Internal combustion engine control device

Abstract

An internal combustion engine control device 50 comprises: an electric circuit (157) that switches between an energized state and a non-energized state of an actuator (13b) that drives a valve body (13a) of a fuel injection valve (13); and a microcomputer (152) that outputs to the electric circuit (157) an open-valve command to open the valve body (13a) and thus open the fuel injection valve (13), that outputs to the drive circuit (157) a close-valve command to close the valve body (13a) and thus close the fuel injection valve (13), and that adjusts the interval between the timing for the output of the open-valve command and the timing for the output of the close-valve command, on the basis of an open-valve response delay length with respect to the open-valve command when the fuel injection valve (13) is opened, and a close-valve response delay length with respect to the close-valve command when the fuel injection valve (13) is closed. The microcomputer (152) lengthens the interval as the open-valve response delay length increases, and shortens the interval as the close-valve response delay length increases.

Description

Internal combustion engine control device

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

[0002] In recent years, fuel injection valves have been adopted for internal combustion engines to improve their 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] Under such circumstances, Patent Document 1 discloses a control device for an internal combustion engine that detects the voltage between the terminals of a solenoid coil for each fuel injection device of each cylinder, and when the valve disc closes from an open state, detects a change in induced electromotive force due to a change in the acceleration of the armature when the armature separates from the valve disc after contacting the valve seat as the voltage between the terminals of the solenoid coil, and determines the timing at which the second-order differential value becomes maximum as the timing at which the valve disc has completed closing.

[0004] International Publication No. 2013 / 191267

[0005] However, according to the inventor's investigation, in the configuration of Patent Document 1, when the valve disc closes from an open state, the valve closing delay time is estimated by using the timing at which the second-order differential value of the voltage between the terminals of the solenoid coil becomes maximum, which is determined by the change in induced electromotive force caused by the change in acceleration of the armature when the armature separates from the valve disc after coming into contact with the valve seat. However, there is no disclosure whatsoever about adjusting the fuel injection amount using the valve opening delay time, etc.

[0006] The present invention was made based on the above considerations, and aims to provide an internal combustion engine control device that can appropriately adjust the fuel injection amount using the valve opening response delay length and valve closing delay length of the fuel injection valve.

[0007] In order to achieve the above object, in one aspect, the present invention provides an internal combustion engine control device comprising: an electric circuit that switches between an energized state and a de-energized state of an actuator that drives a valve element of a fuel injection valve of an internal combustion engine; and a microcomputer that outputs a valve open command to the electric circuit to open the valve element and open the fuel injection valve, and outputs a valve close command to the electric circuit to close the valve element and close the fuel injection valve, and adjusts the interval between the timing of outputting the valve open command and the timing of outputting the valve close command based on a valve opening response delay length in response to the valve open command when the fuel injection valve opens, and a valve closing response delay length in response to the valve close command when the fuel injection valve closes, wherein the microcomputer increases the interval as the valve opening response delay length increases, and decreases the interval as the valve closing response delay length increases.

[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 drives a valve element of a fuel injection valve of an internal combustion engine, and a microcomputer that outputs a valve open command to the electric circuit to open the valve element and open the fuel injection valve, and outputs a valve close command to the electric circuit to close the valve element and close the fuel injection valve, and adjusts the interval between the timing of outputting the valve open command and the timing of outputting the valve close command based on the valve opening response delay length in response to the valve open command when the fuel injection valve opens, and the valve closing response delay length in response to the valve close command when the fuel injection valve closes, so that the longer the valve opening response delay length, the longer the microcomputer makes this interval, and the longer the valve closing response delay length, the shorter the interval.Therefore, the fuel injection amount can be appropriately adjusted using the valve opening response delay length and valve closing delay length of the fuel injection valve.

[0009] FIG. 1 is a schematic diagram showing the configuration of an internal combustion engine control device (hereinafter sometimes referred to as engine control device) according to an embodiment of the present invention, together with an internal combustion engine (hereinafter sometimes referred to as engine). FIG. 2 is a schematic diagram mainly showing the configuration of an input circuit of the engine control device according to this embodiment. FIG. 3 is a flowchart showing an example of a process for calculating a valve opening response delay length of the engine control device according to this embodiment. FIG. 4 is a flowchart showing an example of a process for calculating a valve closing response delay length of the engine control device according to this embodiment. FIG. 5 is a flowchart showing an example of a process for correcting a command output timing of the engine control device according to this embodiment. FIG. 6 is a time chart showing an example of the operation of the engine control device according to this embodiment.

[0010] Hereinafter, engine control devices according to embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[0011] <Configuration of Engine> First, with reference to FIG. 1, the configuration of an engine to which the engine control device of this embodiment is applied will be described in detail.

[0012] FIG. 1 is a schematic diagram showing the configuration of an engine control device according to this embodiment together with an engine.

[0013] As shown in FIG. 1 , the engine 1 is typically a four-stroke reciprocating internal combustion engine mounted on a vehicle such as a motorcycle (not shown) and equipped with a battery B. The engine 1 is controlled by an engine control device 50 and includes a cylinder block 2. 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 typically 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. The water temperature sensor 101 outputs an electrical signal indicating the coolant temperature to the engine control device 50. If the engine 1 were air-cooled, a temperature sensor (not shown) capable of detecting the temperature of the engine 1 would be provided in the cylinder block 2 or elsewhere instead of the water temperature sensor 101.

[0014] 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, rotating coaxially with the crankshaft 6. A plurality of teeth 7a are provided on the outer circumferential surface of the reluctor 7, and are arranged in a predetermined pattern along 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 engine control device 50 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 engine control device 50.

[0015] A cylinder head 8 is attached to the top of the cylinder block 2. 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 cooperate to define an internal space which serves as a combustion chamber 9.

[0016] 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 the combustion chamber 9. The ignition operation of the spark plug 10 is controlled by the engine control device 50, which controls the supply of electricity to an ignition coil (not shown).

[0017] 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 engine control device 50. 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 engine control device 50. The fuel injection valve 13 mainly has a valve element 13a, a solenoid coil 13b which is an actuator for the valve element 13a, and a plunger (not shown) which receives magnetic force from the solenoid coil 13b and moves the valve element 13a, and the opening and closing operations of the valve element 13a via the plunger are controlled by the engine control device 50 by controlling the supply of electricity to the solenoid coil 13b.

[0018] 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 within the cylinder head 8 and 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, typically a three-way catalyst, is provided in the exhaust pipe 15 downstream of the exhaust valve 16 to purify the exhaust gas discharged from the combustion chamber 9, and an O2 sensor 105 is provided upstream of and close to the catalyst 17 to detect the oxygen concentration in the exhaust gas. 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 the engine control device 50.

[0019] An accelerator opening sensor 106 is attached to a steering wheel or the like (not shown) of the vehicle, and an 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. The accelerator opening sensor 106 outputs an electric signal indicating a voltage corresponding to the accelerator opening to the engine control device 50. A voltage sensor 107 detects the voltage of battery B mounted on the vehicle. The voltage sensor 107 outputs an electric signal indicating the voltage of battery B to the engine control device 50.

[0020] <Configuration of Engine Control Device> Next, with further reference to FIG. 2, the configuration of the engine control device 50 in this embodiment will be described in detail.

[0021] 2 is a schematic diagram mainly showing the configuration of an input circuit of an engine control device according to this embodiment. In the figure, connection points A and the like provided on the solid electrical wiring connecting electrical components are nodes that connect the electrical components. Details such as the symbols of the electrical wiring and the terminals of the electrical components are omitted from the illustration. An electrical connection may be simply referred to as a connection, and the potential difference between the potential of a certain location and the ground potential may be referred to as the voltage at that location.

[0022] First, as shown in FIG. 1, the engine control device 50 is configured by an ECU (Electronic Control Unit) 150, which is an electronic control device mounted on a vehicle and controls the operation of the engine 1.

[0023] The ECU 150 is an arithmetic processing device that includes a CPU (Central Processing Unit) 152a and 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 ECU 150 also includes a waveform shaping circuit 155 that is an electric circuit that shapes the waveform of an electric signal from the crank angle sensor 102, an A / D conversion circuit 156 that 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 that is an electric circuit that has switching elements such as transistors and switches the energized state and de-energized state of the solenoid coil 13b of the fuel injection valve 13, and an input circuit 158 ​​that is an electric circuit to which an electric signal indicating the voltage applied to the solenoid coil 13b is input. The microcomputer 152 also includes a memory and a timer (not shown), and the memory stores necessary control and processing programs and control and processing data.

[0024] 2, the drive circuit 157 is provided between the fuel injection valve 13 and the microcomputer 152, and is connected to the fuel injection valve 13 via a connection point A downstream of the fuel injection valve 13, and 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 output from the microcomputer 152 via the output port 154 to the drive circuit 157, the switching element of the drive circuit 157 changes from an OFF state to an ON state, thereby placing the fuel injection valve 13 in a conductive state in which current flows from the battery B shown in FIG. On the other hand, when the microcomputer 152 outputs an OFF signal (valve close command), which is a relatively low-level electrical signal with a low voltage, to the drive circuit 157 via the output port 154, the drive circuit 157 changes its switching element from an ON state to an OFF state, thereby bringing the fuel injection valve 13 into a non-energized state in which no current flows from the battery B to the solenoid coil 13b of the fuel injection valve 13. In the figure, an electrical signal indicating a voltage corresponding to the valve open command and the valve close command is shown as a command signal CINJ. Furthermore, the connection point A is typically set at the low-potential end of the solenoid coil 13b, and an IGP power supply, which is connected to the battery B when an ignition switch (not shown) changes from an OFF state to an ON state, is connected to the high-potential end of the solenoid coil 13b.

[0025] As shown in FIG. 2, an input circuit 158 ​​provided separately from the waveform shaping circuit 155 and the A / D conversion circuit 156 mainly includes comparators 161 , 162 and 163 .

[0026] The comparator 161 is provided after the fuel injector 13 and the IGP power supply, and the non-inverting input terminal of the comparator 161 is connected to the fuel injector 13 via a noise filter circuit F1.

[0027] The noise filter circuit F1 includes resistors R1, R2, and R3 and a capacitor C1. The resistors R1, R2, and R3 are provided in this order downstream of the fuel injector 13. One terminal of the resistor R1 is connected to node A, and the other terminal of the resistor R1 is connected to node B. One terminal of the resistor R2 is connected to node B, and the other terminal of the resistor R2 is connected to node C. One terminal of the capacitor C1 is connected to node B, and the other terminal of the capacitor C1 is grounded. Furthermore, one terminal of the resistor R3 is connected to node C, and the other terminal of the resistor R3 is grounded.

[0028] The inverting input terminal of the comparator 161 is connected to the IGP power supply via a 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, and R6 and a capacitor C2. The resistors R4, R5, and R6 are provided in this order downstream of the IGP power supply. The resistors R1 and R4 are typically set to have the same resistance, and the resistors R2 and R5 are typically set to have the same resistance. The capacitors C1 and C2 are typically set to have the same capacitance. One terminal of the resistor R4 is connected to the IGP power supply, and the other terminal of the resistor R4 is connected to node D. One terminal of the resistor R5 is connected to node D, and the other terminal of the resistor R5 is connected to node E. One terminal of the capacitor C2 is connected to node D, and the other terminal of the capacitor C2 is grounded. One terminal of the resistor R6 is connected to the connection point E, and the other terminal of the resistor R6 is grounded via the connection point F.

[0030] The inverting input terminal of the comparator 161 is connected to a connection point E. The power supply voltage of the comparator 161 is supplied by a power supply voltage VCC, which is connected to the power supply terminal of the comparator 161 via a connection point G and is grounded via a connection point F. In addition, the output terminal of the comparator 161 is connected to the non-inverting input terminals of the comparators 162 and 163 via a connection point H.

[0031] Here, if the voltage value indicated by the electrical signal input to the non-inverting input terminal of the comparator 161, which is obtained by dividing the voltage at connection point A at the low potential end of the solenoid coil 13b by the resistance voltage division between the combined resistance of resistor elements R1 and R2 and the resistance of resistor 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 voltage division between the combined resistance of resistor elements R5 and R6 and the resistance of resistor element R6, then a high level electrical signal indicating a relatively high voltage is output from the output terminal of the comparator 161. On the other hand, when the voltage value indicated by the electrical signal input to the non-inverting input terminal of the comparator 161, which is obtained by dividing the voltage at the connection point A 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 value 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 comparator 161. In other words, the electrical signal output in this manner indicates a high-level voltage if the input voltage from the connection point A side, i.e., the solenoid coil 13b side, is equal to or greater than the threshold voltage, where the reference voltage is 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. On the other hand, when the input voltage from the connection point A side, i.e., the solenoid coil 13b side, is less than the threshold voltage, the electrical signal indicates a low-level voltage. Therefore, the magnitude of the output voltage output from the output terminal of the comparator 161 is equal to or greater than a predetermined value corresponding to the threshold voltage. Note that the comparator 161 and the noise filter circuits F1 and F2 may be omitted, if necessary.

[0032] The power supply voltage VCC not only supplies the power supply voltage to the comparator 161 but also supplies the power supply voltage to each of the comparators 162 and 163, and utilizes the voltage of the battery B.

[0033] The non-inverting input terminal of comparator 162 is connected to the output terminal of comparator 161 via connection point H, and the inverting input terminal of comparator 162 is connected to the power supply voltage VCC via connection points G, I, and J in this order. The non-inverting input terminal of comparator 163 is connected to the output terminal of comparator 161 via connection point H, and the inverting input terminal of comparator 163 is connected to the power supply voltage VCC via connection points G, I, J, and K in this order. One terminal of resistor R7 is connected to connection point I, and the other terminal of resistor R7 is connected to connection point J. One terminal of resistor R8 is connected to connection point J, and the other terminal of resistor R8 is connected to connection point K. One terminal of resistor R9 is connected to connection point K, and the other terminal of resistor R9 is grounded. The power supply voltage of the comparator 162 is supplied by the power supply voltage VCC, which is connected to the power supply terminal of the comparator 162 via connection points G, I, and L and is grounded via connection point M. The output terminal of the comparator 162 is connected to port 153b of the input port 153 of the microcomputer 152 via connection point O. The power supply voltage of the comparator 163 is supplied by the power supply voltage VCC, which is connected to the power supply terminal of the comparator 163 via connection points G, I, L, N, and P and is grounded via connection point Q. In addition, the output terminal of the comparator 163 is connected to port 153a of the input port 153 of the microcomputer 152 via connection point R.

[0034] Here, when the voltage value indicated by the electrical signal output from the output terminal of the comparator 161 and input to the non-inverting input terminal of the comparator 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 R7 and the combined resistance of the resistor elements R8 and R9, a high-level electrical signal JOff indicating a relatively high voltage is output from the output terminal of the comparator 162. On the other hand, when the voltage value indicated by the electrical signal output from the output terminal of the comparator 161 and input to the non-inverting input terminal of the comparator 162 is less than the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance of the resistor element R7 and the combined resistance of the resistor elements R8 and R9, a low-level electrical signal JOff indicating a relatively low voltage is output. In other words, with the reference voltage, which is such a divided voltage, as the off threshold voltage, the electrical signal JOff indicates a high-level voltage when the input voltage from the comparator 161 side, i.e., the solenoid coil 13b side, is equal to or higher than the off threshold voltage, and indicates a low-level voltage when the input voltage from the comparator 161 side, i.e., the solenoid coil 13b side, is lower than the off threshold voltage, and therefore the electrical signal JOff serves as a determination signal indicating whether or not the input voltage from the comparator 161, i.e., the solenoid coil 13b side, has reached a predetermined off threshold voltage. The electrical signal JOff, which is such a determination signal, is input to the input port 153b.

[0035] Furthermore, when the voltage value indicated by the electrical signal output from the output terminal of the comparator 161 and input to the non-inverting input terminal of the comparator 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 R7 and R8 and the resistance of the resistor element R9, a high-level electrical signal JOn indicating a relatively high voltage is output from the output terminal of the comparator 163. On the other hand, when the voltage value indicated by the electrical signal output from the output terminal of the comparator 161 and input to the non-inverting input terminal of the comparator 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 R7 and R8 and the resistance of the resistor element R9, a low-level electrical signal JOn indicating a relatively low voltage is output. In other words, with the reference voltage, which is such a divided voltage, as the on-threshold voltage, the electrical signal JOn indicates a high-level voltage when the input voltage from the comparator 161 side, i.e., the solenoid coil 13b side, is equal to or higher than the on-threshold voltage, and indicates a low-level voltage when the input voltage from the comparator 161 side, i.e., the solenoid coil 13b side, is lower than the on-threshold voltage, and therefore the electrical signal JOn serves as a determination signal indicating whether the input voltage from the comparator 161, i.e., the solenoid coil 13b side, has reached a predetermined on-threshold voltage. The electrical signal JOn, which is such a determination signal, is input to the input port 153a.

[0036] One terminal of the resistor R10 is connected to the connection point N, and the other terminal of the resistor R10 is connected to the connection point O. One terminal of the capacitor C3 is connected to the connection point O, and the other terminal of the capacitor C3 is grounded via the connection point M. The resistor R10 and capacitor C3, which are connected to the VCC power supply, are intended to maintain the voltage value of the electrical signal JOff output from the output terminal of the comparator 162 so that it does not fall below a predetermined value.

[0037] Furthermore, one terminal of the resistor R11 is connected to the connection point P, and the other terminal of the resistor R11 is connected to the connection point R. The resistances of the resistors R10 and R11 are typically set to be equal to each other. One terminal of the capacitor C4 is connected to the connection point R, and the other terminal of the capacitor C4 is grounded via the connection point Q. The resistor R11 and capacitor C4, connected to the VCC power supply, are intended to prevent the voltage of the electrical signal JOn output from the output terminal of the comparator 163 from falling below a predetermined value, similar to the voltage of the electrical signal JOff output from the output terminal of the comparator 162. The resistances of the resistors R10 and R11 are typically set to be equal to each other, and the capacitances of the capacitors C3 and C4 are typically set to be equal to each other.

[0038] In addition, the ECU 150 controls the operation of various control objects such as the spark plug 10 and the fuel injection valve 13 based on output signals from various sensors acquired via the waveform shaping circuit 155, the A / D conversion circuit 156, the input circuit 158, etc., and also reads out the necessary control / processing programs and control / processing data from memory and executes the control / processing programs, thereby controlling the operating state of the engine 1.

[0039] Furthermore, the ECU 150 includes a drive circuit 157, which is an electric circuit that switches between an energized state and a de-energized state of the solenoid coil 13b, which is an actuator that drives the valve element 13a of the fuel injection valve 13, and a microcomputer 152 that outputs a valve open command to the drive circuit 157 to open the valve element 13a to open the fuel injection valve 13, and outputs a valve close command to the drive circuit 157 to close the valve element 13a to close the fuel injection valve 13, and adjusts the interval between the timing of outputting the valve open command and the timing of outputting the valve close command based on the length of the valve open response delay to the valve open command when the fuel injection valve 13 opens and the length of the valve close response delay to the valve close command when the fuel injection valve 13 closes, so that the longer the valve open response delay, the longer the microcomputer 152 makes this interval, and the longer the valve close response delay, the shorter the interval.

[0040] The engine control device 50 having the configuration described above executes, as an interrupt process, a command output timing correction process for correcting the output timing of a valve-open command or a valve-close command to be output to the drive circuit 157 that drives the fuel injection valve 13. Hereinafter, with further reference to Figures 3 to 6, the operation of the engine control device 50 when executing the command output timing correction process and the preceding process as an interrupt process will be described in detail.

[0041] <Operation of Engine Control Device> Figure 3 is a flowchart showing an example of a process for calculating a valve-opening response delay length of the engine control device in this embodiment, Figure 4 is a flowchart showing an example of a process for calculating a valve-closing response delay length of the engine control device in this embodiment, Figure 5 is a flowchart showing an example of a process for correcting a command output timing of the engine control device in this embodiment, and Figure 6 is a time chart showing an example of an operation of the engine control device in this embodiment.

[0042] First, the process for calculating the valve opening response delay length will be described with reference mainly to FIGS.

[0043] 3 starts when an ignition switch (not shown) is turned on from an off state and the ECU 150 is started, and the process of calculating the valve opening response delay length proceeds to step S1. While the ECU 150 is in the started state, the process of calculating the valve opening response delay length is repeatedly executed at predetermined control intervals by reading the necessary control / processing programs and control / processing data from memory. The valve opening response delay length refers to the length of time from the start of output of the valve open command to the time when the valve disc 13a has completed opening or can be considered to have completed opening.

[0044] 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 process of calculating the valve-opening response delay length proceeds to the process of step S2.

[0045] In the process of step S2, the microcomputer 152 determines whether 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 proceeds to the process of step S3 to calculate the valve-open response delay length. 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. Note that the data of the predetermined value is referenced from data stored in memory.

[0046] 6, at time t1, the microcomputer 152 outputs an ON signal (valve-open command) that is a high-level electrical signal CINJ from the output port 154 to the drive circuit 157, and the voltage H of the valve-open command is greater than a predetermined value A. Also at time t1, the solenoid coil 13b is energized, and current begins to flow from the battery B side to the solenoid coil 13b. At this time, a back electromotive force is generated in the solenoid coil 13b, causing the current flowing from the battery B side through the solenoid coil 13b to gradually increase. At the same time, a magnetic force begins to be applied to the plunger (not shown) of the fuel injection valve 13. The plunger, together with the valve body 13a attached thereto, begins to move against the biasing force of a spring (not shown), fuel pressure, frictional force, and the like (not shown). The voltage applied to the solenoid coil 13b, i.e., the voltage at the connection point A, gradually decreases from V1, which is derived from the voltage of the battery B. 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 starts at time t1.

[0047] 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 process of calculating the valve-open response delay length proceeds to the process of step S4. Note that the series of processes starting from the process of step S3 constitutes interrupt processing.

[0048] As shown in FIG. 6, at time t1, the microcomputer 152 starts a first counting process to count the elapsed time since the valve open command was output from the output port 154 to the drive circuit 157.

[0049] In step S4, the microcomputer 152 determines whether the value of the input voltage to the input port 153a, which is the first external interrupt port, i.e., the voltage value of the electrical signal JOn output from the output terminal of the comparator 163 and input to the input port 153a, has changed from VH1 or more to VL1 or less (<VH1). If the result of the determination is that the value of this voltage has changed from VH1 or more to VL1 or less, the microcomputer 152 proceeds to step S5 to calculate the valve-opening response delay length. On the other hand, if the result of the determination is that the value of this voltage has not changed from VH1 or more to VL1 or less, the microcomputer 152 repeats step S4. Note that determining that the value of this voltage has changed from VH1 or more to VL1 or less is equivalent to determining that a falling edge of this voltage has occurred.

[0050] 6, at time t2, the value of the input voltage to input port 153a, which is the first external interrupt port, changes from VH1 to VL1. Also, at time t2, the value of the voltage applied to solenoid coil 13b of fuel injector 13, i.e., the value of the voltage at node A, drops to and becomes equal to first threshold value VT1, which is the reference voltage obtained by dividing the voltage of the VCC power supply by the resistance division between the combined resistance of resistor elements R7 and R8 and the resistance of resistor element R9. The valve open command, i.e., the voltage H, is maintained until time t4, but at time T3 between time t2 and time t4, the back electromotive force generated in the solenoid coil 13b disappears, and a part of the valve body 13a abuts against a stopper (not shown), causing the valve body 13a and the plunger to stop, maintaining the valve body 13a in a fully open state, and the value of the voltage applied to the solenoid coil 13b reaches a constant value V2, which is maintained thereafter until time t4.

[0051] In the process of step S5, the microcomputer 152 stops the first counting process and calculates the first count value CN1 counted by the first counting process as a valve-opening response delay length Ton, which is the length of time of the valve-opening response delay in response to a valve-opening command when the valve body 13a of the fuel injection valve 13 opens. This completes the process of step S5, and the process of calculating the valve-opening response delay length proceeds to the process of step S6.

[0052] As shown in FIG. 6, at time t2, the first counting process is stopped and the count value reaches CN1.

[0053] In step S6, the microcomputer 152 calculates the difference between the valve-opening response delay length Ton calculated in step S5 and a predetermined reference value, which is typically the mass-production median value, as a first difference. This completes step S6, and the process of calculating the valve-opening response delay length proceeds to step S7.

[0054] In the process of step S7, the microcomputer 152 uses the first difference value calculated in the process of step S6 and each of the first difference values ​​calculated from the process of calculating the first valve-opening response delay length after the current start of the engine 1 to the process of calculating the previous valve-opening response delay length to calculate a first average value, which is the average value of each of the first difference values ​​calculated from the process of calculating the first valve-opening response delay length after the current start of the engine 1 to the process of calculating the current valve-opening response delay length. This completes the process of step S7, and the process of calculating the valve-opening response delay length proceeds to the process of step S8.

[0055] In the process of step S8, the microcomputer 152 corrects the first average value calculated in the process of step S7 using the voltage of battery B to calculate the corrected first average value F Ton, thereby completing the current series of processes for calculating the valve-opening response delay length.

[0056] Next, the process for calculating the valve closing response delay length will be described with reference to Figures 4 and 6. Note that the process for calculating the valve opening response delay length and the process for calculating the valve closing response delay length may be performed in combination with one or both of them as necessary.

[0057] 4 starts when an ignition switch (not shown) is turned on from an off state and the ECU 150 is started, and the process of calculating the valve closing response delay length proceeds to step S11. While the ECU 150 is in the started state, the process of calculating the valve closing response delay length is repeatedly executed at predetermined control intervals by reading out the necessary control / processing programs and control / processing data from memory. The valve closing response delay length refers to the length of time from the start of output of the valve close command to the time when the valve disc 13a is closed or can be considered to be closed.

[0058] 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.

[0059] 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 proceeds to the process of step S13 to calculate the valve close response delay length. 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 a predetermined value, the microcomputer 152 determines that a valve close command has not been output, and repeats the process of step S12. Note that the data of the predetermined value is referenced from data stored in memory.

[0060] 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. Also at time t4, the solenoid coil 13b is de-energized, and no current flows from battery B 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 node A, 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, and the output of the valve close command begins at time t4.

[0061] In the process of step S13, the microcomputer 152 starts a second counting process that counts 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 process of calculating the valve close response delay length proceeds to the process of step S14. Note that the series of processes starting from the process of step S13 constitutes an interrupt process.

[0062] As shown in FIG. 6, at time t4, the microcomputer 152 starts a second counting process for counting the time that has elapsed since the valve close command was output from the output port 154 to the drive circuit 157.

[0063] In step S14, the microcomputer 152 determines whether the value of the input voltage to the input port 153b, which is the second external interrupt port, i.e., the voltage value of the electrical signal JOff output from the output terminal of the comparator 162 and input to the input port 153b, has changed from VH2 or more to VL2 or less (<VH2). If the result of the determination is that the value of this voltage has changed from VH2 or more to VL2 or less, the microcomputer 152 proceeds to step S15 to calculate the valve closing response delay length. On the other hand, if the result of the determination is that the value of this voltage has not changed from VH2 or more to VL2 or less, the microcomputer 152 repeats step S14. Note that determining that the value of this voltage has changed from VH2 or more to VL2 or less is equivalent to determining that a falling edge of this voltage has occurred.

[0064] 6, at time t9, the input voltage to input port 153b, which is the second external interrupt port, changes from VH2 to VL2. At time t9, the voltage applied to solenoid coil 13b of fuel injector 13, i.e., the voltage at node A, decreases to and becomes equal to second threshold voltage VT2, which is a reference voltage obtained by dividing the VCC power supply voltage through the resistance of resistor R7 and the combined resistance of resistors R8 and R9. The valve close command, i.e., voltage L, is maintained from time t4 onward. However, due to the back electromotive force generated in solenoid coil 13b, the voltage of solenoid coil 13b, i.e., the voltage at node A, increases from V2 to the second threshold voltage VT2 at time t5 and reaches a 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 of the solenoid coil 13b, i.e., the voltage at connection point A, begins to decrease from the maximum value V3. At time t8, a portion 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 of the solenoid coil 13b, i.e., the voltage at connection point A, decreases and reaches the second threshold voltage 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 becomes fully closed, and the voltage of the solenoid coil 13b, i.e., the voltage at connection point A, reaches a constant value V1. From the viewpoint of accurately calculating the valve closing response delay length, it is preferable that the second threshold voltage VT2 be set to a value smaller than the voltage VS at time t8 when a part of the valve body 13a that was in contact with the stopper separates from the stopper.

[0065] In the process of step S15, the microcomputer 152 stops the second counting process and calculates the second count value CN2 counted by the second counting process as a 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 body 13a of the fuel injection valve 13 closes. This completes the process of step S15, and the process of calculating the valve closing response delay length proceeds to the process of step S16.

[0066] As shown in FIG. 6, at time t9, the second counting process is stopped and the count value reaches CN2.

[0067] In the process of step S16, the microcomputer 152 calculates, as a second difference, the difference between the valve-closing response delay length Toff calculated in the process of step S15 and a predetermined reference value, which is typically the mass-production median value. This completes the process of step S16, and the process of calculating the valve-closing response delay length proceeds to the process of step S17.

[0068] In the process of step S17, the microcomputer 152 uses the second difference value calculated in the process of step S16 and each of the second difference values ​​calculated from the process of calculating the first closing valve response delay length after the current start of the engine 1 to the process of calculating the previous closing valve response delay length to calculate a second average value which is the average value of each of the second difference values ​​calculated from the process of calculating the first closing valve response delay length after the current start of the engine 1 to the process of calculating the current closing valve response delay length. This completes the process of step S17, and the process of calculating the valve closing response delay length proceeds to the process of step S18.

[0069] 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, thereby completing the current series of processes for calculating the valve closing response delay length.

[0070] Next, the correction process for the command output timing will be described mainly with reference to FIG.

[0071] The flowchart shown in Figure 5 is started subsequently in response to the execution of at least one of the process for calculating the valve-opening response delay length shown in Figure 3 and the process for calculating the valve-closing response delay length shown in Figure 4, and the process for correcting the command output timing proceeds to the process of step S21. This process for correcting the command output timing is executed by reading the necessary control / processing program and control / processing data from memory. Note that the flowchart shown in Figure 5 may also be started in response to the execution of at least one of the process for calculating the valve-opening response delay length shown in Figure 3 and the process for calculating the valve-closing response delay length shown in Figure 4, and in such a case, the value calculated in the executed process may be read, and a predetermined value such as zero may be read for the value to be calculated in the process not yet executed.

[0072] In step S21, the microcomputer 152 reads the corrected first average value FTon that was calculated in step S8 of the valve-opening response delay calculation process and stored in memory. This completes step S21, and the command output timing correction process proceeds to step S22.

[0073] In step S22, the microcomputer 152 reads the corrected second average value FToff that was calculated in step S18 of the calculation process for the valve closing response delay length and stored in memory. This completes step S22, and the process for correcting the command output timing proceeds to step S23.

[0074] 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 process of correcting the command output timing proceeds to the process of step S24.

[0075] In the process of step S24, the microcomputer 152 corrects the interval between the timing of outputting the valve open command and the timing of outputting the valve close command based on the corrected first average value FTon read in the process of step S21 and the corrected second average value FToff read in the process of step S22. This completes the process of step S24, and the process of correcting the command output timing proceeds to the process of step S25.

[0076] Specifically, in the processing of step S24, the longer the valve-opening response delay, the longer the interval between the timing of outputting the valve-opening command and the timing of outputting the valve-closing command, and the longer the valve-closing response delay, the shorter the interval between the timing of outputting the valve-opening command and the timing of outputting the valve-closing command, thereby optimizing the interval between the timing of outputting the valve-opening command and the timing of outputting the valve-closing command and appropriately adjusting the fuel injection amount.

[0077] In the process of step S25, the microcomputer 152 further corrects the interval corrected in the process of step S24 (the interval between the output timing of the valve open command and the output timing of the valve close command) based on the difference value ΔQt calculated in the process of step S23. This completes the process of correcting the current series of command output timings. Note that, if necessary, the process of step S25 may be omitted and the process of correcting the current series of command output timings may be completed with the process of step S24. Also, if necessary, the process of step S24 may be omitted and the interval between the output timing of the valve open command and the output timing of the valve close command may be corrected only by the process of step S25.

[0078] Specifically, taking note of the fact that the fuel injection valve 13 has a characteristic in which the length of the valve closing response delay is longer than the length of the valve opening response delay, in the processing of step S25, the microcomputer 152 shortens the interval corrected in the processing of step S24 the greater the difference between the length of the valve closing response delay and the length of the valve opening response delay, thereby making the interval between the timing of outputting the valve opening command and the timing of outputting the valve closing command more appropriate and more appropriately adjusting the fuel injection amount.

[0079] In the first aspect of the internal combustion engine control device 50 in this embodiment described above, the ECU 150 controls the drive circuit 157, which is an electric circuit that switches between an energized state and a de-energized state of the solenoid coil 13b, which is an actuator that drives the valve body 13a of the fuel injection valve 13, and outputs a valve open command to the drive circuit 157 to open the valve body 13a to open the fuel injection valve 13, and outputs a valve close command to the drive circuit 157 to close the valve body 13a to close the fuel injection valve 13, and controls the ECU 150 to output a valve open response to the valve open command when the fuel injection valve 13 opens. and a microcomputer 152 that adjusts the interval between the timing of outputting the valve open command and the timing of outputting the valve close command based on the delay length and the valve closing response delay length in response to the valve closing command when the fuel injection valve 13 closes. The longer the valve opening response delay length, the longer the microcomputer 152 makes this interval, and the longer the valve closing response delay length, the shorter the interval. This makes it possible to optimize the interval between the timing of outputting the valve open command and the timing of outputting the valve close command and to appropriately adjust the fuel injection amount.

[0080] In addition, in the second aspect of the internal combustion engine control device 50 of this embodiment, in addition to the first aspect, the closing response delay length of the fuel injection valve 13 is longer than the opening response delay length, and the microcomputer 152 shortens the interval between the timing of outputting the valve opening command and the timing of outputting the valve closing command the larger the difference between the closing response delay length and the opening response delay length, so that the interval between the timing of outputting the valve opening command and the timing of outputting the valve closing command can be made more appropriate, and the fuel injection amount can be more appropriately adjusted.

[0081] Furthermore, in a third aspect of the internal combustion engine control device 50 of this embodiment, in addition to the first or second aspect, the microcomputer 152 derives the valve opening response delay length and the valve closing response delay length based on an electrical signal that indicates the voltage applied to the solenoid coil 13b and is input to the microcomputer 152. Therefore, the voltage applied to the solenoid coil 13b can be acquired at a relatively short acquisition period and at an appropriate timing, and the required interrupt processing can be executed appropriately, thereby more appropriately adjusting the fuel injection amount.

[0082] Furthermore, in a fourth aspect of the internal combustion engine control device 50 of this embodiment, in addition to the third aspect, the valve opening response delay length is the length of time from the time the microcomputer 152 outputs a valve opening command to the time the voltage applied to the solenoid coil 13b decreases and reaches the first threshold value, and the valve closing response delay length is the length of time from the time the microcomputer 152 outputs a valve closing command to the time the voltage applied to the solenoid coil 13b decreases and reaches the second threshold value, so that the valve opening response delay length and the valve closing response delay length can be more appropriately derived.

[0083] In this embodiment, the solenoid coil 13b is used as an actuator. However, any actuator that exhibits voltage change characteristics similar to those of the solenoid coil 13b can be applied to the present invention.

[0084] Furthermore, 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 these components can be appropriately modified within the scope of the gist of the invention, such as by appropriately replacing the components with components that have equivalent effects.

[0085] As described above, the present invention provides an internal combustion engine control device that can appropriately adjust the fuel injection amount by using the valve opening response delay length and valve closing delay length of the fuel injection valve, and is expected to be widely applicable to internal combustion engine control devices for motorcycles due to its general-purpose, universal nature.

[0086] DESCRIPTION OF SYMBOLS 1...Engine (internal combustion engine) 2...Cylinder block 2a...Cylinder 3...Cooling water passage 4...Piston 5...Connecting rod 6...Crankshaft 7...Reluctor 7a...Tooth portion 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 50...Engine control device (internal combustion engine control device) 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...ECU 152...Microcomputer 152a...CPU 153 (153a, 153b)...input port 154...output port 155...waveform shaping circuit 156...A / D conversion circuit 157...drive circuit 158...input circuit 161, 162, 163...comparators A to L...connection points R1 to R12...resistance elements C1 to C4...capacitors F1, F2...filter circuits

Claims

1. An internal combustion engine control device comprising: an electric circuit that switches between an energized state and a de-energized state of an actuator that drives a valve element of a fuel injection valve of an internal combustion engine; and a microcomputer that outputs a valve open command to said electric circuit to open the valve element and open the fuel injection valve, and outputs a valve close command to said electric circuit to close the valve element and close the fuel injection valve, and adjusts the interval between the timing of outputting the valve open command and the timing of outputting the valve close command based on the length of a valve open response delay in response to the valve open command when the fuel injection valve opens, and the length of a valve close response delay in response to the valve close command when the fuel injection valve closes, wherein the microcomputer makes the interval longer the longer the valve open response delay, and shortens the interval the longer the valve close response delay.

2. An internal combustion engine control device as described in claim 1, characterized in that in the fuel injection valve, the valve closing response delay length is longer than the valve opening response delay length, and the microcomputer shortens the interval as the difference between the valve closing response delay length and the valve opening response delay length increases.

3. An internal combustion engine control device as described in claim 1 or claim 1 or 2, characterized in that the microcomputer derives the valve opening response delay length and the valve closing response delay length based on an electrical signal indicating the voltage applied to the actuator and input to the microcomputer.

4. An internal combustion engine control device as described in claim 3, characterized in that the valve opening response delay length is the length of time from the time the microcomputer outputs the valve opening command to the time the voltage reaches a first threshold while decreasing, and the valve closing response delay length is the length of time from the time the microcomputer outputs the valve closing command to the time the voltage reaches a second threshold while decreasing.

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