JP2012149555A - On-board control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-board control device for an internal combustion engine that prevents an occupant from building a feeling of discomfort, caused by a blowing rate of fuel injected from a port injection valve and an in-cylinder injection valve during an idle operation being changed.SOLUTION: When the port injection valve 14 is set as an injection valve for injecting fuel during the idle operation, an electronic control unit 100 allows the injection valve for injecting fuel to be changed from the port injection valve 14 to the in-cylinder injection valve 12 if a deposit accumulation amount DP is larger than a predetermined amount DPth. Meanwhile, the unit prohibits the injection valve for injecting fuel after this change from being changed to the port injection valve 14.

Description

  The present invention is applied to an internal combustion engine that includes a port injection valve that injects fuel into an intake port and an in-cylinder injection valve that directly injects fuel into a cylinder, and a ratio of fuel to be injected from each injection valve The present invention relates to an in-vehicle internal combustion engine control device including a control unit for controlling the engine.

  Conventionally, as this type of on-vehicle internal combustion engine control device, for example, the one described in Patent Document 1 is known. In the technique described in Patent Document 1, the ratio of fuel to be injected from each injection valve is controlled as follows. That is, during idling when the internal combustion engine is in a cold state, fuel is injected only from the port injection valve. This is because the in-cylinder temperature is low and the amount of intake air is small, so that the injected fuel is difficult to atomize and good combustion of the fuel injected from the in-cylinder injection valve is difficult to obtain. On the other hand, during idling when the internal combustion engine is in a warm state, fuel is not injected from the port injection valve, but fuel is injected only from the in-cylinder injection valve.

  In addition, during idle operation, fuel injection from only the port injection valve is continued and fuel injection from the in-cylinder injection valve is not performed, and the engine temperature rises with engine operation or the engine temperature is high In this case, deposits accumulate in the injection hole of the in-cylinder injection valve. Therefore, in the technique described in Patent Document 1, the deposit amount accumulated in the cylinder injection valve is estimated, and when the deposit accumulation amount becomes larger than a predetermined amount, the fuel injection from the port injection valve is stopped. The deposits accumulated in the in-cylinder injection valve are removed by injecting fuel from the in-cylinder injection valve.

  In the technique described in Patent Document 1, when the duration of fuel injection from the in-cylinder injection valve becomes equal to or longer than a predetermined time, the fuel injection from the in-cylinder injection valve is stopped and the port injection is performed because the deposit is removed. The fuel is injected from the valve. This is because the magnitude of the sound and vibration generated by driving the in-cylinder injection valve is larger than the sound and vibration generated by driving the port injection valve.

JP 2006-274923 A

  By the way, in such a conventional in-vehicle internal combustion engine control device, an injection valve that injects fuel due to various factors, including those for the purpose of removing the deposit during the idling operation, is a port injection valve and an in-cylinder injection valve. Will be changed between. For this reason, it has been found by the inventor that the occupant feels uncomfortable when the fuel injection valve is frequently changed, for example, when the vehicle is stopped.

  Such a problem is particularly noticeable when the fuel injection valve is changed between the port injection valve and the in-cylinder injection valve during idle operation. Even if the fuel spray ratio is changed in a range larger than “0” and smaller than “1”, it can be generated in almost any degree.

  The present invention has been made in view of such circumstances, and the purpose of the present invention is to the occupant due to the change in the ratio of fuel injected from the port injection valve and the in-cylinder injection valve during idle operation. An object of the present invention is to provide an in-vehicle internal combustion engine control device that can suppress discomfort.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
(1) The invention according to claim 1 is applied to an internal combustion engine including a port injection valve that injects fuel into an intake port and a cylinder injection valve that directly injects fuel into a cylinder. An in-vehicle internal combustion engine control device including a control unit that controls a blowing rate of fuel to be injected, the gist of which is that the control unit prohibits the change of the blowing rate during idle operation.

  According to this configuration, the change in the ratio of fuel injected from each injector during idle operation is prohibited. Therefore, it is possible to suppress discomfort to the occupant due to the change in the ratio of the fuel injected from the port injection valve and the in-cylinder injection valve during idle operation.

  (2) The invention according to claim 2 is the in-vehicle internal combustion engine control device according to claim 1, wherein the control unit sets the injection valve that performs fuel injection during idle operation based on the engine operation state. And in-cylinder injection valve, and prohibiting the change of the injection valve that performs fuel injection during the idling operation from the currently set injection valve to another injection valve is prohibited. It is a summary. In this case, it is possible to prevent the passenger from feeling uncomfortable due to the change of the injection valve that performs fuel injection during idle operation.

  (3) The invention described in claim 3 is the in-vehicle internal combustion engine control device according to claim 2, further comprising an estimation unit that estimates a deposit accumulation amount of the in-cylinder injection valve. When the port injection valve is set as an injection valve for performing fuel injection, when the deposit accumulation amount exceeds a predetermined amount, the injection valve for performing fuel injection is changed from the port injection valve to the in-cylinder injection valve. The gist of the invention is to prohibit the change of the injection valve that performs fuel injection after the change to the port injection valve.

  During idling operation, fuel injection from only the port injection valve is continued, and fuel injection from the in-cylinder injection valve is not performed, and the engine temperature rises with engine operation or the engine temperature is high. As a result, deposits accumulate in the injection hole of the in-cylinder injection valve. Therefore, the deposit amount accumulated in the cylinder injection valve is estimated, and when the deposit accumulation amount becomes larger than a predetermined amount, the fuel injection from the port injection valve is stopped, and the fuel injection from the cylinder injection valve is stopped. It is desirable to remove the deposit accumulated on the in-cylinder injection valve.

However, if the change of the fuel injection valve for the purpose of removing the deposit is prohibited, the deposit of the in-cylinder injection valve cannot be removed.
According to the above configuration, when fuel is being injected from the port injection valve during idle operation, if the deposit accumulation amount exceeds a predetermined amount, the fuel injection from the port injection valve is stopped and in-cylinder injection is performed. The fuel is injected from the valve. Further, after such change of the injection valve, change of the injection valve that performs fuel injection during the idle operation is prohibited. Therefore, it is possible to prevent the passenger from feeling uncomfortable due to the change of the injection valve while avoiding the inconvenience that the deposit of the in-cylinder injection valve cannot be removed.

  (4) According to a fourth aspect of the present invention, in the in-vehicle internal combustion engine control device according to the second or third aspect, the air-fuel ratio learning of the in-cylinder injection system is performed when a predetermined learning execution condition is satisfied during idle operation. An injection unit that performs fuel injection when the predetermined learning execution condition is satisfied when the port injection valve is set as an injection valve that performs fuel injection during idle operation. The gist of the invention is to allow the valve to be changed from the port injection valve to the in-cylinder injection valve, but prohibit the change of the injection valve that performs fuel injection after the change to the port injection valve. .

  In an internal combustion engine, air-fuel ratio feedback control is performed to set the air-fuel ratio of the air-fuel mixture to its target value. However, there are individual differences among the various parts constituting the fuel supply system, and variations also occur due to changes in these parts over time. For this reason, due to such variations, a steady deviation occurs between the feedback correction value and its reference value, and there is a possibility that the air-fuel ratio feedback control cannot be performed accurately as it is. Therefore, as described above, if the air-fuel ratio learning control of the in-cylinder injection system is performed when a predetermined learning execution condition is satisfied during idle operation, such a steady deviation is updated as a learning value. Thus, the air-fuel ratio feedback control by the in-cylinder injection system can be performed accurately.

  However, if the change of the fuel injection valve for the purpose of executing the air-fuel ratio learning of the in-cylinder injection system is prohibited, the opportunity for executing the air-fuel ratio learning of the in-cylinder injection system is reduced, and the air-fuel ratio by the in-cylinder injection system is reduced. There is a risk that the feedback control cannot be performed accurately.

  According to the above configuration, when the port injection valve is set as an injection valve for performing fuel injection during idle operation, fuel injection from the port injection valve is stopped when a predetermined learning execution condition is satisfied, and the in-cylinder Fuel injection from the injection valve is performed. Further, after such change of the injection valve, change of the injection valve that performs fuel injection during the idle operation is prohibited. Therefore, it is possible to prevent the passenger from feeling uncomfortable due to the change of the injection valve while securing the execution opportunity of the air-fuel ratio learning of the in-cylinder injection system.

  (5) The invention according to claim 5 is applied to an internal combustion engine including a port injection valve that injects fuel into the intake port and a cylinder injection valve that directly injects fuel into the cylinder. An on-vehicle internal combustion engine control device including a control unit that controls a ratio of fuel to be injected, wherein the control unit is configured such that the in-cylinder injection valve is set as an injection valve that performs fuel injection during idle operation. The gist of the invention is to prohibit the fuel injection valve from being changed from the cylinder injection valve to the port injection valve.

  According to this configuration, when the in-cylinder injection valve is set as an injection valve that performs fuel injection during idle operation, the injection valve that performs fuel injection is prohibited from being changed from the in-cylinder injection valve to the port injection valve. The Accordingly, it is possible to suppress discomfort to the passenger due to the change of the injection valve.

1 is a schematic diagram showing a schematic configuration of an on-vehicle internal combustion engine electronic control device according to an embodiment of the present invention and a fuel supply system that is a control target thereof. (A), (b) is a schematic diagram which shows the operation | movement aspect which concerns on the pressure | voltage rise operation of the high pressure pump of the embodiment. The flowchart which shows the process sequence of the in-cylinder injection ratio setting process at the time of the idling operation which concerns on the same embodiment.

Hereinafter, an embodiment in which the vehicle internal combustion engine control device according to the present invention is embodied as an electronic control device that comprehensively controls the vehicle internal combustion engine will be described with reference to FIGS. 1 to 3.
FIG. 1 schematically shows the configuration of an electronic control device 100 according to the present embodiment and a fuel supply system of an internal combustion engine 10 that is a control target thereof.

  As shown in the upper part of FIG. 1, the internal combustion engine 10 is a V-type six-cylinder engine having six cylinders 11, a port injection valve 14 that injects fuel into the intake port 13, and fuel into each cylinder 11. And an in-cylinder injection valve 12 for direct injection.

The fuel stored in the fuel tank 21 is supplied to each of the injection valves 12 and 14.
As shown in the lower part of FIG. 1, a feed pump 20 is provided in the fuel tank 21. The feed pump 20 is an electric fuel pump and discharges fuel at a predetermined pressure during engine operation. A supply passage 41 is connected to the feed pump 20.

  The supply passage 41 is branched in the middle, and one is connected to the low pressure delivery pipe 16 to which the port injection valve 14 is connected. The other of the branched supply passages 41 is connected to the high-pressure pump 30, and a part of the fuel discharged from the feed pump 20 is introduced into the high-pressure pump 30 through the supply passage 41. The supply passage 41 is provided with a filter 22, and fine foreign matters contained in the fuel are removed through the filter 22.

  The supply passage 41 is connected to a return passage 23 for returning a part of the fuel discharged from the feed pump 20 into the fuel tank 21. A pressure regulator 24 is provided in the return passage 23. When the pressure of the fuel in the supply passage 41 exceeds a predetermined pressure, the pressure regulator 24 is opened, and a part of the fuel in the supply passage 41 is returned to the fuel tank 21. It is. As a result, the pressure of the fuel in the supply passage 41 is suppressed from becoming excessively high, and the fuel is supplied to the low pressure delivery pipe 16 at a predetermined pressure as the feed pump 20 is driven.

  The fuel introduced into the high pressure pump 30 through the supply passage 41 is pressurized by the high pressure pump 30. A high-pressure passage 42 is connected to the discharge side of the high-pressure pump 30. The high pressure passage 42 is connected to the high pressure delivery pipe 15 to which the in-cylinder injection valve 12 is connected. Thereby, the fuel pressurized by the high pressure pump 30 is stored in the high pressure delivery pipe 15 and directly injected into each cylinder 11 through the in-cylinder injection valve 12. In the vicinity of the high-pressure pump 30 in the high-pressure passage 42, the flow of fuel from the high-pressure pump 30 side to the high-pressure delivery pipe 15 side is allowed, while the flow of fuel from the high-pressure delivery pipe 15 side to the high-pressure pump 30 side is prohibited. A check valve 43 is provided. By this check valve 43, the back flow of fuel from the high pressure delivery pipe 15 side to the high pressure pump 30 side is suppressed.

  A relief passage 44 connected to the fuel tank 21 is connected to the high-pressure delivery pipe 15. The relief passage 44 is provided with a relief valve 45 that opens when the fuel pressure in the high-pressure delivery pipe 15 exceeds a predetermined pressure. Thereby, when the pressure of the fuel in the high pressure delivery pipe 15 becomes a predetermined pressure or higher, the relief valve 45 is opened, and a part of the fuel in the high pressure delivery pipe 15 is returned to the fuel tank 21 through the relief passage 44.

  The fuel supply system of the internal combustion engine 10 according to the present embodiment configured as described above is controlled by the electronic control unit 100 that controls the internal combustion engine 10 in an integrated manner. Connected to the electronic control unit 100 are a water temperature sensor 60 for detecting the engine cooling water temperature THW, a rotational speed sensor 61 for detecting the engine rotational speed NE, and an air flow meter 62 for detecting the intake air amount GA of the internal combustion engine 10. . Further, a vehicle speed sensor 63 for detecting the vehicle speed SPD, an accelerator position sensor 64 for detecting the accelerator operation amount ACCP by the driver, an air-fuel ratio sensor 65 for detecting the exhaust air-fuel ratio AF, and the like are connected to the electronic control unit 100. .

  The electronic control unit 100 takes in signals output from these various sensors 60 to 65, executes various arithmetic processes, and controls each part of the engine based on the results. Specifically, the throttle valve provided in the intake passage is controlled based on the engine rotational speed NE and the accelerator operation amount ACCP to regulate the intake air amount GA, and based on the intake air amount GA and the air-fuel ratio AF. The fuel injection amount is set, and the fuel injection amount is adjusted by controlling the in-cylinder injection valve 12 and the port injection valve 14.

  Further, a blowing ratio of the fuel injection amount injected from each injection valve 12, 14 is set based on the engine speed NE and the engine load factor KL, and each injection valve 12, 14 is set based on this blowing ratio. By injecting fuel, the fuel injection mode is changed according to the engine operating state. At this time, depending on the engine operating state, fuel may be injected only from the in-cylinder injection valve 12 or the port injection valve 14.

  Further, the electronic control unit 100 adjusts the amount of fuel pumped from the high pressure pump 30 to the high pressure delivery pipe 15 according to the amount of fuel injected from the in-cylinder injection valve 12. Hereinafter, the configuration of the high-pressure pump 30 will be described in detail with reference to FIG. 2, and the metering mode of the pumping amount will be described. FIGS. 2A and 2B are schematic views showing an operation mode of the high-pressure pump 30 related to the pressure increasing operation.

  As shown in the center of FIG. 2A, the high-pressure pump 30 has a cylinder 31, and a pressurizing chamber 33 is defined by the cylinder 31 and a plunger 32 inserted therein. A lifter 34 is fixed to the end of the plunger 32 opposite to the pressurizing chamber 33. The lifter 34 is in contact with a drive cam 51 fixed to the intake camshaft 50 of the internal combustion engine 10 by the urging force of the spring 35. Thus, the plunger 32 periodically reciprocates within the cylinder 31 by the action of the drive cam 51 that rotates together with the intake camshaft 50.

  A spill valve 36 that closes and opens between the supply passage 41 and the pressurization chamber 33 is provided at a portion where the pressurization chamber 33 and the supply passage 41 are connected. The spill valve 36 is urged in the valve opening direction by a spring 38. The spill valve 36 is driven against the urging force of the spring 38 by the electromagnetic force of the solenoid 39 excited based on a control command from the electronic control device 100 and is closed.

  In the high-pressure pump 30 configured as described above, as shown in FIG. 2A, the spill valve 36 is opened when the plunger 32 descends as the drive cam 51 rotates. Thereby, the fuel discharged from the feed pump 20 is introduced into the pressurizing chamber 33. As shown in FIG. 2B, the spill valve 36 is closed when the plunger 32 rises as the drive cam 51 rotates, and the fuel in the pressurizing chamber 33 is added as the plunger 32 rises. Pressed. Thereby, when the pressure of the fuel in the pressurizing chamber 33 becomes larger than the pressure of the fuel in the high-pressure delivery pipe 15, the check valve 43 is opened so that the pressurized fuel is supplied to the high-pressure delivery pipe 15. become.

  The electronic control unit 100 basically changes the closing timing of the spill valve 36 based on the fuel injection amount from the in-cylinder injection valve 12, thereby making the fuel pressure in the high-pressure delivery pipe 15 suitable for fuel injection. The amount of fuel pumped by the high-pressure pump 30 is adjusted so as to maintain the pressure. Specifically, the closing timing of the spill valve 36 is set so that the period during which the spill valve 36 is closed while the plunger 32 is raised becomes longer as the fuel injection amount from the in-cylinder injection valve 12 increases. To do. As a result, when the fuel injection amount is large, more fuel is pumped to the high pressure delivery pipe 15 and the fuel pressure in the high pressure delivery pipe 15 is maintained. When the spill valve 36 is held open, if the pressure of the fuel in the pressurizing chamber 33 increases due to the vertical movement of the plunger 32, the fuel flows backward to the supply passage 41 side, and excess fuel is supplied from the pressure regulator 24. Is returned to the fuel tank 21. As a result, the pressure increasing operation by the high pressure pump 30 is stopped, the check valve 43 is held in the closed state, and the supply of fuel from the high pressure pump 30 to the high pressure delivery pipe 15 is stopped.

  Further, in the present embodiment, the in-cylinder injection valve 12 and the port injection valve 14 are controlled based on the air-fuel ratio of the air-fuel mixture (hereinafter referred to as the actual air-fuel ratio) obtained from the air-fuel ratio AF of the exhaust gas detected by the air-fuel ratio sensor 65. A so-called air-fuel ratio feedback control is performed in which the fuel injection amount is feedback-controlled. In this air-fuel ratio feedback control, the actual air-fuel ratio and the target air-fuel ratio are set so that the actual air-fuel ratio matches the target value of the air-fuel ratio of the air-fuel mixture formed in the combustion chamber of the internal combustion engine 10 (hereinafter referred to as target air-fuel ratio). The feedback correction value K is calculated based on the deviation tendency.

  In addition, there are individual differences among the various parts constituting the fuel supply system, and variations occur due to changes over time. For this reason, due to such variations, a steady deviation occurs between the feedback correction value K and its reference value (specifically, “1.0”), and the air-fuel ratio feedback control cannot be performed accurately as it is. There is a fear.

  Therefore, in the present embodiment, air-fuel ratio learning control is performed in which such a steady deviation is learned as the air-fuel ratio learning value G when a predetermined learning execution condition is satisfied. Specifically, a plurality of learning regions are defined by the operating state of the internal combustion engine 10 (engine speed NE and engine load factor KL), and an air-fuel ratio learning value G is set for each learning region. The air-fuel ratio learning value is updated separately for each region. As one of these learning areas, an idle operation area of the internal combustion engine 10 is set.

When executing the air-fuel ratio feedback, the learning region is specified from the engine operating state, and the air-fuel ratio learning value G corresponding to the learning region is read. The target fuel injection amount TQ is corrected by the feedback correction value K and the air-fuel ratio learning value G according to the following relational expression.

TQ = TQ × K + GK

Next, the fuel injection amount setting mode will be specifically described.

  First, based on the intake air amount GA, a fuel amount (hereinafter, target fuel injection amount TQ) at which the air-fuel ratio of the air-fuel mixture becomes a target air-fuel ratio (basically a theoretical air-fuel ratio) is calculated. Further, based on the engine speed NE and the engine load factor KL, the ratio of fuel injected from the in-cylinder injection valve 12 (hereinafter, in-cylinder injection ratio Rd (0 ≦ Rd ≦ 1, Rd + Rp = 1, where Rp is The ratio of the fuel injected from the port injection valve 14) is calculated, and the in-cylinder injection valve 12 is set so as to satisfy the following relational expression based on the target fuel injection amount TQ and the in-cylinder injection ratio Rd. A control target value for the amount of fuel injected from (hereinafter referred to as the required fuel injection amount TQd) and a control target value for the amount of fuel injected from the port injection valve 14 (hereinafter referred to as the required fuel injection amount TQp) are set.

TQd = TQ × Rd

TQp = TQ × (1-Rd)

Thereafter, the drive of the injection valve 12 is controlled so that the same amount of fuel as the required fuel injection amount TQd is injected from the in-cylinder injection valve 12, and the same amount as the required fuel injection amount TQp from the port injection valve 14. The drive of the injection valve 14 is controlled so that fuel is injected.

In the present embodiment, when the internal combustion engine 10 is in the high load high rotation region, the in-cylinder injection ratio Rd is set to “1”.
Further, when the internal combustion engine 10 is in the medium load mid-rotation region, the in-cylinder injection ratio Rd is appropriately within a range smaller than “0” and smaller than “1” based on the engine speed NE and the engine load factor KL. It is set (0 <Rd <1, 0 <Rp <1). Specifically, the in-cylinder injection ratio Rd is set to be larger as the engine speed NE is larger and as the engine load factor KL is larger.

  Further, when the internal combustion engine 10 is in the low load and low rotation region, the in-cylinder injection ratio Rd is set to either “1” or “0”. For example, when the internal combustion engine 10 is idling after a cold start, the injected fuel is difficult to atomize because the temperature in the cylinder 11 is low and the intake air amount GA is also small, and the fuel is injected from the in-cylinder injection valve 12. However, it is difficult to obtain good combustion of the injected fuel. Therefore, in such a case, the fuel injection is performed only from the port injection valve 14 by setting the in-cylinder injection ratio Rd to “0”.

  By the way, when the engine temperature rises during engine operation in a state where fuel injection from only the port injection valve 14 is continued during idle operation and fuel injection from the cylinder injection valve 12 is not performed, the cylinder injection valve Deposits accumulate in the 12 nozzle holes. Therefore, the amount of deposit accumulated in the in-cylinder injection valve 12 (hereinafter, deposit accumulation amount DP) is estimated. When the deposit accumulation amount DP becomes larger than the predetermined amount DPth, the in-cylinder injection ratio Rd is changed to “1”, the fuel injection from the port injection valve 14 is stopped, and the in-cylinder injection valve 12 By performing fuel injection, deposits accumulated in the in-cylinder injection valve 12 are removed. Note that the time (hereinafter referred to as port injection continuation time) in which fuel injection is performed only by the port injection valve 14 after the engine coolant temperature THW becomes equal to or higher than a predetermined temperature at which deposits start to accumulate in the injection hole of the in-cylinder injection valve 12. Measure and estimate the deposit amount DP based on the duration.

  Further, when the fuel injection is continued from only the port injection valve 14 during the idling operation, the above-described air-fuel ratio learning value G of the port injection system is updated. Here, it is desirable to update the air-fuel ratio learning value G of the in-cylinder injection system during idle operation. Therefore, it is conceivable to update the air-fuel ratio learning value G of the in-cylinder injection system when a predetermined learning execution condition is satisfied during idle operation.

  By the way, in the in-cylinder injection system, since it is necessary to inject fuel into the cylinder 11 that is at a high pressure, it is necessary to increase the fuel pressure several times or more compared to the port injection system. Therefore, the driving sound of the in-cylinder injection valve 12 is louder than that of the port injection valve 14. Further, as described above, when fuel injection is performed from the in-cylinder injection valve 12, the high-pressure pump 30 is driven by the intake camshaft 50. Therefore, when fuel injection is performed only from the port injection valve 14, that is, high pressure. Compared with the case where the pump 30 is not driven, the driving noise and vibration of the entire fuel supply system are increased. Therefore, if the injection valves 12 and 14 that inject fuel during idle operation are frequently changed due to various factors, the driving sound and vibration of the entire fuel supply system frequently change greatly, which causes the passenger to May cause discomfort.

  Therefore, in the present embodiment, it is prohibited to change the injection valve 12 (14) that performs fuel injection during idle operation from the injection valve 12 (14) set at that time to another injection valve 14 (12). I am doing so.

  However, if the change for the purpose of updating the air-fuel ratio learning value G of the in-cylinder injection system is prohibited, the opportunity for updating the air-fuel ratio learning value of the in-cylinder injection system is reduced, and the air-fuel ratio feedback control by the in-cylinder injection system is reduced. May not be able to be performed properly.

Further, if the change for the purpose of removing the deposit described above is prohibited, the deposit accumulated on the in-cylinder injection valve 12 cannot be removed.
Therefore, in order to avoid such inconvenience, in the present embodiment, when the port injection valve 14 is set as an injection valve for performing fuel injection during idle operation, and when a predetermined learning execution condition is satisfied, the in-cylinder injection system In order to update the learned value of the air-fuel ratio, it is allowed to change the injection valve for performing fuel injection from the port injection valve 14 to the in-cylinder injection valve 12. However, after the change, it is prohibited to change the injection valve that performs fuel injection to the port injection valve 14.

  Further, in this embodiment, when the port injection valve 14 is set as an injection valve for performing fuel injection during idle operation, the injection valve for performing fuel injection when the deposit accumulation amount DP is greater than a predetermined amount DPth. Is permitted to be changed from the port injection valve 14 to the in-cylinder injection valve 12. However, the change of the injection valve that performs fuel injection to the port injection valve 14 after the change is prohibited.

  Next, the in-cylinder injection ratio setting process during idle operation according to the present embodiment will be described in detail with reference to FIG. FIG. 3 is a flowchart showing the processing procedure of the setting process. Further, this series of processes is repeatedly executed at predetermined intervals during idle operation.

  As shown in FIG. 3, in this series of processing, first, in step S1, it is determined whether or not the flag F is “0”. Since the flag F is initially set to “0”, an affirmative determination is made in step S1, and then the process proceeds to step S2.

  In step S2, the engine coolant temperature THW at that time is read, and then the process proceeds to step S. In step S3, it is determined whether the engine coolant temperature THW is equal to or lower than a predetermined temperature T1 (for example, 80 ° C.). That is, it is determined whether or not the internal combustion engine 10 is in a cold state. Here, when the engine coolant temperature THW is equal to or lower than the predetermined temperature T1, the process proceeds to step S4.

  In step S4, the in-cylinder injection ratio Rd is set to “0” so that the internal combustion engine 10 is in a cold state and fuel is injected only from the port injection valve 14, and this series of processes is temporarily terminated.

On the other hand, when the engine coolant temperature THW is higher than the predetermined temperature T1 (step S3: “NO”), the process proceeds to step S5.
In step S5, it is determined whether or not the deposit accumulation amount DP is larger than a predetermined amount DPth. Here, if the deposit accumulation amount DP is larger than the predetermined amount DPth, the process proceeds to step S6, and the flag F is set to “1”. Then, the process proceeds to step S7.

  In step S7, the deposit accumulated in the injection hole of the in-cylinder injection valve 12 is an amount that cannot be ignored, and the in-cylinder injection ratio Rd is set to “1” so that the fuel injection is performed from the in-cylinder injection valve 12. This series of processes is once terminated.

  On the other hand, if the engine coolant temperature THW is higher than the predetermined temperature T1, but the deposit accumulation amount DP is equal to or less than the predetermined amount DPth (step S5: “NO”), the process proceeds to step S8.

  In step S8, it is determined whether an execution condition for air-fuel ratio learning of the in-cylinder injection system is satisfied. If the execution condition is satisfied, the process proceeds to steps S6 and S7, and this series of processes is temporarily terminated. That is, the in-cylinder injection ratio Rd is set to “1” so that fuel is injected from the in-cylinder injection valve 12 in order to update the air-fuel ratio learning value of the in-cylinder injection system.

  On the other hand, if the execution condition is not satisfied in step S8 (step S8: “NO”), the process proceeds to step S4, and this series of processes is temporarily terminated. That is, fuel injection from the port injection valve 14 is continued, and the injection valve that performs fuel injection is not unnecessarily changed.

  By repeatedly executing such processing, the flag F is set to “1” in step S6, and if a negative determination is made in step S1 of the next control cycle (step S1: “NO”), then step S7 is performed. Proceed to That is, fuel injection from the in-cylinder injection valve 12 is continued, and the injection valve that performs fuel injection is not unnecessarily changed.

Note that when the operation region of the internal combustion engine 10 has shifted from the idle operation region to another operation region, the flag F is reset to “0”.
The electronic control device 100 functions as a control unit, an estimation unit, and a learning unit according to the present invention.

According to the on-vehicle internal combustion engine control device according to the present embodiment described above, the following effects can be obtained.
(1) The injection valve that performs fuel injection during the idling operation through the electronic control unit 100 is set to one of the port injection valve 14 and the in-cylinder injection valve 12 based on the engine operating state, and the fuel injection is performed during the idling operation. Changing the injection valve 12 (14) to be performed from the injection valve 12 (14) set at that time to another injection valve 14 (12) is prohibited. Therefore, it is possible to suppress discomfort to the occupant due to the change of the injection valve 12 (14) that performs fuel injection during idle operation.

  (2) The deposit amount DP of the in-cylinder injection valve 12 is estimated. In addition, when the port injection valve 14 is set as an injection valve that performs fuel injection during idle operation, if the deposit accumulation amount DP is greater than a predetermined amount DPth, the injection valve that performs fuel injection is the port injection valve 14. It is allowed to be changed to the in-cylinder injection valve 12. On the other hand, the change of the injection valve that performs fuel injection after the change to the port injection valve 14 is prohibited. According to such an aspect, when fuel is injected from the port injection valve 14 during idle operation, the fuel injection from the port injection valve 14 is stopped if the deposit accumulation amount DP is greater than the predetermined amount DPth. Then, fuel injection from the in-cylinder injection valve 12 is performed. Further, after such change of the injection valve, change of the injection valve that performs fuel injection during the idle operation is prohibited. Therefore, it is possible to prevent the passenger from feeling uncomfortable due to the change of the injection valve while avoiding the inconvenience that the deposit of the in-cylinder injection valve 12 cannot be removed.

  (3) The air-fuel ratio learning of the in-cylinder injection system is performed when a predetermined learning execution condition is satisfied during idle operation. Further, when the port injection valve 14 is set as an injection valve for performing fuel injection during idle operation, if the predetermined learning execution condition is satisfied, the injection valve for performing fuel injection is injected from the port injection valve 14 into the in-cylinder injection. While the change to the valve 12 is permitted, the change of the injection valve that performs fuel injection after the change to the port injection valve 14 is prohibited. According to such an aspect, when the port injection valve 14 is set as an injection valve that performs fuel injection during idle operation, fuel injection from the port injection valve 14 is stopped when a predetermined learning execution condition is satisfied, Fuel injection from the in-cylinder injection valve 12 is performed. Further, after such change of the injection valve, change of the injection valve that performs fuel injection during the idle operation is prohibited. Therefore, it is possible to prevent the passenger from feeling uncomfortable due to the change of the injection valve while securing the execution opportunity of the air-fuel ratio learning of the in-cylinder injection system.

  In addition, the vehicle-mounted internal combustion engine control apparatus according to the present invention is not limited to the configuration exemplified in the above-described embodiment, and may be implemented as, for example, the following forms appropriately modified.

  In the above embodiment, when the port injection valve 14 is set as an injection valve that performs fuel injection during idle operation, the injection valve that performs fuel injection from the port injection valve 14 to the cylinder when a predetermined learning execution condition is satisfied The internal injection valve 12 is allowed to be changed. However, the present invention is not limited to this, and the change of the injection valve can be prohibited even when the execution condition of the air-fuel ratio learning of the in-cylinder injection system is satisfied. In this case, the change frequency of the injection valve can be further reduced, and discomfort to the passenger due to the change of the injection valve can be further suppressed.

  In the above embodiment, fuel is injected from either the port injection valve 14 or the in-cylinder injection valve 12 during idle operation. Then, it is prohibited to change the injection valve that performs fuel injection during idle operation from the in-cylinder injection valve 12 to the port injection valve 14. However, instead of such an injection mode, fuel injection may be performed from both the port injection valve 14 and the in-cylinder injection valve 12. In this case, for example, the in-cylinder injection ratio Rd is appropriately set in a range larger than “0” and smaller than “1” based on the engine operating state (0 <Rd <1). What is necessary is just to prohibit the change of the internal injection ratio Rd. Even in this case, it is possible to suppress discomfort to the occupant due to the change in the ratio of fuel injected from the port injection valve 14 and the in-cylinder injection valve 12 during idle operation. it can.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 11 ... Cylinder, 12 ... In-cylinder injection valve, 13 ... Intake port, 14 ... Port injection valve, 15 ... High pressure delivery pipe, 16 ... Low pressure delivery pipe, 20 ... Feed pump, 21 ... Fuel tank, 22 DESCRIPTION OF SYMBOLS ... Filter, 23 ... Return passage, 24 ... Pressure regulator, 30 ... High pressure pump, 31 ... Cylinder, 32 ... Plunger, 33 ... Pressure chamber, 34 ... Lifter, 35 ... Spring, 36 ... Spill valve, 38 ... Spring, 39 ... Solenoid, 41 ... Supply passage, 42 ... High pressure passage, 43 ... Check valve, 44 ... Relief passage, 45 ... Relief valve, 50 ... Intake camshaft, 51 ... Drive cam, 60 ... Water temperature sensor, 61 ... Rotational speed sensor 62 ... Air flow meter, 63 ... Vehicle speed sensor, 64 ... Accelerator position sensor, 65 ... Air-fuel ratio sensor, 100 ... Electronic control device .

Claims (5)

Control applied to an internal combustion engine having a port injection valve for injecting fuel into an intake port and an in-cylinder injection valve for directly injecting fuel into a cylinder, and controlling a blow-off rate of fuel injected from each injection valve In-vehicle internal combustion engine control device comprising a unit,
The on-board internal combustion engine control device, wherein the control unit prohibits the change of the blowing ratio during idle operation. The on-vehicle internal combustion engine control device according to claim 1,
The control unit sets an injection valve that injects fuel during idle operation to either the port injection valve or the in-cylinder injection valve based on an engine operating state, and performs injection of fuel during the idle operation Is prohibited from changing from the injection valve set at that time to another injection valve. The in-vehicle internal combustion engine control device according to claim 2,
An estimation unit for estimating a deposit amount of the in-cylinder injection valve;
When the port injection valve is set as an injection valve for injecting fuel during idle operation, the control unit is configured such that when the deposit accumulation amount is greater than a predetermined amount, the injection valve for injecting fuel is the port. An on-vehicle internal combustion engine control device characterized by permitting a change from an injection valve to the in-cylinder injection valve while prohibiting an injection valve that performs fuel injection after the change from being changed to the port injection valve . In the in-vehicle internal combustion engine control device according to claim 2 or 3,
A learning unit that performs air-fuel ratio learning of the in-cylinder injection system when a predetermined learning execution condition is satisfied during idle operation;
When the port injection valve is set as an injection valve that injects fuel during idle operation, the control unit determines whether the injection valve that performs fuel injection from the port injection valve when the predetermined learning execution condition is satisfied. An on-vehicle internal combustion engine control device characterized by allowing change to the in-cylinder injection valve while prohibiting change of the injection valve that performs fuel injection after the change to the port injection valve. Control applied to an internal combustion engine having a port injection valve for injecting fuel into an intake port and an in-cylinder injection valve for directly injecting fuel into a cylinder, and controlling a blow-off rate of fuel injected from each injection valve In-vehicle internal combustion engine control device comprising a unit,
When the in-cylinder injection valve is set as an injection valve for performing fuel injection during idle operation, the control unit changes the injection valve for performing fuel injection from the in-cylinder injection valve to the port injection valve. An on-vehicle internal combustion engine control device characterized by being prohibited.

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