JP2008038895A - Controller for fuel pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a fuel pump detecting a malfunction of the fuel pump at an early stage, carrying out restoration from the malfunction, and reducing change of an operating state. <P>SOLUTION: A rotational frequency of a brushless motor 32 is dependent on a voltage of a battery 14. Accordingly, in an ECU 20, a malfunction of the fuel pump 30 is detected from the voltage of the battery 14 and the rotational frequency of the brushless motor 32. In the ECU 20, when a malfunction of the fuel pump 30 is detected, the fuel pump 30 is temporarily stopped, and then, restarted. By this, a malfunction of the fuel pump 30 is resolved such as erroneous stopping in the brushless motor 32 of the fuel pump 30, or biting in a pump part 31, and a normal operating state is restored. In the ECU 20, when the fuel pump 30 is stopped, change of the operating state of an engine 60 is reduced by increasing an injection amount of fuel to the engine 60, or advancing ignition timing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control device for a fuel pump that supplies fuel from a fuel tank to an internal combustion engine, and more particularly to a control device for a fuel pump that is driven by a brushless motor.

  In recent years, in order to achieve miniaturization and power saving, application of a brushless motor instead of a conventional brush motor has been proposed as a drive source of a fuel pump (for example, Patent Document 1, Patent Document 1 regarding a fuel pump to which a brushless motor is applied). For a control method of the brushless motor, see Patent Document 2). Such a brushless motor of the fuel pump is directly driven by the voltage of the power source in order to simplify the circuit configuration. Therefore, for example, when mounted on a vehicle, the rotational speed of the brushless motor of the fuel pump depends on the voltage of the battery as the power source. That is, the rotation speed of the brushless motor that determines the amount of fuel discharged by the fuel pump varies depending on the battery voltage.

  However, in the case of a fuel pump driven by a brushless motor, the brushless motor is directly driven by the voltage of the power source. For this reason, even if the flow rate of the fuel discharged from the fuel pump changes, it cannot be determined whether the change is due to a change in the voltage of the power supply or an abnormality in the fuel pump. As a result, there is a problem that it is difficult to detect abnormality of the fuel pump.

Japanese Patent Laid-Open No. 03-284187 JP 08-317686 A

Accordingly, an object of the present invention is to provide a fuel pump control device that detects an abnormality of a fuel pump at an early stage.
Another object of the present invention is to provide a control device for a fuel pump that, when an abnormality of the fuel pump is detected, restores the fuel pump to a normal state.
Another object of the present invention is to provide a fuel pump control device that ensures stable operation of an internal combustion engine even when the amount of fuel supply changes due to abnormality of the fuel pump.

  In the invention according to any one of claims 1 to 3, the voltage of the power source and the rotation speed of the brushless motor are detected. The abnormality determining means determines whether or not the detected voltage of the power source and the rotation speed of the brushless motor are within a predetermined range of the relationship between the voltage and the rotation speed stored in advance in the storage means. Then, the abnormality detection means determines that an abnormality has occurred in the fuel pump when the relationship is outside the predetermined range. For example, when the number of rotations of the brushless motor is higher than the upper limit with respect to a certain power supply voltage, the brushless motor is idling due to a step-out or the like, and it is considered that the amount of fuel discharged from the fuel pump is abnormal. Also, for example, when the rotational speed of the brushless motor is less than the lower limit with respect to a certain power supply voltage, the rotation of the fuel pump driven by the brushless motor or the brushless motor is restricted due to foreign object biting, etc., and the fuel pump discharges fuel. It is thought that the amount is abnormal. As described above, the abnormality detection means detects the abnormality of the fuel pump from the power supply voltage and the rotation speed of the brushless motor. Therefore, the abnormality of the brushless motor and the fuel pump can be detected at an early stage.

  According to the second aspect of the present invention, when the abnormality detecting means detects an abnormality of the fuel pump, the restarting means once stops and restarts the brushless motor. For example, when the brushless motor is idling due to step-out, the brushless motor is stopped and restarted to return to the normal rotation state. In addition, when the rotation of the brushless motor is restricted by foreign object biting or the like, the brushless motor is stopped and then restarted to release the foreign object bite and return to a normal rotation state. In this way, the restarting means stabilizes the rotational state of the brushless motor by temporarily stopping the brushless motor and then restarting it. Therefore, even if an abnormality of the fuel pump is detected, the fuel pump can be returned to a normal operating state.

  According to a third aspect of the present invention, the characteristic adjusting means adjusts the characteristic of the internal combustion engine when an abnormality is detected in the fuel pump and the fuel pump is stopped. If the fuel pump is stopped when the fuel pump is restarted, the amount of fuel discharged from the fuel pump decreases. Thus, once an abnormality is detected in the fuel pump and once stopped, the flow rate of the fuel supplied to the internal combustion engine changes. For this reason, the operating state of the internal combustion engine may change, and the behavior of the vehicle equipped with the internal combustion engine may become unstable. Therefore, the characteristic adjusting means adjusts the amount of fuel injected into the internal combustion engine, the ignition timing, or the like to minimize the change in the operating state of the internal combustion engine. Therefore, it is possible to reduce a change in the operating state of the internal combustion engine and ensure a stable operating state.

According to the fourth aspect of the present invention, the voltage of the power source and the rotation speed of the brushless motor are detected. The abnormality determining means determines whether or not the detected voltage of the power source and the rotation speed of the brushless motor are within a predetermined range of the relationship between the voltage and the rotation speed stored in advance in the storage means. Then, the abnormality detection means determines that an abnormality has occurred in the fuel pump when the relationship is outside the predetermined range. For example, when the number of rotations of the brushless motor is higher than the upper limit with respect to a certain power supply voltage, the brushless motor is idling due to a step-out or the like, and it is considered that the amount of fuel discharged from the fuel pump is abnormal. Also, for example, when the rotational speed of the brushless motor is less than the lower limit with respect to a certain power supply voltage, the rotation of the fuel pump driven by the brushless motor or the brushless motor is restricted due to foreign object biting, etc., and the fuel pump discharges fuel. It is thought that the amount is abnormal. As described above, the abnormality detection means detects the abnormality of the fuel pump from the power supply voltage and the rotation speed of the brushless motor. Therefore, the abnormality of the brushless motor and the fuel pump can be detected at an early stage.
When the abnormality detecting means detects an abnormality of the fuel pump, the restarting means temporarily stops the brushless motor and then restarts it. The restarting means stabilizes the rotational state of the brushless motor by stopping the brushless motor and then restarting it. Therefore, even if an abnormality of the fuel pump is detected, the fuel pump can be returned to a normal operating state.

  In the invention according to claim 5, the voltage of the power source and the rotation speed of the brushless motor are detected. The abnormality determining means determines whether or not the detected voltage of the power source and the rotation speed of the brushless motor are within a predetermined range of the relationship between the voltage and the rotation speed stored in advance in the storage means. Then, the abnormality detection means determines that an abnormality has occurred in the fuel pump when the relationship is outside the predetermined range. For example, when the number of rotations of the brushless motor is higher than the upper limit with respect to a certain power supply voltage, the brushless motor is idling due to a step-out or the like, and it is considered that the amount of fuel discharged from the fuel pump is abnormal. Also, for example, when the rotational speed of the brushless motor is less than the lower limit with respect to a certain power supply voltage, the rotation of the fuel pump driven by the brushless motor or the brushless motor is restricted due to foreign object biting, etc., and the fuel pump discharges fuel. It is thought that the amount is abnormal. As described above, the abnormality detection means detects the abnormality of the fuel pump from the power supply voltage and the rotation speed of the brushless motor. Therefore, the abnormality of the brushless motor and the fuel pump can be detected at an early stage.

  The characteristic adjusting means adjusts the characteristic of the internal combustion engine when the fuel pump returns from the abnormality. When an abnormality occurs in the fuel pump and the fuel pump is temporarily stopped, the amount of fuel discharged from the fuel pump decreases. Thus, when an abnormality is detected in the fuel pump and the fuel pump is stopped, the flow rate of the fuel supplied to the internal combustion engine changes. For this reason, the operating state of the internal combustion engine may change, and the behavior of the vehicle equipped with the internal combustion engine may become unstable. Therefore, the characteristic adjusting means adjusts the amount of fuel injected into the internal combustion engine, the ignition timing, or the like to minimize the change in the operating state of the internal combustion engine. Therefore, it is possible to reduce a change in the operating state of the internal combustion engine and ensure a stable operating state.

  According to the sixth aspect of the present invention, the voltage of the power source and the rotation speed of the brushless motor are detected. The abnormality determining means determines whether or not the detected voltage of the power source and the rotation speed of the brushless motor are within a predetermined range of the relationship between the voltage and the rotation speed stored in advance in the storage means. Then, the abnormality detection means determines that an abnormality has occurred in the fuel pump when the relationship is outside the predetermined range. For example, when the number of rotations of the brushless motor is higher than the upper limit with respect to a certain power supply voltage, the brushless motor is idling due to a step-out or the like, and it is considered that the amount of fuel discharged from the fuel pump is abnormal. Also, for example, when the rotational speed of the brushless motor is less than the lower limit with respect to a certain power supply voltage, the rotation of the fuel pump driven by the brushless motor or the brushless motor is restricted due to foreign object biting, etc., and the fuel pump discharges fuel. It is thought that the amount is abnormal. As described above, the abnormality detection means detects the abnormality of the fuel pump from the power supply voltage and the rotation speed of the brushless motor. Therefore, the abnormality of the brushless motor and the fuel pump can be detected at an early stage.

When the abnormality detecting means detects an abnormality of the fuel pump, the restarting means temporarily stops the brushless motor and then restarts it. The restarting unit stabilizes the rotation state of the brushless motor by temporarily stopping the brushless motor and then restarting the restarting unit. Therefore, even if an abnormality of the fuel pump is detected, the fuel pump can be returned to a normal operating state.
Further, the characteristic adjusting means adjusts the characteristic of the internal combustion engine when the brushless motor is once stopped and then restarted. When an abnormality occurs in the fuel pump and the fuel pump is stopped, the amount of fuel discharged from the fuel pump decreases. Therefore, the operating state of the internal combustion engine changes due to the change in the flow rate of the fuel, and the behavior of the vehicle equipped with the internal combustion engine may become unstable. Therefore, the characteristic adjusting means adjusts the amount of fuel injected into the internal combustion engine, the ignition timing, or the like to minimize the change in the operating state of the internal combustion engine. Therefore, it is possible to reduce a change in the operating state of the internal combustion engine and ensure a stable operating state.

  According to the seventh aspect of the invention, when the brushless motor is stopped, the characteristic adjusting means extends the fuel injection period. When the brushless motor is stopped, the fuel discharge from the fuel pump stops. For this reason, the pressure of the fuel discharged from the fuel pump decreases. Therefore, the characteristic adjusting means ensures a sufficient fuel injection amount for continuing the operation of the internal combustion engine by extending the fuel injection period. Thereby, even if a fuel pump stops, the change of the operating state of an internal combustion engine is reduced. Therefore, a stable operating state of the internal combustion engine can be ensured.

  According to the eighth aspect of the invention, the characteristic adjusting means gradually extends the fuel injection period as the stop period of the brushless motor becomes longer. Each time fuel injection is performed after the brushless motor is stopped, the pressure of the fuel discharged from the fuel pump gradually decreases. For this reason, the characteristic adjusting means gradually extends the fuel injection period in accordance with the gradually decreasing fuel pressure. Thereby, even if the fuel pump is stopped, a sufficient fuel injection amount is secured to continue the operation of the internal combustion engine. Therefore, a stable operating state of the internal combustion engine can be ensured.

  According to the ninth aspect of the present invention, when the brushless motor is stopped, the characteristic adjusting means increases the fuel injection amount. When the brushless motor is stopped, the fuel discharge from the fuel pump stops. For this reason, the pressure of the fuel discharged from the fuel pump decreases. Therefore, the characteristic adjusting means secures sufficient fuel to continue the operation of the internal combustion engine by increasing, or enriching, the fuel injection amount. Thereby, even if a fuel pump stops, the change of the operating state of an internal combustion engine is reduced. Therefore, a stable operating state of the internal combustion engine can be ensured.

  In the invention described in claim 10, the characteristic adjusting means gradually extends the fuel injection amount as the stop period of the brushless motor becomes longer. Each time fuel injection is performed after the brushless motor is stopped, the pressure of the fuel discharged from the fuel pump gradually decreases. Therefore, the characteristic adjusting means gradually increases, that is, enriches the fuel injection amount in accordance with the gradually decreasing fuel pressure. As a result, even when the fuel pump is stopped, sufficient fuel injection is ensured to continue the operation of the internal combustion engine. Therefore, a stable operating state of the internal combustion engine can be ensured.

  In the invention described in claim 11, when the brushless motor is stopped, the characteristic adjusting means corrects the ignition timing of the internal combustion engine to the advance side. When the brushless motor is stopped, the fuel discharge from the fuel pump stops. For this reason, the pressure of the fuel discharged from the fuel pump decreases. Therefore, the characteristic adjusting means reduces the fluctuation of the output torque of the internal combustion engine by correcting the ignition timing of the air-fuel mixture in the internal combustion engine to the advance side. Thereby, even if a fuel pump stops, the change of the operating state of an internal combustion engine is reduced. Therefore, a stable operating state of the internal combustion engine can be ensured.

  In the invention described in claim 12, as the stop period of the brushless motor becomes longer, the characteristic adjusting means gradually increases the correction amount of the ignition timing to the advance side. Each time fuel injection is performed after the brushless motor is stopped, the pressure of the fuel discharged from the fuel pump gradually decreases, and the fuel injection amount decreases. For this reason, the characteristic adjusting means gradually corrects the ignition timing to the advance side according to the gradually decreasing amount of fuel injection. Thereby, even if the stop of the fuel pump is continued, the fluctuation of the output torque of the internal combustion engine is reduced. Therefore, a stable operating state of the internal combustion engine can be ensured.

  In the invention according to claim 13 or 14, the voltage of the power source and the rotation speed of the brushless motor are detected. The abnormality determining means determines whether or not the detected voltage of the power source and the rotation speed of the brushless motor are within a predetermined range of the relationship between the voltage and the rotation speed stored in advance in the storage means. At this time, the abnormality determination means detects an abnormality of the fuel pump from the remaining amount of fuel in the fuel tank. For example, when it is determined from the number of rotations of the brushless motor for a certain power supply voltage that there is an abnormality in the fuel pump, it is determined whether the abnormality is due to the fuel pump or the lack of fuel in the fuel tank. I can't. That is, when the remaining amount of fuel in the fuel tank is small, that is, in a so-called out-of-gas condition, the fuel pump rotates idly, and the relationship between the voltage of the power source and the rotation speed of the brushless motor may be outside a predetermined range. Therefore, the abnormality determining means detects the abnormality of the fuel pump based on the remaining amount of fuel stored in the fuel tank when detecting the abnormality of the fuel pump. Therefore, it is possible to detect the abnormality of the brushless motor and the fuel pump at an early stage while reducing the influence of the remaining amount of fuel in the fuel tank.

  In the invention according to claim 15 or 16, the abnormality detection means determines whether or not the abnormality of the fuel pump occurs a plurality of times within the set period. When the gas runs out, the remaining amount of fuel in the fuel tank is reduced. Therefore, the abnormality detecting means intermittently detects the abnormality of the fuel pump according to the fuel level. On the other hand, when an abnormality has occurred in the brushless motor of the fuel pump, it is difficult for the brushless motor of the fuel pump to recover from an abnormal state to a normal state. For this reason, the abnormality detection means continuously detects abnormality of the fuel pump. Therefore, the abnormality detection means detects abnormality of the brushless motor and the fuel pump based on the abnormality frequency of the fuel pump. Therefore, the abnormality of the brushless motor and the fuel pump can be detected according to the remaining amount of fuel in the fuel tank.

  In the invention according to claim 17, when the abnormality detecting means determines that the gas is exhausted, the warning means issues a warning. The warning means warns by an arbitrary method such as a visual warning due to blinking of a lamp, an audible warning such as a buzzer sound, or a tactile warning due to vibration of a predetermined part. As a result, for example, it is possible to prompt the passenger of the vehicle to recognize the occurrence of the abnormality and to take a quick response.

  In the invention according to claim 18, when the abnormality detecting means determines that the gas is exhausted, the opening / closing means opens the connection passage connecting the reservoir tank and the main tank of the fuel pump. As a result, fuel is supplied from the reservoir tank in which fuel is stored separately from the main tank to the main tank. Therefore, the fuel pump can discharge fuel from the fuel tank to the outside.

  In the nineteenth aspect of the invention, when the abnormality detecting means detects an abnormality of the fuel pump, the restarting means once stops and restarts the brushless motor. For example, when the brushless motor is idling due to step-out, the brushless motor is stopped and restarted to return to the normal rotation state. In addition, when the rotation of the brushless motor is restricted by foreign object biting or the like, the brushless motor is stopped and then restarted to release the foreign object bite and return to a normal rotation state. In this way, the restarting means stabilizes the rotational state of the brushless motor by temporarily stopping the brushless motor and then restarting it. Therefore, even if an abnormality of the fuel pump is detected, the fuel pump can be returned to a normal operating state.

  In the twentieth aspect, the characteristic adjusting means adjusts the characteristic of the internal combustion engine when an abnormality is detected in the fuel pump and the fuel pump is stopped. If the fuel pump is stopped when the fuel pump is restarted, the amount of fuel discharged from the fuel pump decreases. Thus, once an abnormality is detected in the fuel pump and once stopped, the flow rate of the fuel supplied to the internal combustion engine changes. For this reason, the operating state of the internal combustion engine may change, and the behavior of the vehicle equipped with the internal combustion engine may become unstable. Therefore, the characteristic adjusting means adjusts the amount of fuel injected into the internal combustion engine, the ignition timing, or the like to minimize the change in the operating state of the internal combustion engine. Therefore, it is possible to reduce a change in the operating state of the internal combustion engine and ensure a stable operating state.

  According to a twenty-first aspect of the present invention, the correcting means corrects the relationship between the power supply voltage stored in the storage means and the rotational speed of the brushless motor in accordance with the characteristics of the fuel used. In recent years, an internal combustion engine using a biological fuel such as bioethanol has been proposed in consideration of the influence on the environment. On the other hand, these bio-derived fuels have a difference in properties such as viscosity from conventional petroleum-based fuels such as gasoline and light oil. Therefore, for example, even if the relationship between the voltage of the power source and the rotation speed of the brushless motor is set on the assumption that gasoline is used, the relationship varies depending on the proportion of ethanol mixed therein. Therefore, for example, the correction means estimates the ratio of bioethanol contained in the fuel from the voltage of a predetermined power source and the rotation speed of the brushless motor corresponding to this voltage, and stores the memory stored in the storage means from the estimated ratio. Correct the value. Therefore, the abnormality of the brushless motor and the fuel pump can be detected at an early stage regardless of the type of fuel.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.
(First Embodiment of Fuel Pump Control Device)
First, FIG. 1 shows a fuel pump control apparatus according to a first embodiment of the present invention. A fuel pump control device 10 shown in FIG. 1 includes a control unit 11 and a fuel pump 30. The fuel pump 30 is installed inside a fuel tank of a two-wheeled vehicle equipped with a gasoline engine having a displacement of about 150 cc as an internal combustion engine, for example. As shown in FIG. 2, the fuel pump 30 includes a pump unit 31 and a brushless motor 32 that drives the pump unit 31. The housing 33 forms a housing for both the pump unit 31 and the brushless motor 32. A pump case 34, a pump cover 35, and an end cover 36 are fixed to the housing 33.

  The pump unit 31 is a turbine pump having a pump case 34, a pump cover 35, and an impeller 37. The pump case 34 and the pump cover 35 accommodate an impeller 37 as a rotating member in a rotatable manner. A C-shaped pump passage 38 is formed in the circumferential direction of the fuel pump 30 between the pump case 34, the pump cover 35, and the impeller 37. The fuel sucked from the suction port 39 provided in the pump cover 35 is pressurized in the pump passage 38 by the rotation of the impeller 37. The pressurized fuel is pumped to the brushless motor 32 side and discharged from the discharge port 45 via the fuel passage 43 and the discharge passage 44 between the stator core 41 and the rotor 42.

  The brushless motor 32 is a sensorless drive brushless motor that does not have a brush and a commutator. The brushless motor 32 has a stator core 41 and a rotor 42. The stator core 41 has a plurality of cores 47 arranged in the circumferential direction and wound with a coil 46. By controlling the energization to the coil 46 according to the rotational position of the rotor 42, the magnetic poles formed on the inner peripheral surface of each core 47 facing the rotor 42 are switched. The rotor 42 has a shaft 48 and a permanent magnet 49. The rotor 42 is rotatably installed on the inner periphery of the stator core 41. Both end portions in the axial direction of the shaft 48 are supported by the bearing portion 51 and the bearing portion 52, respectively. The permanent magnets 49 are magnetized so as to form different magnetic poles alternately in the rotational direction on the outer peripheral surface facing the stator core 41.

  As shown in FIG. 1, the control unit 11 as a control device includes a control circuit unit 12 and an ECU 20. Note that the control circuit unit 12 may be configured as an electronic circuit integrated with the ECU 20. The control circuit unit 12 outputs a control signal to the brushless motor 32 of the fuel pump 30 to drive the brushless motor 32 to rotate. In the brushless motor 32, energization of the coil 46 is controlled by a control signal output from the control circuit unit 12. Thereby, the magnetic pole formed in the inner peripheral surface of each core 47 of the stator core 41 is switched, and the rotor 42 rotates. As the rotor 42 rotates, the impeller 37 rotates together with the shaft 48, and the fuel in the pump passage 38 is pressurized.

  The control circuit unit 12 includes a rotation speed detection unit 13 as a rotation speed detection unit that detects the rotation speed of the brushless motor 32. The rotation speed detection unit 13 detects the rotation speed of the brushless motor 32 by reading, for example, a control signal output from the control circuit unit 12. The rotation speed detection unit 13 outputs the detected rotation speed of the brushless motor 32 to the ECU 20 as an electric signal.

  The ECU 20 is constituted by a microcomputer having a CPU 21, a ROM 22 and a RAM 23. CPU21 controls the whole vehicle by which the engine 60 including the fuel pump 30 is mounted by the computer program currently recorded on ROM22, for example. The ECU 20 is electrically connected to the control circuit unit 12. The ECU 20 controls the brushless motor 32 via the control circuit unit 12. The ECU 20 also functions as an abnormality detecting means and a restarting means in the claims by operating in accordance with a computer program recorded in the ROM 22. Note that the ECU 20 is not limited to the ROM 22 and may be configured to record a computer program or predetermined data in a non-volatile memory such as an EEPROM or a recording medium such as a hard disk or a DVD.

  The ECU 20 is connected to the engine control unit 61 as well as the control circuit unit 21. The engine control unit 61 controls the engine 60 to which fuel is supplied by the fuel pump 30. In the present embodiment, the engine control unit 61 includes an injector control unit 62 and an ignition timing control unit 63. The engine control unit 61 may be configured as an electronic circuit integrated with the ECU 20. The ECU 20, the injector control unit 62 and the ignition timing control unit 63 that constitute the engine control unit 61 constitute characteristic adjustment means in the claims. The injector control unit 62 drives an injector 64 that injects fuel into the engine 60. The injector 64 is a solenoid valve, and opens and closes by a control signal output from the injector control unit 62. The amount of fuel injected from the injector 64 is adjusted by a control signal output from the injector control unit 62. The ignition timing control unit 63 drives an ignition device 65 that ignites the air-fuel mixture sucked into the engine 60. The ignition device 65 has an ignition plug, for example, and intermittently ignites the air-fuel mixture by a control signal output from the ignition timing control unit 63. Thereby, the ignition timing of the air-fuel mixture sucked into the engine 60 is adjusted by the control signal output from the ignition timing control unit 63.

  The ECU 20 is supplied with electric power from a battery 14 as a power source. The ECU 20 supplies the electric power supplied from the battery 14 to each part of the vehicle including the fuel pump 30. The ECU 20 has a voltage detection unit 24 as voltage detection means for detecting the voltage of the battery 14. Thereby, the ECU 20 detects the voltage of the battery 14 via the voltage detection unit 24.

  The rotational speed of the brushless motor 32 with respect to the voltage of the battery 14 is recorded as a map in the ROM 22 of the ECU 20. That is, the ROM 22 of the ECU 20 is a storage unit in the claims. The number of rotations of the brushless motor 32 changes as the voltage of the battery 14 changes as shown in FIG. The map recorded in the ROM 22 includes the reference rotational speed, upper limit value, and lower limit value of the brushless motor 32 with respect to the voltage of the battery 14.

(Fuel pump abnormality detection)
Next, the abnormality detection procedure of the fuel pump 30 by the control device 10 of the fuel pump 30 having the above configuration will be described.
1. First Embodiment of Abnormality Detection A first embodiment of abnormality detection will be described with reference to FIG.
The ECU 20 executes an abnormality determination routine for determining whether an abnormality of the fuel pump 30 has occurred at a predetermined time. The abnormality determination routine is included as one of routines for monitoring the entire vehicle by the ECU 20, for example, and is periodically performed after the engine 60 is started. When the process proceeds to the abnormality determination routine, the ECU 20 first detects the voltage B of the battery 14 (S101). The ECU 20 obtains the voltage B of the battery 14 from the voltage detection unit 24. The ECU 20 records the obtained voltage B of the battery 14 in the RAM 23. When detecting the voltage of the battery 14, the ECU 20 detects the rotational speed NP of the brushless motor 32 of the fuel pump 30 (S102). The ECU 20 obtains the rotational speed NP of the brushless motor 32 from the rotational speed detection unit 13 of the control circuit unit 12. The ECU 20 records the obtained rotational speed NP of the brushless motor 32 in the RAM 23.

  The ECU 20 calculates the reference rotational speed NP0 of the brushless motor 32 corresponding to the voltage B of the battery 14 obtained in step S101 and recorded in the RAM 23 from the map recorded in the ROM 22 (S103). The ECU 20 records the calculated reference rotational speed NP0 in the RAM 23. When the reference rotational speed NP0 is calculated, ECU 20 calculates upper limit value NP0 + α and lower limit value NP0-α according to the reference rotational speed NP0.

  When the upper limit value NP0 + α and the lower limit value NP0−α are calculated, the ECU 20 determines whether or not the rotational speed NP of the brushless motor 32 obtained in step S102 is within a predetermined range (S104). That is, the ECU 20 determines whether or not the detected rotation speed NP of the brushless motor 32 is between the calculated upper limit value NP0 + α and the lower limit value NP0−α. The brushless motor 32 and the fuel pump 30 including the brushless motor 32 have a distribution as shown in FIG. Therefore, the ECU 20 calculates an upper limit value and a lower limit value set in advance with reference to the reference rotational speed NP0, and determines whether or not the detected rotational speed NP of the brushless motor 32 is within a predetermined range.

If the ECU 20 determines that the detected rotational speed NP of the brushless motor 32 is greater than the upper limit value NP0 + α or less than the lower limit value NP0−α, the ECU 20 determines that an abnormality has occurred in the fuel pump 30 (S105). Then, the ECU 20 records the pump abnormality determination flag FFPF in the RAM 23 as FFPF = 1 (S106). On the other hand, when the ECU 20 determines that the detected rotational speed NP of the brushless motor 32 is between the upper limit value and the lower limit value, that is, in the normal range, the ECU 20 records the pump abnormality determination flag FFPF as FFPF = 0 in the RAM 23 (S107). .
The abnormality detection of the fuel pump 30 is completed by the above procedure.

2. Second Embodiment of Abnormality Detection A second embodiment of abnormality detection will be described with reference to FIG. Detailed description of the procedure substantially the same as that of the first embodiment of abnormality detection is omitted.
When the ECU 20 proceeds to the abnormality determination routine, it detects the voltage B of the battery 14 and records the detected voltage B of the battery 14 in the RAM 23 (S201). Further, the ECU 20 detects the rotational speed NP of the brushless motor 32 of the fuel pump 30 and records the detected rotational speed NP of the brushless motor 32 in the RAM 23 (S202). Further, the ECU 20 calculates the reference rotational speed NP0 of the brushless motor 32 corresponding to the voltage B from the voltage B of the battery 14 obtained in step S201 (S203). Then, the ECU 20 calculates the upper limit value NP0 + β including the individual difference of the fuel pump 30 and the lower limit value NP0−γ according to the calculated reference rotational speed NP0.

  When the upper limit value NP0 + β and the lower limit value NP0−γ are calculated, the ECU 20 determines whether or not the rotational speed NP of the brushless motor 32 obtained in step S202 is equal to or lower than the upper limit value NP0 + β (S204). When the rotational speed NP is greater than the upper limit value NP0 + β, the ECU 20 sets the step-out abnormality determination flag FFPF1 to FFPF1 = 1 (S205). When the rotational speed NP is larger than the upper limit value NP0 + β, the brushless motor 32 is considered to be in a state of being idled out of phase with the phase of the control signal output from the control circuit unit 12, that is, in a step-out state. That is, it is considered that the brushless motor 32 rotates at a rotational speed larger than the rotational speed determined with respect to the voltage B supplied from the battery 14 as a power source. Therefore, when the ECU 20 determines that the rotational speed NP is greater than the upper limit value NP0 + β, the ECU 20 determines that a step-out abnormality has occurred in the brushless motor 32 and records it in the RAM 23 as a step-out abnormality determination flag FFPF1 = 1.

  On the other hand, when it is determined in step S204 that the rotational speed NP is equal to or lower than the upper limit value NP0 + β, the ECU 20 determines whether the rotational speed NP is equal to or higher than the lower limit value NP0−γ (S206). When the rotational speed NP is smaller than the lower limit value NP0−γ, the ECU 20 sets the biting abnormality determination flag FFPF2 to FFPF2 = 1 (S207). When the rotational speed NP is smaller than the lower limit value NP0-γ, it is considered that the brushless motor 32 is in a state where the rotational speed is decreasing. That is, it is considered that the brushless motor 32 rotates at a rotation speed smaller than the rotation speed determined with respect to the voltage B supplied from the battery 14 as a power source. This occurs when a cause that hinders rotation acts on the fuel pump 30, for example, when a foreign object is caught in the rotating part of the pump unit 31 or the brushless motor 32. Therefore, if the ECU 20 determines that the rotational speed NP is smaller than the lower limit value NP0−γ, the ECU 20 determines that a biting abnormality has occurred in the brushless motor 32 or the fuel pump 30, and sets the biting abnormality determination flag FFPF2 = 1 in the RAM 23. Record.

When it is determined in step S206 that the rotational speed NP is equal to or greater than the lower limit value NP0-γ, the ECU 20 determines that no abnormality has occurred in the fuel pump 30. Therefore, the ECU 20 records both the step-out abnormality determination flag FFPF1 and the biting abnormality determination flag FFPF2 in the RAM 23 as FFPF1 = 0 and FFPF2 = 0 (S208).
The abnormality detection of the fuel pump 30 is terminated by the abnormality procedure. In the second embodiment of the abnormality detection, it is possible to determine not only whether the fuel pump 30 is abnormal or not, but also whether the cause of the abnormality is due to a step-out or a foreign object bite.

(Fuel pump abnormal recovery procedure)
Next, an abnormality recovery procedure for the fuel pump 30 in which an abnormality is detected by the above procedure will be described.
1. First Embodiment of Abnormal Recovery When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, the ECU 20 shifts to an abnormal recovery routine shown in FIG. 6 and returns the fuel pump 30 from an abnormal state to a normal state. .
The ECU 20 performs an abnormality detection routine of the fuel pump 30 according to the procedure shown in FIG. 4 and determines whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S301). When the pump abnormality determination flag FFPF is FFPF = 0, since no abnormality is detected in the fuel pump 30, the ECU 20 ends the abnormality detection routine.

  When the pump abnormality determination flag FFPF is FFPF = 1, the ECU 20 determines whether or not the value of the restart standby counter CFPRST is 100 (S302). The restart standby counter CFPRST counts to 100 when the abnormality of the fuel pump 30 is detected and the abnormality recovery routine is completed. In other words, the initial value of the restart standby counter CFPRST is 100. Therefore, CPPRST = 100 at the time when the routine proceeds to the abnormal recovery routine in step S301.

  When the restart standby counter CFPRST is 100, the ECU 20 sets the restart standby counter CPRRST to 0 (S303). That is, the ECU 20 determines that the pump abnormality return routine has been started. Then, when the pump abnormality return routine is started, the ECU 20 stops supplying power to the fuel pump 30, that is, the brushless motor 32 (S304). Further, when the supply of power to the fuel pump 30, that is, the brushless motor 32 is stopped, the ECU 20 advances the value of the restart standby counter CFPRST by one (S305).

  Then, the ECU 20 determines whether or not the restart waiting counter CFPRST is 100 (S306). When the restart waiting counter CFPRST is not 100, the process returns to step S302. When the process returns from step S306, the restart standby counter CFPRST is not 100, so the process proceeds from step S302 to step S307. In step S307, it is determined whether or not the restart waiting counter CFPRST is 50. When the restart standby counter CFPRST is not 50, the process proceeds to step S305, and the value of CFPRST is advanced by one. Thereby, ECU20 continues the state which stopped supply of the electric power to the brushless motor 32 until it becomes restart standby counter CFPRST = 50.

  On the other hand, when the restart standby counter CFPRST reaches 50, the supply of power to the fuel pump 30, that is, the brushless motor 32 is resumed (S308). Then, the process proceeds to step S305, and the value of CPPRST is advanced by one. As a result, the ECU 20 continues to supply power to the brushless motor 32. When the count of the restart standby counter CFPRST advanced in step S305 reaches 100, the ECU 20 determines that a sufficient time has elapsed since the brushless motor 32 was restarted. Therefore, the ECU 20 ends the abnormal return routine (S309).

  As described above, in the first embodiment of abnormal recovery, the fuel pump 30, that is, the brushless motor 32 is restarted after the operation of the fuel pump 30 is stopped for a certain period using the count of the restart standby counter. As a result, for example, the fuel pump 30 in which idling has occurred due to step-out is out of step-out and returns to a normal rotation state. Further, for example, when a foreign object is caught in the pump unit 31, the foreign object bite is eliminated by stopping the brushless motor 32. Therefore, the fuel pump 30 can be returned to a normal operation state by restarting the brushless motor 32.

2. Second Embodiment of Abnormal Recovery When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 5, the ECU 20 shifts to an abnormal recovery routine shown in FIG. 7 and returns the fuel pump 30 from an abnormal state to a normal state. .
When the abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 5, the ECU 20 proceeds to the abnormality recovery routine shown in FIG. 7, and sets the pump restart standby counter CFPRST to CFPRST = 100 (S401). Further, the ECU 20 sets the pump reverse rotation determination counter CNFPRV to CNFPRV = 0 (S402).

  When the setting of the pump restart standby counter CFPRST and the pump reverse rotation determination counter CNFPRV is completed, the ECU 20 detects the state of the step-out abnormality determination flag FFPF1 (S403). When the step-out abnormality determination flag FFPF1 recorded in the RAM 23 is FFPF1 = 1, the ECU 20 proceeds to a first return mode routine described later (S404). On the other hand, when the step-out abnormality determination flag FFPF1 is FFPF1 = 0, the ECU 20 determines that the abnormality occurring in the fuel pump 30 is not in the step-out state.

  Then, the ECU 20 detects the state of the biting abnormality determination flag FFPF2 (S405). When the biting abnormality determination flag FFPF2 recorded in the RAM 23 is FFPF2 = 1, the ECU 20 proceeds to a second return mode routine described later (S406). On the other hand, when the biting abnormality determination flag FFPF2 is FFPF2 = 0, the ECU 20 determines that there is no abnormality in the fuel pump and ends the abnormality return routine.

First Return Mode Routine When the step-out abnormality determination flag FFPF1 is determined to be FFPF1 = 1 in step S403 described above, the process proceeds to the first return mode routine shown in FIG. 8 in step S404.
The step-out return mode as the first return mode routine shown in FIG. 8 is substantially the same as the abnormal return mode shown in FIG.

The ECU 20 determines whether or not the value of the restart standby counter CFPRST is 100 (S501). The initial value of the restart standby counter CFPRST is 100. For this reason, CPPRST = 100 at the time of shifting to the first return mode routine.
When the restart standby counter CFPRST is 100, the ECU 20 sets the restart standby counter CPRRST to 0 (S502). Then, when the first return mode routine is started, the ECU 20 stops supplying power to the fuel pump 30 (S503). Further, when the supply of power to the fuel pump 30 is stopped, the ECU 20 advances the value of the restart standby counter CFPRST by one (S504).

  Then, the ECU 20 determines whether or not the restart waiting counter CFPRST is 100 (S505). When the restart standby counter CFPRST is not 100, the process returns to step S501. At this time, since the restart standby counter is not 100, the process proceeds from step S501 to step S506. In step S506, it is determined whether or not the restart standby counter CFPRST is 50. When the restart standby counter CFPRST is not 50, the process proceeds to step S504, and the value of CFPRST is advanced by one. Thereby, ECU20 continues the state which stopped supply of the electric power to the fuel pump 30 until the restart waiting counter becomes 50.

  On the other hand, when the restart standby counter CFPRST reaches 50, the supply of power to the fuel pump 30 is resumed (S507). Then, the process proceeds to step S504, and the value of CPRRST is advanced by one. As a result, the ECU 20 continues to supply power to the fuel pump 30. When the count of the restart standby counter CFPRST advanced in step S504 reaches 100, the ECU 20 determines that a sufficient time has elapsed since the fuel pump 30 was restarted. Therefore, the ECU 20 ends the first return mode routine (S508).

Second Return Mode Routine When the biting abnormality determination flag FFPF2 is determined to be FFPF2 = 1 in step S405 of FIG. 7 described above, the process proceeds to the second return mode routine shown in FIG. 9 in step S406.
The ECU 20 sets the biting prevention restart standby counter CFPRVSS to 100 (S601). Then, the ECU 20 detects whether or not CFPRVSS is 100 (S602). When shifting to the second return mode routine, CFPRVSS is set to 100 in step S601. Therefore, in step S602, it is determined that CFPRVSS = 100.

  If it is determined in step S602 that CFPRVSS = 100, the ECU 20 determines that the second return mode routine has started, and sets CFPRVSS to 0 (S603). Then, the ECU 20 stops supplying power to the brushless motor 32, that is, the fuel pump 30 (S604). Further, the ECU 20 sets a pump reverse rotation start counter CFPRVSE to 100 (S605).

  When the setting of CFPRVSE is completed, the ECU 20 determines whether or not CFPRVSE = 0 (S606). CFPRVSE is set to 100 in step S605. Therefore, the ECU 20 returns to step S602 until CFPRVSE becomes zero. Since CFPRVSS = 0 is set in step S603, CFPRVSS is not 100 when returning to step S602. As a result, the ECU 20 proceeds to step S611 and determines whether or not CFPRVSS = 50 (S611). When CFPRVSS is not 50, the value of CFPRVSS is advanced by 1 (S612). Then, the ECU 20 repeatedly executes steps S602, S611, and S606 until CFPRVSS = 50.

  CFPRVSS indicates a period in which the supply of power to the fuel pump 30 is stopped. Therefore, if it is determined in step S611 that CFPRVSS = 50, it can be considered that the fuel pump 30 has a sufficient stop period. Therefore, the ECU 20 performs restart of the fuel pump 30. Here, the ECU 20 determines whether or not the value of the pump reverse rotation determination counter CNFPRV is an even number. CNFPRV is set to 0 in step S402 in FIG. Therefore, in step S613 in FIG. 9, it is determined that CNFPRV = even.

  If it is determined in step S613 that CNFPRV = even, the ECU 20 drives the fuel pump 30 in the reverse direction (S614). That is, the ECU 20 drives the fuel pump 30 in the direction opposite to the normal rotation direction that rotates when the fuel pump 30 discharges the fuel to the engine 60 side. When the ECU 20 is driven in the reverse rotation direction of the fuel pump 30, the ECU 20 sets a pump reverse rotation start counter CFPRVSE to 0 (S615).

  Since CFPRVSE is set to 0 in step S615, the ECU 20 determines that CFPRVSE = 0 in step S606. Further, the ECU 20 proceeds to step S621 and determines that CFPRVSE = 50 is not satisfied. Thereby, the ECU 20 advances the count of CFPRVSE by one (S622). Then, the ECU 20 determines whether or not CFPRVSE is 50 or more (S624). Thus, the ECU repeats steps S621 and S622 until CFPRVSE = 50. CFPRVSE indicates an elapsed period after the fuel pump 30 is driven in the reverse direction in step S614. Therefore, the ECU 20 determines that the drive period of the fuel pump 30 is insufficient until CFPRVSE = 50.

  On the other hand, when the ECU 20 determines that CFPRVSE = 50 in step S624, the process returns to step S621 and proceeds to step S623. That is, the ECU 20 determines that the drive period of the fuel pump 30 is sufficiently secured. Then, the ECU 20 advances the value of the pump reverse rotation determination counter CNFPRV by one (S623).

  If it is determined in step S624 that CFPRVSE is 50 or more, ECU 20 determines whether CNFPRV that has continued to be counted is 5 or more (S625). When CNFPRV is smaller than 5, the process returns to step S601. As a result, in step S604, the fuel pump 30 is stopped. Then, after a predetermined period has elapsed, that is, when CFPRVSS reaches 50, the process proceeds to step S613. Here, since the count of CNFPRV is advanced by one in step S623, CNFPRV is an odd number. Therefore, the fuel pump 30 is driven in the forward rotation direction (S616).

By the above procedure, the ECU 20 repeatedly executes the stop, reverse rotation, stop, and forward rotation of the fuel pump 30 until CNFPRV becomes 5 or more. When CNFPRV becomes 5 or more, the ECU 20 ends the second return mode routine (S626).
In the second return mode routine, the ECU 20 repeatedly performs stop, reverse rotation, stop, and forward rotation of the fuel pump 30. Thereby, when the rotation defect by the foreign material biting has arisen in the pump part 31 or the brushless motor 32, a foreign material is removed by repetition of forward rotation and reverse rotation. Therefore, even if an abnormality occurs in the fuel pump 30, the cause can be removed and a reliable operation of the fuel pump 30 can be ensured.

(Ensuring safety when the fuel pump is abnormal)
1. First Embodiment for Ensuring Safety When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, the ECU 20 shifts to the abnormality return routine shown in FIG. 6 and returns the fuel pump 30 to a normal state. At this time, as shown in FIG. 6, the fuel pump 30 is stopped for a certain period. Therefore, the pressure of the fuel supplied from the fuel pump 30 to the engine 60 decreases. Therefore, in the first embodiment for ensuring safety, when an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4 and the fuel pump 30 is stopped, the fuel injection amount from the injector 64 is reduced by the flow shown in FIG. Correction is performed to ensure stable operation of the engine 60.

  The ECU 20 determines whether or not it is the TAU calculation timing regardless of whether the fuel pump 30 is abnormal (S701). TAU is the fuel injection period from the injector 64. The ECU 20 calculates the fuel injection amount when it is time to inject fuel from the injector 64 in the engine control basic routine. If the pressure of the fuel supplied from the fuel pump 30 is constant, the amount of fuel injected from the injector 64 correlates with the valve opening time of the injector 64, that is, the injection time. Therefore, the ECU 20 shifts to TAU calculation when the fuel injection timing from the injector 64 comes.

  The ECU 20 calculates the rotational speed NE of the engine 60 in order to calculate TAU (S702). The engine 60 is provided with a rotational speed sensor 66 as shown in FIG. The ECU 20 calculates the rotational speed of the engine 60 from the electrical signal output from the rotational speed sensor 66. Further, the ECU 20 calculates the load P of the engine 60 (S703). The ECU 20 detects the pressure in an intake passage (not shown) through which intake air taken into the engine 60 flows. A pressure sensor 67 is installed in the intake passage, and the pressure sensor 67 outputs the detected pressure to the ECU 20 as an electrical signal. The ECU 20 calculates the load P of the engine 60 from the detected pressure in the intake passage.

  Further, the ECU 20 detects the state of the engine 60 (S704). Here, the ECU 20 detects various parameters such as the temperature THA of the intake air flowing through the intake passage, the temperature THW of the cooling water for cooling the engine 60, and the atmospheric pressure PA from various sensors (not shown). Thereby, ECU20 detects the state of the engine 60 used as the basis of calculation of TAU.

  When the ECU 20 calculates the rotational speed NE of the engine 60 and the load P of the engine 60 and detects the state of the engine 60, the ECU 20 determines whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S705). As described above, when abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.

  When FFPF = 1, the ECU 20 sets the square root of the reference fuel pressure PF0 as the fuel pressure correction coefficient FPF (S706). The fuel pressure correction coefficient FPF is a coefficient that corrects the fuel discharge pressure that decreases when the fuel pump 30 is stopped due to the detection of an abnormality. The reference fuel pressure PF0 is the pressure of the fuel discharged from the fuel pump 30. On the other hand, when FFPF = 0 where no abnormality of the fuel pump 30 is detected, the ECU sets FPF = 1.0 (S707). That is, the FPF is not corrected.

  When the fuel pressure correction coefficient FPF is set, the ECU 20 calculates TAU according to the following equation 1 (S708). The ECU 20 corrects the reference injection pulse width TP with the FPF calculated in step S707 and various parameters. The reference injection pulse width TP is obtained from the rotational speed NE of the engine 60 calculated in step S702 and the load P of the engine 60 calculated in step S703. The ECU 20 has, for example, a map of TP as a function of the rotational speed NE and the load P in the ROM 22. Therefore, the ECU 20 reads TP from the ROM 22 based on the calculated NE and P. The various parameters for correcting TP are, for example, the intake air temperature THA, the coolant temperature THW, the atmospheric pressure PA, etc. detected in step S704. The ECU 20 corrects the set TP with the FPF and various parameters, and adds the injector invalid injection time TV. The injector invalid injection time TV means a time during which fuel is not injected even if a control signal for commanding the valve opening to the injector 64 is output from the ECU 20 due to, for example, a delay in valve opening of the injector 64. Therefore, the ECU 20 calculates TAU according to the following formula 1.

TAU = TP × f (THA, THW, PA,...) × FPF + TV Equation 1
When the TAU is calculated, the ECU 20 outputs a control signal to the injector 64 based on the calculated TAU. Thus, fuel is injected from the injector 64 in accordance with the TAU output from the ECU 20 (S709).

  In the first embodiment for ensuring safety, when the fuel pump 30 stops and the pressure of the fuel discharged from the fuel pump 30 decreases, the injection period for injecting fuel from the injector 64 is extended. Thereby, even if the pressure of the fuel discharged from the fuel pump 30 decreases, the total amount of fuel injected from the injector 64 does not change greatly. As a result, even when the fuel pump 30 is stopped by detecting an abnormality in the fuel pump 30, a predetermined amount of fuel is injected into the engine 60. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

  In the first embodiment for ensuring safety described above, the example in which the FPF is calculated from the square root of PF0 in step S706 has been described. However, the FPF may be recorded in the ROM 22 as a coefficient that varies depending on the load P of the engine 60, for example. In order to increase the accuracy of the FPF, the FPF may be recorded in the ROM 22 as a coefficient that varies depending on both the load P of the engine 60 and the rotational speed NE of the engine 60. Further, the FPF may be calculated based on the load P of the engine 60 detected in step S703 as a function of the load P of the engine 60.

2. Second Embodiment for Ensuring Safety As described in the first embodiment for ensuring safety, when an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. The pressure of the fuel supplied to the engine 60 decreases. Therefore, the amount of fuel injected from the injector 64 is reduced, and the output torque of the engine 60 is reduced. Therefore, in the second embodiment for ensuring safety, when an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4 and the fuel pump 30 is stopped, the ignition timing of the engine 60 is advanced by the flow shown in FIG. To stabilize the output torque of the engine 60. The second embodiment for ensuring safety may be implemented together with the first embodiment for ensuring safety, or may be performed alone.

The ECU 20 determines whether or not it is the AESA calculation timing regardless of whether the fuel pump 30 is abnormal (S801). AESA is the fuel ignition timing in the engine 60. The ECU 20 calculates the ignition timing when the ignition timing of the engine 60 comes in the basic routine of engine control.
The ECU 20 calculates the rotational speed NE of the engine 60 in order to calculate AESA (S802). Further, the ECU 20 calculates the load P of the engine 60 (S803). Further, the ECU 20 detects the state of the engine 60 (S804). Here, the calculation of the rotational speed NE of the engine 60, the calculation of the load P of the engine 60, and the detection of the state of the engine 60 are the same as in the first embodiment for ensuring safety, and thus the description thereof is omitted.

  When the ECU 20 calculates the rotational speed NE of the engine 60 and the load P of the engine 60 and detects the state of the engine 60, the ECU 20 determines whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S805). As described above, when abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.

  When FFPF = 1, the ECU 20 sets the fuel pressure correction advance amount APF as APF = α and sets a predetermined correction value α (S806). The fuel pressure correction advance amount APF corrects the ignition timing to the advance side in order to reduce fluctuations in the output torque of the engine 60 when the fuel injection amount decreases due to the stop of the fuel pump 30 due to the detection of abnormality. It is a coefficient. On the other hand, when FFPF = 0 where no abnormality of the fuel pump 30 is detected, the ECU 20 sets APF = 0 (S807). That is, the ignition timing is not corrected to the advance side.

  When the fuel pressure correction advance amount APF is set, the ECU 20 calculates AESA according to the following equation 2 (S808). The ECU 20 corrects the reference ignition timing ABSE with the APF calculated in step S806 and various parameters. The reference ignition timing ABSE is obtained from the rotational speed NE of the engine 60 calculated in step S802 and the load P of the engine 60 calculated in step S803. The ECU 20 reads out the ABSE recorded in the ROM 22 as a map, for example. The various parameters for correcting ABSE are, for example, the intake air temperature THA, the coolant temperature THW, the atmospheric pressure PA, etc. detected in step S804. The ECU 20 adds correction values and APFs according to various parameters to the set ABSE. Therefore, the ECU 20 calculates AESA by the following equation 2.

AESA = ABSE + f (THA, THW, PA,...) + APF Equation 2
When AESA is calculated, ECU 20 outputs a control signal to ignition device 65 based on the calculated AESA. Thereby, in the ignition device 65, the ignition timing shifts to the advance side in accordance with the ABSE output from the ECU 20 (S809).

  In the second embodiment for ensuring safety, when the fuel pump 30 is stopped and the fuel discharged from the fuel pump 30 is lowered, the ignition timing is switched to the advance side. Thereby, even if the pressure of the fuel discharged from the fuel pump 30 is reduced and the amount of fuel injected from the injector 64 is reduced, the reduction in the output torque of the engine 60 is minimized. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

  In the above-described second embodiment for ensuring safety, the example in which the APF is fixed to the predetermined value α in step S806 has been described. However, the APF may be a value determined stepwise according to the rotational speed NE of the engine 60, or may be obtained as a function depending on the rotational speed NE of the engine 60.

3. Third Embodiment for Ensuring Safety In the third embodiment for ensuring safety, the TAU calculation method is different from the first embodiment for ensuring safety shown in FIG. Therefore, differences from the first embodiment of ensuring safety shown in FIG. 10 will be described based on FIG.
In the third embodiment for ensuring safety, the method from step S704 to step S708 in the flow shown in FIG. 10 is different. Therefore, it is determined whether it is the TAU calculation timing according to the flow shown in FIG. 10 (S701), the calculation of the rotational speed NE of the engine 60 (S702), the calculation of the load P of the engine 60 (S703), and the engine state When the detection (S704) ends, the process proceeds to step S901 shown in FIG.

When the ECU 20 calculates the rotational speed NE of the engine 60 and the load P of the engine 60 and detects the state of the engine 60, the ECU 20 determines whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S902). When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.
When FFPF = 1, the ECU 20 determines whether or not the pump abnormality mode coefficient counter CFPF is CFPF = 1 (S903). When the transition to the flow shown in FIG. 12 is made for the first time, CFPF is CFPF = 0. Therefore, the ECU 20 sets the fuel pressure correction coefficient FPF to FPF = 1.0 (S904).

  When the fuel pressure correction coefficient FPF is set to FPF = 1.0, the ECU 20 advances the CFPF count by one (S905). And it returns to step S708 shown in FIG. 10, and sets TAU using the set FPF. When the routine proceeds to the routine shown in FIG. 12, FPF = 1 is set. Therefore, the ECU 20 sets the TAU without correcting the reference injection pulse width TP with the FPF.

  When the routine proceeds to the routine shown in FIG. 12 and CFPF = 0, the fuel pump 30 is immediately after stopping. Therefore, the pressure of the fuel discharged from the fuel pump 30 is sufficiently maintained. Therefore, when CFPF = 0, the ECU 20 sets TAU without correcting TP by FPF. Therefore, fuel is injected according to TP.

  When the routine shown in FIG. 12 is performed for the second time or later, it is not determined in step S903 that CFPF = 0. Therefore, the ECU 20 compares the CFPF with a preset constant α (S910). The constant α is a value indicating whether or not the fuel pressure injected from the injector 64 is maintained after the fuel pump 30 is stopped, and indicates the number of fuel injections from the injector 64 performed after the fuel pump 30 is stopped. ing. Therefore, when CFPF is greater than or equal to α, a sufficient number of fuel injections are performed after the fuel pump 30 is stopped, and it is determined that the fuel pressure is substantially equal to the atmospheric pressure. On the other hand, when CFPF is smaller than α, the number of fuel injections after the fuel pump 30 is stopped is small, and it is determined that the fuel discharged from the fuel pump 30 has a pressure higher than the atmospheric pressure.

Therefore, if it is determined in step S910 that CFPF ≧ α, the ECU 20 sets the square root of the reference fuel pressure PF0 as the FPF (S911). Then, the ECU 20 advances one CFPF (S905), and then returns to step S708 (S906).
On the other hand, if it is determined in step S910 that CFPF <α, the ECU 20 sets the value shown in the following expression 3 as the FPF (S912).

FPF = {PF0 / (PF0−DPF × CFPF)} ^1/2 Formula 3
Here, the DPF is the pressure of the fuel that decreases per one injection of fuel from the injector 64. CFPF corresponds to the number of fuel injections. Therefore, the FPF set by Expression 3 is set stepwise in consideration of the pressure of the fuel that decreases with each fuel injection after the fuel pump 30 is stopped.

When the FPF is set in step S912, the ECU 20 advances the CFPF by one (S905), and then returns to step S708 (S906).
When it is determined in step S902 that FFPF = 1 is not satisfied, that is, abnormality of the fuel pump 30 has not been detected, the ECU 20 sets CFPF = 0 (S921), and sets FPF = 1.0 (S922). Therefore, when there is no abnormality in the fuel pump 30, a normal injection amount of fuel is injected from the injector 64.

  As described above, in the third embodiment for ensuring safety, when the fuel is injected from the injector 64 after the fuel pump 30 is stopped, the ECU 20 takes into consideration the fuel pressure that decreases each time the fuel is injected. A fuel pressure correction coefficient FPF is set. Therefore, even after the fuel pump 30 is stopped, a predetermined fuel injection amount is ensured even if the pressure of the fuel supplied to the injector 64 changes. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

  In the above-described third embodiment for ensuring safety, the example in which the FPF is calculated according to the number of fuel injections in steps S903 to S905 has been described. However, the FPF may set a value in advance according to the number of times of fuel injection from the injector 64 after the fuel pump 30 is stopped, and may be recorded in the ROM 22.

4). Fourth Embodiment for Ensuring Safety In the fourth embodiment for ensuring safety, the method for calculating AESA is different from the second embodiment for ensuring safety shown in FIG. Therefore, differences from the second embodiment of ensuring safety shown in FIG. 11 will be described based on FIG.
In the fourth embodiment for ensuring safety, the method from step S804 to step S808 in the flow shown in FIG. 11 is different. Therefore, it is determined whether or not it is the time to calculate AESA according to the flow shown in FIG. 11 (S801), the calculation of the rotational speed NE of the engine 60 (S802), the calculation of the load P of the engine 60 (S803), and the engine state When the detection (S804) ends, the process proceeds to step S1001 shown in FIG.

When the ECU 20 calculates the rotational speed NE of the engine 60 and the load P of the engine 60 and detects the state of the engine 60, the ECU 20 determines whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S1002). When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.
When FFPF = 1, the ECU 20 determines whether or not the pump abnormality mode coefficient counter CFPF is CFPF = 1 (S1003). When moving to the flow shown in FIG. 13, CFPF is CFPF = 0. Accordingly, the ECU 20 sets the fuel pressure correction advance amount APF as APF = 0 (S1004).

  When the fuel pressure correction advance amount APF is set to APF = 1.0, the ECU 20 advances the count of CFPF by one (S1005). And it returns to step S808 shown in FIG. 11, and sets AESA using the set APF. When the process proceeds to the routine shown in FIG. 13 for the first time, APF = 0 is set. Therefore, the ECU 20 sets AESA without correcting the reference ignition timing ABSE with the APF.

  When the routine proceeds to the routine shown in FIG. 13 and CFPF = 0, the fuel pump 30 is immediately after stopping. Therefore, the pressure of the fuel discharged from the fuel pump 30 is sufficiently maintained. Therefore, when CFPF = 0, the ECU 20 sets AESA without correcting ABSE with APF. Therefore, the ignition timing is set according to ABSE.

  When the routine shown in FIG. 13 is performed for the second time or later, it is not determined that CFPF = 0 in step S1003. Therefore, the ECU 20 compares the CFPF with a preset constant β (S1010). The constant β is a value indicating the number of times combustion has been performed in the engine 60 after the fuel pump 30 is stopped. Therefore, when CFPF is equal to or larger than β, it is determined that the engine 60 is burned a sufficient number of times after the fuel pump 30 is stopped. On the other hand, when CFPF is smaller than β, it is determined that the number of combustions in the engine 60 after the fuel pump 30 is stopped is small.

Therefore, if it is determined in step S1010 that CFPF ≧ β, the ECU 20 sets a correction value γ set in advance as the APF. The ECU 20 advances one CFPF (S1005), and then returns to step S808 (S1006).
On the other hand, if it is determined in step S1010 that CFPF <β, the ECU 20 sets a value shown in the following expression 4 as the APF (S1012).

APF = DA × CFPF Formula 4
Here, DA is an advance correction value set for each combustion in the engine 60. CFPF corresponds to the number of combustions in the engine 60. Therefore, in the APF set by Expression 4, the advance amount is set in consideration of the pressure of the fuel that decreases with each combustion in the engine 60 after the fuel pump 30 is stopped.

When the APF is set in step S1012, the ECU 20 advances the CFPF by one (S1005), and then returns to step S808 (S1006).
When it is determined in step S1002 that FFPF = 1 is not satisfied, that is, abnormality of the fuel pump 30 is not detected, the ECU 20 sets CFPF = 0 (S1021), and sets APF = 0 (S1022). Therefore, when no abnormality occurs in the fuel pump 30, the injection timing is not advanced.

  As described above, in the fourth embodiment for ensuring safety, when the combustion is performed in the engine 60 after the fuel pump 30 is stopped, the ECU 20 takes into account the fuel pressure that decreases every time the engine 60 is combusted. The fuel pressure correction advance amount APF is set. Therefore, even if the fuel pressure changes after the fuel pump 30 is stopped, the output torque of the engine 60 is ensured by correcting the injection timing to the advance side. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

  In the above-described fourth embodiment for ensuring safety, the example in which the APF is calculated according to the number of combustions in the engine 60 in steps S1003 to S1005 has been described. However, the APF may set a value corresponding to the number of combustions in the engine 60 after the fuel pump 30 is stopped in advance and record it in the ROM 22.

5. Fifth Embodiment for Ensuring Safety In the fifth embodiment for ensuring safety, the TAU calculation method is different from the first embodiment for ensuring safety shown in FIG. 10 as in the third embodiment for ensuring safety. Therefore, a fifth embodiment for ensuring safety will be described with reference to FIG.
The ECU 20 determines whether or not it is the TAU calculation timing in the flow shown in FIG. 10 (S701), calculates the rotational speed NE of the engine 60 (S702), calculates the load P of the engine 60 (S703), and the engine state. When the detection (S704) ends, the process proceeds to step S1101 shown in FIG. 14, and it is determined whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S1102). When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.

  When FFPF = 1, the ECU 20 determines whether or not the pump abnormality mode coefficient counter CFPF is CFPF = 1 (S1103). When the transition to the flow shown in FIG. 14 is made for the first time, CFPF is CFPF = 0. Therefore, the ECU 20 determines that the fuel is injected for the first time after an abnormality is detected in the fuel pump 30 and the fuel pump 30 is stopped. Therefore, the ECU 20 sets SUMINJ = 0 as the effective fuel injection time integrated value SUMINJ (S1104). The effective fuel injection time integration value SUMINJ is literally an integration of the time when fuel is actually injected from the injector 64. When the fuel is injected for the first time after the fuel pump 30 stops, the pressure of the fuel discharged from the fuel pump 30 is maintained. Therefore, the ECU 20 sets the fuel pressure correction coefficient FPF to FPF = 1.0 (S1105).

  When the fuel pressure correction coefficient FPF is set to FPF = 1, the ECU 20 advances the CFPF count by one (S1106). Then, the process returns to step S708 shown in FIG. 10 (S1107), and TAU is set using the set FPF. When the process proceeds to the routine shown in FIG. 14 for the first time, FPF = 1 is set. Therefore, the ECU 20 sets the TAU without correcting the reference injection pulse width TP with the FPF.

  When the routine proceeds to the routine shown in FIG. 14 and CFPF = 0, it is the first fuel injection after the fuel pump 30 stops. Therefore, the pressure of the fuel discharged from the fuel pump 30 is sufficiently maintained. Therefore, when CFPF = 0, the ECU 20 sets TAU without correcting TP by FPF. Therefore, fuel is injected according to TP.

  When the routine shown in FIG. 14 is performed for the second time or later, it is not determined that CFPF = 0 in step S1103. Therefore, the ECU 20 adds the previous effective fuel injection time INJ0 to SUMINJ (S1111). Here, the previous effective fuel injection time INJ0 is obtained by subtracting the invalid fuel injection time TV0 in the previous injection from the final fuel injection period TAU0 set in the previous injection, and the fuel pressure set in the previous injection. It is a value divided by the correction coefficient FPF0.

  After calculating SUMINJ, the ECU 20 calculates a fuel pressure PF corresponding to the calculated SUMINJ (S1112). The relationship between SUMINJ and PF is recorded in the ROM 22 of the ECU 20 as a map, for example. The ECU 20 calculates the FPF using the calculated PF. ECU20 sets the value shown to the following formula | equation 5 as FPF (S1113).

FPF = (PF0 / PF) ^1/2 Formula 5
Here, PF0 is the reference fuel pressure.
When the FPF is set in step S1113, the ECU 20 advances the CFPF by one (S1006), and then returns to step S708 (S1107).

  When it is determined in step S1102 that FFPF = 1 is not satisfied, that is, abnormality of the fuel pump 30 has not been detected, the ECU 20 sets CFPF = 0 (S1121) and sets FPF = 1.0 (S1122). Therefore, when there is no abnormality in the fuel pump 30, a normal injection amount of fuel is injected from the injector 64.

  As described above, in the fifth embodiment for ensuring safety, the ECU 20 integrates the fuel injection time from the injector 64 after the fuel pump 30 is stopped. When fuel is injected from the injector 64 after the fuel pump 30 is stopped, the fuel pressure decreases according to the injection time. Therefore, the fuel injection time from the injector 64 is integrated, and the fuel pressure correction coefficient FPF is set in consideration of the integrated fuel injection time. Therefore, a predetermined fuel injection amount is ensured regardless of the change in fuel pressure after the fuel pump 30 is stopped. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

6). Sixth Embodiment for Ensuring Safety When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, the ECU shifts to an abnormality return routine shown in FIG. 6 and returns the fuel pump 30 to a normal state. At this time, as shown in FIG. 6, the fuel pump 30 is stopped for a certain period. Therefore, the pressure of the fuel supplied from the fuel pump 30 to the engine 60 decreases. Therefore, in the sixth embodiment for ensuring safety, when an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4 and the fuel pump 30 is stopped, the fuel is injected from the injector 64 according to the procedure shown in FIG. The amount is forcibly increased to ensure stable operation of the engine 60.

The ECU 20 determines whether or not it is the TAU calculation timing regardless of whether the fuel pump 30 is abnormal (S1201). When the fuel injection timing of the injector 64 comes, the ECU 20 proceeds to TAU calculation.
The ECU 20 calculates the rotational speed NE of the engine 60 in order to calculate TAU (S1202). Further, the ECU 20 calculates the load P of the engine 60 (S1203). Calculation of the rotational speed NE of the engine 60 and the load P of the engine 60 is the same as in the first embodiment for ensuring safety. Further, the ECU 20 detects the state of the engine 60 (S1204). The ECU 20 detects the state of the engine 60 from the intake air temperature THA, the coolant temperature THW, the atmospheric pressure PA, and the like, as in the first embodiment for ensuring safety.

When the ECU 20 calculates the rotational speed NE of the engine 60 and the load P of the engine 60 and detects the state of the engine 60, the ECU 20 determines whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S1205). When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.
When FFPF = 1, the ECU 20 sets the square root of the reference fuel pressure PF0 as the fuel pressure correction coefficient FPF (S1206). The fuel pressure correction coefficient is a coefficient for correcting the discharge pressure from the fuel pump 30 that decreases due to the stop of the fuel pump 30 due to the detection of abnormality. The reference fuel pressure PF0 is the pressure of the fuel discharged from the fuel pump 30. Then, the ECU 20 sets a predetermined value δ as the pump abnormality correction coefficient FFPFS (S1207). The pump abnormality correction coefficient FFPFS is a coefficient for increasing the fuel injection amount, that is, enriching the fuel in consideration of a decrease in fuel pressure accompanying the stoppage of the fuel pump 30. Even if the fuel pressure decreases due to the stop of the fuel pump 30, the total amount of fuel injected from the injector 64 increases due to the FFPFS.

On the other hand, when FFPF = 0 where no abnormality of the fuel pump 30 is detected, the ECU 20 sets FPF = 1.0 (S1211). Further, the ECU 20 sets FFPFS = 1.0 (S1212). That is, when no abnormality of the fuel pump 30 is detected, the correction coefficient is not set.
When the fuel pressure correction coefficient FPF and the pump abnormality correction coefficient FFPFS are set, the ECU 20 calculates TAU according to the following equation 6 (S1208). The ECU 20 corrects the reference injection pulse width TP with the FPF calculated in step S1206, the FFPFS calculated in step S1207, and various parameters. The reference injection pulse width TP is obtained from the rotational speed NE of the engine 60 calculated in step S1202 and the engine load P calculated in step S703 as described in the first embodiment for ensuring safety. The various parameters for correcting TP are, for example, the intake air temperature THA, the coolant temperature THW, the atmospheric pressure PA, etc. detected in step S1204. The ECU 20 corrects the set TP with FPF, FFPFS, and various parameters, and adds the invalid injection time TV of the injector 64. Therefore, the ECU 20 calculates TAU according to the following formula 6.
TAU = TP × f (THA, THW, PA,...) × FPF × FFFPFS + TV Equation 6

When the TAU is calculated, the ECU 20 outputs a control signal to the injector 64 based on the calculated TAU. Thereby, fuel is injected from the injector 64 according to the control signal output from the ECU 20 (S1209).
In the sixth embodiment for ensuring safety, when the fuel pump 30 stops and the pressure of the fuel discharged from the fuel pump 30 decreases, the fuel that injects fuel from the injector 64 increases. Thereby, even if the pressure of the fuel discharged from the fuel pump 30 decreases, the total amount of fuel injected from the injector 64 does not change greatly. As a result, even when the fuel pump 30 is stopped by detecting an abnormality in the fuel pump 30, a predetermined amount of fuel is injected into the engine 60. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

  In the above-described sixth embodiment for ensuring safety, the example in which FFPFS is set to the predetermined value δ in step S1207 has been described. However, FFPFS may be recorded in the ROM 22 as a map of coefficients that change depending on the load P of the engine 60, for example, and may be used after interpolation calculation. The FFPFS may be recorded in the ROM 22 as a map of coefficients that change depending on both the load P of the engine 60 and the rotational speed NE of the engine 60, and may be used after interpolation calculation. Further, FFPFS may be calculated based on the load P of the engine 60 detected in step S1203 as a function of the load P of the engine 60.

7). Seventh Embodiment for Ensuring Safety In the seventh embodiment for ensuring safety, the TAU calculation method in the sixth embodiment for ensuring safety is different. A seventh embodiment for ensuring safety will be described with reference to FIG.
The ECU 20 determines whether or not it is the TAU calculation timing in the flow shown in FIG. 15 (S1201), calculates the rotational speed NE of the engine 60 (S1202), calculates the load P of the engine 60 (S1203), and the engine state When the detection (S1204) is completed, the process proceeds to step S1301 shown in FIG. 16, and it is determined whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S1302). When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.

  When FFPF = 1, the ECU 20 determines whether or not the pump abnormality mode coefficient counter CFPF is CFPF = 1 (S1303). When the transition to the flow shown in FIG. 16 is made for the first time, CFPF is CFPF = 0. Therefore, the ECU 20 determines that the fuel injection is the first fuel injection after the abnormality is detected in the fuel pump 30 and the fuel pump 30 is stopped. When the fuel is injected for the first time after the fuel pump 30 is stopped, the pressure of the fuel discharged from the fuel pump 30 is maintained. Therefore, the ECU 20 sets the fuel pressure correction coefficient FPF to FPF = 1.0 (S1304).

  When the fuel pressure correction coefficient FPF = 1.0 is set, the ECU 20 sets the pump abnormality correction coefficient FFPFS to FFPFS = 1.0 (S1305). As described in the sixth embodiment for ensuring safety, the pump abnormality correction coefficient FFPFS is a coefficient for increasing the fuel injection amount, that is, to enrich the fuel in consideration of a decrease in the fuel pressure accompanying the stop of the fuel pump 30. It is.

  When the ECU 20 sets FPF and FFPFS, the ECU 20 advances the count of CFPF by one (S1306). And it returns to step S1208 shown in FIG. 15, and sets TAU using the set FPF and FFPFS. When the routine shifts to the routine shown in FIG. 16, FPF = 1.0 and FFPFS = 1.0 are set. Therefore, the ECU 20 sets TAU without correcting the reference injection pulse width TP with FPF and FFPFS.

  When the routine shown in FIG. 16 is performed for the second time or later, it is not determined in step S1303 that CFPF = 0. Therefore, the ECU 20 compares CFPF with a preset constant α (S1311). The constant α indicates the number of fuel injections from the injector 64 as described in the third embodiment for ensuring safety. Therefore, when the CFPF is greater than or equal to α, it is determined that the fuel pressure is almost equal to the atmospheric pressure. When the CFPF is smaller than α, the fuel discharged from the fuel pump 30 has a pressure greater than the atmospheric pressure. To be judged.

  Therefore, if it is determined in step S1311 that CFPF ≧ α, the ECU 20 sets the square root of the reference fuel pressure PF0 as the FPF (S1312). Then, the ECU 20 sets the pump abnormality correction coefficient FFPFS to a predetermined value μ (S1313). Thus, when CFPF is greater than or equal to α, it is determined that the pressure of the fuel discharged from the fuel pump 30 is substantially equal to the atmospheric pressure, and the fuel injection amount is increased according to the predetermined value μ. When FPF and FFPFS are set, ECU 20 advances CFPF by one (S1206), and then returns to step S1208 (S1307).

On the other hand, if it is determined in step S1311 that CFPF <α, the ECU 20 sets a value shown in the following expression 7 as the FPF (S1314).
FPF = {PF0 / (PF0−DPF × CFPF)} ^1/2 Formula 7
Here, the DPF is the pressure of the fuel that decreases per one injection of fuel from the injector 64. CFPF corresponds to the number of fuel injections. Therefore, the FPF set by Expression 7 is set stepwise in consideration of the pressure of the fuel that decreases with each fuel injection after the fuel pump 30 is stopped.

When FPF is set in step S1314, the ECU 20 sets FFPFS = γ (S1313), advances one CFPF (S1306), and returns to step S1208 (S1307).
When it is determined in step S1302 that FFPF = 1 is not satisfied, that is, abnormality of the fuel pump 30 is not detected, the ECU 20 sets CFPF = 0 (S1321), sets FPF = 1.0 (S1322), and FFPFS. = 1.0 is set (S1323). Therefore, when there is no abnormality in the fuel pump 30, a normal injection amount of fuel is injected from the injector 64.

  As described above, in the seventh embodiment for ensuring safety, when the fuel is injected from the injector 64 after the fuel pump 30 is stopped, the ECU 20 takes into consideration the fuel pressure that decreases each time the fuel is injected. The fuel pressure correction coefficient FPF is set, and the fuel injection amount is corrected together with the pump abnormality correction coefficient FFPFS. Therefore, a predetermined fuel injection amount is ensured regardless of the change in fuel pressure after the fuel pump 30 is stopped. Therefore, the operation of the engine 60 can be continued stably, and safety can be ensured.

  In the seventh embodiment for ensuring safety described above, the example in which FFPFS is set to the predetermined value μ in steps S1305 and S1313 has been described. However, FFPFS may be calculated as a function or a map such as the load P of the engine 60 and the rotational speed NE of the engine 60 as in the sixth embodiment for ensuring safety.

8). Eighth Embodiment for Ensuring Safety In the eighth embodiment for ensuring safety, the TAU calculation method in the sixth embodiment for ensuring safety is different. Accordingly, an eighth embodiment for ensuring safety will be described with reference to FIG.
The ECU determines whether or not it is the TAU calculation timing in the flow shown in FIG. 15 (S1201), calculates the rotational speed NE of the engine 60 (S1202), calculates the load P of the engine 60 (S1203), and the engine state When the detection (S1204) ends, the process proceeds to step S1401 shown in FIG. 17, and it is determined whether or not the pump abnormality determination flag FFPF is FFPF = 1 (S1402). When an abnormality is detected in the fuel pump 30 by the procedure shown in FIG. 4, FFPF = 1.

  When FFPF = 1, the ECU 20 determines whether or not the pump abnormality mode coefficient counter CFPF is CFPF = 1 (S1403). When the transition to the flow shown in FIG. 17 is made for the first time, CFPF is CFPF = 0. Therefore, the ECU 20 determines that this is the first fuel injection after an abnormality is detected in the fuel pump and the fuel pump stops. When the fuel is injected for the first time after the fuel pump 30 is stopped, the pressure of the fuel discharged from the fuel pump 30 is maintained. Therefore, the ECU 20 sets the fuel pressure correction coefficient FPF to FPF = 1.0 (S1404).

  When the fuel pressure correction coefficient FPF = 1.0 is set, the ECU 20 sets the pump abnormality correction coefficient FFPFS as FFPFS = 1.0 (S1405). As described in the sixth embodiment for ensuring safety, the pump abnormality correction coefficient FFPFS is a coefficient for increasing the fuel injection amount, that is, to enrich the fuel in consideration of a decrease in the fuel pressure accompanying the stop of the fuel pump 30. It is.

  When the ECU 20 sets FPF and FFPFS, the ECU 20 advances the count of CFPF by one (S1406). And it returns to step S1208 shown in FIG. 15, and sets TAU using the set FPF and FFPFS. When the routine shifts to the routine shown in FIG. 17, FPF = 1.0 and FFPFS = 1.0 are set. Therefore, the ECU 20 sets TAU without correcting the reference injection pulse width TP with FPF and FFPFS.

  When the routine shown in FIG. 17 is performed for the second time or later, it is not determined that CFPF = 0 in step S1403. Therefore, the ECU 20 compares the CFPF with a preset constant α (S1411). The constant α indicates the number of fuel injections from the injector 64 as described in the third embodiment for ensuring safety. Therefore, when the CFPF is greater than or equal to α, it is determined that the fuel pressure is almost equal to the atmospheric pressure. When the CFPF is smaller than α, the fuel discharged from the fuel pump 30 has a pressure greater than the atmospheric pressure. To be judged.

  Therefore, if it is determined in step S1411 that CFPF ≧ α, the ECU 20 sets the square root of the reference fuel pressure PF0 as the FPF (S1412). On the other hand, if it is determined in step S1411 that CFPF <α, the ECU 20 sets the value shown in the following expression 8 as the FPF (S1414).

FPF = {PF0 / (PF0−DPF × CFPF)} ^1/2 Formula 8
Here, the DPF is the pressure of the fuel that decreases per one injection of fuel from the injector 64. CFPF corresponds to the number of fuel injections. Therefore, the FPF set by Expression 8 is set stepwise in consideration of the pressure of the fuel that decreases with each fuel injection after the fuel pump 30 is stopped.
When FPF is set in step S1412 and step S1421, ECU 20 determines whether or not engine 60 is starting (S1413). Here, the time when the engine 60 is started is, for example, when the engine 60 is warming up immediately after starting, and when the temperature THW of the cooling water has not reached a predetermined temperature, or when the engine 60 is started. Until a predetermined time elapses. The definition at the start of the engine 60 can be arbitrarily set.

  If the ECU 20 determines that the engine 60 is at the time of starting, it sets FFPFS = ρ (S1415). When the engine 60 is started, since the operation of the engine 60 is relatively unstable, it is necessary to enrich the fuel injected from the injector 64. Therefore, ρ set in step S1415 is a value for correcting the fuel injection amount to the rich side. Ρ as the value of FFPFS is recorded in the ROM 22 as a numerical value that varies depending on the value of CFPF, for example, as shown in FIG.

  On the other hand, if the ECU 20 determines in step S1413 that the engine 60 is not at the time of starting, it determines whether or not the rotational speed NE of the engine 60 is equal to or less than a predetermined value K set in advance (S1431). The ECU 20 determines that the engine 60 is in the low rotation speed region if the rotational speed NE of the engine 60 detected in step S1202 shown in FIG. Further, ECU 20 determines that engine 60 is in the high engine speed region if rotational speed NE of engine 60 is greater than predetermined value K. If the ECU 20 determines in step S1431 that the rotational speed NE of the engine 60 is in the low rotational speed region of the predetermined value K or less, it sets FFPFS = σ (S1432). For example, as shown in FIG. 19, σ as the value of FFPFS is recorded in the ROM 22 as a numerical value that varies depending on the CFPF.

In contrast, if the ECU 20 determines in step S1431 that the rotational speed NE of the engine 60 is greater than the predetermined value K, it sets FFPFS = κ (S1433). For example, as shown in FIG. 20, κ as the value of FFPFS is recorded in the ROM 22 as a numerical value that varies depending on NE.
As described above, the ECU 20 sets FFPFS in accordance with the start of the engine 60 and the rotational speed of the engine 60. Thereby, the quantity of the fuel injected from the injector 64 can be changed according to the concentration of the required fuel.

When the pump abnormality correction coefficient FFPFS is set to the predetermined value ρ, σ, or κ, the ECU 20 advances CFPF by one (S1406), and then returns to step S1208 (S1407).
When it is determined in step S1402 that FFPF = 1 is not satisfied, that is, abnormality of the fuel pump 30 is not detected, the ECU 20 sets CFPF = 0 (S1421), sets FPF = 1.0 (S1422), and FFPFS. = 1.0 is set (S1423). Therefore, when there is no abnormality in the fuel pump 30, a normal injection amount of fuel is injected from the injector 64.

  As described above, in the eighth embodiment for ensuring safety, when the fuel is injected from the injector 64 after the fuel pump 30 is stopped, the ECU 20 takes into consideration the fuel pressure that decreases each time the fuel is injected. The fuel pressure correction coefficient FPF is set, and the fuel injection amount is corrected together with the pump abnormality correction coefficient FFPFS. Further, the pump abnormality correction coefficient FFPFS varies depending on the operating state of the engine 60, that is, whether or not the engine 60 is being started, and the rotational speed of the engine 60. Therefore, a predetermined fuel injection amount is ensured regardless of the change in fuel pressure after the fuel pump 30 is stopped and the state of the engine 60. Therefore, the engine 60 can be reliably started or the operation of the engine 60 can be stably continued, and safety can be ensured.

(Second Embodiment of Fuel Pump Control Device)
A fuel pump control apparatus according to the second embodiment of the present invention is shown in FIG. In addition, the same code | symbol is attached | subjected to the substantially same component as 1st Embodiment of the control apparatus of the fuel pump shown in FIG. 1, and description is abbreviate | omitted.
In the case of the second embodiment of the fuel pump control device, the fuel pump control device 110 includes the fuel pump 30 housed in the fuel tank 70. That is, in the case of the second embodiment, the fuel pump 30 is accommodated in the fuel tank 70. The control device 110 includes a liquid level sensor 71 as fuel remaining amount detecting means for detecting the remaining amount of fuel stored in the fuel tank 70. The liquid level sensor 71 detects the liquid level position of the fuel that moves up and down in the fuel tank 70. The liquid level sensor 71 includes, for example, a sender gauge integrated with the fuel pump 30, a sensor provided in the fuel tank 70, and the like. The control unit 11 of the control device 110 functions as an abnormality detection means in the scope of claims similar to the first embodiment of the control device for the fuel pump.

The other configuration is substantially the same as that of the first embodiment of the fuel pump control device shown in FIG.
Next, the abnormality detection procedure of the fuel pump 30 by the fuel pump control device 110 will be described with reference to FIG.

1. First Embodiment of Abnormality Detection Based on Fuel Remaining The ECU 20 executes an abnormality determination routine as to whether or not an abnormality of the fuel pump 30 has occurred at a predetermined time. The abnormality determination routine is included as one of routines for monitoring the entire vehicle by the ECU 20, for example, and is periodically performed after the engine 60 is started. When the routine proceeds to the abnormality determination routine, the ECU 20 first detects the voltage B of the battery 14 (S1501). The ECU 20 obtains the voltage B of the battery 14 from the voltage detection unit 24. The ECU 20 records the obtained voltage B of the battery 14 in the RAM 23. When detecting the voltage of the battery 14, the ECU 20 detects the rotational speed NP of the brushless motor 32 of the fuel pump 30 (S1502). The ECU 20 obtains the rotational speed NP of the brushless motor 32 from the rotational speed detection unit 13 of the control circuit unit 12. The ECU 20 records the obtained rotational speed NP of the brushless motor 32 in the RAM 23.

  The ECU 20 calculates the reference rotational speed NP0 of the brushless motor 32 corresponding to the voltage B of the battery 14 obtained in step S1501 and recorded in the RAM 23 from the map recorded in the ROM 22 (S1503). The ECU 20 records the calculated reference rotational speed NP0 in the RAM 23. When the reference rotational speed NP0 is calculated, the ECU 20 calculates an upper limit value NP0 + α according to the reference rotational speed NP0.

  Further, the ECU 20 detects the remaining amount QF of the fuel stored in the fuel tank 70 (S1504). The ECU 20 obtains the liquid level position of the fuel stored in the fuel tank 70 from the output value of the liquid level sensor 71, that is, the remaining amount of fuel. The ECU 20 records the remaining amount of fuel QF in the obtained fuel tank 70 in the RAM 23.

  When the upper limit value NP0 + α is calculated, the ECU 20 determines whether or not the rotational speed NP of the brushless motor 32 obtained in step S1502 is larger than the upper limit value NP0 + α (S1505). As described above, the brushless motor 32 and the fuel pump 30 including the brushless motor 32 have a distribution as shown in FIG. Even if the product variations of the brushless motor 32 and the fuel pump 30 are eliminated, the rotational speed NP of the brushless motor 32 with respect to the voltage B of the battery 14 varies depending on the remaining fuel amount QF. That is, the load of the brushless motor 32 decreases as the fuel remaining amount QF in the fuel tank 70 decreases. Therefore, even if the voltage B of the battery 14 is constant, the rotation speed NP of the brushless motor 32 increases.

  Therefore, the ECU 20 determines whether or not the rotational speed NP of the brushless motor 32 is greater than the upper limit value NP0 + α. When it is determined that the rotational speed NP of the brushless motor 32 is greater than the upper limit value NP0 + α, the ECU 20 further determines whether or not the remaining fuel amount QF recorded in step S1506 is greater than a predetermined remaining amount threshold value Q1. Is determined (S1506). Here, the ECU 20 determines that the brushless motor 32 or the fuel pump 30 is abnormal when the rotational speed NP of the brushless motor 32 is larger than the upper limit value NP0 + α and the remaining amount QF of fuel is larger than the remaining amount threshold value Q1 ( S1507). On the other hand, when the rotational speed NP of the brushless motor 32 is larger than the upper limit value NP0 + α and the remaining amount of fuel QF is smaller than the remaining amount threshold value Q1, the ECU 20 has a small amount of fuel remaining in the fuel tank 70. It is determined that there is a missing state (S1508).

As described above, when the rotational speed NP of the brushless motor 32 is larger than the upper limit value NP0 + α, the ECU 20 determines whether or not the remaining amount QF of fuel in the fuel tank 70 is larger than the remaining amount threshold value Q1. When the remaining amount QF of fuel in the fuel tank 70 is smaller than the remaining amount threshold value Q1, the fuel tank 70 is idling, and the rotation speed of the brushless motor 32 increases even if the voltage B of the battery 14 is constant. . Therefore, by detecting the remaining fuel amount QF in the fuel tank 70 together with the rotational speed NP of the brushless motor 32, whether the abnormality of the brushless motor 32 and the fuel pump 30 is due to their own abnormality or not is in a gas-out state. It can be determined whether it is caused or not.
The fuel pump abnormality detection is completed by the above procedure.

2. Second Embodiment of Abnormality Detection Based on Fuel Remaining A second embodiment of abnormality detection by the control device 110 configured as described above will be described with reference to FIG. Note that detailed description of procedures substantially the same as those in the first embodiment of abnormality detection shown in FIG. 22 is omitted.
When the ECU 20 proceeds to the abnormality determination routine, it detects the voltage B of the battery 14 and records the detected voltage B of the battery 14 in the RAM 23 (S1601). Further, the ECU 20 detects the rotational speed NP of the brushless motor 32 of the fuel pump 30 and records the detected rotational speed NP of the brushless motor 32 in the RAM 32 (S1602). Further, the ECU 20 calculates a reference rotational speed NP0 of the brushless motor 32 corresponding to the voltage B from the voltage B of the battery 14 obtained in step S1601. Then, the ECU 20 calculates an upper limit value NP0 + α according to the calculated reference rotational speed NP0.

When the upper limit value NP0 + α is calculated, the ECU 20 sets the pump abnormality determination execution number counter CNPJAN to CNPJAN = CNPJAN + 1 and advances the counter by “1” (S1603).
When the pump abnormality determination execution counter CNPJAN is advanced by “1”, the ECU 20 compares the rotation speed NP of the brushless motor 32 detected in step S1602 with the upper limit value NP0 + α of the reference rotation speed NP0 (S1604). Here, when the ECU 20 determines that the rotational speed NP of the brushless motor 32 is smaller than the upper limit value NP0 + α, the ECU 20 ends the abnormality detection and proceeds to step S1612. On the other hand, when the ECU 20 determines that the rotational speed NP of the brushless motor 32 is larger than the upper limit value NP0 + α, the ECU 20 determines that the abnormality of the fuel pump 30 is detected, sets the pump abnormality detection counter CNPAN to CNPAN = CNPAN + 1, and advances the counter by “1”. (S1605).

  When the ECU 20 advances the pump abnormality detection counter CNPAN by “1”, the ECU 20 determines whether or not the pump abnormality determination execution counter CNPJAN counted in step S1603 is equal to or larger than a predetermined value C1 set in advance (S1606). That is, the ECU 20 determines whether or not a period corresponding to the predetermined value C1 corresponding to the predetermined period has elapsed. When the ECU 20 determines that the pump abnormality determination execution counter CNPJAN is smaller than the predetermined value C1, the ECU 20 ends the abnormality detection and proceeds to step S1612. On the other hand, when the ECU 20 determines that the pump abnormality determination execution counter CNPJAN is equal to or larger than the predetermined value C1, the ECU 20 determines whether or not the pump abnormality detection counter CNPAN counted in step S1605 is equal to or larger than a predetermined value C2. Determination is made (S1607). That is, the ECU 20 determines whether or not the pump abnormality detection counter CNPAN has been counted the number of times corresponding to the predetermined value C2 during the predetermined period C1 counted by the pump abnormality determination execution number counter CNPJAN. Here, the predetermined value C1 and the predetermined value C2 have a relationship of C1 ≧ C2.

  The ECU 20 determines that an abnormality has occurred in the fuel pump 30 or the brushless motor 32 when the pump abnormality detection counter CNPAN is equal to or greater than the predetermined value C2 (S1608). If an abnormality occurs in the fuel pump 30 or the brushless motor 32, the abnormality continues until the fuel pump 30 is restarted or reversely rotated, for example. Therefore, the value of the pump abnormality detection counter CNPAN in which an abnormality is detected in the fuel pump 30 or the brushless motor 32 is approximated to the count value C1 of the pump abnormality determination execution number counter CNPJAN. In particular, when an abnormality occurs in the fuel pump 30 or the brushless motor 32, the predetermined value C1 and the predetermined value C2 substantially coincide with each other.

  On the other hand, when the pump abnormality detection counter CNPAN is smaller than the predetermined value C2, the ECU 20 determines that a so-called out-of-gas state is present in which the remaining amount of fuel in the fuel tank 70 is small (S1609). When the remaining amount of fuel in the fuel tank 70 decreases, the fuel pump 30 intermittently discharges the fuel due to a change in the fuel level in the fuel tank 70. Therefore, the abnormality of the fuel pump 30 or the brushless motor 32 is detected intermittently. As a result, the value C1 of the count of the pump abnormality determination execution counter CNPJAN increases until the value of the pump abnormality detection counter CNPAN in which an abnormality is detected in the fuel pump 30 or the brushless motor 32 reaches the predetermined value C2.

  As described above, the ECU 20 determines whether an abnormality has occurred in the fuel pump 30 or the brushless motor 32 from the value of the pump abnormality determination execution counter CNPJAN and the value of the pump abnormality detection counter CNPAN, or the remaining fuel in the fuel tank 70. Determine if the amount is decreasing. When the ECU 20 determines that an abnormality has occurred in the fuel pump 30 or the brushless motor 32 or that the remaining amount of fuel in the fuel tank 70 has decreased, the ECU 20 resets the pump abnormality detection counter CNPAN to CNPAN = 0 ( S1610), the pump abnormality determination execution counter CNPJAN is reset to CNPJAN = 0 (S1611).

  The ECU 20 repeats the above processing until the pump abnormality determination execution counter CNPJAN reaches a predetermined value C3 (S1612). That is, when the ECU 20 proceeds from step S1604, step S1606, or step S1611 to step S1612, the ECU 20 determines whether or not the pump abnormality determination execution number counter CNPJAN is equal to or greater than a predetermined value C3. The predetermined value C3 is larger than the predetermined value C1 and the predetermined value C2. When the ECU 20 determines that the pump abnormality determination execution counter CNPJAN is equal to or greater than C3, the ECU 20 resets the pump abnormality determination execution counter CNPJAN to CNPJAN = 0 (S1613), and repeats the above-described processing again. On the other hand, if the ECU 20 determines that the pump abnormality determination execution counter CNPJAN is smaller than the predetermined value C3, the ECU 20 repeats the above processing until the pump abnormality determination execution counter CNPJAN reaches the predetermined value C3.

  As described above, in the present embodiment, whether the abnormality is caused by the fuel pump 30 or the brushless motor 32 or the fuel tank is detected from the frequency of the abnormality detected by the fuel pump 30 or the brushless motor 32 within a predetermined period. It can be determined whether the fuel is due to the remaining amount of fuel at 70.

3. Third Embodiment of Abnormality Detection Based on Fuel Remaining A third embodiment of abnormality detection by the control device 110 having the above configuration will be described with reference to FIG. Note that detailed description of procedures substantially the same as those of the first embodiment shown in FIG. 22 or the second embodiment shown in FIG. 23 is omitted.
When the ECU 20 proceeds to the abnormality determination routine, it detects the voltage B of the battery 14 and records the detected voltage B of the battery 14 in the RAM 23 (S1701). Further, the ECU 20 detects the rotational speed NP of the brushless motor 32 of the fuel pump 30 and records the detected rotational speed NP of the brushless motor 32 in the RAM 32 (S1702). Further, the ECU 20 calculates the reference rotational speed NP0 of the brushless motor 32 corresponding to the voltage B from the voltage B of the battery 14 obtained in step S1701. Then, the ECU 20 calculates an upper limit value NP0 + α according to the calculated reference rotational speed NP0.

  When the upper limit value NP0 + α is calculated, the ECU 20 compares the rotational speed NP of the brushless motor 32 detected in step S1702 with the upper limit value NP0 + α of the reference rotational speed NP0 (S1703). When the ECU 20 determines that the rotational speed NP of the brushless motor 32 is greater than the upper limit value NP0 + α, the ECU 20 determines that an abnormality has occurred in the fuel pump 30 or the brushless motor 32. Therefore, the ECU 20 sets the pump abnormality detection counter CNPAN to CNPAN = CNPAN + 1 and advances the counter by “1” (S1704). On the other hand, when the ECU 20 determines that the rotation speed NP of the brushless motor 32 is smaller than the upper limit value NP0 + α, the ECU 20 proceeds to the subsequent step without advancing the pump abnormality detection counter CNPAN.

  When step S1704 is completed, the ECU 20 determines whether or not the pump abnormality determination execution number counter CNPJAN has reached a predetermined value D1 (S1705). The pump abnormality determination execution number counter CNPJAN is advanced by “1” every time the abnormality determination routine shown in FIG. 24 is performed. Therefore, immediately after the transition to the abnormality determination routine, the pump abnormality determination execution counter CNPJAN is CNPJAN = 0. That is, in step S1705, it is determined whether or not the abnormality determination routine has been performed a number of times corresponding to the predetermined value D1. When the pump abnormality determination execution counter CNPJAN has not reached the predetermined value D1, the ECU 20 ends the abnormality detection and proceeds to step S1713.

  When the ECU 20 determines that the pump abnormality determination execution counter CNPJAN is the predetermined value D1, the ECU 20 determines whether or not the pump abnormality detection counter CNPAN counted in step S1704 is smaller than the predetermined value D2 (S1706). Here, the predetermined value D2 is set as a value smaller than the predetermined value D1. When the pump abnormality detection counter CNPAN is smaller than the predetermined value D2, the number of abnormality of the fuel pump 30 or the brushless motor 32 detected until the pump abnormality determination execution counter CNPJAN reaches the predetermined value D1 is smaller than the predetermined value D2. Therefore, the ECU 20 determines that the fuel pump 30 or the brushless motor 32 is normal when the pump abnormality detection counter CNPAN is smaller than the predetermined value D2.

  On the other hand, when the pump abnormality detection counter CNPAN is larger than the predetermined value D2, the ECU 20 further determines whether or not the pump abnormality detection counter CNPAN is smaller than the predetermined value D3 (S1708). The relationship among the predetermined value D3, the predetermined value D1, and the predetermined value D2 is set such that D1 ≧ D3> D2. Accordingly, when the pump abnormality detection counter CNPAN is smaller than the predetermined value D3, an abnormality is detected in the fuel pump 30 or the brushless motor 32 until the pump abnormality determination execution number counter CNPJAN reaches the predetermined value D1, but the frequency of the abnormality is detected. Is judged to be low. When the remaining amount of fuel in the fuel tank 70 decreases, the fuel is intermittently discharged from the fuel pump 30 depending on the fuel level in the fuel tank 70. As a result, the abnormality of the fuel pump 30 or the brushless motor 32 is detected intermittently and becomes smaller than the predetermined value D3. Therefore, when the value of the pump abnormality detection counter CNPAN is between the predetermined value D2 and the predetermined value D3, the ECU 20 determines that a so-called out-of-gas condition is present (S1709).

  Further, when the pump abnormality detection counter CNPAN is larger than the predetermined value D3, the ECU 20 determines that an abnormality has occurred in the fuel pump 30 or the brushless motor 32 (S1710). That is, when the pump abnormality detection counter CNPAN is larger than the predetermined value D3, the abnormality frequency detected by the fuel pump 30 or the brushless motor 32 is high before the pump abnormality determination execution number counter CNPJAN reaches the predetermined value D1. Therefore, it is considered that the fuel pump 30 or the brushless motor 32 is continuously abnormal. Therefore, the ECU 20 determines that an abnormality has occurred in the fuel pump 30 or the brushless motor 32 when the pump abnormality detection counter CNPAN is greater than the predetermined value D3.

When the ECU 20 determines whether there is an abnormality in the fuel pump 30 or the brushless motor 32 or the remaining amount of fuel in the fuel tank 70 is decreased, the ECU 20 resets the pump abnormality detection counter CNPAN to CNPAN = 0 (S1711) and determines the pump abnormality. The execution number counter CNPJAN is reset to CNPJAN = 0 (S1712).
When the above procedure ends, the ECU 20 advances the pump abnormality determination execution number counter CNPJAN by “1” (S1713).

  As described above, in the present embodiment, whether the abnormality is caused by the fuel pump 30 or the brushless motor 32 or the fuel tank is detected from the frequency of the abnormality detected by the fuel pump 30 or the brushless motor 32 within a predetermined period. It can be determined whether the fuel is due to the remaining amount of fuel at 70.

4). Ensuring safety when an abnormality is detected (1)
In the first embodiment, the second embodiment, or the third embodiment of the abnormality detection based on the remaining amount of fuel as described above, when a gas shortage in the fuel tank 70 or an abnormality in the fuel pump 30 or the brushless motor 32 is detected. The ECU 20 can perform processing for ensuring safety. Hereinafter, safety ensuring (1) at the time of abnormality detection will be described. Here, in the case of ensuring safety at the time of abnormality detection (1), the procedure up to detection of gas shortage in the fuel tank 70 or abnormality of the fuel pump 30 or the brushless motor 32 has been described with reference to FIG. 22, FIG. 23 or FIG. Street. Therefore, only the differences from the embodiments described in FIG. 22, FIG. 23, or FIG. 24 will be described, and the same step numbers will be assigned to other procedures, and description thereof will be omitted.

  For example, in the first embodiment of abnormality detection based on the remaining fuel amount shown in FIG. 22, the ECU 20 determines that the fuel pump 30 or the brushless motor 32 is abnormal in step S1507. At this time, as shown in FIG. 25, the ECU 20 warns of an abnormality of the fuel pump 30 via a warning means (S1511). On the other hand, in the first embodiment of abnormality detection based on the remaining amount of fuel shown in FIG. 22, the ECU 20 determines that there is a lack of fuel in the fuel tank 70 in step S1508. At this time, as shown in FIG. 25, the ECU 20 warns the decrease in the remaining amount of fuel in the fuel tank 70 via the warning means (S1512).

  Thus, the flow of the processing shown in FIG. 25 is a modification of the first embodiment of abnormality detection based on the remaining fuel amount shown in FIG. 22, and in step S1511 that warns of abnormality of the fuel pump 30 following step S1507, And step S1512 which warns of a gas shortage is included following step S1508. Here, the ECU 20 issues a warning of abnormality via, for example, visual, auditory or tactile warning means. For example, a blinking lamp on the dashboard can be applied as a visual warning means, a buzzer or horn ringing can be applied as an audible warning means, and a handle or shift knob vibration can be applied as a tactile warning means. can do. Thus, the warning means can be arbitrarily selected and applied.

  Further, in the second embodiment of abnormality detection based on the remaining fuel amount shown in FIG. 23, the ECU 20 determines that the fuel pump 30 or the brushless motor 32 is abnormal in step S1608. At this time, as shown in FIG. 26, the ECU 20 warns of an abnormality of the fuel pump 30 via a warning means (S1621). On the other hand, in the second embodiment of abnormality detection based on the remaining amount of fuel shown in FIG. 23, the ECU 20 determines that the fuel in the fuel tank 70 is out of fuel in step S1609. At this time, as shown in FIG. 26, the ECU 20 warns the decrease in the remaining amount of fuel in the fuel tank 70 via the warning means (S1622).

  As described above, the flow of the processing shown in FIG. 26 is a modification of the second embodiment of abnormality detection based on the remaining amount of fuel shown in FIG. 23. Following step S1608, warning of abnormality of the fuel pump 30 is performed in step S1621, And step S1622 which warns of a gas shortage is included following step S1609.

  Further, in the third embodiment of abnormality detection based on the remaining amount of fuel shown in FIG. 24, the ECU 20 determines that the fuel in the fuel tank 70 is out of gas in step S1709. At this time, as shown in FIG. 27, the ECU 20 warns the decrease in the remaining amount of fuel in the fuel tank 70 via a warning means (S1721). On the other hand, in the second embodiment of abnormality detection based on the remaining amount of fuel shown in FIG. 24, the ECU 20 determines that the fuel pump 30 or the brushless motor 32 is abnormal in step S1710. At this time, as shown in FIG. 27, the ECU 20 warns of an abnormality of the fuel pump 30 via a warning means (S1722).

  As described above, the processing flow shown in FIG. 27 is a modification of the third embodiment of the abnormality detection based on the remaining fuel amount shown in FIG. 24. Step S1721 and step S1710 warn of the lack of gas following step S1709. Subsequent to this, step S1722 for warning the abnormality of the fuel pump 30 is included.

  As described above with reference to FIGS. 25 to 27, when the ECU 20 detects a gas shortage or an abnormality in the fuel pump 30, the ECU 20 prompts the vehicle occupant to recognize the abnormality via a warning means. Therefore, an abnormality can be detected at an early stage, and safety measures can be taken promptly.

5. Ensuring safety when an abnormality is detected (2)
In the first embodiment, the second embodiment, or the third embodiment of the abnormality detection based on the remaining amount of fuel as described above, when a gas shortage in the fuel tank 70 or an abnormality in the fuel pump 30 or the brushless motor 32 is detected. The ECU 20 can perform processing for ensuring safety. Hereinafter, ensuring safety of abnormality detection (2) will be described as a modification of the first embodiment of abnormality detection based on the remaining fuel amount shown in FIG. In the case of ensuring safety at the time of abnormality detection (2), the procedure up to detection of gas shortage in the fuel tank 70 or abnormality of the fuel pump 30 or the brushless motor 32 is as described with reference to FIG. Accordingly, only the differences from the embodiment described with reference to FIG. 22 will be described, and the same step numbers will be assigned to other procedures, and description thereof will be omitted. Note that the safety ensuring (2) at the time of abnormality detection can also be applied to the embodiments described with reference to FIGS.

  For example, in the first embodiment of abnormality detection based on the remaining fuel amount shown in FIG. 22, the ECU 20 determines that the fuel pump or the brushless motor 32 is abnormal in step S1507. At this time, as shown in FIG. 28, the ECU 20 warns the abnormality of the fuel pump 30 via the warning means (S1511). On the other hand, in the first embodiment of abnormality detection based on the remaining amount of fuel shown in FIG. 22, the ECU 20 determines that there is a lack of fuel in the fuel tank 70 in step S1508. At this time, as shown in FIG. 28, the ECU 20 transfers the fuel in the fuel tank 70.

  As shown in FIG. 29, the fuel tank 70 has a main tank 72 and a reservoir tank 73. The main tank 72 and the reservoir tank 73 are separated by a partition wall 74. The main tank 72 houses the fuel pump 30. The reservoir tank 73 is provided above the main tank 72 in the vertical direction. When the fuel tank 70 is filled with fuel and the fuel level is higher than the partition wall 74, the fuel level in the main tank 72 and the reservoir tank 73 is substantially the same. On the other hand, since the fuel pump 30 is accommodated in the main tank 72, the fuel pump 30 sucks the fuel stored in the main tank 72 and discharges it to the outside of the fuel tank 70. At this time, even if the liquid level of the fuel stored in the main tank 72 is lowered as the fuel is discharged, the reservoir tank 73 partitioned by the partition wall 74 has a position corresponding to the height of the partition wall 74. In this case, the fuel level is maintained. That is, even if the fuel in the main tank 72 decreases, a predetermined amount of fuel is stored in the reservoir tank 73.

  A connection passage 75 is provided between the main tank 72 and the reservoir tank 73. The connection passage 75 connects the bottom wall of the reservoir tank 73 and the side wall near the bottom wall of the main tank 72. The connection passage 75 is provided with an on-off valve portion 76 as on-off valve means. The on-off valve portion 76 opens and closes the connection passage 75 and interrupts the flow of fuel between the reservoir tank 73 and the main tank 72. As the on-off valve unit 76, for example, an arbitrary valve such as a cock driven by an actuator according to an instruction from the ECU 20 or an electromagnetic valve opened / closed according to an instruction from the ECU 20 can be applied.

  As described above, when it is determined in step S1508 shown in FIG. 28 that the ECU 20 is out of gas, the ECU 20 opens the connection passage 75 by the on-off valve portion 76 in step S1521, and transfers fuel from the reservoir tank 73 to the main tank 72. To do. As a result, the fuel stored in the reservoir tank 73 is supplied to the main tank 72, and the fuel pump 30 discharges the fuel to the outside. Therefore, even if the amount of fuel in the fuel tank 70 decreases, the operation of the vehicle can be continued.

(Other embodiments)
In the plurality of embodiments described above, a case where a single type of fuel such as gasoline is used has been described as an example. Therefore, the ROM 22 of the control devices 10 and 110 stores the relationship between the voltage B of the battery 14 and the reference rotational speed NP of the brushless motor 32 as well as the upper limit value NP0 + α and the lower limit value NP0−α in accordance with a single type of fuel. It is recorded. On the other hand, in recent years, examples of adding biological fuels to conventional fuels such as gasoline such as gasoline mixed with ethanol are increasing. Fuels other than gasoline, such as ethanol, differ from gasoline in properties such as viscosity and density, for example. In addition, the characteristics of the mixed fuel vary depending on the content of ethanol or the like. When the characteristics of the mixed fuel change, even if the voltage B of the battery 14 is constant, the reference rotational speed NP of the brushless motor 32 changes depending on the characteristics of the fuel. For example, when the content of ethanol having higher viscosity than gasoline increases, the load of the brushless motor 32 increases, and the reference rotational speed NP of the brushless motor 32 decreases even when the voltage B of the battery 14 is constant. Therefore, the ECU 20 may correct the relationship between the voltage B of the battery 14 recorded in the ROM 22 of the control devices 10 and 110 and the reference rotational speed NP of the brushless motor 32 according to the type of fuel. That is, the ECU 20 functions as a correction unit that corrects the relationship between the voltage B and the reference rotational speed NP depending on the type of fuel.

  When correcting the relationship, the ECU 20 applies a specific voltage from the battery 14 to the brushless motor 32 prior to detecting the abnormality. The concentration of ethanol or the like contained in the fuel is estimated from the relationship between the specific voltage and the rotation speed of the brushless motor 32. As described above, the reference rotational speed NP of the brushless motor 32 decreases as the concentration of the fuel having high viscosity and density increases as long as the voltage B of the battery 14 is constant. From changes in these relationships, the ECU 20 estimates the concentration of ethanol or the like contained in the fuel. Then, the ECU 20 corrects the reference rotational speed NP recorded in the ROM 22 based on the estimated concentration of ethanol or the like.

As described above, by correcting the relationship between the voltage B of the battery 14 and the reference rotational speed NP of the brushless motor 32 according to the fuel to be used, the abnormality of the brushless motor 32 and the fuel pump 30 regardless of the type of fuel. Can be detected early and reliably.
Further, in the second embodiment of the fuel pump control device described above, when an abnormality is detected in the fuel pump 30 or the brushless motor 32, or when a gas shortage is detected, a warning or fuel by a warning means is provided to ensure safety. The transfer of fuel in the tank 70 has been described as an example. However, if an abnormality is detected in the fuel pump 30 or the brushless motor 32 in the second embodiment of the fuel pump control device, the fuel pump 30 is restarted, as in the first embodiment of the fuel pump control device, or It is also possible to perform control to change the fuel injection amount or the ignition timing as the fuel discharge pressure is reduced due to repeated forward rotation or reverse rotation or restart.

  As described above, the present invention is not limited to the above embodiment, and can be applied to various embodiments without departing from the scope of the invention.

The block diagram which shows the engine system to which the control apparatus of the fuel pump by 1st Embodiment of this invention is applied. 1 is a cross-sectional view schematically showing a fuel pump applied to a fuel pump control apparatus according to a first embodiment of the present invention. The schematic diagram which shows the relationship between the battery voltage and rotation speed of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 1st Embodiment of abnormality detection of the fuel pump by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 2nd Embodiment of abnormality detection of the fuel pump by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 1st Embodiment of the abnormal return of the fuel pump by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 2nd Embodiment of the abnormal return of the fuel pump by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of the 1st return mode routine in 2nd Embodiment of the abnormal return of the fuel pump by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of the 2nd return mode routine in 2nd Embodiment of the abnormal return of the fuel pump by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 1st Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 2nd Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 3rd Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 4th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 5th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 6th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 7th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the flow of 8th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the relationship between CFPF and (rho) set in 8th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the relationship between CFPF and (sigma) set in 8th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. Schematic which shows the relationship between CFPF and (kappa) set in 8th Embodiment of safety ensuring by the control apparatus of the fuel pump by 1st Embodiment of this invention. The block diagram which shows the engine system to which the control apparatus of the fuel pump by 2nd Embodiment of this invention is applied. Schematic which shows the flow of 1st Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. Schematic which shows the flow of 2nd Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. Schematic which shows the flow of 3rd Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. Schematic which shows the flow of safety ensuring (1) of 1st Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. Schematic which shows the flow of safety ensuring (1) of 2nd Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. Schematic which shows the flow of safety ensuring (1) of 3rd Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. Schematic which shows the flow of safety ensuring (2) of 1st Embodiment of the abnormality detection based on the residual amount of fuel by the control apparatus of the fuel pump by 2nd Embodiment of this invention. The schematic sectional drawing which shows the fuel tank applied to the control apparatus of the fuel pump by 2nd Embodiment of this invention.

Explanation of symbols

  10, 110: Control device, 13: Revolution detector (revolution detector), 14: Battery (power source), 20: ECU (abnormality detector, restarter, characteristic adjuster, corrector), 22: ROM (Storage means), 24: voltage detection unit (voltage detection unit), 30: fuel pump, 32: brushless motor, 62: injector control unit (characteristic adjustment unit), 63: ignition timing control unit (characteristic adjustment unit), 70 : Fuel tank, 71: Liquid level sensor, 72: Main tank, 73: Reservoir tank, 74: Bulkhead, 75: Connection passage, 76: Open / close valve

Claims (21)

A fuel pump control device that is driven by a brushless motor whose rotational speed is determined by the voltage of a power source and pressurizes and discharges fuel stored in a fuel tank,
Storage means for storing the relationship between the voltage of the power source and the rotation speed of the brushless motor;
Voltage detection means for detecting the voltage of the power source;
A rotational speed detection means for detecting the rotational speed of the brushless motor;
It is determined whether the rotation speed of the brushless motor detected by the rotation speed detection means and the voltage of the power source detected by the voltage detection means are within a predetermined range stored in the storage means. An abnormality detection means for determining that the fuel pump is abnormal when out of range;
A fuel pump control device comprising:   The fuel pump control device according to claim 1, further comprising restarting means for temporarily stopping and restarting the brushless motor when the abnormality detecting means detects an abnormality of the fuel pump.   3. The fuel pump according to claim 2, further comprising a characteristic adjusting unit that adjusts at least one of an injection amount of fuel and an ignition timing in an internal combustion engine supplied with fuel from the fuel tank when the fuel pump is stopped. Control device. A fuel pump control device that is driven by a brushless motor whose rotational speed is determined by the voltage of a power source and pressurizes and discharges fuel stored in a fuel tank,
Storage means for storing the relationship between the voltage of the power source and the rotation speed of the brushless motor;
Voltage detection means for detecting the voltage of the power source;
A rotational speed detection means for detecting the rotational speed of the brushless motor;
It is determined whether the rotation speed of the brushless motor detected by the rotation speed detection means and the voltage of the power source detected by the voltage detection means are within a predetermined range stored in the storage means. An abnormality detection means for determining that the fuel pump is abnormal when out of range;
When the abnormality detection means detects an abnormality of the fuel pump, restart means for temporarily stopping and restarting the brushless motor;
A fuel pump control device comprising: A fuel pump control device that is driven by a brushless motor whose rotational speed is determined by the voltage of a power source and pressurizes and discharges fuel stored in a fuel tank,
Storage means for storing the relationship between the voltage of the power source and the rotation speed of the brushless motor;
Voltage detection means for detecting the voltage of the power source;
A rotational speed detection means for detecting the rotational speed of the brushless motor;
It is determined whether the rotation speed of the brushless motor detected by the rotation speed detection means and the voltage of the power source detected by the voltage detection means are within a predetermined range stored in the storage means. An abnormality detection means for determining that the fuel pump is abnormal when out of range;
A characteristic adjusting means for adjusting at least one of a fuel injection amount and an ignition timing in an internal combustion engine supplied with fuel from the fuel tank when an abnormality of the fuel pump is detected;
A fuel pump control device comprising: A fuel pump control device that is driven by a brushless motor whose rotational speed is determined by the voltage of a power source and pressurizes and discharges fuel stored in a fuel tank,
Storage means for storing the relationship between the voltage of the power source and the rotation speed of the brushless motor;
Voltage detection means for detecting the voltage of the power source;
A rotational speed detection means for detecting the rotational speed of the brushless motor;
It is determined whether the rotation speed of the brushless motor detected by the rotation speed detection means and the voltage of the power source detected by the voltage detection means are within a predetermined range stored in the storage means. An abnormality detection means for determining that the fuel pump is abnormal when out of range;
When the abnormality detection means detects an abnormality of the fuel pump, restart means for temporarily stopping and restarting the brushless motor;
Characteristic adjusting means for adjusting at least one of the fuel injection amount and the ignition timing in the internal combustion engine to which fuel is supplied from the fuel tank when the brushless motor is stopped;
A fuel pump control device comprising:   The fuel pump control device according to claim 3, 5 or 6, wherein the characteristic adjusting means extends an injection period of fuel injected into the internal combustion engine when the brushless motor is stopped.   8. The fuel pump control device according to claim 7, wherein the characteristic adjusting means extends the injection period of the fuel injected into the internal combustion engine as the stop period of the brushless motor becomes longer.   7. The fuel pump control device according to claim 3, wherein the characteristic adjusting means increases an injection amount of fuel injected into the internal combustion engine when the brushless motor is stopped.   The fuel pump control device according to claim 9, wherein the characteristic adjusting unit increases an injection amount of fuel injected into the internal combustion engine as a stop period of the brushless motor becomes longer.   7. The fuel pump control device according to claim 3, wherein the characteristic adjusting means corrects the ignition timing of the internal combustion engine to an advance side when the brushless motor is stopped.   12. The fuel pump control device according to claim 11, wherein the characteristic adjusting means increases the correction amount of the ignition timing of the internal combustion engine to the advance side as the stop period of the brushless motor becomes longer. A fuel pump control device that is driven by a brushless motor whose rotational speed is determined by the voltage of a power source and pressurizes and discharges fuel stored in a fuel tank,
Storage means for storing the relationship between the voltage of the power source and the rotation speed of the brushless motor;
Voltage detection means for detecting the voltage of the power source;
A rotational speed detection means for detecting the rotational speed of the brushless motor;
It is determined whether the rotation speed of the brushless motor detected by the rotation speed detection means and the voltage of the power source detected by the voltage detection means are within a predetermined range stored in the storage means. When out of range, an abnormality detection means for determining whether there is an abnormality in the fuel pump based on the remaining amount of fuel in the fuel tank in which the fuel pump is housed,
A fuel pump control device comprising: A fuel remaining amount detecting means for detecting the remaining amount of fuel in the fuel tank;
14. The fuel pump control device according to claim 13, wherein when the remaining amount of fuel in the fuel tank detected by the remaining fuel amount detecting unit is smaller than a predetermined value, the abnormality detecting unit determines that the gas is out of gas.   The abnormality detection means detects the abnormality of the fuel pump based on the number of times that the rotation speed of the brushless motor and the voltage of the power source are outside a predetermined range stored in the storage means within a preset setting period. The fuel pump control device according to claim 13 or 14, wherein   When the number of times that the rotation speed of the brushless motor and the voltage of the power source are outside the predetermined range stored in the storage means is greater than a predetermined value within the set period, the abnormality detection means 16. The fuel pump control device according to claim 15, wherein the control is performed.   The fuel pump control device according to claim 14 or 16, further comprising warning means for issuing a warning when the abnormality detection means determines that the gas is in a shortage state. The fuel tank has a main tank in which the fuel pump is accommodated, and a reservoir tank partitioned from the main tank,
An opening / closing valve means for opening and closing a connection passage connecting the reservoir tank and the main tank;
17. The fuel pump according to claim 14, wherein, when the abnormality detection unit determines that there is a gas shortage, the on / off valve unit opens the connection passage and supplies fuel stored in the reservoir tank to the main tank. Control device.   The fuel pump control device according to claim 13 or 15, further comprising restarting means for temporarily stopping and restarting the brushless motor when the abnormality detecting means detects an abnormality of the fuel pump.   20. The fuel pump according to claim 19, further comprising characteristic adjusting means for adjusting at least one of a fuel injection amount and an ignition timing in an internal combustion engine supplied with fuel from the fuel tank when the fuel pump is stopped. Control device.   The correction means for correcting the relationship between the voltage of the power source stored in the storage means and the rotation speed of the brushless motor according to the characteristics of the fuel used. Fuel pump control device.

Images