JPS6358261B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an ignition timing control device for an internal combustion engine, such as an outboard motor engine, and particularly relates to an ignition timing control device for an internal combustion engine, for example, an outboard motor engine, and in particular, it relates to an ignition timing control device for an internal combustion engine, such as an outboard motor engine, and in particular, to The present invention relates to an ignition timing control device that improves the stability of an engine during rotation.

[Prior art] In order to ensure reliable starting of outboard motors, etc., the ignition timing at startup is set to Before Top Dead Center.
(BTDC; TDC is top dead center) and set the ignition timing to about 5 degrees, and during idle rotation, set the ignition timing to After Top Dead Center to stabilize the rotation speed at low speed.
(ATDC) is set at approximately 5 degrees, and when accelerating, the ignition timing is advanced to 25 to 30 degrees BTDC at the same time as the engine throttle valve is opened to increase acceleration. However, it is extremely complicated to obtain the above-mentioned characteristics with an automatic advance mechanism, so in conventional ignition timing control devices, the stator of the ignition signal generator is usually rotatably mounted, and the stator and the It has a relatively complicated structure in which the throttle lever of the engine is interlockably connected by a ball joint, and the stator of the signal generator is rotatable and fixed in the axial direction. However, when the signal generator is rotatably provided, mechanical parts such as a bearing, a holding member for fixing in the axial direction, and a ball joint connected to the throttle lever are likely to wear out, and the engine The vibration caused damage.

In addition, some ignition timing control devices are used that advance the ignition timing according to the engine speed using the output of the signal generator. sex is not improved. Furthermore, the ignition timing control device described in US Pat. No. 4,244,336 uses a method of advancing the ignition timing in a chevron shape in a low speed range. However, although this method provides stability during idling, the starting performance and acceleration performance are poor.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional device, and it uses the delayed side signal from the signal generating means as the first ignition signal, and also adjusts the ignition timing based on the advanced side signal. A control circuit produces a second ignition signal and a third ignition signal delayed from the first ignition signal, and advances the second ignition signal when the throttle valve is fully open, and By retarding the second ignition signal when the tuttle valve is fully closed, acceleration and deceleration of the engine are improved, and when the engine is rotating at a low speed at a predetermined rotation speed, the second ignition signal is retarded. By igniting with the ignition signal No. 3, the rotation speed of the engine is lowered than when the engine is ignited with the first ignition signal, and the stability is improved and the rotation range in which the engine can stably operate is expanded. The purpose is to provide an ignition timing control device.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 1 is a circuit diagram of an ignition timing control device according to an embodiment of the present invention, and FIG.
3 is a diagram showing the configuration of a magnet generator, FIG. 3 is a diagram showing changes in signals in the main parts of the ignition timing control device shown in FIG. 1, and FIG. 4 is a diagram showing the advance angle characteristics of the ignition timing.

In FIGS. 1 and 2, 1 is a magnet generator. Reference numeral 1a denotes a power generating coil provided in the magnet generator 1 as an ignition power source, which generates voltage according to the rotation of an engine (not shown) and supplies the power necessary for igniting the engine. 1b is a signal coil provided as a signal generating means, 1c is a rotor, 1
d is a signal pole provided on the outer surface of the rotor 1c, 1e is a signal core around which the signal coil 1b is wound, and 1f is a magnet fixed to the signal core 1e. Due to the rotation of the rotor 1c, the signal pole 1d
changes the magnetic resistance of the signal core 1e, and the magnet 1f
When the magnetic flux is changed, positive and negative AC voltages are generated in the signal coil 1b. In other words, signal pole 1d
When one end 1g passes through the signal core 1e, a negative pulse voltage, which is a leading signal, is generated, and when the other end 1h of the signal pole 1d passes, a positive pulse voltage, which is a delayed signal, is generated. . Between the positive and negative pulse voltages, there is an angular difference θ approximately comparable to the arc angle of the signal pole 1d, as shown in FIG.

In FIG. 1, 2 is a diode that rectifies the output of the generator coil 1a, 3 is a capacitor that charges the output of the generator coil 1a, and 4 is the ignition coil of the engine, which includes a primary coil 4a and a secondary coil 4b. has. 5 is a spark plug. 6 is a thyristor provided as a switching element,
The electric charge charged in the capacitor 3 from the generator coil 1a is supplied to the ignition coil 4 at a predetermined time. 6a
is the gate of thyristor 6. Signal coil 1b
applies a positive pulse voltage, which is a delayed signal, to the gate 6a of the thyristor 6 as a first ignition signal. Reference numeral 7 denotes an engine operating state detection means, which divides the output of the generating coil 1a by a diode 7a,
Capacitor 7c is charged via resistor 7b. Zea diode 7d regulates the terminal voltage of capacitor 7c. The resistor 7b and the capacitor 7c constitute a time constant circuit from when the power generating coil 1a starts generating power until a predetermined voltage is obtained, and serves as a circuit for detecting a certain period of time after the engine is started. Furthermore, since the output voltage of the power generating coil 1a changes depending on the rotation of the engine, the time required to obtain the predetermined voltage changes. Therefore, the resistor 7b and capacitor 7c also serve as a circuit for detecting the rotational speed of the engine. Further, the resistor 7e constitutes a circuit that discharges the charge of the capacitor 7c for a certain period of time after the engine is stopped. The Zener diode 7d keeps the discharge time constant by regulating the terminal voltage of the capacitor 7c. This engine operating state detection means 7 outputs the predetermined voltage as a predetermined signal when a predetermined period of time has elapsed after the start of the engine or when the number of rotations has reached a predetermined value. Reference numeral 8 denotes a constant voltage power supply circuit which inputs the voltage from the generating coil 1a to create a constant voltage Vcc and supplies it to each part of an ignition timing control circuit (described later) via a terminal 8a.

Reference numeral 9 denotes a transistor that becomes conductive when a predetermined signal is output from the engine operating state detection means 7 and blocks the first ignition signal from the signal coil 1b;
1 is a resistor and a diode through which a negative signal from the signal coil 1b passes, 13 and 12 are resistors and a diode through which a positive signal from the signal coil 1b is passed, and 14 is a throttle valve of the engine. Reference numeral 15 denotes a throttle switch that operates in conjunction with the throttle valve 14, and is composed of a first contact 15a that closes when the throttle valve 14 is fully open, a second contact 15b that closes when the throttle valve 14 is fully closed, and a movable contact 15c. There is. 16 is an ignition timing control circuit having constant angle oscillation circuits 16a and 16b. The ignition timing control circuit 16 calculates the ignition timing based on the negative pulse voltage, which is the advance signal output from the signal coil 1b, and generates a second ignition signal. The second ignition signal is advanced when the throttle switch 15 closes the first contact 15a, and the second ignition signal is advanced when the throttle switch 15 closes the first contact 15a.
When the circuit is closed, the first and second
When both contacts 15a and 15b are open,
The angle is advanced according to the rotation speed of the engine. Further, the ignition timing control circuit 16 also outputs a third ignition signal delayed from the first ignition signal outputted from the signal coil 1b.

Next, the operation will be explained. A voltage is generated in the generator coil 1a of the magnet generator 1 in accordance with the rotation of the engine. The current that flows due to the generation of this voltage is rectified by the diode 2 and charges the capacitor 3.
On the other hand, the positive pulse voltage output from the signal coil 1b as a delayed signal is applied to a diode 12 and a resistor 1.
3 to the gate 6a of the thyristor 6 as a first ignition signal at time _t1 shown in FIG.

At this time, the voltage Vcc from the power supply circuit 8 is applied to the bases 17a, 17'a of the NPN transistors 17, 17' of the ignition timing control circuit 16 through the resistors 18, 18'.
through transistors 17, 17'
becomes ON state. Therefore, the set S terminals of the RS flip-flop circuits (ff circuits) 20, 20' are grounded via the transistors 17, 17', and low level signals are output from the +Q terminals, respectively. This signal is transmitted to the first and second operational amplifiers 22, 22' via resistors 21, 21'.
is input to one terminal of A voltage V 1 obtained by varying the voltage Vcc from the power supply circuit 8 by a circuit not shown is applied to the + terminal of the operational amplifier 22, and a voltage V ₁ obtained by varying the voltage Vcc from the power supply circuit 8 by a circuit not shown is applied to the + terminal of the operational amplifier 22'. A voltage V ₁ ' is applied. Therefore, the outputs of the operational amplifiers 22, 22' become high level. For this reason, capacitors 23, 2
3' is charged to the polarity shown. Further, the output terminals of the operational amplifiers 22, 22' are connected to the -
Since the outputs of the operational amplifiers 22 and 22' are both at high level, a low level signal is sent from the operational amplifiers 25 and 25' to the reset R terminals of the f-f circuits 20 and 20'. is output. Therefore, f-f circuit 2
0 and 20' are not reset, and the output from the +Q terminal remains unchanged. A reference voltage Vr obtained by switching the voltage Vcc from the power supply circuit 8 is applied to the + terminal of the operational amplifier 25. This voltage Vr is
The throttle switch 15 automatically switches as follows. In other words, throttle valve 1
4 is fully open, the movable contact 15c of the throttle switch 15 closes the first contact 15a, and the reference voltage Vr is switched to the lower first level _Vr1 by the resistors 31-34. When the throttle valve 14 is fully open, the movable contact 15c closes the second contact 15b and transfers the reference voltage Vr to the resistor 3.
Switching to a second level Vr ₂ having a higher value from 1 to 34. Further, when the throttle valve 14 is between fully closed and fully open, the movable contact 15c opens both the first and second contacts 15a and 15b, and the reference voltage Vr is adjusted to the first level and the second level. Switch to a level between . Also, operational amplifier 2
A voltage Vr', which is obtained by changing the voltage Vcc from the power supply circuit 8 by a circuit not shown, is applied to the + terminal of the power supply circuit 5'. Further, - of the fifth operational amplifier 26
The terminal is connected to the output terminal of the operational amplifier 22 via a resistor 24, and the + terminal is connected to the +Q terminal of the ff circuit 20 via a resistor 27. moreover,
The output terminal of the operational amplifier 26 is connected to the gate 6a of the thyristor 6 via a capacitor 27 forming a differential circuit. Similarly, op amp 2
The output terminal of 5' is connected to the gate 6a of the thyristor 6 via a capacitor 28 forming a differential circuit. Note that the + terminal of the operational amplifier 26 is grounded via a resistor 29.

Here, when a negative pulse voltage, which is a delayed signal, occurs in the signal coil, the resistor 10 and the diode 1
A current flows through the resistor 10, and a negative voltage is generated across the resistor 10. This negative voltage is used as a signal for setting the ignition timing at the bases 17a and 1 of the transistors 17 and 17' that constitute the ignition timing control circuit 16.
7'a. When a negative voltage is applied to the bases 17a, 17'a, the voltages of the bases 17a, 17'a to the emitters 17b, 17'b are made negative, so that only the duration of the negative pulse voltage width of the signal coil 1b is applied. Transistors 17 and 17' are turned off. Therefore, from the power supply circuit 8, the resistor 19,1
A positive voltage is applied to the S terminal of the f-f circuit 20, 20' through the terminal 9', and the +Q of the f-f circuit 20, 20'
The output from the terminal turns to high level. This high level signal is input to the - terminals of operational amplifiers 22, 22' via resistors 21, 21'. f-f
The high level signal from the circuit 20 is also input to the + terminal of the operational amplifier 26. Therefore, the outputs of the operational amplifiers 22, 22' turn to low level.
As a result, the charge on the capacitor 23 is reduced to the resistor 2
1. Discharge begins with a fixed time constant determined by the value of the + terminal voltage V ₁ of the capacitor 23 and operational amplifier 22. Similarly, the charge in the capacitor 23' begins to discharge at a constant time constant determined by the value of the +voltage V' ₁ of the resistor 21', the capacitor 23', and the operational amplifier 22'. As a result, the potentials at points _A1 and _A2 shown in FIG. 1, that is, the negative terminal voltages V _A1 and V _A2 of the operational amplifiers 25 and 25', are distributed at a constant level as shown by the solid lines in FIG. gradually decreases.
Further, the input voltage to the - terminal of the operational amplifier 26 also begins to decrease. Then, when the input voltage to the negative terminal of the operational amplifier 26 falls below the positive terminal voltage _V5 , a high level signal is output from the output terminal of the operational amplifier 26. This signal is differentiated by a capacitor 27 and applied to the gate 6a of the thyristor 6 as a second ignition signal at time _t5 shown in FIG. Further, when the voltage V _A1 at the _A1 point decreases and becomes smaller than the reference voltage Vr applied to the + terminal of the operational amplifier 25, the output of the operational amplifier 25 becomes high level. This high level signal is the f-f circuit 2
Since it is applied to the R terminal of 0, the output from the +Q terminal of the ff circuit 20 changes to low level. As a result, the output of the operational amplifier 21 turns to high level, and the capacitor 23 is gradually charged.
A ₁ -point voltage V _A1 is at time t ₃ as shown by the solid line in Figure 3.
It gradually increases with a more constant public distribution.

Also, the negative terminal voltage V _A2 of the operational amplifier 25' is +
When the terminal voltage drops below V′r, the operational amplifier 25′
A high level signal is output from. This signal is differentiated by a capacitor 28 and is then differentiated by a thyristor 6.
At the time t ₂ shown in FIG.
applied as an ignition signal. At the same time, the high level signal is applied to the R terminal of the ff circuit 20', so the output from the +Q terminal of the ff circuit 20' changes to low level. This results in
Since the output of the operational amplifier 22' changes to a high level, the capacitor 23' is gradually charged, and the _A2 point voltage V _A2 gradually increases with a constant distribution as shown by the solid line in FIG. The above operation is repeated every time a negative pulse voltage is output from the signal coil 1b.

The engine operating state detecting means 7 outputs a predetermined voltage as a predetermined signal to the base 9a of the transistor 9 when a predetermined period of time has elapsed after the start of the engine or when the rotational speed reaches a predetermined value. When the predetermined voltage is applied to the base 9a of the transistor 9, the transistor 9 becomes conductive and thereafter short-circuits the positive pulse voltage output from the signal coil 1b.
This prevents the first ignition signal from being applied to the gate 6a of the thyristor 6.

Next, the method and timing of generating the first, second, and third ignition signals will be explained with reference to FIG. In FIG. 3, the horizontal axis represents the rotation angle, and the vertical axis represents the potential, and the operation at one point A in FIG. ₁ is shown in the upper half, and the operation at _two points A in the lower half. In the figure, at time _t0 , a negative pulse voltage, which is a leading signal, is output from the signal coil 1b, and at time _t1
Assume that a positive pulse voltage, which is a delayed signal, is output at . At this time, the positive pulse voltage output at time _t1 becomes the first ignition signal. On the other hand, when the negative pulse voltage is applied to the transistor 17,
When applied to the bases 17a and 17'a of 17',
In FIG. ₁ , the voltage V _A1 at point A1 and the voltage V _A2 at _two points A gradually decrease with a constant distribution, as shown by the solid lines.

Then, at time t ₅ when the voltage V _A1 becomes smaller than the + terminal voltage V ₅ of the operational amplifier 26, the operational amplifier 26 outputs a high-level signal. This high level signal is differentiated by the capacitor 27 in FIG. 1 and becomes the second ignition signal. From time _t3 when the voltage V _A1 further decreases and becomes smaller than the positive terminal voltage Vr of the operational amplifier 25, it starts to rise at a constant distribution as described above. On the other hand, at time _t2 when the voltage V _A2 becomes smaller than the + terminal voltage V'r of the operational amplifier 25', the operational amplifier 25' outputs a high level signal. This high level signal is differentiated by the capacitor 28 in FIG. 1 and becomes the third ignition signal. At the same time, the voltage V _A2 starts to rise with a constant distribution. Signal coil 1b at time t ₄
When a negative pulse voltage is output from , the above operation is repeated.

The first to third ignition signals described above are applied to the gate 6a of the thyristor 6, but the charge in the capacitor 3 is discharged only by the temporally earliest signal among these three ignition signals.

The operations described above from time t ₀ to t ₄ occur while the magnet generator 1 is making one rotation (360° rotation). Furthermore, since the distributions of the voltages V _A1 and V _A2 that change as the capacitors 23 and 23' are charged and discharged are constant, (t ₃ - t ₀ )/(t ₄ - t ₀ ) and ( t ₂ −t ₀ )/(t ₄ −t ₀ ) are each constant. Therefore, even if the rotational speed of the engine changes, the time t ₀
and t ₃ and the angular difference corresponding to t ₀ and t ₂ will be kept constant. Next, a method of advancing the second ignition signal will be described. Assume that the engine is now rotating at a rotation speed lower than the rotation speed _n1 shown in FIG. At this time, the throttle valve 14 is fully opened, and the movable contact 1 of the throttle switch 15 is
5c closes the first contact 15a, thereby reducing the voltage Vr to the first level Vr ₁ .
At this time, V _A1 also decreases to V′ _A1 , but V _A1
Since the public distribution of V′ _A1 is equal, triangles abc and a′b′c′ are congruent, and the angular position at time t ₃ remains unchanged. In this way, when V _A1 decreases to V' _A1 , the time at which V' _A1 crosses the + terminal voltage V ₅ of the operational amplifier 26 shifts to t ₆ , and the second ignition signal changes from t ₅ to t ₆ It will advance to . As the engine speed increases and the time required for one revolution (360° rotation) becomes shorter, the charging voltage of the capacitor 23 becomes smaller. Therefore,
The voltage V′ _A1 at times t ₀ and t ₄ becomes smaller and smaller, and the second ignition signal becomes further advanced than at t ₆ . When the rotational speed of the engine becomes around _n1 , the voltage _V'A1 at times _t0 and _t4 further decreases to become smaller than the voltage _V5 . Therefore,
The voltage V ₅ is applied to the + terminal of the operational amplifier 26, that is, the negative pulse voltage from the signal coil 1b is applied to the base 17a of the transistor 17 via the resistor 10, that is, at t ₀ , the operational amplifier 26 The output becomes high level, and the second
The ignition signal is at the maximum advance angle (in this example
BTDC25°).

The above operation is performed in an extremely short time, and the ignition timing is immediately advanced to the maximum. Therefore, the output of the engine increases instantaneously, resulting in improved acceleration.

Conversely, when the engine is rotating at a high speed of more than _n2 shown in FIG.
Suppose that it is fully closed. At this time, the movable contact 15c of the throttle switch 15 closes the second contact 15b, and the voltage Vr rises to the second level, _Vr2 .
At this time, V _A1 also rises to V″ _A1 , but V _A1
Since the public distributions of V″ _A1 are equal, triangles abc and a″b″c″ are congruent, and the angular position at time _t3 remains unchanged. Thus, when V _A1 rises to V″ _A1 , V″ _A1 increases at time t ₇
The second ignition signal differs from the terminal voltage _V5 of the operational amplifier 26, and the second ignition signal is largely delayed from _t0 to _t7 . Then, as the engine speed decreases, the voltage _V''A1 at times _t0 and _t4 becomes larger and larger, and the second ignition signal is further retarded than at _t7 .

Since the above operations are performed in a very short time,
Ignition timing is rapidly retarded. Therefore, the output of the engine is rapidly reduced and deceleration performance is improved.
Further, in this case, the ignition timing will not be advanced unless the engine rotates at an extremely high speed.

Further, when the throttle valve 14 is operated within a range between fully open and fully closed, both the first and second contacts of the throttle switch 15 are opened. In this case, the voltage Vr is held at a level between the first level voltage Vr ₁ and the second level Vr ₂ , and the ignition timing is advanced in accordance with the rotation speed of the earlier engine.

FIG. 4 is a diagram showing the advance characteristic of the ignition timing with respect to the engine speed. In the figure, B characteristic is the advance angle characteristic when starting the engine, C characteristic is when the throttle valve 14 is fully open, D characteristic is E when the throttle valve 14 is between fully closed and fully open.
The characteristics show the lead angle characteristics when fully closed. When the engine is started, it is started by the first ignition signal generated at time _t1 , but after a certain period of time has elapsed after the engine is started, the engine rotational speed is increased.
For example, when n ₀ is reached, the transistor 9 shown in FIG.
After this, the first ignition signal no longer contributes to ignition, and the engine is ignited by the third ignition signal generated at time _t2 . This is shown in characteristic B. When the engine speed is n ₁ (idle state) and the throttle valve 14 is fully opened, the second ignition signal reaches the t ₀ position, the ignition timing is advanced to the maximum, and rapid acceleration occurs. This is shown in characteristic C. When the throttle valve 14 is not fully closed or fully open,
The ignition angle is advanced along the D characteristic shown in FIG. 4 in accordance with the engine speed, and when the throttle valve 14 is fully opened, the E characteristic is adopted, and the second ignition signal is rapidly retarded. At this time, since the engine is ignited by the third ignition signal at time _t2 , the rotation of the engine rapidly decreases. This third ignition signal is generated at the time t ₁ (in this embodiment) when the first ignition signal occurs.
BTDC5°) later than time t ₂ (in this example
ATDC5°), the output of the engine when ignited with this third ignition signal is lower than the output when ignited with the first ignition signal, making the idle speed lower and stable. can be rotated. In other words, the stable rotation range becomes larger. Note that by making the voltage of the power supply 30 that generates V' ₁ of the operational amplifier 22' variable, the time t ₂ can be adjusted and the idle rotation speed can be adjusted.

As described above, in this embodiment, the SILSTAR 6 supplies engine ignition power to the ignition coil 4 of the engine, and the positive and negative pulse voltages for setting the ignition timing of the engine according to the rotation of the engine. A signal coil 1b is connected to a signal coil 1b for applying a positive pulse voltage, which is a delayed signal of the positive and negative pulse voltages, to the thyristor 6 as a first ignition signal, and a throttle valve 14 of the engine. a first contact 15a that closes when the valve 14 is fully open;
A throttle switch 15 is provided which has a second contact 15b that is closed when the throttle is fully closed, and the ignition timing is controlled by a constant angle oscillation circuit 16a based on the negative pulse voltage that is the leading signal among the positive and negative pulse voltages. The calculation is performed to generate a second ignition signal, and when the throttle switch 15 closes the first contact 15a, the second ignition signal is rapidly advanced; When the second contact 15b is closed, the angle is rapidly retarded, and when both the first and second contacts 15a and 15b are open, the angle is advanced in accordance with the engine speed. Therefore, it is possible to obtain an ignition timing control device that improves the deceleration, startability, and acceleration of the engine, and has high durability and reliability.

Further, a third ignition signal delayed from the first ignition signal is generated by the constant angle oscillation circuit 16b, and a predetermined signal is output when a certain period of time has elapsed after the engine start or when the rotation speed reaches a predetermined value. A transistor 9 is provided as a cut-off means which is activated by a predetermined voltage output as a predetermined signal from the engine operating state detecting means 7. Since the first ignition signal of the engine is cut off and the third ignition signal delayed from the first ignition signal is applied to the thyristor 6 for ignition, the idle speed of the engine is changed to the lower than when ignited by the first ignition signal,
It is possible to provide an ignition timing control device that expands the rotation range of the engine and improves stability.

Furthermore, in this embodiment, since the magnet generator 1 is completely fixed to the crankcase (not shown) of the engine, the durability of the device against vibrations of the engine is improved.
Reliability has further improved.

Next, another embodiment of the present invention will be described with reference to FIGS. 5 and 6. FIG. 5 is a circuit diagram of an ignition timing control device according to another embodiment of the present invention;
FIG. 6 is an ignition timing advance characteristic diagram. In FIG. 5, 16 is an ignition timing control circuit having a constant angle oscillation circuit 16a. The output terminal of the operational amplifier 25 is connected to the R terminal of the ff circuit 20, and is also connected to the gate 6a of the thyristor 6 via a capacitor 35 forming a differential circuit. The other configuration is the constant angle oscillation circuit 1 shown in FIG.
The structure is the same as that shown in FIG. 1 except that 6b is not provided, and the explanation thereof will be omitted.

Next, the operation will be explained. A positive pulse voltage, which is a delayed signal from the signal coil 1b, is applied to the gate 6a of the thyristor 6 as a first ignition signal. At this time, the capacitor 23 is charged to the illustrated polarity, and the voltage A _A1 at point A rises in the same manner as described in the embodiment of the present invention.

Here, when a negative pulse voltage from the signal coil 1b is applied to the base 17a of the transistor 17, the capacitor 23 starts discharging, and the voltage V _A1 starts to decrease at a constant distribution. And op amp 2
When the voltage becomes smaller than the voltage V ₅ applied to the + terminal of 6, the operational amplifier 26 outputs a high level signal. This high level signal is connected to capacitor 27.
The second ignition signal is then differentiated by . When V _A1 further decreases and becomes smaller than the reference voltage Vr applied to the + terminal of the operational amplifier 25, the operational amplifier 25 outputs a high level signal. This high level signal is differentiated by a capacitor 35 and becomes a third ignition signal. Since this high level signal is also applied to the R terminal of the f-f circuit 20, the voltage V _A1 starts to rise again at a constant distribution from this time.

The method of advancing the second ignition signal is the same as that of the embodiment of the present invention described above, so its explanation will be omitted. Furthermore, it goes without saying that the thyristor 6 operates with a temporally faster signal among the first, second, and third ignition signals.

FIG. 6 shows the advance characteristics of the ignition timing. The B, C, D, and E characteristics shown in this figure correspond to the B, C, D, and E characteristics shown in FIG. 4, respectively. From the D characteristic in this figure, it can be seen that the angle is rapidly advanced at the rotation speed _n3 . Further, from the E characteristic, it can be seen that when the throttle valve 14 is fully opened, the ignition timing is retarded to the maximum. Other characteristics are the same as shown in FIG.
The explanation will be omitted.

〔Effect of the invention〕

As described above, in this invention, the delayed side signal from the signal generating means is used as the first ignition signal, and
An ignition timing control circuit generates a second ignition signal and a third ignition signal delayed from the first ignition signal based on the advance signal, and when the throttle valve is fully open, the second ignition signal By advancing the ignition signal and retarding the second ignition signal when the throttle valve is fully closed, acceleration and deceleration of the engine are improved, and the engine is maintained at a predetermined rotation speed. When rotating at low speed,
Since the engine is ignited by the third ignition signal, the rotational speed of the engine is lowered than when the engine is ignited by the first ignition signal, and the stability is improved, so that the engine can operate stably. It is possible to provide an ignition timing control device that expands the rotation range.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an ignition timing control device according to an embodiment of the present invention, FIG. 2 is a configuration diagram of a magnet generator,
FIG. 3 is a diagram showing changes in signals in the main parts of the ignition timing control device shown in FIG. FIG. 6 is a circuit diagram of an ignition timing control device according to another embodiment of the present invention, and is an ignition timing advance characteristic diagram by the ignition timing control device shown in FIG. In the figure, 1... Magnet generator, 1a... Ignition power source, 1b... Signal generation means, 4... Ignition coil,
6... Switching element, 7... Engine operating state detection means, 14... Throttle valve, 15... Throttle switch, 16... Ignition timing control circuit. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. An ignition power source that generates voltage according to the rotation of the engine and supplies the power necessary for ignition of the engine, and an ignition power source that supplies power from the ignition power source to the ignition coil of the engine at a predetermined time. a switching element that supplies or cuts off the ignition timing, generates positive and negative signals for setting ignition timing according to the rotation of the engine, and applies a delayed signal of the positive and negative signals to the switching element as a first ignition signal; a signal generating means for outputting a predetermined signal when a predetermined period of time has elapsed after the start of the engine or when the number of revolutions has reached a predetermined value; A throttle switch having a first contact that is closed when the valve is fully open and a second contact that is closed when the valve is fully closed; When the throttle switch closes the first contact, the engine is advanced regardless of the engine speed, and when the throttle switch closes the second contact, the engine is advanced regardless of the engine speed. on the retard side,
When both the first and second contacts are open, a second ignition signal is generated at a position corresponding to the rotational speed of the engine, and a third ignition signal delayed from the first ignition signal is generated. An ignition timing control device comprising: an ignition timing control circuit that outputs an ignition timing control circuit; and a cutoff means that cuts off the first ignition signal to the switching element when a predetermined signal from the engine operating state detection means is output. . 2. The ignition timing control device according to claim 1, wherein the ignition power source is constituted by a generator coil that generates an alternating current voltage according to the rotation of the engine. 3. The ignition timing control device according to claim 1, wherein the signal generating means is constituted by a signal coil that generates positive and negative pulse voltages in accordance with the rotation of the engine. 4. The ignition timing control device according to claim 1, wherein the switching element is constituted by a thyristor. 5. The ignition timing control device according to claim 1, wherein the cutoff means is constituted by a transistor.