JP2017106413A - Pump control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology which extremely accurately detects the displacement of a mounting angle irrespective of a magnitude of the mounting angle of a fuel supply pump, in a fuel supply system which controls a pressure-sending period in which fuel is pressure-sent from the fuel supply pump in a pressure-sending stroke by a metering valve.SOLUTION: In a pump control device which meters a pressure-sending period in a pressure-sending stroke of a fuel supply pump by controlling a metering valve, in S402, a pressure acquisition part acquires fuel pressure from a pressure sensor which is installed at a fuel suction side of the fuel supply pump. In S404, an angle detection part detects at least one actual angle of either of a top dead point and a bottom dead point of a plunger on the basis of pressure pulsation at a fuel suction side which is generated by the reciprocation of the plunger. In S408, a control part corrects energization control to the metering valve on the basis of a difference between the actual angle which is detected by the angle detection part and at least one target angle of either of a top dead point and a bottom dead point corresponding to the actual angle.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to a pump control device that is applied to a fuel supply system that controls a pumping period by controlling a pumping period during which fuel is pumped from a fuel supply pump by a metering valve in a pumping stroke.

  When adjusting the pumping amount of the fuel supply pump that pressurizes the fuel stored in the fuel tank and pumps it to the common rail, the fuel supply is controlled by the metering valve during the pumping stroke. A configuration for metering the pumping amount of the pump is known.

  For example, in the technique described in Patent Document 1, the control command value for the metering valve is set based on the feedback amount with the common rail pressure as the target pressure. The integral term of the feedback amount is separated into an angular error caused by a deviation in the mounting angle of the fuel supply pump and a time error that is a deviation in response time when the metering valve opens and closes. Based on the above, the control command value for the metering valve is corrected.

JP2013-113135A

  The integral term of the feedback amount in Patent Document 1 includes a performance change such as a change in the pumping amount of the fuel supply pump, an injection amount error of the fuel injection valve, and the like. Therefore, it is difficult to obtain the deviation of the mounting angle of the fuel supply pump with high accuracy from the angle error of the integral term of the feedback amount.

  Furthermore, when the angle error caused by the deviation of the mounting angle of the fuel supply pump is larger than the range in which the control command value can be corrected by feedback control, the deviation of the mounting angle of the fuel supply pump cannot be obtained from the angle error of the integral term. .

  One aspect of the present disclosure provides a fuel supply system that controls a pumping period in which fuel is pumped from a fuel supply pump in a pumping stroke by using a metering valve, regardless of the mounting angle deviation of the fuel supply pump. An object is to provide a technique for detecting a displacement as accurately as possible.

  According to one aspect of the present disclosure, the pumping amount of the fuel supply pump (20) that pumps the fuel sucked into the pressurizing chamber (100) to the engine by the reciprocating movement of the plunger (26) driven by the rotation of the cam (24). A pump control device (70) applied to a fuel supply system for controlling and metering a pumping period in which fuel is pumped from a fuel supply pump in a pumping stroke by controlling energization to a metering valve (30) The pressure acquisition unit (72, S402), the angle detection unit (74, S400, S404, S410 to S432), and the control unit (76, S408) are provided.

  The pressure acquisition unit acquires the fuel pressure in the fuel passage from a pressure sensor installed in the fuel passage on the fuel intake side of the fuel supply pump. The angle detection unit detects the actual angle of at least one of the top dead center and the bottom dead center based on the pressure pulsation generated in the fuel pressure acquired by the pressure acquisition unit as the plunger reciprocates. To do.

The control unit corrects the energization control for the metering valve based on the difference between the actual angle detected by the angle detection unit and the target angle of at least one of the top dead center and the bottom dead center corresponding to the actual angle. To do.
Pressure pulsation generated on the fuel suction side of the fuel supply pump due to the reciprocating movement of the plunger occurs when the direction of movement of the plunger changes. That is, when the plunger descends and reaches the bottom dead center and rises toward the top dead center, and when the plunger rises and reaches the top dead center and descends toward the bottom dead center.

  Therefore, the actual angle of at least one of the top dead center and the bottom dead center of the plunger can be detected based on the timing at which pressure pulsation occurs on the fuel suction side of the fuel supply pump. The magnitude of the deviation of the actual mounting angle with respect to the target mounting angle, which is the deviation of the mounting angle of the fuel supply pump, corresponds to the actual angle of at least one of the top dead center and the bottom dead center of the plunger. It can be calculated as the difference between the target angle of at least one of the dead center and the top dead center.

  The actual angle of at least one of the top dead center and the bottom dead center of the plunger is the pressure pulsation generated on the fuel suction side of the fuel supply pump regardless of the magnitude of the deviation of the mounting angle of the fuel supply pump. It can be detected by the timing of occurrence.

Further, the pressure pulsation generated by the reciprocating movement of the plunger does not occur due to a factor other than the change of the moving direction of the plunger.
Therefore, regardless of the magnitude of the deviation in the mounting angle of the fuel supply pump, it is possible to detect the deviation in the mounting angle of the fuel supply pump as accurately as possible based on the pressure pulsation generated on the fuel suction side of the fuel supply pump. it can.

  Note that the reference numerals in parentheses described in this column and in the claims indicate the correspondence with the specific means described in the embodiment described later as one aspect, and the technical scope of the present invention. It is not limited.

The block diagram which shows the fuel supply system by this embodiment. The time chart which shows the relationship between the lift position of a plunger, and pressure pulsation. The flowchart which shows the main process of a pump control process. The flowchart which shows the detection process of the mounting angle of a fuel supply pump.

Embodiments to which the present invention is applied will be described below with reference to the drawings.
[1. Constitution]
A fuel supply system 10 shown in FIG. 1 is, for example, for injecting and supplying fuel to a diesel engine 2 for an automobile. Hereinafter, the diesel engine is also simply referred to as an engine. The fuel supply system 10 includes a fuel tank 12, a feed pump 14, a fuel filter 16, a fuel supply pump 20, a common rail 40, a fuel injection valve 50, and an ECU 70. ECU is an abbreviation for Electronic Control Unit.

  The electric feed pump 14 sucks up the fuel in the fuel tank 12 and supplies it to the fuel supply pump 20. The fuel filter 16 is installed in a fuel supply passage 200 that is a fuel passage on the suction side of the fuel supply pump 20, and removes foreign matters from the fuel supplied from the feed pump 14 through the fuel supply passage 200 to the fuel supply pump 20. .

  The pressure sensor 18 is installed in the fuel supply passage 200 between the fuel filter 16 on the fuel intake side of the fuel supply pump 20 and the fuel supply pump 20, and the fuel pressure in the fuel supply passage 200 on the intake side of the fuel supply pump 20. Is detected. Hereinafter, the fuel pressure on the suction side of the fuel supply pump 20 detected by the pressure sensor 18 is also referred to as a feed pressure.

  The fuel supply pump 20 pressurizes and feeds fuel sucked from the feed pump 14 into the pressurizing chamber 100 by reciprocating the plunger 26 as the cam 24 of the cam shaft 22 driven by the crankshaft rotates.

  A metering valve 30 is installed in the fuel supply passage 200 on the suction side of the fuel supply pump 20. The closing timing of the metering valve 30 is energized and controlled by the ECU 70. The metering valve 30 is a so-called normally open solenoid valve that opens without being energized. The metering valve 30 is energized and closed at a predetermined timing in the pressure feed stroke.

  A check valve 32 that allows only fuel to flow out from the pressurizing chamber 100 and restricts fuel from flowing into the pressurizing chamber 100 from the common rail 40 on the high pressure side is provided on the pressure feeding side of the fuel supply pump 20. Is provided.

  In the intake stroke, since the energization to the metering valve 30 is cut off, the metering valve 30 is in the open state. When the metering valve 30 is opened, when the plunger 26 moves from the top dead center where it rises most to the bottom dead center where it falls most, the volume of the pressurizing chamber 100 increases and the pressure in the pressurizing chamber 100 decreases. As a result, the fuel supplied from the feed pump 14 is sucked into the pressurizing chamber 100.

  Thereafter, when the plunger 26 keeps the valve opening state without energizing the metering valve 30 in the pressure-feeding stroke from the bottom dead center to the top dead center, the fuel sucked into the pressurizing chamber 100 is increased as the plunger 26 rises. Then, the fuel is discharged from the metering valve 30 through the fuel discharge passage 210 to the fuel tank 12 side.

  When the metering valve 30 is energized in the middle of the pumping stroke and the metering valve 30 is closed at a predetermined angular timing, pressurization of the fuel in the pressurizing chamber 100 is started. When the pressure in the pressurizing chamber 100 exceeds the common rail pressure, the fuel in the pressurizing chamber 100 is pumped to the common rail 40 via the check valve 32.

  By controlling the energization start timing of the metering valve 30, the pumping period in which the fuel in the pressurizing chamber 100 is pressurized and pumped from the fuel supply pump 20 to the common rail 40 in the pumping stroke is controlled. Therefore, by controlling the energization start timing of the metering valve 30, the pumping amount of the fuel supply pump 20 can be metered. If the metering valve 30 is closed early, the pumping amount increases, and if the metering valve 30 is closed late, the pumping amount decreases.

  When the metering valve 30 is energized and closed, and the pressure in the pressurizing chamber 100 rises due to the rise of the plunger 26, the fuel pressure in the pressurizing chamber 100 regulates even if the metering valve 30 is cut off. Since the quantity valve 30 is kept closed, the fuel in the pressurizing chamber 100 is pressurized. Therefore, it is not necessary to continue energizing the metering valve 30 until the plunger 26 reaches the top dead center.

  The common rail 40 is a hollow member that accumulates fuel pumped from the fuel supply pump 20. The common rail 40 is provided with a pressure sensor 42 for detecting the common rail pressure, and a pressure reducing valve 44 for opening the valve to discharge the fuel in the common rail 40 to the fuel tank 12 side to reduce the common rail pressure.

  The fuel injection valve 50 is installed in each cylinder of the engine 2 and injects fuel accumulated in the common rail 40 into the cylinder. The fuel injection valve 50 has a known configuration in which, for example, the lift of the nozzle needle that opens and closes the nozzle hole is controlled by the pressure in the control chamber. The injection amount of the fuel injection valve 50 is controlled by the pulse width of the injection command signal commanded from the ECU 70. As the pulse width of the injection command signal increases, the injection amount increases.

  The ECU 70 is mainly configured of a microcomputer including a CPU and a semiconductor memory such as a RAM, a ROM, and a flash memory. Each function of the ECU 70 is realized by the CPU executing a program stored in a non-transitional tangible recording medium such as a ROM or a flash memory. The number of microcomputers constituting the ECU 70 may be one or more.

  ECU70 is provided with the pressure acquisition part 72, the angle detection part 74, and the control part 76 as a structure of the function implement | achieved when CPU runs a program. The technique for realizing these elements constituting the ECU 70 is not limited to software, and hardware in which some or all of the elements are combined with a logic circuit, an analog circuit, or the like may be used.

  The ECU 70 executes various controls of the fuel supply system 10 based on detection signals acquired from the pressure sensors 18 and 42, the crank angle sensor 60, the water temperature sensor 62, various sensors including an accelerator opening sensor (not shown), and the like. The crank angle sensor 60 detects a crank angle indicating an engine rotation angle. The water temperature sensor 62 detects the water temperature of the engine 2.

  For example, the ECU 70 controls the pumping amount of the fuel supply pump 20 so that the common rail pressure detected by the pressure sensor 42 becomes the target pressure. The pumping amount of the fuel supply pump 20 is determined by the valve closing start timing of the metering valve 30 that defines the pumping period of the fuel supply pump 20.

  The ECU 70 measures and sets in advance a characteristic map representing the correlation between the crank angle representing the valve closing start timing of the metering valve 30 and the pumping amount of the fuel supply pump 20. The ECU 70 sets the energization start timing of the metering valve 30 based on the valve closing start timing acquired from this characteristic map, and regulates the pumping amount of the fuel supply pump 20.

  In addition, the ECU 70 stores a so-called TQ map indicating the correlation between the pulse width (T) of the injection command signal for instructing the fuel injection valve 50 to inject fuel and the injection amount (Q) for each predetermined pressure range of the common rail pressure. Stored in flash memory.

  When the injection amount of the fuel injection valve 50 is determined based on the engine speed and the accelerator opening, the ECU 70 is determined by referring to the TQ map of the corresponding pressure range according to the common rail pressure detected by the pressure sensor 42. The pulse width of the injection command signal to the fuel injection valve 50 corresponding to the injected amount is acquired from the TQ map.

  As described above, the pumping amount of the fuel supply pump 20 is determined at the timing of starting energization of the metering valve 30 in the pumping stroke. The timing for starting energization of the metering valve 30 is defined by the crank angle. Then, the pumping amount pumped by the fuel supply pump 20 in the pumping stroke is determined by the pumping period from the start of energization to the metering valve 30 until the plunger 26 reaches top dead center.

  However, if there is a deviation in the actual mounting angle with respect to the target mounting angle of the fuel supply pump 20, even if energization of the metering valve 30 is started at the crank angle that is the target pumping amount, The pumping period to the top dead center is shifted. As a result, the actual pumping amount deviates from the target pumping amount.

  Here, the magnitude of the deviation of the mounting angle of the fuel supply pump 20 is such that the actual angle of at least one of the top dead center and the bottom dead center of the plunger 26, and the top dead center and the top dead center corresponding to the actual angle. Can be detected as a difference from the target angle of at least one of the above.

Therefore, in the present embodiment, the deviation of the mounting angle of the fuel supply pump 20 is detected by detecting the actual angle of at least one of the top dead center and the bottom dead center of the plunger 26.
As shown in FIG. 2, when the movement direction changes toward the bottom dead center after the plunger 26 reaches the top dead center, the pressure in the pressurizing chamber 100 rapidly decreases, and thus pressure pulsation occurs in the pressurizing chamber 100. To do. Then, this pressure pulsation propagates to the fuel supply passage 200 on the fuel intake side of the fuel supply pump 20 and a pressure pulsation is generated in the feed pressure.

  Similarly, when the moving direction changes toward the top dead center after the plunger 26 reaches the bottom dead center, the pressure in the pressurizing chamber 100 increases, and thus pressure pulsation occurs in the pressurizing chamber 100. Then, this pressure pulsation propagates to the fuel supply passage 200 on the fuel intake side of the fuel supply pump 20 and a pressure pulsation is generated in the feed pressure.

  The pressure pulsation generated on the fuel suction side of the fuel supply pump 20 is detected by the pressure sensor 18. If the start timing at which pressure pulsation occurs can be detected, the actual angles of the top dead center and the bottom dead center can be detected. Hereinafter, the pressure pulsation generated when the moving direction of the plunger 26 changes is also referred to as a plunger pulsation.

  However, a propagation delay corresponding to the length of the fuel supply passage 200 between the fuel supply pump 20 and the pressure sensor 18 occurs before the plunger pulsation reaches the pressure sensor 18. As the length of the fuel supply passage 200 between the fuel supply pump 20 and the pressure sensor 18 increases, the propagation delay increases. Propagation delay also varies depending on fuel properties. The fuel property represents the type of fuel such as gasoline and light oil, and the fuel temperature on the fuel suction side of the fuel supply pump 20.

The type of fuel is preset according to the fuel to be used. The fuel temperature on the fuel intake side is estimated from the water temperature sensor 62.
When the direction of movement of the plunger 26 that has reached the top dead center changes toward the bottom dead center, the metering valve 30 is closed. The metering valve 30 opens when the plunger 26 starts to descend from the top dead center toward the bottom dead center and the pressure in the pressurizing chamber 100 decreases. There is a time delay before the plunger 26 starts to open from the closed state.

  Therefore, in order to detect the top dead center angle from the plunger pulsation, in addition to the propagation delay corresponding to the length of the fuel supply passage 200 between the fuel supply pump 20 and the pressure sensor 18 and the fuel properties, the plunger 26 It is desirable to consider the time delay from when the valve is closed to when the valve starts to open.

[2. processing]
A pump control process for the fuel supply pump 20 executed by the ECU 70 will be described based on the flowcharts of FIGS. 3 and 4. In the flowcharts of FIGS. 3 and 4, “S” represents a step.

(1) Main Process The main process of FIG. 3 is always executed until the determination in S406 becomes Yes during one trip from when the engine 2 starts to stop.

  In S400 of FIG. 3, the pressure acquisition unit 72 determines whether a detection condition for detecting the mounting angle of the fuel supply pump 20 is satisfied. The detection condition is that the engine speed is equal to or lower than a predetermined speed at which the next plunger pulsation does not occur before the plunger pulsation disappears. The predetermined number of revolutions is set by measuring in advance. The idling engine speed satisfies that the engine engine speed is not more than a predetermined engine speed.

  When the determination in S400 is Yes and the detection condition is satisfied, in S402, the pressure acquisition unit 72 acquires the feed pressure from the pressure sensor 18 for a predetermined detection period in order to detect the start timing of the plunger pulsation. The pressure acquisition unit 72 acquires the feed pressure from the pressure sensor 18 at a sampling rate at which a change in plunger pulsation can be detected.

  Since the plunger pulsation occurs when the moving direction of the plunger 26 changes between the top dead center and the bottom dead center, the detection period is set to 180 ° CA, for example. Further, the start angle of the detection period is set to a predetermined angle before the normal top dead center or bottom dead center angle in consideration of an error in the mounting angle of the fuel supply pump 20.

  In the angle detection process of S404, the angle detection unit 74 detects the mounting angle of the fuel supply pump 20 based on the plunger pulsation acquired by the pressure acquisition unit 72. Details of the processing of S404 will be described later.

  In S406, the angle detection unit 74 determines whether or not the detection flag is on. When the engine is started, the detection flag is set to the initial value OFF. The detection flag is set to ON when the mounting angle of the fuel supply pump 20 can be detected in the angle detection process of S404. The detection flag remains off when the mounting angle of the fuel supply pump 20 cannot be detected in the angle detection process of S404.

  If the determination in S406 is Yes and the detection flag is on, in S408, the control unit 76 corrects the energization start timing for the metering valve 30 based on the mounting angle shift of the fuel supply pump 20.

  The control unit 76 detects the actual angle of at least one of the top dead center and the bottom dead center of the plunger 26 detected by the angle detection unit 74 in the angle detection process of S404, and the top dead center and top dead center corresponding to the real angle. The deviation of the mounting angle is calculated as the difference from the target angle of at least one of the points.

(2) Angle Detection Processing In S410 of FIG. 4, the angle detection unit 74 differentiates the feed pressure of the detection period acquired by the pressure acquisition unit 72 for each time interval in which a change in plunger pulsation can be detected. If the differential value is positive, the feed pressure increases, and if the differential value is negative, the feed pressure decreases.

  In S412, the angle detection unit 74 shifts the differential value of the feed pressure one by one from the start timing of the detection period one by one until the later-described S430 is executed or the determination in S432 becomes Yes. Are sequentially integrated every predetermined period. The predetermined period is set by measuring in advance a period during which at least one of the rise start timing and the fall start timing of the plunger pulsation can be detected based on the integrated value of the differential values.

  In S414, the angle detection unit 74 determines whether or not the integrated value integrated in S412 is greater than or equal to a positive determination value for detecting the bottom dead center. If the determination in S414 is No, the process proceeds to S422.

  The pressure pulsation generated when the plunger 26 starts to rise after reaching the bottom dead center first rises as shown in FIG. Therefore, if the determination in S414 is Yes and the integrated value is greater than or equal to the positive bottom dead center determination value, it can be determined that the pressure pulsation is generated when the plunger 26 starts to rise after reaching the bottom dead center. .

  In S416, the angle detection unit 74 acquires the start timing of the predetermined period in which the current integrated value is calculated as the start timing of the plunger pulsation. This start timing is a time timing. In step S418, the angle detection unit 74 determines whether or not the acquired start timing is within the mask period.

  The mask period is a period from the start of energization to the metering valve 30 until the pulsation width of the pressure pulsation generated by closing the metering valve 30 becomes equal to or less than a predetermined value. Hereinafter, the pressure pulsation generated when the metering valve 30 is closed is also referred to as a metering valve pulsation.

  The mask period is set to a value that does not cause an erroneous determination in the determinations of S414 and S422 for detecting the start timing of the plunger pulsation due to the metering valve pulsation overlapping the plunger pulsation. For example, the mask period is a period from when the valve start command is sent to the metering valve 30 when the metering valve 30 is energized until the metering valve pulsation disappears and the amplitude of the metering valve pulsation becomes zero. is there.

  When the metering valve pulsation exceeds the top dead center, the plunger 26 may overlap with the plunger pulsation that occurs when the plunger 26 reaches the top dead center and descends, so as in the mask period 3 shown in FIG. The mask period may reach the next intake stroke after the pumping stroke.

Note that a period including a period in which it is estimated that plunger pulsation is generated from the start of energization to the metering valve 30 according to the energization start timing to the metering valve 30 may be set as a mask period.
When the determination in S418 is Yes and the start timing of the plunger pulsation is within the mask period as in the mask period 2 of FIG. 2, the process proceeds to S432.

  When the determination in S418 is No and the start timing of the plunger pulsation is out of the mask period as in the mask period 1 of FIG. 2, in S420, the angle detection unit 74 sets the start timing of the plunger pulsation to the propagation of the plunger pulsation. Correct based on the delay time and find the actual angle of the bottom dead center.

  Specifically, the angle detector 74 converts the propagation delay time of the plunger pulsation into a crank angle based on the engine speed. Then, the actual angle of the bottom dead center is obtained by correcting the start angle corresponding to the start timing of the plunger pulsation, which is the time timing, with a value obtained by converting the propagation delay time into the crank angle. Conversion from the propagation delay time to the angle is executed by the following equation (1).

Angle = time x (engine speed / 60) x 360
= Time x engine speed x 6 (1)
After execution of S420, the process proceeds to S430.

  In S422, the angle detection unit 74 determines whether or not the integrated value integrated in S412 is equal to or less than a negative determination value for detecting the top dead center. If the determination in S422 is No, the process proceeds to S432.

  The pressure pulsation generated when the plunger 26 starts descending after reaching the top dead center first descends as shown in FIG. Therefore, if the determination in S422 is Yes and the integrated value is equal to or less than the negative top dead center determination value, it can be determined that the pressure pulsation is generated when the plunger 26 starts to descend after reaching the top dead center. .

  In S424, the angle detection unit 74 acquires the start timing of the predetermined period for which the current integrated value is calculated as the start timing of the plunger pulsation. This start timing is a time timing. In step S426, the angle detection unit 74 determines whether or not the acquired start timing is within the mask period described above.

If the determination in S426 is Yes and the start timing of the plunger pulsation is within the mask period as in the mask period 3 of FIG. 2, the process proceeds to S432.
If the determination in S426 is No and the start timing is out of the mask period as in the next plunger pulsation of the mask period 1 in FIG. 2, the angle detection unit 74 in S428 determines the propagation delay time and metering of the plunger pulsation. Based on the valve opening delay time of the valve 30, the start timing of the plunger pulsation is corrected to obtain the actual angle of the top dead center.

  Specifically, the angle detector 74 converts the propagation delay time of the plunger pulsation and the valve opening delay time of the metering valve 30 into a crank angle based on the engine speed. Then, by correcting the start angle corresponding to the start timing of the plunger pulsation, which is the time timing, with a value obtained by converting the propagation delay time and the valve opening delay time of the metering valve 30 into a crank angle, the actual top dead center is obtained. Find the angle.

After execution of S428, the process proceeds to S430.
In S430, the angle detection unit 74 sets the detection flag to ON.
If the determinations in S414 and S422 are No, or the determination in S418 or S426 is Yes, in S432, the angle detection unit 74 determines whether or not the integrated value has been determined over the entire 180 ° CA detection period. To do.

  If the determination in S432 is No and a portion for which the integrated value has not yet been determined remains in the detection period, the process proceeds to S412. If the determination in S432 is Yes and the integrated value is determined over the entire detection period, this process ends. In this case, the detection flag remains off.

  In the above embodiment, the ECU 70 corresponds to an example of a pump control device. In the above embodiment, S402 corresponds to an example of processing as the pressure acquisition unit 72, S400, S404, and S410 to S432 correspond to an example of processing as the angle detection unit 74, and S408 serves as the control unit 76. This corresponds to an example of processing.

[3. effect]
In the embodiment described above, the following effects (1) to (4) can be obtained.
(1) The actual mounting angle of the fuel supply pump 20 is detected based on the start timing of the plunger pulsation generated when the moving direction of the plunger 26 changes between the top dead center and the bottom dead center. Thereby, regardless of the magnitude of the deviation between the target mounting angle and the detected actual mounting angle, the mounting angle deviation can be detected.

  (2) Plunger pulsation occurs when the moving direction of the plunger 26 changes between top dead center and bottom dead center, and does not occur due to other factors. Therefore, the actual mounting angle of the fuel supply pump 20 can be detected with high accuracy based on the start timing of the plunger pulsation.

  (3) Since the differential value of the feed pressure is shifted one by one from the start timing of the feed pressure detection period, the pulsation start timing is determined based on the integrated value obtained by integrating the differential value of the feed pressure every predetermined period. The noise contained in the feed pressure detected by can be canceled.

(4) Since the generation period of the metering valve pulsation generated by closing the metering valve 30 is masked as a mask period and the start timing of the plunger pulsation is detected, erroneous determination of the start timing of the plunger pulsation can be suppressed as much as possible.
[4. Other Embodiments]
(1) As a detection condition of S400 in FIG. 3, in addition to the engine speed being equal to or lower than the predetermined speed, it may be added that the energization control to the metering valve 30 is stopped. Further, as the detection condition of S400 in FIG. 3, it may be adopted that the energization control to the metering valve 30 is stopped instead of the engine speed being equal to or lower than the predetermined speed.

  By making it the detection condition that the energization control to the metering valve 30 is stopped, it is possible to prevent the metering valve pulsation from overlapping the plunger pulsation. The energization control to the metering valve 30 is stopped when the pressure reducing valve 44 is opened to reduce the common rail pressure.

  (2) In the above embodiment, the differential value obtained by differentiating the feed pressure is integrated to detect the start timing of the plunger pulsation. On the other hand, even if the movement direction of the plunger 26 changes between the top dead center and the bottom dead center, it is determined that the differential value of the feed pressure is out of the predetermined range, and the start timing of the plunger pulsation is detected. Good.

  (3) The start timing of the plunger pulsation may be detected by determining that the feed pressure changes from the target pressure when the plunger pulsation does not occur in an increasing direction or a decreasing direction exceeding a predetermined range.

  (4) When the pressure acquisition unit 72 acquires the feed pressure from the pressure sensor 18, noise may be removed by performing filter processing with a low-pass filter, a high-pass filter, or a band-pass filter. In this case, it is desirable to detect the mounting angle of the fuel supply pump 20 by correcting the start timing of the plunger pulsation based on the phase delay due to the filter processing.

  (5) In the above embodiment, the actual mounting angle of the fuel supply pump 20 based on the start timing of the plunger pulsation that occurs when the movement direction of the plunger 26 changes at one of top dead center or bottom dead center in one trip. Is detected, the main process of FIG. 1 is terminated.

  In contrast, in one trip, the actual mounting angle of the fuel supply pump 20 is determined based on the start timing of the plunger pulsation that occurs when the moving direction of the plunger 26 changes at both the top dead center and the bottom dead center. It may be detected. When the actual mounting angle of the fuel supply pump 20 is detected in one trip, the main process in FIG. 1 ends.

  (6) A plurality of functions of one constituent element in the above embodiment may be realized by a plurality of constituent elements, or a single function of one constituent element may be realized by a plurality of constituent elements. Further, a plurality of functions possessed by a plurality of constituent elements may be realized by one constituent element, or a single function possessed by a plurality of constituent elements may be realized by one constituent element. Moreover, you may abbreviate | omit a part of structure of the said embodiment. Further, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified only by the wording described in the claims are embodiments of the present invention.

  (7) In addition to the pump control device described above, a fuel supply system including the pump control device as a constituent element, a pump control program for causing a computer to function as the pump control device, a recording medium recording the pump control program, and a pump The present invention can also be realized in various forms such as a control method.

10: Fuel supply system, 18: Pressure sensor, 20: Fuel supply pump, 24: Cam, 26: Plunger, 30: Metering valve, 70: ECU (pump control device), 72: Pressure acquisition unit, 74: Angle detection Section, 76: control section, 200: fuel supply passage (fuel passage)

Claims (6)

A metering valve (30) adjusts the pumping amount of the fuel supply pump (20) that pumps the fuel sucked into the pressurizing chamber (100) to the engine by reciprocating movement of the plunger (26) driven by the rotation of the cam (24). A pump control device (70) applied to a fuel supply system for controlling and metering a pumping period in which fuel is pumped from the fuel supply pump in a pumping stroke by controlling energization to
A pressure acquisition unit (72, S402) for acquiring fuel pressure in the fuel passage from a pressure sensor (18) installed in a fuel passage (200) on the fuel suction side of the fuel supply pump;
When the plunger reciprocates, the actual angle of at least one of the top dead center and the bottom dead center of the plunger is detected based on the pressure pulsation generated in the fuel pressure acquired by the pressure acquisition unit. An angle detector (74, S400, S404, S410 to S432);
Based on the difference between the actual angle detected by the angle detector and the target angle of at least one of the top dead center and the bottom dead center corresponding to the actual angle, energization control for the metering valve A control unit (76, S408) for correcting
A pump control device comprising: The pump control device according to claim 1,
The angle detection unit detects the actual angle based on a pressure pulsation generated in the fuel pressure acquired by the pressure acquisition unit when energization to the metering valve is stopped.
Pump control device. The pump control device according to claim 1 or 2,
The angle detector (S400) is based on the pressure pulsation when the engine speed is equal to or less than the speed at which the next pressure pulsation does not occur before the pressure pulsation generated by the reciprocating movement of the plunger disappears. Detecting the actual angle;
Pump control device. The pump control device according to any one of claims 1 to 3,
The angle detection unit (S418, S426) is a period from a valve closing start command to the metering valve by energization control until a pressure pulsation generated on the fuel suction side disappears when the metering valve is closed. , The actual angle is not detected,
Pump control device. The pump control device according to any one of claims 1 to 4,
The angle detection unit (S420, S428) is based on the propagation delay of the pressure pulsation determined from at least one of the length of the fuel passage and the fuel property between the fuel supply pump and the pressure sensor. Correct the actual angle,
Pump control device. The pump control device according to any one of claims 1 to 5,
When detecting the actual angle of the top dead center, the angle detector (S428) lowers the pressure in the pressurizing chamber by opening the plunger from the top dead center and opens the metering valve. Correcting the actual angle of the top dead center based on a delay time until the valve
Pump control device.