Internal combustion engine control device

Abstract

To provide an internal combustion engine control device capable of improving injection accuracy of a fuel injection valve.SOLUTION: The engine control device 150 includes the drive circuit 157 that switches between the energized state and the non-energized state of the solenoid coil 13b that opens and closes the injector 13, and the microcomputer 152, the electric signal indicating that the application voltage applied to the solenoid coil 153a has reached the timing of executing the interruption processing is input to input port 13b, and the microcomputer 152 derives the valve-opening response delay length with respect to the valve-opening command based on the electric signal input to input port 153a while the valve-opening command for opening the injector 13 is being outputted to the drive circuit 157. The valve-opening response delay length is a length of time from when the microcomputer 152 outputs the valve-opening command to when the application voltage reaches a predetermined value while increasing, and the application voltage is detected based on the current supplied to the solenoid coil 13b.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an internal combustion engine control device. [Background technology]

[0002] In recent years, fuel injection valves have been adopted for internal combustion engines to improve power performance, etc., and in connection with demands for improved exhaust gas performance, etc., there is a demand for improving the injection accuracy of fuel injection valves.

[0003] Patent Document 1 discloses a configuration in which an ECU that performs fuel injection control of an internal combustion engine is provided with a drive circuit that supplies a drive current to a fuel injection valve, and a CPU that receives an output signal from a rotation angle sensor via an input port and outputs a control signal to the drive circuit via an output port. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-189410 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1, there is room for improvement in terms of improving the injection accuracy of the fuel injection valve.

[0006] An object of the present invention is to provide an internal combustion engine control device that can improve the injection accuracy of a fuel injection valve. [Means for solving the problem]

[0007] In order to achieve the above object, in one aspect, the present invention includes an electrical circuit that switches between an energized state and a de-energized state of an actuator that opens and closes a fuel injection valve of an internal combustion engine, and a microcomputer having an external interrupt port, wherein an electrical signal indicating that an applied voltage to the actuator has reached the timing to execute interrupt processing is input to the external interrupt port, and the microcomputer outputs a valve open command to the electrical circuit to open the fuel injection valve, and derives a valve opening response delay length in response to the valve open command when the fuel injection valve opens based on the electrical signal input to the external interrupt port while the valve open command is being output, the valve opening response delay length being the length of time from the time the microcomputer outputs the valve open command to the time when the applied voltage increases and reaches a predetermined threshold, and the applied voltage is detected based on the current passed through the actuator. [Effects of the Invention]

[0008] According to one aspect of the present invention, an internal combustion engine control device includes an electric circuit that switches between an energized state and a de-energized state of an actuator that opens and closes a fuel injection valve of an internal combustion engine, and a microcomputer having an external interrupt port, wherein an electric signal indicating that the applied voltage to the actuator has reached the timing to execute interrupt processing is input to the external interrupt port, and the microcomputer outputs a valve open command to the electric circuit to open the fuel injection valve, and derives a valve opening response delay length in response to the valve open command when the fuel injection valve opens based on the electric signal input to the external interrupt port while the valve open command is being output, wherein the valve opening response delay length is the length of time from the time the microcomputer outputs the valve open command to the time when the applied voltage increases and reaches a predetermined threshold, and the applied voltage is detected based on the current passed through the actuator, thereby improving the injection accuracy of the fuel injection valve. [Brief explanation of the drawings]

[0009] [Figure 1]FIG. 1 is a schematic diagram showing the configuration of an internal combustion engine control device according to an embodiment of the present invention together with an internal combustion engine. [Figure 2] FIG. 2 is a circuit diagram of an input circuit of the internal combustion engine control device according to the embodiment of the present invention. [Figure 3] FIG. 3 is a flowchart of a valve-opening response delay length calculation process executed by the internal combustion engine control device according to the embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart of a valve closing response delay length calculation process executed by the internal combustion engine control device according to the embodiment of the present invention. [Figure 5] FIG. 5 is a flowchart of the command output timing correction process executed by the internal combustion engine control device according to the embodiment of the present invention. [Figure 6] FIG. 6 is a timing chart showing the operation of the internal combustion engine control device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an internal combustion engine control device according to an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

[0011] <Engine configuration> The configuration of an engine 1 to which an internal combustion engine control device 150 according to an embodiment of the present invention is applied will be described in detail with reference to FIG.

[0012] The engine 1 is a four-stroke reciprocating internal combustion engine mounted on a vehicle such as a motorcycle (not shown) equipped with a battery Bt. The engine 1 has a cylinder block 2 and its operating state is controlled by an internal combustion engine control device 150. While the engine 1 is shown in the figure as having a single cylinder 2a for ease of explanation, the engine 1 may have multiple cylinders 2a, and the cylinders 2a may be arranged in an in-line, horizontally opposed, or V-type configuration. The engine 1 is water-cooled, and a coolant passage 3 provided in the side wall of the cylinder block 2 is provided with a water temperature sensor 101 for detecting the temperature of the coolant flowing through the coolant passage 3. The water temperature sensor 101 outputs an electrical signal indicating the temperature of the coolant to the internal combustion engine control device 150. The engine 1 is not limited to being water-cooled, but may also be air-cooled. If the engine 1 is air-cooled, a temperature sensor for detecting the temperature of the engine 1 is provided in the cylinder block 2 or the like instead of the water temperature sensor 101.

[0013] A piston 4 is disposed inside the cylinder block 2. The piston 4 is connected to a crankshaft 6 via a connecting rod 5. A reluctor 7 is provided on the crankshaft 6, which rotates coaxially with the crankshaft 6. A plurality of teeth 7a are provided on the outer peripheral surface of the reluctor 7, and are arranged side by side in a predetermined pattern in the circumferential direction. A crank angle sensor 102 is provided near the plurality of teeth 7a in a lower case (not shown) or the like attached to the bottom of the cylinder block 2 to detect the rotational angle of the crankshaft 6 so that the internal combustion engine control device 150 can detect the rotational speed of the engine 1. The crank angle sensor 102 outputs an electrical signal indicating the rotational angle of the crankshaft 6 to the internal combustion engine control device 150.

[0014] A cylinder head 8 is attached to the top of the cylinder block 2. The internal space defined by the inner wall surface of the cylinder block 2, the upper surface of the piston 4, and the inner wall surface of the cylinder head 8 cooperates to form a combustion chamber 9.

[0015] The cylinder block 2 and the cylinder head 8 are provided with a spark plug 10 for each cylinder 2a, which ignites an air-fuel mixture produced from fuel and air in a combustion chamber 9. The ignition operation of the spark plug 10 is controlled by an internal combustion engine control device 150, which controls the supply of electricity to an ignition coil (not shown).

[0016] The cylinder head 8 is provided with an intake valve 12 that freely opens and closes communication between the combustion chamber 9 and an intake passage 11a formed in the cylinder head 8 and an intake pipe 11 attached to the cylinder head 8. The intake pipe 11 is provided with a fuel injection valve 13 that injects fuel into the intake passage 11a, and a throttle valve 14a that is located upstream of the fuel injection valve 13 and is a component of a throttle device 14. The intake pipe 11 is also provided with an intake pressure sensor 103 between the intake valve 12 and the throttle valve 14a that detects the pressure (intake pressure) of air flowing into the intake pipe 11. The intake pressure sensor 103 outputs an electric signal indicating a voltage corresponding to the intake pressure to the internal combustion engine control device 150. A throttle opening sensor 104 that detects the opening of the throttle valve 14a is attached to the main body of the throttle device 14 or the like. The throttle opening sensor 104 outputs an electric signal indicating a voltage corresponding to the opening of the throttle valve 14a (throttle opening) to the internal combustion engine control device 150. The fuel injection valve 13 mainly has a valve element 13a, a solenoid coil 13b which is an actuator, and a plunger (not shown) which moves the valve element 13a by receiving a magnetic force from the solenoid coil 13b, and the opening and closing operations of the valve element 13a via the plunger are controlled by the internal combustion engine control device 150 by controlling the supply of electricity to the solenoid coil 13b.

[0017] An exhaust pipe 15 is attached to the cylinder head 8 on the opposite side of the intake pipe 11, and an exhaust passage 15a communicating with the combustion chamber 9 is formed in the cylinder head 8 and in the exhaust pipe 15. The cylinder head 8 is also provided with an exhaust valve 16 that freely opens and closes communication between the combustion chamber 9 and the exhaust passage 15a. A catalyst 17, which is a three-way catalyst that purifies exhaust gas discharged from the combustion chamber 9, is provided in the exhaust pipe 15 downstream of the exhaust valve 16, and an O2 sensor 105 that detects the oxygen concentration in the exhaust gas is provided upstream of and adjacent to the catalyst 17. The O2 sensor 105 outputs an electrical signal indicating a voltage corresponding to the oxygen concentration in the exhaust gas upstream of the catalyst 17 to an internal combustion engine control device 150.

[0018] An accelerator opening sensor 106 is attached to a steering wheel or the like (not shown) of the vehicle. The accelerator opening sensor 108 detects the amount of operation (accelerator opening) of an accelerator grip or the like, which is an accelerator operating member (not shown) of the vehicle, and outputs an electric signal indicating a voltage corresponding to the detected accelerator opening to the internal combustion engine control device 150. The voltage of a battery Bt mounted on the vehicle is detected by a voltage sensor 107. The voltage sensor 107 outputs an electric signal indicating the voltage of the battery Bt to the internal combustion engine control device 150.

[0019] <Configuration of the internal combustion engine control device> The configuration of an internal combustion engine control device 150 according to an embodiment of the present invention will be described in detail with reference to FIGS.

[0020] Note that an electrical connection may be simply referred to as a connection, and the potential difference between the potential of a certain part and the ground potential may be referred to as the voltage at that part. In addition, in input circuit 158, the upstream side refers to the fuel injector 13 side, and the downstream side refers to the microcomputer 152 side.

[0021] The internal combustion engine control device 150 is configured by an ECU (Electronic Control Unit), which is an electronic control device mounted on a vehicle and controls the operation of the engine 1.

[0022] The internal combustion engine control device 150 is an arithmetic processing device including a microcomputer 152 having an input port 153 and an output port 154. The input port 153 is an external interrupt port to which an external signal for interrupt processing is input. The internal combustion engine control device 150 also includes a waveform shaping circuit 155 which is an electric circuit that shapes the waveform of an electric signal input from the crank angle sensor 102, an A / D conversion circuit 156 which is an electric circuit that A / D converts electric signals from the water temperature sensor 101, the intake pressure sensor 103, the throttle opening sensor 104, the O2 sensor 105, the accelerator opening sensor 106, and the voltage sensor 107, a drive circuit 157 which is an electric circuit that has a switching element such as a transistor and switches the solenoid coil 13b of the fuel injection valve 13 between an energized state and a non-energized state, and an input circuit 158 ​​to which a current to be applied to the solenoid coil 13b is input. The microcomputer 152 includes a CPU (Central Processing Unit), a memory that stores control programs and control data, and a timer, none of which are shown.

[0023] The drive circuit 157 is provided between the fuel injection valve 13 and the microcomputer 152, and is connected to the microcomputer 152 via an output port 154 of the microcomputer 152. When an ON signal (valve open command), which is a high-level electrical signal with a relatively high voltage, is input from the microcomputer 152 via the output port 154, the drive circuit 157 changes an internal switching element (not shown) from an OFF state to an ON state, thereby bringing the solenoid coil 13b of the fuel injection valve 13 into a conducting state in which current flows from the battery Bt to the solenoid coil 13b. On the other hand, when an OFF signal (valve close command), which is a low-level electrical signal with a relatively low voltage, is input from the microcomputer 152 via the output port 154, the drive circuit 157 changes an internal switching element from an ON state to an OFF state, thereby bringing the solenoid coil 13b of the fuel injection valve 13 into a non-conducting state in which current is blocked from flowing from the battery Bt to the solenoid coil 13b. The connection point P1 (see FIG. 2) is set to the low potential side end of the solenoid coil 13b via the connector 160, and the high potential side end of the solenoid coil 13b is connected to an IGP power supply that is connected to the battery Bt when an ignition switch (not shown) changes from an off state to an on state.

[0024] The input circuit 158 ​​includes an operational amplifier 161, an operational amplifier 162, an operational amplifier 163, a noise filter circuit F1, a noise filter circuit F2, a voltage detection circuit G1, and a switch circuit T1. A power supply voltage VCC is supplied to each of the operational amplifiers 161, 162, and 163.

[0025] The operational amplifier 161 is provided in a stage subsequent to the fuel injector 13 and the IGP power supply. The non-inverting input terminal of the operational amplifier 161 is connected to the fuel injector 13 via the connection point P5, the connection point P4, the noise filter circuit F1, the connection point P1, and the connector 160.

[0026] The noise filter circuit F1 includes resistors R1, R2, R3, and a capacitor C1. One terminal of the resistor R1 is connected to a connection point P1, and the other terminal of the resistor R1 is connected to a connection point P2. One terminal of the resistor R2 is connected to a connection point P2, and the other terminal of the resistor R2 is connected to a connection point P3. One terminal of the resistor R3 is connected to the connection point P3, and the other terminal of the resistor R3 is grounded. One terminal of the capacitor C1 is connected to the connection point P2, and the other terminal of the capacitor C1 is grounded.

[0027] Furthermore, diodes D1 and D2 are connected between the non-inverting input terminal of the operational amplifier 161 and the noise filter circuit F1. The anode terminal of diode D1 is connected to node P4, and the cathode terminal of diode D1 is connected to the IGP power supply. The anode terminal of diode D2 is grounded, and the cathode terminal of diode D2 is connected to node P5.

[0028] The inverting input terminal of the operational amplifier 161 is connected to the IGP power supply via the connection points P10, P9, P8 and the noise filter circuit F2.

[0029] The noise filter circuit F2 is a filter in phase with the noise filter circuit F1 and includes resistors R4, R5, R6, and a capacitor C2. The resistors R4, R5, and R6 are provided downstream of the IGP power supply. One terminal of the resistor R4 is connected to the IGP power supply, and the other terminal of the resistor R4 is connected to a connection point P6. One terminal of the resistor R5 is connected to the connection point P6, and the other terminal of the resistor R5 is connected to a connection point P7. One terminal of the resistor R6 is connected to the connection point P7, and the other terminal of the resistor R6 is grounded. One terminal of the capacitor C2 is connected to the connection point P6, and the other terminal of the capacitor C2 is grounded.

[0030] Furthermore, diodes D3 and D4 are connected between the inverting input terminal of the operational amplifier 161 and the noise filter circuit F2. The anode terminal of diode D3 is connected to node P9, and the cathode terminal of diode D3 is connected to the IGP power supply. The anode terminal of diode D4 is grounded, and the cathode terminal of diode D4 is connected to node P10.

[0031] The output terminal of the operational amplifier 161 is connected to the non-inverting input terminal of the operational amplifier 162 via connection points P11, P12, P13, a resistor R8, and P14. In addition, a diode D5, a diode D6, and a capacitor C3 are connected between the output terminal of the operational amplifier 161 and the non-inverting input terminal of the operational amplifier 162, respectively.

[0032] One terminal of resistor R8 is connected to node P13, and the other terminal of resistor R8 is connected to node P14. The anode terminal of diode D5 is connected to node P12. The cathode terminal of diode D5 is connected to the VCC power supply. The anode terminal of diode D6 is grounded. The cathode terminal of diode D6 is connected to node P13. One terminal of capacitor C3 is connected to node P14, and the other terminal of capacitor C3 is grounded.

[0033] Here, if the voltage value indicated by the electrical signal input to the non-inverting input terminal of the operational amplifier 161, which is obtained by dividing the voltage at the connection point P1 at the low potential end of the solenoid coil 13b by the resistance division between the combined resistance of the resistance elements R1 and R2 and the resistance of the resistance element R3, is equal to or greater than the reference voltage value obtained by dividing the voltage of the IGP power supply by the resistance division between the combined resistance of the resistance elements R5 and R6 and the resistance of the resistance element R6, then a high level electrical signal indicating a relatively high voltage is output from the output terminal of the operational amplifier 161. On the other hand, when the voltage value indicated by the electrical signal input to the non-inverting input terminal of the operational amplifier 161, which is obtained by dividing the voltage at the connection point P1 at the low-potential end of the solenoid coil 13b by the resistance division between the combined resistance of the resistor elements R1 and R2 and the resistance of the resistor element R3, is less than the reference voltage obtained by dividing the voltage of the IGP power supply by the resistance division between the combined resistance of the resistor elements R5 and R6 and the resistance of the resistor element R6, a low-level electrical signal indicating a relatively low voltage is output from the output terminal of the operational amplifier 161. In other words, the electrical signal thus output indicates a high-level voltage when the input voltage from the connection point P1 side, i.e., the solenoid coil 13b side, is equal to or greater than the threshold voltage, with the reference voltage being the divided voltage obtained by dividing the voltage of the IGP power supply by the resistance division between the combined resistance of the resistor elements R5 and R6 and the resistance of the resistor element R6 as the threshold voltage, and indicates a low-level voltage when the input voltage from the connection point P1 side, i.e., the solenoid coil 13b side, is less than the threshold voltage. Therefore, the magnitude of the output voltage output from the output terminal of the operational amplifier 161 is equal to or greater than a predetermined value corresponding to the threshold voltage. Note that the operational amplifier 161, the noise filter circuit F1, and the noise filter circuit F2 may be omitted as necessary.

[0034] The non-inverting input terminal of the operational amplifier 162 is connected to the output terminal of the operational amplifier 161 via connection point P14, resistor R8, connection point P13, connection point P12, and connection point P11, and is also connected to the noise filter circuit F2 via connection point P14, resistor R8, connection point P13, connection point P12, connection point P11, resistor R7, and connection point P8. The inverting input terminal of the operational amplifier 162 is connected to the power supply voltage VCC via connection point P15 and resistor R9. The output terminal of the operational amplifier 162 is connected to the input port 153b of the microcomputer 152 via connection point P17, resistor R13, and connection point P18. In addition, resistor R12 and capacitor C4 are connected between the output terminal of the operational amplifier 162 and the input port 153b of the microcomputer 152, respectively.

[0035] One terminal of resistor R7 is connected to node P11 between the output terminal of operational amplifier 161 and node P12, and the other terminal of resistor R7 is connected to node P8 between node P7 and resistor R7. One terminal of resistor R12 is connected to node P17, and the other terminal of resistor R12 is connected to the VCC power supply. One terminal of resistor R13 is connected to node P17, and the other terminal of resistor R13 is connected to node P18. One terminal of capacitor C4 is connected to node P18, and the other terminal of capacitor C4 is grounded.

[0036] The non-inverting input terminal of the operational amplifier 163 is connected to the fuel injector 13 via a connection point P27, a resistor R19, a connection point P26, a connection point P25, a voltage detection circuit G1, a switch circuit T1, a connection point P1, and a connector 160. The inverting input terminal of the operational amplifier 163 is connected to a power supply voltage VCC via a connection point P16, a resistor R10, a connection point P15, and a resistor R9. The output terminal of the operational amplifier 163 is connected to an input port 153a of the microcomputer 152 via a connection point P28, a resistor R21, and a connection point P29. A diode D7, a resistor R19, and a capacitor C6 are connected between the voltage detection circuit G1 and the operational amplifier 163, respectively, and a resistor R20 and a capacitor C7 are connected between the output terminal of the operational amplifier 163 and the input port 153a of the microcomputer 152, respectively.

[0037] One terminal of resistor R19 is connected to node P27, and the other terminal of resistor R19 is connected to node P26. One terminal of resistor R20 is connected to node P28, and the other terminal of resistor R20 is connected to the VCC power supply. One terminal of resistor R21 is connected to node P28, and the other terminal of resistor R21 is connected to node P29. The anode terminal of diode D7 is connected to node P26, and the cathode terminal of diode D7 is connected to the VCC power supply. One terminal of capacitor C7 is connected to node P29, and the other terminal of capacitor C7 is grounded.

[0038] The voltage detection circuit G1 is provided downstream of the fuel injector 13 and the IGP power supply. The voltage detection circuit G1 is connected to the fuel injector 13 via a switch circuit T1 and a connector 160. The voltage detection circuit G1 includes an operational amplifier 164, a shunt resistor R14, resistor elements R15, R16, R17, and R18, and a capacitor C5. The non-inverting input terminal of the operational amplifier 164 is connected to one terminal P19 of the shunt resistor R14 via a connection point P22, a connection point P21, and the resistor element R15, and is also connected to a connection point P23 via the capacitor C5. The inverting input terminal of the operational amplifier 164 is connected to the other terminal P20 of the shunt resistor R14 via a connection point P23, a connection point P24, and the resistor element R16, and is also connected to a connection point P22 via the capacitor C5. The output terminal of the operational amplifier 164 is connected to the non-inverting input terminal of the operational amplifier 163 via a connection point P25, a connection point P26, a resistor R19, and a connection point P27. One terminal P19 of the shunt resistor R14 is connected to the fuel injector 13 via the switch circuit T1, the connection point P1, and the connector 160, and the other terminal P20 of the shunt resistor R14 is grounded. The operational amplifier 164 is supplied with a power supply voltage VCC.

[0039] One terminal of resistor R15 is connected to one terminal P19 of shunt resistor R14, and the other terminal of resistor R15 is connected to node P21. One terminal of resistor R16 is connected to the other terminal P20 of shunt resistor R14, and the other terminal of resistor R16 is connected to node P24. One terminal of resistor R17 is connected to node P21, and the other terminal of resistor R17 is grounded. One terminal of resistor R18 is connected to node P24, and the other terminal of resistor R18 is connected to node P25 between voltage detection circuit G1 and node P26. One terminal of capacitor C5 is connected to node P22, and the other terminal of capacitor C5 is connected to node P23.

[0040] In the voltage detection circuit G1 having the above configuration, when the switch circuit T1 is in a connected state, a current flowing through the solenoid coil 13b flows through the shunt resistor R14. The operational amplifier 164 detects the voltage between one terminal P19 of the shunt resistor R14, which is connected to the non-inverting input terminal of the operational amplifier 164, and the other terminal P20, which is connected to the inverting input terminal of the operational amplifier 164, as the voltage applied to the solenoid coil 13b, and amplifies the detected terminal voltage and outputs it from the output terminal. In this way, the voltage applied to the solenoid coil 13b is detected by the operational amplifier 164 as the current flowing through the solenoid coil 13b flows through the shunt resistor R14, and is amplified by the operational amplifier 164 as an amplifier.

[0041] Here, when the voltage value indicated by the electrical signal output from the output terminal of the operational amplifier 161 and input to the non-inverting input terminal of the operational amplifier 162 is equal to or greater than the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance of the resistor element R9 and the combined resistance of the resistor elements R10 and R11, a high-level electrical signal Joff indicating a relatively high voltage is output from the output terminal of the operational amplifier 162. On the other hand, when the voltage value indicated by the electrical signal output from the output terminal of the operational amplifier 161 and input to the non-inverting input terminal of the operational amplifier 162 is less than the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance of the resistor element R9 and the combined resistance of the resistor elements R10 and R11, a low-level electrical signal Joff indicating a relatively low voltage is output.

[0042] Furthermore, when the voltage value indicated by the electrical signal output from the output terminal of the operational amplifier 164 and input to the non-inverting input terminal of the operational amplifier 163 is equal to or greater than the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance division of the combined resistance of the resistor elements R9 and R10 and the resistance of the resistor element R11, a high-level electrical signal Jon indicating a relatively high voltage is output from the output terminal of the operational amplifier 163. On the other hand, when the voltage value indicated by the electrical signal output from the output terminal of the operational amplifier 164 and input to the non-inverting input terminal of the operational amplifier 163 is less than the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance division of the combined resistance of the resistor elements R9 and R10 and the resistance of the resistor element R11, a low-level electrical signal Jon indicating a relatively low voltage is output.

[0043] The resistances of resistors R1 and R4 are set equal to each other. The resistances of resistors R2 and R5 are set equal to each other. The resistances of resistors R8, R13, R19, and R21 are set equal to each other. The resistances of resistors R3, R6, R15, and R16 are set equal to each other. The resistance of shunt resistor R14 is set smaller than the resistances of resistors R1 through R13 and resistors R15 through R21.

[0044] Furthermore, the capacitances of capacitors C1 and C2 are set to be equal to each other. The capacitances of capacitors C3 and C6 are set to be equal to each other. The capacitances of capacitors C4 and C7 are set to be equal to each other. The capacitance of capacitor C5 is set to be smaller than the capacitances of capacitors C1 to C4, C6, and C7.

[0045] The switch circuit T1 opens and closes when driven by the drive circuit 157, thereby connecting or disconnecting the fuel injector 13 and the voltage detection circuit G1 via the connector 160. Specifically, when an ON signal (valve open command), which is a high-level electrical signal with a relatively high voltage, is input from the microcomputer 152 to the drive circuit 157, the switch circuit T1 drives the drive circuit 157 to connect the fuel injector 13 and the voltage detection circuit G1 via the connector 160. On the other hand, when an OFF signal (valve close command), which is a low-level electrical signal with a relatively low voltage, is input from the microcomputer 152 to the drive circuit 157, the switch circuit T1 drives the drive circuit 157 to disconnect the fuel injector 13 and the voltage detection circuit G1.

[0046] The internal combustion engine control device 150 controls the operation of the various control objects such as the spark plug 10 and the fuel injection valve 13 by executing a control and processing program read from memory based on input signals from various sensors acquired via a waveform shaping circuit 155, an A / D conversion circuit 156, an input circuit 158, etc., and necessary control and processing data read from a memory not shown, thereby controlling the operating state of the engine 1.

[0047] Furthermore, the internal combustion engine control device 150 includes a drive circuit 157, which is an electrical circuit that switches between an energized state and an unenergized state of the solenoid coil 13b, which is an actuator that drives the valve body 13a of the fuel injection valve 13, and a microcomputer 152 having input ports 153 (153a, 153b), which are external interrupt ports to which an external electrical signal indicating the voltage applied to the solenoid coil 13b and applied for interrupt processing is input, and an electrical signal indicating that the voltage applied to the solenoid coil 13b has reached the timing to perform interrupt processing is input to the input ports 153 (153a, 153b), which are external interrupt ports.

[0048] The internal combustion engine control device 150 having the above configuration executes, as interrupt processes, a valve opening response delay length calculation process that calculates a valve opening response delay length with respect to a valve opening command output to the drive circuit 157, a valve closing response delay length calculation process that calculates a valve closing response delay length with respect to a valve closing command output to the drive circuit 157, and a command output timing correction process that corrects the output timing of a valve opening command or a valve closing command output to the drive circuit 157 that drives the fuel injector 13. Each of the above processes executed by the internal combustion engine control device 150 will be described in detail below with further reference to Figures 3 to 6.

[0049] <Calculation process for valve opening response delay length> The valve-opening response delay length calculation process executed by the internal combustion engine control device 150 according to the embodiment of the present invention will be described in detail with reference to FIGS.

[0050] In Figure 6, the "open / close valve command (CINJ)" is a valve open command or valve close command indicated by an electrical signal output from output port 154 of microcomputer 152 to drive circuit 157, the "voltage converted from the current passed through solenoid coil 13b" indicates the voltage value of the electrical signal output from the output terminal of operational amplifier 164 and input to the non-inverting input terminal of operational amplifier 163, the "input voltage to input port 153a" indicates the voltage value of electrical signal JOn output from the output terminal of operational amplifier 163 and input to input port 153a of microcomputer 152, and the "input voltage to input port 153b" indicates the voltage value of electrical signal Joff output from the output terminal of operational amplifier 162 and input to input port 153b of microcomputer 152.

[0051] The valve opening response delay length calculation process shown in Fig. 3 starts when an ignition switch (not shown) is turned on from an off state to start the internal combustion engine control device 150, and the valve opening response delay length calculation process proceeds to the process of step S1. The valve opening response delay length calculation process shown in Fig. 3 is repeatedly executed at predetermined control intervals while the internal combustion engine control device 150 is in the start-up state.

[0052] In the process of step S1, the microcomputer 152 outputs an ON signal (valve open command), which is a high-level electrical signal, from the output port 154 to the drive circuit 157. This ends the process of step S1, and the valve-opening response delay length calculation process proceeds to the process of step S2.

[0053] In the process of step S2, the microcomputer 152 determines whether or not a valve-open command has been output from the output port 154 to the drive circuit 157. Specifically, if the voltage value of the valve-open command output in the process of step S1 is equal to or greater than a predetermined value, the microcomputer 152 determines that a valve-open command has been output, and advances the valve-opening response delay length calculation process to the process of step S3. On the other hand, if the voltage value of the valve-open command output in the process of step S1 is less than the predetermined value, the microcomputer 152 determines that a valve-open command has not been output, and repeats the process of step S2.

[0054] 6, at time t1, the microcomputer 152 outputs an ON signal (valve open command), which is a high-level electrical signal CINJ, from the output port 154 to the drive circuit 157, and the drive circuit 157 turns on the switch circuit T1, connecting the fuel injector 13 and the voltage detection circuit G1. Also at time t1, the solenoid coil 13b is energized, and a current begins to flow from the battery Bt side to the solenoid coil 13b. The current flowing through the solenoid coil 13b begins to flow through the switch circuit T1 to the shunt resistor R14. The voltage detection circuit G1 detects and amplifies the voltage between one terminal P19 and the other terminal P20 of the shunt resistor R14, which is generated by the current flowing through the shunt resistor R14, using the operational amplifier 164, and outputs the amplified voltage as the voltage applied to the solenoid coil 13b from the output terminal of the operational amplifier 164. At this time, a back electromotive force is generated in the solenoid coil 13b, causing the current flowing from the battery Bt to the solenoid coil 13b to gradually increase. Furthermore, a magnetic force begins to be applied to the plunger (not shown) of the fuel injector 13. The plunger, together with the valve element 13a attached thereto, begins to move against the biasing force of a spring (not shown), fuel pressure, frictional force, and other factors. The voltage applied to the solenoid coil 13b, i.e., the voltage at the connection point P1, gradually decreases from V1, which is derived from the voltage of the battery Bt. Furthermore, the current flowing through the shunt resistor R14 increases after time t1, and the voltage output from the operational amplifier 164 increases after time t1 and approaches the threshold value VT1. The period during which the valve open command is output and the solenoid coil 13b is energized is from time t1 to time t4, and the output of the valve open command begins at time t1.

[0055] In the process of step S3, the microcomputer 152 starts a first count process to count the elapsed time since the valve-open command was output from the output port 154 to the drive circuit 157. This completes the process of step S3, and the valve-open response delay length calculation process proceeds to the process of step S4. Note that the series of processes starting from the process of step S3 constitutes interrupt processing.

[0056] Here, as shown in FIG. 6, at time t1, the microcomputer 152 starts a first counting process of counting the elapsed time since an opening valve command is output from the output port 154 to the drive circuit 157.

[0057] In the process of step S4, the microcomputer 152 determines whether the value of the input voltage to the input port 153a, that is, the voltage value of the electrical signal JOn output from the output terminal of the operational amplifier 163 and input to the input port 153a, has become from VL1 or more to VH1 (VL1 < VH1) or less. As a result of the determination, when the voltage value of the electrical signal JOn has become from VL1 or more to VH1 or less, the microcomputer 152 advances the opening valve response delay length calculation process to the process of step S5. On the other hand, as a result of the determination, when the voltage value of the electrical signal JOn has not become from VL1 or more to VH1 or less, the microcomputer 152 repeats the process of step S4.

[0058] Here, as shown in FIG. 6, at time t2, the back electromotive voltage generated in the solenoid coil 13b disappears, a part of the valve body 13a abuts on a stopper (not shown), the valve body 13a and the plunger stop, the valve body 13a is maintained in the fully open state, the value of the voltage applied to the solenoid coil 13b reaches a constant value V2, and thereafter, until time t4, the constant value V2 is maintained. Further, as the current flowing through the shunt resistor R14 continues to increase after time t1, the voltage value indicated by the electrical signal output from the output terminal of the operational amplifier 164 and input to the non-inverting input terminal of the operational amplifier 163 gradually increases after time t1 and reaches the threshold value VT1 at time t3. Here, the threshold value VT1 is the value of the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance voltage division of the combined resistance of the resistance element R9 and the resistance element R10 and the resistance of the resistance element R11. Thereby, at time t3, the input voltage value of the electrical signal Jon output from the output terminal of the operational amplifier 163 and input to the input port 153a of the microcomputer 152 changes from VL1 to VH1. Here, the electrical signal Jon whose input voltage value has changed to VH1 is an electrical signal indicating that the timing for the operational amplifier 163 to execute the interruption process has arrived when the voltage applied to the solenoid coil 13b.

[0059] In the process of step S5, the microcomputer 152 stops the first counting process and calculates the first count value n1 counted by the first counting process as a valve-opening response delay length Ton, which is the time length of the valve-opening response delay in response to a valve-opening command when the valve body 13a of the fuel injector 13 opens. This completes the process of step S5, and the valve-opening response delay length calculation process proceeds to the process of step S6.

[0060] 6, at time t3, the first counting process is stopped and the count value reaches n1. Here, the valve-opening response delay length Ton is the length of time from time t1, when the valve-opening command is output, to time t3, when the count value reaches threshold value VT1 while increasing, as indicated by the voltage value indicated by the electrical signal output from the output terminal of operational amplifier 164 and input to the non-inverting input terminal of operational amplifier 163.

[0061] In the process of step S6, the microcomputer 152 calculates the difference between the valve-opening response delay length Ton calculated in the process of step S5 and a predetermined reference value as a first difference. This completes the process of step S6, and the valve-opening response delay length calculation process proceeds to the process of step S7.

[0062] In the process of step S7, microcomputer 152 uses the first difference value calculated in the process of step S6 and each of the first difference values ​​calculated from the first valve-opening response delay length calculation process after the current start of engine 1 to the previous valve-opening response delay length calculation process to calculate a first average value, which is the average value of each of the first difference values ​​calculated from the first valve-opening response delay length calculation process after the current start of engine 1 to the current valve-opening response delay length calculation process. This completes the process of step S7, and the valve-opening response delay length calculation process proceeds to the process of step S8.

[0063] In the process of step S8, the microcomputer 152 corrects the first average value calculated in the process of step S7 by the voltage of the battery Bt to calculate the corrected first average value FTon, and then the valve-opening response delay length calculation process is completed.

[0064] According to the above-described valve opening response delay length calculation process, the voltage detection circuit G1 converts the current flowing through the solenoid coil 13b, which gradually increases from time t1 to time t3, into a voltage, and executes interrupt processing at the timing of time t3 when the converted voltage value reaches VT1. This improves the time resolution of detection and improves the detection accuracy compared to when the interrupt processing is executed at the timing of time t2 when the voltage applied to the solenoid coil 13b reaches V2.

[0065] <Calculation process for valve closing response delay length> The valve closing response delay length calculation process executed by the internal combustion engine control device 150 according to the embodiment of the present invention will be described in detail with reference to FIGS.

[0066] The valve closing response delay length calculation process shown in Fig. 4 starts when an ignition switch (not shown) changes from an off state to an on state and the internal combustion engine control device 150 starts up, and the valve closing response delay length calculation process proceeds to the process of step S11. The valve closing response delay length calculation process shown in Fig. 4 is repeatedly executed at predetermined control intervals while the internal combustion engine control device 150 is in the start-up state.

[0067] In the process of step S11, the microcomputer 152 outputs an OFF signal (valve close command), which is a low-level electrical signal, from the output port 154 to the drive circuit 157. This ends the process of step S11, and the process of calculating the valve close response delay length proceeds to the process of step S12.

[0068] In the process of step S12, the microcomputer 152 determines whether a valve close command has been output from the output port 154 to the drive circuit 157. Specifically, if the voltage value of the valve close command output in the process of step S11 is less than a predetermined value, the microcomputer 152 determines that a valve close command has been output, and advances the valve close response delay length calculation process to the process of step S13. On the other hand, if the voltage value of the valve close command output in the process of step S11 is equal to or greater than the predetermined value, the microcomputer 152 determines that a valve close command has not been output, and repeats the process of step S12.

[0069] As shown in FIG. 6, at time t4, the microcomputer 152 outputs an OFF signal (valve close command) that is a low-level electrical signal CINJ from the output port 154 to the drive circuit 157. The voltage L of the valve close command is smaller than the predetermined value A. At time t4, the solenoid coil 13b is de-energized, and no current flows from the battery Bt to the solenoid coil 13b. At this time, a back electromotive force is generated in the solenoid coil 13b. The voltage applied to the solenoid coil 13b, i.e., the voltage at the connection point P1, increases from V2. Meanwhile, the magnetic force applied to the plunger disappears, and the plunger and valve element 13a begin to return to their initial positions under the biasing force of the spring alone. The period during which the valve close command is output and the solenoid coil 13b is de-energized is the period after time t4. The output of the valve close command begins at time t4.

[0070] In the process of step S13, the microcomputer 152 starts a second counting process of counting the elapsed time since the valve close command was output from the output port 154 to the drive circuit 157. This completes the process of step S13, and the valve close response delay length calculation process proceeds to the process of step S14. Note that the series of processes starting from the process of step S13 constitutes an interrupt process.

[0071] Here, as shown in FIG. 6, at time t4, the microcomputer 152 starts a second counting process for counting the elapsed time since a valve closing command is output from the output port 154 to the drive circuit 157.

[0072] In the process of step S14, the microcomputer 152 determines whether the value of the input voltage to the input port 153b, that is, the voltage value of the electrical signal JOff output from the output terminal of the operational amplifier 162 and input to the input port 153b, has changed from VH2 or more to VL2 (<VH2) or less. As a result of the determination, if the voltage value of the electrical signal JOff has changed from VH2 or more to VL2 or less, the microcomputer 152 advances the valve closing response delay length calculation process to the process of step S15. On the other hand, as a result of the determination, if the voltage value of the electrical signal JOff has not changed from VH2 or more to VL2 or less, the microcomputer 152 repeats the process of step S14.

[0073] 6, at time t9, the value of the input voltage to input port 153b changes from VH2 to VL2. At time t9, the value of the voltage applied to solenoid coil 13b of fuel injector 13, i.e., the value of the voltage at node P1, reaches threshold value VT2, which is a reference voltage obtained by dividing the voltage of the VCC power supply by the resistance of resistor R7 and the combined resistance of resistor elements R8 and R9. The valve close command, i.e., the voltage L, is maintained after time t4. However, due to the back electromotive force generated in solenoid coil 13b, the value of the voltage of solenoid coil 13b, i.e., the value of the voltage at node P1, increases from V2 to reach threshold value VT2 at time t5 and reaches maximum value V3 at time t6. At time t7, the back electromotive force generated in the solenoid coil 13b begins to decrease, and the voltage value of the solenoid coil 13b, i.e., the voltage value at the connection point P1, begins to decrease from the maximum value V3. At time t8, a part of the valve element 13a that had been in contact with the stopper separates from the stopper, and the valve element 13a and plunger begin to move toward their initial positions due to the biasing force of the spring. At time t9, the voltage value of the solenoid coil 13b, i.e., the voltage value at the connection point P1, decreases and reaches the threshold value VT2. At time t10, the back electromotive force generated in the solenoid coil 13b disappears, the valve element 13a and plunger return to their initial positions, the valve element 13a enters a fully closed state, and the voltage value of the solenoid coil 13b, i.e., the voltage value at the connection point P1, reaches a constant value V1.

[0074] In the process of step S15, the microcomputer 152 stops the second counting process and calculates the count value n2 counted by the second counting process as the valve closing response delay length Toff, which is the length of time of the valve closing response delay in response to a valve closing command when the valve element 13a of the fuel injection valve 13 closes. This completes the process of step S15, and the valve closing response delay length calculation process proceeds to the process of step S16.

[0075] Here, as shown in FIG. 6, at time t9, the second counting process is stopped and the count value reaches n2.

[0076] In the process of step S16, the microcomputer 152 calculates the difference between the valve-closing response delay length Toff calculated in the process of step S15 and a predetermined reference value as a second difference. This completes the process of step S16, and the valve-closing response delay length calculation process proceeds to the process of step S17.

[0077] In the process of step S17, microcomputer 152 uses the second difference value calculated in the process of step S16 and each of the second difference values ​​calculated from the first closing valve response delay length calculation process after the current start of engine 1 to the previous closing valve response delay length calculation process to calculate a second average value which is the average value of each of the second difference values ​​calculated from the first closing valve response delay length calculation process after the current start of engine 1 to the current closing valve response delay length calculation process. This completes the process of step S17, and the closing valve response delay length calculation process proceeds to the process of step S18.

[0078] In the process of step S18, the microcomputer 152 corrects the second average value calculated in the process of step S17 using the voltage of battery B to calculate the corrected second average value FToff, which then ends the valve closing response delay length calculation process.

[0079] <Command output timing correction processing> The command output timing correction process executed by the internal combustion engine control device 150 according to the embodiment of the present invention will be described in detail with reference to FIG.

[0080] The command output timing correction process shown in Fig. 5 starts at the timing when the opening valve response delay length calculation process shown in Fig. 3 and the closing valve response delay length calculation process shown in Fig. 4 are completed, and the command output timing correction process proceeds to the process of step S21. The command output timing correction process shown in Fig. 5 is executed every time the opening valve response delay length calculation process shown in Fig. 3 and the closing valve response delay length calculation process shown in Fig. 4 are completed.

[0081] In the process of step S21, the microcomputer 152 reads the corrected first average value FTo which was calculated in the process of step S8 of the valve-opening response delay length calculation process and stored in the memory. This completes the process of step S21, and the command output timing correction process proceeds to the process of step S22.

[0082] In the process of step S22, the microcomputer 152 reads the corrected second average value FToff calculated in the process of step S18 of the valve-closing response delay length calculation process and stored in the memory, thereby completing the process of step S22, and the command output timing correction process proceeds to the process of step S23.

[0083] In the process of step S23, the microcomputer 152 calculates a difference value ΔQt by subtracting the corrected first average value FTon read in the process of step S21 from the corrected second average value FToff read in the process of step S22. This completes the process of step S23, and the command output timing correction process proceeds to the process of step S24.

[0084] In the process of step S24, the microcomputer 152 corrects at least one of the output timing of the valve-open command and the output timing of the valve-open command based on the difference value ΔQt calculated in the process of step S23, thereby completing the command output timing correction process.

[0085] In the internal combustion engine control device 150 according to this embodiment, a microcomputer 152 having an input port 153 to which an electrical signal indicating that the applied voltage to the solenoid coil 13b has reached the timing to execute interrupt processing is input, outputs a valve-opening command to a drive circuit 157 to open the fuel injection valve 13, and derives a valve-opening response delay length in response to the valve-opening command when the fuel injection valve 13 opens, based on the electrical signal input to the input port 153 while the valve-opening command is being output. The valve-opening response delay length is the length of time from when the microcomputer 152 outputs the valve-opening command until the applied voltage increases and reaches the threshold value VT1. The applied voltage is detected based on the current passed through the solenoid coil 13b, thereby improving the injection accuracy of the fuel injection valve.

[0086] The present invention is not limited to the above-described embodiments in terms of the type, shape, arrangement, number, etc. of the components, and it goes without saying that the components can be appropriately modified within the scope of the gist of the invention, such as by appropriately replacing them with components that have equivalent effects.

[0087] Specifically, in the above embodiment, the flowchart shown in FIG. 5 may be started and closed in response to the execution of at least one of the valve-opening response delay length calculation process shown in FIG. 3 and the valve-closing response delay length calculation process shown in FIG. 4. In this case, for values ​​calculated in the executed process, the calculated value is read, and for values ​​to be calculated in processes that have not been executed, a predetermined value such as zero is read. [Industrial Applicability]

[0088] As described above, the present invention provides an internal combustion engine control device that can improve the injection accuracy of a fuel injection valve, and because of its versatile and universal nature, it is expected to be widely applicable to internal combustion engine control devices for saddle-ride vehicles and the like. [Explanation of symbols]

[0089] 1...Engine (internal combustion engine) 2...Cylinder block 2a...cylinder 3…Cooling water passage 4...Piston 5...Connecting rod 6...Crankshaft 7...Relacta 7a…teeth part 8...Cylinder head 9...Combustion chamber 10...Spark plug 11...Intake pipe 11a...intake passage 12...Intake valve 13...Fuel injection valve 13a...Valve body 13b...Solenoid coil 14...Throttle device 14a...Throttle valve 15...Exhaust pipe 15a...Exhaust passage 16...Exhaust valve 17...Catalyst 101...Water temperature sensor 102...Crank angle sensor 103...Intake pressure sensor 104...Throttle opening sensor 105...O2 sensor 106...Accelerator opening sensor 107...Voltage sensor 150...Internal combustion engine control device 152...microcomputer 153 (153a, 153b)...input port 154...Output port 155...Waveform shaping circuit 156...A / D conversion circuit 157...Drive circuit 158...Input circuit 160...Connector 161, 162, 163, 164... operational amplifiers P1~P29...Connection points R1 to R21: Resistor elements C1 to C7: Capacitors F1, F2...Filter circuit G1: Voltage detection circuit T1...Switch circuit

Claims

1. an electric circuit that switches between a powered state and a non-powered state of an actuator that opens and closes a fuel injection valve of an internal combustion engine; a microcontroller having an external interrupt port; and The external interrupt port includes: an electrical signal indicating that it is time to execute an interrupt process for the voltage applied to the actuator is input; The microcomputer outputting a valve opening command to the electric circuit to open the fuel injector, and deriving a valve opening response delay length in response to the valve opening command when the fuel injector opens based on the electric signal input to the external interrupt port during the output of the valve opening command; The valve opening response delay length is the length of time from when the microcomputer outputs the valve open command until when the applied voltage increases and reaches a predetermined threshold value, The applied voltage is The detection is based on a current flowing through the actuator. An internal combustion engine control device characterized by:

2. The applied voltage is The current flowing through the actuator is detected by flowing through a shunt resistor.

2. The internal combustion engine control device according to claim 1.

3. The valve opening response delay length is the length of time from when the microcomputer outputs the valve open command until the applied voltage amplified by the amplifier increases and reaches the threshold value, 3. The internal combustion engine control device according to claim 2.

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