JP2017210942A - Device and method for controlling engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for controlling an engine which can control fuel injection timing and ignition timing with a simple configuration even when failure or abnormality occurs in a crank angle sensor.SOLUTION: A control reference timer generation section for fixing a phase of a cam angle sensor in a position set in advance and generating a control reference timer in accordance with a cam angle period when the crank angle sensor is determined as abnormal by a crank angle sensor abnormality determination section extracts timing at which a crank angle is BTDC75°CA or BTDC05°CA, and resets the control reference timer.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an engine control apparatus and an engine control method for controlling an engine of a vehicle such as an automobile.

  Conventionally, an engine control device applied to a vehicle such as an automobile detects the rotational position of the engine based on a pulse signal output from a crank angle sensor provided on the crankshaft, and synchronizes with the detected rotational position. Various parameters such as fuel injection timing and ignition timing are controlled.

  However, in the conventional engine control device that detects the rotational position of the engine using only the crank angle sensor, it becomes impossible to accurately detect the rotational position of the engine when a failure or abnormality occurs in the crank angle sensor, There was a problem that the engine could not be controlled properly.

  Therefore, in order to solve such a problem, an engine control device that ensures detection of the rotational position of the engine even when a failure or abnormality occurs in the crank angle sensor has been disclosed (for example, Patent Documents). 1).

  The engine control device disclosed in Patent Document 1 includes a crank angle sensor and a cam angle sensor, and generates a simulated crank angle from an output signal of the cam angle sensor when a failure or abnormality occurs in the crank angle sensor. Thus, the detection of the rotational position of the engine is ensured.

  According to the engine control device disclosed in Patent Document 1, even if a failure or abnormality occurs in the crank angle sensor, engine control is performed by generating a simulated crank angle from the output signal of the cam angle sensor. Can continue.

Japanese Patent No. 3872828

  However, in the engine control device disclosed in Patent Document 1, it is necessary to obtain two signals of a simulated crankshaft signal and a simulated crankshaft reference signal when generating a simulated crank angle, and the configuration is complicated. There is a problem of becoming.

  The present invention has been made to solve the above-described problems. Even when a failure or abnormality occurs in the crank angle sensor, the fuel injection timing and the ignition timing can be controlled with a simple configuration. It is an object to obtain an engine control device and an engine control method that can be performed.

  An engine control apparatus according to the present invention includes a crank angle detection unit that detects a crank angle signal from a crank angle sensor, and a crank angle between a crank angle signal detected last time by the crank angle detection unit and a crank angle signal detected this time. A crank angle cycle calculation unit that calculates a cycle, a cam angle detection unit that detects a cam angle signal from a cam angle sensor, a cam angle signal that was previously detected by the cam angle detection unit, and a cam angle signal that is detected this time A cam angle period calculating unit for calculating a cam angle period, a crank angle sensor abnormality determining unit for determining abnormality of the crank angle sensor based on a crank angle signal from the crank angle sensor and a cam angle signal from the cam angle sensor; When the crank angle sensor abnormality determination unit determines that the crank angle sensor is abnormal, the cam angle sensor phase is set to a preset position. A control reference timer generator for fixing and generating a control reference timer according to the cam angle period, and a first timing calculator for calculating the fuel injection timing and the ignition timing based on the crank angle signal detected by the crank angle detector And a second timing calculation unit that calculates the fuel injection timing and the ignition timing by the control reference timer generated by the control reference timer generation unit, and the control reference timer generation unit has a crank angle of BTDC 75 ° CA or BTDC 05 °. The CA reference time is extracted and the control reference timer is reset.

  The engine control method according to the present invention includes a crank angle detection step for detecting a crank angle signal from a crank angle sensor, and a crank angle between a crank angle signal detected last time in the crank angle detection step and a crank angle signal detected this time. A crank angle cycle calculating step for calculating a cycle, a cam angle detecting step for detecting a cam angle signal from a cam angle sensor, a cam angle signal detected last time in the cam angle detecting step, and a cam angle signal detected this time A cam angle period calculating step for calculating a cam angle period; a crank angle sensor abnormality determining step for determining abnormality of the crank angle sensor based on a crank angle signal from the crank angle sensor and a cam angle signal from the cam angle sensor; If the crank angle sensor abnormality determination step determines that the crank angle sensor is normal, If the crank angle sensor is determined to be abnormal in the first control reference timer generation step for generating the control reference timer according to the crank angle cycle and the crank angle sensor abnormality determination step, the phase of the cam angle sensor is changed. A fuel injection timing and an ignition timing are fixed by a second control reference timer generation step for generating a control reference timer according to the cam angle period, and a crank angle signal detected in the crank angle detection step. And a second timing calculation step for calculating a fuel injection timing and an ignition timing by the control reference timer generated in the second control reference timer generation step, and a second control reference timer In the generation step, the timing of the crank angle BTDC 75 ° CA or BTDC 05 ° CA is extracted and the control base It is intended to re-set the timer.

According to the engine control device and the engine control method according to the present invention, when the crank angle sensor abnormality determination unit determines that the crank angle sensor is abnormal, the cam angle sensor is set to a preset position. The control reference timer generating unit that fixes and generates a control reference timer according to the cam angle period extracts the timing of the crank angle BTDC 75 ° CA or BTDC 05 ° CA and resets the control reference timer.
Therefore, even when a failure or abnormality occurs in the crank angle sensor, the fuel injection timing and ignition timing can be controlled with a simple configuration.

It is a block block diagram which shows the engine control apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the relationship between the pulse signal of the crank angle sensor and cam angle sensor in the engine control apparatus which concerns on Embodiment 1 of this invention, and the control reference | standard timer produced | generated by the control reference | standard timer production | generation part. It is a flowchart which shows operation | movement of the crank angle sensor abnormality determination part in the engine control apparatus which concerns on Embodiment 1 of this invention. 4 is a flowchart showing an operation of a control reference timer generation unit when a pulse signal of a crank angle sensor is detected in the engine control apparatus according to Embodiment 1 of the present invention. 4 is a flowchart showing an operation of a control reference timer generation unit when a pulse signal of a cam angle sensor is detected in the engine control apparatus according to Embodiment 1 of the present invention. It is a flowchart which shows the setting operation | movement of the control reference timer in the engine control apparatus which concerns on Embodiment 1 of this invention.

  Hereinafter, preferred embodiments of an engine control device and an engine control method according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.

  Note that the engine control device and the engine control method according to the present invention provide fuel injection by the cam angle signal from the cam angle sensor even when the crank angle sensor is broken or abnormal and the crank angle signal is interrupted. The engine stall is prevented by appropriately controlling the timing and ignition timing.

Embodiment 1 FIG.
1 is a block diagram showing an engine control apparatus according to Embodiment 1 of the present invention. In FIG. 1, the engine control device is configured by an ECU (Electronic Control Unit) 100 and is connected to a crank angle sensor 1 and a cam angle sensor 2.

  The ECU 100 includes an input circuit 101 and a microcomputer 110. The microcomputer 110 includes a crank angle detection unit 111, a crank angle cycle calculation unit 112, a cam angle detection unit 113, a cam angle cycle calculation unit 114, a crank angle sensor abnormality determination unit 115, a control reference timer generation unit 116, and a first timing calculation unit. 117, a second time calculation unit 118, and a device driving unit 119.

  The microcomputer 110 includes a CPU (Central Processing Unit) that executes arithmetic processing, a ROM (Read Only Memory) that stores program data and fixed value data, and a RAM (RAM) that sequentially updates and rewrites stored data. Random Access Memory), and each block of the microcomputer 110 is stored in the ROM as software.

  The pulse signal output from the crank angle sensor 1 and the pulse signal output from the cam angle sensor 2 are respectively input to the input circuit 101 of the ECU 100. The input circuit 101 outputs the input pulse signal from the crank angle sensor 1 and pulse signal from the cam angle sensor 2 to the microcomputer 110.

  The crank angle detector 111 detects that the pulse signal of the crank angle sensor 1 is input from the input circuit 101 to the microcomputer 110 and stores the time. The crank angle cycle calculation unit 112 calculates a cycle between 10 ° CA (crank angle) from the difference between the input time of the current pulse signal stored in the crank angle detection unit 111 and the input time of the previous pulse signal. .

  Further, the crank angle cycle calculation unit 112, when the crank angle signal position is BTDC (Before Top Dead Center) 05 ° CA or BTDC 75 ° CA, the previous BTDC 05 ° CA or BTDC 75 ° CA The period between 180 ° CA is calculated based on the difference from the time.

  The cam angle detector 113 detects that the pulse signal of the cam angle sensor 2 is input from the input circuit 101 to the microcomputer 110 and stores the time. The cam angle period calculation unit 114 calculates a period between 360 ° CA from the difference between the current pulse signal input time stored in the cam angle detection unit 113 and the previous pulse signal input time.

  The crank angle sensor abnormality determination unit 115 is based on the state of the pulse signal of the crank angle sensor 1 detected by the crank angle detection unit 111 and the state of the pulse signal of the cam angle sensor 2 detected by the cam angle detection unit 113. Thus, the failure or abnormality of the crank angle sensor 1 is determined.

  When the crank angle sensor abnormality determination unit 115 determines that the crank angle sensor 1 is normal, the control reference timer generation unit 116 has a cycle between 180 ° CA calculated by the crank angle cycle calculation unit 112. Then, a control reference timer is generated.

  On the other hand, when the crank angle sensor abnormality determining unit 115 determines that the crank angle sensor 1 is malfunctioning or abnormal, the control reference timer generating unit 116 calculates 360 ° calculated by the cam angle period calculating unit 114. A control reference timer is generated from the period between CAs.

  When the crank angle sensor abnormality determination unit 115 determines that the crank angle sensor 1 is normal, the first timing calculation unit 117 determines that the crank angle detection unit 111 has a crank angle signal position of BTDC05 ° CA or BTDC 75 °. When CA is detected, the injector injection start timing, injection end timing, ignition coil energization start timing, and energization end timing are calculated.

  On the other hand, when the crank angle sensor abnormality determination unit 115 determines that the crank angle sensor 1 is malfunctioning or abnormal, the second timing calculation unit 118 controls the control reference timer generated by the control reference timer generation unit 116. Then, BTDC05 ° CA or BTDC 75 ° CA of the crank angle signal position is estimated, and the injector injection start timing, injection end timing, ignition coil energization start timing, and energization end timing are calculated.

  When the crank angle sensor abnormality determination unit 115 determines that the crank angle sensor 1 is normal, the device driving unit 119 performs the injector injection start timing and injection end calculated by the first timing calculation unit 117. Based on the timing, the energization start timing of the ignition coil, and the energization end timing, a signal for driving the injector and the ignition coil is output.

  On the other hand, when the crank angle sensor abnormality determining unit 115 determines that the crank angle sensor 1 is malfunctioning or abnormal, the device driving unit 119 starts injection of the injector calculated by the second timing calculating unit 118. Based on the timing, the injection end timing, the energization start timing of the ignition coil, and the energization end timing, a signal for driving the injector and the ignition coil is output.

  Next, the relationship between the pulse signals of the crank angle sensor 1 and the cam angle sensor 2 shaped by the input circuit 101 and the control reference timer generated by the control reference timer generation unit 116 will be described with reference to FIG. .

  In FIG. 2, the output signal of the crank angle sensor 1 is a pulse signal with a cycle of 10 ° CA. In order to define the BTDC 75 ° CA of the crank angle signal position, the signal before the crank angle signal of BTDC 85 ° CA is One pulse or two pulses are omitted.

  When the current crank angle signal position is BTDC05 ° CA or BTDC75 ° CA, the crank angle cycle calculation unit 112 is 180 ° CA from the previous crank angle signal input time of BTDC05 ° CA or BTDC75 ° CA. Calculate the period.

  Here, when the crank angle sensor 1 is normal, the control reference timer generation unit 116 sets the control reference timer when the crank angle signal position is BTDC05 ° CA or BTDC 75 ° CA. The control reference timer is set based on the calculated period between 180 ° CA.

  More specifically, when the current crank angle signal position is BTDC05 ° CA, up to BTDC 75 ° CA + α ° CA, and when the current crank angle signal position is BTDC 75 ° CA, up to BTDC 05 ° CA + α ° CA. Time. Α ° CA is a margin angle, and is a small value such as 10 ° CA.

  The control reference timer is decremented by 1 for each reference time, and when the timer value reaches 0, a software interrupt is generated by the microcomputer function. An input of BTDC 05 ° CA or BTDC 75 ° CA of the angular signal position is generated, and the timer is reset.

  In addition, in order to prevent a software interruption by the control reference timer due to a variation in the crank angle sensor period due to a rotation variation, every time a crank angle signal is detected, 10 ° CA between the latest crank angle signals is detected. The control reference timer is reviewed from the cycle.

  Therefore, when the crank angle sensor 1 is normal, the value of the control reference timer does not become 0, and the second timing calculation unit 118 erroneously starts the injection start timing, the injection end timing, and the ignition coil timing. The power supply start time and the power supply end time are not calculated.

  The cam angle signal is a signal that repeats high and low every 360 ° CA, and the cam angle cycle calculation unit 114 is 360 for every input of the cam angle signal regardless of whether the crank angle sensor 1 is normal or abnormal. Calculate the period between ° C. Further, the cam angle cycle calculation unit 114 calculates the time of BTDC05 ° CA to BTDC75 ° CA and the time of BTDC75 ° CA to BTDC05 ° CA, which are set values of the control reference timer, from the cycle between 360 ° CA.

  Here, when the crank angle sensor 1 fails or becomes abnormal, the control reference timer cannot be set by the crank angle signal, so the value of the control reference timer becomes zero. At this time, the second timing calculation unit 118 calculates the injection start timing, injection end timing, energization start timing, and energization end timing of the ignition coil. Based on the calculation results, the device drive unit 119 performs the injector and ignition. Outputs the coil drive signal.

  Further, when the value of the control reference timer becomes 0, the time from BTDC05 ° CA to BTDC75 ° CA obtained from the cycle between 360 ° CA calculated by the cam angle cycle calculation unit 114, or BTDC75 ° The time from CA to BTDC05 ° CA is set in the control reference timer.

  When the crank angle sensor 1 fails or becomes abnormal, the control reference timer calculates the time from the cycle between 360 ° CA calculated by the cam angle cycle calculation unit 114 to the next BTDC 75 ° CA. The control reference timer error due to rotation fluctuation is corrected.

  Hereinafter, the operation of the control reference timer of the engine control apparatus according to the first embodiment of the present invention will be described in detail with reference to the flowcharts of FIGS. FIG. 3 is a flowchart showing the operation of the crank angle sensor abnormality determination unit in the engine control apparatus according to Embodiment 1 of the present invention.

  In FIG. 3, first, the crank angle sensor abnormality determination unit 115 determines whether or not a crank angle signal is detected by the crank angle detection unit 111 within a preset predetermined time (step S101).

  If it is determined in step S101 that a crank angle signal has been detected within a predetermined time (ie, Yes), the crank angle sensor abnormality determination unit 115 determines that the crank angle sensor 1 is normal, and The angle sensor abnormality flag is cleared (step S102), and the process of FIG.

  On the other hand, if it is determined in step S101 that the crank angle signal is not detected within the predetermined time (that is, No), the crank angle sensor abnormality determining unit 115 performs camming within the same predetermined time as in step S101. It is determined whether or not a cam angle signal is detected by the angle detector 113 (step S103).

  If it is determined in step S103 that the cam angle signal has been detected within the predetermined time (that is, Yes), the crank angle sensor abnormality determination unit 115 determines that the crank angle sensor 1 is malfunctioning or abnormal. Then, the crank angle sensor abnormality flag is set (step S104), and the processing of FIG.

  On the other hand, if it is determined in step S103 that the cam angle signal has not been detected within the predetermined time (ie, No), the crank angle sensor abnormality determination unit 115 ends the process of FIG. 3 as it is.

  FIG. 4 is a flowchart showing the operation of the control reference timer generation unit when a pulse signal of the crank angle sensor is detected in the engine control apparatus according to Embodiment 1 of the present invention.

  In FIG. 4, the control reference timer generator 116 first determines whether or not the crank angle sensor abnormality flag is set (step S201). This crank angle sensor abnormality flag is set or reset in step S102 or step S104 of FIG.

  If it is determined in step S201 that the crank angle sensor abnormality flag is set (that is, No), the control reference timer generation unit 116 ends the process of FIG. 4 as it is.

  On the other hand, if it is determined in step S201 that the crank angle sensor abnormality flag is not set (that is, Yes), it is determined whether or not the current crank angle signal position is BTDC 75 ° CA (step S202). ).

  If it is determined in step S202 that the current crank angle signal position is BTDC 75 ° CA (ie, Yes), the control reference timer generation unit 116 determines the current BTDC 75 ° CA signal input time and the previous BTDC 75. The period between 180 ° CA is calculated from the difference from the signal input time of ° CA (step S203).

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from BTDC 75 ° CA to ATDC (after top dead center) 05 ° CA from the cycle between 180 ° CA (step S204).

  Next, the control reference timer generator 116 updates the previous signal input time of BTDC 75 ° CA to the current signal input time of BTDC 75 ° CA (step S205).

  Thereafter, the control reference timer generation unit 116 updates the previous crank angle signal input time to the current crank angle signal input time (step S206), and sets the predicted time from BTDC 75 ° CA to ATDC 05 ° CA in the control reference timer. After setting (step S207), the process of FIG. 4 ends.

  On the other hand, when it is determined in step S202 that the current crank angle signal position is not BTDC 75 ° CA (ie, No), the control reference timer generation unit 116 has the current crank angle signal position BTDC 05 ° CA. It is determined whether or not (step S208).

  If it is determined in step S208 that the current crank angle signal position is BTDC05 ° CA (ie, Yes), the control reference timer generation unit 116 determines the current BTDC 05 ° CA signal input time and the previous BTDC 05. The period between 180 ° CA is calculated from the difference from the signal input time of ° CA (step S209).

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from BTDC05 ° CA to BTDC65 ° CA from the cycle between 180 ° CA (step S210).

  Next, the control reference timer generator 116 updates the previous signal input time of BTDC05 ° CA to the current signal input time of BTDC05 ° CA (step S211).

  Thereafter, the control reference timer generation unit 116 updates the previous crank angle signal input time to the current crank angle signal input time (step S206), and sets the predicted time from BTDC05 ° CA to BTDC65 ° CA in the control reference timer. After setting (step S207), the process of FIG. 4 ends.

  On the other hand, if it is determined in step S208 that the current crank angle signal position is not BTDC05 ° CA (ie, No), the control reference timer generating unit 116 has the current crank angle signal position being BTDC 85 ° CA. It is determined whether or not (step S212).

  If it is determined in step S212 that the current crank angle signal position is BTDC 85 ° CA (ie, Yes), the control reference timer generation unit 116 has two or three cylinders of the current engine. It is determined whether or not (step S213).

  When it is determined in step S213 that the cylinder of the current engine is 2 cylinders or 3 cylinders (that is, Yes), the control reference timer generation unit 116 determines the current crank angle signal input time and the previous crank angle. By dividing the difference from the signal input time by 3, the period between 10 ° CA is calculated (step S214).

  Here, this calculation has a configuration in which the signal before the crank angle signal of BTDC 85 ° CA is missed by two pulses in order to detect the crank angle signal position, and the current crank angle signal and the previous crank angle signal This is because the interval of 30 ° CA.

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from the current crank angle signal position to BTDC 65 ° CA from a cycle between 10 ° CA (step S215).

  After that, the control reference timer generation unit 116 updates the previous crank angle signal input time to the current crank angle signal input time (step S206), and the control reference timer stores the current crank angle signal position to BTDC 65 ° CA. An estimated time is set (step S207), and the process of FIG. 4 is terminated.

  On the other hand, when it is determined in step S213 that the cylinder of the current engine is not two or three cylinders (that is, No), the control reference timer generation unit 116 determines the current crank angle signal input time and the previous crank angle. A period between 10 ° CA is calculated by dividing the difference from the angle signal input time by 2 (step S216).

  Here, this calculation is configured so that one pulse is missing from the signal before the crank angle signal of BTDC 85 ° CA in order to detect the crank angle signal position, and the current crank angle signal, the previous crank angle signal, This is because the interval of 20 ° CA.

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from the current crank angle signal position to BTDC 65 ° CA from a cycle between 10 ° CA (step S217).

  After that, the control reference timer generation unit 116 updates the previous crank angle signal input time to the current crank angle signal input time (step S206), and the control reference timer stores the current crank angle signal position to BTDC 65 ° CA. An estimated time is set (step S207), and the process of FIG. 4 is terminated.

  On the other hand, when it is determined in step S212 that the current crank angle signal position is not BTDC 85 ° CA (ie, No), the control reference timer generation unit 116 determines that the current crank angle signal position is BTDC 65 ° CA to BTDC 15. It is determined whether or not it is CA (step S218).

  If it is determined in step S218 that the current crank angle signal position is BTDC65 ° CA to BTDC 15 ° CA (ie, Yes), the control reference timer generation unit 116 determines the current crank angle signal input time and the previous time. A period between 10 ° CA is calculated from the difference from the crank angle signal input time (step S219).

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from the current crank angle signal position to ATDC 05 ° CA from a cycle between 10 ° CA (step S220).

  Thereafter, the control reference timer generation unit 116 updates the previous crank angle signal input time to the current crank angle signal input time (step S206), and the control reference timer sets the current crank angle signal position to ATDC05 ° CA. An estimated time is set (step S207), and the process of FIG. 4 is terminated.

  On the other hand, if it is determined in step S218 that the current crank angle signal position is not BTDC 65 ° CA to BTDC 15 ° CA (ie, No), the control reference timer generation unit 116 determines that the current crank angle signal input time and A period between 10 ° CA is calculated from the difference from the previous crank angle signal input time (step S221).

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from the current crank angle signal position to BTDC 65 ° CA from a cycle between 10 ° CA (step S222).

  After that, the control reference timer generation unit 116 updates the previous crank angle signal input time to the current crank angle signal input time (step S206), and the control reference timer stores the current crank angle signal position to BTDC 65 ° CA. An estimated time is set (step S207), and the process of FIG. 4 is terminated.

  Thus, by setting the control reference timer to BTDC 65 ° CA or ATDC 05 ° CA, it is possible to prevent the control reference timer from being accidentally subtracted to 0 when the crank angle sensor 1 is normal. .

  Further, by adjusting the control reference timer every 10 ° CA, it is possible to prevent the control reference timer from being accidentally subtracted to 0 even when the rotational speed changes suddenly.

  FIG. 5 is a flowchart showing the operation of the control reference timer generation unit when a pulse signal of the cam angle sensor is detected in the engine control apparatus according to Embodiment 1 of the present invention.

  In FIG. 5, first, the control reference timer generator 116 calculates a period between 360 ° CA from the difference between the current cam angle signal input time and the previous cam angle signal input time (step S301). The cam angle signal input time is updated with the current cam angle signal input time (step S302).

  Subsequently, the control reference timer generation unit 116 calculates a predicted time from BTDC 75 ° CA to BTDC 05 ° CA from the cycle between 360 ° CA (step S303), and from the cycle between 360 ° CA, BTDC 05 ° CA˜ The predicted time up to BTDC 75 ° CA is calculated (step S304).

  Next, the control reference timer generator 116 determines whether or not the crank angle sensor abnormality flag is set (step S305). This crank angle sensor abnormality flag is set or reset in step S102 or step S104 of FIG.

  In step S305, when it is determined that the crank angle sensor abnormality flag is set (that is, Yes), the control reference timer generation unit 116 fixes the phase of the cam angle sensor 2 at a predetermined position set in advance. (Step S306).

  Subsequently, the control reference timer generation unit 116 calculates the predicted time from the cam angle signal detection timing to BTDC 75 ° CA from the period between 360 ° CA calculated in step S301 (step S307), This estimated time is set (step S308), and the process of FIG. 5 is terminated.

  On the other hand, if it is determined in step S305 that the crank angle sensor abnormality flag is not set (that is, No), the control reference timer generation unit 116 ends the process of FIG. 5 as it is.

  Here, the cam angle signal is a signal that switches between high and low at ATDC 25 ° CA, and becomes ATDC 25 ° CA when the cam angle signal is input. For this reason, even when the timing at which the control reference timer becomes 0 due to engine rotation fluctuation has an error with respect to the actual crank angle BTDC05 ° CA or BTDC 75 ° CA, the engine The error of the control reference timer due to the rotation fluctuation can be corrected.

  FIG. 6 is a flowchart showing the setting operation of the control reference timer in the engine control apparatus according to Embodiment 1 of the present invention.

  In FIG. 6, first, the control reference timer generation unit 116 determines whether or not the timing when the current control reference timer becomes 0 is BTDC 75 ° CA (step S401).

  In step S401, when it is determined that the timing when the current control reference timer becomes 0 is BTDC 75 ° CA (that is, Yes), the control reference timer generation unit 116 calculates in step S303 of FIG. The predicted time from BTDC 75 ° CA to BTDC 05 ° CA is set in the control reference timer (step S402).

  Subsequently, the second timing calculation unit 118 calculates the injector injection start timing, injection end timing, ignition coil energization start timing, energization end timing from the control reference timer generated by the control reference timer generation unit 116, Based on the calculation result, the device drive unit 119 outputs drive signals for the injector and the ignition coil (step S403), and the process of FIG. 6 is terminated.

  On the other hand, in step S401, when it is determined that the timing when the current control reference timer becomes 0 is not BTDC 75 ° CA (ie, No), the control reference timer generation unit 116 performs step S304 in FIG. The calculated predicted time from BTDC05 ° CA to BTDC75 ° CA is set in the control reference timer (step S404).

  Subsequently, the second timing calculation unit 118 calculates the injector injection start timing, injection end timing, ignition coil energization start timing, energization end timing from the control reference timer generated by the control reference timer generation unit 116, Based on the calculation result, the device driving unit 119 outputs drive signals for the injector and the ignition coil (step S405), and the process of FIG. 6 is terminated.

  As a result, even when the crank angle sensor 1 fails or becomes abnormal, the fuel injection timing and ignition timing can be appropriately controlled by the control reference timer.

As described above, according to the first embodiment, when the crank angle sensor abnormality determination unit determines that the crank angle sensor is abnormal, the phase of the cam angle sensor is fixed at a preset position. At the same time, a control reference timer generating unit that generates a control reference timer according to the cam angle period extracts the timing of the crank angle BTDC 75 ° CA or BTDC 05 ° CA and resets the control reference timer.
Therefore, even when a failure or abnormality occurs in the crank angle sensor, the fuel injection timing and ignition timing can be controlled with a simple configuration.

In addition, the control reference timer generator generates a cam angle cycle when the crank angle sensor abnormality determination unit determines that the crank angle sensor is abnormal, and when the cam angle signal is detected next by the cam angle sensor. Correct the control reference timer accordingly.
Therefore, the accuracy of the control reference timer can be improved.

The control reference timer generation unit generates the control reference timer according to the crank angle cycle even when the crank angle sensor abnormality determination unit determines that the crank angle sensor is normal.
Therefore, at the time of transition from the control of the fuel injection timing and ignition timing when the crank angle sensor is normal to the control of the fuel injection timing and ignition timing at the time of abnormality, the control of the fuel injection timing and ignition timing is not lost It is possible to switch to control of the fuel injection timing and ignition timing by.

  DESCRIPTION OF SYMBOLS 1 Crank angle sensor, 2 Cam angle sensor, 101 Input circuit, 110 Microcomputer, 111 Crank angle detection part, 112 Crank angle period calculation part, 113 Cam angle detection part, 114 Cam angle period calculation part, 115 Crank angle sensor abnormality determination part , 116 Control reference timer generation unit, 117 First timing calculation unit, 118 Second timing calculation unit, 119 Device driving unit.

Claims (4)

A crank angle detector for detecting a crank angle signal from the crank angle sensor;
A crank angle cycle calculation unit for calculating a crank angle cycle between the crank angle signal detected last time by the crank angle detection unit and the crank angle signal detected this time;
A cam angle detector for detecting a cam angle signal from the cam angle sensor;
A cam angle cycle calculation unit that calculates a cam angle cycle between the cam angle signal detected last time by the cam angle detection unit and the cam angle signal detected this time;
A crank angle sensor abnormality determination unit that determines abnormality of the crank angle sensor based on a crank angle signal from the crank angle sensor and a cam angle signal from the cam angle sensor;
When the crank angle sensor abnormality determining unit determines that the crank angle sensor is abnormal, the cam angle sensor phase is fixed at a preset position and controlled according to the cam angle cycle. A control reference timer generator for generating a reference timer;
A first timing calculation unit that calculates a fuel injection timing and an ignition timing based on a crank angle signal detected by the crank angle detection unit;
A second timing calculation unit that calculates a fuel injection timing and an ignition timing by the control reference timer generated by the control reference timer generation unit,
The control reference timer generation unit is an engine control device that extracts a timing of a crank angle BTDC 75 ° CA or BTDC 05 ° CA and resets the control reference timer. When the crank angle sensor abnormality determination unit determines that the crank angle sensor is abnormal, the control reference timer generation unit detects the cam angle signal when the cam angle signal is detected next by the cam angle sensor. The engine control apparatus according to claim 1, wherein the control reference timer is corrected according to an angular period. The control reference timer generation unit generates a control reference timer according to the crank angle cycle when the crank angle sensor abnormality determination unit determines that the crank angle sensor is normal. The engine control apparatus according to claim 2. A crank angle detection step for detecting a crank angle signal from the crank angle sensor;
A crank angle period calculating step for calculating a crank angle period between the crank angle signal detected last time in the crank angle detecting step and the crank angle signal detected this time;
A cam angle detecting step for detecting a cam angle signal from the cam angle sensor;
A cam angle cycle calculating step for calculating a cam angle cycle between the cam angle signal detected last time in the cam angle detecting step and the cam angle signal detected this time;
A crank angle sensor abnormality determination step for determining abnormality of the crank angle sensor based on a crank angle signal from the crank angle sensor and a cam angle signal from the cam angle sensor;
A first control reference timer generating step for generating a control reference timer according to the crank angle cycle when the crank angle sensor abnormality determining step determines that the crank angle sensor is normal;
When the crank angle sensor abnormality determining step determines that the crank angle sensor is abnormal, the phase of the cam angle sensor is fixed at a preset position, and the cam angle sensor determines the phase according to the cam angle cycle. A second control reference timer generating step for generating a control reference timer;
A first timing calculation step of calculating a fuel injection timing and an ignition timing based on the crank angle signal detected in the crank angle detection step;
A second timing calculating step of calculating a fuel injection timing and an ignition timing by the control reference timer generated in the second control reference timer generating step,
An engine control method for extracting the timing of a crank angle BTDC 75 ° CA or BTDC 05 ° CA and resetting the control reference timer in the second control reference timer generation step.

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