JP4054789B2 - In-cylinder injection engine control device - Google Patents

Description

  The present invention relates to a high pressure fuel pump control device and an in-cylinder injection engine control device, and more particularly to a high pressure fuel pump control device and an in-cylinder injection engine that control the operation of a high pressure fuel pump that pumps high pressure fuel to a common rail of a fuel injection valve. The present invention relates to a control device.

  Current automobiles are required to reduce exhaust gas substances such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) contained in automobile exhaust gas from the viewpoint of environmental conservation. In order to reduce this, a direct injection engine (in-cylinder injection engine) has been developed. The in-cylinder injection engine performs fuel injection by a fuel injection valve directly in a combustion chamber of a cylinder, and reduces the particle size of fuel injected from the fuel injection valve to burn the injected fuel. To reduce exhaust gas substances and improve engine output.

  Here, in order to reduce the particle size of the fuel injected from the fuel injection valve, means for increasing the pressure of the fuel is required, and the technology of the high-pressure fuel pump that pumps high-pressure fuel to the fuel injection valve Have been proposed (see, for example, Japanese Patent No. 2690734, Japanese Patent Laid-Open No. 10-153157, etc.).

  The technology of Patent No. 2690734 relates to a variable discharge high pressure pump that pumps high pressure fuel into a common rail (an oil storage passage common between cylinders) of a fuel injection device, and the variable discharge high pressure pump is a cylinder. A plunger built in the cylinder and driven by the engine, a pressurization chamber formed by the upper end surface of the plunger and the inner peripheral surface of the cylinder, and facing the pressurization chamber and fixed to the cylinder The solenoid valve is configured to close the low-pressure passage communicating with the pressurizing chamber by energizing the solenoid valve, and further, the fuel in the pressurizing chamber is boosted and pumped to the common rail by the raising of the plunger. The amount of fuel discharged to the common rail is adjusted by opening and closing the solenoid valve.

  Further, the technique disclosed in Japanese Patent Laid-Open No. 10-153157 relates to a variable discharge high pressure pump that adjusts the amount of fuel supplied to the engine by a fuel spill valve that is an electromagnetic valve. A cylinder, a plunger built in the cylinder, and a pressurization chamber formed by an upper end surface of the plunger and an inner peripheral surface of the cylinder. In the pressurization chamber, fuel is supplied from a low-pressure feed pump. An inflow passage through which the fuel is fed, a supply passage for pumping high-pressure fuel to the common rail, and a spill passage communicating with a fuel spill valve that returns fuel (spill) overflowing from the pressurizing chamber to the fuel tank are connected to each other, and the fuel spill The amount of fuel discharged to the common rail is adjusted by opening and closing the valve.

Patent No. 2690734 JP-A-10-153157

  By the way, the prior art of the said patent number 2690734 has the electromagnetic valve which opens and closes the said common rail in order to suppress generation | occurrence | production of the vapor lock by the significant reduction of the pressure in the said pressurization chamber in the suction stroke of the said plunger. When the maximum flow rate is discharged from the pressurizing chamber, there is a loss of pressurization time due to a delay in closing the solenoid valve when the plunger moves to the compression stroke. When the fuel discharge capacity is reduced and a small flow rate is discharged from the pressurizing chamber, the plunger needs to spend most of the compression stroke to maintain the open state of the solenoid valve. There is a problem in that the solenoid valve must be opened and closed within a short time between the suction stroke and the compression stroke.

  In the prior art disclosed in JP-A-10-153157, the inflow passage and the spill passage are provided separately, and the intake stroke of the plunger and the opening and closing of the spill valve are independent of the inflow of fuel. Therefore, although the above problem has been solved, in addition to the increase in the size of the variable discharge high pressure pump by providing the spill passage, two points for the intake valve of the inflow passage and the spill valve of the spill passage are provided. Since it requires a valve seat and also requires improvement in valve seat processing accuracy in order to prevent the discharge capacity from being lowered due to leakage from the valve seat, the manufacturing cost increases, and while the spill valve is closed, Since the current must be continuously energized, there is a disadvantage that the power consumption increases. Furthermore, each of the conventional techniques must completely synchronize the operation of the solenoid valve with the reciprocating stroke of the plunger, and high response of the solenoid valve and high accuracy of the synchronization signal are required. There is a problem that the system becomes very expensive.

  Here, the present applicant has studied in order to solve the above problems, and has proposed various inventions of variable discharge high pressure pumps as previous applications. For example, the present invention reciprocates as the cam rotates. Due to the volume change in the pressurizing chamber by the plunger, the pressure on the downstream side of the suction valve (the pressurization chamber side) in the inflow passage is equal to or higher than the pressure on the upstream side of the suction valve (the inflow passage side) In this case, by providing a valve closing spring that urges the intake valve to close, the intake valve is closed and the intake valve is urged to open. There is a technology of a variable discharge high pressure pump that has a push rod provided with a spring and operates the push rod by energization / non-energization of a solenoid. The suction valve is separated from the electromagnetic valve, the suction valve and the push rod are separated, and the problem is solved by a configuration in which the valve seat is not provided in two places. .

  By the way, an operation timing chart from the start of the engine by the variable discharge high-pressure pump is shown in FIG. 22, and a crank angle signal is determined by starting cranking from the engine start and driving a plunger. The solenoid control signal cannot be output during the time until the plunger phase is determined, and the first solenoid control signal is output based on the REF signal only after the plunger phase is determined. It can be seen that the fuel injection valve has the fuel pressure 22b when the high pressure fuel is pumped to increase the fuel pressure and the second solenoid control signal is output and the fuel is pumped to the common rail.

  Therefore, as shown in FIG. 22, for example, even when the plunger is moving from the stop position 22a to the compression stroke through the bottom dead center during the time until the plunger phase is determined, the intake valve Therefore, the fuel pressure cannot be increased for this time, and a time delay until the target fuel pressure is reached occurs. This causes a problem that the engine start time is prolonged and the atomization of the spray particle diameter by the fuel injection valve is also delayed, which greatly affects the HC emission amount.

  Therefore, the present inventor needs to control the high-pressure fuel pump so that the high-pressure fuel can be pumped to the common rail from the start of cranking to the determination of the plunger phase with the cam angle signal. However, none of the conventional techniques give special consideration to the promotion of an increase in fuel pressure from the start of the engine.

  The present invention has been made in view of such problems. The object of the present invention is to increase the fuel pressure from the start of the engine by the high pressure fuel pump, shorten the engine start time, and reduce the exhaust gas. To provide a high-pressure fuel pump control device and an in-cylinder injection engine control device capable of reducing substances and improving engine output.

In order to achieve the above object, an in-cylinder injection engine control device according to the present invention includes a fuel injection valve provided in a cylinder, a high-pressure fuel pump that pumps fuel to the fuel injection valve, and a position of a crankshaft of the cylinder. In the in- cylinder injection engine control apparatus for controlling the in-cylinder injection engine having a crank angle sensor for detecting the pressure , the high-pressure fuel pump is a plunger that pressurizes the fuel in the high-pressure fuel pump by a solenoid driven based on a solenoid signal When a pump drive cam for opening and closing the intake valve or an exhaust valve of the cylinder with driving the plunger, and a cam angle sensor for detecting the position of the pump drive cam, the cylinder injection engine control device , the crank angle sensor, and based on the detection signal from the fuel pressure sensor provided in the fuel injection valve, the solenoid signal A basic angle calculating means for calculating a basic angle, and the target fuel pressure calculating means for calculating a target fuel pressure, the fuel pressure input processing means for outputting actual fuel pressure, is composed of a plurality of different control blocks for controlling the solenoid, the control block Each time, the solenoid control signal calculating means for calculating the reference angle of the solenoid signal based on each of these means from the basic angle , and the state of the in-cylinder injection engine are determined . State transition determining means for performing transition, solenoid driving means for driving the solenoid based on the solenoid signal of the transitioned control block, solenoid operation delay correcting means for correcting an operation delay of the solenoid, and an intake valve for the cylinder Alternatively, valve timing driving means for adjusting the opening / closing timing of the exhaust valve, and the bubble timing Valve timing correction means for correcting the opening / closing timing based on the advance angle of the drive cam by the drive means, and the in-cylinder injection engine control device provides a reference for the solenoid signal by the solenoid control signal calculation means. The angle is corrected by the operation delay of the solenoid and the cam advance angle, and the corrected reference angle of the solenoid signal is output as a final angle to the solenoid driving means. Further, in the in-cylinder injection engine control device according to the present invention, the control block includes the solenoid block from a signal detection timing of the crank angle sensor to a timing at which a phase between the crank angle sensor and the cam angle sensor is determined. It includes at least an equally-spaced energization control block for energizing the solenoid at equal intervals by a signal, and a feedback control block after a complete explosion of the in-cylinder injection engine so that the actual fuel pressure becomes the target fuel pressure. Is more preferable.

  As can be understood from the above description, the high-pressure fuel pump control device and the in-cylinder injection engine control device according to the present invention perform equal interval energization control on the high-pressure fuel pump from detection of the crank angle signal. Therefore, it is possible to promote the fuel pressure and shorten the engine start time.

  Further, since the fuel pressure at the time of fuel injection is promoted, it is possible to reduce the exhaust gas emission amount and improve the engine output.

  Furthermore, fail-safe can be achieved by applying equal-interval energization control to the high-pressure fuel pump not only when starting the engine but also during normal operation.

Hereinafter, an embodiment of a high pressure fuel pump control device and a direct injection engine control device of the present invention will be described with reference to the drawings.
FIG. 1 shows the overall configuration of the control system of the direct injection engine 507 of the present embodiment. The in-cylinder injection engine 507 is composed of four cylinders, and the air introduced into each cylinder 507b is taken from the inlet 502a of the air cleaner 502, passes through an air flow meter (air flow sensor) 503, and is an electric throttle that controls the intake flow rate. The collector 506 is entered through the throttle body 505 in which the valve 505a is accommodated. The air sucked into the collector 506 is distributed to each intake pipe 501 connected to each cylinder 507b of the engine 507, and then guided to a combustion chamber 507c formed by the piston 507a, the cylinder 507b, and the like.

  The airflow sensor 503 outputs a signal representing the intake flow rate to the high-pressure fuel pump control device and the in-cylinder injection engine control device (control unit) 515. Further, the throttle body 505 is provided with a throttle sensor 504 for detecting the opening degree of the electric throttle valve 505a, and the signal is also output to the control unit 515.

  On the other hand, fuel such as gasoline is primarily pressurized from the fuel tank 50 by the fuel pump 51 and regulated to a constant pressure (for example, 3 kg / cm 2) by the fuel pressure regulator 52 and is higher by the high-pressure fuel pump 1 described later. Secondary pressure is applied to a pressure (for example, 50 kg / cm 2), and the fuel is injected into the combustion chamber 507 c from the fuel injection valve (injector) 54 provided in each cylinder 507 b through the common rail 53. The fuel injected into the combustion chamber 507c is ignited by the ignition plug 508 by the ignition signal that has been increased in voltage by the ignition coil 522.

  A crank angle sensor 516 attached to the crankshaft 507d of the engine 507 outputs a signal indicating the rotational position of the crankshaft 507d to the control unit 515, and a cam attached to the camshaft (not shown) of the exhaust valve 526. The angle sensor 511 outputs a reference angle signal representing the rotational position of the cam shaft to the control unit 515 and also outputs a reference angle signal representing the rotational position of the pump drive cam 100 of the high-pressure fuel pump 1 to the control unit 515. Further, the A / F sensor 518 provided upstream of the catalyst 520 in the exhaust pipe 519 detects the exhaust gas, and the detection signal is output to the control unit 515. The camshaft 510 of the intake valve 514 is adjusted for the opening / closing timing of the intake valve 514 via valve timing driving means (not shown).

  As shown in FIG. 2, the main part of the control unit 515 includes an MPU 603, an EP-ROM 602, a RAM 604, an I / O LSI 601 including an A / D converter, etc., and includes a crank angle sensor 516, a cam angle sensor 511, and an engine. The signals from various sensors including the coolant temperature sensor 517 and the fuel pressure sensor 56 are input as inputs, predetermined calculation processing is executed, various control signals calculated as the calculation results are output, the solenoid 200, A predetermined control signal is supplied to each injector 54, ignition coil 522, and the like, and fuel discharge amount control, fuel supply amount control, ignition timing control, and the like are executed.

3 and 4 show the high-pressure fuel pump 1, FIG. 3 shows an overall configuration diagram of a fuel system including the high-pressure fuel pump 1, and FIG. 4 shows a longitudinal section of the high-pressure fuel pump 1. A plane view is shown.
The high-pressure fuel pump 1 pressurizes fuel from the fuel tank 50 and pumps high-pressure fuel to the common rail 53. The high-pressure fuel pump 1 includes a cylinder chamber 7, a pump chamber 8, and a solenoid chamber 9. The cylinder chamber 7 is disposed below the pump chamber 8, and the solenoid chamber 9 is disposed to the right of the pump chamber 8.

  The cylinder chamber 7 includes a plunger 2, a lifter 3, and a plunger lowering spring 4. The plunger 2 is pressed against a pump drive cam 100 that rotates as the cam shaft of the exhaust valve 526 in the engine 507 rotates. The volume of the pressurizing chamber 12 in the pump chamber 8 is changed by reciprocating through the lifter 3.

  The pump chamber 8 includes a low-pressure fuel suction passage 10, a pressurization chamber 12, and a high-pressure fuel discharge passage 11, and a suction valve 5 is provided between the suction passage 10 and the pressurization chamber 12. The intake valve 5 is a check valve that restricts the direction of fuel flow through a valve closing spring 5 a that biases the pump valve 8 toward the solenoid chamber 9 in the valve closing direction. A discharge valve 6 is provided between the pressurizing chamber 12 and the discharge passage 11, and the discharge valve 6 is also urged from the pump chamber 8 toward the solenoid chamber 9 in the valve closing direction of the discharge valve 6. This is a check valve that restricts the flow direction of the fuel via the valve closing spring 6a. The valve closing spring 5a has a pressure on the pressurizing chamber 12 side equal to or higher than the pressure on the inflow passage 10 side across the suction valve 5 due to the volume change in the pressurizing chamber 12 by the plunger 2. In this case, the suction valve 5 is urged to close.

  The solenoid chamber 9 includes a solenoid 200, a suction valve engagement member 201, and a valve opening spring 202. The suction valve engagement member 201 is in contact with the suction valve 5 so that the tip thereof can be contacted and separated. In addition, it is disposed at a position opposite to the suction valve 5 and moves in a direction to close the suction valve 5 when the solenoid 200 is energized. On the other hand, in the state where the energization of the solenoid 200 is released, the suction valve 5 moves in a direction to open the valve via the valve opening spring 202 engaged with the rear end of the suction valve engaging member 201, and the suction valve The valve 5 is opened.

  The fuel adjusted to a constant pressure from the fuel tank 50 via the fuel pump 51 and the fuel pressure regulator 52 is guided to the suction passage 10 of the pump chamber 8, and then the pressure chamber 12 in the pump chamber 8 The plunger 2 is pressurized by the reciprocating motion of the plunger 2 and is pumped from the discharge passage 11 of the pump chamber 8 to the common rail 53.

The common rail 53 is provided with a relief valve 55 and a fuel pressure sensor 56 in addition to each injector 54 provided in accordance with the number of cylinders of the engine. A control unit 515 includes a crank angle sensor 516, a cam angle sensor 511, In addition, a drive signal of the solenoid 200, that is, a solenoid control signal (solenoid signal) is output based on each detection signal of the fuel pressure sensor 56 to control fuel discharge, and a drive signal of each injector 54 is output to generate fuel. The injection is controlled. The relief valve 55 is opened when the pressure in the common rail 53 exceeds a predetermined value to prevent damage to the piping system.

  FIG. 5 shows an operation timing chart of the high-pressure fuel pump 1. The actual stroke (actual position) of the plunger 2 driven by the pump drive cam 100 is a curve as shown in FIG. 6, but in order to make the positions of the top dead center and the bottom dead center easy to understand, The stroke of the plunger 2 is expressed linearly.

  When the plunger 2 moves from the top dead center side to the bottom dead center side according to the biasing force of the plunger lowering spring 4 by the rotation of the cam 100, the suction stroke of the pump chamber 8 is performed. In the suction stroke, the position of the rod, which is the suction valve engaging member 201, is engaged with the suction valve 5 according to the biasing force of the valve opening spring 202 to move the suction valve 5 in the valve opening direction and pressurize. The pressure in the chamber 12 decreases.

  Next, when the plunger 2 moves from the bottom dead center side to the top dead center side against the urging force of the plunger lowering spring 4 by the rotation of the cam 100, the compression stroke of the pump chamber 8 is performed. In the compression stroke, when the drive signal of the solenoid 200 is output from the control unit 515 and the solenoid 200 is energized (ON state), the position of the rod which is the suction valve engaging member 201 is attached to the valve opening spring 202. The suction valve 5 is moved in the valve closing direction against the force, and its tip is disengaged from the suction valve 5, and the suction valve 5 is closed according to the biasing force of the valve closing spring 5a. By moving in the direction, the pressure in the pressurizing chamber 12 increases. Therefore, the suction valve 5 can perform maximum discharge regardless of the responsiveness of the solenoid 200.

  When the suction valve engaging member 201 is most attracted to the solenoid 200 side, the suction valve 5 synchronized with the reciprocation of the plunger 2 is closed, and the pressure in the pressurizing chamber 12 reaches the highest point. The fuel in the chamber 12 presses the discharge valve 6, and the discharge valve 6 is automatically opened against the urging force of the valve closing spring 6a. It is discharged to the common rail 53 side. The solenoid 200 drive signal is turned off (OFF state) when the suction valve engagement member 201 is most attracted to the solenoid 200 side. Therefore, the intake valve 5 is maintained in a closed state, and fuel is discharged to the common rail 53 side. Therefore, high responsiveness of ON-OFF is not required.

  When the plunger 2 moves from the top dead center side to the bottom dead center side according to the biasing force of the plunger lowering spring 4 by the rotation of the cam 100, the suction stroke of the pump chamber 8 is performed, and the pressurizing chamber As the pressure in the valve 12 decreases, the suction valve engaging member 201 is engaged with the suction valve 5 in accordance with the urging force of the valve opening spring 202 and moves in the valve opening direction. The valve automatically opens in synchronism with the reciprocating motion, and the open state of the intake valve 5 is maintained. Then, the discharge valve 6 is not opened due to the pressure drop in the pressurizing chamber 12. Thereafter, the above operation is repeated.

  When the solenoid 200 is turned on during the compression process before the pressure in the pressurizing chamber 12 reaches the highest point, the fuel is fed to the common rail 53 from this time. Since the pressure in the pressurizing chamber 12 has increased once the fuel pumping has started, the suction valve 5 remains closed even if the solenoid 200 is turned off thereafter, while the suction process starts. The valve can be automatically opened in synchronism, and the amount of fuel discharged to the common rail 53 can be adjusted by the ON timing of the solenoid 200. Further, the control unit 515 calculates an appropriate discharge timing based on the signal from the pressure sensor 56 and controls the solenoid 200 to feedback control the pressure of the common rail 53 to the target value.

  FIG. 7 is a control block diagram of the high-pressure fuel pump 1 by the control unit 515. The drive signal setting means 716 of the control unit 515 is similar to the basic angle calculation means 701 for calculating the basic angle of the solenoid signal from the engine speed NDATA and the engine load LDATA based on the operating conditions of the crank angle sensor 516 and the like. A target fuel pressure calculating means 702 for calculating an optimum target fuel pressure for the operating point from the engine speed NDATA and the load LDATA; a fuel pressure input processing means 703 for filtering the signal from the fuel pressure sensor 76 and outputting an actual fuel pressure; Solenoid control signal calculation means 714 for calculating a control signal for the solenoid 200 of the high-pressure fuel pump 1 based on the basic angle calculation means 701, the target fuel pressure calculation means 702 and the fuel pressure input processing means 703, and a cylinder injection engine 507 State transition judgment that makes transition by judging the state A step 710, and a solenoid operation delay correcting means 711 for correcting the operation delay of the solenoid 200 based on the battery voltage; and a phase difference between the crankshaft 507d and the cam shaft based on the advance value of the cam 100 And a solenoid driving means 713 for outputting a driving signal to the solenoid 200 of the high-pressure fuel pump 1. The solenoid control signal calculating means 714 sets the solenoid signal of the solenoid 200 to the reference angle of the solenoid signal. The valve timing correction means in consideration of the influence of the solenoid operation delay correction means 711 in consideration of the fact that the operation delay time varies depending on the battery voltage and the influence of the valve timing drive means on the drive angle of the solenoid 200. 712 The final angle by adding each correction amount by being input to the solenoid driving means 713.

  The solenoid control signal calculation means 714 includes an A control (non-energization control) block 704, a B control (equal interval energization control) block 705, a C control (full discharge control) block 706, a D control (fixed phase control) block 707, The F / B control block 708 and the F / B stop (non-energization control) block 709 are composed of six control blocks, which will be described later, and the transition of each control block is performed by the state transition determination means 710 and the solenoid signal A reference angle is selectively calculated.

  The control unit 515 detects the signal of the cam angle sensor 511 that detects the position of the pump drive cam 100 or the like by disconnection or the like in order to improve the reliability of the high pressure fuel pump control device and the engine control device 515. When it is not possible, a detection signal switching means 715 for switching to a signal of the cam angle sensor of the suction valve 514 or a signal of the crank angle sensor 516 is provided. When none of the signals from the sensors 511 and 516 can be detected, another drive signal setting means 717 for outputting a drive signal to the high pressure fuel pump 1 based on a table stored in the ROM 602 is provided. And fail safe. Further, since the other drive signal setting means 717 cannot detect signals from the sensors 511 and 516 due to disconnection or the like as described above, the engine 507 is also activated when the valve timing drive means is not operating. A drive signal is output to the high-pressure fuel pump 1 in accordance with the above state, and the operation is continued until the valve timing driving means is activated again.

FIG. 8 is a state transition diagram of each control block from the A control block 704 to the F / B stop block 709 in the solenoid control signal calculation means 714.
First, when the ignition switch is turned from OFF to ON and the MPU 603 of the control unit 515 is in a reset state, the A control block 704 becomes a non-energized control state, and the solenoid 200 is not energized.

  Next, when the ignition switch is turned on and the engine 507 is in the cranking state and the crank angle signal CRANK is detected, the condition 1 is satisfied and the state shifts to the equal interval energization control state which is the B control block 705. Here, the B control block 705 detects the pulse of the crank angle signal CRANK, but has not yet recognized the stroke of the plunger 2 as the REF signal, and has not yet performed the crank angle signal CRANK and the cam angle signal CAM. That is, the plunger phase of the high-pressure fuel pump 1 cannot be recognized when the plunger 2 is at the bottom dead center position. In the present embodiment, a B control block 705 (to be described later) is selected, energized at equal intervals, and intermittent solenoid control signals are output.

  Then, when the cranking state enters the middle period from the initial stage, the plunger phases of the crank angle signal CRANK and the cam angle signal CAM are determined, and the REF signal can be recognized, the condition 3 is satisfied and the full discharge which is the C control block 706 is achieved. A transition is made to the control state, and a solenoid control signal is output so that the suction valve 5 is closed from the bottom dead center of the plunger 2.

  Further, when it is recognized that the first explosion occurs in the engine 507 and the engine speed increases without continuing the cranking, the condition 4 is satisfied and the state shifts to the fixed phase control state which is the D control block 707, and the plunger 2 A solenoid control signal is output so that the suction valve 5 is closed when a predetermined angle has elapsed from the bottom dead center. When the engine speed becomes equal to or lower than the predetermined value, the condition 5 is satisfied and the process proceeds to the C control block 706.

  Further, when a predetermined time has elapsed since the complete explosion of the engine 507, the condition 6 is satisfied and the routine proceeds to the F / B control block 708, and the actual fuel pressure calculated by the fuel pressure input processing means 703 is changed to the target fuel pressure calculating means. Feedback control is performed by changing the phase at which the intake valve 5 begins to close so that the target fuel pressure calculated in 702 is reached. Thereafter, the F / B control block 708 continues unless the ignition switch is turned off or an engine stall occurs. However, in the F / B control block 708, when a fuel cut occurs due to vehicle deceleration or the like, fuel injection by the injector 54 is not performed, and there is no decrease in the amount of fuel from the common rail 53, so condition 7 is satisfied. Then, the state transits to the F / B stop block 709, and the fuel pumping from the high pressure fuel pump 1 to the common rail 53 is stopped. From the F / B stop block 709, the condition 8 is satisfied by the end of the fuel cut, and the process shifts to the F / B control block 708 to return to the normal feedback control. When the ignition switch is turned off or an engine stall occurs, Condition 2, Condition 9 to Condition 12 are satisfied, and the process proceeds to the A control block 704.

  FIG. 9 is an operation timing chart of the control unit 515. The control unit 515 detects the top dead center position of each piston 507a based on a detection signal (CAM signal) from the cam angle sensor 511 and a detection signal (CRANK signal) from the crank angle sensor 516, and performs fuel injection control and ignition. While performing the timing control, the stroke of the plunger 2 is detected based on the detection signal (CAM signal) from the cam angle sensor 511 and the detection signal (CRANK signal) from the crank angle sensor 516, and the high pressure fuel pump 1 Solenoid control is performed as fuel discharge control. Note that the stroke of the plunger 2 as the REF signal is generated based on the CRANK signal and the CAM signal as described above.

  Here, the portion of the CRANK signal lacking in FIG. 9 (shown by a dotted line) is a reference position, and a predetermined phase component from the top dead center of CYL # 1 or CYL # 4. It is in a shifted position. Then, when the CRANK signal is missing, the control unit 515 determines whether the CAM signal is CYL # 1 or CYL # 4 depending on whether the CAM signal is Hi or Lo. When the phase of the cam shaft of the intake valve 514 is shifted by the valve timing driving means, the phase of the CAM signal is shifted by VVT with respect to the CRANK signal, as shown by a one-dot chain line and a solid line. Become.

  By the way, in this embodiment, solenoid control is performed with reference to the phase when the cam phase by the valve timing driving means is the most retarded angle (indicated by a one-dot chain line), and the valve timing correction means 712 advances by VVT. A signal is being output. The fuel discharge from the high-pressure fuel pump 1 is started after a lapse of a predetermined time corresponding to the operation delay of the solenoid 200 from the rise of the solenoid signal. On the other hand, the discharge is performed even if the solenoid signal falls. Since the suction valve 5 is pushed by the pressure from 12, the operation continues until the plunger stroke reaches the top dead center.

FIG. 10 shows parameters used for the output start angle STANG and the output end angle ENDANG of the solenoid control signal for the control of the fuel pressure by the control unit 515.
The output start angle STANG and the output end angle ENDANG of the solenoid signal are obtained from the REF signal generated based on the CRANK signal and the CAM signal, the stroke of the plunger 2, and the solenoid control signal. First, the output start angle STANG Can be obtained as shown in Equation 1.

[Equation 1]
STANG = REFANG-CAMADV-PUMRE

Here, REFANG is a basic angle, which is calculated by the basic opening calculation means 701 (FIG. 7) based on the operating state of the engine 507, and CAMADV is a cam advance value, which is an angle of VVT (FIG. 9). Equivalent to. PUMRE is a pump delay angle, which is calculated by a solenoid operation delay correction means 711 (FIG. 7), and represents, for example, an operation delay of the intake valve engagement member 201 based on solenoid energization that varies depending on the battery voltage.
Further, the output end angle ENDANG can be obtained as shown in Equation 2.

[Equation 2]
ENDANG = REFANG-CAMADV + KEPU #

  Here, KEPU # is a pump holding angle and represents a pump energization time. In addition, the pump holding time KEPU # is added to delay the output end angle in the case where it is desired to start the discharge from the bottom dead center of the plunger 2 in the entire discharge of the fuel. Even if the valve engagement member 201 and the suction valve 5 are engaged, the suction valve engagement member 201 is held until the suction valve 5 is closed by the pressure in the pressurizing chamber 12. .

  11 to 13 are timing charts for controlling the high-pressure fuel pump 1 by the control unit 515. First, FIG. 11 is an operation timing chart from the A control block to the B control block in the control unit 515.

  First, the control unit 515 energizes at equal intervals when the ignition switch is turned on from the A control block in the non-energized control state and the engine 507 starts cranking and detects the first crank angle signal CRANK. A transition is made to the B control block that is in the control state, and the B control block outputs a drive signal at least twice to the solenoid 200 of the high-pressure fuel pump 1 while the plunger 2 reciprocates once. Energization is performed, and the solenoid control signal is repeatedly turned on and off continuously. This ON-OFF signal is synchronized with the rise of the crank angle sensor 516 signal at a predetermined cycle MPRINT # (for example, 50 ms). The CRANK is set to an ON period of a predetermined angle (time) MDLWID # (for example, 20 ms). Depending on whether the CAM signal is Hi or Lo when the signal is missing, a REF signal is generated and output until it can be recognized.

  As a result, until the CRANK signal tooth missing portion and the CAM signal are detected, that is, even when the bottom dead center position of the plunger 2 of the high-pressure fuel pump 1 cannot be recognized, the bottom dead center position of the plunger 2 is concerned. First, the maximum discharge amount of the high-pressure fuel to the common rail 53 can be pumped, and the fuel pressure of the injector 54 is increased as much as possible from the time of starting the engine. When the REF signal is recognized, a transition is made to the C control block.

FIG. 12 is an operation timing chart from the B control block to the C control block in the control unit 515.
As described above, when the control unit 515 recognizes the REF signal and determines the plunger phase, the control unit 515 transitions from the B control block to the C control block, which is a full discharge control, and from the recognition of the REF signal, the predetermined output start angle. A solenoid control signal is output so as to sandwich the bottom dead center of the plunger 2 at STANG and the predetermined output end angle ENDANG. When an increase in engine speed is recognized, the process proceeds to the D control block.

  FIG. 13 is an operation timing chart of control from the C control block in the control unit 515.

  When the control unit 515 recognizes an increase in the engine speed, the control unit 515 transitions from the C control block to the D control block that is fixed phase control. The D control block is based on the predetermined output start angle STANG and the predetermined output end angle ENDANG from the recognition of the REF signal in order to improve the connection between the total discharge control of the C control block and the F / B control block. Thus, a solenoid control signal is output so as to start discharging at a predetermined time (for example, for 200 ms) after the engine is completely exploded. Thereafter, when the predetermined time after the complete explosion of the engine elapses, a transition is made to the F / B control block.

14 to 20 are flowcharts of the control of the high-pressure fuel pump 1 by the control unit 515. First, FIG. 14 is a flowchart of each process of FIG.
In step 1401, interrupt processing synchronized with time is performed, for example, every 10 ms. The interrupt process may be synchronized with the rotation at every crank angle of 180 °.

  In step 1402, the state transition determination means 710 performs a state transition determination process of the engine 507 to determine which state to transition from among the A control block to the F / B stop block. In step 1403, the state transition determination The solenoid control signal is calculated by the solenoid control signal calculation means 714 according to the state determined by the determination means 710. In step 1404, the operation delay of the solenoid 200 is corrected by the solenoid operation delay correction means 711. Then, the valve timing correction means 712 corrects the variable valve timing.

  Next, in step 1406, a final angle is calculated based on the obtained reference angle of the solenoid signal. In step 1407, a driving pulse for the solenoid 200 is output by the solenoid driving means 713 based on the final angle.

  15 to 20 are flowcharts of the state transition determination process of the engine 507 in the state transition determination means 710, and FIG. 15 is a flowchart of the state transition determination process in the A control block of the control unit 515.

  Step 1501 is an interrupt process similar to Step 1401. In Step 1502, it is determined whether or not the ignition switch is ON. If it is ON, that is, if YES, the process proceeds to Step 1503, where the crank angle signal It is determined whether CRANK is detected. On the other hand, when the ignition switch is OFF, the routine proceeds to step 1505, where the A control block is held. In the initial state, the solenoid 200 is not energized, and the routine proceeds to step 1506, where this routine is terminated.

  If cranking is started in step 1503 and the first crank angle signal CRANK has been detected, that is, if YES, the routine proceeds to step 1504 and transition is made to the B control block, and the routine proceeds to step 1506 and the routine is terminated. To do. On the other hand, when the first crank angle signal CRANK is not detected, the routine proceeds to step 1505, where the A control block is held.

  FIG. 16 is a flowchart of the state transition determination process in the B control block of the control unit 515.

  Step 1601 is the same interrupt processing as Step 1401. In Step 1602, it is determined whether or not the REF signal is recognized. If it is recognized, that is, if YES, the process proceeds to Step 1607, and the process proceeds to the C control block. Then, the process proceeds to step 1608 to end the present routine. On the other hand, when the REF signal is not recognized, the routine proceeds to step 1603, where it is determined whether or not the ignition switch is ON. When it is ON, that is, when YES, the routine proceeds to step 1604, where the ignition switch is OFF. In some cases, the process proceeds to step 1606, where the A control block is entered, the solenoid 200 is not energized, the process proceeds to step 1608, and this routine is terminated.

  In step 1604, it is determined whether or not a predetermined time MDLTIM (for example, 1 sec) or more has elapsed since the crank angle signal was detected. If the predetermined time MDLTIM or more has elapsed, that is, if YES, the process proceeds to step 1606. Returning to the control block, when the predetermined time MDLTIM or more has not elapsed, the routine proceeds to 1605, where it is held in the B control block, the routine proceeds to step 1608, and this routine is terminated.

  As described above, there is a path from step 1604 to step 1606 in order to prevent the battery from being discharged due to continuous execution of the B control block when the engine stalls in the middle of cranking.

  FIG. 17 is a flowchart of the state transition determination process in the C control block of the control unit 515.

  Step 1701 is an interrupt process similar to step 1401. In step 1702, it is determined whether or not the engine speed is NKTH (for example, 1000 rpm) or more, that is, whether or not a complete explosion has occurred. If yes, that is, if YES, the process proceeds to step 1707, the process proceeds to the D control block, the process proceeds to step 1708, and this routine is terminated. On the other hand, when the engine speed is not equal to or higher than the predetermined speed NKTH, the routine proceeds to step 1703, where it is determined whether or not the ignition switch is ON, and when it is ON, that is, when YES, the routine proceeds to step 1704, where the ignition switch When is OFF, the routine proceeds to step 1706, jumps to the A control block and transitions, the solenoid 200 is not energized, proceeds to step 1608, and this routine is terminated.

  In step 1704, it is determined whether or not the engine speed is equal to or lower than a predetermined speed NENST (for example, 200 rpm). When jumping back to the control block and the engine speed is equal to or greater than the predetermined engine speed NENST, the routine proceeds to 1705, where it is held in the C control block and proceeds to step 1708, and this routine is terminated.

  FIG. 18 is a flowchart of the state transition determination process in the D control block of the control unit 515.

  Step 1801 is an interrupt process similar to Step 1401. In Step 1802, it is determined whether or not the ignition switch is ON. If it is ON, that is, if YES, the process proceeds to Step 1803, and the ignition switch When is OFF, the routine proceeds to step 1809, jumps to the A control block and makes a transition, the solenoid 200 is not energized, proceeds to step 1608, and this routine is terminated.

  In step 1803, it is determined whether or not the engine speed is equal to or lower than a predetermined speed NENST (for example, 200 rpm). If it is equal to or lower than the predetermined speed NENST, that is, YES, it is determined that the engine is stalled. On the other hand, when the engine speed is equal to or higher than the predetermined speed NENST, the routine proceeds to step 1804 to determine whether the engine speed is equal to or lower than the predetermined speed NDOK (for example, 400 rpm). That is, if YES, the routine proceeds to step 1808, where the process proceeds to the C control block, and the routine proceeds to step 1810, where this routine is terminated.

  On the other hand, when the engine speed is greater than or equal to the predetermined engine speed NDOK in step 1804, the process proceeds to step 1805, where it is determined whether or not the D control block continues for a predetermined time FBINT (for example, 300 ms), and continues for a predetermined time FBINT. If YES, that is, if YES, the routine proceeds to step 1807, where the transition is made to the F / B control block, the routine proceeds to step 1810, and this routine is terminated. On the other hand, if it is determined in step 1805 that it has not continued for the predetermined time FBINT or longer, the process proceeds to step 1806 where it is held in the D control block and proceeds to step 1810, and this routine is terminated.

  FIG. 19 is a flowchart of the state transition determination process in the F / B control block of the control unit 515.

  Step 1901 is the same interrupt processing as step 1401. In step 1902, it is determined whether or not the ignition switch is ON. If it is ON, that is, if YES, the process proceeds to step 1903, where the ignition switch When is OFF, the routine proceeds to step 1907 and jumps to the A control block to make a transition. The solenoid 200 is not energized and proceeds to step 1908 to end this routine.

  In step 1903, it is determined whether or not the engine speed is equal to or lower than a predetermined speed NENST (for example, 200 rpm). If the engine speed is equal to or lower than the predetermined speed NENST, that is, YES, it is determined that the engine is stalled. The routine jumps back to step 1 and the energization of the solenoid 200 is not performed. The process proceeds to step 1908, and this routine is terminated. On the other hand, when the engine speed is equal to or higher than the predetermined speed NENST, the routine proceeds to step 1904.

  In step 1904, it is determined whether or not the fuel is being cut. If the fuel is being cut, that is, if YES, the routine proceeds to step 1906, where a transition is made to the F / B stop block. This is for stopping the fuel pumping from the high-pressure fuel pump 1 to prevent the pressure increase of the common rail 53 when the fuel directed from the common rail 53 to each injector 54 is zero, and then proceeding to step 1908 and proceeding to the main step. End the routine. On the other hand, when the fuel cut is not in progress, the routine proceeds to step 1905, where it is held in the F / B control block, proceeds to step 1908, and this routine is terminated.

  FIG. 20 is a flowchart of the state transition determination process in the F / B stop block of the control unit 515.

  Step 2001 is an interrupt process similar to Step 1401. In Step 2002, it is determined whether or not the ignition switch is ON. If it is ON, that is, if YES, the process proceeds to Step 2003, and the ignition switch When is OFF, the routine proceeds to step 2007 and jumps to the A control block to make a transition. The solenoid 200 is not energized and proceeds to step 2008 to end this routine.

  In step 2003, it is determined whether or not the engine speed is equal to or lower than a predetermined speed NENST (for example, 200 rpm). If it is equal to or lower than the predetermined speed NENST, that is, if YES, it is determined that the engine is stalled. The process jumps back to step S3, the energization of the solenoid 200 is not performed, the process proceeds to step 2008, and this routine is finished. On the other hand, when the engine speed is equal to or higher than the predetermined speed NENST, the routine proceeds to step 2004.

In step 2004, it is determined whether or not the fuel is being cut. If the fuel is being cut, that is, if YES, the routine proceeds to step 2005 and is held in the F / B stop block, and the solenoid 200 is not energized. Proceeding to 2008, this routine ends. On the other hand, when the fuel cut is not in progress, the routine proceeds to step 2006, where the process proceeds to the F / B control block, proceeds to step 2008, and this routine ends.
As described above, the embodiment of the present invention exhibits the following functions by the above configuration.

  The control unit 515 of the embodiment includes an injector 54 provided in a cylinder 507b, a high-pressure fuel pump 1 that pumps fuel to the injector 54, and a crank angle sensor 516 that detects the position of the crankshaft 507d. The high-pressure fuel pump 1 controls the fuel pressure in the pump chamber 8 based on the solenoid signal, the pump drive cam 100 that drives the plunger 2, and the position of the pump drive cam 100. The control unit 515 includes a basic angle calculation means 701 for calculating a basic angle of the solenoid signal based on detection signals from the crank angle sensor 516 and the fuel pressure sensor 56; Target fuel pressure calculating means 702 for calculating the target fuel pressure, and actual fuel Is provided with a fuel pressure input processing means 703, and a solenoid control signal calculating means 714 for calculating a reference angle of the solenoid signal based on each means, and a state in which the state of the control unit 515 is determined and shifted Transition determination means 710 and solenoid drive means 713 for driving the solenoid 200 of the high-pressure fuel pump 1 are provided. The solenoid control signal calculation means 714 detects the crank angle sensor 516 from the signal detection timing of the crank angle sensor 516. And the cam angle sensor 511 until the phase of the cam angle sensor 511 is finalized, an equidistant energization control block 705 for supplying a driving signal to the high-pressure fuel pump 1 at least twice, and feedback control after the control unit 515 is completely exploded Block 708 and the like, and the state transition Since the transition of each of the six control blocks is performed by the determination unit 710, even if it is not possible to recognize where the position of the plunger 2 is, the common rail is within one reciprocation stroke of the plunger 2 from the start of the engine 507. 53 can reliably discharge the fuel.

  FIG. 21 is an operation timing chart when the engine is started by the high-pressure pump 1 in the control unit 515. When cranking is started from the engine start and the first crank angle signal is determined, the control unit 515 transits to the B control block. The energization control is performed at equal intervals, and the ON-OFF control signal for the solenoid 200 is repeated. Here, for each ON signal, the suction valve engaging member 201 operates in a direction to close the suction valve 5, and the plunger 2 has shifted from the stop position 21a to the compression stroke through the bottom dead center. Even when it is not possible to determine when the point is reached, any one of the ON signals in the vicinity of the bottom dead center of the plunger 2 serves as a trigger, and the fuel discharge to the common rail 53 by the high-pressure fuel pump 1 is started. Thus, the fuel can be pumped as early as one cycle, and the engine start time can be prevented from being prolonged.

  After the plunger phase is determined, a solenoid control signal is output by angle or time control based on the REF signal, and the fuel pressure 21b at the time of fuel injection by each injector 54 becomes the fuel pressure 22b at the time of conventional fuel injection (FIG. 22). The fuel pressure can be increased, the fuel pressure can be increased, atomization of the spray particle diameter from each injector 54 can be promoted, and the HC emission amount can be reduced.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various changes in design can be made without departing from the spirit of the present invention described in the claims. It can be done.

  For example, in the embodiment, the high-pressure fuel pump 1 is disposed on the cam shaft of the exhaust valve 526, but is disposed on the cam shaft of the intake valve 514 or synchronized with the crank shaft 507d of the cylinder 507b. In this case as well, the detection signal switching means 715 and the other drive signal setting means 717 can be applied to signal disconnection and the like, and the timing is adjusted by the valve timing drive means. be able to.

  In addition, the B drive solenoid drive signal is controlled at equal intervals by repeatedly outputting a drive signal having a predetermined width at a predetermined period when the engine is started. Even when the signals from the crank angle signal 516 and the cam angle signal 511 are not detected at all due to the disconnection of the signal or the like, the equal interval energization control can be applied. Thus, the fuel can be supplied to the injector 54 and the vehicle can be moved to a safe point to ensure the safety of the driver. Furthermore, although it is synchronized with the rise of the signal of the crank angle sensor 516, it may be synchronized with the fall of the signal of the crank angle sensor 516, or may be synchronized with the rise and fall. Regarding the detection of the signal of the crank angle sensor 516 by the tooth missing portion, a signal having other characteristics may be detected.

1 is an overall configuration diagram of an engine including a high-pressure fuel pump control device and an in-cylinder injection engine control device according to the present embodiment. FIG. 2 is an internal configuration diagram of the high-pressure fuel pump control device and the in-cylinder injection engine control device of FIG. The whole block diagram of the fuel system provided with the high-pressure fuel pump of FIG. FIG. 4 is a longitudinal sectional view of the high pressure fuel pump of FIG. 3. The operation | movement timing chart of the high pressure fuel pump of FIG. FIG. 6 is a supplementary explanatory diagram of the operation timing chart of FIG. 5. FIG. 2 is a control block diagram of a high pressure fuel pump by the high pressure fuel pump control device and the in-cylinder injection engine control device of FIG. 1. The state transition diagram of FIG. The operation | movement timing chart of the high pressure fuel pump control apparatus of FIG. 1 and a cylinder injection engine control apparatus. The operation | movement timing chart of the high pressure fuel pump control apparatus of FIG. 1 and a cylinder injection engine control apparatus. 2 is an operation timing chart from an A control block to a B control block in the high pressure fuel pump control device and the in-cylinder injection engine control device of FIG. 1. 2 is an operation timing chart from a B control block to a C control block in the high pressure fuel pump control device and the in-cylinder injection engine control device of FIG. 1. 2 is an operation timing chart from a C control block to a D control block in the high pressure fuel pump control device and the in-cylinder injection engine control device of FIG. 1. The operation | movement flowchart of the high-pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement flowchart of the state transition determination process in the A control block of the high pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement flowchart of the state transition determination process in the B control block of the high-pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement flowchart of the state transition determination process in the C control block of the high-pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement flowchart of the state transition determination process in D control block of the high-pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement flowchart of the state transition determination process in the F / B control block of the high pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement flowchart of the state transition determination process in the F / B stop block of the high pressure fuel pump control apparatus and in-cylinder injection engine control apparatus of FIG. The operation | movement timing chart at the time of the engine start in the high pressure fuel pump control apparatus and cylinder injection engine control apparatus of FIG. The operation | movement timing chart at the time of engine starting in the conventional high-pressure fuel pump control apparatus and in-cylinder injection engine control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High pressure fuel pump 2 Plunger 5 Suction valve 5a Valve closing spring 7 Cylinder chamber 8 Pump chamber 9 Solenoid chamber 54 Fuel injection valve (injector)
56 Fuel pressure sensor 100 Pump drive cam 200 Solenoid 201 Suction valve engaging member 202 Valve opening spring 507 In-cylinder injection engine 507b Cylinder 507d Crankshaft 511 Cam angle sensor 514 Intake valve 515 High-pressure fuel pump control device and in-cylinder injection engine control device ( control unit)
516 Crank angle sensor 526 Exhaust valve 701 Basic angle calculation means 702 Target fuel pressure calculation means 703 Fuel pressure input processing means 705 Equal interval energization control block 708 Feedback control block 710 State transition determination means 711 Solenoid operation delay correction means 712 Valve timing correction means 713 Solenoid Drive means 714 Solenoid control signal calculation means 715 Detection signal switching means 716 Drive signal setting means 717 Other drive signal setting means

Claims (2)

A fuel injection valve provided in the cylinder, the fuel pressure fuel pump for a fuel to be pumped to the injection valve, a crank angle sensor and the in-cylinder that controls the in-cylinder injection engine having for detecting the position of the crankshaft of the cylinder In the injection engine control device,
The high-pressure fuel pump includes a plunger that pressurizes fuel in the high-pressure fuel pump by a solenoid that is driven based on a solenoid signal ; a pump drive cam that drives the plunger and opens and closes the intake valve or the exhaust valve of the cylinder ; , and a cam angle sensor for detecting the position of the pump drive cam,
The in-cylinder injection engine control device includes a basic angle calculation means for calculating a basic angle of the solenoid signal based on detection signals from the crank angle sensor and a fuel pressure sensor provided in the fuel injection valve, and a target fuel pressure. The target fuel pressure calculating means for calculating the fuel pressure, the fuel pressure input processing means for outputting the actual fuel pressure, and a plurality of different control blocks for controlling the solenoid, each control block is based on each of the means from the basic angle. Solenoid control signal computing means for computing a reference angle of the solenoid signal, state transition judging means for judging the state of the in-cylinder injection engine and making a transition of the control block from the judgment result, and the transitioned control a solenoid driving means for driving the solenoid based on the solenoid signal of the block, actuation delay of the solenoid Solenoid operation delay correcting means for correcting, valve timing driving means for adjusting opening / closing timing of the intake valve or exhaust valve of the cylinder, and correction of the opening / closing timing based on the advance angle of the driving cam by the bubble timing driving means And valve timing correction means for
The in-cylinder injection engine control device corrects the reference angle of the solenoid signal by the solenoid control signal calculating means by the operation delay amount of the solenoid and the cam advance angle, and the corrected reference angle of the solenoid signal is obtained. An in-cylinder injection engine control device that outputs the final angle to the solenoid driving means . The control block is used for energizing the solenoid at equal intervals by the solenoid signal from the signal detection time of the crank angle sensor to the time when the phase of the crank angle sensor and the cam angle sensor is determined. The in-cylinder injection engine according to claim 1, further comprising: an interval energization control block; and a feedback control block after the complete explosion of the in-cylinder injection engine so that the actual fuel pressure becomes the target fuel pressure. Control device.

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