JP4780051B2 - Fuel injection device for internal combustion engine - Google Patents

Description

  The present invention relates to a fuel injection device for an internal combustion engine (hereinafter, the internal combustion engine is referred to as an “engine”), and in particular, detects a sliding failure of a suction amount control valve that controls the amount of fuel sucked into a supply pump. The present invention relates to a fuel injection device for an internal combustion engine that performs control for eliminating sliding failure when sliding failure of an intake amount control valve is detected.

  Conventionally, a common rail fuel injection device is known as a fuel injection device for a diesel engine. A common rail type fuel injection device pressurizes fuel stored in a fuel tank with a supply pump, and stores the pressurized fuel in a pressure accumulation state on a common rail. An injector is connected to the common rail, and fuel stored in the common rail is injected from the injector to each cylinder of the engine body at a predetermined time.

  In such a common rail type fuel injection device, the pressure of the fuel stored in the common rail, that is, the pressure of the fuel injected from the injector has a great influence on the engine exhaust and the engine output. Therefore, in the common rail type fuel injection device, it is necessary to precisely control the pressure of the fuel stored in the common rail.

  The pressure of the fuel stored in the common rail is controlled by the amount of fuel discharged from the supply pump. The control unit of the fuel injection device sets a target pressure according to the operating state of the engine, and performs feedback control using the actual fuel pressure in the common rail detected by pressure detection means such as a pressure sensor. On the other hand, the amount of fuel discharged from the supply pump is controlled by a suction amount control valve provided on the suction side of the supply pump. Therefore, the control unit controls the actual pressure of the common rail by controlling the control current output to the suction amount control valve based on the detected actual pressure of the common rail.

The intake amount control valve includes, for example, a cylindrical case and a valve member that moves inside the case (see, for example, Patent Document 1). The case is formed in a cylindrical shape and has a first opening that penetrates the side wall in the radial direction. The valve member is also formed in a cylindrical shape and has a second opening that penetrates the side wall in the radial direction. When the electromagnetic drive unit drives the valve member in the axial direction, the area in which the first opening of the case and the second opening of the valve member overlap changes. In this way, the flow rate of the fuel passing through the first opening and the second opening is controlled by changing the area where the first opening and the second opening overlap with the movement of the valve member.
JP 2002-106740 A

  In the case of the intake amount control valve as disclosed in Patent Document 1, the case and the valve member slide. Therefore, a slight gap for ensuring relative movement is formed between the case and the valve member. However, if foreign matter contained in the fuel enters a slight gap formed between the case and the valve member, the sliding resistance between the case and the valve member increases, and the movement of the valve member is hindered. . Further, depending on the type of fuel or the substance contained in the fuel, the resistance during movement of the valve member may increase. If the movement of the valve member is hindered or the resistance during the movement of the valve member is increased as described above, the intake amount control valve is liable to slide. When sliding failure occurs in the intake amount control valve, the discharge characteristic of the supply pump with respect to the control current output to the intake amount control valve changes. As a result, there is a problem that precise control of the actual fuel pressure in the common rail becomes difficult.

  Accordingly, an object of the present invention is to detect a sliding failure between the case of the intake amount control valve and the valve member, and to perform control for eliminating the sliding failure when the sliding failure is detected, and An object of the present invention is to provide a fuel injection device for an internal combustion engine that precisely controls the actual pressure of the fuel.

  According to the first aspect of the present invention, when a sliding failure is detected between the case of the suction amount control valve and the valve member by the sliding state detection means, the failure elimination control means detects the sliding state between the case and the valve member. Eliminate defects. The defect elimination control means urges the discharge of foreign matter that has entered between the case and the valve member, for example, by changing the control amount of the suction amount control valve, that is, the movement amount of the valve member. Thereby, the sliding failure of the intake amount control valve is eliminated. Therefore, for example, by detecting the sliding failure of the intake amount control valve and eliminating the sliding failure before the actual fuel pressure in the common rail decreases and the engine operation due to the decrease in the actual pressure is affected. The actual fuel pressure in the common rail can be precisely controlled without affecting the operation of the engine.

According to the first aspect of the present invention, the sliding state detecting means detects a sliding failure of the intake amount control valve based on the fuel pressure in the common rail. That is, the sliding state detection means detects the difference between the set target pressure and the actual pressure. When the number of times that the difference becomes equal to or greater than a predetermined value is more than once within a predetermined period, the sliding state detecting means determines that a sliding failure has occurred. When a sliding failure occurs between the case and the valve member, the difference between the amount of fuel supplied from the suction amount control valve to the supply pump and a predetermined amount corresponding to the target pressure increases. For this reason, when a sliding failure occurs, the difference between the set target pressure and the actual pressure detected by the pressure detection means becomes a predetermined value or more. On the other hand, depending on the operation state, when the difference between the target pressure and the actual pressure occurs, the intake amount control valve does not always have a sliding failure. Therefore, the sliding state detecting means determines that the sliding state between the case and the valve member is defective when the difference between the target pressure and the actual pressure is a predetermined value or more within a predetermined period. To do. Therefore, the sliding state between the case and the valve member can be detected with high accuracy.

Furthermore, in the invention described in claim 1 , the failure elimination control means changes the control to a side where at least one of the movement amount or the movement force of the valve member increases. By increasing at least one of the moving amount or the moving force of the valve member, the elimination of the sliding failure between the valve member and the case is promoted. Therefore, before the actual pressure of the fuel in the common rail is reduced, the sliding failure of the intake amount control valve can be eliminated, and the actual pressure of the common rail can be precisely controlled.

Further, in the first aspect of the present invention, even if the failure elimination control means changes the control to a side where at least one of the movement amount or the movement force of the valve member increases, the sliding failure between the valve member and the case will not occur. When the problem is not solved, the control is further changed to the side where at least one of the moving amount and the moving force of the valve member decreases. As described above, after increasing at least one of the moving amount or moving force of the valve member and decreasing it, the sliding failure between the valve member and the case is eliminated, and then the moving amount or moving force of the valve member is reduced. It is possible to reduce at least one of the values until an optimum value is reached. Therefore, before the actual pressure of the fuel in the common rail is reduced, the sliding failure of the intake amount control valve can be eliminated, and the actual pressure of the common rail can be precisely controlled.

According to the second aspect of the present invention, the defect elimination control means changes the control gain for the intake amount control valve. Thereby, at least one of the moving amount or the moving force of the valve member changes in accordance with the changed control gain. Therefore, the sliding failure of the intake amount control valve can be eliminated by a simple control of changing the control gain.

According to a third aspect of the present invention, the failure elimination control means changes the ON period of the pulsed control signal for the intake amount control valve, particularly the ON period in the transition period. Thereby, at least one of the moving amount and the moving force of the valve member changes according to the changed ON period. Therefore, the sliding failure of the intake amount control valve can be eliminated by a simple control of changing the ON period.

In the invention described in claim 4 , the defect elimination control means changes the assist amount during the ON period of the pulsed control signal. Thereby, the ON period of the pulsed control signal is extended or shortened according to the assist amount. In the invention described in claim 5 , the defect elimination control means changes the frequency of the pulsed control signal. Thereby, the ON period of the pulsed control signal is extended or shortened according to the frequency. Therefore, the ON period of the control signal can be easily changed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Configuration of fuel injection device)
First, a fuel injection device according to an embodiment of the present invention will be described. FIG. 1 is a schematic view showing a fuel injection device 10 according to an embodiment of the present invention. The fuel injection device 10 of the present embodiment is a common rail fuel injection device 10 and is applied to a diesel engine. The fuel injection device 10 includes a fuel tank 11, a suction amount control valve (SCV) 30, a supply pump 12, a common rail 13, an injector 14, and an engine control device (hereinafter referred to as “ECU: Engine Control Unit”) 15 as a control device. , And an electronic drive unit (hereinafter referred to as “EDU: Electronic Drive Unit”) 16. The suction amount control valve 30 and the supply pump 12 constitute an integral pump unit 17.

  The fuel tank 11 stores normal pressure fuel. The fuel inside the fuel tank 11 is supplied to a suction amount control valve 30 via a suction pipe portion 21 by a low-pressure pump (not shown). The supply pump 12 pressurizes fuel sucked into a pressurizing chamber (not shown) by reciprocating a plunger (not shown). In the supply pump 12, the flow rate of the discharged fuel changes according to the flow rate of the fuel sucked into the pressurizing chamber. Driving force is transmitted to the plunger by a crankshaft of a diesel engine (not shown). The fuel pressurized by the supply pump 12 is discharged to the common rail 13. A fuel pipe 22 is connected to the discharge side of the supply pump 12. The fuel piping unit 22 connects the supply pump 12 and the common rail 13.

  The common rail 13 is connected to the fuel pipe section 22 and stores the fuel pressurized by the supply pump 12 in a pressure accumulation state. An injector 14 that injects fuel into each cylinder of the diesel engine is connected to the common rail 13 according to the number of cylinders. The fuel stored in the common rail 13 in a pressure accumulation state is injected from the injector 14. A reflux piping unit 23 is connected to the supply pump 12, the common rail 13, and the injector 14. The surplus fuel in the supply pump 12, the common rail 13, and the injector is returned to the fuel tank 11 via the return pipe portion 23.

  The ECU 15 is composed of, for example, a microcomputer having a CPU, a ROM, and a RAM. The CPU controls the entire diesel engine system including the fuel injection device 10 in accordance with a computer program stored in the ROM. In the ECU 15, a pressure sensor 24, an accelerator sensor 25, a rotation speed sensor 26, and the like are connected to a circuit on the input side. The pressure sensor 24 is provided on the common rail 13. The pressure sensor 24 detects the actual pressure of the fuel stored in the common rail 13. Hereinafter, the actual pressure of the fuel stored in the common rail 13 is referred to as “actual rail pressure”.

  The pressure sensor 24 outputs the detected actual rail pressure to the ECU 15 as an electrical signal. The accelerator sensor 25 detects the amount of depression of an accelerator pedal (not shown). The accelerator sensor 25 outputs the detected accelerator pedal depression amount Ac to the ECU 15 as an electrical signal. The rotational speed sensor 26 detects the rotational speed of a crankshaft of a diesel engine (not shown). The rotation speed sensor 26 outputs the detected rotation speed Ne of the diesel engine to the ECU 15 as an electric signal.

  The ECU 15 determines the diesel engine from the rotational speed Ne of the diesel engine detected by the rotational speed sensor 26, the fuel injection amount Qf output from the injector 14 output to the EDU 16, and the accelerator pedal depression amount Ac detected by the accelerator sensor 25, for example. Detect the operating state. The ECU 15 sets the injection amount of fuel injected from the injector 14 in accordance with the detected operating state of the diesel engine. The ECU 15 sets the fuel pressure required in the common rail 13 based on the set fuel injection amount. Hereinafter, the value that the ECU 15 sets as the fuel pressure in the common rail 13 in accordance with the operating state of the diesel engine is referred to as “target rail pressure”.

In the ECU 15, the relief valve 27, the intake amount control valve 30, the EDU 16, and the like are connected to the circuit on the output side. The relief valve 27 is provided on the common rail 13. The relief valve 27 opens when the actual rail pressure of the common rail 13 detected by the pressure sensor 24 becomes higher than a predetermined upper limit value. Thereby, the pressure resistance of the common rail 13 is ensured. The fuel discharged as the relief valve 27 is opened is returned to the fuel tank 11 via the recirculation pipe section 23. The intake amount control valve 30 controls the flow rate of the fuel supplied to the supply pump 12 based on the control current output from the ECU 15. The EDU 16 is connected to the electromagnetic valve 18 of the injector 14. The EDU 16 outputs a drive signal to the electromagnetic valve 18 of the injector 14 based on the drive signal output from the ECU 15. In the injector 14, the electromagnetic valve 18 is driven based on the drive signal output from the EDU 16, and fuel injection is intermittently performed. As a result, the injector 14 injects the fuel stored in the common rail 13 into each cylinder of the diesel engine.
The ECU 15 constitutes a pressure setting means in the claims, and constitutes a pressure detection means together with the pressure sensor 24. Thereby, ECU15 comprises the sliding state detection means. Moreover, ECU15 comprises the defect elimination control means in a claim.

Next, the configuration of the intake amount control valve 30 will be described in detail.
As shown in FIG. 2, the intake amount control valve 30 includes a case 31, a valve member 32, and an electromagnetic drive unit 50. In the present embodiment, the intake amount control valve 30 is a normally open type in which the flow of fuel is allowed when the supply of power to the electromagnetic drive unit 50 is stopped. The inner diameter of the case 31 is slightly larger than the outer diameter of the valve member 32. Thereby, a slight gap is formed between the case 31 and the valve member 32, and the valve member 32 is slidably held by the case 31.

  The case 31 is formed in a substantially cylindrical shape, and accommodates a valve member 32 therein so as to be slidable back and forth. The case 31 has an opening 33 as a first opening that penetrates the cylindrical side wall in the radial direction. A plurality of openings 33 are provided in the circumferential direction of the case 31. The opening 33 is connected to the pressurizing chamber of the supply pump 12 via a passage portion (not shown). The case 31 is open at one end in the axial direction, that is, the end on the fuel tank 11 side. The open end portion of the case 31 is connected to the fuel tank 11 via the suction pipe portion 21.

  The valve member 32 is formed in a substantially cylindrical shape, and is accommodated in the case 31 so as to be slidable in the axial direction. The tubular valve member 32 forms a fuel passage 34 on the inner peripheral side. The valve member 32 has a port 35 that penetrates the cylindrical side wall in the radial direction. Further, the valve member 32 has a fuel groove 36 connected to the outer peripheral end of the port 35 on the outer wall side. A plurality of ports 35 and fuel grooves 36 are provided in the circumferential direction of the valve member 32. The port 35 and the fuel groove 36 constitute a second opening in the claims. As the valve member 32 moves in the axial direction, that is, the left-right direction in FIG. 2, the area where the fuel groove 36 and the opening 33 overlap is changed. By changing the overlapping area of the fuel groove 36 and the opening 33, the opening area through which the fuel flowing from the fuel passage 34 to the opening 33 can pass changes. As a result, the flow rate of the fuel passing through the intake amount control valve 30 changes from fully open to fully closed according to the axial position of the valve member 32.

  A bush 37 and a spring 38 are provided inside the case 31. The bush 37 is fixed to the end of the case 31 on the fuel tank 11 side. The bush 37 can contact the end of the valve member 32 opposite to the spring 38. The movement of the valve member 32 toward the fuel tank 11 is restricted by contacting the bush 37. The spring 38 is accommodated in a spring chamber 39 formed between the case 31 and the valve member 32. One end of the spring 38 in the axial direction is in contact with the end of the valve member 32 opposite to the bush 37, and the other end is in contact with the bottom 41 of the case 31. The bottom 41 of the case 31 closes the opposite side of the cylindrical case 31 from the fuel tank 11. The spring 38 has a force extending in the axial direction. Thereby, the valve member 32 is pressed against the bush 37 by the spring 38.

  The electromagnetic drive unit 50 includes a stator 51 and a coil 52. The stator 51 is made of a magnetic material. The case 31 and the valve member 32 are also formed of a magnetic material. The coil 52 is provided between the case 31 and the stator 51. The coil 52 is wound around a spool 53 made of an insulator such as resin. The control current output from the ECU 15 is supplied to the coil 52 via the terminal 54. When the coil 52 is energized from the ECU 15, a magnetic circuit is formed in the case 31 and the stator 51 that surround the coil 52. Since the case 31 has the thin portion 42 in a part in the axial direction, a part of the magnetic flux flowing through the magnetic circuit leaks to the valve member 32. Thus, when the coil 52 is energized, a magnetic attractive force is generated between the suction part 43 formed on the bottom 41 side of the thin part 42 and the valve member 32 in the case 31.

  When the coil 52 is energized as described above, a magnetic attractive force is generated between the suction portion 43 and the valve member 32. Therefore, the valve member 32 moves to the suction portion 43 side against the pressing force of the spring 38. As the valve member 32 moves toward the suction part 43, the area where the fuel groove 36 and the opening 33 overlap is reduced. Thereby, the flow rate of the fuel supplied to the supply pump 12 is reduced. When the control current to the coil 52 reaches the maximum, the supply of fuel to the supply pump 12 is stopped.

  On the other hand, when the energization to the coil 52 is stopped, the magnetic attractive force between the attraction portion 43 and the valve member 32 disappears. Therefore, the valve member 32 moves to the bush 37 side by the pressing force of the spring 38. As the valve member 32 moves to the bush 37 side, the area where the fuel groove 36 and the opening 33 overlap is increased. Thereby, the flow rate of the fuel supplied to the supply pump 12 increases. When the control current to the coil 52 becomes 0, the flow rate of the fuel supplied to the supply pump 12 becomes maximum.

  Thus, the magnetic attraction force applied to the valve member 32 changes as the control current supplied to the coil 52 changes. The valve member 32 stops at a position where the magnetic attractive force and the pressing force of the spring 38 are balanced. Therefore, when the control current supplied to the coil 52 changes, the area where the fuel groove 36 and the opening 33 overlap is changed, and the amount of fuel supplied to the supply pump 12 changes. As the flow rate of the fuel supplied to the supply pump 12 changes, the fuel pressure in the common rail 13 changes. That is, the ECU 15 controls the flow rate of fuel discharged from the supply pump 12 to the common rail 13 and the pressure of fuel in the common rail 13 by controlling the intake amount control valve 30 with control currents set based on various parameters. ing.

Next, the operation of the fuel injection device 10 having the above configuration will be described.
(Sliding failure detection)
First, detection of a sliding failure between the case 31 of the intake amount control valve 30 and the valve member 32 will be described with reference to FIG. The ECU 15 detects sliding failure according to a computer program stored in the ROM. The ECU 15 is activated when an ignition switch of a vehicle on which the fuel injection device 10 is mounted is turned on and power is supplied from a battery (not shown). The ECU 15 determines a sliding failure at the time of starting or at a predetermined time after the starting. Moreover, ECU15 is good also as a structure which implements determination of sliding failure after an ignition switch is turned off, and turns off a power supply after that.

When the detection of the sliding failure is started, the ECU 15 sets the initial value to 0 (S101). Here, the initial values set by the ECU 15 are the large deviation determination count N and the determination time interval DT. Therefore, the ECU 15 sets N = 0 and DT = 0. The large deviation determination count N and the determination time interval DT will be described later.
When the ECU 15 sets an initial value in step S101, the ECU 15 increments the determination time interval DT by one (S102). That is, the ECU 15 sets DT = DT + 1. As described above, every time the sliding failure shown in FIG. 3 is detected, the determination time interval DT is incremented by “1”.

  When the ECU 15 proceeds to count the determination time interval DT in step S102, the ECU 15 determines the operating condition of the diesel engine on which the fuel injection device 10 is mounted (S103). That is, the ECU 15 determines whether or not the operating condition of the diesel engine is in a stable state suitable for detecting a sliding failure of the intake amount control valve 30. When detecting a sliding failure, the flow rate of the fuel discharged from the supply pump 12 to the common rail 13 is changed. For this reason, when the diesel engine is in a high load state, an acceleration state or a deceleration state, for example, if the sliding failure is detected and the sliding failure elimination control is performed, the flow rate of the fuel discharged to the common rail 13 changes suddenly. The actual rail pressure at 13 may be insufficient or excessive. Therefore, the ECU 15 determines whether or not the diesel engine is in a stable operation state prior to detecting the sliding failure.

  The ECU 15 determines whether the diesel engine is based on the rotational speed Ne of the diesel engine detected by the rotational speed sensor 26, the fuel injection amount Qf output from the injector 14 output to the EDU 16, the accelerator pedal depression amount Ac detected by the accelerator sensor 25, and the like. It is determined whether or not the vehicle is in a stable operating state. Specifically, the rotational speed Ne is between the predetermined lower limit Ne1 and the upper limit Ne2, the fuel injection amount Qf is between the predetermined lower limit Qf1 and the upper limit Qf2, and the accelerator pedal depression amount Ac is the predetermined lower limit. If it is between Ac1 and the upper limit Ac2, the ECU 15 determines that the diesel engine is in a stable operating state. Although the example in which the rotational speed Ne, the fuel injection amount Qf, and the stepping amount Ac are applied to the determination of the operation state of the diesel engine has been shown, these are examples, and the ECU 15 includes other various elements of the diesel engine. The operating state may be determined.

  When the ECU 15 determines in step S103 that the diesel engine is not in a stable operating state, the ECU 15 returns to step S102 and repeats step S102 and subsequent steps.

When the ECU 15 determines in step S103 that the diesel engine is in a stable operating state, the ECU 15 performs a target rail pressure condition determination (S104). That is, the ECU 15 determines whether or not the operation state of the diesel engine is stable and the change in the target rail pressure in the common rail 13 is within a predetermined range. Even if the operation state of the diesel engine is stable, the target rail pressure may change due to, for example, a change in the amount of fuel discharged from the supply pump 12. Therefore, the ECU 15 determines whether or not the change in the target rail pressure is within a predetermined range. Specifically, the ECU 15 determines that the absolute value of the difference between the currently set target rail pressure Pf (i) and the target rail pressure Pf (i−1) set in the previous processing flow is predetermined. It is calculated whether it is smaller than the predetermined value Pfd.
The ECU 15 determines that the target rail pressure is stable when the absolute value of the difference between the target rail pressures is smaller than the predetermined value Pfd. On the other hand, the ECU 15 determines that the target rail pressure is not stable when the absolute value of the difference between the target rail pressures is equal to or greater than the predetermined value Pfd, and returns to step S102.

  When ECU 15 determines that the target rail pressure is stable in step S104, ECU 15 performs a large deviation determination from the actual rail pressure and the target rail pressure (S105). That is, the ECU 15 calculates a deviation between the actual rail pressure NPc (i) of the common rail 13 detected by the pressure sensor 24 and the target rail pressure Pf (i) set according to the operation state of the diesel engine. The ECU 15 has a large deviation between the actual rail pressure and the target rail pressure when the absolute value of the difference between the calculated actual rail pressure NPc (i) and the target rail pressure Pf (i) is larger than the predetermined value Pcd. Is determined. The target rail pressure is not limited to a value set according to the operating state of the diesel engine, and the ECU 15 may set a predetermined value for detecting a sliding failure.

  As described above, the suction amount control valve 30 slides with the valve member 32 supported by the case 31. Therefore, a slight gap is secured between the valve member 32 and the case 31. On the other hand, a part of the fuel that has flowed from the fuel tank 11 into the intake amount control valve 30 flows out to the supply pump 12 via the port 35 and the opening 33, and the rest remains in the spring chamber 39. For this reason, when the fuel contains fine foreign matter, the foreign matter tends to stay in the spring chamber 39 together with the fuel. If the foreign matter contained in the fuel enters the gap between the valve member 32 and the case 31 for some reason, the sliding resistance between the valve member 32 and the case 31 increases. In recent years, fuels not derived from petroleum such as vegetable oils are being used as diesel engine fuels. Therefore, depending on the additive contained in the fuel or the physical properties of the fuel itself, the sliding resistance between the valve member 32 and the case 31 may increase, and the smooth sliding of the valve member 32 may be hindered.

  As described above, when the sliding resistance increases and the smooth sliding between the valve member 32 and the case 31 is hindered, the suction amount control valve corresponds to the control current output from the ECU 15 to the coil 52 of the suction amount control valve 30. The accuracy of the flow rate of the fuel supplied from 30 to the supply pump 12 decreases. The actual rail pressure of the common rail 13 is determined by the flow rate of fuel supplied from the supply pump 12, that is, the flow rate of fuel supplied from the intake amount control valve 30 to the supply pump 12.

  Therefore, if a sliding failure occurs between the valve member 32 and the case 31, the controllability of the fuel flow rate by the intake amount control valve 30 deteriorates, and the flow rate of fuel discharged from the supply pump 12 to the common rail 13. As a result, the controllability of the actual rail pressure of the common rail 13 deteriorates. Therefore, the ECU 15 calculates the absolute value, that is, the deviation of the difference between the actual rail pressure NPc (i) detected by the pressure sensor 24 and the set target rail pressure Pf (i), and the deviation is larger than the predetermined value Pfd. The deviation is determined to be large, and it is determined that there is a high possibility that a sliding failure has occurred.

If the ECU 15 determines in step S105 that the deviation between the actual rail pressure NPc (i) and the target rail pressure Pf (i) is larger than Pcd, the ECU 15 advances the count of the large deviation determination count N by one (S106). Here, the large deviation determination count N means the number of times that the deviation between the actual rail pressure and the target rail pressure is determined to be large in step S105. On the other hand, if ECU15 determines with the deviation computed in step S105 being Pcd or less, it will return to step S102.
When the count of the large deviation determination number N is incremented by one in step S106, the ECU 15 determines whether or not the counted large deviation determination number N is greater than a predetermined value N1 (S107). The ECU 15 returns to step S102 when the large deviation determination count N is equal to or less than the predetermined value N1 in step S107.

  If the ECU 15 determines in step S107 that the large deviation determination count N is greater than the predetermined value N1, the ECU 15 determines whether the determination time interval DT is shorter than the predetermined value DT1 (S108). As described above, when a sliding failure occurs between the valve member 32 and the case 31, the flow rate accuracy of the fuel supplied from the intake amount control valve 30 to the supply pump 12 deteriorates, and the actual rail pressure of the common rail 13 Deviation from the target rail pressure increases. On the other hand, when a sliding failure occurs, the period during which the deviation between the actual rail pressure and the target rail pressure increases is increased. That is, when a sliding failure occurs, the phenomenon that the deviation between the actual rail pressure and the target rail pressure increases is not temporary but continues. Therefore, when the determination time interval DT until the large deviation determination count N becomes larger than the predetermined value N1 is shorter than the predetermined value DT1, the sliding failure of the intake amount control valve 30 is continuously generated in a short time. Conceivable.

  Therefore, when the determination time interval DT is shorter than the predetermined value DT1 in step S108, the ECU 15 determines that a sliding failure has occurred in the intake amount control valve 30 (S109). On the other hand, when the determination time interval DT is equal to or greater than the predetermined value DT1, the ECU 15 determines that the sliding failure has not continued or has been eliminated, and repeats the process from the beginning, that is, step S101.

  In the above-described detection of the sliding failure, when the determination time interval DT at which the large deviation determination count N is greater than the predetermined value N1 is shorter than the predetermined value DT1, the occurrence of a sliding failure of the intake amount control valve 30 is detected. An example was described. However, when the determination time interval DT reaches the predetermined value DT1, the occurrence of a sliding failure may be detected if the large deviation determination count N reaches the predetermined value N1.

  By the above procedure, a sliding failure occurring between the valve member 32 of the suction amount control valve 30 and the case 31 is detected. The sliding failure of the intake amount control valve 30 is detected from the deviation between the target rail pressure set by the ECU 15 and the actual rail pressure detected by the pressure sensor 24. The ECU 15 and the pressure sensor 24 are always provided in the fuel injection device 10. Therefore, it is possible to detect a sliding failure of the suction amount control valve 30 at an early stage without incurring additional parts.

(First embodiment of sliding failure elimination control)
When the ECU 15 determines that a sliding failure has occurred in the suction amount control valve 30 by the above-described procedure, the ECU 15 performs the sliding failure elimination control according to the procedure shown in FIG. 4 in order to eliminate the sliding failure.
The ECU 15 determines whether or not a sliding failure has occurred in the suction amount control valve 30 by the procedure shown in FIG. 3 (S201). If the ECU 15 determines that there is no sliding failure in the intake amount control valve 30, it repeats the process from the beginning. When the ECU 15 determines that a sliding failure has occurred in the intake amount control valve 30, the ECU 15 increases the control gain of the feedback control (S202).

  As shown in FIG. 5, the ECU 15 calculates a proportional term P, an integral term I, and a differential term D based on the actual rail pressure and the target rail pressure, and calculates the fuel based on the pressure deviation between the actual rail pressure and the target rail pressure. The discharge amount is converted. That is, the ECU 15 performs feedback control of the fuel discharge amount from the supply pump 12, that is, the intake amount control valve 30. The ECU 15 converts the fuel discharge amount into a control current by adding the fuel injection amount in the injector 14 and the fuel leakage amount from the injector 14 and the common rail 13 to the converted fuel discharge amount. . As a result, the ECU 15 calculates a target control current Ip to be output to the intake amount control valve 30.

  Here, the ECU 15 increases the control gain of the proportional term P, the integral term I, and the derivative term D calculated based on the actual rail pressure and the target rail pressure. More specifically, the ECU 15 sets a new proportional term control gain Gp by adding the increase gain Gpd to the calculated proportional term control gain Gp. Similarly, the ECU 15 sets the new integral term control gain Gd by adding the increased gain Gid to the calculated integral term control gain Gi, and adds the increased gain Gdd to the differential term control gain Gd to obtain the new Gd. Set.

  When the control gain is increased in step S202, the ECU 15 determines again whether or not the sliding failure of the intake amount control valve 30 has been resolved (S203). If the ECU 15 determines in step S203 that the sliding failure of the suction amount control valve 30 has been eliminated, the ECU 15 repeats the process from the beginning. On the other hand, if the ECU 15 determines in step S203 that the sliding failure of the suction amount control valve 30 has not been eliminated, the ECU 15 determines whether or not the control gain increased in step S202 is within an allowable range (S204).

  By increasing the control gain, the control current output from the ECU 15 to the intake amount control valve 30 increases. Therefore, the magnetic attractive force generated between the valve member 32 and the attracting part 43 increases, and the moving force and the moving amount of the valve member 32 increase. Thereby, the sliding failure between case 31 and valve member 32 becomes easy to be eliminated. When the sliding failure is eliminated, the sliding failure of the suction amount control valve 30 is not detected in step S203. As the control gain is increased, the elimination of the sliding failure is promoted. On the other hand, if the control gain is increased indefinitely, excessive movement may occur in the valve member 32, or excessive force may be applied to the valve member 32, resulting in damage to the intake amount control valve 30 and the like.

  Therefore, the ECU 15 determines whether or not the increased control gain is equal to or greater than the upper limit of the allowable range in step S204 while increasing the control gain. When the control gain is smaller than the upper limit of the allowable range in step S204, the ECU 15 returns to step S202 and further increases the control gain. That is, the ECU 15 increases the control gain until the control gain reaches the upper limit of the allowable range when the sliding failure of the intake amount control valve 30 is not eliminated.

  On the other hand, when the ECU 15 determines in step S204 that the increased control gain is equal to or greater than the upper limit of the allowable range, the ECU 15 decreases the control gain of the feedback control (S205). The ECU 15 subtracts the decrease gain Gpd from the calculated proportional term control gain Gp to set a new proportional term control gain Gp, subtracts the decrease gain Gid from the integral term control gain Gi, and sets a new integral term control gain. Gi is set, and the control gain Gd of the new differential term is set by subtracting the decrease gain Gdd from the control gain Gd of the differential term.

  When the control gain is decreased in step S205, the ECU 15 determines again whether or not the sliding failure of the intake amount control valve 30 has been resolved (S206). If the ECU 15 determines in step S206 that the sliding failure of the suction amount control valve 30 has been resolved, the ECU 15 repeats the process from the beginning. On the other hand, if the ECU 15 determines in step S206 that the sliding failure of the intake amount control valve 30 has not been eliminated, the ECU 15 determines whether or not the reduced control gain is within an allowable range (S207).

  By reducing the control gain, the control current output from the ECU 15 to the intake amount control valve 30 is reduced. Therefore, the magnetic attractive force generated between the valve member 32 and the suction portion 43 is reduced, and the movement amount of the valve member 32 is reduced. As described above, the sliding failure between the case 31 and the valve member 32 is easily resolved by the increase or decrease of the movement force or the movement amount of the valve member 32 accompanying the increase or decrease of the control gain. When the sliding failure is eliminated, the sliding failure of the suction amount control valve 30 is not detected in step S206. On the other hand, if the control gain is reduced indefinitely, it may be difficult to control the fuel flow rate.

  Therefore, the ECU 15 determines whether or not the decreased control gain is equal to or lower than the lower limit of the allowable range in step S207 while decreasing the control gain. When the control gain is larger than the lower limit of the allowable range in step S207, the ECU 15 returns to step S205 and further decreases the control gain. That is, the ECU 15 decreases the control gain until the control gain reaches the lower limit of the allowable range when the sliding failure of the intake amount control valve 30 is not eliminated.

  When the ECU 15 determines in step S207 that the reduced control gain is less than or equal to the lower limit of the allowable range, the sliding failure of the intake amount control valve 30 is not resolved, and the supply pump 12 including the intake amount control valve 30 is A failure is determined (S208). And ECU15 memorize | stores failure determination (S209), and implements a fail safe treatment (S210). The ECU 15 stores the failure determination in, for example, a nonvolatile memory that can be written as needed. In addition, as a fail-safe measure, the ECU 15 displays a fuel system failure on the dashboard of the vehicle, or warns the vehicle occupant of the failure by other audible or visual warnings. Further, the ECU 15 may perform a so-called limp home treatment for ensuring the minimum travel of the vehicle, for example, as the fail safe treatment.

  As described above, in the first embodiment of the sliding failure elimination control, when the control current output from the ECU 15 to the intake amount control valve 30 is feedback-controlled, the gain amount of the feedback gain is increased or decreased. As a result, sliding between the case 31 of the suction amount control valve 30 and the valve member 32 is promoted, and the sliding failure is eliminated. Further, after at least one of the movement amount or the movement force of the valve member 32 is increased and then decreased, the sliding failure between the valve member 32 and the case 31 is eliminated, and then the movement amount of the valve member 32 or At least one of the moving forces can be reduced to an optimal value. Therefore, it is possible to quickly eliminate the sliding failure before the influence such as the pressure drop of the fuel supplied to the injector 14 occurs.

(Second embodiment of sliding failure control)
In the second embodiment, the ECU 15 changes the duty assist amount of the pulsed control current according to the flow shown in FIG. 6 instead of changing the control gain in the first embodiment. Hereinafter, in the second embodiment, differences from the first embodiment will be mainly described, and description of matters common to the first embodiment will be omitted.

  The ECU 15 determines whether or not a sliding failure has occurred in the intake amount control valve 30 by the procedure shown in FIG. 3 (S301). Then, the ECU 15 repeats the process from the beginning when no sliding failure has occurred, and increases the duty assist amount of the drive current when determining that the sliding failure has occurred (S302).

  Based on the control current Ip calculated or set by the logic circuit shown in FIG. 5, the ECU 15 generates a control pulse for the control current of the intake amount control valve 30 as shown in FIG. Specifically, the ECU 15 calculates the fuel intake cycle in the supply pump 12 from the pulsed rotation pulse output from the rotation speed sensor 26, and outputs to the intake amount control valve 30 based on the calculated fuel intake cycle. Calculate the current period. Then, the ECU 15 calculates the duty ratio of the pulsed control signal from the calculated control current cycle. The ECU 15 calculates a duty assist amount from the target control current Ip and the calculated duty ratio, generates a final control pulse, and outputs it to the intake amount control valve 30.

  Here, the ECU 15 changes the duty D of the control current, that is, the ON period, based on the calculated duty assist amount Das. As shown in FIG. 8A, the control current is set in a pulse shape that periodically turns on and off. As shown in FIG. 8A, the period from the rise of the pulsed control current to the next rise is the control current cycle. The period from the rising edge to the falling edge of the control current is the ON period. The normal control current is repeatedly turned on and off at a constant cycle as shown in FIG.

  On the other hand, when the control current output from the ECU 15 to the intake amount control valve 30 changes due to, for example, a change in the target rail pressure, in the so-called transition period, as shown in FIG. It changes from Du1 to Du2. FIG. 8B shows an example of a transition period when the control current increases. As the on-period of the control current changes from Du1 to Du2, the cycle of the control current also changes. The ECU 15 extends the ON period of the control current by adding the set duty assist amount Das to the pulsed control current. In particular, in the case of the second embodiment, the ECU 15 adds the duty assist amount Das during a transition period in which the ON period of the control current changes from Du1 to Du2.

  When the duty assist is performed in step S302, the ECU 15 determines whether or not the sliding failure of the intake amount control valve 30 has been resolved (S303). If the ECU 15 determines in step S303 that the sliding failure of the suction amount control valve 30 has been resolved, the ECU 15 repeats the process from the beginning. On the other hand, if the ECU 15 determines in step S303 that the sliding failure of the intake amount control valve 30 has not been eliminated, the ECU 15 determines whether or not the ON period in which the duty assist is performed is within an allowable range (S304).

  By performing duty assist, the average value of the control current output from the ECU 15 to the intake amount control valve 30 increases. Therefore, the moving force applied to the valve member 32 and the moving amount of the valve member 32 increase. Thereby, although elimination of the sliding failure between the case 31 and the valve member 32 is promoted, a load applied to the valve member 32 and the electromagnetic drive unit 50 increases. Therefore, the ECU 15 determines whether the duty assist amount is equal to or greater than the upper limit of the allowable range in step S304 while performing duty assist. When the duty assist amount is smaller than the upper limit of the allowable range in step S304, the ECU 15 returns to step S302 to increase the duty assist amount. That is, the ECU 15 increases the duty assist amount until the duty assist amount reaches the upper limit of the allowable range when the sliding failure of the intake amount control valve 30 is not eliminated.

  On the other hand, when the ECU 15 determines in step S304 that the duty assist amount is equal to or greater than the upper limit of the allowable range, the ECU 15 decreases the duty assist amount (S305). Even when the duty assist amount is decreased, only the duty assist amount Das in the transition period may be changed. The ECU 15 shortens the ON period of the control current by decreasing the duty assist amount. When the duty assist amount is decreased in step S305, the ECU 15 determines again whether the sliding failure of the intake amount control valve 30 has been resolved (S306). If the ECU 15 determines in step S207 that the sliding failure of the suction amount control valve 30 has been resolved, the ECU 15 repeats the process from the beginning. On the other hand, if the ECU 15 determines in step S306 that the sliding failure of the intake amount control valve 30 has not been eliminated, the ECU 15 determines whether or not the ON period in which the duty assist is performed is within an allowable range (S307).

By performing the duty assist, the average value of the control current output from the ECU 15 to the intake amount control valve 30 decreases. Therefore, although the elimination of the sliding failure between the case 31 and the valve member 32 is promoted, the load applied to the valve member 32 and the electromagnetic drive unit 50 increases. Therefore, the ECU 15 determines whether or not the duty assist amount is equal to or lower than the lower limit of the allowable range in step S307 while performing duty assist. When the duty assist amount is larger than the lower limit of the allowable range in step S306, the ECU 15 returns to step S305 and decreases the duty assist amount. That is, the ECU 15 decreases the duty assist amount until the duty assist amount reaches the lower limit of the allowable range when the sliding failure of the intake amount control valve 30 is not eliminated.
When the ECU 15 determines in step S307 that the duty assist amount is less than or equal to the lower limit of the allowable range, the ECU 15 determines that the sliding failure is not resolved and the supply pump 12 including the intake amount control valve 30 is faulty (S308). And ECU15 memorize | stores failure determination (S309), and implements a fail safe treatment (S310).

  As described above, in the second embodiment of the sliding failure elimination control, when the control current output from the ECU 15 to the intake amount control valve 30 is feedback controlled, the ON period of the pulsed control current is set by performing duty assist. It is stretched. As a result, sliding between the case 31 of the suction amount control valve 30 and the valve member 32 is promoted, and the sliding failure is eliminated. Therefore, it is possible to quickly eliminate the sliding failure before the influence such as the pressure drop of the fuel supplied to the injector 14 occurs.

(Third embodiment of sliding failure control)
In the third embodiment, the ECU 15 changes the duty frequency of the pulsed control current as shown in FIG. 9 instead of changing the control gain in the first embodiment. Hereinafter, the third embodiment will be described with a focus on differences from the first embodiment or the second embodiment, and a description common to the first embodiment or the second embodiment will be omitted.

The ECU 15 determines whether or not a sliding failure has occurred in the intake amount control valve by the procedure shown in FIG. 3 (S401). The ECU 15 repeats the process from the beginning when no sliding failure has occurred, and increases the duty frequency of the drive current when determining that the sliding failure has occurred (S402).
When the duty frequency of the control current is increased in step S402, the ECU 15 determines whether or not the sliding failure of the intake amount control valve 30 has been resolved (S403). If the ECU 15 determines in step S403 that the sliding failure of the suction amount control valve 30 has been resolved, the ECU 15 repeats the process from the beginning. On the other hand, if the ECU 15 determines in step S403 that the sliding failure of the intake amount control valve 30 has not been eliminated, the ECU 15 determines whether or not the duty frequency is within an allowable range (S404).

  By increasing the duty frequency, the average value of the control current output from the ECU 15 to the intake amount control valve 30 increases. Therefore, the moving force applied to the valve member 32 and the moving amount of the valve member 32 increase. Thereby, although elimination of the sliding failure between the case 31 and the valve member 32 is promoted, a load applied to the valve member 32 and the electromagnetic drive unit 50 increases. Therefore, the ECU 15 determines whether or not the duty frequency is equal to or higher than the upper limit of the allowable range in step S404 while changing the duty frequency. When the duty frequency is smaller than the upper limit of the allowable range in step S404, the ECU 15 returns to step S402 and increases the duty frequency. That is, the ECU 15 increases the duty frequency until the duty frequency reaches the upper limit of the allowable range when the sliding failure of the intake amount control valve 30 is not eliminated.

  On the other hand, when it is determined in step S404 that the duty frequency is equal to or higher than the upper limit of the allowable range, the ECU 15 decreases the duty frequency (S405). When the duty frequency is decreased in step S405, the ECU 15 determines again whether or not the sliding amount of the suction amount control valve 30 has been eliminated (S406). If the ECU 15 determines in step S406 that the sliding failure of the intake amount control valve 30 has been resolved, the ECU 15 repeats the process from the beginning. On the other hand, if the ECU 15 determines in step S406 that the sliding failure of the intake amount control valve 30 has not been eliminated, the ECU 15 determines whether the duty frequency is within an allowable range (S407).

When the duty frequency is larger than the lower limit of the allowable range in step S407, the ECU 15 returns to step S405 and decreases the duty frequency. That is, when the sliding failure of the intake amount control valve 30 is not eliminated, the ECU 15 decreases the duty frequency until the duty frequency reaches the lower limit of the allowable range.
When the ECU 15 determines in step S407 that the duty frequency is less than or equal to the lower limit of the allowable range, the ECU 15 determines that the sliding failure is not resolved and the supply pump 12 including the suction amount control valve 30 has failed (S408). And ECU15 memorize | stores failure determination (S409), and implements a fail safe treatment (S410).

  As described above, in the third embodiment of the sliding failure elimination control, when the control current output from the ECU 15 to the intake amount control valve 30 is feedback-controlled, the duty frequency is increased or decreased. As a result, sliding between the case 31 of the suction amount control valve 30 and the valve member 32 is promoted, and the sliding failure is eliminated. Therefore, it is possible to quickly eliminate the sliding failure before the influence such as the pressure drop of the fuel supplied to the injector 14 occurs.

(Sliding failure elimination judgment)
In the plurality of embodiments of the sliding failure elimination control described above, it is determined whether or not the sliding failure of the suction amount control valve 30 has been eliminated at a predetermined timing of the flow. Specifically, in the case of the first embodiment shown in FIG. 4, it is determined in step S203 and step S206 whether or not the sliding failure of the intake amount control valve 30 has been resolved. In the case of the second embodiment shown in FIG. 6, in step S303 and step S306, in the case of the third embodiment shown in FIG. 9, in step S403 and step S406, whether the sliding failure of the intake amount control valve has been eliminated. It is determined whether or not. The determination of whether or not the sliding failure of the suction amount control valve 30 has been resolved is performed when at least one of the sliding failure detection shown in FIG. 3 or the sliding failure elimination determination shown in FIG. 10 is established. You may comprise so that it may determine.

Therefore, here, the sliding failure elimination determination will be described based on FIG. The sliding failure elimination determination shown in FIG. 10 is carried out by substantially the same procedure as the sliding failure detection shown in FIG. Therefore, here, the difference from the sliding failure detection will be mainly described, and the description of the common points will be omitted.
When the determination to eliminate the sliding failure is started, the ECU 15 sets the initial value to 0 (S501). The initial values set by the ECU 15 are the large deviation determination count N and the determination time interval DT. That is, the ECU 15 sets N = 0 and DT = 0.

  When the ECU 15 sets an initial value in step S501, the ECU 15 increments the determination time interval DT by one and sets DT = DT + 1 (S502). Thus, every time the determination of the sliding failure elimination shown in FIG. 10 is performed, the count of the determination time interval DT is advanced by “1”.

  When the ECU 15 proceeds to count the determination time interval DT in step S502, the ECU 15 determines the operating condition of the diesel engine (S503). For example, the ECU 15 determines whether the diesel engine is in a stable operating state from the rotational speed Ne of the diesel engine detected by the rotational speed sensor, the fuel injection amount Qf, and the accelerator pedal depression amount Ac.

When the ECU 15 determines in step S503 that the diesel engine is in a stable operating state, the ECU 15 performs a target rail pressure condition determination (S504). The ECU 15 determines whether the absolute value of the difference between the currently set target rail pressure Pf (i) and the target rail pressure Pf (i−1) set in the previous flow is greater than a predetermined value Pfd. Calculate whether or not. When the absolute value of the difference between the target rail pressures is larger than the predetermined value Pfd, the ECU 15 determines that the target rail pressure is suitable for determining the elimination of the sliding failure. On the other hand, when the absolute value of the difference between the target rail pressures is equal to or less than the predetermined value Pfd, the ECU 15 determines that the target rail pressure is not suitable for determining the elimination of the sliding failure, and returns to step S502.
When the ECU 15 determines that the variation in the target rail pressure is appropriate in step S504, the ECU 15 performs a small deviation determination from the actual rail pressure and the target rail pressure (S505). The ECU 15 determines that the deviation between the actual rail pressure and the target rail pressure is small when the absolute value of the difference between the actual rail pressure NPc (i) and the target rail pressure Pf (i) is smaller than a predetermined value Pcd.

  3, when the deviation between the actual rail pressure of the common rail 13 and the target rail pressure is large, the ECU 15 detects a sliding failure occurring in the intake amount control valve 30. On the other hand, in the case of the determination of the elimination of the sliding failure shown in FIG. 10, the ECU 15 detects whether or not the sliding failure occurring in the intake amount control valve 30 has been eliminated. When the sliding failure of the intake amount control valve 30 is eliminated, the control accuracy of the flow rate of fuel supplied from the intake amount control valve 30 to the supply pump 12 and the flow rate of fuel supplied from the supply pump 12 to the common rail 13 are improved. . Therefore, the actual rail pressure of the common rail 13 approximates the target rail pressure, and the deviation between the actual rail pressure and the target rail pressure becomes small. Therefore, the ECU 15 determines that the deviation is small when the deviation between the actual rail pressure NPc (i) and the target rail pressure Pf (i) is smaller than Pcd. The deviation Pcd set here may be the same value as in the case of the sliding failure detection shown in FIG. 3, or may be a different value.

If the ECU 15 determines in step S505 that the deviation between the actual rail pressure NPc (i) and the target rail pressure Pf (i) is smaller than Pcd, the ECU 15 advances the count of the small deviation determination count N by one (S506). On the other hand, if ECU15 determines with the deviation calculated in step S505 being more than Pcd, it will return to step S502.
When the count of the small deviation determination count N is incremented by one in step S506, the ECU 15 determines whether or not the counted small deviation determination count N is greater than a predetermined value N2 (S507). The ECU 15 returns to step S502 when the small deviation determination count N is equal to or smaller than the predetermined value N2 in step S507. Here, the set predetermined value N2 may be the same as or different from the predetermined value N1 set in the sliding failure detection shown in FIG.

  If the ECU 15 determines in step S507 that the small deviation determination count N is greater than N2, the ECU 15 determines whether the determination time interval DT is longer than the predetermined value DT2 (S508). The period in which the deviation between the actual rail pressure and the target rail pressure is reduced by eliminating the sliding failure continues. That is, when the sliding failure is eliminated, the phenomenon that the deviation between the actual rail pressure and the target rail pressure is reduced continues. Therefore, when the determination time interval DT is longer than the predetermined value DT2 in step S508, the ECU 15 determines that the sliding failure of the intake amount control valve 30 has been eliminated (S509). On the other hand, the ECU 15 returns to step S501 when the determination time interval DT is equal to or less than the predetermined value DT2. Here, the predetermined value DT2 of the determination time interval may be the same as or different from the predetermined value DT1 of the sliding failure detection shown in FIG.

By the above procedure, it is determined whether or not the sliding failure that occurs between the valve member 32 of the suction amount control valve 30 and the case 31 has been resolved.
As described above, in the fuel injection device 10 according to the embodiment of the present application, whether or not there is a sliding failure between the case 31 and the valve member 32 of the intake amount control valve 30 based on the actual rail pressure of the common rail 13 and the target rail pressure. Is detected. When a sliding failure is detected, the ECU 15 changes the control current output to the suction amount control valve 30 to perform control for eliminating the sliding failure. Each time the ECU 15 performs control for eliminating the sliding failure, the ECU 15 determines whether or not the sliding failure has been resolved, and continues or terminates the control for eliminating the sliding failure. Accordingly, it is possible to detect an abnormality in the supply pump 12 including the intake amount control valve 30 at an early stage, and when an abnormality is detected, the actual rail pressure of the fuel stored in the common rail 13 changes and the injector 14 changes. The sliding failure can be eliminated before the injected fuel is affected.

In the case of the intake amount control valve 30 of the fuel injection device 10 according to the embodiment of the present invention described above, the fuel in the fuel tank 11 flows into the fuel passage 34 of the valve member 32, and the port 35, the fuel groove 36 and the opening 33. The example of flowing out to the supply pump 12 via the above has been described. However, contrary to the embodiment, the flow of the fuel flows into the fuel passage 34 from the opening 33 via the fuel groove 36 and the port 35, and flows out from the end of the valve member 32 to the supply pump 12. It is good.
The present invention described above is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof.

Schematic which shows the structure of the fuel-injection apparatus by one Embodiment of this invention. Sectional drawing which shows the outline of the intake amount control valve of the fuel-injection apparatus by one Embodiment of this invention. Schematic showing a flow of sliding failure detection in a fuel injection device according to an embodiment of the present invention. Schematic which shows the flow of 1st Embodiment of the sliding failure elimination in the fuel-injection apparatus by one Embodiment of this invention. The block diagram which shows the outline of the feedback control in the fuel-injection apparatus by one Embodiment of this invention. Schematic which shows the flow of 2nd Embodiment of sliding failure elimination in the fuel-injection apparatus by one Embodiment of this invention. Schematic showing generation of control current pulses in a fuel injection device according to an embodiment of the present invention. It is a schematic diagram which shows the pulse of control current, (A) shows before duty assist, (B) shows after duty assist. Schematic which shows the flow of 3rd Embodiment of the sliding defect elimination in the fuel-injection apparatus by one Embodiment of this invention. Schematic which shows the flow of a sliding failure elimination detection in the fuel-injection apparatus by one Embodiment of this invention.

Explanation of symbols

  In the drawings, 10 is a fuel injection device, 11 is a fuel tank, 12 is a supply pump, 13 is a common rail, 15 is an ECU (sliding state detection means, defect elimination control means, pressure setting means, pressure detection means), and 24 is pressure. Sensor (pressure detection means), 30 is an intake amount control valve, 31 is a case, 32 is a valve member, 33 is an opening (first opening), 35 is a port (second opening), and 36 is a fuel groove (first 2 openings).

Claims (5)

A supply pump that pressurizes the fuel drawn from the fuel tank and supplies it to the common rail;
A cylindrical case provided on the fuel tank side of the supply pump and provided with a first opening passing through the side wall, and a second opening provided through the side wall provided in the axial direction on the inner peripheral side of the case A suction valve for controlling the amount of fuel sucked from the fuel tank into the supply pump by an area where the first opening and the second opening overlap, and having a sliding cylindrical valve member; A fuel injection device for an internal combustion engine comprising:
Sliding state detecting means for detecting a sliding state between the case and the valve member of the intake amount control valve;
When the sliding state detection means detects a failure in the sliding state between the case and the valve member, a failure elimination control means that performs control to eliminate the sliding state failure between the case and the valve member. and, with a,
The sliding state detection means includes pressure setting means for setting the fuel pressure in the common rail as a target pressure, and pressure detection means for detecting the fuel pressure in the common rail as an actual pressure,
The sliding state detecting means has a poor sliding state between the case and the valve member when the difference between the target pressure and the actual pressure is a predetermined value or more within a predetermined period. And determine that
The defect elimination control means includes
Change the control for the intake amount control valve to the upper limit of a preset allowable range to the side where at least one of the moving amount or moving force of the valve member increases,
When it is determined that the sliding failure has not been resolved even if the control for the intake amount control valve is changed to the upper limit of the allowable range to the side where at least one of the movement amount or the moving force of the valve member increases, The fuel injection device for an internal combustion engine, wherein the control for the intake amount control valve is changed to a lower limit of a preset allowable range so that at least one of the movement amount and the movement force of the valve member decreases . 2. The fuel for an internal combustion engine according to claim 1, wherein the defect elimination control unit changes a control gain for the intake amount control valve to change at least one of a movement amount and a movement force of the valve member. Injection device. The defect elimination control means changes at least one of a movement amount and a movement force of the valve member by changing an ON period in at least a transition period of a pulsed control signal for the suction amount control valve. The fuel injection device for an internal combustion engine according to claim 1. 4. The fuel injection device for an internal combustion engine according to claim 3, wherein the defect elimination control means changes the assist amount during the ON period. 4. The fuel injection device for an internal combustion engine according to claim 3, wherein the defect elimination control means changes the frequency of the on period.

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