JP2004211621A - Method and device for rotation direction reverse control of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotation direction reverse control method for an internal combustion engine for performing reverse control of the rotation direction of a two-cycle internal combustion engine, having a strong probability of success in reverse of the rotation direction. <P>SOLUTION: When a rotation direction change switch 8 is operated to reverse the rotation direction of the engine, the engine is ignited at an over advance position after ignition operation of an ignition device 3 is stopped to decelerate the engine. If it is determined that the rotation direction of the internal combustion engine has not been reversed after the ignition at the over advance position, a process for performing ignition at the over advance position while a rotation speed of the internal combustion engine is lowered, and a process for determining the rotation direction are repeated at least once. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rotation direction reversal control method for an internal combustion engine that performs control for reversing the rotation direction of a two-cycle internal combustion engine, and to a rotation direction reversal control device for an internal combustion engine used for performing the method.
[0002]
[Prior art]
2. Description of the Related Art In vehicles, such as scooters, snowmobiles, and buggy cars, where importance is placed on simplicity, a small two-stroke internal combustion engine is used as a drive source, and a power transmission device that transmits the output of the internal combustion engine to drive wheels. As such, a continuously variable transmission such as a centrifugal clutch type is widely used. This type of vehicle emphasizes that it is small, lightweight, inexpensive, and easy to operate. Therefore, a continuously variable transmission that does not incorporate a back (reverse) gear is often used.
[0003]
As described above, vehicles using transmissions without reverse gear cannot reverse, so when it is necessary to reverse the running direction in a narrow place, lift the entire vehicle body, etc. It was necessary to change the direction, and the operability was poor.
[0004]
Therefore, as shown in Patent Document 1, by focusing on the feature of a two-cycle internal combustion engine that can be rotated in both forward and reverse directions, by switching the rotation direction of the internal combustion engine when necessary, There has been proposed a rotation direction reversal control device that switches the running direction.
[0005]
A reversal control device disclosed in Patent Document 1 is configured to reverse a rotation direction of an internal combustion engine by operating a rotation direction switch that is operated when the rotation direction switch is operated. Rotation direction inversion control means for performing the process, and inversion ignition control means for igniting the internal combustion engine at an ignition position in a state where the rotation direction is inverted when it is confirmed that the rotation direction of the internal combustion engine has been inverted. The rotation direction reversal control means includes a deceleration process for lowering the rotation speed by causing the internal combustion engine to misfire, and an over-advancing angle of the internal combustion engine in a state in which the rotation speed is reduced below a set value by the deceleration process A reversal control comprising an over-advance angle control process of igniting at the set ignition position and a rotation direction determination process of determining whether the rotation direction of the internal combustion engine has been reversed by the ignition at the over-advanced ignition position. Configured Migihitsuji.
[0006]
In the rotation direction reversal control device disclosed in Patent Document 1, when a command to reverse the rotation direction of the two-stroke internal combustion engine is given, the operation of the ignition device is first stopped to cause the engine to misfire and the rotation speed to be increased. Lower. Next, when the rotational speed of the engine is sufficiently reduced and the inertia of the piston is reduced, the ignition position of the engine (the crank angle position when the engine is ignited) is changed to the over-advanced position (the appropriate ignition position during steady operation). (A position further advanced than the maximum advance position).
[0007]
If the engine is ignited at the over-advanced position with the engine inertia reduced in this way, the explosive force generated by the ignition will overcome the engine inertia and push back the piston moving toward top dead center, The direction of rotation of the engine is reversed. After it is confirmed that the rotation direction of the engine has been reversed, if the engine is ignited at an appropriate ignition position in the rotation direction, the engine can be operated with the rotation direction reversed.
[0008]
Also, in Patent Document 2, the applicant discloses in the reversal control based on the output of one signal generator that generates a pulse signal at a specific crank angle position of an internal combustion engine and the output waveform of a magnet generator driven by the internal combustion engine. We have proposed a rotation direction reversal control device that can easily determine the rotation direction of the engine.
[0009]
[Patent Document 1]
U.S. Pat. No. 5,036,802 and drawings
[0010]
[Patent Document 2]
JP 2001-304034 A
[0011]
[Problems to be solved by the invention]
As described above, when the rotational direction of the engine is reversed by igniting the engine at the over-advanced ignition position with the engine rotational speed reduced, the ignition at the over-advanced position must be performed. The reversal of the rotation direction is not always successful. Depending on the state of combustion in the cylinder caused by ignition at the over-advanced position, reversal of the rotation direction may fail.
[0012]
In order to improve the operability when reversing a vehicle or the like, it is desirable to increase the probability of succeeding in reversal of the rotation direction as much as possible. No particular effort has been made to increase the probability that the rotation direction will be increased. If the ignition in the over-advanced position is performed once when the rotation direction switch is operated and the reversal of the rotation direction fails, the rotation speed To request the operation of the rotation direction switch again or stop the engine.
[0013]
In particular, in the case of a multi-cylinder internal combustion engine provided with two or more cylinders, the combustion state and the air-fuel ratio may be different for each cylinder. When ignition is performed at the over-advanced position, the rotation direction is successfully reversed, but ignition is performed at the over-advanced position in a cylinder in a combustion state that is not compatible with the reversal of the rotation direction. , The probability of failing to reverse the rotation direction increases.
[0014]
An object of the present invention is to provide a rotation direction reversal control method for an internal combustion engine capable of increasing the probability of succeeding in reversing the rotation direction of the engine as compared with the related art, and a reversal control device used for performing the method. To provide.
[0015]
[Means for Solving the Problems]
The present invention relates to a deceleration process for reducing the rotation speed of an internal combustion engine when a command to reverse the rotation direction of a two-cycle internal combustion engine is given, and an internal combustion engine in a state where the rotation speed is reduced to less than a set value by the deceleration process. Performing an over-advanced ignition process of igniting the engine at an over-advanced ignition position and a rotation direction determining process of determining whether the rotation direction of the internal combustion engine has been reversed by ignition at the over-advanced ignition position, When it is determined in the rotation direction determination process that the rotation direction of the internal combustion engine is reversed, the internal combustion engine is ignited at an ignition position suitable for operating the internal combustion engine with the rotation direction reversed, and the rotation direction is reversed. The present invention is directed to an internal combustion engine rotation direction reversal control method for operating an internal combustion engine in a state.
[0016]
In the present invention, after performing the over-advanced ignition process once, when it is determined in the rotation direction determination process that the rotation direction of the internal combustion engine is not reversed, the rotation speed of the internal combustion engine is reduced to less than a set value. The over-advanced ignition process and the rotation direction determination process are repeated at least once in the state of being held.
[0017]
As described above, when it is determined that the rotation direction of the internal combustion engine is not reversed in the rotation direction determination process as a result of performing the over-advance angle ignition process, the over-advance angle ignition process and the rotation direction determination process are repeated. By doing so, the chances of reversing the rotation direction can be increased, so that the probability of successful reversal of the rotation direction can be increased, and the operability when the vehicle or the like moves backward can be improved.
[0018]
The reversal control device for performing the above method includes a rotation direction changeover switch operated when reversing the rotation direction of the two-cycle internal combustion engine, and a deceleration process for decelerating the internal combustion engine when the rotation direction changeover switch is operated. Over-advanced ignition means for performing an over-advanced ignition process of igniting the internal combustion engine at an over-advanced ignition position in a state where the rotation speed of the internal combustion engine is reduced below a set value by the deceleration control means A rotation direction determining means for performing a rotation direction determination step of determining whether or not the rotation direction of the internal combustion engine has been reversed by the ignition at the over-advanced ignition position; and the rotation direction of the internal combustion engine is reversed by the rotation direction determination means. And a reversal point ignition control means for igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine with the rotation direction reversed when it is determined that the rotation has been performed.
[0019]
In the case where the present invention is applied to such a control device, in addition to the above-described configuration, an over-advanced ignition process by the over-advanced ignition device in a state where the rotation speed of the internal combustion engine is reduced to less than a set value. An over-advanced ignition repetition control means is provided for repeating the rotation direction determination process by the rotation direction determination means up to n times (n is a set value consisting of an integer of 2 or more) until the rotation direction of the internal combustion engine is reversed.
[0020]
In a preferred aspect of the present invention, as described above, even if the over-advance angle ignition process and the rotation direction determination process are performed a set number of times in a state where the rotation speed of the internal combustion engine has been reduced to less than the set value, the internal When it is not determined that the rotation direction of the internal combustion engine has been reversed, the speed increasing step of increasing the rotation speed of the internal combustion engine to a predetermined speed, the deceleration step, the over-advance angle ignition step, and the rotation direction determination step And a step of repeating the over-advanced ignition step and the rotation direction determination step when the rotation direction has not been reversed. At least one inversion control step is performed. The processing for stopping the internal combustion engine is performed when is not reversed.
[0021]
In the case where the present invention is applied to the rotation direction reversal control method for a two-cycle multi-cylinder internal combustion engine, after performing an over-advanced ignition process for one cylinder of the internal combustion engine, the rotation direction determination process determines the rotation direction of the internal combustion engine. When it is determined that the rotation direction has not been reversed, while the rotation speed of the internal combustion engine is kept lower than the set value, the over-advance angle ignition process and the rotation of the other cylinders are continued. The direction determination process is performed.
[0022]
A rotation direction reversal control device used for performing a rotation direction reversal control method for a two-cycle multi-cylinder internal combustion engine includes a rotation direction changeover switch operated when reversing the rotation direction of the engine and a rotation direction changeover switch operated by the rotation direction changeover switch. Deceleration control means for performing a deceleration process of decelerating the engine when the engine is depressed, and an over-advance angle for igniting the engine at an ignition position where the engine is over-advanced in a state where the rotation speed of the engine is reduced below a set value by the deceleration control means Over-advance angle ignition means for performing an ignition process, rotation direction determination means for performing a rotation direction determination step for determining whether the rotation direction of the internal combustion engine has been reversed by ignition at the over-advanced ignition position, and rotation direction determination A reversal point ignition control means for igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine in a state where the rotation direction is reversed when it is determined that the rotation direction of the internal combustion engine is reversed by the means. Further, when the over-advanced ignition process by the over-advanced ignition device is performed on one cylinder of the internal combustion engine, the result is that the rotation direction determination device determines that the rotation direction of the internal combustion engine is not reversed. In this case, it is possible to provide an over-advanced ignition repetition control unit for repeating the over-advanced ignition process by the over-advanced ignition unit and the rotation direction determination process by the rotation direction determination unit for the other cylinders.
[0023]
As described above, if ignition of one cylinder at the over-advanced position fails as a result of reversal of the rotational direction, ignition of the other cylinder at the over-advanced position is performed. Then, even if there is a difference in the combustion state between the cylinders, the probability of succeeding in reversing the rotation direction can be increased.
[0024]
When the present invention is applied to a two-cycle multi-cylinder internal combustion engine, the over-advance ignition process and the rotation direction determination process are performed for all cylinders in a state where the rotation speed of the internal combustion engine is reduced below a set value. Even when it is not determined in the rotation direction determination process that the rotation direction of the internal combustion engine has been reversed, the speed increasing process, the deceleration process, and the over-advance angle ignition process for increasing the rotation speed of the internal combustion engine to a predetermined speed are performed. And performing at least one reversal control step including a rotation direction determination step and a step of repeating the over-advance angle ignition step and the rotation direction determination step when the rotation direction is not reversed, and setting the reversal control step. It is preferable to stop the internal combustion engine when the rotation direction has not been reversed even after the number of repetitions performed.
[0025]
With this configuration, the chances of reversing the rotation direction can be increased, and the probability of successful reversal of the rotation direction can be increased. In addition, since the engine can be stopped when the engine is hard to reverse, it is possible to prevent the reversal control from being repeated for an abnormally long time.
[0026]
The determination of the rotation direction of the internal combustion engine can be performed by a method similar to the method used in the control device previously proposed by the present applicant in Japanese Patent Application Laid-Open No. 2001-304034 (Patent Document 2). The control device proposed in Japanese Patent Application Laid-Open No. 2001-304034 is configured to generate an AC output voltage of 2n cycles (n is an integer of 1 or more) per one revolution of the internal combustion engine. An AC magnet generator in which the phase of the AC output voltage is set so that the cross point coincides with the low-speed ignition position at the time of reverse rotation of the internal combustion engine, a pulse signal of one polarity and the other in synchronization with the rotation of the internal combustion engine The pulse signal of one polarity and the pulse signal of the other polarity are respectively generated during the forward rotation of the internal combustion engine and the low-speed ignition position and the low speed during the forward rotation of the internal combustion engine. A magnet that is generated at a position advanced from the ignition position and that generates a pulse signal of a half-wave of the AC output voltage of the magnet generator when a pulse signal of one polarity is generated and a pulse signal of the other polarity is generated Departure A signal generator in which the generation position of each pulse signal is set so that the polarity of the half-wave of the AC output voltage of the machine is the same, and the output of the magnet-type AC generator and the output pulse of the signal generator are provided. Is determined from the relationship.
[0027]
That is, when the magnet generator and the signal generator are provided as described above, the magnets when the signal generator generates each pulse signal when the engine is rotating forward and when the engine is rotating reversely are provided. Since the polarity of the half-wave of the output voltage of the generator is different, the rotation direction of the engine is determined by observing the polarity of the half-wave of the output voltage of the magnet generator when the signal generator generates each pulse signal. be able to.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a hardware configuration of one embodiment of a rotation direction reversal control device for an internal combustion engine according to the present invention. The hardware configuration itself was disclosed by the applicant in Japanese Patent Application Laid-Open No. 2001-304034. It is similar to the one proposed.
[0029]
In FIG. 1, 1 is an AC magnet generator attached to a two-stroke internal combustion engine (not shown) for driving a vehicle such as a snowmobile, 2 is a signal generator that generates a pulse signal at a specific crank angle position of the internal combustion engine, 3 is An ignition device 5 for igniting the internal combustion engine is a microcomputer for controlling the ignition device 3. In this example, it is assumed that the two-cycle internal combustion engine has two cylinders.
[0030]
The magnet generator 1 generates power using a multi-pole flywheel magnet rotor attached to a rotating shaft (usually a crankshaft) of an engine and an armature core having a multi-pole magnetic pole portion facing the magnetic pole of the rotor. It is a well-known type including a stator wound with coils, and the stator is fixed to a mounting portion provided in an engine case or the like. In the magnet generator 1, in addition to the exciter coil EX, which is a power generation coil for applying ignition energy to the ignition device 3, a power generation coil for driving a lamp load and the like and a power generation coil for charging a battery (both not shown). Is provided. This magnet generator is configured such that a generator coil provided on the stator side generates 2n (n is an integer of 1 or more) cycles of AC voltage during one rotation of the rotating shaft of the engine. In the illustrated magnet generator, the rotor and the stator are configured to have 12 poles, and the exciter coil EX is used for one rotation of the rotating shaft of the engine as shown in FIGS. 2 (A) and 2 (C). To generate an AC output voltage Ve of six cycles. 2 represents the rotation angle of the rotation shaft of the engine. FIG. 2A shows an output voltage waveform of the exciter coil when the engine is rotating forward, and FIG. 2C shows an output voltage waveform of the exciter coil when the engine is rotating reversely. . As is apparent from these figures, when the rotation direction of the engine is reversed, the phase of the output voltage of the exciter coil is reversed. Since the magnet generator has 12 poles, the rotation angle (mechanical angle) corresponding to each half-wave period of the output voltage of the exciter coil is 30 degrees.
[0031]
In this specification, the rotation direction of the engine when the vehicle is moved forward is defined as forward rotation, and the rotation direction of the engine when the vehicle is moved backward is defined as reverse rotation.
[0032]
The signal generator 2 is a well-known type that generates a pulse signal by detecting a reluctor (an inductor magnetic pole portion composed of a protrusion or a concave portion) formed on a rotor provided to rotate synchronously with the engine. Or the like and opposed to the rotor.
[0033]
This type of signal generator is provided with an iron core having a magnetic pole portion at a tip facing a reluctor, a signal coil SG wound around the iron core, and a permanent magnet magnetically coupled to the iron core. A pulse signal having a different polarity is induced in the signal coil SG due to a change in magnetic flux generated when the portion starts facing the reluctor provided on the rotor and when the facing ends. The rotor provided with the reluctor is often configured using a flywheel that forms the yoke of the rotor of the magnet generator, but may be provided separately from the flywheel.
[0034]
The signal generator 2 obtains a pulse signal for determining an ignition position at a low speed of the engine (a crank angle position corresponding to an ignition timing) and a pulse signal for determining a timing for starting measurement of the ignition position of the engine. It is provided for. In the illustrated example, the internal combustion engine has two cylinders, a pulse signal for determining the ignition position of the engine at low speed for each cylinder, and a pulse signal for determining the timing for starting the measurement of the ignition position. In order to require a pulse signal, the rotor of the signal generator 2 is provided with two reluctors at 180-degree intervals.
[0035]
FIG. 2B shows a pulse signal generated by the signal generator 2 when the engine is rotating forward, and FIG. 2D shows a signal generated by the signal generator 2 when the engine is rotating reversely. FIG. In FIG. 2, θ10 and θ20 are the top dead center positions of the pistons of the first and second cylinders of the engine (the crank angle positions where the pistons correspond to the top dead center), respectively.
[0036]
When the engine is rotating forward, as shown in FIG. 2B, the signal generator 2 is slightly smaller than the top dead center position θ10 of the first cylinder of the engine (in this example, the mechanical angle is 5 °). ) The ignition position at low speed of the first cylinder at the time of forward rotation set at the advanced position (this ignition position is called a hardware ignition position in the sense of an ignition position determined by hardware). A (one polarity) pulse signal Vsa1 is generated, and a negative polarity (the other polarity) pulse signal Vsb2 is generated at a crank angle position θ12 which is sufficiently advanced from the hard ignition position θ11 during the forward rotation. In this example, the angle width (arc angle) of the reactor detected by the signal generator 2 is set to 60 °. Therefore, the angle between the hard ignition position θ11 for the first cylinder and the crank angle position θ12 is equal to 60 °. Here, the crank angle position θ12 is obtained by measuring the ignition position of the first cylinder (calculated by software) calculated by the microcomputer (the ignition position determined by software is called a soft ignition position). It is used as the first cylinder soft ignition reference position to be started.
[0037]
When the engine is rotating forward, the signal generator 2 is slightly smaller than the top dead center position θ20 of the second cylinder of the engine (in the mechanical angle in this example, as shown in FIG. 2B). 5 °) A pulse signal Vsa2 of positive polarity (one polarity) is generated at the hard ignition position θ21 which is the ignition position at low speed of the second cylinder at the time of forward rotation set to the advanced position, and the forward rotation is performed. A pulse signal Vsb2 having a negative polarity (the other polarity) is generated at a crank angle position θ22 which is sufficiently advanced from the hard ignition position θ21 at the time. The crank angle position θ22 is used as a second cylinder soft ignition reference position at which measurement of the second cylinder soft ignition position calculated by the microcomputer is started.
[0038]
When the engine is rotating in the reverse direction, the signal generator 2 is slightly smaller than the top dead center position θ10 of the first cylinder of the engine (5 in mechanical angle in this example) as shown in FIG. °) A pulse signal Vsb1 'having a negative polarity (the other polarity) is generated at a retarded crank angle position θ11, and a positive polarity (one polarity) is generated at a crank angle position θ12 further delayed from the crank angle position θ11. ) Is generated.
[0039]
When the engine is rotating in the reverse direction, the signal generator 2 is slightly smaller than the top dead center position θ20 of the second cylinder of the engine (5 in mechanical angle in this example) as shown in FIG. °) A pulse signal Vsb2 ′ of negative polarity (the other polarity) is generated at the retarded crank angle position θ21, and a positive polarity (one polarity) is generated at the crank angle position θ22 further delayed from the crank angle position θ21. ) Is generated.
[0040]
In the present embodiment, the crank angle position θ22 at which the pulse signal Vsa2 ′ is generated and the crank angle position θ12 at which the pulse signal Vsa1 ′ are generated at the time of reverse rotation of the engine are used to start measuring the ignition timing of the first cylinder of the engine. It is used as a reference position and a reference position for starting measurement of the ignition timing of the second cylinder.
[0041]
In the illustrated example, the polarity of the half-wave of the AC output voltage Ve of the magnet generator 1 when the pulse signal of one polarity is generated regardless of whether the engine is rotating forward or reverse. And the generation position of the pulse signal is set such that the polarity of the half-wave of the AC output voltage of the magnet generator when the pulse signal of the other polarity is generated is the same. In the illustrated example, the magnet generator 1 generates a positive half-wave voltage when the signal generator 2 generates the positive pulse signals Vsa1 and Vsa2 and the negative pulse signals Vsb1 and Vsb2 during the forward rotation, respectively. When the signal generator 2 generates the positive polarity pulse signals Vsa1 'and Vsa2' and the negative polarity pulse signals Vsb1 'and Vsb2' when the signal generator 2 rotates in the reverse direction, the magnet generator 1 generates a negative half-wave voltage. As described above, the phase relationship between the output of the signal generator 2 and the output of the magnet generator 1 is set.
[0042]
Therefore, the polarity of the half-wave of the output voltage of the magnet generator 1 when the signal generator generates the positive pulse signals Vsa1, Vsa2 or Vsa1 ', Vsa2, or the negative pulse signals Vsb1, Vsb2 Alternatively, the rotational direction of the engine can be determined by looking at the half-wave polarity of the output voltage of the magnet generator when Vsb1 ′ and Vsb2 ′ are generated. In the present embodiment, the rotation direction of the engine is determined using the relationship between the output pulse of the signal generator 2 and the output voltage of the magnet generator 1, as described above.
[0043]
In the present embodiment, the AC output voltage Ve of the magnet generator 1 is adjusted so that any zero cross point of the AC output voltage Ve coincides with the low-speed ignition position (hard ignition position) at the time of reverse rotation of the internal combustion engine. Is set. In the illustrated example, as shown in FIG. 2D, after the signal generator 2 generates the pulse signal Vsa2 'of the positive polarity at the time of the reverse rotation of the engine, the zero-cross point θ13 of the magnet generator generated at the fourth time is generated. Becomes the hard ignition position of the first cylinder at the time of reverse rotation of the engine (position at 5 ° before the top dead center), and the magnet generator generated at the fourth time after the signal generator 2 generates the pulse signal Vsa1 ′ of the positive polarity The phase of the output voltage of the magnet generator 1 and the crank angle position of the engine such that the zero-cross point θ23 of the engine becomes the hard ignition position of the second cylinder at the time of reverse rotation of the engine (the position 5 ° before the top dead center). The relationship between is set.
[0044]
In order to detect the hard ignition position θ13 for the first cylinder at the time of reverse rotation shown in FIG. 2 (D), for example, among the zero cross points of the AC output voltage Ve, the AC output voltage starts from a negative half-wave. A zero-cross point generated when shifting to a positive half-wave is detected as a specific zero-cross point, and the signal generator generates a positive-polarity pulse signal Vsa2 ′ at the crank angle position θ22 when the engine rotates in the reverse direction. Is generated, the specific zero-cross point that occurs the second time may be detected as the hard ignition position θ13. Similarly, after the signal generator generates the positive pulse signal Vsa1 'at the crank angle position θ12 during the reverse rotation of the engine, a specific zero-crossing point occurring second time is detected as the hard ignition position θ23 for the second cylinder. can do.
[0045]
The ignition device 3 shown in FIG. 1 is attached to each of the first and second cylinders of the engine when an ignition command signal for instructing ignition of the first and second cylinders of the engine is given. The ignition device applies a high voltage for ignition to the ignition plugs P1 and P2. The ignition device includes an ignition coil IG, a primary current control circuit for causing a sudden change in the primary current of the ignition coil at an ignition position of the internal combustion engine, and It consists of.
[0046]
In the example shown in the figure, a known simultaneous firing type capacitor discharge ignition device that simultaneously applies a high voltage for ignition to the ignition plugs of two cylinders and simultaneously generates ignition sparks in the ignition plugs of both cylinders as the ignition device 3. Is used.
[0047]
The illustrated ignition device includes an ignition coil IG having one end of a primary coil grounded, and an ignition capacitor C1 provided on the primary side of the ignition coil and charged to the illustrated polarity through a diode D1 at the output of an exciter coil EX. A thyristor Th1 provided to discharge the electric charge of the capacitor C1 through the primary coil of the ignition coil IG when conducting, and a thyristor Th1 in which the charging current of the capacitor C1 flows in the forward direction. And a diode D2 connected in parallel. The ignition plugs P1 and P2 attached to the first cylinder and the second cylinder of the engine are connected between one end of the secondary coil of the ignition coil IG and the ground and between the other end and the ground, respectively.
[0048]
In the illustrated example, one end of the exciter coil EX is connected to an ignition capacitor C1 through a diode D1, and diodes D3 and D4 are connected between one end and the other end of the exciter coil EX and ground, with their anodes facing the ground. Have been.
[0049]
The above ignition device operates as follows. When the exciter coil EX induces a positive half-cycle voltage in the direction indicated by the solid arrow in the figure, the exciter coil EX-diode D1-capacitor C1-diode D2 and the primary coil of the ignition coil IG-diode D4-exciter coil (capacitor) Current flows (through the charging circuit) to charge the ignition capacitor C1 to the polarity shown. In this state, when the ignition command signal Vi is applied to the gate of the thyristor Th1, the thyristor conducts and discharges the charge of the capacitor C1 through the primary coil of the ignition coil IG. As a result, a high voltage for ignition is induced in the secondary coil of the ignition coil, and the high voltage is simultaneously applied to the ignition plugs P1 and P2. When a high voltage for ignition is applied to the spark plugs P1 and P2, spark discharge occurs simultaneously in both spark plugs, and the mixture is ignited in the cylinder of the first cylinder and the second cylinder whose ignition timing has arrived. Done. The other cylinders for which the ignition timing has not arrived are at the end of the exhaust process, so that there is no problem even if a spark discharge occurs simultaneously in the other cylinders.
[0050]
In FIG. 1, reference numeral 4 denotes a power supply circuit for converting the output of the negative half-wave of the exciter coil EX into a constant DC voltage. , A thyristor Th2 provided to bypass the charging current of the capacitor C2 flowing through the diode D5 when the transistor C2 is turned on, and a resistor connected to both ends of the capacitor C2. A voltage detection circuit comprising a series circuit of R1 and R2; a Zener diode ZD1 having an anode connected to the thyristor Th2 side between a connection point of the resistors R1 and R2 and the gate of the thyristor Th2; and a gate cathode of the thyristor Th2 And a resistor R3 connected therebetween.
[0051]
In this power supply circuit, the capacitor C2 is charged to the polarity shown in the figure by the negative half-wave output voltage of the exciter coil EX. When the voltage across capacitor C2 reaches a set value, Zener diode ZD1 conducts and a trigger signal is provided to thyristor Th2, so that thyristor Th2 conducts and prevents charging of capacitor C2. Therefore, in a steady operation state of the engine in which the engine is rotating at a speed higher than a certain rotational speed and the peak value of the output voltage of the exciter coil EX is equal to or higher than the set value, the voltage E across the capacitor C2 becomes constant. Will be kept. The voltage at both ends of the capacitor C2 is input to a regulator (voltage regulator) Reg, and a voltage of 5 [V] output from the regulator is applied to each part of the control device as a power supply voltage.
[0052]
In FIG. 1, a microcomputer 5 for controlling the ignition device 3 operates by receiving a power supply voltage of 5 [V] from a power supply circuit 4 through a regulator Reg. The output pulse of the signal generator 2 is input to the microcomputer 5 through the waveform shaping circuit 6, the output of the phase detection circuit 7 for detecting the phase of the output voltage of the exciter coil EX, and the rotation direction of the engine are inverted. A signal given from the rotation direction changeover switch 8 which is operated at the time of the operation is input. The microcomputer 5 is also connected to an ignition command signal output circuit 9 and a reverse rotation notifying circuit 10 for notifying that the engine is rotating in the reverse direction.
[0053]
The waveform shaping circuit 6 converts a pulse signal generated by the signal generator 2 into a signal having a waveform recognizable by a microcomputer. The waveform shaping circuit 6 includes transistors TR1 to TR3, resistors R4 to R9, capacitors C3 and C4, and a diode. D6 to D8. A signal obtained at the collector of the transistor TR3 and a signal obtained at the collector of the transistor TR1 of this waveform shaping circuit are input to the ports A1 and A2 of the microcomputer 5 as interrupt signals INT1 and INT2, respectively.
[0054]
In the illustrated waveform shaping circuit 6, when the negative pulse signals Vsb1, Vsb2, Vsb1 ', Vsb2' generated by the signal generator 2 exceed the voltage (threshold) across the capacitor C4, the signal coil SG A current flows through the path of the diode D8, the resistor R5, the diode D7, and the signal coil SG. This current causes a voltage drop across the diode D8 to reverse-bias the base and emitter of the transistor TR2, so that the transistor TR2 is turned off and the transistor TR3 is turned on. As described above, when the negative polarity pulse signals Vsb1, Vsb2, Vsb1 ', and Vsb2' exceed the threshold, the transistor TR3 of the waveform shaping circuit 6 is turned on, and the potential of the collector of the transistor TR3 decreases. . The microcomputer 5 recognizes that the potential of the collector of the transistor TR3 has fallen, and thereby detects that the signal generator 2 has generated a negative-polarity positive pulse signal.
[0055]
When the signal generator 2 generates pulse signals Vsa1, Vsa2, Vsa1 ', and Vsa2' of positive polarity, and these pulse signals exceed the voltage (threshold) across the capacitor C3, the signal coil SG causes a resistance. Since a base current is supplied to the transistor TR1 through R4, the transistor TR1 is turned on, and the potential of the collector of the transistor TR1 decreases. When the microcomputer 5 recognizes the decrease in the potential of the collector of the transistor TR1, it detects that the signal generator 2 has generated a positive pulse signal.
[0056]
The phase detection circuit 7 has an NPN transistor TR4 whose collector is connected to the ports A3 and A4 of the microcomputer 5 and whose emitter is grounded, and between the base of the transistor TR4 and the output terminal of the power supply circuit 4 and between the base and the emitter of the transistor TR4. It comprises resistors R10 and R11 connected to each other, and a diode D9 whose cathode is connected to the exciter coil EX side between the base of the transistor TR4 and the other end of the exciter coil EX.
[0057]
In this phase detection circuit, when the exciter coil EX is generating a negative half-wave output voltage, a base current is supplied from the regulator Reg to the transistor TR4 through the resistor R10, and the transistor TR4 is turned on. When the exciter coil EX generates a positive half-wave output voltage, the other end of the exciter coil EX has a negative potential (-0.7 V) with respect to the ground potential due to a voltage drop generated across the diode D4 due to the charging current of the capacitor C1. (Approximately [V]), the base current that has been flowing through the transistor TR4 until then flows almost to the exciter coil EX side, and the transistor TR4 is turned off.
[0058]
As described above, the transistor TR4 is turned on when the exciter coil EX is generating a negative half-wave output voltage, and is turned off when the exciter coil EX is generating a positive half-wave output voltage. At the collector of the transistor TR4, the output voltage of the exciter coil EX rises at the zero cross point when the negative half-wave shifts to the positive half-wave, and the output voltage shifts from the positive half-wave to the negative half-wave. Thus, a rectangular wave signal Vq falling at the zero crossing point is obtained. The microcomputer detects each zero cross point of the output voltage of the exciter coil by recognizing the rise and fall of the rectangular wave signal.
[0059]
In this example, as shown in FIG. 2C, the microcomputer 5 sets the zero cross point when the output voltage of the exciter coil EX shifts from the negative half wave to the positive half wave as a specific zero cross point z. Recognizes the rise of the rectangular wave signal obtained at the collector of the transistor TR4 to detect the specific zero-crossing point z. When the engine rotates in the reverse direction, the signal generator 2 generates the positive pulse signal Vsa2 '. Thereafter, the specific zero-crossing point z detected for the second time is set as the low-temperature ignition position θ13 of the first cylinder at the time of reverse rotation of the engine. Further, after the signal generator 2 generates the pulse signal Vsa1 'of the positive polarity, the specific zero-cross point z detected for the second time is set as the low-temperature ignition position θ23 of the second cylinder at the time of the reverse rotation of the engine. .
[0060]
The ignition command signal output circuit 9 has a PNP transistor TR5 having an emitter connected to the output terminal of the power supply circuit 4, a base connected to a port A5 of the microcomputer through a resistor R12, and an anode connected to the collector of the transistor through a resistor R13. The cathode of the diode D10 is connected to the gate (ignition command signal input terminal) of the thyristor Th1 of the ignition device 3 as an output terminal of the ignition command signal output circuit 9.
[0061]
As will be described later, the microcomputer 5 lowers the potential of the port A5 to almost the ground potential when the ignition position of the internal combustion engine is detected. As a result, the transistor TR5 is turned on, so that the ignition command signal Vi is supplied from the power supply circuit 4 to the ignition device 3 through the region between the emitter and the collector of the transistor TR5, the resistor R13, and the diode D10.
[0062]
The rotation direction switch 8 is a manual switch that can be switched between an off state and an on state, and is connected between the port A6 of the microcomputer 5 and the ground. The port A6 of the microcomputer 5 is connected to the output terminal of the power supply circuit 4 through the resistor 14. The microcomputer 5 determines whether a command to rotate the internal combustion engine forward or a command to rotate it reversely is given based on the state of the switch 8. In this example, it is assumed that the internal combustion engine is rotated forward when the switch 8 is in the off state, and reversely rotated when the switch 8 is in the on state.
[0063]
The reverse notification circuit 10 includes an NPN transistor TR6 having an emitter grounded and a base connected to a port A7 of the microcomputer through a resistor R15, a resistor R16 connected between the base and the emitter of the transistor TR6, and an ungrounded power supply circuit 4. A reverse lamp L as notification means is connected between the output terminal on the side and the collector of the transistor TR6. Note that the reverse lamp L may be replaced with another light emitting element such as a light emitting diode, or may be replaced with a notifying means including a sounding body such as a buzzer. Further, both the light emitting element and the sounding body may be used as the notification means.
[0064]
As described above, in the rotation direction reversal control method according to the present invention, a deceleration process of reducing the rotation speed of the internal combustion engine when a command to reverse the rotation direction of the two-stroke internal combustion engine is given, and the deceleration process Whether the rotation direction of the internal combustion engine is reversed by the over-advanced ignition process in which the internal combustion engine is ignited at the over-advanced ignition position and the ignition at the over-advanced ignition position with the rotational speed reduced below the set value Performing a rotation direction determination step of determining whether the rotation direction of the internal combustion engine has been reversed in the rotation direction determination step. The internal combustion engine is ignited at the position, and the engine is operated in a state where the rotation direction is reversed.
[0065]
When the rotation direction changeover switch is operated (when a reversal command is given), the microcomputer 5 determines the deceleration process, the over-advance angle ignition process, the rotation direction determination process, and the ignition position at the time of reversing the rotation direction. And a step of causing ignition.
[0066]
In the conventional rotation direction reversal control method, when the reversal command is given, the over-advanced ignition process is performed only once. However, in the present invention, the rotation speed of the internal combustion engine is reduced to less than a set value. In this state, when the over-advanced ignition process is performed on one cylinder of the internal combustion engine, it is determined that the rotation direction of the internal combustion engine is not reversed in the rotation direction determination process. However, the over-advanced ignition process and the rotation direction determination process are performed.
[0067]
Further, in the present embodiment, even if the over-advanced ignition process and the rotation direction determination process are performed on all the cylinders in a state where the rotation speed of the internal combustion engine is reduced below the set value, the rotation of the internal combustion engine is determined in the rotation direction determination process. When it is not determined that the direction has been reversed, the speed increasing process of increasing the rotation speed of the internal combustion engine to a predetermined speed, the deceleration process of reducing the engine speed, and the rotation speed of the engine decreasing to a set value are performed. The over-advanced ignition process of igniting the engine at the over-advanced ignition position, the rotation direction determination process of determining whether or not the rotation direction was reversed by the ignition at the over-advanced ignition position, and the rotation direction was not reversed Sometimes, the reversal control process including the step of repeating the over-advanced ignition process and the rotation direction determination process for a set number of times is performed at least once, and the rotation direction is reversed even if the reversal control process is performed a set number of times. What And so as to stop the internal combustion engine when Tsu.
[0068]
FIG. 3 shows an example of a flowchart showing an algorithm of a program executed by the microcomputer 5 in order to execute the above control method.
[0069]
The routine shown in FIG. 3 is executed at regular time intervals in order to perform the rotation direction inversion control. When this routine is started, it is first determined in step 1 whether the rotation direction switch 8 has been operated (whether there is a reversal request). As a result, if it is determined that there is no inversion request, the process returns to the main routine (not shown). If it is determined in step 1 that there is a reversal request, the process proceeds to step 2 to increment the reversal control repetition number m (initial value = 0) by 1, and proceeds to step 3 to perform deceleration control. This deceleration control is performed by stopping the supply of the ignition command signal Vi to the ignition device 3 to stop the ignition operation, or by retarding the ignition timing. Next, the routine proceeds to step 4 where the engine speed N is compared with the over-advanced ignition speed Ns which gives the upper limit of the engine speed range in which the over-advanced ignition is performed. It is determined whether it is equal to or less than Ns. As a result, when it is determined that the rotation speed N is not lower than the over-advanced rotation speed Ns, the process proceeds to step 5 to stop the ignition at the over-advanced position and continue the deceleration control. If it is determined in step 4 that the rotation speed N is equal to or lower than the over-advanced rotation speed Ns, the process proceeds to step 6 to perform ignition at the over-advanced position, and in step 7 the number of over-advanced ignitions n (Initial value = 0) is incremented by one. Next, at step 8, it is determined whether or not the rotation direction has been successfully reversed. As described above, the rotation direction of the engine is determined by looking at the polarity of the output voltage of the exciter coil EX (the output of the phase detection circuit 7) when the signal generator 2 generates a pulse signal of either polarity. Then, when the determined rotation direction matches the rotation direction requested by the inversion request, it is determined that the inversion is successful.
[0070]
If it is determined in step 8 that the reversal of the rotation direction has been successful, the process proceeds to step 9 to return the number of times of over-advanced ignition n and the number of reversal control repetitions m to 0, and to end the inversion control in step 10. (For example, a process for permitting ignition in a state where the rotation direction is reversed), and returns to the main routine.
[0071]
If it is determined in step 8 that the reversal of the rotation direction has failed, the process proceeds to step 11 to determine whether or not the number n of over-advanced ignitions is equal to a set value (2 in this example). If the number n is not equal to the set value, the flow returns to step 6 to cause ignition at the over-advanced position again.
[0072]
In the present embodiment, after performing ignition at the over-advanced position with respect to one of the cylinders, when it is determined in step 8 that the reversal of the rotation direction has failed, and when it is determined in step 11 that n = 2 is not satisfied, In step 6, the other cylinder is ignited at the over-advanced position.
[0073]
As described above, if the number of over-advanced ignitions is set to be equal to the number of cylinders 2 in the case where the internal combustion engine has two cylinders, the over-advanced ignition process for one cylinder of the internal combustion engine (step 6) ), When it is determined in the rotation direction determination step (step 8) that the rotation direction of the internal combustion engine has not been reversed, while the rotation speed of the internal combustion engine is kept below the set value, Subsequently, the over-advanced ignition process and the rotation direction determination process can be performed for other cylinders.
[0074]
If it is determined in step 8 that reversal of the rotation direction has failed even if ignition is performed at the over-advanced position in both cylinders of the engine, it is determined in step 11 that n = 2. Then, the process proceeds to step S12, where it is determined whether or not the reversal control repetition count m is equal to or greater than the set count ms. As a result, when it is determined that the number of reversal control repetitions m is not equal to or greater than the set number of times ms (the reversal control has not been performed ms times), the routine proceeds to step 13, where the number of over-advanced ignitions n is set to 0. The control for increasing the rotation speed is performed. In this control, the engine is normally ignited, and the amount of fuel supplied to the engine is increased to increase the rotation speed. Next, at step 15, it is determined whether or not the rotational speed of the engine has risen to the set value. When it is determined that the rotational speed has risen to the set value, the process returns to step 2 to increment the reversal control repetition count m by one. The steps subsequent to the deceleration control in step 3 are repeated. As a result, when it is determined in step 8 that the reversal of the rotation direction is successful, step 9 is performed, and then the process proceeds to step 10 to end the reversal control.
[0075]
If it is determined in step 8 that the reversal has failed even if the reversal control including the over-advanced ignition is repeated ms times, it is determined in step 11 that n = 2, and in step 12 m ≧ ms. Therefore, the process proceeds to step 16 to return the number n of over-advanced ignitions and the number m of reversal control to 0, and proceeds to step 17 to perform processing for stopping the internal combustion engine. The internal combustion engine is stopped by stopping the ignition operation of the ignition device and / or stopping the supply of fuel to the engine.
[0076]
The microcomputer 5 executes various routines for performing processing necessary for operating the engine in addition to the above-described routine. For example, in the main routine, initialization of each part at the time of turning on the power, permission of interruption, calculation of the ignition position of the engine with respect to the rotation speed calculated by the rotation speed calculation means, and the like are performed. Further, in an interrupt routine executed each time the signal generator 2 generates the pulse signals Vsb1 and Vsb2 or Vsb1 ′ and Vsb2 ′ of the negative polarity and is given to the microcomputer 5 by the interrupt signal INT1, the rotation speed of the engine is determined. Calculation and processing for setting a measurement value for measuring the ignition timing calculated by the ignition timer are performed. Further, in the interrupt routine that is executed when the signal generator 2 generates the pulse signals Vsa1 and Vsa2 or Vsa1 ′ and Vsa2 ′ of positive polarity and the interrupt signal INT2 is given to the microcomputer, the positive routine of the engine is performed. A process for performing hard ignition at the time of rotation, a process for starting measurement of a soft ignition position at the time of reverse rotation of the engine, or a process for permitting an interrupt by the interrupt signal INT3 to be performed at the time of reverse rotation of the engine. Perform processing, etc. Further, in a state where the interruption by the interruption signal INT3 is permitted, a zero cross point when the output of the exciter coil EX shifts from the negative half wave to the positive half wave is detected by the phase detection circuit 7, and the In an interrupt routine executed when the interrupt signal INT3 is given to the computer 5, a zero-cross point used as a hard ignition position at the time of reverse rotation of the engine is detected, and the hardware at the time of reverse rotation is detected at the zero-cross point. Processing for causing ignition is performed.
[0077]
In the case where the reversal control is performed by the algorithm shown in FIG. 3, a deceleration process for reducing the rotation speed of the internal combustion engine when the rotation direction changeover switch is operated is performed in step 3, and in step 6, the deceleration process is performed. As a result, an over-advanced ignition process is performed in which the internal combustion engine is ignited at an over-advanced ignition position in a state where the rotational speed is reduced below the set value. In step 8, a rotation direction determination process is performed to determine whether the rotation direction of the internal combustion engine has been reversed by the ignition at the over-advanced ignition position.
[0078]
That is, step 3 constitutes deceleration means for performing a deceleration process of decelerating the internal combustion engine when the rotation direction changeover switch is operated, and the state in which the rotation speed is reduced to less than the set value by the deceleration means in step 6 Thus, an over-advanced ignition means for performing an over-advanced ignition process of igniting the internal combustion engine at an over-advanced ignition position. Step 8 constitutes a rotation direction determination means for performing a rotation direction determination step of determining whether the rotation direction of the internal combustion engine has been reversed by ignition at the over-advanced ignition position.
[0079]
Further, in a state (not shown) in which hard ignition is performed in a state where the rotational direction of the engine is reversed, the rotational direction is reversed when it is determined in the rotational direction determination step that the rotational direction of the internal combustion engine is reversed. Inversion ignition control means for igniting the internal combustion engine at the ignition position in the state is constituted.
[0080]
In addition, in steps 7, 9, 10, and 11 of FIG. 3, the over-advanced ignition process by the over-advanced ignition device and the rotation direction determination process by the rotation direction determination device in a state where the rotational speed of the internal combustion engine is reduced below the set value. Is repeated up to n times (n is a set value consisting of an integer of 2 or more) until the rotation direction of the internal combustion engine is reversed.
[0081]
Further, in steps 2, 9, 12, 13 and 16 of FIG. 3, the over-advanced ignition repetitive control means performs the over-advanced ignition process by the over-advanced angle control means and the rotation direction determination process by the rotation direction determination means n times. When the rotation direction of the internal combustion engine does not reverse even after the repetition, the over-advance ignition process is repeated by the speed-up process of increasing the internal-combustion engine to a set speed, the deceleration process by the deceleration control means, and the over-advance angle repetitive control process. A reversal control repetition control means is configured to repeat the reversal control process including the rotation direction determination process up to m times (m is a set value consisting of an integer of 1 or more) until the rotation direction of the internal combustion engine is reversed.
[0082]
Step 17 constitutes engine stopping means for performing processing for stopping the internal combustion engine when the rotation direction of the internal combustion engine is not reversed even if the reversing control repetition control means repeats the reversing control process m times.
[0083]
FIG. 4 is a waveform diagram showing the operation of the internal combustion engine control device shown in FIG. FIG. 4 is a graph showing changes in waveforms of various parts from when the rotation direction changeover switch 8 is closed to when the rotation direction is reversed in a state where the engine is rotating forward, and the crank angle θ is plotted on the horizontal axis. It is shown.
[0084]
4A shows a waveform of an AC voltage output from the exciter coil EX of the magnet generator 1, and FIG. 4B shows pulse signals Vsa1, Vsb1, Vsa2, Vsb2, Vsa2, etc. generated by the signal generator 2. 3 shows the waveforms of FIG. FIG. 4C shows the waveform of the voltage Vc across the ignition capacitor C1.
[0085]
As described above, when the rotation direction switch 8 is closed, the deceleration process (Step 3 in FIG. 3) is performed. In the present embodiment, during this deceleration process, the supply of the ignition command signal Vi to the ignition device 3 is stopped, thereby causing the engine to misfire and decelerating. Therefore, when the rotation direction switch 8 is closed, the voltage Vc across the ignition capacitor C1 is maintained at a high level as shown at the left end of FIG. 4C.
[0086]
In the microcomputer, the signal generator 2 generates a pulse signal of one polarity, for example, a pulse signal of a positive polarity (in the illustrated example, a positive pulse signal Vsa1 which determines a low-speed ignition position of the first cylinder during normal rotation). At this time, since the half-wave polarity of the output voltage of the exciter coil EX is negative, it is recognized that the rotation direction of the engine is the positive direction.
[0087]
When it is detected in step 4 of FIG. 3 that the engine has been misfired and the rotational speed of the engine has fallen below a set value (for example, 500 rpm), the microcomputer issues a signal in step 6 of FIG. When the generator 2 outputs the pulse signal Vsb1 of the negative polarity at the soft ignition reference position θ12 for the first cylinder, the measured value of the over-advanced ignition position θi1 of the first cylinder (when the crankshaft of the engine has the pulse of the negative polarity) The time required to rotate from the position where the signal Vsb1 is generated to the over-advanced ignition position) is set in the ignition timer, and the measurement is started.
[0088]
The over-advanced ignition position is set, for example, at a position 40 ° (BTDC) before the top dead center of the engine. When the set over-advanced ignition position θi1 is measured, the ignition command signal Vi is given to the ignition device 3, so that the electric charge accumulated in the ignition capacitor C1 is discharged through the primary coil of the ignition coil, and the secondary of the ignition coil is discharged. A high voltage for ignition is induced in the coil. Since this high voltage is applied to the ignition plugs P1 and P2 of the first and second cylinders of the engine, sparks are simultaneously generated at these ignition plugs. Thus, the ignition operation (ignition to fuel) is performed in the first cylinder at the ignition timing. At this time, since the second cylinder is at the end of the exhaust stroke, even if a spark occurs at the spark plug P2, it is not ignited. Due to the discharge of the capacitor C1, the voltage Vc across the capacitor becomes zero.
[0089]
In the illustrated example, the first ignition at the over-advanced ignition position θi1 fails to reverse the rotation direction of the engine. Therefore, when the signal generator generates the positive polarity pulse signal Vsa1 at the position of the crank angle θ11, the microcomputer still rotates forward because the output voltage of the exciter coil is a half-wave of the negative polarity. Is detected (failure of reversing the rotation direction) (step 8 in FIG. 3).
[0090]
At this time, the microcomputer executes step 11 in FIG. 3 to determine whether or not the number of times of over-advanced ignition is two. This time, since n was set to 1 in step 7, step 6 is executed again, and the measurement value for measuring the over-advanced ignition position θi2 of the second cylinder at the soft ignition reference position θ22 for the second cylinder is Set to the ignition timer. When the ignition timer completes the measurement of the measurement value set at the over-advanced ignition position θi2, an ignition command signal Vi is given to the ignition device 3. As a result, sparks occur simultaneously in the ignition plugs P1 and P2, and the second over-advanced ignition is performed in the second cylinder at the ignition timing.
[0091]
In the illustrated example, the rotation direction of the engine is successfully reversed by the second over-advanced ignition. Therefore, when the signal generator 2 generates the pulse signal Vsa1 'of the positive polarity at the position of the crank angle θ22, it recognizes that the engine is reversing, and it is determined that the rotation direction has been successfully reversed in step 8 of FIG. Is determined. Further, a zero point for detecting the hard ignition position θ13 of the first cylinder at the time of reverse rotation at the position of the crank angle θ22 ′ (the ignition reference position for the first cylinder) (as described above, the output voltage of the exciter coil in the present embodiment) (Zero point) when the transition from the negative half-wave to the positive half-wave starts. Next, in step 9, n and m are returned to 0, and in step 10, the ignition is permitted at the normal ignition position with the rotation direction reversed, and the reversal control is ended.
[0092]
Since the hard ignition position θ13 is detected when two zeros are counted from the position of the crank angle θ22 ′ when the output voltage of the exciter coil shifts from a negative half-wave to a positive half-wave, the hard ignition position θ13 is detected. The ignition command signal Vi is given to the ignition device 3 at the position. As a result, sparks occur in the ignition plugs P1 and P2, and ignition is performed in the first cylinder at the ignition timing. As a result, the rotation of the engine with the rotation direction reversed is maintained.
[0093]
After the rotation direction of the engine is reversed as described above, when increasing the rotation speed of the engine for running a vehicle or the like, the engine is ignited at the ignition position calculated by the microcomputer, as in the case of the normal rotation. In such a manner, the ignition position is advanced as the rotational speed increases as necessary.
[0094]
In the above example, the present invention is applied to a two-cycle two-cylinder internal combustion engine, but the present invention can also be applied to a single-cylinder two-cycle internal combustion engine. When the present invention is applied to a single-cylinder internal combustion engine, the rotation angle from when the signal generator generates a positive or negative polarity pulse signal to when the positive or negative polarity pulse signal is generated again is 360 °. Therefore, the position at which the signal generator generates a pulse signal cannot be used as the measurement start position of the ignition position at the time of reverse rotation of the engine. Therefore, in this case, the specific zero-cross point of the output of the exciter coil is set as the measurement start position of the ignition position.
[0095]
In the above example, the specific zero-cross point of the output voltage of the exciter coil (coil for driving the ignition device) provided in the magnet generator is set as the ignition position at the time of reverse rotation at low speed, or the measurement of the ignition position is started. However, the zero cross point of the output voltage of the power generation coil other than the exciter coil may be used as the low-speed ignition position at the time of reverse rotation, or the ignition position measurement start position. If there is room in the output of the magnet generator and the generator coil wound around one pole of the stator can be used as a generator coil dedicated to the control device (a generator coil that does not supply power to the load), It is preferable to use the zero cross point of the output voltage of the coil as the ignition position at low speed or the measurement start position of the ignition position. By setting the zero-cross point of the output voltage of the generating coil that does not drive the load as the ignition position at low speed or the measurement start position of the ignition position, the influence of the armature reaction is eliminated, The ignition position and the measurement start position of the ignition position can be accurately determined.
[0096]
【The invention's effect】
As described above, according to the present invention, as a result of performing the over-advanced ignition process, when it is determined that the rotation direction of the internal combustion engine is not reversed in the rotation direction determination process, the over-advanced ignition process and the rotation direction are performed. Since the judgment process is repeated, it is possible to increase the chances of reversing the rotation direction, increase the probability of succeeding in reversing the rotation direction, and improve the operability when reversing the vehicle or the like. it can.
[0097]
In the present invention, if ignition of one cylinder at the over-advanced position fails as a result of reversal of the rotation direction, ignition of the other cylinder at the over-advanced position is performed. In this case, it is possible to increase the probability of successfully reversing the rotation direction even when there is a difference in combustion state between the cylinders.
[0098]
Further, in the present invention, the over-advanced ignition process and the rotation direction determination process may be performed a set number of times in a state where the rotation speed of the internal combustion engine is reduced below the set value, or may be performed for all cylinders, When it is not determined in the rotation direction determination process that the rotation direction of the internal combustion engine has been reversed, the speed increase process, the deceleration process, the over-advance ignition process, and the rotation that increase the rotation speed of the internal combustion engine to a predetermined speed are performed. If the reversal control process including the direction determination process and the process of repeating the over-advanced ignition process and the rotation direction determination process when the rotation direction is not reversed is repeated at least, the rotation direction of the engine is successfully reversed. Can be further increased.
[0099]
If the rotation direction of the engine cannot be reversed even if the above-described reversal control process is repeated a predetermined number of times, and if the engine is stopped, the reversal control is performed when the engine is difficult to reverse. Can be prevented from being repeated for an abnormally long time.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a configuration example of hardware of a reversal control device used to execute a rotation direction reversal control method for an internal combustion engine according to the present invention.
FIG. 2 is a waveform diagram showing a waveform of an output voltage of the magnet generator shown in FIG. 1 and a waveform of a pulse signal generated by a signal generator at the time of forward rotation and reverse rotation of the engine.
FIG. 3 is a flowchart showing an algorithm of a program executed by a microcomputer to perform inversion control in the control device of FIG. 1;
FIG. 4 is a waveform diagram showing an operation when a normally rotating internal combustion engine is rotated in the reverse direction.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Magnet generator, 2 ... Signal generator, 3 ... Ignition device, 5 ... Microcomputer, 6 ... Waveform shaping circuit, 7 ... Phase detection circuit, 8 ... Rotation direction changeover switch, 9 ... Ignition command signal output circuit, 10 ... Reverse rotation notification circuit.

Claims (8)

A deceleration process of reducing the rotation speed of the internal combustion engine when a command to reverse the rotation direction of the two-stroke internal combustion engine is given; and the internal combustion engine in a state where the rotation speed is reduced to less than a set value by the deceleration process And a rotation direction determining step of determining whether or not the rotation direction of the internal combustion engine has been reversed by the ignition at the over-advanced ignition position. Igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine in a state where the rotation direction is reversed when it is determined that the rotation direction of the internal combustion engine has been reversed in the rotation direction determination step, In the rotation direction reversal control method for an internal combustion engine that performs the operation of the internal combustion engine in a state where the rotation direction is reversed,
After performing the over-advanced ignition process once, when it is determined in the rotation direction determination process that the rotation direction of the internal combustion engine is not reversed, the rotation speed of the internal combustion engine is reduced to less than the set value. A rotation direction reversal control method for an internal combustion engine, wherein the over-advance angle ignition step and the rotation direction determination step are repeated at least once in a state of being left. A deceleration process of reducing the rotation speed of the internal combustion engine when a command to reverse the rotation direction of the two-cycle multi-cylinder internal combustion engine is given, and in a state where the rotation speed is reduced to less than a set value by the deceleration process, An over-advanced ignition process of igniting the internal combustion engine at an over-advanced ignition position and a rotation direction determining process of determining whether the rotation direction of the internal combustion engine has been reversed by ignition at the over-advanced ignition position. When the rotational direction of the internal combustion engine is determined to be reversed in the rotational direction determination step, the internal combustion engine is ignited at an ignition position suitable for operating the internal combustion engine with the rotational direction reversed. In the internal combustion engine rotation direction reversal control method for performing the operation of the internal combustion engine in a state where the rotation direction is reversed,
After performing the over-advance angle ignition process for one cylinder of the internal combustion engine, when it is determined in the rotation direction determination process that the rotation direction of the internal combustion engine is not reversed, the rotation of the internal combustion engine is determined. A rotation direction reversal control method for an internal combustion engine, further comprising performing an over-advanced ignition process and a rotation direction determination process for other cylinders while keeping the speed lower than the set value. . It is determined that the rotation direction of the internal combustion engine has been reversed in the rotation direction determination process even if the over-advance angle ignition process and the rotation direction determination process are performed a set number of times while the rotation speed of the internal combustion engine is reduced below the set value. If the rotation direction is not reversed, the speed increasing process of increasing the rotation speed of the internal combustion engine to a predetermined speed, the deceleration process, the over-advanced ignition process, and the rotation direction determination process are performed when the rotation direction is not reversed. A reversal control process comprising a step of repeating the advance ignition process and the rotation direction determination process is performed at least once, and the internal combustion engine is turned off when the rotation direction is not reversed even after performing the reversal control process a set number of times. 2. The method according to claim 1, further comprising: performing a process for stopping the rotation of the internal combustion engine. Even if the over-advance angle ignition process and the rotation direction determination process are performed for all the cylinders in a state where the rotation speed of the internal combustion engine is reduced below the set value, the rotation direction of the internal combustion engine is reversed in the rotation direction determination process. When it is not determined that the rotation has been performed, the speed increasing process of increasing the rotation speed of the internal combustion engine to a predetermined speed, the deceleration process, the over-advance angle ignition process, the rotation direction determination process, and the rotation direction are reversed. The reversal control process comprising repeating the over-advanced ignition process and the rotation direction determination process for a set number of times when the reversal control process is not performed. 3. The method according to claim 2, wherein the internal combustion engine is stopped when the rotation is not reversed. A rotation direction changeover switch that is operated when reversing the rotation direction of the two-cycle internal combustion engine, deceleration control means for performing a deceleration process of decelerating the internal combustion engine when the rotation direction changeover switch is operated, and the deceleration control Means for performing an over-advanced ignition process of igniting the internal combustion engine at an over-advanced ignition position in a state where the rotational speed of the internal combustion engine is reduced below a set value by the means; Rotation direction determining means for performing a rotation direction determination step of determining whether or not the rotation direction of the internal combustion engine has been reversed by the ignition at the ignition position, and that the rotation direction of the internal combustion engine has been reversed by the rotation direction determination means. A reversal point ignition control means for igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine in a state where the rotation direction is reversed when determined, the rotation direction for the internal combustion engine. In the rolling control device,
In the state where the rotational speed of the internal combustion engine is reduced to less than a set value, the over-advanced ignition process by the over-advanced ignition device and the rotational direction determination process by the rotational direction determination device are performed n times (n is an integer of 2 or more). The rotation direction reversal control device for the internal combustion engine includes an over-advanced ignition repetition control means for repeating the rotation direction of the internal combustion engine until the rotation direction is reversed up to a set value of the internal combustion engine. A rotation direction changeover switch that is operated when reversing the rotation direction of the two-cycle internal combustion engine, deceleration control means for performing a deceleration process of decelerating the internal combustion engine when the rotation direction changeover switch is operated, and the deceleration control Means for performing an over-advanced ignition process of igniting the internal combustion engine at an over-advanced ignition position in a state where the rotational speed of the internal combustion engine is reduced below a set value by the means; Rotation direction determining means for performing a rotation direction determination step of determining whether or not the rotation direction of the internal combustion engine has been reversed by the ignition at the ignition position, and that the rotation direction of the internal combustion engine has been reversed by the rotation direction determination means. A reversal point ignition control means for igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine in a state where the rotation direction is reversed when determined, the rotation direction for the internal combustion engine. In the rolling control device,
In the state where the rotational speed of the internal combustion engine is reduced to less than a set value, the over-advanced ignition process by the over-advanced ignition device and the rotational direction determination process by the rotational direction determination device are performed n times (n is an integer of 2 or more). Over-advanced ignition repetition control means that repeats until the rotation direction of the internal combustion engine is reversed up to a set value of
When the rotation direction of the internal combustion engine is not reversed even if the over-advanced ignition repetition control means repeats the over-advanced ignition process by the over-advanced angle control means and the rotation direction determination process by the rotation direction determination means n times. A reversal control comprising a speed-up process for increasing the internal combustion engine to a set speed, a deceleration process by the deceleration control means, an over-advance angle ignition process and a rotation direction determination process repeated by the over-advance angle repetition control process. Reversal control repetition control means for repeating the process up to m times (m is a set value consisting of an integer of 1 or more) until the rotation direction of the internal combustion engine is reversed;
Engine stop means for performing a process for stopping the internal combustion engine when the rotation direction of the internal combustion engine is not reversed even if the reversal control repetition control means repeats the reversal control process m times,
A rotation direction reversal control device for an internal combustion engine, comprising: A rotation direction changeover switch operated when reversing the rotation direction of the two-cycle multi-cylinder internal combustion engine; deceleration control means for performing a deceleration process of decelerating the internal combustion engine when the rotation direction changeover switch is operated; An over-advance ignition means for performing an over-advance ignition process of igniting the internal combustion engine at an over-advanced ignition position in a state where the rotation speed of the internal combustion engine is reduced to a value less than a set value by the deceleration control means; Rotation direction determining means for performing a rotation direction determining step of determining whether or not the rotation direction of the internal combustion engine has been reversed by ignition at the advanced ignition position; and the rotation direction of the internal combustion engine is reversed by the rotation direction determination means. Reversal ignition control means for igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine in a state where the rotation direction is reversed when it is determined that the rotation has been performed. In the direction reverse controller,
When the over-advanced ignition process by the over-advanced ignition device is performed on one cylinder of the internal combustion engine and the rotation direction determination device determines that the rotation direction of the internal combustion engine is not reversed, An internal combustion engine rotation control device comprising an over-advanced ignition repetition control means for repeating an over-advanced ignition process by the over-advanced ignition device and a rotation direction determination process by the rotational direction determination device with respect to another cylinder. Direction reversal control device. A rotation direction changeover switch operated when reversing the rotation direction of the two-cycle multi-cylinder internal combustion engine; deceleration control means for performing a deceleration process of decelerating the internal combustion engine when the rotation direction changeover switch is operated; An over-advance ignition means for performing an over-advance ignition process of igniting the internal combustion engine at an over-advanced ignition position in a state where the rotation speed of the internal combustion engine is reduced to a value less than a set value by the deceleration control means; Rotation direction determining means for performing a rotation direction determining step of determining whether or not the rotation direction of the internal combustion engine has been reversed by ignition at the advanced ignition position; and the rotation direction of the internal combustion engine is reversed by the rotation direction determination means. Reversal ignition control means for igniting the internal combustion engine at an ignition position suitable for operating the internal combustion engine in a state where the rotation direction is reversed when it is determined that the rotation has been performed. In the direction reverse controller,
When the over-advanced ignition process by the over-advanced ignition device is performed on one cylinder of the internal combustion engine and the rotation direction determination device determines that the rotation direction of the internal combustion engine is not reversed, Over-advanced ignition repetition control means for repeating the over-advanced ignition process by the over-advanced ignition device and the rotation direction determination process by the rotation direction determination device for other cylinders;
Even if the over-advanced ignition repetitive control means performs the over-advanced ignition process by the over-advanced angle control means and the rotation direction determination process by the rotation direction determination means for all cylinders of the internal combustion engine, When the rotation direction of the internal combustion engine is not reversed, the speed increasing process of increasing the internal combustion engine to a set speed, the deceleration process by the deceleration control means, the over-advance angle ignition process and the rotation direction repeated by the over-advance angle repetition control process Reversal control repetition control means for repeating the reversal control process comprising the determination process up to m times (m is a set value consisting of an integer of 1 or more) until the rotation direction of the internal combustion engine is reversed,
Engine stop means for performing a process for stopping the internal combustion engine when the rotation direction of the internal combustion engine is not reversed even if the reversal control repetition control means repeats the reversal control process m times,
A rotation direction reversal control device for an internal combustion engine, comprising:

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