JPH0325635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a magnet generator type non-contact ignition device, particularly an electronic advance magnet with a step.

In order to reduce the degree of so-called butting that occurs when starting an internal combustion engine, there is a need for a so-called electronic advance magneto with a step that delays the ignition timing at startup compared to when idling. The required ignition timing pattern is obtained by arranging two sensors, but this conventional method requires two sensors, so it is expensive.
There are disadvantages such as reduced system reliability and disadvantages in terms of engine layout. Note that conventionally,
JP-A-56-143351 discloses a non-contact ignition device that controls ignition timing using one sensor, but this conventional device does not provide the desired stepped ignition timing characteristics.

The present invention has been made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide an ignition device that can obtain stepped ignition timing characteristics using a single sensor.

Therefore, in a non-contact ignition device that controls ignition timing using one sensor, the alternating voltage of the first system of the signal coil changes the phase of the voltage generated in the capacitor charging coil and the signal coil of the sensor. The alternating voltage of the second system is generated on the positive side of the voltage of the coil and on the negative side of the voltage of the charging coil, and the signal voltage of the first and second systems generated in the signal coil of the sensor is the voltage of the charging coil. In addition, the signal voltage of the second system is further stratified by a timer circuit triggered by the voltage of the signal coil to obtain stepped ignition timing characteristics.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the entire circuit of one embodiment of the present invention,
1 is a capacitor charging coil, 2 is a diode, 3
is an ignition capacitor, and 4 and 5 are the primary and secondary coils of the ignition coil IG, which form a capacitor discharge type ignition circuit. 7 and 8 are diodes, 9 is a power supply capacitor for an ignition timing calculation circuit to be described later, and 10, 11, and 12 are regulating thyristors, resistors, and Zener diodes. Reference numerals 8 to 12 form a regulator circuit R. 13, 14, 15, 16, 17 are resistors, diodes, resistors, resistors, and transistors that detect the negative voltage of the charging coil 1; 18, 1
9 and 20 are a resistor, a transistor that becomes conductive when the voltage in the coil 1 is in a negative direction, and a resistor, and the symbol 15
to 20 form a stratified circuit L, 21
is a signal coil of the timing sensor, and 22 and 23 are diodes. 24, 25, 26, 26a are resistors, 27, 28, 29, 30 are comparator 3
1 and 32 are resistors that create the reference voltage, 33 is an R-S flip-flop, 34 is an analog switch that becomes conductive when the Q output of flip-flop 33 becomes "1", 35 and 36 are constant current circuits, and 37 is a calculation capacitor. , 39 reset the charge on the capacitor 37. (to zero) analog switch,
39 and 40 are resistors for creating a reference voltage for the comparator 41, 42 is an AND circuit, 43 is an OR circuit, 44 is a diode, and 25 to 43 form an ignition timing calculation circuit G. 45 is a diode, and 46 is a resistor. 47 is a transistor, 4
8 is a resistor, 49 is a transistor, 50, 51, 5
2, 53, 54, 55 are resistors, 56 is a timer capacitor, 57, 58 are resistors, 59, 60 are transistors, and 47 to 60 form a timer circuit T. Note that 61 indicates a spark plug.

FIG. 2 is a structural diagram of the magneto according to the present invention, where 100 is a magnet rotor equipped with a sensor protrusion on the outer periphery, 200 is a sensor with a built-in signal coil 21, and 300 is a capacitor charging coil 1 and other output coils. A stator is shown. Further, FIG. 3 shows the ignition timing pattern of this embodiment. FIG. 4 shows voltage waveforms at various parts. Figure 4 a shows the no-load voltage of capacitor charging coil 1, and b shows signal coil 2.
1 voltage, c is the output of comparator 32, d is the output of comparator 31, e is flip-flop 3
3's Q output, f is the voltage of the calculation capacitor 37,
g indicates the voltage of the timer capacitor 56, and h indicates the voltage of the ignition capacitor 3. Rotor 1
When 00 rotates once, since the stator 300 has 12 poles, the voltage shown in FIG. 4a is generated in the capacitor charging coil 1, and the voltage shown in FIG. 4b is generated in the signal coil 21 of the timing sensor 200. Voltage is generated. The phase of the voltage a of the charging coil 1 and the signal voltage b is determined by the signal voltages S ₃ and S ₄ (especially the voltage S ₄ ) of the second system within the negative polarity of the voltage of the charging coil 1.
Each part is arranged so that it fits.
The positive polarity of the charging coil 1 contains signal voltages S ₁ and S ₂ of the first system. The positive direction output of the capacitor charging coil 1 causes a current to flow through the diode 2, the capacitor 3, the primary coil 4 of the ignition coil IG, and the diode 7, charging the ignition capacitor 3 and obtaining a power source for ignition. In addition, the negative direction voltage is generated by a diode 8, a capacitor 9, a resistor 13,
A current flows through the current and diode 14 to charge the power supply capacitor 9 and obtain power for each IG of the ignition timing calculation circuit G and other circuits (Zener diode 12, resistor 11 and thyristor 1).
0 is the regulator circuit of the power supply capacitor 9). At the same time, the negative direction output causes current to flow through diode 7, resistors 16 and 15, and diode 14, making transistor 20 conductive. on the other hand,
The signal coil 21 of the timing sensor 200 includes
The voltage shown in Figure 4b is generated, and the positive direction output
The resistors 27, 28, 26a, 26, 25 are connected so that the comparator 31 outputs "1" by S ₁ and S _3.
Each value is determined. Also, transistor 4
7 becomes conductive, the ignition thyristor 6 is made conductive through the transistor 47 and the diode 45, and the plug 61 is ignited. For the negative direction outputs S ₂ and S ₄ , the respective resistance values are set so that the transistors 59 and 60 are conductive and the timer capacitor 56 is charged. The voltage of the charged capacitor 56 is discharged with a time constant determined by the resistors 52 and 51 as shown in FIG. When the capacitor charging coil 1 outputs in the negative direction, the transistors 17 and 19 are conductive as described above, so the negative output S ₄ of the signal coil 21 that occurs when the coil 1 outputs in the negative direction is connected to the negative terminal of the comparator 32 ( -) in the negative direction. At this time, the values of the resistors 29 and 30 are determined so that "1" is output to the comparator 32 (Fig. 4c).
When "1" is output, the flip-flop 33 is reset, the analog switch 38 is closed via the OR circuit 43, the calculation capacitor 37 is reset, the thyristor 6 is made conductive via the OR circuit 43 and the diode 44, and the plug 61 is turned on. ignite and do.

The operation will be explained below based on the above settings. first,
The operation at low speed (at the time of starting the internal combustion engine) where the rotational speed is less than N ₁ in FIG. 3 will be explained. When the rotor 100 rotates, a voltage shown in FIG. 4a is generated in the capacitor charging coil 1, and the ignition capacitor 3 is
The battery is charged in a stepwise manner as shown in Fig. 4h. The power supply capacitor 9 is charged by the negative output of the charging coil 1, and the calculation capacitor 37 is charged with a constant current via the constant current circuit 36 as shown in FIG. 4f. Next, a positive voltage _S1 is generated in the signal coil 21, "1" is output from the comparator 31, the Q output of the flip-flop 33 is reset to "1", and the analog switch 34 is closed. starts constant current discharge via the constant current circuit 35 and switch 34 as shown by the solid line in FIG. 4f. On the other hand, while the negative voltage _S2 is not generated in the signal coil 21, the transistor 60 is not yet conductive and the transistors 49 and 47 are also cut off (off), so nothing is output to the thyristor 6. Not done. When the rotor 100 further rotates and voltage S ₂ is generated in the signal coil 21, the diode 22
The base of transistor 60 is negatively biased through , causing transistor 60 to conduct and charge timer capacitor 56 . The charged charges are discharged by the resistors 52 and 51 as shown by the solid line in Figure 4g,
Transistor 49 is conductive for a certain period of time and transistor 47 is also conductive, but at low rotations less than N ₁ rotation, other signal voltages are applied to transistor 4 during this period.
Since the time constant is set so as not to enter 7, nothing is output to the thyristor 6. Further, since the charging coil 1 is a positive output, the transistors 17 and 19 of the stratified circuit L are cut off, so the voltage S ₂ is not output to the comparator 32 either. Next, even if a positive signal voltage S ₃ is generated, since the transistor 47 of the timer circuit T has already been cut off, this voltage S ₃ is not input to the thyristor 6, but is input to the positive terminal of the comparator 31. 4
As shown in FIG. d, an output "1" is output, but only a set signal is input to the set flip-flop 33, and no ignition operation is performed. And finally,
When a negative signal voltage S ₄ is generated in the coil 21 as shown in FIG. 4b, the timer capacitor 56 is charged by the same operation as the voltage S ₂ described above. At the same time, since the transistor 17 of the stratified circuit L is conductive due to the negative output of the capacitor charging coil 1, the transistor 19 is also conductive, and the negative terminal of the comparator 32 is pulled by the signal voltage _S4 and becomes "1". Output.
When the comparator 32 outputs "1" (FIG. 4c), it resets the flip-flop 33 and at the same time outputs it to the gate of the thyristor 6 via the OR circuit 43 and the diode 44.
conducts and ignites the plug 61. The output of the OR circuit 43 is also applied to the analog switch 38, and when this switch 38 closes, the charge in the calculation capacitor 37 is instantly discharged and reset (FIG. 4f). The above operation is repeated for less than N ₁ rotations as shown in the third figure, and the ignition timing θ ₁ (retard) determined by the generation position of the signal voltage S ₄ is obtained.

When N ₁ rotation is reached, the discharge time of the timer capacitor 56 in the timer circuit T described above reaches the 4th rotation.
The signal voltage S 3 becomes relatively long as shown in the dashed line in Figure G, and the signal voltage S ₃ is generated while the transistor 47 is conducting, so the signal voltage S ₃ makes the thyristor 6 conductive via the diode 45 and ignites. . Therefore, at the rotational speed _N1 shown in FIG. 3, a step occurs in the ignition timing _θ2 determined by the generation position of the signal voltage _S3 . In addition, at rotation speed N ₁ , the next signal voltage
Even if the _thyristor 6 is made conductive by the output "1" appearing in the comparator 32 as shown in FIG. Reset capacitor 37. As above, N ₁
During rotation, the ignition timing steps from θ ₁ to θ ₂ , and ignition by signal voltage S ₃ is repeated up to N ₂ rotations.

As the rotation of the rotor 100 increases, the charging time of the calculation capacitor 37 of the ignition timing calculation circuit G becomes shorter, so the voltage of this capacitor 37 gradually decreases, and when the rotation reaches N ₂ rotations, the calculation capacitor 37 is charged. When the voltage at the time of current discharge reaches (reduces) the reference voltage V _TH as shown in Fig. 4 f, and exceeds _N2 rotations, the voltage due to the discharge of the calculation capacitor 37 reaches the comparator 4 regardless of the position where the signal voltage S ₂ etc. is generated.
When the reference voltage V _TH of 1 is reached, the comparator 41 outputs "1", and the AND circuit 42,
The thyristor 6 is made conductive via the OR circuit 43 and the diode 44 to perform the ignition operation. This operation is repeated until N ₃ rotations, and constant current charging, constant current discharging, and constant voltage detection are performed, so as the rotation speed increases, the charging time of the calculation capacitor 37 becomes shorter, and the voltage at the start of discharge becomes lower. As the ignition timing increases, the ignition timing advances linearly. Therefore, from _N2 rotations to _N3 rotations, a linear advance characteristic as shown in FIG. 3 is obtained.

After _N3 rotations, as shown by the two-dot chain line _{in FIG} . Output “1” is generated from When the signal voltage _S1 is applied from the coil 21 to the comparator 31, it is applied to the thyristor 6 via the Q terminal of the flip-flop 33, the AND circuit 42, the OR circuit 43, and the diode 44.
conducts and ignites. The positive signal voltage S ₃ and the negative signal voltage S ₄ also cause the thyristor 6 to conduct, but since the capacitor 3 has no charge, it does not ignite. Further, the ignition timing calculation circuit G is reset by the negative signal voltage _S4 , and the ignition operation by the signal voltage _S1 is repeated (the voltage _S2 makes the timer circuit T conductive for a predetermined period). When _N3 rotations are exceeded, the charging voltage of the capacitor 37 becomes lower than the reference voltage of the comparator 41 when the signal voltage _S1 is generated.
Based on the output of the comparator 31 based on this voltage _S1 , the thyristor 6 is made conductive and ignited.

To summarize the above operation, for less than N ₁ rotation, the ignition timing θ ₁ is fixed, which is determined by the position where the negative signal voltage S ₄ is generated, and for N ₁ rotation, the positive signal voltage S ₃ is changed from the voltage S ₄ due to the conduction of the timer circuit T. The ignition timing is stepped to θ ₂ due to the ignition timing. From N ₁ to N ₂ rotations _, the ignition timing is fixed by voltage S _3. From N ₂ to N ₃ rotations, the ignition timing is linearly advanced by the calculation circuit G, and from N ₃ rotations or more, the ignition timing is advanced by a signal. Fixed ignition timing θ ₃ determined by the location of voltage S ₁
It is possible to obtain the following characteristics.

Note that in the above embodiment, the signal coil 21
Although the negative direction voltage of the capacitor charging coil 1 was used to stratify the signal voltage of the capacitor charging coil 1, the positive direction voltage of this coil 1 may also be used. The output voltage of a separately provided sensor may also be used. Also,
In the above embodiment, the present invention was explained assuming that the number of poles of the rotor 100 and stator 300 was 12.
Other numbers of poles such as 8 poles may be used.

As described above, the present invention includes a capacitor discharge type ignition circuit, one sensor that outputs two systems of alternating signal voltages per rotation of a magnet generator, and a signal voltage of one polarity of this sensor. At the same time, a signal is output to the ignition circuit, the calculation capacitor is reset, and constant current charging is started.When a signal voltage of another polarity is introduced, constant current discharging is started, and when the constant voltage is reached, a signal is output to the ignition circuit. An ignition timing calculation circuit that outputs a signal, a positive or negative output voltage when the sensor generates the first system signal voltage, and a negative or positive output voltage when the sensor generates the second system signal voltage. a stratified circuit that conducts at the latter voltage of the coil, and a timer circuit that conducts for a predetermined period of time depending on the voltage value of one of the polarities of the sensor; A signal voltage of one polarity can be introduced into the arithmetic circuit via a stratified circuit, a signal voltage of another polarity can be added to the arithmetic circuit, and this signal voltage can be introduced into the ignition circuit via a timer circuit. Therefore, the alternating signal voltage of the sensor can be stratified, even if the signal voltage has the same polarity,
By not activating the ignition circuit depending on the voltage of one polarity of the first system, and activating the ignition circuit via the stratification circuit and the calculation circuit depending on the voltage of the same polarity of the second system, The advantage is that it is possible to provide an ignition device with stepped ignition timing characteristics. Moreover, since only one sensor is provided, there are many excellent effects such as low cost, increased system reliability, and advantages in terms of engine layout.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing an embodiment of the present invention;
Fig. 2 is a structural diagram of the magnet generator in the above embodiment, Fig. 3 is a characteristic diagram showing the ignition timing pattern of the device of the present invention, and Fig. 4 is a characteristic diagram showing voltage waveforms at various parts of the circuit shown in Fig. 1. It is. 1... Capacitor charging coil, 3... Ignition capacitor, 4, 5... Primary coil and secondary coil of ignition coil, 6... Thyristor, 21... Signal coil, 100... Rotor, 200... Sensor, G...Ignition timing calculation circuit, L...Layered circuit,
T...Timer circuit.

Claims (1)

[Claims] 1. A capacitor discharge type ignition circuit, one sensor that outputs two systems of alternating signal voltages per rotation of the magnet generator, and a signal output to the ignition circuit when a signal voltage of one polarity of this sensor is introduced. At the same time, the calculation capacitor is reset and constant current charging is started, and when a signal voltage of another polarity is introduced, constant current discharge is started, and when the constant voltage is reached, a signal is output to the ignition circuit. an arithmetic circuit, and a phase configured to generate a positive or negative output voltage when the sensor outputs the signal voltage of the first system, and generate a negative or positive output voltage when the sensor outputs the signal voltage of the second system. a stratified circuit that conducts at the latter voltage of the coil; and a timer circuit that conducts for a predetermined period of time depending on the voltage value of the one polarity of the sensor; A signal voltage of the other polarity can be introduced into the arithmetic circuit through the stratification circuit, a signal voltage of the other polarity can be applied to the arithmetic circuit, and this signal voltage can be introduced into the ignition circuit through the timer circuit. A magnetic generator type non-contact ignition device characterized by the following.