JP2006348878A - Fuel injection control device and fuel injection control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce noise in fuel injection inhibiting control in an engine equipped with a plurality of high-pressure fuel pumps. <P>SOLUTION: A fuel injection controller of the invention, when cylinder cut-off control of one side bank is performed by fuel cut, stops driving the high-pressure fuel pump 33 corresponding to the bank of the cylinder cut-off target by disengaging an electromagnetic clutch 45. It is therefore possible to eliminate operation noise upon opening and closing of a solenoid spill valve 36 of the high-pressure fuel pump 33 stopped and operation noise between a cam 44 and a plunder 37 and the noise in the fuel injection inhibiting control can be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel injection control device and a fuel injection control method for performing fuel injection control to a cylinder of an engine by increasing a pressure of fuel supplied from a fuel tank (hereinafter referred to as “fuel pressure”) with a fuel pump.

  Some vehicles employ a so-called direct injection engine that directly injects fuel supplied from a fuel tank into a combustion chamber of a cylinder for the purpose of improving fuel consumption (see, for example, Patent Document 1).

  In such a direct injection engine, in particular, the combustion chamber has a high pressure. Therefore, a high fuel pressure is required to inject fuel against the pressure. For this reason, the fuel supplied from the fuel tank is pressurized by a high-pressure fuel pump, and the regulated fuel is pumped to the combustion chamber.

FIG. 5 is an explanatory diagram showing a schematic configuration of such a conventional fuel injection system.
The high-pressure fuel pump 101 includes a pressurizing chamber 103 formed in the body 102, an electromagnetic valve 105 that opens and closes an introduction port of fuel supplied from the fuel tank 104 to the pressurizing chamber 103, and a cam 106. And a plunger 107 that reciprocates and adjusts the fuel pressure of the fuel introduced into the pressurizing chamber 103. The fuel whose fuel pressure is increased in the pressurizing chamber 103 is pumped to the fuel injection valve 108 at a predetermined timing, and is injected and supplied into the combustion chamber.
JP 2000-54926 A

  However, since the pressure of the fuel to be handled is high in such a high-pressure fuel pump 101, an operation sound when the electromagnetic valve 105 provided at the inlet of the pressurizing chamber 103 opens and closes (particularly when the electromagnetic valve 105 is closed). Impact noise) and noise due to operation sound when the plunger 107 reciprocates by the cam 106 (particularly, operation sound when the plunger 107 is pushed up against the fuel pressure) have arisen.

  That is, since the engine operating sound such as the combustion sound of the air-fuel mixture is loud when the engine is operating, the driver rarely feels the continuous operating sound of the solenoid valve 105 unpleasant. However, when the vehicle shifts to fuel injection suppression control that temporarily executes fuel cut, such as so-called idle-on fuel cut control, maximum speed limiter control, and eco-run control, the engine operating noise is reduced. For this reason, the operation sound of the solenoid valve 105 and the plunger 107 becomes relatively loud, and the driver's discomfort caused by this becomes impossible.

  The present invention has been made in view of these points, and provides a fuel injection control device and a fuel injection control method capable of reducing noise during fuel injection suppression control in an engine equipped with a plurality of high-pressure fuel pumps. The purpose is to do.

  In the present invention, in order to solve the above problems, fuel injection to each cylinder is performed in an engine equipped with at least two high-pressure fuel pumps that increase the fuel pressure of fuel supplied from a fuel tank and pump the fuel pressure toward a fuel injection valve. A fuel injection control device for controlling a reduction cylinder control means capable of executing a fuel cut for at least one of the cylinders, and when the fuel cut by the reduction cylinder control means is executed, the fuel cut There is provided a fuel injection control device comprising pump drive stop means for stopping the drive of a high-pressure fuel pump corresponding to a cylinder.

In such a fuel injection control device, when the fuel cut is executed for any of the cylinders, the driving of the high-pressure fuel pump corresponding to the cylinder subjected to the fuel cut is stopped.
Further, in the present invention, fuel injection control for controlling fuel injection to each cylinder in an engine equipped with at least two high-pressure fuel pumps that increase the fuel pressure of the fuel supplied from the fuel tank and pump the fuel pressure toward the fuel injection valve. A cylinder reduction control step for executing fuel cut on at least one of the cylinders, and when the fuel cut is executed, driving of the high-pressure fuel pump corresponding to the fuel cut cylinder is stopped. There is provided a fuel injection control method comprising a pump drive stop step.

  In such a fuel injection control method, when a fuel cut is executed for any one of the cylinders, the drive of the high-pressure fuel pump corresponding to the fuel-cut cylinder is stopped.

  According to the fuel injection control device and the fuel injection control method of the present invention, since the drive of the high-pressure fuel pump corresponding to the fuel-cut cylinder is stopped, the operation noise of the stopped high-pressure fuel pump can be eliminated, Noise during fuel injection suppression control can be reduced.

  At this time, since the high-pressure fuel pump whose driving is stopped corresponds to the cylinder where the fuel is cut, the behavior of the cylinder on the side where the fuel injection control is continued is not affected.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
In the present embodiment, the vehicle control device of the present invention is applied to a vehicle equipped with a V-type 8-cylinder direct injection engine. FIG. 1 is a schematic configuration diagram showing configurations of an engine and an intake / exhaust system according to the present embodiment.

  The engine 1 includes a cylinder block formed in a V shape having a right bank 1R and a left bank 1L. Although not shown, the first cylinder # 1, the third cylinder # 3, the fifth cylinder # 5, the seventh cylinder # 7 are arranged in the right bank 1R, and the second cylinder # 7 is arranged in the left bank 1L. 2nd, 4th cylinder # 4, 6th cylinder # 6, 8th cylinder # 8 are arranged. Then, depending on the state of the vehicle, a reduced-cylinder operation that stops the operation of either the right bank 1R or the left bank 1L is possible.

  An intake pipe 2 is connected to the upstream side of the intake and exhaust system of the engine 1, and an exhaust pipe 3 is connected to the downstream side. An air cleaner 4 is provided at the upstream end of the intake pipe 2, and an intake manifold 5 that divides the intake passage for each cylinder in the right bank 1 </ b> R and the left bank 1 </ b> L is provided at the downstream end thereof. The air introduced into the intake pipe 2 via the air cleaner 4 is sucked into each cylinder of each bank through each intake manifold 5. Since the right bank 1R and the left bank 1L are arranged symmetrically in the engine 1 and have substantially the same configuration, the same components are denoted by the same reference numerals and the description thereof is simplified.

  A surge tank 6 is provided at an intermediate portion of the intake pipe 2, and a bypass passage 8 is formed so as to bypass the throttle valve 7 disposed slightly upstream. An idle speed control valve (hereinafter referred to as “ISCV”) 9 for adjusting the flow rate of air to be bypassed is disposed in the bypass passage 8. During idling, the engine speed is adjusted by controlling the opening of the ISCV 9 to adjust the intake air amount.

  A fuel injection valve 11 is disposed in the combustion chamber 10 of each cylinder. The fuel injection valve 11 is supplied with fuel that has been pumped from the fuel tank and pressure-regulated, and is opened by energization control to inject fuel into the combustion chamber 10. The fuel injected at this time is mixed with intake air introduced into the combustion chamber 10 from the upstream side via the intake valve 12 to become an air-fuel mixture, and burned to generate engine torque. The details of the configuration and operation of the fuel injection system including the fuel injection valve 11 will be described later.

  Further, a spark plug 13 is arranged in each combustion chamber 10 of each cylinder. The spark plug 13 is applied with a high voltage generated by an ignition device integrated with an ignition coil 14 to generate a spark for ignition. By this ignition, the air-fuel mixture in the combustion chamber 10 burns, and a rotational driving force is applied to the crankshaft 16 via the piston 15. When the engine 1 is in a predetermined high load state, both the right bank 1R and the left bank 1L are operated to generate a large rotational driving force. On the other hand, when the engine 1 is in a predetermined low load state, the reduced cylinder operation is performed. Thus, the fuel cut to all cylinders of one bank is executed and the operation is stopped to improve the fuel consumption. Exhaust gas generated by the combustion is discharged from each cylinder through the exhaust valve 17.

  The exhaust pipe 3 is branched on the upstream side, and an exhaust manifold is connected to the exhaust pipe 3 by joining the exhaust passages of the respective cylinders of the right bank 1R and the left bank 1L to the upstream ends thereof. 18 are provided. A catalytic converter 19 for purifying exhaust gas is disposed downstream of the junction of the exhaust pipe 3. The catalytic converter 19 accommodates a three-way catalyst that simultaneously promotes oxidation of unburned components in the exhaust gas and reduction of nitrogen oxides. Exhaust gas discharged from the combustion chamber 10 is led to the exhaust pipe 3 through the exhaust manifold 18, purified by the catalytic converter 19, and sent to a muffler (not shown).

  An air flow meter 21 integrated with an intake air temperature sensor is provided at the most upstream part of the intake pipe 2 so that the intake air amount and the intake air temperature can be detected. A throttle opening sensor 22 for detecting the opening of the throttle valve 7 is provided in the vicinity of the throttle valve 7 of the intake pipe 2.

  Further, the cylinder block of the engine 1 is provided with a water temperature sensor 23 for detecting the temperature of the engine coolant and a knock sensor 24 for detecting knocking for each bank. Further, a crank angle sensor 25 that generates a crank angle signal at every predetermined crank angle accompanying the rotation of the crankshaft 16 is disposed in the vicinity of the crankshaft 16 in order to calculate the engine speed.

  Further, an air-fuel ratio sensor 26 is provided in the exhaust pipe 3, and fuel injection control is performed by air-fuel ratio feedback control that brings the air-fuel ratio detected by the air-fuel ratio sensor 26 closer to the theoretical air-fuel ratio.

Various types of control including the engine 1 are controlled by an electronic control unit (hereinafter referred to as “ECU”) mounted on the vehicle.
The ECU 20 includes a CPU (Central Processing Unit) that executes various arithmetic processes, a ROM (Read Only Memory) that stores various control arithmetic programs and data, and a RAM (Random Access) that stores numerical values and flags of arithmetic processes in a predetermined area. Memory), EEPROM (Electronically Erasable and Programmable Read Only Memory) that is a non-volatile storage device that stores the results of arithmetic processing, and A / D (Analog / Digital) converter that converts an input analog signal into a digital signal , An input / output interface for inputting / outputting various digital signals, a bus line to which these devices are connected, and the like.

  The ECU 20 takes in output signals from various sensors that detect the state of the engine 1 and outputs drive signals to various actuators provided in the engine 1. That is, in addition to the air flow meter 21, the throttle opening sensor 22, the water temperature sensor 23, the knock sensor 24, the crank angle sensor 25, and the air / fuel ratio sensor 26, the ECU 20 includes an intake pipe that detects the pressure in the intake pipe 2. Sensors and switches such as an atmospheric pressure sensor, a vehicle speed sensor that detects the vehicle speed from the rotation of the vehicle drive shaft, and an ignition switch are connected.

  Further, the ECU 20 includes a fuel injection valve 11 and an ignition device 14 for each cylinder (# 1 to # 8) of each bank, a high pressure fuel pump that regulates the fuel pumped up from the fuel tank and pumps the fuel to the fuel injection valve 11 and a throttle. Various actuators such as a throttle drive motor for opening and closing the valve 7 and a starter motor for cranking the engine 1 are connected.

The ECU 20 performs predetermined vehicle control processing including fuel injection control, which will be described later, according to a control program stored in the ROM.
Next, the configuration and operation of the fuel injection system of the present embodiment will be described. FIG. 2 is an explanatory diagram showing a schematic configuration of the fuel injection system.

  In this fuel injection system, a fuel tank 31 for storing fuel, a feed pump 32 for sending fuel from the fuel tank 31, and pressurizing the fuel supplied from the fuel tank 31 to increase its fuel pressure, And a high-pressure fuel pump 33 that pumps toward the tank. In the present embodiment, the two high-pressure fuel pumps 33 that are in charge of the right bank 1R and the left bank 1L described above are provided, but in the same drawing, for convenience of explanation, the high-pressure fuel pump on the right bank 1R side is provided. Only 33 is shown.

  The high-pressure fuel pump 33 reciprocates in the axial direction with a pressurizing chamber 34 into which fuel supplied from the fuel tank 31 is introduced, and an electromagnetic spill valve 36 that opens and closes the fuel inlet 35 of the pressurizing chamber 34. A plunger 37 that adjusts the fuel pressure of the fuel by changing the volume of the pressure chamber 34 is provided. The pressurizing chamber 34 is connected to the feed pump 32 via a low-pressure pipe 38 and is connected to each fuel injection valve 11 via a high-pressure pipe 39 and a delivery pipe 40.

  The electromagnetic spill valve 36 has a valve body 41 driven by a solenoid, and opens and closes the valve body 41 by moving the valve body 41 in and out of contact with the fuel introduction port 35. The electromagnetic spill valve 36 is energized and controlled by the ECU 20. When the energization of the solenoid is stopped, the electromagnetic spill valve 36 is opened and the low pressure pipe 38 and the pressurizing chamber 34 are in communication with each other.

  The plunger 37 has one end facing the pressurizing chamber 34 and the other end provided with a drive unit 42 exposed to the outside. A cam 44 pivotally supported by the camshaft 43 is in contact with the drive unit 42. The camshaft 43 is configured to be connectable to a connecting shaft (power source of the high-pressure fuel pump 33) connected to the crankshaft 16 via an electromagnetic clutch 45 driven by the ECU 20. When the camshaft 43 is rotated by the connection of the electromagnetic clutch 45, the plunger 37 reciprocates along the cam surface of the cam 44 to adjust the fuel pressure in the pressurizing chamber 34. On the other hand, when the electromagnetic clutch 45 is separated by the ECU 20, the operation of the plunger 37 is stopped and the driving of the high-pressure fuel pump 33 is stopped.

  The pressurizing chamber 34 communicates with the high-pressure pipe 39 via the check valve 46. When the fuel in the pressurizing chamber 34 is pressurized and reaches a predetermined fuel pressure, the check valve 46 is opened and the pressure-adjusted fuel is pumped to the delivery pipe 40 via the high-pressure pipe 39.

  The delivery pipe 40 is provided with a fuel pressure sensor 47 for detecting the pressure of the internal fuel. The delivery pipe 40 is in communication with the fuel tank 31 via a check valve 48 and a return pipe 49. When the fuel pressure detected by the fuel pressure sensor 47 becomes excessively high, the check valve 48 is opened and the fuel in the delivery pipe 40 flows out to the fuel tank 31. Further, the return pipe 49 is connected to a clearance portion 51 provided in the central portion in the axial direction of the plunger 37 via a communication passage 50, and when high-pressure fuel leaks through the sliding portion of the plunger 37. In addition, this is allowed to flow out to the fuel tank 31.

  In such a high-pressure fuel pump 33, the rotation of the cam 44 moves the plunger 37 to the side of increasing the volume of the pressurizing chamber 34, and introduces the fuel sent from the feed pump 32 into the pressurizing chamber 34. Then, the electromagnetic spill valve 36 is closed, the plunger 37 is moved to the side of reducing the volume of the pressurizing chamber 34 to pressurize the internal fuel, and the fuel whose fuel pressure is increased is pumped toward the fuel injection valve 11. To do.

  Thus, the fuel sent out from the feed pump 32 is pressurized by the high-pressure fuel pump 33, and the pressure-adjusted fuel is sent to the fuel injection valve 11 at this time, so that the pressure in the combustion chamber 10 becomes high. In contrast, fuel can be directly injected and supplied. In addition, the pumping of fuel from the high-pressure fuel pump 33 opens the electromagnetic spill valve 36 and separates the electromagnetic clutch 45 to move the plunger 37 to the side of increasing the volume of the pressurizing chamber 34. Can be stopped by.

  Note that the configuration and operation of the high-pressure fuel pump 33 on the left bank 1L side are substantially the same as those of the high-pressure fuel pump 33 on the right bank 1R side described above, and a description thereof will be omitted.

Next, the fuel injection control method of this embodiment will be described. FIG. 3 is a flowchart showing the flow of fuel injection control processing executed by the ECU during the cylinder reduction control.
The fuel injection control of the present embodiment has a main feature in the control at the time of transition from the normal operation to the reduced-cylinder operation by the fuel cut, and the other control is the same as the general fuel injection control. Therefore, in the following, the fuel injection control at the time of switching between the reduced cylinder operation and the normal operation will be mainly described. Here, a description will be given by taking as an example a scene in which the reduced cylinder control is executed to improve fuel efficiency when the vehicle is in a low load state. Hereinafter, the flow of this process will be described using step numbers (hereinafter referred to as “S”).

  The ECU 20 first determines whether or not a predetermined cylinder reduction condition for shifting from normal operation to cylinder reduction operation is satisfied (S1). Although this cylinder reduction condition is set in advance, for example, it can be made a condition that the state has shifted from the normal operation state to the idle state. Specifically, the throttle opening obtained from the output of the throttle opening sensor 22 is zero, and the engine speed calculated based on the output of the crank angle sensor 25 is a predetermined value or more. can do.

  If it is determined that this cylinder reduction condition is satisfied (S1: YES), the cylinder reduction control by fuel cut is executed for all the cylinders in one bank (in this embodiment, the right bank 1R) (S2). At this time, energization to the electromagnetic spill valve 36 of the high-pressure fuel pump 33 corresponding to the right bank 1R is stopped to stop its driving (S3). Subsequently, the electromagnetic clutch 45 that operates the plunger 37 of the high-pressure fuel pump 33 is separated (S4). Accordingly, the driving of the high pressure fuel pump 33 on the side to be reduced is stopped almost simultaneously with the reduction of the cylinder in one bank.

  On the other hand, if it is determined in S1 that the reduced cylinder condition is not satisfied (S1: NO), then it is determined whether or not a predetermined return condition for returning from the reduced cylinder operation to the normal operation is satisfied. (S5). The return condition is also set in advance. For example, a condition can be set when at least one of the above-described reduction cylinder conditions is not satisfied from the reduced cylinder operation state. At this time, if the return condition is not satisfied (S5: NO), the process is terminated and the reduced-cylinder operation is continued.

  If it is determined in S5 that the return condition is satisfied (S5: YES), the cylinder reduction control of the right bank 1R is canceled and the fuel injection to each cylinder is restarted (S6). Then, the separated electromagnetic clutch 45 is coupled (S7), the drive by energizing the electromagnetic spill valve 36 is permitted, and the normal operation is resumed (S8).

In the present embodiment, the ECU 20 corresponds to a fuel injection control device including a reduced cylinder control unit and a pump drive stop unit.
As described above, in the fuel injection control device of the present embodiment, when the cylinder reduction control of one side bank is performed by fuel cut, the high-pressure fuel corresponding to the bank (right bank 1R) that is the target of cylinder reduction. The drive of the pump 33 is stopped. For this reason, it is possible to eliminate the operation sound when the electromagnetic spill valve 36 of the stopped high-pressure fuel pump 33 is opened and closed, and the operation sound between the cam 44 and the plunger 37, thereby reducing the noise during the fuel injection suppression control. be able to.

  At that time, the drive is stopped by the high-pressure fuel pump 33 subject to reduction of the cylinder due to the fuel cut, so that the behavior of the vehicle is stabilized without affecting the fuel injection control that is continued during the reduced-cylinder operation. Can be held in.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. This embodiment is the same as the first embodiment except that the configuration for stopping the drive of the high-pressure fuel pump is different. For this reason, the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted. FIG. 4 is an explanatory diagram showing a schematic configuration of a fuel injection system according to the second embodiment.

  In this fuel injection system, a plunger 237 for adjusting the fuel pressure by changing the volume of the pressurizing chamber 34 is reciprocated in the axial direction by a position variable device 250 provided separately from the cam 44, and the cam 44 It is comprised so that a movement to the position away from was possible. On the other hand, the camshaft 243 that pivotally supports the cam 44 is not connected to the connecting / releasing means such as the electromagnetic clutch 45 shown in FIG. 2, but is connected to the connecting shaft (the power of the high-pressure fuel pump 33) connected to the crankshaft 16. Source: not shown) is directly connected.

  That is, the drive unit 242 provided at the end of the plunger 237 extends in one direction on a plane parallel to the camshaft 243, and its tip is supported by the position variable device 250. The position variable device 250 has a drive shaft 251 that is driven in the axial direction by a solenoid, and the tip of the drive shaft 251 is in contact with the tip of the drive unit 242. When the solenoid is energized and driven by the ECU 20, the drive shaft 251 operates and the plunger 237 can be driven in the axial direction via the drive unit 242 independently of the cam 44. . The illustrated state represents a state in which the plunger 237 is displaced to the top dead center by the position variable device 250. The top dead center position by the position varying device 250 is slightly higher than the top dead center position by the cam 44, and the plunger 237 is separated from the cam 44 so that the rotation of the cam 44 is not transmitted. Accordingly, when the plunger 237 is fixed at the top dead center position by the position variable device 250, the cam 44 is idled, and the operation of the high-pressure fuel pump 233 is substantially stopped. On the other hand, the bottom dead center position of the drive shaft 251 of the position variable device 250 is slightly lower than the bottom dead center position by the cam 44. For this reason, while the high-pressure fuel pump 233 is being driven, the plunger 237 is driven by the cam 44 without being affected by the position variable device 250.

  When the high pressure fuel pump 233 is returned from the operation stop state, the ECU 20 controls the position variable device 250 so that the cam 44 is lowered from its top dead center (that is, the cam crest of the cam 44 is lowered). The plunger 237 is brought into contact with the cam 44. Thus, the plunger 237 can smoothly resume its operation without receiving an impact from the cam 44 at the time of return.

  The operation of the fuel injection control apparatus according to the present embodiment is substantially the same as that of the first embodiment except that the means for stopping the drive of the high-pressure fuel pump 233 is different, so that the description thereof is omitted.

In the present embodiment, the ECU 20 corresponds to a fuel injection control device including a reduced cylinder control means, a pump drive stop means, and a pump drive control means.
As described above, also in the fuel injection control device of the present embodiment, when the cylinder reduction control of the one-side bank is performed by the fuel cut, the driving of the high-pressure fuel pump 233 corresponding to the bank to be reduced is performed. Is stopped. For this reason, it is possible to eliminate the operation sound when the electromagnetic spill valve 36 of the stopped high-pressure fuel pump 233 is opened and closed and the operation sound between the cam 44 and the plunger 237, thereby reducing the noise during the fuel injection suppression control. be able to.

  At that time, the drive is stopped by the high-pressure fuel pump 233 that has been subject to reduction of the cylinder due to the fuel cut, so that the fuel injection control continued during the reduced-cylinder operation is not affected and the vehicle behavior is stabilized. Can be held in.

  In each of the above embodiments, one mode of the configuration for stopping the driving of the high-pressure fuel pump has been described. However, the driving of the high-pressure fuel pump may be stopped by other configurations. For example, the cam abutting on the plunger is configured to be shiftable in the axial direction of the camshaft, and when the high-pressure fuel pump is stopped, the cam is disengaged from the plunger drive unit. Various modifications can be employed.

  In each of the above-described embodiments, two banks, the right bank 1R and the left bank 1L, and two high-pressure fuel pumps corresponding to each bank are provided, and the cylinder on the right bank 1R side is fuel cut when the number of cylinders is reduced. Thus, the operation of the high-pressure fuel pump corresponding to this is stopped. However, the left bank 1L side may be controlled to be reduced and the operation of the high-pressure fuel pump corresponding thereto may be stopped. Further, when three or more banks are provided, the fuel of one of the banks may be cut when the number of cylinders is reduced, and the operation of the high-pressure fuel pump corresponding thereto may be stopped. Alternatively, fuel cut to all cylinders connected to any one high-pressure fuel pump may be preferentially executed so that the corresponding high-pressure fuel pump can be easily stopped.

  In each of the above embodiments, a high-pressure fuel pump is provided for each of a plurality of banks, and a vehicle that shifts to a reduced-cylinder operation by stopping one bank when a predetermined reduced-cylinder condition is satisfied has been described. The fuel injection control method of the present invention can also be applied to a vehicle that does not perform such reduced cylinder control. In other words, regardless of the bank, each of a plurality of high-pressure fuel pumps is responsible for supplying fuel to one or a plurality of specific cylinders, and is applied to a vehicle in which cylinder reduction control by fuel cut is performed in any one of the cylinders. can do. In that case, the drive of the high-pressure fuel pump in charge of the cylinder to be reduced is stopped.

  Further, in each of the above embodiments, the present invention is applied to a vehicle equipped with a V-type 8-cylinder direct injection engine. However, the present invention is applied to a vehicle equipped with another type of engine such as an in-line 4-cylinder engine. Of course, you may do. In the case of in-line four cylinders, one high-pressure fuel pump is in charge of any cylinder and the remaining cylinders, and the high-pressure fuel pump in charge of the cylinder to be reduced is stopped during the cylinder reduction control. It is good to make it. However, the effect of the present invention can be remarkably exhibited when applied to an engine in which the fuel pressure during fuel injection control is increased, such as a direct injection engine.

It is a schematic block diagram showing the structure of the engine and intake / exhaust system which concerns on 1st Embodiment. It is explanatory drawing showing schematic structure of a fuel-injection system. It is a flowchart showing the flow of the process of the fuel injection control which ECU performs in the time of cylinder reduction control. It is explanatory drawing showing schematic structure of the fuel-injection system which concerns on 2nd Embodiment. It is explanatory drawing showing schematic structure of the conventional fuel-injection system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 1R Right bank 1L Left bank 10 Combustion chamber 11 Fuel injection valve 12 Intake valve 14 Ignition device 16 Crankshaft 17 Exhaust valve 25 Crank angle sensor 31 Fuel tank 32 Feed pump 33,233 High pressure fuel pump 34 Pressurization chamber 35 Fuel introduction Port 36 Electromagnetic spill valve 37, 237 Plunger 41 Valve body 42, 242 Drive unit 43, 243 Cam shaft 44 Cam 45 Electromagnetic clutch 250 Position variable device 251 Drive shaft

Claims (7)

A fuel injection control device that controls fuel injection to each cylinder in an engine equipped with at least two high-pressure fuel pumps that increase the fuel pressure of fuel supplied from a fuel tank and pump the fuel pressure toward a fuel injection valve,
A cylinder reduction control means capable of performing fuel cut on at least one of the cylinders;
Pump drive stop means for stopping the drive of the high-pressure fuel pump corresponding to the cylinder from which the fuel was cut when fuel cut by the reduced cylinder control means is executed;
A fuel injection control device comprising: The high-pressure fuel pump is configured by disposing a clutch with a power source of the high-pressure fuel pump,
2. The fuel injection control device according to claim 1, wherein the pump drive stop means stops the drive of the high-pressure fuel pump by performing separation control of the clutch. The high-pressure fuel pump is reciprocated by rotation of a cam, and a pressurizing chamber into which fuel supplied from the fuel tank is introduced, a valve for opening and closing the fuel inlet of the pressurizing chamber, and the pressurization. A plunger for adjusting the fuel pressure of the fuel in the room,
The plunger is driven in the reciprocating direction by a position variable device separately from the cam, and is configured to be movable to a position separated from the cam.
2. The fuel injection control device according to claim 1, wherein the pump drive stop unit controls the position variable device to stop the operation of the high-pressure fuel pump by separating the plunger from the cam. 3. A pump drive control means for returning the drive of the high-pressure fuel pump from a stopped state;
4. The fuel injection control device according to claim 3, wherein the pump drive control means controls the variable position device so that the plunger is brought into contact with the cam at a timing when the cam is lowered from the top dead center. A fuel injection control device that controls fuel injection to each cylinder in an engine equipped with at least two high-pressure fuel pumps that increase the fuel pressure of fuel supplied from a fuel tank and pump the fuel pressure toward a fuel injection valve,
A fuel injection control device that performs fuel cut by giving priority to a cylinder that supplies fuel using any one high-pressure fuel pump. A fuel injection control method for controlling fuel injection into each cylinder in an engine equipped with at least two high-pressure fuel pumps that increase the fuel pressure of fuel supplied from a fuel tank and pump the fuel pressure toward a fuel injection valve,
A cylinder reduction control step for executing fuel cut for at least one of the cylinders;
A pump drive stop step for stopping the drive of the high-pressure fuel pump corresponding to the fuel-cut cylinder when the fuel cut is performed;
A fuel injection control method comprising: A fuel injection control method for controlling fuel injection into each cylinder in an engine equipped with at least two high-pressure fuel pumps that increase the fuel pressure of fuel supplied from a fuel tank and pump the fuel pressure toward a fuel injection valve,
A fuel injection control method, wherein priority is given to a cylinder that supplies fuel using any one high-pressure fuel pump, and fuel cut is executed.

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