Vehicle control device

Abstract

To provide a vehicle control device capable of securing stability of combustion of mixed gas.SOLUTION: In a vehicle which comprises an engine having an engine body and an intake passage and a transmission transmitting output rotation of the engine to wheels while changing a rotation speed, a vehicle control device has: a transmission control section which is capable of changing a stage of the transmission in accordance with a predetermined transmission schedule; a condensate water estimation section which estimates an accumulated condensate water amount, an amount of condensate water accumulated in the intake passage; and a determination section which determines whether or not the accumulated condensate water amount estimated with the condensate water estimation section is equal to or larger than a predetermined determination amount. When the determination section determines that the accumulated condensate water amount is equal to or larger than the determination amount, the vehicle control device causes the transmission control section to execute forced shift up control to increase the stage of the transmission regardless of the transmission schedule.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a control device for a vehicle equipped with an engine and a transmission. [Background technology]

[0002] In an engine mounted on a vehicle, water may condense and accumulate in the intake passage when the vehicle is stopped. In response to this, for example, Patent Document 1 discloses a vehicle equipped with an engine and an automatic transmission, in which the automatic transmission is placed in a neutral state when the vehicle is stopped, and then the engine speed is temporarily increased in order to remove water that has accumulated in the intake passage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6155951 Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration of Patent Document 1, water accumulated in the intake passage is removed from the intake passage by being introduced into the engine body. Therefore, with this configuration, when the engine is started with a large amount of water accumulated in the intake passage, the accumulated large amount of water may suddenly flow into the combustion chamber, causing instability in the combustion of the air-fuel mixture in the combustion chamber. As such, the configuration of Patent Document 1 leaves room for improvement in terms of ensuring the stability of the combustion of the air-fuel mixture.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide a vehicle control device that can ensure stable combustion of an air-fuel mixture. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present invention provides a control device for controlling a vehicle equipped with an engine having an engine body and an intake passage through which intake air introduced into the engine body flows, and a transmission that transmits engine output rotation to wheels while changing the speed, the control device comprising: a transmission control unit that can change the gear position of the transmission in accordance with a preset gear change schedule; a condensed water amount estimation unit that estimates an amount of accumulated condensed water, which is the amount of condensed water accumulated in the intake passage; and a determination unit that determines whether the amount of accumulated condensed water estimated by the condensed water amount estimation unit is equal to or greater than a predetermined determination amount, and the transmission control unit determines whether the amount of accumulated condensed water is equal to or greater than the determination amount by the determination unit. And the engine speed is equal to or greater than the predetermined threshold speed. In this case, a forced upshift control is performed to increase the stage of the transmission regardless of the shift schedule. death , When the determining unit determines that the amount of accumulated condensed water is equal to or greater than the determination amount and the engine speed is less than the determination speed, the gear position of the transmission is changed in accordance with the shift schedule. It is characterized by:

[0007] With this configuration, when the amount of condensed water accumulated in the intake passage is equal to or greater than a threshold amount and there is a risk that a large amount of condensed water will flow from the intake passage into the engine body, an upshift is performed to switch the transmission to a higher gear. When the upshift is performed, the engine speed decreases. As the engine speed decreases, the flow rate of intake air from the intake passage to the engine body decreases, and the amount of condensed water flowing into the engine body along with the intake air also decreases. Therefore, with this configuration, when there is a risk that a large amount of condensed water will flow from the intake passage into the engine body, the amount of condensed water flowing into the engine body can be reliably reduced. This also prevents the inflow of condensed water from destabilizing the combustion of the air-fuel mixture in the combustion chamber.

[0008] Moreover, The transmission control unit performs the forced upshift control when the amount of accumulated condensed water is equal to or greater than the determination amount and the engine speed is equal to or greater than a predetermined determination speed, and changes the gear position of the transmission according to the shift schedule when the amount of accumulated condensed water is equal to or greater than the determination amount and the engine speed is less than the determination speed. do.

[0009] That is,When the amount of accumulated condensed water is equal to or greater than the threshold amount and the engine speed is equal to or greater than the threshold speed, resulting in a large intake air flow rate and a large amount of condensed water likely to flow into the engine body along with the intake air, the forced upshift control is implemented to perform an upshift. This reliably prevents a large amount of condensed water from flowing into the engine body. Furthermore, even if the amount of accumulated condensed water is equal to or greater than the threshold amount, when the engine speed is less than the threshold speed and the amount of condensed water flowing into the engine body is kept low, the transmission is controlled according to the shift schedule. This prevents a large amount of condensed water from flowing into the engine body while minimizing the chance of the driver switching gears unexpectedly, ensuring smooth driving.

[0010] In the above-described configuration, preferably, a torque control unit is provided that controls engine torque, and the torque control unit reduces the engine torque when the amount of accumulated condensed water is equal to or greater than the determination amount and the engine speed is equal to or greater than a predetermined second determination speed that is higher than the determination speed (see claim 1). 2 ).

[0011] With this configuration, when the engine speed is very high, equal to or higher than the second threshold speed, and it is highly likely that the gear is at or near the highest gear, that is, when it is highly likely that it will be difficult to reduce the engine speed by further upshifting, the engine torque is reduced, thereby reducing the engine speed. Therefore, in cases where a large amount of condensed water is likely to flow into the engine body, it is possible to more reliably reduce the engine speed and more reliably prevent a large amount of condensed water from flowing into the engine body.

[0012] In the above configuration, preferably, the torque control unit reduces engine torque when the engine speed becomes equal to or higher than the second determination speed after the forced upshift control is performed, and prohibits reduction of engine torque when the engine speed becomes equal to or higher than the second determination speed while the forced upshift control is not being performed (see claim 3 ).

[0013] In this configuration, when the engine speed reaches or exceeds the second threshold speed without the forced upshift control being performed, that is, when the engine speed rises suddenly in response to a request from the driver, such as sudden acceleration, a decrease in engine torque is prohibited, thereby enabling driving that meets the driver's needs.

[0014] In the above-described configuration, preferably, a condensed water state estimation unit is provided for estimating a state of condensed water accumulated in the intake passage, and the transmission control unit is configured to determine whether the amount of accumulated condensed water is equal to or greater than the determination amount. And the engine speed is equal to or higher than a predetermined judgment speed. When the condensed water state estimation unit estimates that at least a part of the condensed water is liquid, the forced upshift control is executed (see claims 4 ).

[0015] According to this configuration, the forced upshift control is implemented when at least a portion of the condensed water accumulated in the intake passage is liquid and the condensed water is likely to be introduced into the engine body. This reliably prevents the condensed water from being introduced into the engine body. Furthermore, by not implementing the forced upshift control when all of the condensed water is solid, that is, when the condensed water is in the form of ice and adheres to the wall surface of the intake passage and is not likely to flow into the engine body, the chances of an upshift occurring at a timing unexpected by the driver are reduced.

[0016] In the above configuration, it is preferable to further include a water temperature sensor that detects a coolant temperature, which is the temperature of the coolant that cools the engine body, and an intake air temperature sensor that detects an intake air temperature, which is the temperature of the intake air flowing through the intake passage, and the condensed water state estimation unit determines the state of the condensed water based on the detected values ​​of the water temperature sensor and the intake air temperature sensor (see claim 5 ).

[0017] The temperature of the condensed water accumulated in the intake passage changes depending on the temperature of the intake air and the temperature of the engine body. Therefore, with the above configuration, the state of the condensed water can be determined with high accuracy. [Effects of the Invention]

[0018] As described above, the vehicle control device of the present invention can ensure the stability of the combustion of the air-fuel mixture. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a system diagram showing a schematic configuration of a vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic perspective view of an intake manifold. [Figure 3] FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 2. [Figure 4] FIG. 2 is a block diagram showing a control system of a vehicle. [Figure 5] 4 is a flowchart showing a procedure for condensed water inflow suppression control. [Figure 6] 4 is a flowchart showing a procedure for estimating the amount of intake manifold condensed water. DETAILED DESCRIPTION OF THE INVENTION

[0020] Fig. 1 is a system diagram showing a schematic configuration of a vehicle V to which a control device according to an embodiment of the present invention is applied. Fig. 2 is a schematic perspective view of an intake manifold 37 of an engine 1, which will be described later. Fig. 3 is a schematic cross-sectional view taken along line III-III in Fig. 2.

[0021] A vehicle V according to this embodiment has an engine 1 as a driving source for traveling. In this embodiment, the engine 1 is an in-line four-cylinder engine having four cylinders 4 arranged in series in a direction perpendicular to the plane of FIG. 1 . The vehicle V is provided with a transmission 60 that transmits the output rotation of the engine 1 to wheels 70 while changing the speed. The transmission 60 is a multi-speed transmission 60 having a plurality of gear stages (stages). In this embodiment, the transmission 60 has eight stages (eight gears), that is, an eight-speed (eight-speed) transmission. The transmission 60 is an automatic transmission, and the stages are changed by a controller 100, which will be described later.

[0022] (Engine configuration) The engine 1 comprises a four-stroke engine body 10 having a plurality of cylinders 4, an intake passage 30 through which intake air introduced into the engine body 10 flows, and an exhaust passage 40 through which exhaust gas discharged from the engine body 10 flows.

[0023] The engine body 10 has four cylinders 4 (only one of which is shown in FIG. 1) lined up in a direction perpendicular to the plane of the paper on which FIG. 1 is drawn. The engine body 10 includes a cylinder block 2 in which the multiple cylinders 4 are formed, and a cylinder head 3 attached to the upper surface of the cylinder block 2. A piston 5 is housed in each cylinder 4 so that it can slide back and forth. Each piston 5 is connected to a crankshaft 7 via a connecting rod. The crankshaft 7 rotates around its central axis in response to the reciprocating motion of the piston 5. A combustion chamber 6 is defined above each piston 5.

[0024] A crank angle sensor SN1 and a water temperature sensor SN5 are attached to the cylinder block 2. The crank angle sensor SN1 detects the rotation angle of the crankshaft 7, i.e., the engine speed. The water temperature sensor SN5 detects the temperature of the cooling water flowing inside the cylinder block 2 and the cylinder head 3. In other words, the cylinder block 2 and the cylinder head 3 are formed with a water jacket W (Fig. 3) through which the cooling water flows, and the water temperature sensor SN 5 detects the temperature of the cooling water flowing through the water jacket W.

[0025] The cylinder head 3 has intake ports 8 and exhaust ports 6 which communicate with the combustion chambers 6, respectively. The cylinder head 3 is formed with intake valves 18 for opening and closing each intake port 8, and exhaust valves 19 for opening and closing each exhaust port 9. The intake valves 18 and exhaust valves 19 are driven to open and close by a valve mechanism provided in the cylinder head 3. The cylinder head 3 is fitted with one injector 16 for injecting fuel supplied from a fuel tank (not shown) via a fuel pipe 17 into the combustion chamber 6, and one spark plug 15 for igniting the fuel-air mixture in the combustion chamber 6.

[0026] A crankcase 11 that houses the crankshaft 7 is fixed to the lower surface of the cylinder block 2. An oil pan 21 is fixed to the lower surface of the crankcase 11.

[0027] The oil pan 21 stores lubricating oil for lubricating various parts of the engine body 10. The lubricating oil in the oil pan 21 is pressure-fed to various parts by an oil pump 23 via a lubricating oil passage 22. The lubricating oil passage 22 is provided with an oil temperature sensor SN6 that detects the oil temperature, which is the temperature of the lubricating oil flowing inside the lubricating oil passage 22, i.e., the lubricating oil in the oil pan 21, and an oil pressure sensor SN7 that detects the oil pressure, which is the pressure of the lubricating oil.

[0028] The intake passage 30 is connected to one side of the engine body 10 so as to communicate with each intake port 8. The intake passage 30 has, in order from the upstream side, an air cleaner 31, a throttle valve body 32, a surge tank 36, and an intake manifold 37.

[0029] The air cleaner 31 removes foreign matter from the intake air. The throttle valve body 32 has a valve case 34 that defines a passage through which the intake air flows, a throttle valve 33 that opens and closes the passage inside the valve case 34, i.e., the intake passage 30, to change the flow rate of intake air flowing through the passage into the combustion chamber 6, and a throttle motor 35 that drives the throttle valve 33 to open and close. The surge tank 36 is a tank with a predetermined space inside. The intake manifold 37 distributes the intake air in the surge tank 36 to each combustion chamber 6. The intake manifold 37 has multiple independent intake passages 37A that individually connect the surge tank 36 to each cylinder 4. In this embodiment, the intake manifold 37 has four independent intake passages 37A.

[0030] 2 and 3, the four independent intake passages 37A are aligned in the direction in which the cylinders 4 are aligned (cylinder alignment direction). The surge tank 36 is located below the openings of the intake ports 8 on the outer surface of the engine body 10. The intake manifold 37 (each independent intake passage 37A) extends upward from the surge tank 36 while curving.

[0031] The intake passage 30 is provided with an air flow sensor SN2 that detects the intake air volume, which is the flow rate of the intake air flowing through the passage; an intake manifold pressure sensor SN3 that detects the intake air pressure, which is the pressure of the intake air; and an intake manifold temperature sensor SN4 that detects the intake air temperature, which is the temperature of the intake air. The air flow sensor SN2 is attached between the air cleaner 31 and the throttle valve body 32. The intake manifold pressure sensor SN3 and the intake manifold temperature sensor SN4 are attached to a surge tank 36. The intake manifold temperature sensor SN4 corresponds to the "intake air temperature sensor" in the claims.

[0032] The engine 1 is provided with a PCV system 50 for returning blow-by gas, which is an unburned air-fuel mixture that has leaked from the combustion chamber 6 into the crankcase 11, to the intake passage 30. The PCV system 50 includes a PCV passage 51 that connects the crankcase 11 to the intake passage 30, and a PCV valve 52 that is provided at the connection between the crankcase 11 and the PCV passage 51 and opens and closes the PCV passage 51. The PCV passage 51 is connected to the surge tank 36 of the intake passage 30. That is, the intake passage 30 is provided with a blow-by gas introduction section 51A that is connected to the PCV passage 51 and through which blow-by gas is introduced. The PCV valve 52 opens when the pressure in the intake passage 30 becomes lower than the pressure in the crankcase 11, allowing the blow-by gas to flow into the intake passage 30.

[0033] (Control system) The control configuration of the vehicle V will be described with reference to the block diagram of Fig. 4. The vehicle V is comprehensively controlled by a controller (control device) 100. The controller 100 is composed of a CPU, ROM, RAM, and the like.

[0034] The controller 100 receives detection signals from various sensors mounted on the vehicle V. In addition to the sensors SN1 to SN7 described above, the vehicle V is also provided with an accelerator position sensor SN8 that detects the accelerator position, i.e., the amount of depression of the accelerator pedal 80, a vehicle speed sensor SN9 that detects the speed of the vehicle V, and an atmospheric pressure sensor SN10 that measures the atmospheric pressure in the driving environment of the vehicle V. Information detected by these sensors SN1 to SN10 (engine speed, intake air volume, intake manifold pressure, intake manifold temperature, water temperature, oil temperature, oil pressure, accelerator position, vehicle speed, atmospheric pressure), etc., is sequentially input to the controller 100. The controller 100 controls each part of the vehicle V while executing various determinations and calculations based on the above information. That is, the controller 100 is electrically connected to the spark plug 15, the injector 16, the throttle motor 35 (throttle valve 33), the transmission 60, etc., and outputs control signals to these devices based on the results of the above calculations, etc.

[0035] (Condensate inflow suppression control) The intake air flowing through the intake passage 30 contains moisture. In particular, blow-by gas contains a relatively large amount of moisture, and in this embodiment, by introducing blow-by gas into the intake passage 30 as described above, a relatively large amount of water is introduced into the intake passage 30. The water introduced into the intake passage 30 condenses and accumulates in the intake passage 30 when the temperature of the intake passage 30 etc. drops due to the vehicle being stopped, i.e., the engine 1 being stopped, etc. In this embodiment, the condensed water accumulates near X in Fig. 3, that is, near the surge tank 36. If the engine 1 is restarted with a relatively large amount of condensed water accumulated in the intake passage 30, the large amount of condensed water will rush into the engine body all at once. 10 A large amount of condensed water may be introduced into the engine body. 10 If the air is introduced too close to the combustion chamber 6, the temperature inside the combustion chamber 6 may drop excessively, causing the combustion of the air-fuel mixture to become unstable.

[0036] Therefore, in the engine 1 of this embodiment, the condensed water in the intake passage 30 is 10The condensed water accumulated in the intake passage 30 is transported to the engine body together with the intake air. 10 When the intake volume (flow rate of intake air) is large, the intake air is introduced into the engine body. 10 In this case, the amount of condensed water introduced into the intake pipe tends to increase. Furthermore, the higher the engine speed, the larger the intake air amount. For this reason, in this embodiment, as the condensed water suppression control, control is performed to forcibly reduce the engine speed and reduce the intake air amount. This condensed water suppression control will be described next.

[0037] By executing a predetermined program, the controller 100 operates to functionally include a judgment unit 101, a condensed water amount estimation unit 102, a condensed water state estimation unit 103, a transmission control unit 104, and a torque control unit 105.

[0038] The determination unit 101 determines whether or not a condition for performing condensed water inflow suppression control, i.e., a condition for forcibly reducing the engine rotation speed, is satisfied. The condensed water amount estimation unit 102 estimates the amount of condensed water, which is the amount of condensed water accumulated in the intake passage 30 in the form of liquid or solid. The condensed water state estimation unit 103 estimates the state of the condensed water accumulated in the intake passage 30 (whether it is all liquid, a mixture of liquid and solid, or all solid). The transmission control unit 104 controls the operation of the transmission 60. The torque control unit 105 controls (changes) the engine torque, which is the output torque of the engine 1.

[0039] FIG. 5 is a flow chart showing the procedure of the condensed water inflow suppression control performed by the controller 100. -Chart.

[0040] The controller 100 (condensed water amount estimation unit 102) estimates the amount of intake manifold condensed water, which is the amount of liquid or solid water (liquid or solid) accumulated in the intake passage 30 (surge tank 36) (step S1). FIG. 6 is a flowchart showing the procedure for estimating the amount of intake manifold condensed water, which is performed by the controller 100 (condensed water amount estimation unit 102). This amount of intake manifold condensed water corresponds to the "amount of accumulated condensed water" in the claims.

[0041] The controller 100 first calculates the PCV flow rate, which is the flow rate (amount of blow-by gas flowing in per unit time) into the intake passage 30 (step S21). The greater the difference between the pressure in the crankcase 11 and the pressure in the intake passage 30, the greater the PCV flow rate. The pressure in the crankcase 11 is approximately the same as atmospheric pressure. Thus, the controller 100 calculates the PCV flow rate based on the atmospheric pressure detected by the atmospheric pressure sensor SN10 and the intake manifold pressure detected by the intake manifold pressure sensor SN3, i.e., the pressure in the intake passage 30 (surge tank 36), so that the greater the difference between the intake manifold pressure and atmospheric pressure, the greater the PCV flow rate.

[0042] Next, the controller 100 calculates the amount of moisture introduced into the intake passage 30 (the amount introduced per unit time). In this embodiment, the moisture introduced into the intake passage 30 is mainly derived from blow-by gas. Thus, the controller 100 calculates the amount of water introduced into the intake passage 30 as a result of the introduction of blow-by gas into the intake passage 30, that is, the amount of PCV inflow water vapor, which is the amount of water introduced into the intake passage 30 together with the blow-by gas, as the amount of moisture introduced into the intake passage 30 (step S22). The higher the PCV flow rate, the greater the amount of PCV inflow water vapor. Furthermore, the higher the temperature in the oil pan 21, the greater the amount of water that evaporates from the oil pan 21 and is mixed into the blow-by gas, and therefore the greater the amount of PCV inflow water vapor. Based on this, the controller 100 calculates the amount of water vapor flowing into the PCV based on the PCV flow rate calculated in step S21 and the oil temperature detected by the oil temperature sensor SN6, i.e., the temperature of the lubricating oil in the oil pan 21, so that the amount of water vapor flowing into the PCV increases as the PCV flow rate increases and as the oil temperature increases.

[0043] Next, the controller 100 calculates the amount of inflowing condensed water, which is the amount of water in a liquid or solid state out of the amount of PCV inflowing water vapor (step S23). The controller 100 calculates the amount of inflowing condensed water using saturated water vapor characteristics. Specifically, the lower the temperature of the intake air flowing through the intake passage 30, the greater the amount of water present in liquid or solid form within the intake passage 30. Thus, the controller 100 calculates the amount of inflowing condensed water based on the intake manifold temperature detected by the intake manifold temperature sensor SN4 so that the amount of inflowing condensed water increases as the intake manifold temperature decreases.

[0044] Next, the controller 100 extracts the liquid and solid condensed water accumulated in the intake passage 30 from the engine body. 10 The amount of water introduced into the intake passage 30 (amount introduced per unit time) is calculated (step S24). The water present in the intake passage 30 is in the form of liquid or gas and is transported to the engine body. 10 When the condensed water accumulated in the intake passage 30 contains solids and the amount of liquid water is small, and when the amount of vaporized water is small, 10 Therefore, when the condensed water accumulated in the intake passage 30 contains solids, the controller 100 calculates the amount of water removed from the cylinder as 0 (zero). On the other hand, when the condensed water accumulated in the intake passage 30 is only liquid, the controller 100 calculates the amount of water removed from the cylinder as 0 (zero). 10 The amount of water introduced into the cylinder (hereinafter referred to as the amount of liquid water drawn into the cylinder) and the amount of accumulated liquid and solid condensed water that has evaporated and is in the gaseous state and is transported to the engine body 10 The amount of water introduced into the cylinder (hereinafter referred to as the amount of gas and water sucked into the cylinder) is calculated, and the sum of these values ​​is calculated as the amount of water removed by the cylinder.

[0045] As will be described later, the controller 100 determines whether the liquid and solid condensed water accumulated in the intake passage 30 is all in a liquid state, a mixture of liquid and solid, or all in a solid state, and based on the determination made in the previous calculation cycle, determines whether to set the amount of condensed water removed by the cylinder to 0 or to calculate the amount of liquid water sucked into the cylinder and the amount of gaseous water sucked into the cylinder and calculate the total value of these as the amount of condensed water removed by the cylinder.

[0046] When the condensed water accumulated in the intake passage 30 is only liquid, the larger the amount of condensed water accumulated in the intake passage 30 and the larger the intake air flow rate, the more likely it is that the engine body 10 Therefore, the controller 100 calculates the cylinder suction amount based on the amount of intake manifold condensed water calculated one calculation cycle before (i.e., the amount of liquid water accumulated in the intake passage 30) and the intake air amount detected by the air flow sensor SN2 so that the larger the amount of intake manifold condensed water and the larger the intake air amount, the larger the cylinder suction amount.

[0047] When the condensed water accumulated in the intake passage 30 is only liquid, the higher the temperature of the intake air flowing through the intake passage 30 and the larger the amount of condensed water accumulated in the intake passage 30, the more the condensed water will vaporize in the intake passage 30 and be transported to the engine body. 10 The amount of water introduced into the engine increases. 10 Therefore, the controller 100 calculates the amount of gaseous water to be sucked into the cylinder based on the intake manifold temperature detected by the intake manifold temperature sensor SN4, the amount of intake manifold condensed water calculated one calculation cycle before, and the intake air amount detected by the air flow sensor SN2 so that the amount of gaseous water to be sucked into the cylinder increases as the intake manifold temperature increases, the amount of intake manifold condensed water increases, and the intake air amount increases.

[0048] When the controller 100 determines that all of the liquid and solid condensed water accumulated in the intake passage 30 is in a liquid state, it calculates the amount of liquid water sucked into the cylinder and the amount of gaseous water sucked into the cylinder as described above, and calculates the sum of these values ​​as the amount removed by the cylinder.

[0049] Next, the controller 100 calculates the amount of intake manifold condensed water based on the amount of inflow condensed water and the amount of water removed by the cylinder (step S25). Specifically, the controller 100 integrates the amount of inflow condensed water minus the amount of water removed by the cylinder, and calculates this integrated value as the amount of intake manifold condensed water.

[0050] After calculating the amount of intake manifold condensed water, the controller 100 estimates the state of the liquid and solid water accumulated in the intake passage 30, that is, the state of the water corresponding to the amount of intake manifold condensed water calculated in step S1 (step S2). Specifically, as described above, the controller 100 estimates whether the liquid and solid water accumulated in the intake passage 30 is all in a liquid state, a mixture of liquid and solid, or all in a solid state.

[0051] The controller 100 estimates the temperature of the liquid and solid water accumulated in the intake passage 30 and determines the state of the intake manifold condensed water amount based on this temperature. Specifically, when the temperature of the liquid and solid water accumulated in the intake passage 30 is equal to or higher than a predetermined first temperature higher than 0°C, the controller 100 estimates that the water is all in a liquid state, when the temperature is lower than a predetermined second temperature lower than 0°C, the controller 100 estimates that the water is all in a solid state, and in all other cases the controller 100 estimates that the water is in a mixed state of liquid and solid.

[0052] Here, the higher the temperature of the engine body 10, the higher the temperature inside the intake passage 30, and therefore the higher the temperature of the liquid and solid water accumulated in the intake passage 30. Also, the higher the temperature of the intake air flowing through the intake passage 30, the higher the temperature of the liquid and solid water accumulated in the intake passage 30. Also, the lower the vehicle speed, the lower the amount of cooling of the intake passage 30 by the wind while traveling, and therefore the lower the temperature of the intake passage 30. The temperature of the liquid and solid water deposited in the intake passage 30 increases, and the temperature of the liquid and solid water deposited in the intake passage 30 also increases. Therefore, the controller 100 estimates the temperature based on the coolant temperature detected by the water temperature sensor SN5, the intake air temperature detected by the intake manifold temperature sensor SN4, and the vehicle speed detected by the vehicle speed sensor SN9 so that the temperature of the liquid and solid water deposited in the intake passage 30 increases as the coolant temperature, the intake air temperature, and the vehicle speed increase.

[0053] Next, the controller 100 (determination unit 101) determines whether the amount of intake manifold condensed water calculated in step S1 is equal to or greater than a predetermined determination amount (step S3). If the determination is NO, meaning the amount of intake manifold condensed water is less than the determination amount, the controller 100 (transmission control unit 104) does not perform condensed water suppression control, but performs normal control (step S11).

[0054] When normal control is performed, controller 100 (transmission control unit 104) controls transmission 60 in accordance with a preset shift schedule. That is, controller 100 sets the gear position of transmission 60 to a gear position that has been preset and stored in controller 100. Specifically, the gear position of transmission 60 during normal control is changed in accordance with vehicle speed and accelerator opening, and controller 100 stores preset gear positions for vehicle speed and accelerator opening in a map or the like. In step S11, controller 100 extracts from the map or the like a gear position that corresponds to the vehicle speed detected by vehicle speed sensor SN9 and the accelerator opening detected by accelerator opening sensor SN8, and sets the gear position of transmission 60 to this extracted gear position.

[0055] Furthermore, when normal control is being performed, the controller 100 (torque control unit 105) controls the engine torque to become a normal engine torque. Specifically, the controller 100 sequentially calculates a required engine torque, which is the engine torque required of the engine 1, based on the engine speed detected by the crank angle sensor SN1 and the accelerator opening. When normal control is being performed, the controller 100 controls the throttle valve 33 and the injector 16 so that the engine torque becomes this required engine torque. In other words, the controller 100 changes the opening of the throttle valve 33 and changes the amount of fuel injected from the injector 16 so that the required engine torque is realized.

[0056] If the determination in step S3 is NO, the controller 100 sets the restriction start flag to 0 (step S12) and ends the process (return to step S1).

[0057] The restriction start flag is a flag that is set to 1 when condensation water suppression control is performed, and is set to 0 when normal control is performed as described above. Note that the control start flag is set to 0 when the engine 1 is stopped.

[0058] Returning to step S3, if the determination in step S3 is YES and the amount of intake manifold condensed water is equal to or greater than the determination amount, the controller 100 (determination unit 101) determines whether the state of the liquid / solid water accumulated in the intake passage 30 estimated in step S2 is either a state in which all is liquid or a state in which liquid and solid are mixed, that is, whether at least a portion of the liquid / solid water accumulated in the intake passage 30 is liquid or whether the water is all solid (step S4).

[0059] If the determination in step S4 is NO and it is determined that all of the liquid and solid water accumulated in the intake passage 30 is solid, the controller 100 proceeds to step S11 to perform normal control and sets the restriction start flag to 0 in step S12.

[0060] On the other hand, if the determination in step S4 is YES, the liquid and solid matter accumulated in the intake passage 30 If it is determined that at least a portion of the water is liquid, the controller 100 determines whether a specific condition is met, that is, the engine speed is less than a second speed or the restriction start flag is set to 1. The second speed is set in advance and stored in the controller 100. For example, the second speed is set to about 5000 rpm. The second speed corresponds to the "second determination speed" in the claims.

[0061] If the determination in step S5 is NO and the specific condition is not met, the controller 100 proceeds to step S11 to perform normal control and sets the restriction start flag to 0 in step S12. Note that the specific condition is not met when the engine speed is equal to or higher than the second speed and the restriction start flag is 0, that is, when the engine speed increases to equal to or higher than the second speed without condensation water prevention control being implemented after the engine is started.

[0062] On the other hand, if the determination in step S5 is YES and the specific condition is met, the controller 100 determines whether the engine speed is equal to or higher than the second speed (step S6).

[0063] If the determination in step S6 is NO and the engine speed is less than the second speed, the controller 100 further determines whether the engine speed is equal to or greater than the first speed (step S9). The first speed is preset to a value lower than the second speed and stored in the controller 100. For example, the first speed is set to about 4000 rpm. The first speed corresponds to the "determination speed" in the claims.

[0064] If the determination in step S9 is NO and the engine speed is less than the first speed, the controller 100 proceeds to step S11 to perform normal control and sets the restriction start flag to 0 in step S12.

[0065] On the other hand, if the determination in step S9 is YES and the engine rotation speed is equal to or higher than the first rotation speed (and lower than the second rotation speed), the controller 100 (transmission control unit 104) performs an upshift (step S10). That is, the controller 100 forcibly changes the gear position of the transmission 60 to the next higher gear position from the current gear position without following the normal shift schedule. When the upshift is performed, the engine rotation speed decreases. After step S10, the controller 100 sets the restriction start flag to 1 (step S8) and ends the process (return to step S1). Here, the control of performing the upshift in step S10 corresponds to the "forced upshift control" in the claims.

[0066] Returning to step S6, if the determination in step S6 is YES and the engine speed is equal to or higher than the second speed, the controller 100 implements torque limitation to reduce the engine torque (step S7). That is, the controller 100 (torque control unit 105) controls the throttle valve 33 (throttle motor 35) and the injector 16 so that the engine torque is lower than the current engine torque, not the requested engine torque. In this embodiment, the throttle valve 33 and the injector 16 are controlled so that the engine torque is lower than the current engine torque by a predetermined value. Note that if the value obtained by subtracting the predetermined value from the current engine torque is greater than the requested engine torque, the engine torque is controlled to the requested engine torque. When the engine torque decreases, the engine speed decreases. After step S7, the controller 100 sets the restriction start flag to 1 (step S8) and ends the process (returning to step S1).

[0067] In this embodiment, when the specific condition is not met, the amount of intake manifold condensed water, which is the amount of liquid and solid water accumulated in the intake passage 30, is equal to or greater than the determination amount, and at least a portion of the water is liquid, if the engine speed reaches or exceeds the first speed, a forced upshift is performed, thereby reducing the engine speed. When the engine speed increases to or exceeds the second speed, the engine torque is reduced, thereby reducing the engine speed. Also, when a specific condition is met, the amount of intake manifold condensed water, which is the amount of liquid and solid water accumulated in the intake passage 30, is equal to or greater than a determination amount, and at least a portion of the water is liquid, and the engine speed increases to or exceeds the second speed without a forced upshift or reduction in engine torque being performed, the forced upshift or reduction in engine torque is prohibited.

[0068] (action, etc.) As described above, in the engine according to the above embodiment, when the specific condition is not met, if the amount of intake manifold condensed water, which is the amount of liquid and solid water accumulated in the intake passage 30, is equal to or greater than the determination amount, and at least a portion of the water is liquid, and the engine speed reaches or exceeds the first rotational speed, an upshift is forcibly performed, thereby forcibly reducing the engine speed. Therefore, if the amount of intake manifold condensed water is equal to or greater than the determination amount and a large amount of condensed water flows from the intake passage 30 to the engine body, 10 When there is a risk of air flowing into the intake passage 30, 10 This reduces the intake air flow rate to the engine body along with the intake air. 10 Therefore, it is possible to prevent the combustion of the air-fuel mixture in the combustion chamber from becoming unstable due to the inflow of condensed water.

[0069] In particular, when the engine speed is higher than the first rotation speed and the intake flow rate is large, the intake air and the engine body 10 When the amount of condensed water that flows into the engine is likely to increase, a forced upshift is performed. 10 In addition, since the engine speed is less than the first speed, the engine body 10 When the amount of condensed water flowing into the transmission is kept small, normal control is carried out without forcibly shifting up, so that good driving can be ensured by reducing the chances of the gear stage being changed at a timing unexpected by the driver.

[0070] Furthermore, when the specific condition is not satisfied and the engine speed exceeds the second speed, the engine torque is reduced, which forces the engine speed to be reduced. Therefore, while it becomes difficult to reduce the engine speed by shifting up due to the transmission 60 being in the highest gear position, the amount of condensed water in the intake manifold is equal to or greater than the determination amount, and a large amount of condensed water flows from the intake passage 30 to the engine body. 10 Even if there is still a risk of the intake air flowing into the engine body from the intake passage 30, 10 Therefore, the intake air flow rate to the engine body can be further reduced. 10 This can further reduce the amount of condensed water that flows into the combustion chamber, thereby reliably preventing the combustion of the air-fuel mixture in the combustion chamber from becoming unstable due to the inflow of condensed water.

[0071] In the above embodiment, a forced upshift or a reduction in engine torque is performed when at least a portion of the liquid or solid water accumulated in the intake passage 30 is liquid. Therefore, when at least a portion of the liquid or solid water accumulated in the intake passage 30 is liquid, the condensed water is released into the engine body. 10 This condensed water is easily introduced into the engine body 10 In addition, when all of the condensed water is solid, that is, when the condensed water is in the form of ice and adheres to the wall surface of the intake passage 30, the introduction of the condensed water into the engine body can be reliably prevented. 10 When it is considered that the torque will not flow into the target range, forced upshifting and reduction of engine torque are prohibited, so that good driving can be ensured by reducing the chances of upshifting and reduction of engine torque occurring at a timing unexpected by the driver.

[0072] In the above embodiment, when a specific condition is met, the amount of intake manifold condensed water, which is the amount of liquid and solid water accumulated in the intake passage 30, is equal to or greater than the determination amount, and at least a portion of the water is liquid, if the engine speed increases to the second speed or higher without a forced upshift or reduction in engine torque being performed, a forced upshift or reduction in engine torque is prohibited. If the engine speed suddenly rises to or exceeds the second speed before a forced upshift or reduction in engine torque is performed, the forced upshift or reduction in engine torque is prohibited regardless of the amount of intake manifold condensed water and the corresponding water state. Therefore, even if the driver performs a sudden acceleration, the increase in engine speed is suppressed, preventing the driver from feeling uncomfortable.

[0073] As described above, the higher the temperature of the engine body 10, the higher the temperature inside the intake passage 30, and therefore the higher the temperature of the liquid and solid water accumulated in the intake passage 30. Furthermore, the higher the temperature of the intake air flowing through the intake passage 30, the higher the temperature of the liquid and solid water accumulated in the intake passage 30. Accordingly, in the above embodiment, the temperature of the liquid and solid water accumulated in the intake passage 30 is estimated based on the coolant temperature detected by the water temperature sensor SN5 and the intake air temperature detected by the intake manifold temperature sensor SN4, so that the higher the coolant temperature and the intake air temperature, the higher the temperature of the liquid and solid water accumulated in the intake passage 30. Therefore, the temperature and state of the liquid and solid water accumulated in the intake passage 30 can be estimated with high accuracy.

[0074] Furthermore, as described above, the lower the vehicle speed, the lower the amount of cooling of the intake passage 30 due to wind while the vehicle is traveling, and therefore the higher the temperature of the intake passage 30 and the higher the temperature of the liquid and solid water accumulated in the intake passage 30. In response to this, in the above embodiment, the temperature of the liquid and solid water accumulated in the intake passage 30 is estimated based on the vehicle speed detected by the vehicle speed sensor SN9 so that the temperature increases as the vehicle speed increases. Therefore, the temperature and state of the liquid and solid water accumulated in the intake passage 30 can be estimated more reliably and accurately.

[0075] (Variation) In the above embodiment, a forced upshift and a reduction in engine torque are performed when at least a portion of the liquid / solid water accumulated in the intake passage is liquid. However, regardless of the state of the water, a forced upshift or a reduction in engine torque may be performed if the amount of condensed water in the intake manifold is equal to or greater than a predetermined amount.

[0076] In addition, in the above embodiment, the control for forcibly reducing the engine torque may be omitted. Also, the control for prohibiting the forcible upshift and reduction of the engine torque when the specific condition is met may be omitted. In other words, the forcible upshift and reduction of the engine torque may be implemented even when the specific condition is met.

[0077] Furthermore, the procedure for estimating the amount of intake manifold condensed water, which is the amount of liquid and solid water accumulated in the intake passage, and the temperature and state of the water, is not limited to the above.

[0078] Furthermore, the specific configuration of the engine is not limited to the above. For example, the number of cylinders of the engine is not limited to the above. Furthermore, the above-described control may be applied to an engine having an EGR device that recirculates a portion of the exhaust gas flowing through the exhaust passage to the intake passage as EGR gas. In an engine having an EGR device, moisture contained in the EGR gas is likely to condense and accumulate in the intake passage. Therefore, if the above-described control is applied to such an engine, it is possible to effectively prevent the introduction of condensed water into the engine body, resulting in unstable combustion of the air-fuel mixture. [Explanation of symbols]

[0079] 1 engine 10 Engine body 30 Intake passage 60 Transmission 101 Judgment section 102 Condensed water amount estimation unit 103 Condensed water state estimation unit 104 Transmission control unit 105 Torque control section SN4 Intake manifold temperature sensor (intake air temperature sensor) SN5 Water Temperature Sensor

Claims

1. A control device for controlling a vehicle equipped with an engine having an engine body and an intake passage through which intake air introduced into the engine body flows, and a transmission that transmits output rotation of the engine to wheels while changing the speed, a transmission control unit capable of changing the gear position of the transmission in accordance with a preset gear shift schedule; a condensed water amount estimation unit that estimates an amount of condensed water accumulated in the intake passage; a determination unit that determines whether the amount of accumulated condensed water estimated by the condensed water amount estimation unit is equal to or greater than a predetermined determination amount, The vehicle control device is characterized in that, when the judgment unit determines that the amount of accumulated condensed water is equal to or greater than the judgment amount and the engine speed is equal to or greater than a predetermined judgment speed, the transmission control unit performs forced upshift control to increase the gear position of the transmission regardless of the shift schedule, and when the judgment unit determines that the amount of accumulated condensed water is equal to or greater than the judgment amount and the engine speed is less than the judgment speed, the transmission control unit changes the gear position of the transmission in accordance with the shift schedule.

2. 2. The vehicle control device according to claim 1, a torque control unit for controlling engine torque; The torque control unit reduces engine torque when the amount of accumulated condensed water is equal to or greater than the judgment amount and the engine speed is equal to or greater than a predetermined second judgment speed that is higher than the judgment speed.

3. 3. The vehicle control device according to claim 2, The torque control unit reduces engine torque when the engine speed becomes equal to or higher than the second judgment speed after the forced upshift control is implemented, and prohibits a reduction in engine torque when the engine speed becomes equal to or higher than the second judgment speed when the forced upshift control is not implemented.

4. The vehicle control device according to any one of claims 1 to 3, a condensed water state estimation unit that estimates a state of condensed water accumulated in the intake passage, The vehicle control device is characterized in that the transmission control unit performs the forced upshift control when the amount of accumulated condensed water is equal to or greater than the judgment amount, the engine speed is equal to or greater than a predetermined judgment speed, and the condensed water state estimation unit estimates that at least a portion of the condensed water is liquid.

5. 5. The vehicle control device according to claim 4, a water temperature sensor for detecting a coolant temperature, which is the temperature of the coolant that cools the engine body; an intake air temperature sensor for detecting an intake air temperature, which is the temperature of the intake air flowing through the intake passage; The condensed water state estimation unit determines the state of the condensed water based on the detected values ​​of the water temperature sensor and the intake air temperature sensor.

6. A control device for controlling a vehicle equipped with an engine having an engine body and an intake passage through which intake air introduced into the engine body flows, and a transmission that transmits the output rotation of the engine to the wheels while changing the speed, a transmission control unit capable of changing the gear position of the transmission in accordance with a preset gear shift schedule; a condensed water amount estimation unit that estimates an amount of condensed water accumulated in the intake passage; a condensed water state estimation unit that estimates a state of condensed water accumulated in the intake passage; a water temperature sensor for detecting a coolant temperature, which is the temperature of the coolant that cools the engine body; an intake air temperature sensor that detects an intake air temperature, which is the temperature of the intake air flowing through the intake passage; a determination unit that determines whether the amount of accumulated condensed water estimated by the condensed water amount estimation unit is equal to or greater than a predetermined determination amount, the transmission control unit, when the determination unit determines that the amount of accumulated condensed water is equal to or greater than the determination amount and the condensed water state estimating unit estimates that at least a portion of the condensed water is liquid, performs forced upshift control to increase a gear position of the transmission regardless of the shift schedule, The condensed water state estimation unit determines the state of the condensed water based on the detected values ​​of the water temperature sensor and the intake air temperature sensor.

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