JP2850616B2 - Ignition device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device for an internal combustion engine suitable for igniting a two-cycle internal combustion engine that easily rotates in the reverse direction.

[0002]

2. Description of the Related Art Since a two-stroke internal combustion engine tends to rotate in the reverse direction, an ignition device having a function of causing the engine to misfire when the reverse rotation of the internal combustion engine is detected has been proposed. Conventional ignition devices of this type include those disclosed in Japanese Utility Model Publication No. 3-11421 and Japanese Patent Publication No. 3-27759.

In the igniter disclosed in Japanese Utility Model Publication No. 3-11421, the phase relationship between the output of an exciter coil for supplying ignition energy and the output of a signal coil for generating a signal for determining ignition timing is determined by an electronic circuit. By making the determination, the rotation direction of the engine is detected, and when the reverse rotation of the engine is detected, the ignition operation of the ignition device for the internal combustion engine is stopped.

In the apparatus disclosed in Japanese Patent Publication No. 3-27759, a signal generator is provided with two signal coils, and the phase relationship between the outputs of the two signal coils is determined by using an electronic circuit. The rotation direction is detected, and the ignition operation of the ignition device for the internal combustion engine is stopped when the reverse rotation of the engine is detected.

[0005]

SUMMARY OF THE INVENTION In a conventional ignition device,
Since it is necessary to provide an electronic circuit for determining the rotation direction of the engine, there has been a problem that the configuration of the apparatus is complicated and the cost is increased. Especially recently, ignition devices that use a microcomputer to control the ignition timing have been widely used.However, in the case of using a microcomputer, a part that performs processing using an electronic circuit is used to reduce costs. Preferably, it is as small as possible.

In the method using two signal coils,
Since it is necessary to provide two signal generators, there is a problem that the size of the signal generator is increased and the cost is increased.

[0007] An object of the present invention is to reduce the cost by using a signal generator having only one signal emitting device and enabling the determination of the rotational direction to be performed without using an electronic circuit. To provide an ignition device for an internal combustion engine.

[0008]

According to the present invention, as shown in FIG. 1, when an ignition signal is given, a primary current of an ignition coil is controlled so that an ignition current is applied to a secondary side of the ignition coil. An ignition circuit 1 for inducing a high voltage, a rotor having a plurality of inductor magnetic poles formed of protrusions or recesses and rotated in synchronization with an internal combustion engine, and a magnetic pole facing the inductor magnetic pole of the rotor A pulse signal of a first polarity and a second signal of a second polarity when the magnetic pole faces the front edge of the rotor magnetic pole part of the rotor in the rotation direction and when the magnetic pole faces the rear edge of the inductor magnetic pole part. And a signal generator 2 having a signal generator for generating a pulse signal of a first polarity and a first level between the generation of a pulse signal of a first polarity and the generation of a pulse signal of a second polarity. And a first polarity pulse signal is generated after a second polarity pulse signal is generated. A square wave signal generating circuit 3 for generating a square wave signal having a second level until the signal is generated, and controlling supply of an ignition signal to an ignition circuit based on speed information and rotation angle information obtained from the square wave signal The present invention relates to an ignition device for an internal combustion engine including an ignition control means 4 having an ignition timing control means 5 that performs ignition.

In the present invention, the arc angle of one of the inductor magnetic pole portions of the rotor of the signal generator is set to be larger than the arc angle of the other inductor magnetic pole portion. The arc angle is θ1, the arc angle of the adjacent inductor magnetic pole portion which is located on the side where the phase is delayed from the one inductor magnetic pole portion during the normal rotation of the internal combustion engine is θ3, and the adjacent inductor magnetic pole portion is Is the arc angle of the space between the one inductor pole portion and θ
2. The arc angle of the space between the adjacent inductor magnetic pole portion and the one inductor magnetic pole portion, which is located on the side where the phase is delayed from the one inductor magnetic pole portion when the internal combustion engine rotates in the reverse direction. Is θo, the respective inductor magnetic pole portions of the rotor are provided such that the relationship of θo>θ1>θ2> θ3 is satisfied.

The ignition control means 4 sequentially compares the period TH in which the rectangular wave signal is at the first level and the period TL in which the rectangular wave signal is at the second level, and determines the period TH and the period TH. It is determined that the internal combustion engine is rotating forward when a relationship of TH> TL is established between the subsequent period TL and the internal combustion engine is rotating in reverse when only the relationship of TH <TL is established. An internal combustion engine rotation direction determining means 6 for determining that the internal combustion engine is rotating in the reverse direction, and a reverse rotation ignition operation stopping means 7 for stopping the ignition operation of the ignition circuit when the internal combustion engine is determined to be rotating in the reverse direction. Is further provided.

When the reverse rotation of the internal combustion engine is detected, the ignition timing control means 5 controls the ignition timing.
Thus, the supply of the ignition signal may be blocked, or the operation may be stopped by directly acting on the ignition circuit 1 as shown by the broken line in FIG. Generally, the ignition circuit includes a semiconductor switch that is turned on or off at the ignition timing in order to control the primary current of the ignition coil to change suddenly. By stopping the conduction, the ignition operation can be stopped. When a semiconductor switch capable of short-circuiting an ignition power supply is provided in the ignition circuit, the ignition operation can be stopped by keeping the semiconductor switch conductive.

[0012]

With the above arrangement, the rotation direction of the internal combustion engine can be detected by software using a microcomputer without using an electronic circuit. In addition, since it is not necessary to provide two signal emitting devices, it is possible to prevent the signal generator from becoming large and costly. Therefore, without increasing the size of the device and increasing the cost,
An ignition device for an internal combustion engine having a reverse rotation preventing function can be obtained.

[0013]

FIG. 2 shows a hardware configuration of an embodiment of the present invention. In FIG. 2, reference numeral 10 denotes a CPU (central processing unit) of a microcomputer, 11 denotes a RAM (random access memory), and 12 denotes a RAM. It is a ROM (Read Only Memory).

Reference numeral 1 denotes an ignition circuit, which in this example comprises an ignition coil 1A, a primary current control circuit 1B, and an ignition plug 1C attached to a cylinder of an internal combustion engine and connected to a secondary coil of the ignition coil. ing. The primary current control circuit is 1
A secondary current control semiconductor switch, and the ignition signal V
By operating the switch when i is given, the primary current of the ignition coil is rapidly changed to generate a high voltage for ignition on the secondary side of the ignition coil. As the ignition circuit, a circuit employing an arbitrary system such as a capacitor discharge type circuit or a current cutoff type circuit can be used.

The signal generator 2 includes an inductor type rotor 2A.
And signal emission 2B. The rotor 2A
A plurality of inductor magnetic pole portions 2a and 2b formed of protrusions are provided on the outer periphery of a cylindrical rotating body 200 made of a ferromagnetic material. Among the plurality of inductor magnetic pole portions, one inductor magnetic pole portion 2a has an arc angle θ1 which is different from that of the other inductor magnetic pole portion 2b.
The arc angle of the one inductor magnetic pole portion 2a is set to θ1, and one inductor magnetic pole portion 2a when the internal combustion engine is rotating forward (when rotating in the direction of arrow CW shown).
The arc angle of the adjacent inductor magnetic pole portion 2b, which is located on the side delayed in phase from that of the adjacent inductor magnetic pole portion 2b, is θ3, and the arc angle of the space between the adjacent inductor magnetic pole portion 2b and one inductor magnetic pole portion 2a. To θ
2. The adjacent inductor magnetic pole part 2 which is located on the side where the phase is delayed from one inductor magnetic pole part when the internal combustion engine rotates in the reverse direction.
Each inductor magnetic pole portion of the rotor is provided such that the relationship of θo>θ1>θ2> θ3 is satisfied, where θo is the arc angle of the space between b and one inductor magnetic pole portion 2a. ing.

The signal generator 2B has a signal coil 201 wound around an iron core (not shown) having a magnetic pole portion facing the inductor magnetic pole portion of the rotor, and a permanent magnet (not shown) for flowing a magnetic flux through the iron core. When the magnetic pole of the iron core faces the front edge in the rotation direction of the inductor magnetic pole portion of the rotor and the rear end edge of the inductor magnetic pole portion, the signal coil 201 And a second polarity pulse signal.

In this embodiment, the positive polarity pulse signal generated by the signal coil 201 is used as the first polarity pulse signal.
The signal of the negative polarity is a pulse signal of the second polarity. At the time of normal rotation of the internal combustion engine (at the time of rotation in the direction of the arrow CW shown),
The signal coil 201 alternately generates a positive pulse signal Vp1 and a negative pulse signal Vp2 as shown in FIG. When the internal combustion engine rotates in the reverse direction, a positive pulse signal Vp1 and a negative pulse signal Vp2 are alternately generated as shown in FIG. 3 (A) and 3 (C), the numbers 1 and 0 displayed near the pulse signal correspond to the numbers assigned to the magnetic poles of the inductor in FIG. That is, FIG.
In FIG. 2A, the pulse signal of the positive polarity indicated by the number 1 is the inductor magnetic pole portion 2a of the rotor of FIG.
The pulse signal of the positive polarity, which is generated when the front edge of the rotor opposes the magnetic pole of the signal emission and the number 0 is displayed, has the front edge of the inductor magnetic pole portion 2b of the rotor of FIG. Occurs when facing. In FIG. 3 (C), the pulse signal of negative polarity indicated by the number 1 is generated when the rear end edge of the inductor magnetic pole portion 2a faces the magnetic pole of the signal emission during the reverse rotation of the engine. The displayed negative pulse signal is generated when the rear edge of the inductor magnetic pole portion 2b faces the magnetic pole of the signal emission.

The output of the signal coil 201 is input to the rectangular wave signal generation circuit 3. The rectangular wave signal generation circuit 3 is, for example,
The flip-flop circuit is set by a positive pulse signal Vp1 and reset by a negative pulse signal Vp2. After a positive (first polarity) pulse signal is generated, a negative (second (Polarity) takes a first level until a pulse signal of the same polarity is generated, and takes a second level from the generation of the pulse signal of the second polarity to the generation of the first polarity pulse signal. Generate a wave signal.
In this embodiment, the rectangular wave signal generating circuit 3 receives the pulse signal of FIG. 3A as an input, outputs a rectangular wave signal Vq as shown in FIG. 3B, and converts the pulse signal of FIG. A rectangular wave signal Vq as shown in FIG.
That is, in this embodiment, the higher level of the rectangular wave signal Vq is set to the first level, and the lower level (zero level) is set to the second level.
And the level.

As is clear from FIGS. 3B and 3D, during the normal rotation of the engine, a period TH during which the rectangular wave signal is at a high level, and a period at a zero level generated following the period TH. The relationship of TH> TL is established with TL,
During the reverse rotation of the engine, the relationship of TH> TL is not established. In the present invention, the forward rotation and the reverse rotation of the engine are detected on software using this relationship.

The microcomputer calculates the square wave signal Vq
With the input as the input, the ignition control means 4 including the ignition timing control means 5, the internal combustion engine rotation direction judging means 6, and the reverse rotation ignition operation stopping means 7 is realized in accordance with the algorithm shown in FIGS.

FIG. 7 is a general flowchart showing the algorithm of the processing in the main routine. First, in the main routine, initialization of each section is performed, interrupts are permitted, and then the engine speed is calculated and ignition at each speed is performed. The calculation of the timing advance angle is repeated. The calculation of the number of revolutions is performed, for example, from the time required for the engine to rotate in a 360-degree section from the detection of the narrow rectangular wave signal at the angle θa to the angle θa at which the next narrow rectangular signal is detected. Is calculated.

FIG. 8 shows a rotation speed region determination routine executed every time the rotation speed is calculated. In this routine, first, the rotation speed N is compared with the advance start rotation speed N1, and N ≧ N1. At the time, the speed area determination flag FLG1 is set in the RAM, and when N <N1, the flag FLG1 is reset.

FIG. 9 is an interrupt routine executed each time a positive rise of the rectangular wave signal Vq is detected. In this routine, first, a period TH during which the rectangular wave signal Vq is at a high level and the rectangular wave When the relationship of TH> TL is detected at the positive rise of the rectangular wave signal (the positive rise at the angle θa in the example of FIG. 3) by successively comparing the period TL during which the signal is at the zero level. The reference flag FLGo is set, and then a pulse number "0" indicating that the next pulse signal generated from the signal coil is a pulse signal generated at the front edge of the inductor magnetic pole portion 2b is set. Next, it is determined whether or not the speed region determination flag FLG1 is set. If the flag FLG1 is not set (when the engine speed N is equal to or less than the set value N1), the ignition operation (the ignition circuit 1 The operation of giving the ignition signal Vi) is performed, and the processing of this routine is terminated. That is, when the rotational speed N of the engine is less than the advance start rotational speed N1, the ignition operation is performed at the positive rise θa of the square wave signal when TH> TL is detected. When the flag FLG1 is set (when the rotation speed N is equal to or more than the advance start rotation speed N1),
Return to the main routine without performing the ignition operation.

When TH <TL is detected at the positive rise of the rectangular wave signal (the positive rise at the angle θb in the example of FIG. 3), it is first determined whether or not the reference flag FLGo is set. When the flag FLGo is set (when the engine is rotating forward), the reference flag F
After resetting LGo, a pulse number "1" indicating that the next pulse signal to be generated is a signal generated at the front edge of the inductor magnetic pole portion 2a is set. Next, the flag FLG1
Is set or not. If the flag FLG1 is set (when the engine speed N is equal to or higher than the advance start rotation speed N1), the advance angle counter is started and the calculation is performed in the main routine. Measure the advance angle that is
At the time when the advance angle is measured, an ignition signal is given to the ignition circuit. If the flag FLG1 is not set (the engine speed N is less than the advance start rotation speed), the process returns to the main routine without starting the advance counter.

If TH <TL is detected at the positive rise of the rectangular wave signal and the reference flag FLGo is not set (during reverse rotation of the engine), the routine immediately returns to the main routine. When the reverse rotation of the engine is detected as described above, the process returns to the main routine without performing the ignition operation or the start of the advance angle counter. Therefore, the ignition operation is not performed and the engine is misfired.

According to the above-described embodiment, as shown in FIG. 6, when the engine speed N is less than the advance start rotation speed N1, the ignition is performed at the angle θa, and the ignition is performed in the region of the advance start rotation speed N1 or more. The lead angle characteristic of leading to θc is obtained. Angle θb is the start position of the advance counter.

In the above embodiment, the rotor of the signal generator has two inductor magnetic pole portions 2a and 2b, but three or more inductor magnetic pole portions may be provided. For example, as shown in FIG. 4, the rotor 2A can be provided with six inductor magnetic pole portions 2a to 2f. In this example, of the plurality of inductor magnetic pole portions, one of the inductor magnetic pole portions 2a has an arc angle θ1 set to be larger than that of the other inductor magnetic pole portions 2b to 2f. The arc angle of the inductor magnetic pole portion 2a is θ1, and the adjacent magnetic pole portion 2a is located on the side where the phase is delayed from that of one inductor magnetic pole portion 2a during normal rotation of the internal combustion engine (when rotating in the direction of the arrow CW shown). The arc angle of the inductor magnetic pole portion 2b is θ3, the arc angle of the space between the adjacent inductor magnetic pole portion 2b and one inductor magnetic pole portion 2a is θ2, and one inductor magnetic pole during reverse rotation of the internal combustion engine. The adjacent inductor magnetic pole portion 2f and one inductor magnetic pole portion 2 which are positioned on the side delayed in phase from the portion 2a
θo is the arc angle of the space between
Each inductor magnetic pole portion of the rotor is provided so that the relation of>θ1>θ2> θ3 is satisfied.

In this case, the signal coil 2
The pulse signal obtained from 01 is as shown in FIG. 5A, and the pulse signal obtained from the signal coil 201 at the time of reverse rotation of the engine is as shown in FIG. 5C. FIG. 5 (A),
The numbers assigned to the respective pulse signals in (C) correspond to the numbers assigned to the inductor magnetic pole portions 2a to 2f of the rotor of the signal generator in FIG.

The rectangular wave signals Vq obtained by inputting the pulse signals of FIGS. 5A and 5C to the rectangular wave signal generating circuit are as shown in FIGS. 5B and 5D, respectively.
As is apparent from these figures, the relationship of TH> TL is always detected at the time of the forward rotation of the engine, but this relationship is not detected at the time of the reverse rotation of the engine, so it is determined whether or not TH> TL is satisfied. Thus, forward rotation and reverse rotation of the engine can be detected.

In the above embodiment, the magnetic pole portion of the inductor is formed of a protrusion, but the magnetic pole portion of the inductor causes a change in the magnetic flux interlinking with the signal coil when facing the magnetic pole of the signal emission. As long as it is provided, each inductor magnetic pole portion may be formed of a concave portion.

[0031]

As described above, according to the present invention, the rotation direction of the internal combustion engine can be detected on software using a microcomputer without using an electronic circuit. Also, since it is not necessary to provide two signal emitting electrons,
It is possible to prevent the signal generator from increasing in size and increasing the cost. Therefore, according to the present invention, there is an advantage that an ignition device for an internal combustion engine having a reverse rotation preventing function can be obtained without increasing the size of the device and increasing the cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention.

FIG. 2 is a configuration diagram illustrating a hardware configuration according to an embodiment of the present invention.

FIGS. 3A and 3B are waveform diagrams showing a waveform of a pulse signal obtained from the signal generator of the embodiment of FIG. 2 and an output waveform of a rectangular wave signal generation circuit at the time of forward rotation of the engine.
FIGS. 3C and 3D are waveform diagrams showing a waveform of a pulse signal obtained from the signal generator of the embodiment of FIG. 2 and an output waveform of a rectangular wave signal generating circuit when the engine is rotating in reverse.

FIG. 4 is a configuration diagram showing a modified example of the signal generator used in the present invention.

FIGS. 5A and 5B are waveform diagrams showing a waveform of a pulse signal obtained from the signal generator of FIG. 4 and a waveform output from a rectangular wave signal generation circuit when the engine rotates forward; FIGS. 4C and 4D are waveform diagrams showing a waveform of a pulse signal obtained from the signal generator of the embodiment of FIG. 4 and an output waveform of the rectangular wave signal generation circuit when the engine rotates in the reverse direction.

FIG. 6 is a diagram showing an example of an advance angle characteristic obtained by an embodiment of the present invention.

FIG. 7 is a flowchart showing an algorithm of a main routine executed by the microcomputer in the embodiment of the present invention.

FIG. 8 is a flowchart illustrating a speed region determination routine that is performed each time a rotational speed is calculated in the embodiment of the present invention.

FIG. 9 is a flowchart showing an interrupt routine executed each time a rectangular wave signal rises in the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ignition circuit, 2 ... Signal generator, 3 ... Square wave signal generation circuit, 4 ... Ignition control means, 5 ... Ignition timing control means, 6 ... Internal combustion engine rotation direction determination means, 7 ... Reverse rotation ignition operation stop means .

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-177460 (JP, A) JP-A-2-3067 (JP, U) JP-A-53-9517 (JP, U) JP-A-1 174543 (JP, U) Shokai 59-27159 (JP, U) (58) Fields studied (Int. Cl. ⁶ , DB name) F02P 11/02 303 F02P 7/067 -7/077 F02D 17/04

Claims (1)

(57) [Claims] An ignition circuit for controlling a primary current of an ignition coil to generate a high voltage for ignition on a secondary side of the ignition coil when an ignition signal is applied; A rotor having a plurality of magnetic pole portions and rotated in synchronization with the internal combustion engine, and a magnetic pole facing an inductor magnetic pole portion of the rotor, wherein the magnetic poles rotate in the direction of rotation of the inductor magnetic pole portion. A signal generator comprising: a signal generator for generating a pulse signal of a first polarity and a pulse signal of a second polarity when facing the front edge and when facing the rear edge of the inductor magnetic pole portion, respectively. Taking a first level from the generation of the first polarity pulse signal to the generation of the second polarity pulse signal;
A rectangular wave signal generation circuit for generating a rectangular wave signal having a second level from the generation of the second polarity pulse signal to the generation of the first polarity pulse signal; An ignition control means having an ignition timing control means for controlling the supply of an ignition signal to the ignition circuit based on the speed information and the rotation angle information, wherein the ignition of the rotor of the signal generator The arc angle of one inductor magnetic pole portion is set to be larger than the arc angle of the other inductor magnetic pole portion, the arc angle of the one inductor magnetic pole portion is set to θ1, and the one of the inductor magnetic pole portions is set at the time of normal rotation of the internal combustion engine. The arc angle of the adjacent inductor magnetic pole portion, which is located on the side delayed in phase from the inductor magnetic pole portion, is θ3, and the space between the adjacent inductor magnetic pole portion and the one inductor magnetic pole portion is The arc angle is set to θ2, and when the internal combustion engine rotates in the reverse direction, When the arc angle of the space between the adjacent inductor magnetic pole portion which is located on the side delayed in phase from the inductor magnetic pole portion and the one inductor magnetic pole portion is θo,
Each of the inductor magnetic pole portions of the rotor is provided so as to satisfy the relationship of o>θ1>θ2> θ3, and the ignition control means includes a period TH during which the rectangular wave signal is at the first level and the rectangular wave. The signal is successively compared with the period TL in which the signal is at the second level, and when the relationship of TH> TL is established between the period TH and the period TL occurring subsequent to the period TH, the internal combustion engine rotates forward. The internal combustion engine rotational direction determining means determines that the internal combustion engine is rotating reversely when only the relationship TH <TL is satisfied, and the internal combustion engine is rotating reversely by the internal combustion engine rotational direction determining means. An ignition stop means for stopping the ignition operation of the ignition circuit when it is determined that the ignition circuit is stopped.