JP6708039B2 - Automobile - Google Patents

Description

The present invention relates to a vehicle, and more particularly, to a vehicle including an engine and a fuel supply device.

Conventionally, as this type of vehicle, there has been proposed one including an engine having a port injection valve and an in-cylinder injection valve, and a fuel supply device for supplying fuel to the port injection valve and the in-cylinder injection valve (for example, , Patent Document 1). Here, the fuel supply device includes a fuel tank, a feed pump that supplies fuel from the fuel tank to a first passage to which a port injection valve is connected, a check valve provided in the first passage, and a feed valve in the first passage. And a high-pressure fuel pump that pressurizes fuel on the port injection valve side of the check valve and supplies the pressurized fuel to the second passage to which the in-cylinder injection valve is connected. In this vehicle, the feed pump is controlled so that the fuel pressure of the fuel supplied to the port injection valve becomes the target fuel pressure.

JP, 2005-218595, A

In the above-mentioned automobile, when the target fuel pressure of the port injection valve is reduced when the fuel supply to the engine is started, the fuel pressure from the feed pump is reduced according to the target fuel pressure. However, the fuel pressure on the feed pump side may fall below the fuel pressure on the port injection valve side, and the check valve may close. When the check valve is closed, the pulsation of the fuel pressure in the first passage generated by the driving of the high-pressure fuel pump increases, and the fuel supply device or the like vibrates, which may cause abnormal noise.

An object of the vehicle of the present invention is to suppress generation of abnormal noise due to vibration of a fuel supply device that supplies fuel to a port injection valve and an in-cylinder injection valve.

The vehicle of the present invention employs the following means in order to achieve the above-mentioned main object.

The automobile of the present invention is
An engine having a port injection valve for injecting fuel into the intake pipe, and an in-cylinder injection valve for injecting fuel into the cylinder,
A fuel tank, a first pump for supplying the fuel of the fuel tank to a first passage to which the port injection valve is connected, and a fuel pressure provided on the first passage and on the side of the first pump is the port injection valve side. And a check valve that opens when the fuel pressure on the first pump side is less than or equal to the fuel pressure on the port injection valve side when the fuel pressure is higher than the fuel pressure of A fuel supply device having a second pump that pressurizes the fuel on the port injection valve side and supplies it to a second passage to which the in-cylinder injection valve is connected;
A control device for controlling the engine and the fuel supply device;
A car comprising:
The control device controls the first pump so that the fuel pressure of the fuel supplied to the port injection valve becomes a target fuel pressure,
Further, when the starting actual fuel pressure, which is the actual fuel pressure of the fuel supplied to the port injection valve at the start of fuel supply to the engine, is higher than the target fuel pressure, the control device supplies the fuel to the port injection valve. The first pump is controlled such that the fuel pressure of the fuel gradually changes from the actual fuel pressure at the start toward the target fuel pressure,
That is the summary.

In the vehicle of the present invention, the first pump is controlled so that the fuel pressure of the fuel supplied to the port injection valve becomes the target fuel pressure. Further, when the starting actual fuel pressure, which is the actual fuel pressure of the fuel supplied to the port injection valve at the start of fuel supply to the engine, is higher than the target fuel pressure, the fuel pressure of the fuel supplied to the port injection valve is changed from the starting actual fuel pressure to the target fuel pressure. The first pump is controlled so that it gradually changes toward the fuel pressure. By such control, the fuel pressure on the first pump side in the first passage of the check valve is suppressed from becoming equal to or lower than the fuel pressure on the port injection valve side of the check valve, and the closing of the check valve is suppressed. Accordingly, the pulsation of the fuel pressure in the first passage is prevented from increasing due to the driving of the second pump, so that the vibration of the fuel supply device can be suppressed and the generation of abnormal noise can be suppressed.

In the vehicle of the present invention, the control device sets the target fuel pressure to be lower when a predetermined time has elapsed after starting the supply of fuel to the engine than when the predetermined time has elapsed. May be set.

It is a block diagram which shows the outline of a structure of the hybrid vehicle 20 as an Example of this invention. It is a block diagram which shows the outline of a structure of the engine 22 and the fuel supply apparatus 60. 5 is a flowchart showing an example of a target fuel pressure setting routine executed by the engine ECU 24 of the embodiment.

Next, modes for carrying out the present invention will be described using examples.

FIG. 1 is a schematic diagram showing a schematic configuration of a hybrid vehicle 20 as an embodiment of the present invention, and FIG. 2 is a schematic diagram showing a schematic configuration of an engine 22 and a fuel supply device 60.

As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine 22, a fuel supply device 60, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, and a hybrid electronic control unit. (Hereinafter referred to as “HVECU”) 70.

The engine 22 is configured as an internal combustion engine that outputs power using fuel such as gasoline or light oil. As shown in FIG. 2, the engine 22 has a port injection valve 125 that injects fuel into the intake port and an in-cylinder injection valve 126 that injects fuel into the cylinder. Since the engine 22 has the port injection valve 125 and the in-cylinder injection valve 126, it can be operated in any of the port injection mode, the in-cylinder injection mode, and the common injection mode.

In the port injection mode, the air cleaned by the air cleaner 122 is sucked through the throttle valve 124, and the fuel is injected from the port injection valve 125 to mix the air and the fuel. Then, this air-fuel mixture is sucked into the combustion chamber through the intake valve 128, explosively burned by electric sparks from the spark plug 130, and the reciprocating motion of the piston 132 pushed down by the energy is converted into the rotary motion of the crankshaft 26. .. In the in-cylinder injection mode, similarly to the port injection mode, air is sucked into the combustion chamber, fuel is injected from the in-cylinder injection valve 126 during the intake stroke or after reaching the compression stroke, and explosive combustion is caused by electric sparks from the spark plug 130. Then, the rotational movement of the crankshaft 26 is obtained. In the common injection mode, when injecting air into the combustion chamber, fuel is injected from the port injection valve 125, fuel is injected from the in-cylinder injection valve 126 in the intake stroke and compression stroke, and explosive combustion is caused by electric sparks from the spark plug 130. Then, the rotational movement of the crankshaft 26 is obtained. These injection modes are switched based on the operating state of the engine 22.

Exhaust gas from the combustion chamber is discharged to the outside air through a purifying device 134 having a purifying catalyst (three-way catalyst) that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). To be done.

As shown in FIG. 2, the fuel supply device 60 is configured as a device that supplies fuel to the port injection valve 125 and the in-cylinder injection valve 126 of the engine 22. The fuel supply device 60 includes a fuel tank 61, a feed pump (first pump) 62 that supplies the fuel in the fuel tank 61 to a low pressure side passage (first passage) 63 to which the port injection valve 125 is connected, and a low pressure side passage. A check valve 64 provided in 63 and a high pressure side passage (second passage) to which the in-cylinder injection valve 126 is connected by pressurizing fuel in the low pressure side passage 63 closer to the port injection valve 125 than the check valve 64. And a high-pressure fuel pump (second pump) 65 that supplies the fuel to the fuel cell 66.

The feed pump 62 and the check valve 64 are arranged in the fuel tank 61. The feed pump 62 is configured as an electric pump that operates by receiving supply of electric power from the battery 50. The check valve 64 opens when the fuel pressure (fuel pressure) on the feed pump 62 side in the low pressure side passage 63 is higher than the pressure on the port injection valve 125 side, and the pressure on the feed pump 62 side changes to the port injection valve 125 side. When the pressure is less than, the valve is closed.

The high-pressure fuel pump 65 is a pump that is driven by the power (rotation of the cam shaft) from the engine 22 to pressurize the fuel in the low-pressure passage 63. The high-pressure fuel pump 65 is connected to its suction port to open and close when pressurizing the fuel, and is connected to its discharge port to prevent backflow of the fuel and hold the fuel pressure in the high-pressure passage 66. And a check valve 65b. The high-pressure fuel pump 65 draws fuel from the feed pump 62 when the electromagnetic valve 65a is opened while the engine 22 is operating, and when the electromagnetic valve 65a is closed, it is driven by the power from the engine 22. Fuel supplied to the high-pressure passage 66 is pressurized by intermittently sending the fuel compressed by an operating plunger (not shown) to the high-pressure passage 66 via the check valve 65b. When the high pressure fuel pump 65 is driven, the fuel pressure in the low pressure side passage 63 and the fuel pressure in the high pressure side passage 66 pulsate according to the rotation of the engine 22 (rotation of the camshaft).

The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24. Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM for storing a processing program, a RAM for temporarily storing data, an input/output port, and a communication port. ..

Signals from various sensors necessary for controlling the operation of the engine 22 and the fuel supply device 60 are input to the engine ECU 24 via input ports. The signals input to the engine ECU 24 include, for example, the crank position θcr from the crank position sensor 140 that detects the rotational position of the crankshaft 26, and the cooling water temperature Tw from the water temperature sensor 142 that detects the temperature of the cooling water of the engine 22. Can be mentioned. Further, the cam position θca from the cam position sensor 144 that detects the rotational position of the intake camshaft that opens and closes the intake valve 128 and the exhaust camshaft that opens and closes the exhaust valve can be mentioned. Further, the throttle opening TH from the throttle valve position sensor 146 that detects the position of the throttle valve 124, the intake air amount Qa from the air flow meter 148 attached to the intake pipe, and the temperature sensor 149 attached to the intake pipe. The intake air temperature Ta can also be mentioned. In addition, the air-fuel ratio AF from the air-fuel ratio sensor 135a attached to the exhaust pipe and the oxygen signal O2 from the oxygen sensor 135b attached to the exhaust pipe can also be mentioned. Further, the fuel pressure Pfp from the fuel pressure sensor 68 that detects the fuel pressure on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 of the fuel supply device 60 (fuel pressure of the fuel supplied to the port injection valve 125), The fuel pressure Pfd from the fuel pressure sensor 69 that detects the fuel pressure in the high pressure side passage 66 (fuel pressure of the fuel supplied to the in-cylinder injection valve 126) can also be mentioned.

Various control signals for controlling the operation of the engine 22 and controlling the fuel supply device 60 are output from the engine ECU 24 via the output port. The signals output from the engine ECU 24 include, for example, a drive signal for the port injection valve 125, a drive signal for the in-cylinder injection valve 126, a drive signal for a throttle motor 136 that adjusts the position of the throttle valve 124, and an igniter. A control signal to the ignition coil 138 that has been converted into a signal can be given. Further, a drive control signal to the feed pump 62 and a drive control signal to the electromagnetic valve 65a of the high-pressure fuel pump 65 can also be given.

The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23.

As shown in FIG. 1, the planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of the planetary gear 30 is connected to the rotor of the motor MG1. The ring gear of the planetary gear 30 is connected to a drive shaft 36 that is connected to the drive wheels 39a and 39b via a differential gear 38. The crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30 via a damper 28.

The motor MG1 is configured as, for example, a synchronous generator motor, and the rotor is connected to the sun gear of the planetary gear 30 as described above. The motor MG2 is configured as, for example, a synchronous generator motor, and the rotor is connected to the drive shaft 36. Inverters 41 and 42 are connected to motors MG1 and MG2, and are also connected to battery 50 via power line 54. The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by an electronic control unit for motor (hereinafter referred to as “motor ECU”) 40.

Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input/output port, and a communication port. .. The motor ECU 40 has signals from various sensors necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 from rotational position detection sensors 43 and 44 that detect rotational positions of rotors of the motors MG1 and MG2. , Θm2, the temperature tm2 of the motor MG2 from a temperature sensor (not shown) that detects the temperature of the motor MG2, and the phase current from a current sensor (not shown) that detects the phase currents of the motors MG1 and MG2 are input through the input port. ing. From the motor ECU 40, switching control signals to a plurality of switching elements (not shown) of the inverters 41 and 42 are output via the output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. Motor ECU 40 calculates rotation speeds Nm1 and Nm2 of motors MG1 and MG2 based on rotation positions θm1 and θm2 of rotors of motors MG1 and MG2 from rotation position detection sensors 43 and 44. Motor ECU 40 calculates motor torque Tm1 that is an estimated value of the drive torque of motor MG1 based on the phase current of motor MG1.

The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery, and is connected to the inverters 41 and 42 via a power line 54. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52.

Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM for storing a processing program, a RAM for temporarily storing data, an input/output port, and a communication port. .. Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via an input port. The signals input to the battery ECU 52 include, for example, the battery voltage Vb from the voltage sensor 51a installed between the terminals of the battery 50, the battery current Ib from the current sensor 51b installed at the output terminal of the battery 50, and the battery 50. The battery temperature Tb from the temperature sensor 51c attached to the can be mentioned. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the charge ratio SOC based on the integrated value of the battery current Ib from the current sensor 51b. The charge ratio SOC is the ratio of the capacity of the electric power that can be discharged from the battery 50 to the total capacity of the battery 50.

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input/output port, and a communication port. Signals from various sensors are input to the HVECU 70 via input ports. Examples of the signal input to the HVECU 70 include an ignition signal from the ignition switch 80 and a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81. Further, an accelerator pedal position Acc from an accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and a vehicle speed sensor 88 from the vehicle speed sensor 88. The vehicle speed V can also be mentioned. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port.

The hybrid vehicle 20 of the embodiment thus configured travels in a hybrid travel (HV travel) mode or an electric travel (EV travel) mode. Here, the HV drive mode is a mode in which the engine 22 is driven while the engine 22 is being driven, and the EV drive mode is a mode in which the engine 22 is not driven.

In the HV traveling mode, the HVECU 70 first sets the required torque Td* required for the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V, and sets the required torque Td* to the rotational speed Np of the drive shaft 36. The required power Pd* required for the drive shaft 36 is calculated by multiplying by. Here, as the rotation speed Np of the drive shaft 36, for example, the rotation speed Nm2 of the motor MG2 or the rotation speed obtained by multiplying the vehicle speed V by a conversion coefficient can be used. Subsequently, the required power Pe* required for the vehicle is calculated by subtracting the charging/discharging required power Pb* (a positive value when discharging from the battery 50) based on the storage ratio SOC of the battery 50 from the required power Pd*. The target power Pe* is output from the engine 22 and the target torque Ne* and the target torque Te* of the engine 22 and the torque command Tm1 of the motors MG1 and MG2 are output so that the required torque Td* is output to the drive shaft 36. *, Tm2* are set. Then, the target rotation speed Ne* and the target torque Te* of the engine 22 are transmitted to the engine ECU 24, and the torque commands Tm1* and Tm2* of the motors MG1 and MG2 are transmitted to the motor ECU 40. When the engine ECU 24 receives the target rotation speed Ne* and the target torque Te* of the engine 22, the intake air amount control of the engine 22 is performed so that the engine 22 is operated based on the target rotation speed Ne* and the target torque Te*. , Fuel injection control, ignition control, etc. The engine ECU 24 also controls the fuel supply device 60 when operating the engine 22. Specifically, the feed pump 62 is set so that the fuel pressure (fuel pressure of the fuel supplied to the port injection valve 125) Pfp on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 becomes the target fuel pressure Pfp*. At the same time, the electromagnetic valve 65a of the high-pressure fuel pump 65 is controlled so that the fuel pressure Pfd in the high-pressure passage 66 becomes the target fuel pressure Pfd*. When the motor ECU 40 receives the torque commands Tm1*, Tm2* of the motors MG1, MG2, the switching control of the plurality of switching elements of the inverters 41, 42 is performed so that the motors MG1, MG2 are driven by the torque commands Tm1*, Tm2*. Do. In the HV traveling mode, when the stop condition of the engine 22 is satisfied, such as when the required power Pe* reaches the stop threshold Pstop or less, the operation of the engine 22 is stopped and the EV traveling mode is entered.

In the EV traveling mode, the HVECU 70 sets the required torque Td* of the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V, sets the torque command Tm1* of the motor MG1 to the value 0, and sets the required torque Td*. The torque command Tm2* of the motor MG2 is set, and the torque commands Tm1* and Tm2* of the motors MG1 and MG2 are transmitted to the motor ECU 40. When the motor ECU 40 receives the torque commands Tm1*, Tm2* of the motors MG1, MG2, the switching control of the plurality of switching elements of the inverters 41, 42 is performed so that the motors MG1, MG2 are driven by the torque commands Tm1*, Tm2*. Do. In this EV traveling mode, when the required condition Pe* calculated in the same manner as in the HV traveling mode reaches the starting threshold value Pstart which is larger than the stopping threshold value Pstop or more, the engine 22 is started when the starting condition is satisfied. 22 is started to shift to the HV traveling mode.

Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly, the target fuel pressure on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 (the target fuel pressure of the fuel supplied to the port injection valve 125 ) A process for setting Pfp* will be described. FIG. 3 is a flowchart showing an example of a target fuel pressure setting routine executed by the engine ECU 24 of the embodiment. This routine is repeatedly executed while the engine 22 is operating.

When the target fuel pressure setting routine is executed, the engine ECU 24 executes processing for inputting the engine speed Ne of the engine 22 (engine speed) Ne and the engine torque Te (step S100). The rotation speed Ne of the engine 22 is input as a value calculated based on the crank angle θcr from the crank position sensor 23. In the planetary gear 30, the engine torque Te is such that the torque from the engine 22 is distributed from the carrier to the sun gear and the ring gear, and the motor MG1 bears a reaction force against the torque distributed to the sun gear. Therefore, the gear ratio ρ of the planetary gear 30 and the motor torque Te The value calculated by the HVECU 70 using the following equation (1) based on Tm1 is input by communication. Note that “ρ” is the number of teeth of the sun gear divided by the number of teeth of the ring gear. Here, the motor torque Tm1 is calculated by the motor ECU 40 based on the phase current of the motor MG1 from the current sensor and input to the HVECU 70 by communication.

Te=-Tm1×(1+ρ)/ρ (1)

Subsequently, using the input engine speed Ne and engine torque Te, a temporary target fuel pressure Pfptag, which is a temporary target value of the fuel pressure on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63, is set. It is set (step S110). The temporary target fuel pressure Pfptag is set to the fuel pressure Pfp1 until a predetermined time Tref (for example, 5 seconds, 6 seconds, 7 seconds) elapses after the fuel supply is started, and the predetermined time Tref is set after the fuel supply is started. After that, the fuel pressure Pfp2 is set lower than the fuel pressure Pfp1. The fuel pressures Pfp1 and Pfp2 are set based on the relationship between the engine speed Ne, the engine torque Te, and the fuel pressures Pfp1 and Pfp2 that are determined in advance by experiments or analysis. When the temporary target fuel pressure Pfptag is set to the fuel pressure Pfp1, the atomization of the fuel can be promoted compared to when the temporary target fuel pressure Pfptag is set to the fuel pressure Pfp2. When the temporary target fuel pressure Pfptag is set to the fuel pressure Pfp2, the power consumption of the feed pump 62 can be suppressed more than when it is set to the fuel pressure Pfp1.

Then, it is determined whether or not it is immediately after the start of fuel supply to the engine 22 (step S120). Immediately after the fuel supply to the engine 22 is started, immediately after the EV drive mode is switched to the HV drive mode and the fuel supply is started when the operation of the engine 22 is started, or the accelerator pedal 83 is turned off. The time immediately after starting the fuel supply to the engine 22 by depressing the accelerator pedal 83 while the fuel supply is stopped (fuel cut) can be mentioned.

If it is not immediately after the fuel supply to the engine 22 is started, the temporary target fuel pressure Pfptag is set to the target fuel pressure Pfp* (step S150), and this routine is ended. When the target fuel pressure Pfp* is set in this way, the engine ECU 24 sets the target fuel pressure Pfp* to the fuel pressure on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 (fuel pressure of fuel supplied to the port injection valve 125). The feed pump 62 is controlled so that

Immediately after the fuel supply to the engine 22 is started, the fuel pressure Pfp is input (step S130). Here, as the fuel pressure Pfp, the one detected by the fuel pressure sensor 68 is input. Note that the fuel pressure Pfp is generally adjusted near the target fuel pressure Pfp* by the control of the feed pump 62 when the fuel supply to the engine 22 continues to some extent. It rises as the temperature of the low-pressure side passage 63 rises due to the heat received by and then decreases as the temperature of the low-pressure side passage 63 decreases. Therefore, while the fuel supply of the engine 22 is stopped, the fuel pressure Pfp may be higher or lower than the temporary target fuel pressure Pfptag (fuel pressure Pfp1 or fuel pressure Pfp2) to some extent.

Then, the input fuel pressure Pfp is compared with the temporary target fuel pressure Pfptag (step S140). Then, when the fuel pressure Pfp is less than or equal to the temporary target fuel pressure Pfptag, the temporary target fuel pressure Pfptag is set to the target fuel pressure Pfp* (step S150), and this routine is ended. When the target fuel pressure Pfp* is set in this way, the engine ECU 24 sets the target fuel pressure Pfp* to the fuel pressure Pfp on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 (fuel pressure of fuel supplied to the port injection valve 125). The feed pump 62 is controlled so that Now, it is considered that the fuel pressure Pfp is less than or equal to the temporary target fuel pressure Pfptag. The feed pump 62 so that the fuel pressure (fuel pressure of the fuel supplied to the port injection valve 125) Pfp on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 becomes the target fuel pressure Pfp* (temporary target fuel pressure Pfptag). Therefore, the fuel pressure on the feed pump 62 side of the check valve 64 in the low pressure side passage 63 is suppressed from becoming equal to or lower than the fuel pressure on the port injection valve 125 side (fuel pressure of fuel supplied to the port injection valve 125) Pfp. The closing of the check valve 64 is suppressed.

When the fuel pressure Pfp exceeds the temporary target fuel pressure Pfptag, the fuel pressure Pfp minus the rate value R is set as the target fuel pressure Pfp* (step S160), and the process returns to the step S130. Then, the fuel pressure Pfp is input, and the processes of steps S130, S140, and S160 are repeated until the input fuel pressure Pfp becomes equal to or less than the temporary target fuel pressure Pfptag. When the fuel pressure Pfp becomes equal to or less than the temporary target fuel pressure Pfptag, the temporary target fuel pressure Pfptag Is set to the target fuel pressure Pfp* (step S150), and this routine ends. Therefore, the target fuel pressure Pfp* is set to decrease at the rate value R from the fuel pressure Pfp at the start of fuel supply to the engine 22 toward the temporary target fuel pressure Pfptag. Here, the rate value R is fed so that the fuel pressure on the port injection valve 125 side (fuel pressure of the fuel supplied to the port injection valve 125) Pfp in the low pressure side passage 63 becomes the target fuel pressure Pfp*. When the pump 62 is controlled, a value determined in advance by experiments, analysis, etc. as a value that is small enough that the fuel pressure on the feed pump 62 side of the check valve 64 on the low pressure side passage 63 does not fall below the fuel pressure on the port injection valve 125 side. Is set as. When the target fuel pressure Pfp* is set in this manner, the fuel pressure Pfp on the port injection valve 125 side of the check valve 64 in the low pressure side passage 63 (fuel pressure of fuel supplied to the port injection valve 125) becomes the target fuel pressure Pfp*. The feed pump 62 is controlled as follows. As a result, it is possible to prevent the fuel pressure in the low pressure side passage 63 on the feed pump 62 side from the check valve 64 from becoming equal to or lower than the fuel pressure on the port injection valve 125 side.

In the embodiment, the target fuel pressure Pfp* is set so as to decrease at the rate value R from the fuel pressure Pfp at the start of the fuel supply to the engine 22 toward the temporary target fuel pressure Pfptag, and the following effects are achieved. Here, as a comparative example, consider a case where the temporary target fuel pressure Pfptag is set to the target fuel pressure Pfp* regardless of the fuel pressure Pfp at the start of fuel supply to the engine 22. In the comparative example, the tentative target fuel pressure Pfptag is set to the target fuel pressure Pfp* regardless of the fuel pressure Pfp at the time of starting the fuel supply to the engine 22, so that the predetermined time Tref elapses after the fuel supply to the engine 22 is started. , The target fuel pressure Pfp* decreases from the fuel pressure Pfp1 to the fuel pressure Pfp2. At this time, the amount of fuel from the feed pump 62 decreases, and the pressure on the feed pump 62 side of the check valve 64 in the low pressure side passage 63 becomes equal to or lower than the pressure on the port injection valve 125 side, and the check valve 64 closes. May speak. When the check valve 64 is closed, the pulsation of the fuel pressure in the low pressure side passage 63 generated by the driving of the high pressure fuel pump 65 becomes large, and the fuel supply device 60 (the low pressure side passage 63, the fuel tank 61, etc.), the vehicle body, etc. It may vibrate and generate abnormal noise.

In the embodiment, when the fuel pressure Pfp at the time of starting the fuel supply to the engine 22 exceeds the temporary target fuel pressure Pfptag, the fuel pressure Pfp at the start of the fuel supply is reduced at the rate value R toward the temporary target fuel pressure Pfptag. The target fuel pressure Pf* is set. This suppresses the pressure on the feed pump 62 side of the low pressure side passage 63 from the check valve 64 to be equal to or lower than the pressure on the port injection valve 125 side, and thus suppresses the check valve 64 from closing. You can Therefore, it is possible to suppress an increase in the pulsation of the fuel pressure in the low pressure side passage 63 generated by the driving of the high pressure fuel pump 65, and to vibrate the fuel supply device 60 (the low pressure side passage 63, the fuel tank 61, etc.), the vehicle body, and the like. It is possible to suppress the occurrence of noise and to suppress the generation of abnormal noise.

According to the hybrid vehicle 20 of the embodiment described above, when the fuel pressure Pfp at the start of fuel supply to the engine 22 is higher than the temporary target fuel pressure Pfptag, the fuel pressure of the fuel supplied to the port injection valve 125 is changed from the fuel pressure Pfp to the temporary target. Since the feed pump 62 is controlled so as to gradually change toward the fuel pressure Pfptag, it is possible to suppress an increase in the pulsation of the fuel pressure in the low pressure side passage 63 that is generated by the driving of the high pressure fuel pump 65, and thus the fuel supply device. It is possible to suppress vibration of the 60 (the low-pressure side passage 63, the fuel tank 61, etc.) and suppress the generation of abnormal noise.

In the hybrid vehicle 20 of the embodiment, when the fuel pressure Pfp at the time of starting the fuel supply to the engine 22 is higher than the temporary target fuel pressure Pfptag, the fuel pressure of the fuel supplied to the port injection valve 125 moves from the fuel pressure Pfp toward the temporary target fuel pressure Pfptag. The feed pump 62 is controlled so as to change with the rate value R. However, the feed pump 62 may be controlled so that the fuel pressure of the fuel supplied to the port injection valve 125 gradually changes from the fuel pressure Pfp toward the temporary target fuel pressure Pfptag. The feed pump 62 may be controlled so that the fuel pressure changes stepwise from the fuel pressure Pfp toward the temporary target fuel pressure Pfptag.

In the hybrid vehicle 20 of the embodiment, the temporary target fuel pressure Pfptag is set to the fuel pressure Pfp1 until the predetermined time Tref elapses after the fuel supply is started, and after the predetermined time Tref elapses after the fuel supply is started. Is set to a fuel pressure Pfp2 lower than the fuel pressure Pfp1, but it may be set to a relatively low fuel pressure Pfp2 without setting the fuel pressure Pfp1 after the fuel supply is started, or the fuel supply may be started. Therefore, the fuel pressure Pfp1 may be set without setting the fuel pressure Pfp2.

The hybrid vehicle 20 of the embodiment includes the engine ECU 24, the motor ECU 40, and the HVECU 70. However, the engine ECU 24, the motor ECU 40, and the HVECU 70 may be configured as a single electronic control unit.

In the embodiment, the hybrid vehicle 20 includes the engine 22, the planetary gear 30, the motors MG1 and MG2, and the battery 50. However, a so-called one-motor hybrid vehicle including an engine, one motor, and a battery may be used. Further, it may be configured as an automobile that does not include a motor and travels using only power from the engine.

Correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the engine 22 corresponds to an “engine”, the fuel supply device 60 corresponds to a “fuel supply device”, and the engine ECU 24 corresponds to a “control device”.

The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the section of means for solving the problem. This is an example for specifically explaining the mode for carrying out the invention, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problem should be made based on the description in that column, and the embodiment is the invention of the invention described in the column of means for solving the problem. This is just a specific example.

Although the embodiments for carrying out the present invention have been described above with reference to the embodiments, the present invention is not limited to these embodiments, and various embodiments are possible within the scope not departing from the gist of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICABILITY The present invention can be used in the automobile manufacturing industry and the like.

20 hybrid vehicle, 22 engine, 23 crank position sensor, 24 engine electronic control unit (engine ECU), 26 crank shaft, 28 damper, 30 planetary gear, 36 drive shaft, 38 differential gear, 39a, 39b drive wheel, 40 motor Electronic control unit (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 50 Battery, 51a Voltage sensor, 51b Current sensor, 51c Temperature sensor, 52 Battery electronic control unit (battery ECU), 54 Power line , 60 fuel supply device, 61 fuel tank, 62 feed pump, 63 low pressure side passage, 64 check valve, 65 high pressure fuel pump, 65a electromagnetic valve, 65b check valve, 66 high pressure side passage, 68, 69 fuel pressure sensor, 70 hybrid Electronic control unit (HVECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 122 air cleaner, 124 throttle Valve, 125 port injection valve, 126 cylinder injection valve, 128 intake valve, 130 spark plug, 132 piston, 134 purification device, 135a air-fuel ratio sensor, 135b oxygen sensor, 136 throttle motor, 138 ignition coil, 140 crank position sensor, 142 water temperature sensor, 143 pressure sensor, 144 cam position sensor, 146 throttle valve position sensor, 148 air flow meter, 149 temperature sensor, MG1, MG2 motor.

Claims (1)

An engine having a port injection valve for injecting fuel into the intake pipe and an in-cylinder injection valve for injecting fuel into the cylinder,
A fuel tank, a first pump for supplying the fuel of the fuel tank to a first passage to which the port injection valve is connected, and a fuel pressure provided on the first passage and on the side of the first pump is the port injection valve side. And a check valve that opens when the fuel pressure on the first pump side is less than or equal to the fuel pressure on the port injection valve side when the fuel pressure is higher than the fuel pressure of A fuel supply device having a second pump that pressurizes the fuel on the port injection valve side and supplies it to a second passage to which the in-cylinder injection valve is connected;
A control device for controlling the engine and the fuel supply device;
A car comprising:
The control device controls the first pump so that the fuel pressure of the fuel supplied to the port injection valve becomes a target fuel pressure,
Further, when the starting actual fuel pressure, which is the actual fuel pressure of the fuel supplied to the port injection valve at the start of fuel supply to the engine, is higher than the target fuel pressure, the control device supplies the fuel to be supplied to the port injection valve. The first pump is controlled so that the fuel pressure of is gradually changed from the starting actual fuel pressure toward the target fuel pressure at a predetermined rate value ,
The predetermined rate value is such that when the first pump is controlled so that the fuel pressure of the fuel supplied to the port injection valve becomes the target fuel pressure, the fuel pressure on the first pump side of the check valve is the check valve. It is set to be higher than the fuel pressure on the port injection valve side of the valve,
Automobile.

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