JPH0979125A - Reverse rotation preventive method and device for two-cycle fuel injection type internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop an engine to stop reverse rotation at starting time, and improve restartabilithy thereafter by arranging a reverse rotation detecting means of the engine, stopping ignition when reverse rotation is detected, and continuing fuel injection. SOLUTION: Fuel injection means #1 to #6 being output side injectors, ignition means #1 to #6, a fuel pump and an oil pump are controlled in driving on the basis of an operation result of respective control quantities in an arithmetic operation processing device. Cylinder detecting signals of cylinder detecting means #1 to #6 are inputted in order to the arithmetic operation processing device with every prescribed crank angle in response to respective cylinders. A cylinder number of its inputted cylinder detecting signal and a cylinder number of the cylinder detecting signal inputted at the last time are compared with each other, and the engine rotating direction is discriminated. When it reversely rotates, ignition is stopped in cylinders not less than the prescribed number, on the one hand, fuel injection is continued. Therefore, restartability thereafter can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronically controlled multi-cylinder internal combustion engine, and more particularly to a method for detecting engine reversal at the time of starting and a method for coping with it.

[0002]

2. Description of the Related Art In a fuel injection type internal combustion engine, a cylinder detection signal (pulsar signal) is sequentially input to a control device for each cylinder at a predetermined crank angle as the engine rotates, and the pulsar signal is input to the cylinder detection signal. Based on this, the ignition timing and the fuel injection timing are controlled. However, when the engine is cranked, the output level of the pulser signal is low due to the low rotation speed, which may cause erroneous detection or malfunction due to noise. If the pulsar signal is erroneously detected or malfunctions during cranking, the ignition timing is shifted, and if this is significant, the engine may rotate in the reverse direction. When such reverse rotation occurs, it is necessary to stop the engine once to restore normal operation.

Therefore, in the conventional four-cycle engine, when the reverse rotation at the time of start is detected, the pulsar signal is failed to stop both the ignition and the fuel injection to stop the engine.

On the other hand, in a two-cycle engine, since the cylinder burns once per revolution, there is a high possibility that the cylinder will rotate in reverse if the ignition timing is significantly deviated. Therefore, it has been required to adopt a similar engine reversal countermeasure method at the time of starting. . That is, when cranked by the starter motor, air is sucked into the crank chamber from the intake passage, and directly into the crank chamber or the scavenging passage or into the intake passage to the crank chamber based on the pulsar signal generated by cranking. The fuel is injected and the fuel is vaporized to form a mixture with air and reaches the combustion chamber, where it is ignited and burned by the spark of the spark plug at a predetermined timing based on the pulsar signal. If this initial explosion causes reverse rotation because the ignition timing is incorrect due to the low output level or noise of the pulsar signal as described above, reverse rotation is detected, and the pulsar signal is failed to cause both ignition and fuel injection. It stops and stops the engine.

[0005]

However, until the engine is stopped, air is sucked into the crank chamber from the intake passage, the air is scavenged into the combustion chamber through the scavenging passage, and the air is compressed and expanded. A cleaning cycle of the crank chamber, the scavenging passage, and the combustion chamber by the air that is exhausted after that is performed. Therefore, when the engine is restarted after being stopped, even if fuel injection is performed along with ignition, the injected fuel does not vaporize immediately because the engine temperature is low, and the intake passage, crank chamber, scavenging passage It took a long time for the proper mixture to arrive at the combustion chamber due to the adherence to the wall surface, etc. As a result, there was a problem that the restartability after the reverse rotation stop was not good.

By the way, in order to carry out reverse rotation detection and reverse rotation stop in one circuit, it is conceivable to mask the ignition circuit and configure the circuit so that there is no ignition output during reverse rotation.

FIG. 16 is a diagram for explaining the operation of such a mask circuit. At the time of normal rotation of the engine, a timer is set by using an engine rotation signal (pulsar signal) corresponding to each cylinder as a trigger, and an ignition pulse signal is sequentially output substantially in synchronization with the engine rotation signal of the next cylinder. At this time, a mask signal (charge coil signal in the figure) for the charge coil for charging the capacitor of the ignition coil is output. This charge coil signal is a pulse signal that repeats H and L at an input interval of a pulser signal that is known in advance (for example, a crank angle interval of 60 degrees in the case of 6 cylinders). Keep in sync. The circuit is configured so that the ignition signal based on the pulsar signal is not output when the charge coil signal is at the L level.

During reverse rotation, the engine rotation signal and the charge coil signal are out of phase, and the pulse of the engine rotation signal is synchronized with the L level of the charge coil signal. Therefore, no ignition pulse is output and the engine stops.

However, when such a mask circuit is used, the structure of the control circuit becomes complicated, the number of hardware components increases, the cost increases, and the reliability of the operation may be problematic.

The object of the present invention is, in a two-cycle internal combustion engine in which fuel is injected upstream of a crank chamber including a scavenging passage, even if reverse rotation occurs at the time of start, the engine is stopped so as to stop the reverse rotation, and thereafter, An object of the present invention is to provide an engine stop control method at the time of reverse rotation that improves startability.

Another object of the present invention is to provide a reverse rotation stop control device for stopping the engine at the time of reverse rotation, which can surely detect the reverse rotation and stop the engine with a simple structure without using special rotation.

[0012]

In order to achieve the above object, in the present invention, fresh air is supplied to a combustion chamber through an intake passage, a crank chamber and a scavenging passage, and fuel is injected to a portion upstream from the combustion chamber. In a two-cycle fuel injection type internal combustion engine in which an injector and an ignition plug are arranged in a combustion chamber, ignition is performed at an ignition timing according to an operating state based on a pulser signal, and fuel is injected, the engine reverse rotation detecting means. Is provided, and when the reverse rotation is detected, the ignition is stopped while the fuel injection is continued, and the reverse rotation preventing method of the two-cycle fuel injection type internal combustion engine is provided.

Further, in the present invention, in each of the plurality of cylinders, fresh air is supplied to the combustion chamber through the intake passage, the crank chamber and the scavenging passage, and the injector for injecting fuel to the upstream portion of the combustion chamber and the combustion chamber. An ignition plug is arranged to ignite the ignition plug of each cylinder at an ignition timing according to the operating state based on at least one of the cylinder detection signals corresponding to each cylinder, and to inject fuel from the injector of each cylinder. A control device for controlling the cylinders is arranged, and the cylinder detection signals are sequentially input to the control device in correspondence with each cylinder for each predetermined crank angle according to the engine rotation, and the cylinder number of the input cylinder detection signal and the previous time are input. The engine rotation direction is determined by comparing it with the cylinder number of the input cylinder detection signal. If the engine rotation direction is reversed, ignition is stopped in a predetermined number or more of cylinders. , Fuel injection was to be continued for 2
A method for preventing reverse rotation of a cycle fuel injection type internal combustion engine is provided.

The present invention further comprises various operating state detecting means, ignition means, fuel injection means, and a control device for calculating the ignition timing and the fuel injection amount according to the operating state according to a predetermined program, A cylinder detection signal is sequentially input to the control device for each cylinder at a predetermined crank angle as the engine rotates, and the control device inputs the cylinder number of the input cylinder detection signal and the previous input. A two-cycle fuel injection in which the engine rotation direction is determined by comparing it with the cylinder number of the cylinder detection signal, and if the engine is in reverse, ignition is stopped in a predetermined number of cylinders or more while fuel injection is continued. A reverse rotation preventing device for a rotary internal combustion engine is provided.

[0015]

When the reverse rotation is detected, the ignition is stopped and the fuel injection is continued. Therefore, the air-fuel mixture is supplied to the combustion chamber, but no sparks are blown from the spark plug, combustion does not occur, no output is generated, inertia energy is consumed by load or friction, and the engine stops. Fuel injection is continued even when the engine is stopped, and while the fuel is injected from the point where the fuel is injected to the combustion chamber, it is filled with the air-fuel mixture, and the wall surface in the middle is filled with the fuel film that cannot be vaporized. It is in a state of adhering to the shape. When the engine is restarted after being stopped, the air-fuel mixture immediately enters the combustion chamber, and the fuel adhering in the form of a liquid film is immediately vaporized to form the air-fuel mixture, which continuously enters the combustion chamber.

Further, the control device performs the reverse rotation detection as follows.

The cylinder number of the pulsar signal input is detected by the cylinder detection signal (pulser signal) sequentially input from each cylinder. This cylinder number is compared with the cylinder number of the pulser signal input last time. If it is in a predetermined number order, it is determined to be normal rotation, and if the order is reverse, it is determined to be reverse rotation. Therefore, reverse rotation can be detected if there are two pulser signals after engine cranking has started. That is, a complicated circuit is not required to detect the reverse rotation. Moreover, the adverse effect on the engine load due to the reverse rotation can be shortened. For example, in the case of a 6-cylinder engine, the pulsar signal interval is 60 degrees, and therefore the reverse rotation can be detected by 120 degrees of crankshaft rotation. When the reverse rotation is detected, the engine stop processing is immediately performed. The stop processing is performed by stopping the ignition output and the fuel injection.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an external view of a two-machine outboard motor for a ship to which the present invention is applied. As shown in the figure, the outboard motors 406-1 and 40-1 including two engines at the stern of the hull 405.
6-2 is attached. This is a structure for obtaining sufficient propulsive force on the sea, and for enabling navigation even if one of the outboard motors is out of order and ensuring return to the port.

When two outboard motors are cruising as described above, the engines are operated in a two-engine running state. When performing drive control of the two-engine engine, each engine needs to be able to operate independently, and therefore each engine has a drive control device. Each control device detects various operating states such as engine speed, throttle opening, accelerator position, so-called load such as intake pipe negative pressure, intake air temperature, exhaust gas oxygen concentration, shift position, etc., and based on this detection information. ,
The optimum air-fuel ratio, the fuel injection amount, the injection timing, the ignition timing, etc. at that time are calculated according to a predetermined control program, and the engine is drive-controlled based on the calculated values. In this case, the control program has a detection information read routine and a main routine in which a plurality of calculation routines for calculating each control amount based on the read detection information are arranged in accordance with a predetermined sequence. Arithmetic processing is performed.

FIG. 2 is a detailed view of the engine around one of the V-type 6-cylinder engines mounted on each of the above-mentioned two-engine outboard motors.

As shown in FIG. 2, in the crank chamber 22,
The intake port 80 communicating with the intake manifold 24 opens. The intake port 80 is provided with the reed valve 23. The intake manifold 24 is provided with an injector 26 and a throttle valve 25. Intake manifold 24
An intake air temperature sensor 32 is provided in the. A throttle opening sensor 15 is provided on the throttle valve 25 outside the intake manifold 24.

The fuel supplied to the injector 26 is stored in the fuel tank 63. This fuel tank 63
The fuel inside is sent to the sub tank 67 by the bottom pressure fuel pump 64 through the water separation and dust removal filter 66. The fuel in the sub-tank 67 is sent to the injector 26 of each cylinder via the distribution pipe by the high-pressure fuel pump 65, and the fuel is injected into the intake manifold 24 at a controlled injection amount and injection timing as will be described later, and a predetermined air-fuel ratio is obtained. To form a mixture of. The high-pressure fuel that has not been injected by the injector 26 passes through the return pipe 70 and the sub-tank 6
Recovered to 7. A pressure regulator 69 is provided on the return pipe 70 to keep the injection pressure of the injector 26 constant. Thereby, the fuel injection amount can be controlled by controlling the injection time by opening the injector 26.

FIG. 3 is a block diagram of the drive operation system for the throttle and gear shift of one of the two outboard motors. The outboard motor main body 38 is mounted on the tilt shaft 3 with respect to the hull 36 via a bracket 37a and a clamp bracket 37b.
The trim angle θ can be changed around 05. 30
6 is a variable trim angle actuator, and 39 is a trim angle sensor. The trim angle θ indicates how much the direction of the central axis of the propeller 10 is inclined from the ship bottom. When the trim angle is 0 °, that is, when the central axis of the propeller 10 is parallel to the bottom of the outboard motor, the outboard motor is generally formed so that the front edge of the outboard motor body 38 is aligned with the vertical line. The relative angle θ with respect to the line may be called a trim angle.

Shift lever 50 having a cam 51 at its end
Is connected to the link bar 53 in the cowling via a pivot piece 52. The cam 51 is for shifting a clutch connecting the engine and the propeller shaft. A pin 55 is provided so as to project from the end of the link bar 53. The pin 55 is slidably mounted as shown by an arrow A in the long hole guide 54 fixed in the cowling.

On the other hand, a remote control box 56 for gear shift and throttle operation is provided inside the outboard motor 406-.
Two are provided for 1,406-2. This remote control box 56 is provided with the shift cable 5 for the outboard motor body 38.
7, throttle cable 58 and electric signal cable 5
It can be connected via three cables of 9. The shift cable 57 is connected to the pin 55 of the above-mentioned link bar 53 in the cowling. The remote control box 56 is provided with an operation lever 60, which is operated to move forward or backward from the neutral position (N) to slide the pin 55 in the elongated hole ring 54 via the shift cable 57. As a result, the link bar 53 moves in parallel, and the pivot piece 52 at the base portion thereof is rotated as shown by arrow B. As a result, the shift lever 50 rotates about its axis, and the cam 51 rotates to connect the crankshaft and the forward gear or the reverse gear via the dog clutch. The operating lever 60 is further moved in the F direction (during forward travel) or the R direction (during reverse travel) from the forward or backward shift operation completion position, that is, the throttle valve fully closed position, so that the inside of the outboard motor 38 is passed through the throttle cable 58. The engine throttle valve operates in the fully open direction. The shift cable 57 is provided with a shift cut switch (not shown). This is because when the dog clutch is disengaged from the gear during high-load operation, the meshing surface pressure between the clutch and the gear becomes very large, so that the cable is heavily loaded. The shift cut switch is for detecting an excessive clutch engagement pressure by detecting the elastic deformation amount of the cable due to this load, and lowering the engine rotation to facilitate clutch switching. Such a shift cut switch may be provided inside the cowling or inside the remote control box.

The remote control box 56 is further provided with a falling water detection switch (not shown). This water drop detection switch is, for example, connected to a wire tied to the body of an occupant, and when the occupant drops water, the switch is operated to stop the engine and immediately stop the ship. The remote control box 56 is also provided with an independent engine stop operation switch (not shown).

FIG. 4 shows the details of the drive control system including the detection means for detecting various operating states of the outboard motor including the above-mentioned engine and the means for driving fuel injection and ignition. This example represents one control system of an outboard motor equipped with two 6-cylinder engines for ships.

Six cylinder detecting means # 1 to # 6 are arranged around the crankshaft, and generate a trigger signal for executing an event interrupt (TDC interrupt) for each cylinder executed in the main routine. This is configured so that, for example, a signal is emitted at the moment when the piston of each cylinder is located at the top dead center or before this by a predetermined angle (crank angle). Therefore, in this embodiment, 60 times during one rotation of the crankshaft.
One cylinder detection signal (TDC signal) for each cylinder #
The data are sequentially sent to the arithmetic processing unit from 1 to # 6. In this event interruption flow, ignition and fuel injection are performed based on the control calculation result for each cylinder determined during the main routine.

The crank angle detecting means emits an angle pulse which serves as a base for ignition timing control, and emits a pulse signal corresponding to the number of teeth of the ring gear engaged with the crankshaft. For example, 4 in 1 rotation corresponding to 112 gear teeth
If it is configured to emit 48 pulses, the crankshaft rotates 0.8 degrees for each pulse.

The throttle opening detecting means 15 issues an analog voltage signal according to the opening of the throttle valve 25 provided in the intake manifold 24. The arithmetic processing unit A / D-converts this analog signal and performs arithmetic processing such as map reading.

More specifically, the link of the throttle wire connected to the above-mentioned throttle lever 60 (FIG. 2) is connected to one end of the valve shaft of the throttle valve 25.
A resistance sliding sensor is attached to the opposite end of the valve shaft. The valve shaft rotates according to the opening of the throttle valve, and the resistance value of the sensor changes. This change in resistance value is extracted as a voltage change and used as a detection signal of the throttle opening.

From the next trim angle detecting means to intake air temperature detecting means, when there is a change in the environment with respect to the operating conditions of the engine, the control amount is corrected according to this change. The trim angle detection means detects the mounting angle of the outboard motor. The E / G temperature detecting means attaches a temperature sensor to the cylinder block of each cylinder (or a specific reference cylinder) to detect the temperature of that cylinder.
The atmospheric pressure detecting means is provided at an appropriate position in the cowling. The intake air temperature detecting means 32 is provided at an appropriate position on the intake passage. The atmospheric pressure and the intake air temperature directly affect the volume of air, and the arithmetic processing unit performs a correction operation for the control amount such as the air-fuel ratio according to the detected values of the atmospheric pressure and the intake air temperature.

The burnt gas detecting means is a predetermined cylinder, for example, #
It is an oxygen concentration sensor (O2 sensor) provided in one cylinder. Feedback control of the fuel injection amount and the like is performed according to the detected oxygen concentration.

The knock detecting means 34 detects abnormal combustion in each cylinder, and when knocking occurs, ignition is shifted to the retard side or fuel is set to the rich side to eliminate knocking. Prevent engine damage.

The oil level detecting means is provided with level sensors in both the sub tank 67 in the cowling and the main tank 63 in the ship.

The thermoswitches, one provided on each of the left and right banks of the V-shaped bank, are composed of fast-responsive sensors such as a bimetal type temperature sensor, and detect a temperature rise of the engine due to an abnormality in the cooling system, etc. Perform misfire control to prevent it. The above-mentioned engine temperature detecting means is provided in the cylinder block and is used for correcting the control amount of the fuel injection. However, this thermoswitch is required to have a quick response in order to immediately cope with the temperature rise of the engine. .

The shift cut switch is for detecting the tension of the shift cable for switching the clutch and facilitating the switching of the dog clutch directly connected to the propeller.

The operating state detecting means is for detecting the operating state of the other outboard motor. The means is DES
A detection means is included. The DES detecting means detects the DES which is a signal for notifying when the other engine is in the misfire operation state due to an abnormality in the two-engine operation. That is, when the engine of one outboard motor is performing misfire control due to lack of oil, temperature rise, etc., the engine is one equipped with two outboard motors in parallel at the stern. DES is output from the DES output means, and is for detecting the DES and detecting the misfire operation state. By detecting this DES, the other engine is similarly subjected to misfire control so that the operating states of both engines are the same and the traveling balance is maintained.

The battery voltage detection means detects the battery voltage and corrects and controls the injection amount based on this voltage because the opening / closing speed of the valve changes and the discharge amount changes due to the change in the drive power supply voltage of the injector. Used for.

The starter switch detecting means is for detecting whether the engine is in the starting operation. If the engine is in the starting state, the fuel is made rich and the control for the starting operation is performed.

The two types of E / G stop switch detection means are an engine stop operation switch and a water drop detection switch. Among them, the water drop detection switch detects the water drop of an occupant and immediately starts the engine. Control to stop. These two types of E / G stop switch detecting means are shown as one E / G stop switch detecting means for convenience in the drawing.

Based on the input signals from the respective detecting means as described above, each control amount is calculated in the arithmetic processing unit, and based on the calculation result, the fuel injection means # 1 on the output side (right side in FIG. 4). To # 6, ignition means # 1 to # 6, a fuel pump and an oil pump are drive-controlled. It should be noted that the fuel injection means and the ignition means are an injector and an ignition plug, respectively, and are controlled in order independently for each cylinder.

In order to execute the calculation in such an arithmetic processing unit, as shown in the figure, the arithmetic processing unit has a nonvolatile memory such as a ROM storing a control program, a map and the like, and each detection signal and this. A volatile memory such as a RAM for storing temporary data for calculation based on

Next, the ignition timing control and fuel injection control of the outboard motor engine to which the present invention is applied will be described with reference to FIG. FIG. 5 is a block diagram showing a configuration for executing such a control flow. Each block is
It is incorporated as an arithmetic processing circuit in the arithmetic processing device shown in FIG.

The cylinder discriminating means 201 is a cylinder detecting means # 1.
To # 6 (FIG. 4), the cylinder number is determined based on the input signal from each cylinder. The cycle measuring means 1000 measures the time interval of the input signal from each cylinder based on the detection signal from this cylinder detecting means, and multiplies this by 6 to calculate the time (cycle) of one rotation. The engine rotation speed calculation means 203 calculates the reciprocal of this cycle to obtain the rotation speed. The throttle opening reading means 204 reads the opening with an analog voltage signal corresponding to the throttle opening.

The throttle opening signal from the throttle opening reading means 204 is A / D converted, and the rotation speed signal from the E / G rotation speed calculating means 203 and the start information from the starter switch are used as the basic ignition timing calculating means 210. And is sent to the basic fuel injection calculation means 211, and the ignition timing and the fuel injection amount of the reference cylinder # 1 are calculated using the three-dimensional map in each of the normal operation mode and the start mode. The engine speed signal and the throttle opening signal are further sent to the cylinder-by-cylinder ignition timing correction value calculating means 208 and the cylinder-by-cylinder fuel injection amount correction value calculating means 209, and the basic ignition timings for the remaining cylinders # 2 to # 6. And a correction value for the basic injection amount is calculated by map calculation for each cylinder.

On the other hand, trim angle reading means 205, engine temperature reading means 206 and atmospheric pressure reading means 2
Reference numeral 07 denotes a detection signal from each detection means (FIG. 4), which is sent to the ignition timing correction value calculation means 212 and the fuel injection amount correction coefficient calculation means 213, and the correction value and the correction coefficient according to each operating state. To calculate. In this case, regarding the ignition timing correction value, the number of angles of the correction advance angle (or the retard angle) to be added to the value of the basic ignition advance angle is obtained by a map stored in advance for each type of read data. As for the correction coefficient of the fuel injection amount, a value corresponding to the operating state is obtained from the map data stored in advance.

Although not shown in the drawings, the ignition timing correction and the fuel injection amount correction may be performed by further inputting the intake temperature detection data to the respective calculation means 212, 213 to perform the correction based on the intake temperature. The fuel injection amount correction value / correction coefficient calculation means 213 is normally operated from the start operation mode based on the start start information from the starter SW and the engine speed information or the temperature information from the E / G (engine) temperature detection means. Information on the elapsed time of the timer that starts from the time of shifting to the operation mode is also input. In the fuel injection amount correction value / correction coefficient calculation means 213, a correction coefficient by which the basic injection amount is multiplied and a correction value other than the cylinder-specific correction value,
That is, the post-starting correction value and the transitional correction value corresponding to the passage of time from the time when the starting operation mode is changed to the normal operation mode are calculated.

The calculation outputs of the ignition timing correction value calculation means 212 and the fuel injection amount correction value / correction coefficient calculation means 213 are:
It is inputted to the ignition timing correction means 214 and the fuel injection amount correction means 215, respectively, where the correction value is added to the basic ignition timing, the calculated value of the basic fuel injection is multiplied by the correction coefficient, and the post-starting correction value and the transient value are added. The time correction value is added to calculate the ignition timing of the # 1 cylinder and the control amount of the fuel injection.

The ignition timing and the fuel injection control amount of the reference cylinder # 1 are input to the cylinder-by-cylinder ignition timing correction means 216 and the cylinder-by-cylinder fuel injection amount correction means 217, where the corrected ignition timing for the # 1 cylinder is provided. And # 2 to # 6 by adding the control correction amount by the cylinder-by-cylinder ignition timing correction amount calculation means 208 and the cylinder-by-cylinder fuel injection amount correction value calculation means 209 to the # 2 and # 6 cylinders.
The ignition timings of the cylinders up to 6 and the control amount of the fuel injection amount are calculated.

Based on the ignition timing and the fuel injection control amount for each of the cylinders # 1 to # 6 calculated in this way, the ignition output means 218 determines the value of the angle of ignition advance for each cylinder. Set the calculated control amount with a timer,
The fuel output means 219 sets a crank angle corresponding to the valve opening time with a timer.

FIGS. 6 and 7 are flowcharts of the overall control of the respective engines of the two-engine outboard motor according to the embodiment of the present invention. This flowchart is a flow of a main routine showing a sequence program of the entire control process incorporated in the CPU of the control device (arithmetic processing device) of each engine.

When the main switch is turned on and the power is turned on to start the engine operation, each processing circuit in the control processing device is initialized after a predetermined reset time (step S11).

Next, at step S12, the operating state is judged and the result is held in the memory. Here, ON / OFF information of the main switch, ON / OFF of the starter SW read by using the starter SW detection means of FIG.
Information, and engine speed information calculated from the crank angle pulse train read from the crank angle detection means, a start determination for determining whether or not a starting state, throttle opening information read from the throttle opening detection means, engine speed information, Operating state information that is the operating state information of the other outboard motor that is read by the operating state detection means, or the following overheat, abnormal state information such as oil shortage,
Alternatively, the cylinder deactivation judgment as to whether or not the specific cylinder should be deactivated based on the rapid acceleration / deceleration information calculated from the time change of the throttle opening information, etc., mainly the feedback control of the oxygen concentration based on the throttle opening information and the engine speed information is performed. Whether or not to perform, mainly based on the same two pieces of information, whether or not to control and learn the control data in the case of a specific control condition, based on the engine speed information over-revolution determination of whether there is an excessive rotation, Overheat determination based on the throttle opening information, the engine speed information, and the temperature information by the engine (E / G) temperature detecting means or a thermo SW which is a more specific means, overheat determination, throttle opening information, engine Based on the number of revolutions information and the remaining oil amount information by the oil level detection means, the remaining oil Carry out the amount is less whether the oil empty judgment. In the case of an excessive rotation state, an overheat state and a state where the residual oil amount is small, misfire control is performed as described below. In step S12, further, a failure determination is made as to whether or not the throttle information, the crank angle information, and the O2 sensor information are missing or abnormal, or the pulsar information from the pulsar coil which is a kind of crank angle detecting means. Based on the failure information of the other, it is judged whether to control the passage, it is judged from the operating status information whether the two outboard motors are operating, and the other ship is judged from the cylinder deactivation status signal. From the three judgments, it is judged whether the outboard motor is in the cylinder deactivated operation state, and whether the other outboard motor is in the misfire control state that corresponds to the abnormality by DES (a signal that notifies the misfire control state that corresponds to the abnormality). The two-machine operating state determination, the rapid acceleration / deceleration determination as to whether the vehicle is in the rapid acceleration / deceleration state based on the time change of the throttle opening information, and the high speed rotation state are determined. Based on the ON / OFF information of the shift cut SW that operates during the shift operation, it is determined whether the shift cut is in the shift cut state.

Such a determination is made based on various information such as the detection information from the sensor read in the previous routine and the calculation result.

Next, in step S13, it is determined whether or not the routine work of loop 1 is performed. YE
If it is S, the process proceeds to step S14 and the switch information is read. Here, information from the E / G stop switch detecting means, the main switch, the starter switch detecting means, and the thermo SW is read. Then, in step S15, the information from the knock sensor (knock detection means) and the throttle sensor (throttle opening detection means) is read. After the information reading by the loop 1 is completed, the process proceeds to step S16, and it is determined whether or not the routine work of the loop 2 is performed.

The arithmetic processing unit sets the processing flag 1 of the loop 1 to 1 at intervals of 4 ms by hardware or software, and sets the processing flag 2 of the loop 2 at 1 at intervals of 8 ms.

FIG. 8 shows such loop 1 and loop 2
4 is a flowchart of a timer interrupt for executing the. Such a timer is set in the initialization step S11. While the routines of the loops 1 and 2 are being executed, the flag is set and the timer for the next routine is set.

Returning to FIG. 6, in step S13, the flag 1 is checked, and if it is 1, steps S14 and S15 are executed. Note that the flag 1 is cleared and becomes 0 at the same time when the process proceeds to step S14. When it is confirmed that the flag 1 is 0 in step S13, the process proceeds to step S16, and it is checked whether the flag 2 is 1. If the flag 2 is 1, the process proceeds to step S17 and the flag 2 is cleared to 0 at the same time. If the flag 2 is 0 in step S16, the process returns to step S12.

In step S17, the oil level is detected, and the shift cut switch which is activated in response to the tension of the shift cable which is large during the shift operation from the high rotation state and which is turned on when the tension is large is turned on and off.
The state is detected, and the two-engine running signal, the cylinder deactivation state signal, and the DES signal are detected. Further, in step S18, atmospheric pressure information, intake air temperature information, trim angle information, engine temperature information, battery voltage information, and oxygen concentration information in exhaust gas are atmospheric pressure detection means, intake air temperature detection means, trim angle detection means, E / G (engine) temperature detecting means, battery voltage detecting means, and O ₂ sensor. The A / F information before combustion is calculated based on the oxygen concentration information.

Next, in step S19, misfire control is performed. This is because, in the operation state determination in step S12 described above, the engine is in an abnormal state such as over-rotation, overheat at a predetermined throttle opening and engine speed, oil empty, or the other engine is in an abnormal state from the read information. The fuel control is performed so that the misfire of a specific cylinder is performed when the determination result that there is is present. Further, in the cylinder-by-cylinder correction in step S24 described below, misfire fuel control is executed to output to the memory that the misfire control state is in order to reduce the fuel injection amount of the cylinder in which misfire occurs compared to the other cylinders. Next, the fuel pump and the oil pump are drive-controlled based on the determination whether the engine is rotating and the information from the oil tank level sensor (step S20). For fuel, it drives the fuel pump if the engine is running, stops the fuel pump if the engine is stopped, and for oil it drives the pump when the oil tank in the cowl is low. The oil consumption is reduced by either replenishing the oil from the oil tank inside the ship or reducing the engine speed.

Next, in step S21, the cylinder deactivation determination result is determined. This is a determination step for selecting a map for arithmetic processing when it is determined in the above-described operating state determination step S12 that the cylinder deactivation operation is performed in the predetermined low load and low rotation state. If it is not the cylinder deactivation operation, the basic operation map of the normal all cylinder operation is used to perform the basic calculation of the ignition timing and the injection time and the correction calculation for each cylinder (step S22). It is also determined whether or not the engine is in the misfire control state, and when in the misfire control state, the injection time is supplied to the misfire cylinder so as to supply the same amount of fuel as the fuel injection amount to the other ignition cylinders or a fuel reduced by a predetermined ratio. Is set. As a result, the fuel is supplied even in the misfire control from the time when the throttle opening and the engine speed are equal to or higher than a predetermined value, so that the piston and the like can be cooled by the heat of vaporization and damage can be prevented. In the cylinder deactivated operation state, the ignition timing and the injection time are calculated and the correction calculation for each cylinder is performed using the cylinder deactivation map for the cylinder deactivated operation in which a specific cylinder is deactivated (step S24).

Next, in step S23 of FIG. 7, correction values for basic ignition timing and fuel injection are calculated according to operating conditions such as atmospheric pressure and trim angle. Subsequently, in step S25, a correction value associated with the feedback control of the oxygen concentration is calculated. At this time, the learning determination of the calculation information and the activation determination of the O2 sensor are performed. further,
In step S26, a correction value for the control amount is calculated based on the detection signal from the knock sensor to prevent engine seizure and the like.

Next, in step S27, the optimum ignition timing, injection time and injection timing are calculated by multiplying the basic ignition timing and the control amount of fuel injection by a correction coefficient and then adding a correction value or multiplying by the correction coefficient. Calculate After that, in step S290, the calculation of the engine pre-stop control is performed. This is a control for stopping the ignition and continuing the fuel injection for a predetermined time in consideration of restart when the engine is determined to be in the stopped state by turning off the main switch or the engine stop switch in step S12. It is a routine. With the above, the routine of the loop 2 is ended, and the process returns to the original operation state determination step S12.

FIG. 9 shows the flow of the TDC interrupt routine. A marker is fixed to the crankshaft, which causes each cylinder detecting means to output a signal notifying that the piston is at the top dead center in each cylinder when sequentially passing near each cylinder detecting means. The TDC interrupt is a routine interrupted by the main routine at any time based on the input of the TDC signal from each cylinder by the cylinder detecting means # 1 to # 6.

First, the number of the cylinder to which the signal is input is determined (step S28). Next, by comparing the cylinder number with the cylinder number of the previous input signal, it is determined whether the engine is rotating normally or reversely with respect to the rotation direction to be operated (step S29). If it is reversed, the engine is immediately stopped (step S33). If the engine is running in the normal direction, for example, the time interval between the cylinders # 1 and # 2 is counted and multiplied by 6 to calculate the cycle of engine rotation (step S30). Subsequently, the reciprocal of this cycle is calculated to calculate the rotation speed (step S31). When this rotation speed is lower than a predetermined rotation speed,
The engine is stopped (steps S32, 33). In addition,
A pulsar failure handling process is performed between step S28 and step S31.

Next, at step S34, it is judged if the input TDC interrupt signal is from a specific reference cylinder # 1. If the signal is from the reference cylinder # 1, it is determined whether or not the cylinder deactivation operation is being performed (step S3).
5) If the cylinder deactivation operation is in progress, it is determined whether or not the pattern of cylinders to be deactivated should be changed (step S37),
The pattern is switched (step S38) or the process proceeds to step S39 as it is without switching, and the cylinder deactivation operation information by ignition control is set. When the interrupt signal is not from # 1 (step S34) or when the cylinder deactivation operation is not in progress (step S35), the cylinder deactivation information is left as it is or the cylinder deactivation information is cleared (step S36) and the process proceeds to step S39 to deactivate the cylinder by ignition control. Set the driving information. The ignition pulse of the cylinder to be ignited is set based on this ignition cut-off cylinder information (step S40).

The details of this ignition pulse set are shown in FIG. The ignition timing obtained by the calculation is converted into the crank angle 60 degrees before TDC, that is, how many times it becomes a reference in the V-type 6-cylinder engine, and divided by 0.8 to be rounded to the pulse number. T of the cylinder that becomes TDC 60 degrees before
When the DC signal is input, the data of the rounded pulse number is held in the timer that constitutes the ignition output means 218, and at the same time, the number of pulses that is held each time the pulse from the crank angle detecting means reaches the timer. When the number of held pulses becomes 0, the ignition output means 218
Sparks the spark plug 19.

This embodiment is intended for a 6-cylinder V-type 2-bank engine, for example, and has odd numbered cylinders (# 1,
3, 5) are arranged in the left bank and even-numbered cylinders (# 2,
4 and 6) are arranged in the right bank. A separate timer is provided for each bank in order to control these cylinders for each bank. When setting the number of crank angle pulses corresponding to the ignition timing in these timers, as shown in the figure, first determine whether the cylinder number is an even number or an odd number, and depending on whether it is an even number or an odd number, set the ignition timing data to the corresponding bank. (In the figure, the odd bank is timer 3 and the even bank is timer 4), and the ignition cylinder number is set.

After that, with respect to the deactivated cylinder that causes the misfire in the ignition control, the cylinder that reduces the fuel injection amount in the fuel injection control is set as the cylinder deactivation information due to the fuel injection control (step S41 in FIG. 9), and the misfire deactivated in the ignition control. The injection time corresponding to the fuel injection amount reduced from the fuel injection control amount calculated for each cylinder, and the injection time corresponding to the fuel injection control amount calculated for the other cylinders, for each cylinder. The pulse is set (step S42).

When measuring the above-mentioned engine cycle, if there is an input signal (TDC signal) from one cylinder, the TDC interrupt shown in FIG.
The period measurement timer starts counting the number of constant frequency pulses at the time of inputting the TDC signal, and the TD of the next cylinder
When the C signal is input, it is reset and the counting of the next cylinder is started. In this case, when the count value exceeds a predetermined value, an overflow occurs and the count is reset. The timer overflow interrupt is executed at the time when this overflow occurs, that is, when it is detected that the cycle of the crank angle of 60 degrees is the low speed rotation for a predetermined time or longer.

FIG. 11 shows this overflow interrupt. When an overflow occurs, the number of times is first stored and it is determined whether the engine is in the starting operation state. If the operating mode is the starting state, the engine rotation is low due to the overflow, and the operation is continued.
If it is not in the start mode, it is determined whether or not the TDC signal pulse has been missed, that is, the TDC signal pulse has not been transmitted due to some trouble, and whether the overflow is detected by normal signal transmission without pulse omission. If the engine is running at low speed, stop the engine. If there is a missing pulse, it is determined whether or not the overflow detection is the second time, and if it is the second time, the engine is stopped because the rotation speed is too low. As a result, the engine is always stopped when there is an abnormality in the signal transmission system at low speed.

FIG. 12 shows an interrupt routine of the timers 3 and 4 corresponding to each bank for setting the ignition timing of each cylinder. When an engine rotation signal (TDC signal) is input from each cylinder, the timers 3 and 4 are interrupted. First, the cylinder deactivation information indicating whether the engine is in the cylinder deactivation operation for a predetermined low rotation speed or less and the misfire information indicating whether the ignition is misfired by detecting overheat or overrevolution (overspeed) are read. After this, a timer value corresponding to the ignition timing is set in the timer 3 or 4 corresponding to the cylinder number. After that, when the misfire is caused by the cylinder deactivation information or the misfire information, the ignition processing routine is not performed, so that the spark plug is not discharged even at the timing set by the timer, and the phase is delayed by 120 °. The ignition timing of the cylinder is read from the memory, the timing is set in the timer, and the process directly returns to the main flow. When not causing misfire, the number of the cylinder to be ignited is read, and a pulse (HI) is output from the ignition output port of the ignition drive circuit of the cylinder at the timing set by the timer to discharge the spark plug. The ignition time corresponds to the pulse width and is set by a timer, or a loop that requires a predetermined number of times for execution is executed to obtain the required pulse width. After the elapse of this predetermined ignition time, the signal from the ignition output port is changed to LO.
Then, the discharge of the spark plug is completed. Further, if the ignition drive circuit is LOW active, the logic is the reverse of the above.

The above is the mechanical structure of the outboard motor engine to which the present invention is applied, the system structure of the entire control system, and the flow of its operation.

FIG. 13 is a time chart of the reverse rotation prevention control according to the present invention. This reverse rotation prevention control is performed by the above-mentioned FIG.
It is performed in the TDC interrupt routine shown in FIG. That is, when the starter motor (not shown) is activated and the crankshaft is in the cranking state, the control device starts the control by the main routine shown in FIG. And step S
It is determined in step 12 that the engine is starting, and step S
At 22, the ignition timing correction and the fuel injection amount correction for improving the startability are further performed. As a result, an initial explosion occurs in the combustion chamber early after the starter motor is started. Along with cranking, the TDC signal (pulser signal) is sequentially input to the control device from the start up to the first explosion, and not only the following reverse rotation determination but also ignition and injection based on the TDC signal are performed in each cylinder. Even after the first explosion, as shown in the flowchart of FIG. 9, the input cylinder number of the pulsar signal is determined by the TDC signal (pulsar signal) (step S28), and then it is determined whether the engine is in reverse rotation (step S29). If it is a reverse rotation, the cycle is measured (step S30), and if it is a reverse rotation, engine stop processing is performed (step S33). The time chart of this flow is shown in FIG. That is, when the pulsar signals (engine rotation signals) of the cylinders # 1 to # 6 are input, the timers 3 and 4 are set (countdown starts) according to the even numbered cylinders and the odd numbered cylinders for the ignition timing, and the count is zero. Then, the ignition pulse of the next cylinder is output. As for fuel injection, fuel injection into the cylinder of the pulsar signal is performed in synchronization with each pulsar signal. In the present invention, the cylinder number is determined by the input of the pulser signal of each cylinder (step S28 in FIG. 9), and the reverse rotation determination is performed based on this cylinder number as described later, and then the pulser signal between the previous time and this time is determined. Is measured (step S30 in FIG. 9), and the engine speed is calculated based on this (FIG. 9).
Step S31).

FIG. 14 is a detailed diagram of a pulsar signal according to the embodiment of the present invention. As shown, each cylinder # 1- #
Independently for each 6, the independent pulser signals are sequentially input to the input port of the control circuit (CPU) with a phase difference of 60 degrees.
Further, a pulser combined signal obtained by combining these pulser signals for each cylinder is created in synchronization with an independent pulser signal and is input to the input capture of the CPU. TDC
The interrupt is generated by this composite signal.

At the TDC interrupt, by reading the state of the input port of the CPU, it is possible to determine which cylinder the pulsar signal currently input is. For example, if the independent pulsar signal is L active, the state of each input port is detected in the TDC interrupt by the combined signal and L
The cylinder of the port in the OW state is the current cylinder. When the current cylinder number is determined in this way, the forward / reverse rotation can be determined by comparing with the previous cylinder number based on this.

FIG. 15 is a detailed flowchart of the cylinder discriminating step S28 and the reverse rotation discriminating step S29 in the above TDC interruption. As mentioned above, first the CPU
Read the input port status of (step S1901),
The cylinder number is determined and the previous cylinder number is updated (step S1902). Subsequently, it is determined in order from # 1 whether the TDC signal input this time is # 1 to # 6 (steps S1903 to S1908), and when the corresponding cylinder is reached, the cylinder number (steps S1909 to S19) is reached.
14) and the previous cylinder number are compared (step S19).
15). That is, it is determined whether the current number is larger than the previous and current cylinder numbers. If this number is large, it is determined to be forward rotation, and if it is small, it is determined to be reverse rotation. However, when the cylinder number is # 1, the opposite is true. That is, step S19
If the current cylinder number is # 1 even if the reverse rotation is performed in 15, the change from # 6 to # 1 is the normal rotation, and the rotation is returned to the normal rotation determination side (step S1916). Although not shown, such determination as to whether or not the cylinder is the # 1 cylinder is naturally performed when it is determined to be normal rotation in step S1915, and in the case of the # 1 cylinder, the determination is returned to the reverse rotation determination side.

In this way, forward / reverse rotation is discriminated, and if it is normal rotation, the cycle is measured as described above (step S30 in FIG. 9), and if it is reverse rotation, engine stop processing is performed (step FIG. 9). S33). Regarding the stop processing, the output is immediately stopped at the same time when the reverse rotation is detected for at least the ignition of the fuel injection and the ignition. Regarding fuel injection, injection is continued in order to improve startability at the time of restart. In this case, the ignition output at restart is not allowed until the engine is completely stopped. This is because the reverse rotation due to inertia is completely stopped and then restarted.

[0080]

As described above, in the present invention, the combustion is stopped after the reverse rotation is detected by the misfire at the spark plug, while the fuel injection is continued until the inertia energy is consumed and the engine is stopped. Thus, by allowing the fuel to remain between the fuel injection point and the combustion chamber, the restartability after the engine is stopped can be improved. Further, the reverse rotation of the engine can be reliably detected and the engine can be stopped with a simple configuration by the software by program assembly without using a special hardware circuit during cranking. In addition, reverse rotation can be detected if there are two pulser signals after engine cranking has started. For example, in the case of a 6-cylinder engine, the pulsar signal interval is 60 degrees, and therefore the reverse rotation can be detected by 120 degrees of crankshaft rotation.
In this way, the forward and reverse rotations can be detected in a short time, so the startability can be improved.

[Brief description of drawings]

FIG. 1 is an external view of a two-engine outboard motor to which the present invention is applied.

FIG. 2 is a configuration diagram including a fuel system of the outboard motor of the present invention.

FIG. 3 is a structural explanatory view of a throttle lever of an outboard motor to which the present invention is applied.

FIG. 4 is a structural explanatory diagram of a drive control system of a two-engine outboard motor.

5 is a control block diagram of the control system of FIG.

FIG. 6 is a flowchart of a main routine in a control sequence of an internal combustion engine to which the present invention is applied.

FIG. 7 is a continuation of the flowchart of FIG.

8 is a flowchart of a timer interrupt routine in the flowchart of FIG.

9 is a flowchart of a TDC interrupt routine in the flowchart of FIG.

FIG. 10 is a flowchart of an ignition pulse setting routine.

FIG. 11 is a flowchart of a timer overflow interrupt routine.

FIG. 12 is a flowchart of a timer interrupt routine for each bank.

FIG. 13 is a time chart of reverse rotation prevention control according to the embodiment of the present invention.

FIG. 14 is a time chart of a pulser signal according to the embodiment of the present invention.

FIG. 15 is a detailed flowchart of reverse rotation prevention control according to the embodiment of the present invention.

FIG. 16 is an explanatory diagram of reverse rotation prevention control by a mask circuit.

[Explanation of Codes] 201: Cylinder discrimination means, 203: Engine speed calculation means, 205: Trim angle reading means, 210: Basic ignition timing calculation means, 211: Basic fuel injection amount calculation means, 2
14: Ignition timing correction means, 215: Fuel injection amount correction means, 218: Ignition output means, 219: Fuel output means.

Claims (3)

[Claims] 1. Fresh air is supplied to a combustion chamber through an intake passage, a crank chamber, and a scavenging passage, an injector for fuel injection is arranged upstream of the combustion chamber, and a spark plug is arranged in the combustion chamber. In a two-cycle fuel injection type internal combustion engine in which fuel is injected at an ignition timing corresponding to the operating state based on the engine, the engine reverse rotation detecting means is arranged, and when reverse rotation is detected, ignition is stopped. On the other hand, a method for preventing reverse rotation of a two-cycle fuel injection type internal combustion engine in which fuel injection is continued. 2. In each of a plurality of cylinders, fresh air is supplied to a combustion chamber through an intake passage, a crank chamber and a scavenging passage,
An injector for fuel injection upstream from the combustion chamber,
An ignition plug is arranged in the combustion chamber, and the ignition plug of each cylinder is ignited at an ignition timing corresponding to the operating state based on at least one of the cylinder detection signals corresponding to each cylinder, and fuel is injected from the injector of each cylinder. A control device for controlling injection is arranged, and a cylinder detection signal is sequentially input to the control device for each cylinder at a predetermined crank angle according to the engine rotation, and the cylinder of the input cylinder detection signal is input. The engine rotation direction is determined by comparing the number with the cylinder number of the previously input cylinder detection signal, and if the engine rotation is reversed, ignition is stopped in a predetermined number of cylinders or more while fuel injection continues. A method for preventing reverse rotation of a two-cycle fuel injection type internal combustion engine. 3. Various operating state detecting means, ignition means,
A fuel injection means and a control device for calculating an ignition timing and a fuel injection amount according to an operating state in accordance with a predetermined program are provided, and the control device controls each cylinder for each predetermined crank angle as the engine rotates. Correspondingly input the cylinder detection signals in order, the control device determines the engine rotation direction by comparing the cylinder number of the input cylinder detection signal and the cylinder number of the previously input cylinder detection signal, A reverse rotation preventing device for a two-cycle fuel injection internal combustion engine, wherein ignition is stopped in a predetermined number of cylinders or more while reverse rotation is performed, while fuel injection is continued.