Fuel injection valve control device

Abstract

To provide a fuel injection valve control device capable of avoiding wrong erroneous diagnosis in multi-stage injection control.SOLUTION: A fuel injection valve control device for controlling a fuel injection valve for injecting fuel into an internal combustion engine by an injection command includes an arithmetic processing unit for executing a program regarding control for the fuel injection valve, and a circuit for driving the fuel injection valve according to the control command, the arithmetic processing unit includes an open / close valve detection part for detecting open / close state of the fuel injection valve, and a determination part for determining anomaly of drive timing for the fuel injection valve according to drive timing of the fuel injection valve by the control command and the open / close state detection signal of the fuel injection valve detected by the open / close valve detection part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a fuel injection valve control device that controls a fuel injection valve of an in-cylinder direct injection internal combustion engine that directly injects fuel into a cylinder.

Background Art

[0002] In recent years, as a measure to improve the exhaust performance of internal combustion engines, multi-stage injection control that performs fuel injection at least once or more during one combustion cycle has been carried out. In this multi-stage injection control, fuel injection is executed after being divided based on the number of multi-stage injections required from the operating state of the internal combustion engine and the like.

[0003] Also, the fuel injection amount calculation during the execution of multi-stage injection control treats the fuel injection amount calculated by a conventional calculation formula as the total injection amount, and drives and controls the fuel injection valve with the fuel injection amount for each multi-stage injection obtained by dividing this total injection amount by a division ratio based on the number of multi-stage injections.

[0004] When multi-stage injection control is executed, the actual number of injection times and valve opening timing executed by the fuel injection valve may not match the command value and drive timing of the number of multi-stage injections, and it may remain undetected that there is an abnormality in the multi-stage injection control, resulting in the possibility that the expected value of the exhaust performance cannot be satisfied.

[0005] In multi-stage injection control, multi-stage injection diagnosis capable of detecting the above abnormality has been proposed.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, conventionally, due to the adaptation of multi-stage injection control to all engine speeds and to reduce the load on the arithmetic processing unit, multi-stage injection diagnosis has not been performed in real time, and a method of performing diagnosis at a fixed cycle has been introduced.

[0008] Also, due to the functions and operation methods of the arithmetic processing unit, the drive timing information of fuel injection and the detected execution injection timing are often defined in different units. To cope with this, in timing anomaly determination, it is necessary to align the two timings to the same unit before determination.

[0009] In addition, since the method of performing diagnosis at a fixed cycle is used, in regions where the engine speed changes greatly, such as in the high-speed range or during transient rotation, as the accuracy of unit conversion decreases, the accuracy of timing anomaly determination decreases, and in some cases, there is a problem of misjudging anomaly detection diagnosis.

[0010] The present invention is made to solve the above problems, and an object thereof is to provide a fuel injection valve control device capable of avoiding misdiagnosis of multi-stage injection control by improving the accuracy of timing anomaly determination of multi-stage injection control.

Means for Solving the Problems

[0011] In order to solve the above problems, the present invention is a fuel injection valve control device that controls a fuel injection valve for injecting fuel into an internal combustion engine by an injection command, and includes an arithmetic processing unit that executes a program related to the control of the fuel injection valve, and a circuit that drives the fuel injection valve in response to the control command. The arithmetic processing unit includes an open / close valve detection unit that detects the open / close state of the fuel injection valve, and a determination unit that determines an anomaly in the drive timing of the fuel injection valve according to the drive timing of the fuel injection valve by the control command and the open / close state detection signal of the fuel injection valve detected by the open / close valve detection unit. Then, based on the acquisition timing of the injection command and the period of the injection command, the acquisition timing of the detection result of the on-off valve detection unit is set to a multiple of the period do.

Effects of the Invention

[0012] According to the present invention, it is possible to guarantee the actual operation of the multi-stage injection control and to guarantee the exhaust performance.

[0013] Problems, configurations, operations, and effects of the present invention other than those described above will be clarified by the following description of the embodiments.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described in detail with appropriate reference to the drawings.

[0016] The fuel injection control device according to this embodiment relates to an abnormality detection control for multi-stage injection control, and is constructed to operate in the same cycle as the fuel injection control. For each cylinder of the engine, a multiple of the cycle (in the case of a four-cycle internal combustion engine, a multiple of 2 or 4 is desirable) is set as one diagnosis area, and using the elapsed time of a certain rotation angle triggered by the crank signal in the diagnosis area, the timing of the control command for controlling the drive of the fuel injection valve is aligned with the timing when the valve opening operation of the fuel injection valve is detected, so it is converted from an angle to time, and it is characterized by detecting whether the drive timing of the fuel injection valve after the unit conversion and the timing when the valve opening operation of the fuel injection valve is detected are within a predetermined range.

[0017] Figure 1 is a block diagram showing the basic configuration of a fuel injection control device according to an embodiment of the present invention. First, the battery voltage 110 supplied from the battery 103 is supplied to a fuel injection valve control device 101 provided in an ECM (not shown) via a fuse (not shown) and a relay (not shown). ECM is an abbreviation for Engine Control Module.

[0018] The fuel injection valve control device 101 includes a high voltage generation unit 104. The high voltage generation unit 104 generates a high power supply voltage (hereinafter referred to as "high voltage") 109 required for the valve body of the fuel injection valve 108 to perform a valve opening operation even in a state where the valve body provided in the fuel injection valve 108 is under a high fuel pressure (hereinafter referred to as "high fuel pressure") from the battery voltage 110.

[0019] The high voltage generation unit 104 boosts the battery voltage 110 to a preset target high voltage based on a command from the drive IC 105. The fuel injection valve control device 101 applies the high voltage 109 generated by the high voltage generation unit 104 at the start of the operation of the fuel injection valve 108, so that the valve body in the fuel injection valve 108 can obtain an opening force that overcomes the strong closing force generated by the high-pressure fuel pressure.

[0020] Further, the drive IC 105 performs current control by controlling the fuel injection valve drive units 106 and 107 in a predetermined sequence based on the drive time (pulse signal 114) of the fuel injection valve 108 input from the microcomputer 102 and the drive current set value 115 of the fuel injection valve 108. The microcomputer 102 is an example of an arithmetic processing unit that executes a program.

[0021] In addition, in FIG. 1, an example in which the microcomputer 102 and the drive IC 105 are mounted in the same fuel injection valve control device 101 is shown. However, the microcomputer 102 and the drive IC 105 may be mounted in separate devices and connected by a communication line.

[0022] The pulse signal 114 and the drive current set value 115 of the fuel injection valve are calculated inside the microcomputer 102. Specifically, they are provided as a program in the memory inside the microcomputer 102 or a memory (not shown). The multi-stage injection control calculation unit 102a executed by the microcomputer 102 determines whether or not to execute multi-stage injection from the operating state or operating scene of the internal combustion engine. When multi-stage injection control is permitted, the number of multi-stage injections, the division ratio of the fuel injection amount, and each injection timing are calculated by a predetermined arithmetic formula. Naturally, when it is determined that multi-stage injection control is prohibited, the conventional drive arithmetic processing of the fuel injection valve 108 that performs fuel injection only once during one combustion cycle is performed.

[0023] The multi-stage injection control calculation unit 102a calculates the number of multi-stage injections, the division ratio, and further the drive timing of the fuel injection valve 108 calculated by a predetermined procedure, in addition to the fuel injection amount determined from the operating state of the internal combustion engine, and outputs the drive timing information 113 to the fuel injection valve pulse signal calculation unit 102b.

[0024] The fuel injection valve pulse signal calculation unit 102b calculates the fuel injection amount for each injection performed multiple times during multi-stage injection control (for example, divides the fuel injection amount by the division ratio), generates the pulse signal 114 for each fuel injection valve 108 provided in the internal combustion engine, and outputs it to the drive IC 105.

[0025] Further, the fuel injection valve drive waveform command unit 102c outputs the drive current set value 115 of the fuel injection valve 108 determined from information 111 such as the operating state of the internal combustion engine and the fuel pressure to the drive IC 105.

[0026] By these drive controls, when the valve body of the fuel injection valve 108 performs an operation from valve opening to valve closing, the pulse signal 114 and the drive current of the fuel injection valve are input to the valve opening / closing detection unit 102h. Thus, the valve opening / closing detection unit 102h detects whether the fuel injection valve 108 is in the state of valve opening, valve closing, or both valve opening and closing. The valve opening / closing detection unit 102h outputs the detection result as a pulse-shaped signal. A detailed description of the valve opening / closing detection unit 102h will be given later with reference to FIG. 3.

[0027] The information 116 output by the valve opening / closing detection unit 102h is input to the actual injection number determination unit 102g and the actual injection timing determination unit 102f. The actual injection number determination unit 102g and the actual injection timing determination unit 102f determine whether the fuel injection valve 108 has operated normally or has had an abnormal operation based on whether a predetermined condition is satisfied, and based on this result, they total the number of normally operated injection times and injection timings, as well as the number of injection times and injection timings with abnormalities.

[0028] The actual injection number determination unit 102g determines whether the multi-stage injection control is normal based on whether the valve opening detection number result based on the information 116 from the valve opening / closing detection unit 102h matches the commanded injection number 112 calculated by the multi-stage injection control calculation unit 102a. The actual injection number determination unit 102g outputs the information 117 of the determination result to the multi-stage injection normal determination unit 102d.

[0029] Further, when the multi-stage injection normal determination unit 102d determines that the valve opening detection number result based on the information 116 from the valve opening / closing detection unit 102h does not match the commanded injection number 112 calculated by the multi-stage injection control calculation unit 102a, it determines that this is an abnormality in which an error in the fuel injection amount has occurred because the fuel injection amount required by the internal combustion engine is not satisfied.

[0030] The execution injection timing determination unit 102f determines whether the multi-stage injection control is normal based on whether the difference between the valve opening detection timing information from the on-off valve detection unit 102h and the drive timing information 119 of the fuel injection valve 108 converted by the drive timing unit conversion unit 102e converges within a predetermined range. The execution injection timing determination unit 102f outputs the determination result information 118 to the multi-stage injection normal determination unit 102d.

[0031] Also, when the difference between the valve opening detection timing information from the on-off valve detection unit 102h and the drive timing information 119 of the fuel injection valve 108 converted by the drive timing unit conversion unit 102e does not converge within a predetermined range, the multi-stage injection normal determination unit 102d determines that it is an abnormality because the fuel injection timing required by the internal combustion engine is not satisfied and the fuel cannot be optimally burned.

[0032] The drive timing unit conversion unit 102e is a unit conversion unit for enabling comparison of the drive timing information of the valve opening detection timing information from the on-off valve detection unit 102h and the drive timing information 113 of the fuel injection valve 108 in the same unit. The drive timing unit conversion unit 102e uses the drive timing information of the drive timing information 113 calculated by the multi-stage injection control arithmetic unit 102a and the elapsed time 120 per constant angle calculated by a crank signal processing device (not shown) to convert the drive timing information of the drive timing information 113 of the fuel injection valve 108 from an angle to time. The description of the drive timing unit conversion unit 102e will be described later with reference to FIG. 5.

[0033] Of course, FIG. 1 is a diagram with a simplified actual configuration for convenience of explanation. For example, conventionally, the pulse signal 114 is generally provided for each fuel injection valve provided in the internal combustion engine. Similarly, since the number of injection times, split ratio, injection timing, etc. related to the multi-stage injection control also change over time, it is desirable to process each cylinder.

[0034] Similarly, information 116 calculated by the on-off valve detection unit 102h, information 117 of the determination result of the execution injection number determination unit 102g, information 118 of the determination result of the execution injection timing determination unit 102f, drive timing information 119 by the drive timing unit conversion unit 102e, command injection number 112, drive timing information 113, etc. are provided for each cylinder.

[0035] In addition, in this figure, an example is shown in which the on-off valve detection unit 102h is arranged in the microcomputer 102. However, in recent years, with the evolution of the drive IC 105, there is a drive IC 105 having an arithmetic processing unit that executes a program, similar to the microcomputer 102. In a fuel injection valve control device that employs these, the on-off valve detection unit 102h may be arranged on the drive IC 105 side, and the on-off valve detection result may be output to the microcomputer 102.

[0036] Next, multi-stage injection control will be described. FIG. 2 is a time chart showing a pulse signal 114 when switching from single injection, which is a conventional injection control, to multi-stage injection. T201 shown in FIG. 2 indicates the point in time when multi-stage injection control is permitted.

[0037] First, not limited to the fuel injection valve 108, as a general method of so-called angle control that performs architecture drive based on a predetermined crank angle, control reference positions (T208a to T208d) for each cylinder are provided, and based on this control reference position (T208a to T208d), the timing of the architecture operation is measured at a desired angle.

[0038] Based on this, explaining FIG. 2, before T201 (to the left of T201 in FIG. 2), multi-stage injection control is prohibited, and normal single injection is executed (injection execution signals 202 and 203). Further, for T201, the injection execution signal 204 in the future (to the right of T201 in FIG. 2) has a control reference position to the left of T201, and at this point, injection control is executed based on the injection timing 209 at this time, so this is also single injection.

[0039] On the other hand, from T201 to T208b which is the first control reference position, an injection command 205 occurs at the injection timing 210 for multi-stage injection. Therefore, multi-stage injection is executed from here. Thereafter, the multi-stage injection control is continued, and by performing the same control as the injection command 205, the injection commands 206 and 207 also execute multi-stage injection.

[0040] Note that the multi-stage injection control in FIG. 2 is shown as being executed by three injections (for example, injection execution signals 205a, 20b, and 205c). However, even when the number of injections is different, the basic control method remains the same.

[0041] Also, as the definition of multi-stage injection in the present invention, it is defined that at least one or more fuel injections are performed during one combustion cycle. Although the position (angle) of this one combustion cycle is different for each cylinder, it is set as 720 deg between the combustion strokes (intake, compression, expansion, exhaust) of a four-cycle internal combustion engine.

[0042] Next, the on-off valve detection unit 102h of the present invention will be further described with reference to FIG. 3. FIG. 3 is a time chart when multi-stage injection control is being executed as in FIG. 2, and shows, in order from the top, a pulse signal 114c to the fuel injection valve 108, a drive current 302, and an on-off valve detection result 303.

[0043] The pulse signal 114c in FIG. 3 is a three-stage injection command, and shows the cases where it becomes ON at time points T304, T310, and T313 and becomes OFF at time points T309, T312, and T315, respectively.

[0044] Based on the command of this pulse signal 114c, a drive current 302 for executing fuel injection is applied to the fuel injection valve 108, and the on-off valve detection result 303 shows the behavior as shown in FIG. 3.

[0045] In FIG. 3, after the driving current 302 reaches the valve opening current 302b at time point T305, the current supply to the fuel injection valve 108 is once stopped until time point T307, and two driving current profiles are described: one that resumes supplying the driving current again from time point T307, and another that uses holding current 1 (current value 302c in FIG. 3) and holding current 2 (current value 302d in FIG. 3). In the present embodiment, the detailed description of (current value 302c in FIG. 3) and holding current 2 (current value 302d in FIG. 3) is omitted.

[0046] At time point T309 when the pulse signal 114c becomes OFF, the driving current 302 stops being supplied to the fuel injection valve 108, and current supply is performed from the next injection start timing (time point T310 or time point T313) in the same driving sequence.

[0047] Next, the description of the on-off valve detection result 303 will be given. In the on-off valve detection unit 102h of the present embodiment, when the pulse signal 114c becomes ON and the driving current 302 reaches the valve opening current 302b (time point T305), it is regarded as valve opening, and the on-off valve detection result 303 is set to ON. This timing is the timing when the valve body of the fuel injection valve 108 (not shown) reaches full lift.

[0048] After that, the driving current 302 performs the above-described valve opening and holding operation until the pulse signal 114c becomes OFF. In the on-off valve detection unit 102h of the present embodiment, this OFF timing (time point T309) is regarded as valve closing, and the on-off valve detection result 303 is set to OFF. As described above, this timing is the timing for performing a predetermined operation so as to quickly remove the residual magnetic force in the fuel injection valve 108 and cause the valve body in the fuel injection valve 108 to close early, and this timing is regarded as valve closing.

[0049] Note that the above-described operations are continued for the specified number of times by multi-stage injection control. Since the behaviors of the driving current 302 and the on-off valve detection result 303 are the same, the description thereof is omitted.

[0050] Next, timing for inputting the information 116 calculated by the on-off valve detection unit 102h of the present invention to the execution injection number determination unit 102g and the execution injection timing determination unit 102f will be described with reference to FIG. 4.

[0051] FIG. 4 shows Pattern 1 and Pattern 2, and for each pattern, it is a time chart showing a pulse signal 114 to the fuel injection valve 108 (pulse signal 114a for Pattern 1 and pulse signal 114b for Pattern 2) and an on-off valve detection result 403 (on-off valve detection result 403a for Pattern 1 and on-off valve detection result 403b for Pattern 2). Also, in FIG. 4, a state where multi-stage injection control is permitted is shown.

[0052] In FIG. 4, the pulse signal 114 is a three-stage injection command, and two patterns are described: Pattern 1 in which all of the injection commands 401a, 401b, and 401c included in the injection command 401 are performed during the intake stroke and compression stroke of the n cylinders, and Pattern 2 in which the injection commands 402a, 402b, and 402c included in the injection command 402 span four processes of the n cylinders.

[0053] First, as also described in FIG. 2, as a general method of so-called angle control for performing architecture driving based on a predetermined crank angle, control reference positions (T408a to T408d) for each cylinder are provided, and the timing of the architecture operation is measured at a desired angle based on these control reference positions (T408a to T408d).

[0054] Based on this, when describing Pattern 1 in FIG. 4, an injection command 401 occurs at an injection timing 410 for multi-stage injection from T408a which is the control reference position of the n cylinders.

[0055] Based on this injection command 401, an on-off valve detection result 403a is output as described with reference to FIG. 3. Since all of this on-off valve detection result 403a occurs during the intake stroke and compression stroke of the n cylinders, similar to the injection command 401, it is input to the actual injection count determination unit 102g and the actual injection timing determination unit 102f at the timing indicated by the control reference position T408c (time point 404a) 360 deg after the control reference position T408a.

[0056] Also, in pattern 2, an injection command 402 occurs at the injection timing 411 for multi-stage injection from T408a, which is the control reference position of the n cylinders.

[0057] Based on this injection command 402, an on-off valve detection result 403b is output as described with reference to FIG. 3. Since all of this on-off valve detection result 403b occurs across the four processes of one combustion cycle of the n cylinders, similar to the injection command 402, it is input to the actual injection count determination unit 102g and the actual injection timing determination unit 102f at the timing indicated by the next control reference position T408a (time point 404b) from the control reference position T408a.

[0058] The concept of the actual injection detection result acquisition timing described above can be applied not only to the control device of this embodiment but also to a system capable of monitoring the actual injection state of multi-stage injection control.

[0059] Next, the drive timing unit conversion unit 102e and the actual injection timing determination unit 102f of this embodiment will be described with reference to FIG. 5.

[0060] Figure 5 is a time chart showing, from above, each signal of the crank, the elapsed time 120 for each fixed angle, the drive timing information 113, the pulse signal 114 to the fuel injection valve 108, the drive timing information 119, the on-off valve detection result 403, and the valve opening timing detection result 502 for both Pattern 1 and Pattern 2. Among them, regarding the drive timing information 113, the commanded injection number 112, the pulse signal 114 to the fuel injection valve 108, and the on-off valve detection result 403, since the content has been explained, the explanation is omitted here. The drive timing information 113 is drive timing angle information, and the drive timing information 119 is drive timing time information.

[0061] In Figure 5, taking Pattern 1 of Figure 4 as an example, an explanation will be given. Also, since only the calculation method of the drive timing information 119 differs between Pattern 1 and Pattern 2 in Figure 5, the calculation of the dynamic timing information 119 will be explained by pattern.

[0062] In the present embodiment, as the execution injection timing determination unit 102f, it is determined whether the difference between the valve opening timing detection result 502 and the drive timing information 119 converges within a predetermined range. It is desirable to set the predetermined range in consideration of the hardware performance of the fuel injection valve control device 101. The information 118 of the determination result is input to the multi-stage injection normal determination unit 102d.

[0063] The valve opening timing detection result 502 is the valve opening timing T502a and T502b (similar to T305, T311, T314 in Figure 3) detected within the region from the control reference position T408a of the nth cylinder to the time point 404a at the time point 404a described in Figure 4.

[0064] The difference between the valve opening timing detection result 502 and the drive timing information 119 is the difference between the two timings for each injection. In the case of Figure 5, the differences in the injection timings for three injections are T502a - T501a and T502b - T501b. This difference does not change the basic calculation method even when the number of times is different.

[0065] The drive timing information 119 uses the elapsed time 120 for each fixed angle and is the result of converting the drive timing information 113 from an angle to time. In Pattern 1, the drive timing information 113 shows the calculation when it is an integer multiple of the elapsed time 120 for each fixed angle. In the example of FIG. 5, since the drive timing information 113 is 7 times the elapsed time 120 for each fixed angle, the T501a showing the result of the drive timing time information 119 is the sum of the seventh elapsed time for each fixed angle from the control reference position T408a of the n cylinders (T501a = t01 + … + t07).

[0066] In Pattern 2, the drive timing information 113 shows the calculation when it is not an integer multiple of the elapsed time 120 for each fixed angle. In the example of FIG. 5, as a result of dividing by a fixed angle, the drive timing information 113 (T602) can be decomposed into an integer multiple (T603) of the elapsed time 120 for each fixed angle and a remainder (T602 - T603). T602 is the sum of the ninth elapsed time for each fixed angle from the control reference position T408a of the n cylinders (T602 = t01 + … + t09). Also, as a method of converting the remainder (T602 - T603) part into time, divide the most recent elapsed time for each fixed angle (t09) by a fixed angle that has been determined, calculate the elapsed time between 1° at t09, and the elapsed time tx of the remainder (T602 - T603) can be calculated by multiplying the elapsed time between 1° and the remainder (T602 - T603). The T501b showing the result of the drive timing information 119 is the sum of the angle-time conversion result T603 of the integer multiple part and the angle-time conversion result tx of the remainder part.

[0067] The setting of the fixed angle varies in concept depending on the control device, but in the present invention, it is set to the minimum elapsed angle of the crank angle signal twice.

[0068] Next, the processing of the drive timing unit conversion unit 102e will be described with reference to FIG. 6. Note that the control flowchart of FIG. 6 shows the processing in one cylinder for convenience of explanation.

[0069] First, in S601, the drive timing unit conversion unit 102e obtains the elapsed time per fixed angle, which is the elapsed time per fixed angle 120 in FIG. 1. In the present embodiment, the elapsed time per fixed angle 120 is the minimum elapsed angle elapsed time of the two crank angle signals described with reference to FIG. 5. Also, regarding the acquisition timing of the elapsed time per fixed angle 120, it is set to be each time the control reference position of the cylinder arrives (in the case of taking FIG. 4 as an example, the acquisition timing of the elapsed time per fixed angle is T408a).

[0070] Next, proceed to S602, and the drive timing unit conversion unit 102e obtains the drive timing information for the multi-stage injection of the cylinder, which is the drive timing information 113 input by the multi-stage injection control calculation unit 102a in FIG. 1. Also, regarding the acquisition timing of the drive timing information 113, it is the same as the acquisition timing in S601.

[0071] Thereafter, proceed to S603, and the drive timing unit conversion unit 102e calculates the division of a fixed angle for calculating the elapsed time per fixed angle defined for unit conversion by the drive timing information 113 acquired in S602.

[0072] Thereafter, proceed to S604, and the drive timing unit conversion unit 102e determines whether there is a remainder in the result of the division. If there is a remainder, proceed to S605 to perform drive timing prediction time processing, and if they do not match, proceed to S606 to perform drive timing measured time processing.

[0073] The drive timing prediction time processing in S605 matches the unit conversion processing content of Pattern 2 shown in FIG. 5, and the drive timing measured time processing in S606 matches the unit conversion processing content of Pattern 1 shown in FIG. 5.

[0074] This determination result information is input to the execution injection timing determination unit 102f in FIG. 1.

[0075] Next, the processing of the execution injection timing determination unit 102f will be described with reference to FIG. 7. Note that the control flowchart of FIG. 7 shows the processing in one combustion cycle of one cylinder for convenience of explanation.

[0076] First, at S701, the execution injection timing determination unit 102f acquires the drive timing information of the multi-stage injection of the cylinder, which is the drive timing information 119 input by the drive timing unit conversion unit 102e in FIG. 1. Also, regarding the acquisition timing of the drive timing information 119, it is set to be each time the control reference position of the cylinder arrives (in the case of FIG. 4 as an example, the information acquisition timing is T408a).

[0077] Next, it proceeds to S702, and the execution injection timing determination unit 102f acquires the actual injection timing detection result. The acquisition timing is the same as the timing of time points 404a or 404b described in FIG. 4. Then, it proceeds to S603, and the execution injection timing determination unit 102f calculates the difference between the actual injection timing and the commanded injection timing for each injection of the cylinder.

[0078] After that, it proceeds to S704, and the execution injection timing determination unit 102f determines whether the timing differences for each injection all converge within a predetermined range. If it is determined that the timing differences are all within the predetermined range, it proceeds to S705, and it is determined that the multi-stage injection control has been executed at the normal timing for the current cylinder. If they do not match, it proceeds to S706, and it is determined that there is an abnormality in the multi-stage injection control for the current cylinder.

[0079] Also, when the execution injection timing determination unit 102f proceeds to S706, it then proceeds to S707 and determines the magnitude relationship between the timing difference and a predetermined value. If the execution injection timing determination unit 102f determines that even one of the plurality (number of injections) of differences exceeds a predetermined value hi, it proceeds to S708 and determines that there is an abnormality that the actual injection of the multi-stage injection is retarded. Also, if the execution injection timing determination unit 102f determines that even one of the plurality (number of injections) of differences is smaller than a predetermined value lo, it proceeds to S709 and determines that there is an abnormality that the actual injection of the multi-stage injection is advanced.

[0080] These determination result information is input to the multi-stage injection normal determination unit 102d in FIG. 1.

[0081] Next, the multi-stage injection control normal abnormality determination method by the multi-stage injection normal determination unit 102d will be described with reference to FIG. 8. Note that the control flowchart in FIG. 8 shows the processing in one combustion cycle of one cylinder for convenience of explanation.

[0082] First, in S801, the multi-stage injection normal determination unit 102d acquires the execution injection number determination result, which is the information 117 of the determination result by the execution injection number determination unit 102g in FIG. 1. Next, in S802, the multi-stage injection normal determination unit 102d determines whether the injection number state determination result of the multi-stage injection control is normal based on the acquired determination result information 117. When the injection number state is normal, the multi-stage injection normal determination unit 102d proceeds to S803 and acquires the execution injection timing determination result. The execution injection timing determination result is the information 118 of the determination result from the execution injection timing determination unit 102f in FIG. 1. When the injection number state is abnormal, the multi-stage injection normal determination unit 102d proceeds to S806 and determines the type of abnormality based on the injection number abnormal state. When the injection number is in an increasing state, the multi-stage injection normal determination unit 102d proceeds to S807 and determines that there is an abnormality in the increase of the multi-stage injection number. When the injection number is in a decreasing state, the multi-stage injection normal determination unit 102d proceeds to S808 and determines that there is an abnormality in the decrease of the multi-stage injection number. Also, after proceeding to S803, the multi-stage injection normal determination unit 102d subsequently proceeds to S804, and determines whether the injection timing state determination result of the multi-stage injection control is normal based on the acquired determination result information 118. If the state of the injection timing is normal, the multi-stage injection normal determination unit 102d proceeds to S805 and determines that the multi-stage injection control is normal. If the injection timing state is abnormal, the multi-stage injection normal determination unit 102d proceeds to S809 and determines the type of timing abnormality based on the injection timing abnormal state. If it is the injection timing advanced state, the multi-stage injection normal determination unit 102d proceeds to S810 and determines that there is a multi-stage injection advance angle abnormality. If it is the injection timing retarded state, the multi-stage injection normal determination unit 102d proceeds to S811 and determines that there is a multi-stage injection retard angle abnormality.

[0083] By the above method, the control device of the present embodiment can monitor the actual injection state of the multi-stage injection control and ensure normal operation. It should be noted that the determination method and comparison method described in this specification are merely examples of the present invention and are not limited to the description method in the specification.

[0084] <Others> Each of the embodiments described above is merely an example, and the present invention is not limited to these contents as long as the features of the invention are not impaired. The present invention is not limited to the above-described embodiments, and combinations thereof and other aspects conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

Explanation of Reference Numerals

[0085] 101... Fuel injection valve control device, 102... Microcomputer

Claims

1. A fuel injection valve control device for controlling a fuel injection valve that injects fuel into an internal combustion engine according to an injection command, comprising an arithmetic processing unit that executes a program related to the control of the fuel injection valve, and a circuit that drives the fuel injection valve in response to the injection command, and wherein the arithmetic processing unit comprises an open / close valve detection unit that detects the open / close state of the fuel injection valve, and a determination unit that determines an abnormality in the drive timing of the fuel injection valve according to the drive timing of the fuel injection valve by the injection command and the open / close state detection signal of the fuel injection valve detected by the open / close valve detection unit, and sets the acquisition timing of the detection result of the open / close valve detection unit to a multiple of the cycle, based on the acquisition timing of the injection command and the cycle of the injection command. A fuel injection valve control device characterized by the above.

2. In the fuel injection valve control device according to Claim 1, the arithmetic processing unit converts the injection command from an angle to time at the acquisition timing of the detection result of the open / close valve detection unit, and compares the injection command and the open / close state detection signal of the fuel injection valve in the same unit. A fuel injection valve control device characterized by the above.

3. In the fuel injection valve control device according to Claim 2, the arithmetic processing unit compares the open / close state detection signal of the fuel injection valve and the injection command converted to time at the acquisition timing of the detection result of the open / close valve detection unit, and determines whether the fuel injection valve is operating at an injection timing corresponding to the injection command. A control device for a fuel injection valve characterized by the above.

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