust cooling section 58b, and an air intake 59.

[0032] Water pump 57 is a mechanical pump that delivers high-temperature cooling water via the rotational power of engine 1. A portion of the high-temperature cooling water flows from water pump 57 through flow path 48 to the cylinder block 1B, cylinder head 1A, and exhaust cooling section 58b of engine 1. Additionally, a portion of the high-temperature cooling water flows from water pump 57 through flow path 47 to oil cooler 58a and then to exhaust cooling section 58b. High-temperature cooling water flows from exhaust cooling section 58b through flow path 44 to multi-function valve 50. Multi-function valve 50 is a four-way valve connected to flow paths 41, 43, 44, and 45. The opening degree of flow paths 41, 43, and 45 is changed according to the rotation angle position of the rotor of multi-function valve 50 (described later). The rotor of multi-function valve 50 is controlled by ECU 30. Details will be described later.

[0033] Flow path 41 connects the multi-function valve 50 and the air inlet 59, with a radiator 51 installed in the middle. Heat exchange occurs between the high-temperature cooling water and the outside air in the radiator 51, promoting heat dissipation from the high-temperature cooling water. The high-temperature cooling water discharged from the radiator 51 is supplied to the air inlet 59 via flow path 41.

[0034] A flow path 42 is provided, which branches off upstream of the radiator 51 and rejoins the flow path 41 downstream of the radiator 51. A liquid storage tank 52 is provided in the middle of the flow path 42.

[0035] The flow path 46 connects to the multi-function valve 50 and the air intake 59, and a throttle body water jacket 56 is installed in the middle of the path. The throttle body water jacket 56 is located inside the throttle body valve 3a. In the throttle body water jacket 56, heat exchange occurs between the high-temperature cooling water and the throttle body valve 3a, thereby cooling the throttle body valve 3a.

[0036] The portion of flow path 43 and flow path 46 upstream of the throttle body water jacket 56 is connected to the air intake 59. A heater core 53 is installed in flow path 43. Heat exchange occurs between high-temperature cooling water and the air used for vehicle heating in heater core 53.

[0037] The flow path 45 is connected to the multi-function valve 50 and the air inlet 59, with an ATF cooler 55 located in between. In the ATF cooler 55, the ATF used for the operation, lubrication and cooling of the automatic transmission is cooled by heat exchange between the ATF and high-temperature coolant.

[0038] As described above, the high-temperature cooling water passing through the radiator 51, reservoir 52, heater core 53, and ATF cooler 55 is supplied to the air intake 59. The high-temperature cooling water supplied to the air intake 59 is then supplied to the engine 1 again via the water pump 57.

[0039] Figure 3 This is a graph showing the opening ratios of flow paths 41, 46, and 45, adjusted by the multi-function valve 50. The multi-function valve 50 has a rotatable rotor, and the opening ratio of each flow path is adjusted according to the rotation angle of the rotor. Figure 3 The diagram shows the range of angles from αS to -βS, representing the angles within which the rotor can rotate. The angle used as the reference for rotor rotation is set to 0 degrees.

[0040] At angle 0 degrees, flow paths 41, 46, and 45 are all fully closed. Between angles α1 and α2, flow path 46 changes from fully closed to fully open. Between angles α3 and α4, flow path 45 changes from fully closed to fully open. Between angles α5 and α6, flow path 41 changes from fully closed to fully open. Between angles α6 and αS, flow paths 41, 46, and 45 are all fully open. Between angles (-β1) and (-β2), flow path 45 changes from fully closed to fully open. Between angles (-β3) and (-β4), flow path 41 changes from fully closed to fully open. Between angles (-β4) and (-βS), flow paths 41 and 45 are fully open, and flow path 46 is fully closed.

[0041] [Brief Structure of Low-Temperature Cooling Circuit and Air Conditioning Circuit]

[0042] Figure 4This is a schematic diagram of the low-temperature cooling circuit 60 and the air conditioning circuit 80. The low-temperature cooling circuit 60 includes an intercooler 6, a low-temperature radiator 71, a liquid receiver 72, a water pump 77, and a cooler 90. The water pump 77 is an electric pump controlled by the ECU 30. Through the water pump 77, low-temperature cooling water flows sequentially through flow path 61 to the intercooler 6, the low-temperature radiator 71, the liquid receiver 72, and the cooler 90. In the low-temperature radiator 71, heat exchange occurs between the low-temperature cooling water and the outside air, promoting heat dissipation. Flow path 62 and flow path 61 are connected between the water pump 77 and the cooler 90, and between flow path 61 and the intercooler 6 and the low-temperature radiator 71. A booster 5 is installed in flow path 62. The cooler 90 has a first passage 94 connected to flow path 61. Details about the cooler 90 will be described later. In addition, the temperature of the low-temperature cooling water flowing through the low-temperature cooling circuit 60 is lower than the temperature of the high-temperature cooling water flowing through the high-temperature cooling circuit 40.

[0043] Air conditioning circuit 80 includes a cooler 90, an evaporator 95, a compressor 96, and a condenser 97. Air conditioning circuit 80 constitutes a refrigeration cycle. Air conditioning refrigerant flows sequentially through flow path 81 to the cooler 90, evaporator 95, compressor 96, and condenser 97. The evaporator 95 absorbs heat from the air surrounding it, causing the refrigerant to evaporate. The compressor 96 adiabatically compresses the low-temperature, low-pressure, primarily gaseous refrigerant flowing from the evaporator 95, transforming it into a high-temperature, high-pressure, primarily gaseous state. The condenser 97 condenses the refrigerant into a liquid state by exchanging heat with the outside air. The cooler 90 is a heat exchanger that facilitates heat exchange between the refrigerant flowing through the cooler 90 and the low-temperature cooling water flowing through the first passage 94 of the cooler 90. The temperature of the refrigerant flowing through the cooler 90 is lower than the temperature of the low-temperature cooling water flowing through the cooler 90. Therefore, the temperature of the low-temperature cooling water decreases, and the intercooler 6 or turbocharger 5 in the low-temperature cooling circuit 60 is cooled.

[0044] In addition to the first passage 94 described above, the cooler 90 also includes a second passage 91, a third passage 92, and a switching valve 93. The flow path 81 connects to both the second and third passages 91 and 92. Therefore, air conditioning refrigerant can flow through the second and third passages 91 and 92. The switching valve 93 is located at the connection between the second and third passages 91 and 92. The switching valve 93 is a solenoid valve that fully opens one of the second and third passages 91 and 92 while fully closing the other. The switching valve 93 is controlled by 30. The third passage 92 flows closer to the first passage 94 than the second passage 91. Therefore, compared to the case where the air conditioning refrigerant flows through the second passage 91, the case where the air conditioning refrigerant flows through the third passage 92 promotes heat exchange with the low-temperature cooling water, causing the low-temperature cooling water to become cold.

[0045] [Overheating Suppression Control]

[0046] Next, the overheat suppression control performed by ECU30 will be explained. Figure 5 This is a flowchart illustrating the overheat suppression control performed by ECU 30. ECU 30 obtains the position information of vehicle 100 using the method described above (step S1). Step S1 is an example of the processing performed by the acquisition unit.

[0047] Next, the ECU 30 predicts whether the high-load operation of engine 1 will continue for a predetermined time or longer based on the location information (step S2). For example, if the current position of vehicle 100 indicates a racetrack or gymkhana course based on the location information, it is determined to be "yes" in step S2. Furthermore, if the vehicle 100 continues uphill for a predetermined distance or at a predetermined inclination angle within a predetermined range of its direction of travel, it is also determined to be "yes" in step S2. Here, the predetermined time refers to the time during which the engine 1 may overheat due to continuous high-load operation. If the result in step S2 is "no," the control process ends. Step S2 is an example of the processing performed by the prediction unit.

[0048] If "yes" is true in step S2, ECU 30 executes a process to increase the radiator flow rate of engine 1 (step S3). This process increases the flow rate of high-temperature coolant to radiator 51 when "yes" is true in step S2, compared to when "no" is true in step S2. Specifically, this is achieved by adjusting... Figure 3 The rotor angle of the multi-function valve 50 shown increases the flow rate of high-temperature cooling water to the radiator 51. For example, the rotor of the multi-function valve 50 is controlled between angles (-β4) and (-βS). As a result, flow paths 41 and 45 are fully open, and flow path 46 is fully closed. Therefore, high-temperature cooling water flows to the radiator 51 and the ATF cooler 55, but not to the heater core 53 and the throttle body water jacket 56. Figure 2 This indicates a state where high-temperature coolant flows to radiator 51 and ATF cooler 55, but not to heater core 53 and throttle body water jacket 56. In this case, the flow rate of high-temperature coolant flowing to radiator 51 reaches its maximum. In radiator 51, the heat dissipation of the high-temperature coolant reaches its maximum, thereby improving the cooling performance of engine 1. Therefore, overheating of engine 1 is suppressed.

[0049] Furthermore, between angles α6 and αS, flow path 41 is fully open, as are flow paths 45 and 46. Therefore, when the rotor of the multi-function valve 50 is controlled between angles (-β4) and (-βS), the flow rate of the high-temperature cooling water flowing to the radiator 51 is greater. Step S3 is an example of the processing performed by the flow control unit.

[0050] Next, ECU30 performs a heat exchange capacity increase process (step S4). The heat exchange capacity increase process is, when step S2 is "yes," compared to when step S2 is "no," that increases the heat exchange capacity between the air conditioning refrigerant and the low-temperature cooling water in the cooler 90. Specifically, this is achieved by controlling... Figure 4 The switching valve 93 shown closes the second passage 91 completely and opens the third passage 92 completely. As a result, the refrigerant flows through a position closer to the first passage 94 than the low-temperature cooling water flows through, increasing the heat exchange between the refrigerant and the low-temperature cooling water. Figure 4 This indicates that the low-temperature cooling water flows through the third passage 92 and does not flow into the second passage 91. As a result, the low-temperature cooling water reaches an even lower temperature, and the intercooler 6 and turbocharger 5 are adequately cooled. This effectively reduces the temperature of the intake air pressurized by the turbocharger 5, thereby improving the cooling performance of the engine 1. Therefore, overheating of the engine 1 is suppressed.

[0051] Next, ECU30 performs ignition timing delay processing (step S5). Ignition timing delay processing is the processing of the ignition timing advance angle based on the spark plug 2b of engine 1, compared to the case where it is "no" in step S2 if it is "yes". Figure 6 This is a graph showing the relationship between ignition timing and the temperature of the hot coolant just discharged from engine 1. For example... Figure 6 As shown, the closer the ignition timing is to the advance angle side, the lower the temperature of the high-temperature coolant, that is, the lower the heat generation of engine 1. Therefore, overheating of engine 1 is suppressed. Step S5 is an example of the processing performed by the ignition timing control unit.

[0052] As described above, when it is predicted that the engine 1 will operate under high load for a specified period of time or longer based on the location information of the vehicle 100, the above-described process is performed. Therefore, overheating of the engine 1 can be effectively suppressed.

[0053] Vehicle 100 can also be a hybrid vehicle that has a motor as a driving power source in addition to engine 1.

[0054] The embodiments of the present invention have been described in detail above, but the present invention is not limited to this specific embodiment. Various modifications and alterations can be made within the scope of the spirit of the present invention as set forth in the claims.

[0055] Symbol Explanation

[0056] 1-Engine, 2b-Spark plug, 5-Turbocharger, 6-Intercooler, 30-ECU (Vehicle Control Unit, Acquisition Unit, Prediction Unit, Flow Control Unit, Heat Exchange Control Unit, Ignition Timing Control Unit), 51-Radiator, 90-Cooler (Heat Exchanger), 91-Second Passage, 92-Third Passage, 93-Switching Valve, 94-First Passage, 100-Vehicle.

Claims

1. A vehicle control device, characterized in that, have: The acquisition unit acquires the location information of vehicles equipped with engines; The prediction unit predicts, based on the location information, whether the high-load operation of the engine will continue for a specified time or longer. and The flow control unit, when predicting that the engine will operate at high load for more than the specified time, increases the flow rate of the high-temperature cooling water flowing through the engine to the radiator more than when it does not predict that the engine will operate at high load for more than the specified time.

2. The vehicle control device according to claim 1, characterized in that, It includes a heat exchange control unit that, when it is predicted that the engine will operate at high load for a specified time or longer, increases the amount of heat exchange between the air conditioning refrigerant and the low-temperature cooling water flowing through the intercooler and turbocharger of the engine.

3. The vehicle control device according to claim 2, characterized in that, The heat exchanger includes: a first passage for the flow of the low-temperature cooling water; a second passage for the flow of the air conditioning refrigerant; a third passage for the flow of the air conditioning refrigerant and located closer to the first passage than the second passage; and a switching valve that directs the flow of the air conditioning refrigerant to either the second or the third passage. The heat exchange quantity control unit increases the heat exchange quantity by controlling the switching valve to allow the air conditioning refrigerant to flow into the second passage when it is not predicted that the engine will continue to operate at high load for more than the specified time, and by controlling the switching valve to allow the air conditioning refrigerant to flow into the third passage when it is predicted that the engine will continue to operate at high load for more than the specified time.

4. The vehicle control device according to claim 3, characterized in that, It includes an ignition timing control unit that, when it is predicted that the engine will operate under high load for a specified time or longer, adjusts the ignition timing advance angle of the engine more precisely than when it is not predicted that the engine will operate under high load for a specified time or longer.

5. The vehicle control device according to any one of claims 1 to 4, characterized in that, The prediction unit predicts that the engine will continue to operate at high load for more than the specified time, provided that the location information indicates that the vehicle is located on a racetrack or gymkhana track.

Images