JP5153688B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine that prohibits ignition when a crankshaft is reversely rotated.

  If the rotation speed of the crankshaft is insufficient, such as during cranking of an internal combustion engine, the crankshaft may reverse from rotation in the normal rotation direction to rotation in the reverse rotation direction. If ignition is performed in such a state, a reverse load may act on the crankshaft or the like to cause damage to the engine body. Therefore, conventionally, the ignition is prohibited when it is determined that the crankshaft is reversely rotated, and the ignition prohibition is canceled when it is determined that the crankshaft has returned from the reverse rotation to the normal rotation after the ignition is prohibited. Control devices for internal combustion engines have been proposed (see, for example, Patent Documents 1 and 2). The reverse rotation determination condition and the normal rotation return determination condition in the technique described in Patent Document 1 are different from those in the technique described in Patent Document 2.

Japanese Patent No. 2780257 Japanese Patent Laying-Open No. 2005-220866

  By the way, in the control device for an internal combustion engine, for example, in order to detect the reverse rotation of the crankshaft with high accuracy, a plurality of reverse rotation determination means having different reverse rotation determination conditions and a plurality of forward rotation return determination conditions different according to the reverse rotation determination conditions. It is conceivable to provide a normal rotation return determination means.

  However, if it is configured to include a plurality of normal rotation return determination means, the timing at which it is determined that the crankshaft has returned to normal rotation differs depending on the determination conditions, so when the driver performs a restart operation after ignition is prohibited, There may be a disadvantage that it takes time to start the internal combustion engine. In other words, the ignition prohibition is not canceled until all of the plurality of normal rotation return determination means determine that the normal rotation is returned, and therefore it may take a long time from the restart operation to the start of the internal combustion engine. There was a risk of decline.

  Accordingly, an object of the present invention is to solve the above-described problems, and to provide a plurality of crankshaft reverse rotation determination means and forward rotation return determination means, and to prohibit ignition when the crankshaft is reversely rotated and to appropriately cancel the ignition prohibition. An object of the present invention is to provide a control device for an internal combustion engine that is executed at timing to improve restartability.

In order to achieve the above object, according to claim 1, a plurality of reverse rotation determination means for determining, based on different reverse rotation determination conditions, that the crankshaft of the internal combustion engine has reversed from the rotation in the forward rotation direction, When the crankshaft is determined to be reverse rotation in at least one of a plurality of reverse rotation determination means, an ignition prohibition means for prohibiting ignition of the internal combustion engine, and after ignition of the internal combustion engine is prohibited by the ignition prohibition means, e Bei a plurality of forward return determination means for determining based on different forward recovery determination condition that the crankshaft is returned from the reverse rotation to the normal rotation, the at least one of the plurality of forward recovery determination means If the crankshaft is determined to have returned from the reverse rotation to the normal rotation, a control apparatus for an internal combustion engine prohibited Ru is released ignition of the internal combustion engine, further, at said crankshaft Crank angle signal output means for outputting a crank angle signal for each crank angle, an AC generator driven by rotation of the crankshaft to output an AC voltage, and when the crank angle signal is output, the AC generator Polarity determination means for determining the polarity of the AC voltage output from the at least one of the plurality of reverse rotation determination means when the determined cycle of the polarity and the crankshaft are rotated in the forward rotation direction. When the forward rotation polarity period to be output from the AC generator does not coincide with the crankshaft, the crankshaft is determined to be reverse rotation, and at least one of the plurality of normal rotation return determination means is determined by the ignition prohibition means. After the ignition of the internal combustion engine is prohibited, when the determined polarity cycle coincides with the forward rotation polarity cycle, the crankshaft is rotated from reverse to forward rotation. Determined has been restored and was constructed to release the prohibition of the ignition of the internal combustion engine.

In the control device for an internal combustion engine according to claim 2 , a plurality of circumferentially arranged lengths of the rotor rotating in conjunction with the crankshaft are arranged at equal angular intervals. A projection, a projection position signal output means for outputting a front end position signal and a rear end position signal indicating a front end position and a rear end position of the projection, disposed at a stationary position opposite to the projection; and a front end position signal is output. Time to measure the elapsed time from when the rear end position signal is output to when the rear end position signal is output until the front end position signal of the next protrusion is output. Measurement means, and at least one of the plurality of reverse rotation determination means determines that the crankshaft is reverse rotation based on the measured protrusion elapsed time and the protrusion-to-protrusion elapsed time, and the plurality of forward rotation return determinations At least of means It is determined that the crankshaft has returned from reverse rotation to normal rotation based on the measured protrusion elapsed time and the protrusion-to-protrusion elapsed time after ignition of the internal combustion engine is prohibited by the ignition prohibiting means. Configured.

In the control device for an internal combustion engine according to claim 3 , the time measuring means measures the protrusion elapsed time and the protrusion elapsed time each time the front end position signal and the rear end position signal of the protrusion are output. At the same time, the reverse rotation determination means is measured when the ratio of the inter-projection elapsed time measured this time and the previously measured inter-projection elapsed time is equal to or more than a first predetermined value, or when the projection elapsed time measured this time is measured last time. When the ratio of the protrusion elapsed time is equal to or greater than the second predetermined value, the crankshaft is determined to be reverse.

In the control apparatus for an internal combustion engine according to claim 4 , any one of the plurality of protrusions includes a forward rotation determination protrusion formed so that the circumferential length is different from that of the remaining protrusion. The time measuring means measures the protrusion elapsed time and the protrusion elapsed time each time the front end position signal and the rear end position signal of the protrusion are output, and the normal rotation return determination means is measured this time. And calculating the amount of change between the ratio of the elapsed time between the protrusions and the elapsed time between the protrusions and the ratio of the elapsed time between the protrusions and the elapsed time between the protrusions measured last time, and based on the calculated amount of change, the protrusion for forward rotation determination. Is detected, it is determined that the crankshaft has returned from reverse rotation to normal rotation.

6. The control apparatus for an internal combustion engine according to claim 5 , wherein when at least one of the plurality of reverse rotation determination means determines that the crankshaft is reverse rotation, the fuel injection prohibition means prohibits fuel injection of the internal combustion engine. And the fuel injection prohibiting means prohibits fuel injection of the internal combustion engine when at least one of the plurality of normal rotation return determination means determines that the crankshaft has returned from reverse rotation to normal rotation. It was configured to cancel.

  The control apparatus for an internal combustion engine according to claim 1 is configured to prohibit ignition of the internal combustion engine when the crankshaft is determined to be reverse rotation in at least one of a plurality of reverse rotation determination means having different reverse rotation determination conditions. Therefore, the reverse rotation of the crankshaft can be accurately detected and ignition can be prohibited, so that the reverse load does not act on the crankshaft and the like, and damage to the internal combustion engine body can be prevented.

  In addition, after the ignition of the internal combustion engine is prohibited, when it is determined that the crankshaft has returned from the reverse rotation to the normal rotation in at least one of a plurality of normal rotation return determination means having different normal rotation return determination conditions, Since the prohibition of ignition is canceled, that is, when the crankshaft is determined to return to normal rotation in at least one of the plurality of normal rotation return determination means, the ignition prohibition is canceled. Therefore, it is possible to cancel the ignition prohibition at an appropriate timing at an early stage, thereby improving the restartability.

In addition , when the crank angle signal is output, the polarity of the AC voltage output from the AC generator is determined, and when the determined polarity cycle does not match the polarity cycle during forward rotation, the crankshaft is determined to be reverse. In addition , after the ignition of the internal combustion engine is prohibited, when the determined polarity cycle coincides with the forward polarity polarity cycle, it is determined that the crankshaft has returned from the reverse rotation to the normal rotation, and the internal combustion engine ignition is prohibited. since it is configured to so that to release the, in addition to the effects mentioned above, we are possible to detect that the crankshaft has returned to normal rotation since and reverse reversed more accurately.

The control apparatus for an internal combustion engine according to claim 2 includes a plurality of protrusions arranged on a circumference of the rotor, and includes a front end position signal and a rear end position signal indicating a front end position and a rear end position of the protrusion. Based on the measured protrusion elapsed time and the elapsed protrusion elapsed time, it is configured to determine whether the crankshaft is reverse and normal rotation return. In addition to the effects described above, the crankshaft reversely rotates and returns from reverse rotation to normal rotation. This can be detected more accurately.

In the control apparatus for an internal combustion engine according to claim 3, when the ratio of the elapsed time between projections measured this time and the elapsed time between projections measured last time is equal to or more than a first predetermined value, or the projection measured this time When the ratio of the elapsed time and the previously measured protrusion elapsed time is equal to or greater than the second predetermined value, the crankshaft is determined to be reverse rotation. Therefore, in addition to the effect described in claim 3, the crankshaft is reversely rotated. This can be detected even more accurately.

In the control apparatus for an internal combustion engine according to claim 4 , the amount of change between the ratio of the protrusion elapsed time and the protrusion elapsed time measured this time and the ratio of the protrusion elapsed time and the protrusion elapsed time measured last time is changed. Accordingly, when a forward rotation judging projection having a circumferential length different from that of the remaining projection is detected, it is judged that the crankshaft has returned to the normal rotation. Therefore, the effect described in claim 3 or 4 In addition, it is possible to more accurately detect that the crankshaft has returned from the reverse rotation to the normal rotation, and the ignition prohibition can be canceled at a more appropriate timing.

In the control device for an internal combustion engine according to claim 5 , the fuel injection of the internal combustion engine is prohibited when the crankshaft is determined to be reverse rotation in at least one of the plurality of reverse rotation determination means. In addition to the above effect, the load due to reverse rotation does not act on the crankshaft and the like, and damage to the internal combustion engine body can be prevented more reliably.

  In addition, when at least one of the plurality of normal rotation return determination means determines that the crankshaft has returned from the reverse rotation to the normal rotation, the configuration prohibits the prohibition of fuel injection of the internal combustion engine, that is, the plurality of normal rotation rotations. Since it is configured to cancel the prohibition of fuel injection when the crankshaft is determined to return to normal rotation in at least any one of the return determination means, the cancellation of the fuel injection prohibition is executed at an appropriate timing early. Therefore, restartability can be further improved.

1 is a schematic diagram showing an overall control apparatus for an internal combustion engine according to an embodiment of the present invention. It is explanatory drawing of the rotor etc. which comprise the generator shown in FIG. FIG. 2 is a block diagram showing the overall configuration of an ECU shown in FIG. 1. 2 is a flowchart showing the operation of the control device for the internal combustion engine shown in FIG. 1. FIG. 5 is a sub-routine flowchart of the crank angle reference position detection process of FIG. 4. 6 is a time chart for explaining detection of a crank angle reference position in FIG. 5. FIG. 7 is a time chart for explaining the detection of the crank angle reference position, as in FIG. 6. FIG. 5 is a sub-routine flowchart of the first reverse rotation / forward rotation return determination process of FIG. 4. FIG. FIG. 9 is a time chart for explaining a first reverse rotation / forward rotation return determination process of FIG. 8. FIG. FIG. 5 is a sub-routine flowchart of the second reverse rotation / forward rotation return determination process of FIG. 4. FIG. It is a time chart for demonstrating the 2nd reverse rotation / forward rotation determination process of FIG. FIG. 5 is a sub-routine flowchart showing the reverse rotation / forward rotation determination determination process of FIG. 4. FIG. 5 is a sub-routine flowchart of the ignition output process of FIG. FIG. 5 is a sub-routine flowchart of the fuel injection process of FIG. 4. 5 is a flowchart showing the operation of the control device for the internal combustion engine executed in parallel with the flowchart of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment for carrying out an internal combustion engine control apparatus according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing an overall control apparatus for an internal combustion engine according to an embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes an internal combustion engine (hereinafter referred to as “engine”) mounted on a vehicle (not shown) (for example, a motorcycle). The engine 10 is a four-cycle single-cylinder water-cooled type and is composed of a gasoline engine having a displacement of about 250 cc. Reference numeral 10a denotes a crankcase of the engine 10.

  A throttle valve 14 is disposed in the intake pipe 12 of the engine 10. The throttle valve 14 is mechanically connected via a throttle wire (both not shown) to an accelerator (throttle grip) provided on the vehicle handlebar so as to be manually operated by the driver, depending on the operation amount of the accelerator. The amount of air that is opened and closed and drawn into the engine 10 from the air cleaner 16 through the intake pipe 12 is adjusted.

  In the intake pipe 12, an injector 20 is disposed near the intake port on the downstream side of the throttle valve 14, and gasoline fuel is injected into the intake air adjusted by the throttle valve 14. The injected fuel is mixed with intake air to form an air-fuel mixture, and the air-fuel mixture flows into the combustion chamber 24 when the intake valve 22 is opened.

  The air-fuel mixture flowing into the combustion chamber 24 is ignited and burned when the spark plug 30 is spark-discharged by the high voltage supplied from the ignition coil 26, and the piston 32 is driven downward in FIG. Rotate. The exhaust gas generated by the combustion flows through the exhaust pipe 40 when the exhaust valve 36 is opened. A catalyst device 42 is disposed in the exhaust pipe 40 to remove harmful components in the exhaust gas. The exhaust gas purified by the catalyst device 42 flows further downstream and is discharged to the outside of the engine 10.

  A throttle opening sensor 44 composed of a potentiometer is provided in the vicinity of the throttle valve 14 to generate an output indicating the opening θTH of the throttle valve 14. An intake air temperature sensor 46 is provided on the upstream side of the throttle valve 14 of the intake pipe 12 to generate an output indicating the temperature TA of the intake air, and an absolute pressure sensor 50 is provided on the downstream side to provide the absolute pressure in the intake pipe (engine Load) produces an output indicating PBA.

  A water temperature sensor 52 is attached to the cooling water passage 10b of the cylinder block of the engine 10, and generates an output corresponding to the temperature (engine cooling water temperature) TW of the engine 10. A crank angle sensor (crank angle signal output means; projection position signal output means) 54 made up of an electromagnetic pickup is disposed near the crankshaft 34 of the engine 10 and on the wall surface (static position) of the crankcase 10a. The crank angle sensor 54 will be described in detail later.

  An AC generator (hereinafter simply referred to as “generator”) 60 is connected to the crankshaft 34 of the engine 10. The generator 60 includes a rotor (timing rotor) 60a connected to the crankshaft 34, a permanent magnet 60b attached to the rotor 60a, and three-phase stator coils 60c, 60d disposed at positions facing the permanent magnet 60b. 60e and reverse detection coil 60f.

  FIG. 2 is an explanatory diagram of the rotor 60a and the like constituting the generator 60 shown in FIG.

  As shown in FIG. 2, the rotor 60 a has a cylindrical shape and rotates in conjunction with (synchronizes with) the crankshaft 34. The rotor 60a also serves as the flywheel of the engine 10. A plurality (18) of protrusions 60g, which are made of a magnetic material and have a predetermined circumferential length, are arranged on the circumference (outer peripheral side) of the rotor 60a at equal angular intervals with a predetermined distance. Specifically, the 18 protrusions 60g are arranged such that the rear end positions of the protrusions 60g in the rotational direction of the rotor 60a are equally spaced at predetermined crank angles (more specifically, 20 °) of the crankshaft 34. Placed in.

  One of the plurality of protrusions 60g is a reference protrusion (indicated by reference numeral 60g1 in FIG. 2) for detecting a crank angle reference position. The reference protrusion 60g1 is formed such that the circumferential length from the front end position to the rear end position is different from that of the remaining (other) protrusion 60g2, specifically, longer than that of the protrusion 60g2. At the same time, the rear end position is set to be 10 ° before top dead center (BTDC 10 ° (crank angle reference position)). The reference protrusion 60g1 also functions as a forward rotation determination protrusion for determining that the crankshaft 34 has returned from the reverse rotation to the normal rotation, which will be described later.

  The crank angle sensor 54 described above is disposed at a stationary position facing the protrusion 60g of the rotor 60a. Therefore, the crank angle sensor 54 outputs a pulse signal each time the protrusion 60g passes in the vicinity as the rotor 60a rotates. Specifically, the crank angle sensor 54 outputs a pulse signal (front end position signal) having a negative polarity when the front end position of each projection 60g passes in the rotation direction and the rear end position passes. A pulse signal having a positive polarity (rear end position signal) is output. That is, the crank angle sensor 54 outputs a pulse signal (crank angle signal) having a negative polarity or a positive polarity at every predetermined crank angle (20 °) of the crankshaft 34. Since the circumferential length of the reference protrusion 60g1 is longer than that of the remaining protrusion 60g2, the timing for detecting the front end position of the reference protrusion 60g1 by the crank angle sensor 54 is earlier than that of the remaining protrusion 60g2.

  The permanent magnet 60b is attached to the inner peripheral side of the rotor 60a, and the S pole and the N pole are alternately arranged at equal angles (specifically, every 30 °), in other words, the S pole and the N pole. Are arranged every 60 ° as one set (one pair). Further, the reverse rotation detection coil 60f is arranged to be at the crank angle reference position (BTDC 10 °).

  Thus, when the rotor 60a (specifically, the permanent magnet 60b attached to the rotor 60a) is rotated with the rotation of the crankshaft 34, the generator 60 rotates the stator coils 60c, 60d, 60e and reversely by electromagnetic induction. An AC voltage is output from the detection coil 60f. Specifically, the stator coils 60c, 60d, and 60e output a three-phase AC voltage composed of U, V, and W phases, and the reverse rotation detection coil 60f outputs a one-phase AC voltage.

  Thus, the generator 60 is composed of a permanent magnet type AC generator and is driven by the rotation of the crankshaft 34 to output an AC voltage. The AC voltage output from the above-described reverse rotation detection coil 60f is an AC voltage that takes one period of time required for the rotor 60a (crankshaft 34) to rotate 60 °.

  Returning to the description of FIG. 1, the three-phase AC voltage output from the stator coils 60 c, 60 d and 60 e of the generator 60 is input to the battery 64 via the regulating rectifier 62.

  The regulate rectifier 62 includes a rectifier circuit 62a and an output voltage adjustment circuit 62b. The rectifier circuit 62a rectifies the three-phase AC voltage input from the stator coils 60c, 60d, and 60e into a DC voltage by a bridge circuit (not shown) and outputs the DC voltage to the output voltage adjustment circuit 62b. The output voltage adjusting circuit 62b adjusts the input DC voltage to generate a power supply voltage, supplies the power supply voltage to the battery 64 and charges it, and at the same time, an electronic control unit (hereinafter referred to as “ECU”). ) 70 is also supplied as an operating power source. The battery 64 supplies operating power to the ECU 70 when no AC voltage is output from the generator 60, for example, when the engine is started.

  The output of each sensor such as the crank angle sensor 54 described above and the AC voltage output from the reverse rotation detection coil 60 f of the generator 60 are input to the ECU 70.

  FIG. 3 is a block diagram showing the overall configuration of the ECU 70.

  The ECU 70 comprises a microcomputer, and as shown in FIG. 3, a waveform shaping circuit 70a, a rotation speed counter 70b, a reference voltage source 70c, a comparator circuit 70d, an A / D conversion circuit 70e, a CPU 70f, and an ignition circuit 70g, a drive circuit 70h, a ROM 70i, a RAM 70j, and a timer 70k.

  The waveform shaping circuit 70a shapes the output (pulse signal, signal waveform) of the crank angle sensor 54 into a rectangular pulse signal and outputs it to the rotation number counter 70b. The rotational speed counter 70b counts the input pulse signal to detect (calculate) the engine rotational speed NE, and outputs a signal indicating the engine rotational speed NE to the CPU 70f. The reference voltage source 70c outputs the negative DC voltage as a reference voltage to the non-inverting input terminal of the comparator circuit 70d.

  The comparator circuit 70d is composed of an operational amplifier, and the AC voltage of the reverse rotation detection coil 60f is input to the inverting input terminal. The comparator circuit 70d compares the AC voltage with the reference voltage. When the AC voltage is larger than the reference voltage (in other words, when the polarity of the AC voltage is positive), the comparator circuit 70d outputs a high-level comparison result signal. When it is smaller (when the polarity of the AC voltage is negative), a low level comparison result signal is output to the CPU 70f. The A / D conversion circuit 70e receives the output of each sensor such as the throttle opening sensor 44 and the intake air temperature sensor 46, converts the analog signal value into a digital signal value, and outputs it to the CPU 70f.

  The CPU 70f performs an operation according to a program stored in the ROM 70i based on the converted digital signal, the comparison result signal from the comparator circuit 70d, and the like, and the ignition control signal of the ignition coil 26 when the crank angle is the ignition output timing. Is output to the ignition circuit 70g (that is, ignition timing control is performed). Further, the CPU 70f similarly performs a calculation according to a program stored in the ROM 70i based on each signal, and sends a fuel injection control signal to the drive circuit 70h at the fuel injection timing (performs fuel injection control).

  The ignition circuit 70g performs ignition by energizing the ignition coil 26 in accordance with an ignition control signal from the CPU 70f. The drive circuit 70h drives the injector 20 to inject fuel in response to a fuel injection control signal from the CPU 70f. In the RAM 70j, for example, data such as the ignition timing and the fuel injection amount calculated in the ignition timing control and the fuel injection control are written. The timer 70k is used for time measurement processing performed in a program described later.

  FIG. 4 is a flowchart showing the operation of the control apparatus for an internal combustion engine according to this embodiment. The illustrated program is executed (looped) every time a crank angle signal corresponding to either the front end position or the rear end position of the protrusion 60g of the rotor 60a is input in the ECU 70.

  First, in S10, processing for detecting a crank angle reference position is performed. FIG. 5 is a sub-routine flowchart of the crank angle reference position detection process of S10, and FIG. 6 is a time chart for explaining the detection of the crank angle reference position.

  Prior to the description of the flowchart of FIG. 5, detection of the crank angle reference position will be described with reference to FIG. In FIG. 6, the shape of the outer periphery of the rotor 60a, the output signal of the crank angle sensor 54, the output signal of the waveform shaping circuit 70a, etc. are shown in order from the top.

  The crank angle reference position is detected by determining whether or not the reference protrusion 60g1 of the rotor 60a is detected based on the output of the crank angle sensor 54. That is, as shown in FIG. 6, the crank angle sensor 54 passed the front end position signal (specifically, a negative pulse signal) when the front end position of the protrusion 60g of the rotor 60a passed, and the rear end position passed. Sometimes a rear end position signal (positive pulse signal) is output. The waveform shaping circuit 70a outputs a pulse signal that is high when the signal input from the crank angle sensor 54 is a front end position signal that is equal to or lower than the predetermined voltage −Vth, and that is low when the rear end position signal is equal to or higher than the predetermined voltage Vth. Output.

  Accordingly, the time during which the high-level pulse signal is output in the waveform shaping circuit 70a is the time from when the crank end sensor 54 outputs the front end position signal to when the rear end position signal is output, in other words, the protrusion 60g. Is equivalent to the time required to pass. On the other hand, the time when the low level pulse signal is output is the time from when the rear end position signal is output until the front end position signal of the next protrusion 60g is output, that is, between the two adjacent protrusions 60g. This corresponds to the time required for passing the part. In the following, the time for the projection 60g to pass is referred to as “projection elapsed time”, and the time for the portion between the two adjacent projections 60g to pass is referred to as “inter-projection elapsed time”.

  In the reference protrusion 60g1, as described above, the detection timing of the front end position by the crank angle sensor 54 is earlier than the remaining protrusion 60g2, so the protrusion elapsed time and the inter-projection elapsed time of the reference protrusion 60g1 are the same as those of the other protrusions 60g2. It will be different.

  From the above, in the control apparatus for an internal combustion engine according to this embodiment, the above-described protrusion elapsed time and the protrusion-to-protrusion elapsed time are measured, and whether or not the reference protrusion 60g1 is detected based on each measured time ( It is determined whether or not the crankshaft 34 is at the crank angle reference position when the reference protrusion 60g1 is detected.

  This will be described in detail with reference to the flowchart of FIG. 5. First, in S100, it is determined whether or not the front end position signal is output from the crank angle sensor 54. Specifically, the rising edge is detected in the waveform shaping circuit 70a. It is judged whether it was done. When the result is affirmative in S100, the process proceeds to S102, the measurement of the elapsed time between protrusions (described later) by the timer 70k is terminated, and the process proceeds to S104, where the previously set elapsed time TCDENT between the protrusions is set to the previous projected time TCDENT1. At the same time, the inter-projection elapsed time obtained in S102 is set to the inter-projection elapsed time TCDENT as the value measured this time, that is, the inter-projection elapsed time TCDENT and the previous inter-projection elapsed time TCDENT1 are updated.

  Next, the process proceeds to S106, and measurement of the protrusion elapsed time is started. After the process of S106 or when the result in S100 is negative, the process proceeds to S108, and whether or not a rear end position signal is output from the crank angle sensor 54 (specifically, whether or not a falling edge is detected in the waveform shaping circuit 70a). Judge). When the result in S108 is negative, the subsequent processing is skipped. When the result is affirmative, the process proceeds to S110, and the measurement of the protrusion elapsed time started in S106 is ended.

  Next, the process proceeds to S112, and the previously set protrusion elapsed time TCPRJ is set to the previous protrusion elapsed time TCPRJ1, and the protrusion elapsed time obtained in S110 is set to the protrusion elapsed time TCPRJ as the currently measured value, that is, the protrusion elapsed time. The time TCPRJ and the last protrusion elapsed time TCPRJ1 are updated. Then, the process proceeds to S114 to start measuring the elapsed time between protrusions.

  As described above, in the processing from S100 to S114, the protrusion elapsed time TCPRJ from when the front end position signal is output from the crank angle sensor 54 to when the rear end position signal is output is measured and the rear end position signal is output. This is a process of measuring the inter-projection elapsed time TCDENT until the front end position signal of the next projection 60g is output. The protrusion elapsed time TCPRJ and the protrusion-to-protrusion elapsed time TCENT are measured each time the front end position signal and the rear end position signal of the protrusion 60g are output as described above.

  Next, in S116, the value of the crank stage CALSTG is incremented by one. The crank stage CALSTG is a stage number obtained by dividing one rotation of the crankshaft (360 CA) at equal intervals by a projection 60 g. For example, 18 cranks up to 17 with 10 ° (ATDC 10 °) after top dead center as 0 It is a number indicating the angular position and is used for ignition timing control, fuel injection control, and the like.

Next, in S118, the first ratio RTCPD indicating the ratio between the projection elapsed time TCPRJ and the projection elapsed time TCDENT calculated last time is set as the previous value in the first ratio RTCPD1. In S120, the ratio of the protrusion elapsed time TCPRJ and the protrusion-to-projection elapsed time TCDENT obtained in S104 and S112 is calculated, and the calculated value is set as the current value in the first ratio RTCPD. Specifically, the current first ratio RTCPD is calculated according to the following equation (1).
RTCPD = TCPRJ / TCDENT (1)

  Next, in S122, it is determined whether or not the bit of the reference protrusion detection flag F_LONG indicating that the reference protrusion 60g1 has been detected is “1”. Since the initial value of the flag F_LONG is set to 0, when the process of S122 is executed for the first time, it is denied and the process proceeds to S124, and the amount of change between the first ratio RTCPD and the previous first ratio RTCPD1 is calculated (more precisely, Then, the first ratio RTCPD1 is subtracted from the previous first ratio RTCPD to calculate a difference), and it is determined whether or not the calculated change amount is equal to or greater than the first determination threshold A.

  The process of S124 will be described with reference to FIG. Since the reference protrusion 60g1 has a longer circumferential length than the other protrusions 60g2, the protrusion elapsed time TCPRJ is calculated as the inter-projection elapsed time at the time t11 when the rear end position of the reference protrusion 60g1 passes. The first ratio RTCPD obtained by dividing by TCDENT is larger than the previous first ratio RTCPD1.

  Therefore, in S124, the amount of change between the first ratio RTCPD and the previous first ratio RTCPD1 is calculated, and when the calculated amount of change is equal to or greater than the first determination threshold A, it is determined that the reference protrusion 60g1 has passed. I did it. For this reason, the first determination threshold A is appropriately set to a value that can be determined that the reference protrusion 60g1 has passed in consideration of the circumferential length of the reference protrusion 60g1 and the like.

  When the result in S124 is affirmative, the process proceeds to S126, where the bit of the reference protrusion detection flag F_LONG is set to 1, while when the result is negative (when it is not determined that the reference protrusion 60g1 has passed), the process proceeds to S128 and the bit of the flag F_LONG Is set to 0.

  When the bit of the flag F_LONG is set to 1, it is affirmed in S122 in the subsequent program loop and proceeds to S130, and the amount of change between the previous first ratio RTCPD1 and the first ratio RTCPD (more precisely, the first first time Is calculated by subtracting the first ratio RTCPD from the ratio RTCPD1 to determine whether the calculated change amount is equal to or greater than the second determination threshold value B.

  This process will be described in detail. As can be seen from FIG. 6, at the time t12 when the rear end position of the next protrusion 60g2 passes after passing through the reference protrusion 60g1, the protrusion elapsed time TCPRJ indicated by the imaginary line is calculated as the inter-projection elapsed time TCDENT. The first ratio RTCPD obtained by dividing by is smaller than the previous first ratio RTCPD1.

  Therefore, in S130, when the amount of change calculated by subtracting the first ratio RTCPD from the first ratio RTCPD1 is equal to or greater than the second determination threshold value B, the next protrusion 60g2 passes after the reference protrusion 60g1. Judgment was made. The second determination threshold value B is appropriately set to such a value that it can be determined that the next protrusion 60g2 has passed in consideration of the circumferential lengths of the reference protrusion 60g1 and the protrusion 60g2.

  When the result in S130 is negative, the program proceeds to S132, in which the bit of the reference position detection flag F_TCTDC is set to 0. On the other hand, when the result in S130 is affirmative (that is, it is determined that the reference protrusion 60g1 and the next protrusion 60g2 have passed through in this order), it is determined that the crank angle reference position (BTDC 10 °) has been detected, and the process proceeds to S134. The bit of the protrusion detection flag F_LONG is set to 0, the process proceeds to S136, and the bit of the reference position detection flag F_TCTDC is set to 1.

  That is, setting the bit of the flag F_TCTDC to 1 means that the crank angle reference position has been detected reliably, and setting it to 0 means that the crank angle reference position has not been detected. After the process of S136, the process proceeds to S138, and the value of the crank stage CALSTG is reset to zero.

  Here, the crank angle reference position detection process when the crankshaft 34 rotates in the reverse direction will be described.

  FIG. 7 is a time chart similar to FIG. 6 for explaining the detection of the crank angle reference position when the crankshaft 34 is reversed.

  As shown in FIG. 7, at the time t21 when the reference projection 60g1 passes while the crankshaft 34 is reversed, the amount of change obtained by subtracting the first ratio RTCPD1 from the previous time is the first ratio RTCPD. It becomes smaller than that during forward rotation, in other words, less than the first determination threshold A. Similarly, even at time t22 when the next protrusion 60g2 passes after the reference protrusion 60g1, the amount of change obtained by subtracting the first ratio RTCPD from the previous first ratio RTCPD1, as indicated by the imaginary line, is It is smaller than that during forward rotation and is less than the second determination threshold B.

  Therefore, when the crankshaft 34 is rotating in the reverse direction, the determination in S124 and S130 is negative, the crank angle reference position is not detected, and the bit of the reference position detection flag F_TCTDC never becomes 1. Therefore, as will be described later, when the bit of the flag F_TCTDC is changed from 0 to 1 and the crank angle reference position can be detected after the crankshaft 34 is determined to be reverse rotation, the crankshaft 34 is changed from reverse rotation to forward rotation. It is possible to determine that it has returned.

  Thus, the ratio of the protrusion elapsed time TCPRJ and the protrusion-to-projection elapsed time TCDENT measured this time (first ratio RTCPD) and the ratio of the protrusion elapsed time TCPRJ1 and the protrusion-to-projection elapsed time TCDENT1 measured last time (first previous time When the reference protrusion 60g1 is detected based on the calculated change amount with the ratio RTCPD1), it can be determined that the crankshaft 34 has returned from the reverse rotation to the normal rotation. As can be seen from this, the reference protrusion 60g1 also functions as a forward rotation determination protrusion for determining that the crankshaft 34 has returned to the normal rotation.

  Returning to the description of FIG. 4, the process then proceeds to S <b> 12, in which it is determined whether a rear end position signal is output from the crank angle sensor 54. When the result in S12 is negative, the subsequent processing is skipped, while when the result is affirmative, the process proceeds to S14, and the first reverse rotation / normal rotation is determined based on the protrusion elapsed time TCPRJ or the like to determine the reverse rotation and the normal rotation return. Performs a return / return determination process.

  FIG. 8 is a sub-routine flow chart of the first reverse rotation / normal rotation return determination process in S14, and FIG. 9 is a time chart for explaining the first reverse rotation / normal rotation return determination process.

As shown in FIG. 8, first, in S200, it is determined whether or not the bit of the first reverse rotation determination flag F_REVCRK (described later) is 1. Since the initial value of the flag F_REVCRK is set to 0, when the process of S200 is executed for the first time, it is usually denied and the process proceeds to S202, and the ratio between the inter-projection elapsed time TCDENT and the previous inter-projection elapsed time TCDENT1 (second ratio RTCDENT). ) And a ratio between the protrusion elapsed time TCPRJ and the previous protrusion elapsed time TCPRJ1 (third ratio RTCPRJ). Specifically, the second and third ratios RTCDENT and RTCPRJ are calculated according to the following equations (2) and (3).
RTCDENT = TCDENT / TCDENT1 (2)
RTCPRJ = TCPRJ / TCPRJ1 Formula (3)

  Next, in S204, it is determined whether the second ratio RTCDENT is equal to or greater than a first predetermined value. When the result in S204 is negative, the program proceeds to S206, in which it is determined whether the third ratio RTCPRJ is equal to or greater than a second predetermined value. The processing from S202 to S206 is processing for determining whether or not the crankshaft 34 is reversely rotated.

  More specifically, referring to FIG. 9, when the crankshaft 34 reverses from rotation in the normal rotation direction to rotation in the reverse rotation direction, the rotation speed in the normal rotation direction gradually decreases and temporarily stops. Then, the speed in the reverse direction is generated. Therefore, at the time point t31 when the crankshaft 34 is reversely rotated, the current value of the protrusion elapsed time TCPRJ or the inter-projection elapsed time TCDENT becomes larger than the previous value due to the deceleration / stop of the crankshaft 34.

  Therefore, in the processing from S202 to S206, the ratio between the current value and the previous value (second and third ratios RTCDENT, RTCPRJ) in the inter-projection elapsed time TCDENT and the protrusion elapsed time TCPRJ is calculated and calculated. When the second ratio RTCDENT is equal to or greater than the first predetermined value or the third ratio RTCPRJ is equal to or greater than the second predetermined value, it is determined that the crankshaft 34 is reversed. Therefore, both the first and second predetermined values are appropriately set to values that can determine that the crankshaft 34 is reversely rotated. In addition, at the time t31 in FIG. 9, the case where the third ratio RTCPRJ is equal to or greater than the second predetermined value is shown.

  If the description of FIG. 8 is continued, when the result in S206 is negative, the process proceeds to S208, and the bit of the first reverse rotation determination flag F_REVCRK is set to 0, while when the result is positive in S204 or S206, the process proceeds to S210, and the flag F_REVCRK Set the bit of. That is, setting the bit of the flag F_REVCRK to 1 means that the crankshaft 34 is determined to be reverse based on the measured protrusion elapsed time TCPRJ and the protrusion elapsed time TCDENT. This means that the crankshaft 34 is determined to be forward rotation.

  When it is determined that the crankshaft 34 is reverse and the bit of the flag F_REVCRK is set to 1, in the next and subsequent program loops, an affirmative determination is made in S200 and the process proceeds to S212 to determine whether or not the bit of the reference position detection flag F_TCTDC is 1 . As described above, after the crankshaft 34 is determined to be reverse rotation, when the bit of the flag F_TCTDC becomes 0 to 1 and the crank angle reference position can be detected, it is determined that the crankshaft 34 has returned from reverse rotation to normal rotation. Therefore, when the result in S212 is affirmative, the process proceeds to S208, and the bit of the first reverse rotation determination flag F_REVCRK is set to 0 (time point t32). If the determination at S212 is No, S208 is skipped.

  Returning to FIG. 4, the process then proceeds to S <b> 16, where a second reverse rotation / normal rotation return determination process is performed to determine reverse rotation and normal rotation return of the crankshaft 34 based on the AC voltage output from the AC generator 60.

  FIG. 10 is a sub-routine flowchart of the second reverse rotation / forward rotation determination process.

  Prior to the description of this figure, the reverse rotation determination in the second reverse rotation / forward rotation determination process will be described with reference to the time chart of FIG.

  In FIG. 11, the actual rotation direction of the crankshaft 34, the output signal of the waveform shaping circuit 70a and the crank angle sensor 54, the AC voltage output from the reverse rotation detection coil 60f of the generator 60, and the AC voltage in that order from the top. A polarity detection state, a normal rotation period counter CTFORWARD, which will be described later, and a second reverse rotation determination flag F_REVACG are shown.

  Explaining from the time point t41 to t46 when the crankshaft 34 rotates in the forward rotation direction as an example, the interval of the trailing edge (rear end position signal) of each pulse signal output from the waveform shaping circuit 70a is shown in the figure. Thus, this corresponds to the time required for the crankshaft 34 to rotate 20 ° (20 CA).

  The reverse rotation detection coil 60f of the generator 60 outputs an alternating voltage having a period of one period required for the rotor 60a (crankshaft 34) to rotate 60 °. When the crank angle signal is output from the crank angle sensor 54, the polarity of the AC voltage is precisely when each pulse signal of the waveform shaping circuit 70a becomes a falling edge (the rear end position signal is output). When detected (determined) based on the comparison result signal of the comparator circuit 70d, it can be seen that a positive polarity is obtained at time t41, a positive polarity at time t42, and a negative polarity at time t43, as shown.

  In FIG. 11, when the crankshaft 34 reverses at time t46 but does not reverse at time t46 (when rotation in the normal rotation direction is continued), the polarity of the generator 60 is indicated by an imaginary line. Similarly, during the subsequent time points t44 to t46, the positive electrode is obtained at the time point t44, the positive electrode is obtained at the time point t45, and the negative electrode is obtained at the time point t46 (specifically, the ignition output timing).

  That is, at the time when the crank angle signal is output, the polarity cycle of the AC voltage to be output from the AC generator 60 when the crankshaft 34 is rotated in the forward rotation direction is “positive electrode”, “positive electrode”, “negative electrode”. It becomes the order of. Hereinafter, this cycle is also referred to as “forward rotation polarity cycle”.

  Therefore, in the control apparatus for an internal combustion engine according to this embodiment, when the crank angle signal is output, the polarity of the alternating voltage output from the generator 60 is determined, and the cycle of the determined polarity is corrected. The crankshaft 34 is determined to be forward rotation (detects forward rotation of the crankshaft 34) when the determined polarity cycle matches the forward rotation polarity cycle compared with the rotation polarity cycle. When not, the crankshaft 34 is determined to be in reverse (detection of reverse rotation of the crankshaft 34).

  10 is entered with reference to FIG. 11, assuming that the above is the case, first, in S300, the current voltage polarity REVACG0 (described later) set during the previous program execution is set to the previous voltage polarity REVACG1, and the previous program The previous voltage polarity REVACG1 set at the time of execution is set to the previous voltage polarity REVACG2, and the previous voltage polarity REVACG1 and the previous voltage polarity REVACG2 are updated.

  Next, in S302, the polarity of the AC voltage output from the generator 60 is determined (detected) at the present time (more precisely, when the crank angle signal is output). Specifically, the polarity is determined based on the comparison result signal of the comparator circuit 70d. More specifically, as shown in FIG. 11, when the AC voltage of the generator 60 is greater than the reference voltage, the polarity is positive. Is determined.

  Next, in S304, the polarity of the determined AC voltage is set (updated) to the current voltage polarity REVACG0. That is, the current voltage polarity REVACG0 means the polarity of the current AC voltage, and the previous voltage polarity REVACG1 is when the previous crank angle signal is output (for example, the time t42 when the current time is the time t43 in FIG. 11). The voltage polarity REVACG2 represents the polarity of the AC voltage when the crank angle signal was output the last time (for example, the time t41 when the current time is the time t43).

  Next, in S306, it is determined whether the bit of the second reverse rotation determination flag F_REVACG (described later) is 1. Since the initial value of the flag F_REVACG is set to 0, the process is negative when the process of S306 is executed for the first time, and the process proceeds to S308. Based on the crank stage CALSTG and the like, the crank angle is the ignition output timing at which the ignition control signal should be output ( For example, it is determined whether or not BTDC is 10 ° (crank angle reference position).

  When the result in S308 is negative, the subsequent processing is skipped. When the result is affirmative, the process proceeds to S310, and it is determined whether or not the voltage polarity REVACG2 is positive. When the result in S310 is affirmative, the process proceeds to S312 and it is determined whether or not the previous voltage polarity REVACG1 is positive. When the result is affirmative, the process proceeds to S314 and it is determined whether or not the current voltage polarity REVACG0 is negative.

  That is, S310 to S314 compare the polarity cycle of the AC voltage obtained by the processing of S300 to S304 with the polarity cycle during forward rotation (specifically, the polarity cycle consisting of positive electrode, positive electrode, and negative electrode). This is a process for determining whether or not the polarity cycle of this is coincident with the polarity cycle during forward rotation.

  In S314, in other words, in other words, when the polarity cycle of the AC voltage matches the polarity cycle during forward rotation, the crankshaft 34 is determined to be forward rotation, and the subsequent processing is skipped. On the other hand, if any of the processes of S310 to S314 is negative, that is, for example, as shown at time t46 in FIG. The shaft 34 is determined to be reverse rotation, and the process proceeds to S316, where the bit of the second reverse rotation determination flag F_REVACG is set to 1. Therefore, setting the flag F_REVACG to 1 means that the crankshaft 34 is determined to be reverse based on the period of the polarity of the AC voltage output from the generator 60, and setting it to 0 means that the crankshaft 34 This means that 34 is determined to be normal rotation.

  Next, in S318, the values of the positive voltage count counter CTACGP and the normal rotation cycle count counter CTFORWARD used in the processing described later are reset to zero.

  When it is determined that the crankshaft 34 is reversely rotated and the bit of the flag F_REVACG is set to 1, an affirmative determination is made in S306 in the next and subsequent program loops, and the flow proceeds to S320. S320 and subsequent steps are processing for determining that the crankshaft 34 has returned from reverse rotation to normal rotation.

  Explaining below, in S320, it is determined whether or not the current voltage polarity REVACG0 is negative. If the determination is negative, the process proceeds to S322, and the value of the positive voltage count counter CTACGP is incremented by one. Since the process of S322 is repeatedly executed until it is affirmed in S320, the value of the counter CTACGP is determined to be positive in the program loop before the current AC voltage is determined to be negative in S320 (specifically, Means the number of times denied in S320.

  When the result in S320 is affirmative, the program proceeds to S324, in which it is determined whether or not the value of the positive voltage count counter CTACGP is 2. That is, in S320 and S324, whether or not the polarity of the AC voltage is currently determined to be negative and whether or not it has been determined to be positive in the previous two program loops, in other words, the polarity cycle of the AC voltage is positive. This is a process for determining whether or not it coincides with the rotating polarity cycle (specifically, a polarity cycle comprising a positive electrode, a positive electrode, and a negative electrode).

  If the result in S324 is negative, that is, if they do not match (for example, at the time t47 or t48 in FIG. 11), the process proceeds to S326, and the value of the normal rotation cycle counter CTFORWARD is reset to 0, while when it is affirmed (when they match). In FIG. 11, assuming that the actual crankshaft 34 returns to normal rotation at time t49 (at time t50), the process proceeds to S328, and the value of the counter CTFORWARD is incremented by one. Therefore, the counter CTFORWARD indicates the number of times that the crankshaft 34 is determined to be the same after the crankshaft 34 is determined to be reverse.

  Next, in S330, the value of the positive voltage counter CTACGP is reset to 0, and in S332, it is determined whether or not the value of the forward rotation cycle counter CTFORWARD is equal to or greater than a predetermined number (specifically, twice). For example, it is determined whether or not the number of times determined to match has reached a predetermined number. When the result in S332 is negative, the subsequent processing is skipped, while when the result is affirmative (at time t51 in FIG. 11), it is determined that the crankshaft 34 has surely returned from reverse rotation to normal rotation, and the flow proceeds to S334. The bit of the second reverse rotation determination flag F_REVACG is set to 0.

  Returning to the description of FIG. 4, the process then proceeds to S <b> 18, where the process of determining the reverse rotation or normal rotation return determination of the crankshaft 34 performed in S <b> 14 or S <b> 16 is performed.

  FIG. 12 is a sub-routine flowchart of the reverse rotation / forward rotation determination determination process.

  As shown in FIG. 12, first, in S400, it is determined whether or not the bit of the second reverse rotation determination flag F_REVACG is 1. When the result in S400 is affirmative, the program proceeds to S402, in which the bit of the history flag F_RVACGRCD (initial value 0) is set to 1. That is, when the bit of the flag F_RVACGRCD is set to 1, there is a history that the crankshaft 34 has been determined to be reverse in the second reverse rotation / forward rotation determination processing, and that 0 is set to that history. Means no.

  Next, in S404, it is determined whether or not the bit of the reverse rotation detection confirmation flag F_REVERSE is 1. Since the initial value of the flag F_REVERSE is set to 0, when the process of S404 is executed for the first time, the result is negative and the process proceeds to S406, and the bit of the flag F_REVERSE is set to 1. When the bit of the flag F_REVERSE is 0, the engine 10 is ignited and fuel is injected in a process described later, whereas when it is 1, the ignition and fuel is prohibited.

  Next, in S408, the bits of the reference position detection flag F_TCTDC and the reference projection detection flag F_LONG are set to 0 to prepare for the normal rotation return determination process performed by detecting the crank angle reference position. If the bit of the flag F_REVERSE is set to 1 in S406, the next and subsequent program loops are affirmed in S404, and the processing of S406 and S408 is skipped.

  On the other hand, when the result in S400 is negative, the program proceeds to S410, in which it is determined whether the bit of the history flag F_RVACGRCD is 1. When the result in S410 is negative, the program proceeds to S412 to determine whether or not the bit of the first reverse rotation determination flag F_REVCRK is 1. When the result in S412 is affirmative, the processing proceeds to the above-described processing of S404 to S408. When the bit of the flag F_REVERSE is 0, it is set to 1 at S406, and when it is 1, the program is terminated as it is.

  As described above, when the crankshaft 34 is determined to be reverse in at least one of the first and second reverse rotation / normal rotation return determination processes with different reverse rotation determination conditions (specifically, the first and second reverse rotations). When at least one of the determination flags F_REVCRK and F_REVACG is 1), the flag F_REVERSE bit is set to 1 to confirm the reverse rotation detection of the crankshaft 34, and the ignition and fuel injection of the engine 10 are prohibited.

  In the program loop after the ignition and fuel injection of the engine 10 are prohibited, when the result in S400 is negative, that is, in the second reverse rotation / forward rotation return determination process, it is determined that the crankshaft 34 has returned from reverse rotation to forward rotation. If the bit of the second reverse rotation determination flag F_REVACG is changed from 1 to 0, the process proceeds to S410.

  Since the bit of the history flag F_RVACGRCD still remains 1, the determination in S410 is affirmed and the process proceeds to S414, and the bit of the first reverse rotation determination flag F_REVCRK is set to 0. In other words, after the ignition of the engine 10 is prohibited, when the crankshaft 34 is determined to return to the normal rotation in the second reverse rotation / forward rotation determination process, the result of the first reverse rotation / forward rotation determination process is the result. Regardless, the bit of the first reverse rotation determination flag F_REVCRK is set to 0.

  Next, the process proceeds to S416, where the bit of the reverse rotation detection confirmation flag F_REVERSE is set to 0, and the process proceeds to S418, where the bit of the history flag F_RVACGRCD is set to 0.

  Further, in the program loop after the ignition and fuel injection of the engine 10 are prohibited, when the result in S412 is negative, that is, in the first reverse rotation / forward rotation return determination process, the crankshaft 34 has returned from reverse rotation to forward rotation. When the bit of the first reverse rotation determination flag F_REVCRK changes from 1 to 0, the processing from S414 to S418 described above is executed.

  As described above, after the ignition of the engine 10 and the fuel injection are prohibited, the crankshaft 34 is rotated from the reverse rotation to the normal rotation in at least one of the first and second reverse rotation / normal rotation return determination processes having different normal rotation return determination conditions. When it is determined that the state has returned to (specifically, when at least one of the first and second reverse rotation determination flags F_REVCRK and F_REVACG is changed from 1 to 0), the bit of the flag F_REVERSE is set to 0 in S416. Then, the reverse rotation detection of the crankshaft 34 is canceled, and the prohibition of ignition of the engine 10 and the prohibition of fuel injection are canceled as will be described later.

  Next, in the flowchart of FIG. 4, the process proceeds to S20 to perform an ignition output process, and proceeds to S22 to perform a fuel injection process.

  FIG. 13 is a sub-routine flowchart showing the ignition output process, and FIG. 14 is a sub-routine flowchart showing the fuel injection process.

As shown in FIG. 13, the engine rotational speed NE is calculated (detected) based on the output of the crank angle sensor 54 at S500, the opening degree θTH of the throttle valve 14 based on the output of the throttle opening sensor 44 proceeds to S502 Calculate (detect). Next, in S504, based on the calculated engine speed NE and the throttle opening θTH, a preset map value is searched to calculate the ignition timing.

  Next, the process proceeds to S506 to determine whether or not the crank angle is the ignition output timing. When the determination is negative, the subsequent processing is skipped, while when the determination is affirmative, the process proceeds to S508, where the bit of the reverse rotation detection confirmation flag F_REVERSE is 1 or not. Judge.

  If the result in S508 is negative, that is, if it is determined that the crankshaft 34 is rotating forward or has returned from rotating in the reverse direction, the process proceeds to S510, and an ignition control signal is output so that ignition is performed at the calculated ignition timing. To do. On the other hand, when the result in S508 is affirmative, that is, when it is determined that the crankshaft 34 is reverse, the process proceeds to S512, and the output of the ignition control signal is prohibited, in other words, the ignition of the engine 10 is prohibited.

  In the fuel injection process, as shown in FIG. 14, in S600, a map value set in advance is searched from the engine speed NE, the throttle opening θTH, etc., and the fuel injection amount and the fuel injection timing are calculated. Next, the process proceeds to S602, where it is determined whether or not the fuel injection timing at which the crank angle has been calculated. When the determination is negative, the subsequent processing is skipped, while when the determination is affirmative, the process proceeds to S604, where the bit of the reverse rotation detection confirmation flag F_REVERSE is set. Judge whether 1 or not.

  When the result in S604 is negative, the program proceeds to S606 and outputs a fuel injection control signal for injecting fuel from the injector 20, while when the result is affirmed, the program proceeds to S608 and prohibits the output of the fuel injection control signal, in other words, the engine. 10 fuel injection is prohibited.

  FIG. 15 is a flow chart showing the operation of the control device for the internal combustion engine executed by the ECU 70 every predetermined time, for example, every 5 msec, in parallel with the flow chart of FIG.

  To explain below, in S700, it is determined whether or not a crank angle signal has been input from the crank angle sensor 54 from the previous program execution to the current program execution. When the result in S700 is affirmative, the subsequent processing is skipped, while when the result is negative, the process proceeds to S702 to determine whether or not the engine 10 is stopped. More precisely, whether or not the crankshaft 34 is completely stopped. to decide. In S702, when the crank angle signal is not input from the crank angle sensor 54 for a predetermined time (for example, 200 msec), it is determined that the engine 10 is stopped.

  When the result in S702 is negative, the program is terminated as it is. When the result is affirmative, the program proceeds to S704, the bits of the reference position detection flag F_TCTDC and the reference protrusion detection flag F_LONG are set to 0, and the process proceeds to S706 to confirm the reverse rotation detection flag. The bits of F_REVERSE, first and second reverse rotation determination flags F_REVCRK, F_REVACG are set to 0. Thus, when the engine 10 is stopped, the bit of each flag is set to 0 to cancel the ignition prohibition / fuel injection prohibition and prepare for the next program execution.

As described above, according to the embodiment of the present invention, a plurality of reverse rotation determination means for determining that the crankshaft 34 of the internal combustion engine (engine) 10 has reversed from the rotation in the normal rotation direction based on different reverse rotation determination conditions. (ECU 70. First and second reverse rotation / normal rotation return determination processing S14, S16), when the crankshaft 34 is determined to be reverse rotation in at least one of the plurality of reverse rotation determination means, ignition of the internal combustion engine Ignition prohibiting means for prohibiting the engine (ECU 70. S14 to S20, S210, S316, S406, S508, S512), and after the ignition prohibiting means prohibits ignition of the internal combustion engine, the crankshaft is changed from reverse to forward rotation. A plurality of normal rotation return determination means for determining that the vehicle has returned based on different normal rotation return determination conditions (ECU 70; first and second reverse rotation / normal rotation return determination processing); .S10～S16) Bei example, said when the crank shaft 34 in at least one of the plurality of forward recovery judgment means is determined to have returned from the reverse rotation to the normal rotation, the prohibition of the ignition of the internal combustion engine is released (S14 to S20, S208, S334, S416, S508, S510).

  As described above, when the crankshaft 34 is determined to be reverse in at least one of the plurality of reverse rotation determination means having different reverse rotation determination conditions, the ignition of the engine 10 is prohibited. Thus, the ignition can be prohibited and the reverse rotation load does not act on the crankshaft 34 and the like, and the engine body can be prevented from being damaged.

  When it is determined that the crankshaft 34 has returned from the reverse rotation to the normal rotation in at least one of a plurality of normal rotation return determination means having different normal rotation return determination conditions after the ignition of the engine 10 is prohibited. The prohibition of ignition is canceled, that is, the prohibition of ignition is canceled when the crankshaft 34 is determined to return to normal rotation in at least one of the plurality of normal rotation return determination means instead of all of the plurality of normal rotation return determination means. Therefore, the cancellation of the ignition prohibition can be executed at an appropriate timing at an early stage, and thus the restartability can be improved.

Also, a crank angle signal output means (crank angle sensor 54) for outputting a crank angle signal at every predetermined crank angle of the crankshaft 34, and an AC generator 60 driven by the rotation of the crankshaft 34 to output an AC voltage. And a polarity determination means (ECU 70, S16, S302) for determining the polarity of the AC voltage output from the AC generator 60 when the crank angle signal is output, and a plurality of reverse rotation determination means. At least one of the crankshaft when the determined polarity cycle and the polarity cycle at the time of forward rotation to be output from the AC generator 60 when the crankshaft 34 is rotated in the forward rotation direction do not coincide with each other. 34 while determining the reverse (S16, S310~S316), at least one of said plurality of forward recovery determination means, After ignition of the internal combustion engine is prohibited by the serial ignition prohibition means, when said determined period of polarity coincides with the forward rotation time of polarity period, determines that the crankshaft 34 is restored from the reverse rotation to the normal rotation Since the prohibition of ignition of the internal combustion engine is canceled (S16, S306, S320 to S334), it is possible to more accurately detect that the crankshaft 34 has been reversely rotated and has returned from normal to reverse. it can.

  A plurality of protrusions 60g (reference protrusions 60g1, protrusions 60g2) having a predetermined circumferential length and arranged at equiangular intervals on the circumference of the rotor 60a rotating in conjunction with the crankshaft 34 A protrusion position signal output means disposed at a stationary position (crankcase 10a) opposite to the protrusion 60g and outputting a front end position signal and a rear end position signal indicating a front end position and a rear end position of the protrusion 60g (crank angle); Sensor 54) measures the protrusion elapsed time TCPRJ from when the front end position signal is output to when the rear end position signal is output, and the front end position signal of the next protrusion 60g after the rear end position signal is output. A time measuring means (ECU 70; S10, S100 to S114) for measuring the elapsed time TCDENT between the protrusions until it is output; At least one of them is determined that the crankshaft 34 is reverse based on the measured protrusion elapsed time TCPRJ and the protrusion-to-protrusion elapsed time TCDENT (S14, S202 to S206, S210), and the plurality of normal rotation return determination means At least one of the above is that after the ignition of the internal combustion engine is prohibited by the ignition prohibiting means, the crankshaft 34 returns from the reverse rotation to the normal rotation based on the measured protrusion elapsed time TCPRJ and the protrusion elapsed time TCDENT. (S10, S14, S118 to S136, S200, S208, S212). As a result, it is possible to more accurately detect that the crankshaft 34 has been reversely rotated and has returned from the reverse rotation to the normal rotation.

  The time measuring means measures the protrusion elapsed time TCPRJ and the protrusion-to-projection elapsed time TCDENT every time the front end position signal and the rear end position signal of the protrusion 60g are output (S10, S100 to S114). The reverse rotation determination means, when the ratio (second ratio RTCDENT) of the inter-projection elapsed time TCDENT measured this time and the last measured inter-projection elapsed time (previous inter-projection elapsed time TCDENT1) is greater than or equal to the first predetermined value, Alternatively, when the ratio (third ratio RTCPRJ) of the protrusion elapsed time TCPRJ measured this time to the previously measured protrusion elapsed time (previous protrusion elapsed time TCPRJ1) is equal to or greater than a second predetermined value, the crankshaft 34 is rotated in reverse. Since it is configured to determine (S14, S202 to S206, S210), the fact that the crankshaft 34 has reversed is further corrected. It can be detected in.

  Further, any one of the plurality of protrusions 60g includes a forward rotation determination protrusion (reference protrusion 60g1) formed so that the circumferential length thereof is different from that of the remaining protrusion 60g2, and the time measuring means Measuring the protrusion elapsed time TCPRJ and the protrusion-to-projection elapsed time TCDENT every time the front end position signal and the rear end position signal of the protrusion are output (S10, S100 to S114), The ratio of the protrusion elapsed time TCPRJ and the protrusion-to-projection elapsed time TCDENT measured this time (first ratio RTCPD), and the ratio of the protrusion protrusion time TCPRJ1 and the protrusion-to-projection elapsed time TCENT1 measured last time (previous first ratio RTCPD1) When the forward rotation determination projection 60g1 is detected based on the calculated change amount, Link shaft 34 is configured to determine that the return from the reverse rotation to the normal rotation (S10, S14, S118~S136, S200, S208, S212). As a result, it is possible to more accurately detect that the crankshaft 34 has returned from the reverse rotation to the normal rotation, and the ignition prohibition can be canceled at a more appropriate timing.

  In addition, when at least one of the plurality of reverse rotation determination means determines that the crankshaft 34 is reverse rotation, the crankshaft 34 includes fuel injection prohibiting means for prohibiting fuel injection of the internal combustion engine (engine) 10 (ECU 70, S14, S14). S16, S22, S210, S316, S406, S604, S608), the fuel injection prohibiting means determines that the crankshaft 34 has returned from reverse to normal rotation in at least one of the plurality of normal rotation return determination means. In this case, the prohibition of fuel injection of the internal combustion engine is canceled (S14, S16, S22, S208, S334, S416, S604, S606).

  As described above, when the crankshaft 34 is determined to be reverse rotation in at least one of the plurality of reverse rotation determination means, the fuel injection of the engine 10 is prohibited, so that a load due to the reverse rotation acts on the crankshaft 34 and the like. This can prevent the engine body from being damaged more reliably.

  Further, when it is determined in at least one of the plurality of normal rotation return determination means that the crankshaft 34 has returned from the reverse rotation to the normal rotation, the prohibition of fuel injection of the engine 10 is canceled, that is, the plurality of normal rotation return determination means. Since it is configured to cancel the prohibition of fuel injection when the crankshaft 34 is determined to return to the normal rotation in at least one of the rotation recovery determination means, at least one of them, the fuel injection prohibition is canceled at an appropriate timing early. Therefore, restartability can be further improved.

  In the above description, the forward polarity polarity cycle is a polarity cycle composed of a positive electrode, a positive electrode, and a negative electrode. However, these are merely examples, and needless to say, the polarity cycle is appropriately changed according to the specifications of the generator 60.

  In addition, although the circumferential length of the reference protrusion 60g1 is longer than that of the other protrusion 60g2, the reference protrusion 60g1 may be configured to be shorter. Is formed so that the circumferential length thereof is different from that of the remaining protrusions. " In that case, the first and second determination threshold values A and B and the first and second predetermined values are appropriately changed.

  Moreover, although the predetermined number of times compared with the normal rotation period counter CTFORWARD and the exhaust amount of the engine 10 are shown by specific numerical values, these are examples and are not limited.

  In addition, although a motorcycle has been described as an example of the vehicle, the present invention is not limited thereto. For example, a so-called saddle type vehicle in which a driver rides over a seat (saddle) such as a scooter or an ATV (All Terrain Vehicle). Any other vehicle (for example, a four-wheeled vehicle) may be used.

  10 engine (internal combustion engine), 34 crankshaft, 54 crank angle sensor, 60 AC generator, 60a rotor, 60g protrusion, 60g1 reference protrusion (forward rotation determination protrusion), 60g2 (residual) protrusion, 70 ECU (electronic control) unit)

Claims (5)

The crankshaft is determined to be reverse in at least one of a plurality of reverse rotation determination means for determining that the crankshaft of the internal combustion engine has been reversed from rotation in the forward rotation direction based on different reverse rotation determination conditions Different from the fact that the crankshaft has returned from normal to reverse after the ignition is prohibited by the ignition prohibiting means and the ignition prohibiting means for prohibiting ignition of the internal combustion engine. Bei example a plurality of forward return determination means for determining based on the determination condition, when the crank shaft at least one of the plurality of forward recovery judgment means is determined to have returned from the reverse rotation to the normal rotation, the a control apparatus for an internal combustion engine in which the prohibition of the ignition of the internal combustion engine is Ru is released, further click for outputting a crank angle signal every predetermined crank angle of the crankshaft A crank angle signal output means, an AC generator driven by rotation of the crankshaft to output an AC voltage, and a polarity of the AC voltage output from the AC generator when the crank angle signal is output At least one of the plurality of reverse rotation determination means to be output from the AC generator when the determined polarity period and the crankshaft are rotated in the forward rotation direction. When the forward rotation polarity cycle does not match, the crankshaft is determined to be reverse rotation, and at least one of the plurality of normal rotation return determination means is, after ignition of the internal combustion engine is prohibited by the ignition prohibition means, When the determined polarity cycle coincides with the forward polarity polarity cycle, it is determined that the crankshaft has returned from reverse rotation to normal rotation, and the prohibition of ignition of the internal combustion engine in the previous period is resolved. The control device for an internal combustion engine, characterized by. A plurality of protrusions disposed at equiangular intervals on the circumference of the rotor rotating in conjunction with the crankshaft, and disposed at equiangular intervals; Projection position signal output means for outputting the front end position signal and the rear end position signal indicating the front end position and the rear end position of the protrusion, and the protrusion elapsed time from the output of the front end position signal to the output of the rear end position signal. And a time measuring means for measuring an elapsed time between protrusions from when the rear end position signal is output until a front end position signal of the next protrusion is output, and at least of the plurality of reverse rotation determination means One of the crankshafts is determined to be reverse based on the measured protrusion elapsed time and the inter-projection elapsed time, and at least one of the plurality of forward rotation return determination means is the internal combustion engine by the ignition prohibition means. After ignition of the function is prohibited, the internal combustion according to claim 1 Symbol mounting the crankshaft on the basis of the measured projections elapsed time between protrusions elapsed time and judging that it has returned from the reverse rotation to the normal rotation Engine control device. The time measuring means measures the protrusion elapsed time and the protrusion elapsed time each time the protrusion front end position signal and the rear end position signal are output, and the reverse rotation determination means is configured to measure the interprotrusion elapsed time measured this time. When the ratio between the time and the previously measured protrusion elapsed time is greater than or equal to the first predetermined value, or when the ratio between the protrusion elapsed time measured this time and the previously measured protrusion elapsed time is greater than or equal to the second predetermined value, 3. The control apparatus for an internal combustion engine according to claim 2, wherein the crankshaft is determined to be reverse. Any one of the plurality of protrusions includes a forward rotation determination protrusion formed so that a circumferential length thereof is different from that of the remaining protrusions, and the time measuring means includes a front end position signal of the protrusion Each time the rear end position signal is output, the projection elapsed time and the projection elapsed time are measured, and the normal rotation return determination means measures the ratio of the projection elapsed time and the projection elapsed time measured this time and the previous measurement. When the forward rotation determination protrusion is detected based on the calculated change amount, a change amount between the projected protrusion time and the ratio of the protrusion elapsed time is calculated. control apparatus for an internal combustion engine according to claim 2 or 3, wherein the determining has been restored with. When at least one of the plurality of reverse rotation determination means, the crankshaft is determined to be reverse rotation, the fuel injection prohibiting means for prohibiting fuel injection of the internal combustion engine is provided. If the crankshaft at least one of the rolling recovery judgment means is determined to have returned from the reverse rotation to the normal rotation, any one of claims 1-4, characterized in that to release the prohibition of the fuel injection of the internal combustion engine The control apparatus of the internal combustion engine described in 1.

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