KR840000684B1 - Control circuit of ignion timing for internal combustion engine - Google Patents

Abstract

An ignition timing control system for an internal combustion engine has a circuit to generate a reference ignition signal synchronously with the engine, a circuit to generate a reatard ignition signal at a point shifted by a selected shaft angle of the engine from the reference ignition signal, and an ignition circuit to control the ignition timing of the engine according to the retard ignition signal.

Description

Internal combustion engine ignition timing control circuit

1 is a one embodiment circuit diagram of an ignition timing control circuit of the present invention.

2 is an operation waveform diagram of an essential part of a circuit for explaining the operation of the circuit of FIG.

3A, 3B and 4 are waveform diagrams for explaining the operation characteristics of the output transistor of the ignition circuit.

5 is a circuit diagram showing one implementation of the current time limit short circuit.

6 is an operation waveform diagram of an essential part of a circuit for explaining the pupil of the circuit shown in FIG.

7 is an operational waveform diagram of an essential part of FIG. 1 for explaining the operation of the delay angle ignition signal generation circuit.

8 is a waveform diagram for explaining the ignition timing control characteristic of this embodiment.

9 is a diagram showing the ignition timing control characteristic of this embodiment.

10 is a one embodiment circuit diagram of a switch circuit.

11 is a circuit diagram showing another embodiment for changing the charging current to the capacitor.

The present invention relates to an internal combustion engine ignition timing control circuit, and more particularly, to an ignition timing control circuit for generating a lag angle ignition signal.

In general, the internal combustion engine ignition timing control circuit is designed to ignite at a point that is delayed by an angle from the lead angle position at which the engine exhibits the maximum output in order to suppress the generation of nitrogen oxides from the viewpoint of pollution prevention by automobiles. have. Conventionally, a monostable multivibrator is used as a circuit for generating such a delay angle ignition signal. For example, Japanese Patent Application No. 74-46012, filed with a patent application in Japan on September 28, 1970, and filed on December 7, 1974, is for charging a capacitor for giving an unstable time for a monostable multivibrator. There is a constant current circuit and a constant current circuit for discharging, but these two constant current circuits are configured to alternately charge or discharge capacitors, and the ignition signal is output as late as the unstable time of the monostable multivibrator. In the conventional apparatus, the reference ignition signal obtained in synchronization with the rotation of the distributor is shaped into a spherical pulse, and the rear end of the pulse becomes the reference ignition point and is delayed by the delay angle ignition signal generation circuit at this reference ignition point. Each ignition pulse is generated. In addition, in the non-contact type ignition device, the output transistor of the ignition circuit is turned on a little before the ignition timing, and is configured to ignite by cutting off the output transistor at the ignition timing. In case of delaying the ignition timing, the delayed ignition signal is output from the point of occurrence of the reference ignition signal by removing the reference ignition signal from the delay angle ignition signal before the rear end of the reference ignition signal acts on the output transistor. Configured to delay as long as possible. For this reason, if the time for making the delay angle ignition signal is too long, the reference ignition signal first acts on the output transistor, and a material that ignites before the desired delay angle ignition point is generated.

Delay angle of the reference ignition signal Input to the ignition signal generating circuit and delay angle ignition signal generating circuit In the reference ignition control circuit, this output is performed between one to several transistors in the transmission path of the reference ignition signal, but delayed. In order to form the delay angle ignition signal in each ignition signal generating circuit, signal transmission must be performed through more transistors. Therefore, the delay of the operation time of the transistor is duplicated and the delay ignition signal is delayed than the reference ignition signal. In order to make the ignition signal generating circuit smaller, the capacitor, diode, or even the resistor can be formed by using an integrated circuit using transistors. Appears.

It is an object of the present invention to provide an ignition timing control circuit of an internal combustion engine which prevents the ignition by the reference ignition signal when the ignition timing of the engine is controlled by the delay angle ignition signal.

The present invention is characterized in that the reference ignition signal is connected between the reference ignition signal input circuit connection point to the delay angle ignition signal generation circuit connected in the middle of the reference ignition signal transmission path and the output ignition signal connection point from the delay angle ignition signal generation circuit. The present invention provides a stable ignition timing control characteristic by forming a delay circuit for delaying transmission and eliminating the malfunction in which the ignition circuit is biased by the reference ignition signal when the delay angle ignition signal invention circuit is operating.

Hereinafter, the present invention will be described in detail with reference to the embodiment shown in the drawings.

In Fig. 1, the ignition timing control circuit with the delay angle ignition signal generation circuit of the present embodiment is composed of 1 to 11 parts divided by dotted lines, and the parts of 1 to 5 are reference ignition control circuits (A). 7 to 11 constitute delay angle ignition signal generation circuits B, respectively.

1 is a reference ignition signal generating circuit, and 2 is a signal amplifying circuit which waveform-forms a signal generated by the reference ignition signal generating circuit 1. The waveform-shaped signal in the amplifying circuit 2 is applied to the ignition circuit 3 to operate the ignition circuit 3 so as to abruptly block the primary current which is black in the ignition coil C, thereby ignition coil C Sparks are generated in the spark plug G at the high voltage induced on the secondary side of the. 4 is a current limiting circuit for limiting the black current on the primary side of the ignition coil, so that a current above the current sufficient for ignition does not flow to the primary side circuit.

5 is a current limiting time shortening circuit which operates simultaneously with the operation of the current limiting circuit 4 to control the impact of the signal of the signal generating circuit 1 to minimize the time taken for the current limiting.

B is a delay angle ignition signal generating circuit that generates a delay angle ignition signal from the reference ignition signal and replaces it with the reference ignition signal to give the delay angle ignition signal to the ignition circuit. The delay angle ignition signal generating circuit B is composed of 7 to 11 portions. 7 is a trigger generation circuit for generating a trigger signal by receiving the main ignition signal, 8 is a bistable multivibrator driven in one direction by a trigger signal from the trigger generation circuit 7, and 9 is a constant current charge / discharge circuit of the capacitor Q. The triangular wave forming circuit 10, which detects the discharge voltage of the capacitor Q, inverts the bistable multivibrator 8 when the voltage drops to a predetermined value, and provides a delay angle ignition signal to the ignition circuit 3 at the same time. A comparator CMP is included as an output circuit to be provided. 11 is a switching circuit for connecting or disconnecting the delay angle ignition signal generating circuit B to or from the reference ignition circuit A. When the delay angle ignition signal is not required, the trigger signal input to the bistable multivibrator 8 is inputted. At the same time as the ground, it has a function of releasing the charge accumulated in the capacitor Q to the ground.

The circuit shown by the dashed-dotted line in FIG. 1 (indicated by the symbol MIC) is formed as a single chip by the monolithic IC. This chip is mounted on a resistor printed substrate together with a capacitor chip not included in the MIC, and the substrate is bonded to the heat sink on which the chip of the output transistor is attached by bonding or the like to electrically connect the devices on the substrate and the chip of the output transistor. It is connected and configured as one ignition circuit module.

Hereinafter, each part of the ignition control circuit of the internal combustion engine will be described in more detail.

Reference ignition signal generating circuit (1)

The reference ignition signal generating circuit 1 includes a pickup coil 100 that links to a closed furnace formed in the distributor.

The shaft of the distributor is configured to change the magnetic flux in the waste furnace by the number of times equal to the number of cylinders of the engine between the rotation of the engine and the rotation of the shaft one rotation, that is, between two revolutions of the engine's crankshaft. As a result of the change, an AC voltage as shown in FIG. 2 (a) is generated between the terminals of the pickup coil 100.

One end of the pickup coil 100 is connected to the positive electrode of the power supply via the resistor 101 and grounded via a diode 102 connected forward to the power supply. This diode 102 is for temperature compensation of the transistor T ₁ . Since the diode 103 connected in the reverse direction to the power source is connected in parallel to the diode 102, the reverse voltage applied to the diode 102 is bypassed. The other end of the pickup coil is connected to the base of the transistor T ₁ via the resistors 104 and 105. A capacitor 106 for noise absorption is connected between the connection point of the resistors 104 and 105 and the ground. On the other hand, the capacitor 105 is connected to the resistor 105 in parallel, and a quick switching signal from the pickup coil 100 is transmitted to the transistor T ₁ through the capacitor 107. The induced voltage of the transistor (T ₁₎ of the base-emitter than the voltage drop across the diode, since 102 is the forward voltage drop is designed to be slightly larger of the transistor (T ₁₎ pick-up coil 100 is applied in a direction opposite to the base of The current flows through the resistor 101, the pick-up coil 100, the resistors 104, and 105 between the base emitters of the transistor T ₁ until the voltage drops to a predetermined value, and the transistor T ₁ is turned on. .

The collector of the transistor T ₁ is connected to the positive electrode of the power supply via a resistor 109, and the emitter is connected to ground via a resistor 110, respectively. The diode 108 connected in the reverse direction between the base of the transistor T ₁ and ground prevents the reverse voltage from being applied between the base emitter of the transistor T ₁ .

The operation of the main ignition signal generation circuit 1 configured in this manner will be described.

When the induced voltage of the pickup coil 100 is generated at the polarity of the diode 102 side to be negative and drops to the voltage indicated by the point b of FIG. 2 (a), the base of the transistor T ₁ is biased in the reverse direction. The transistor T ₁ is turned off because the voltage to be increased. The induced voltage of the pick-up coil 100 increases in the negative direction again, but when the point C reaches point C, the polarity is reversed rapidly and reaches point e rapidly, so that the resistance 104 becomes the positive electrode. Inversion of the polarity is rapid and the forward bias of the transistor again (T ₁₎ when only the voltage rise occurs in the instantaneous point d to recover from the operation level of the transistor (T ₁₎ is ON and the transistor (T _1). Therefore, the transistor T ₁ is turned off while the terminal voltage of the pick-up coil changes from point b to point d, and is turned on from point d to the next waveform b '. This state is shown in FIG. 2 (b) as a change in the collector potential of the transistor T ₁ .

A transistor (T ₁₎ that when OFF, so the circuit configuration, the output transistor of the ignition circuit (3) so as to ON transistor (T ₁₎ that while the OFF That is, the voltage of the pickup coil 100 at the point b to the point d During the change, the output transistor is ON, so when the point d reaches, the transistor T ₁ is turned on at the same time. On the contrary, the output transistor is turned OFF to cut off the primary current of the ignition coil to generate an ignition voltage in the secondary coil.

Amplifier circuit (2)

An amplifier circuit for amplifying the reference ignition signal (2) is provided with a transistor (T ₂₎ the base is connected through a resistor 201 to the collector of the transistor (T _1). A transistor (T ₂₎ of the ground through the emitter of the transistor (T ₁₎ with a common emitter resistor 110, a transistor (T _1), and and (T ₂₎ constituting the Simi bit circuits at the transistor (T ₂₎ The collector is connected to the positive electrode of the power supply via the resistor 202.

The base of the amplifying transistor T ₃ is connected to the collector of the transistor T ₂ , the collector is connected to the positive electrode of the power supply via a resistor 203, and the emitter is directly connected to ground respectively. A transistor (T ₃₎ transistors the collector is via a converter (電路) a diode (204) connected at the same time in the forward direction as soon (ℓ ₁₎ is connected for passing liquor screen signal to a delay signal generating furnace (B) (T ₄₎ It is connected to the base of.

The collector of the transistor T ₄ is connected to the positive electrode of the power supply via the resistor 205, the emitter is connected to the direct ground, respectively, and the capacitor 206 is connected between the base collectors. The capacitor 206 is a capacitor of about 10 to 30 picofarads using a capacitance formed between the P layer and the N layer of the monolithic (IC) and constitutes a Miller integrator together with the diode 204. And delays the turn-off time of transistor T ₄ by several microseconds. Transistor to the ground (T ₄₎ of the collector is a collector of the transistor (T ₅₎ Since the base connection of the transistor (T ₅₎ is connected to the positive electrode of the power source via the resistor 207 and via an emitter resistor 208 Each is connected. In the transistor (T ₅₎ emitter transistor (T ₆₎ of is connected to the base, the transistor (T ₆₎ of the collector via a resistor 209 attached to the outside is connected to the positive electrode of the power source, and an emitter grounded directly to the Are connected to each. And the transistor (T ₅₎ of the base, the delay and the respective ignition signal input with me (ℓ ₂₎ of the signal generating circuit (B) connected, and a transistor (T ₅₎ of to the base, the current limit time reduction circuit 5 the input signal converter (ℓ ₃₎ is connected, respectively.

The amplifying circuit 2 configured in this manner operates as follows.

Since the collector potential when the transistor (T ₁₎ ON is made uniform and the potential of the emitter of the transistor (T ₂₎ transistor (T ₂₎ is OFF, the current does not flow between the base emitter. It is. If by the output voltage of the pickup coil 100, the transistor (T ₁₎ is a cut-off transistor is a collector potential of (T ₁₎ up the current flows between the base emitter of the transistor (T ₂₎ transistor (T ₂₎ is ON . Since the transistors T ₁ and T ₂ form a short circuit, this operation is performed in a very short time. The ON state of the transistor T ₂ continues until the transistor T ₁ is turned ON again by the output signal of the pick-up coil, that is, to the reference ignition signal generation point. The state of this operation is shown in FIG. 2C as a change in the collector potential of the transistor T ₂ .

The operation signal but transmitted to the back transistor (T ₃₎ occurs each ignition signal delay through a second converter (ℓ ₁₎ is said a transistor (T ₄₎ is amplified and inverted through the diode 204 in the circuit (B) the state Is shown as a change in the collector potential of the transistor T ₃ in FIG. The transistor (T ₃₎ is turned OFF, the collector to the high potential when the resistor 203, a diode 204, a current flows to the base-emitter of the transistor (T ₄₎ via the transistor (T ₄₎ is ON. At this time, the current through the diode 204 is bypassed to the capacitor 206 to charge the capacitor 206 to the polarity of the drawing. Therefore, even if the transistor T ₃ is turned on next and the collector potential is lowered to the ground potential, the transistor T ₄ is discharged while the charge accumulated in the capacitor 206 is discharged through the base emitter of the transistor T ₄ . The transistor T ₄ does not turn off immediately because it remains ON. This state is shown in FIG. 2 (d) and FIG. 2 (e) as a change in the collector potential of the transistor T ₃ and a change in the collector potential of the transistor T ₄ . As shown in FIG. 2 (e), the transistor T ₄ is cut off by a delay of time τ ₁ at the time of switching from the OFF to the ON state of the transistor T ₃ , and this time τ ₁ is several microseconds. to be.

The transistor (T ₄₎ when the transistor (T _5), the current flows to the base and emitter resistor 208 of the transistor (T ₅₎ via the resistor (205) is OFF ON. This state is shown in FIG. 2 (f) as a change in the collector potential of the transistor T ₅ . And the resistance 207, the transistor (T _5), a portion of current flowing through the meter and a resistor 208 to the collector transistor (T ₆₎ ON simultaneously with the transistor (T ₆ of the base emitter flows to the emitter transistor (T ₅₎ of the ) Turns on. As a result, the current flowing through the resistors 201 and 210 to the ignition circuit 3 in the rear stage flows to ground through the collector emitter of the transistor T ₆ , and the output transistor in the ignition circuit is cut off. . Therefore, the actual reference ignition timing when there is no delay angle ignition signal is after τ ₁ time after the voltage of the pickup coil reaches point d in the second (a) degree.

The area of each ignition signal generating circuit (B) is based on lighting control when connected to the circuit (A) the transistor (T ₃₎ OFF and at the same time, the converter when the reference ignition signal input from the (ℓ ₁₎ of claim 2 (g) As shown in the figure, a soft ignition signal having a time width T ₃ delayed by a time τ ₂ is outputted and applied to the base of the transistor T ₅ through the converter L ₂ . At this time, the delay time τ ₁ of the cutoff of the transistor T ₄ produced by the Miller integrating circuit is obtained when the delay angle ignition signal is output to the base of the transistor T ₅ after the transistor T ₃ is turned on. It is set larger than the delay time T ₂ until. The delay angle ignition signal acts to lower the base of the transistor T ₅ to ground potential through the converter l ₂ . Therefore, even when the transistor T ₄ is turned off, the base potential of the transistor T ₅ is not immediately raised, and the ground potential human body is held to the rear end of the delay angle ignition signal. As a result, when the delay angle ignition signal is output, the transistor T ₃ is turned on and then delayed by the time (τ ₂ + τ ₃ ) to the rear end of the delay angle ignition signal, so that the output transistor of the ignition circuit 3 is cut off. The ignition timing is delayed by θ ₁ = (τ ₂ + τ ₃ τ ₁ ) rather than the main test timing, and the ignition circuit may operate in the reference ignition signal in the second (h) and second (i) degrees, respectively. The change in the collector potential of the output transistor at the time and the change in the collector potential of the output transistor when the ignition circuit is operated in the delay angle ignition signal are shown.

Ignition Circuit (3)

The ignition circuit 3 has an output transistor circuit configured as two transistors T ₇ and T _{8 that} are connected to Arlington. The base of transistor T ₇ is connected to the collector of transistor T ₆ via a resistor 210, the collector of which is connected to the collector of transistor T ₈ , and the emitter is respectively connected to the base of transistor T ₈ . Connected. In the transistor T ₈ , the collector is connected to the positive electrode of the power supply via the primary winding C ₁ of the ignition coil C, and the emitter is connected to the ground via the resistor 301, respectively. The diode 305 is connected in the reverse direction between the collector and the ground. Between the base emitter of the transistor T ₇ and between the base emitter of the transistor T ₈ are connected to the resistors 302 and 303, respectively, and a zener diode 304 is connected between the collector bases of the transistor T ₈ . It is connected so that an inner node may come to the side, and it is connected so that a cathode may come to the base side.

The operation of the ignition circuit 3 will be described.

When the transistor T ₆ is turned on by the arrival of the reference ignition signal or the delay angle ignition signal, the current flowing through the resistors 209 and 210 to the base of the transistor T ₇ does not flow until the transistor T 6 is turned on. ₇ ) is OFF. A transistor (T ₇₎ transistor (T ₈₎ to the current flowing through the meter to the collector which was the base current is also simultaneously turned OFF, the transistor (T ₈₎ 1 primary winding of the ignition coil (C) through the collector-emitter to the time of (C ₁ ) The current flowing in ₁ ) is cut off, and high voltage is induced in the secondary winding C ₂ of the ignition coil C. This is because of the sharp rise due to the flyback voltage of the ignition coil (C).

This state is explained with reference to FIG.

FIG. 3A shows a time variation of the primary winding current Ic, and FIG. 3B is an enlarged waveform diagram of the time variation of the collector potential Vce of the transistor T ₈ , respectively. When the primary winding current is interrupted at the point of t ₀ , the current decreases with a constant slope due to the turn-off characteristic as shown by a to c of FIG. 3a, but the collector potential of the transistor T ₈ is as shown in FIG. 3b. In the same manner, the voltage is rapidly increased at the portion (a) immediately after the primary winding current is cut off, and rises to the break over voltage Vz of the zener diode 304. Brake OY member jeonapneun transistor of the Zener diode _{(304) (T 7),} (T 8) , because the are below the brake OY member voltage between the collector emitter teoteo transistor _{(T 7), (T 8} ) above, the zener diode ( 304) GABRIELE by Lake OY member Zener current (Iz) flowing through the jaeneo diode As a result the flow through the base-emitter circuit of the transistor (T ₈₎ As a result transistor (T ₈₎ of the collector flows to the collector electrical current (Ic) .

The collector current Ic is amplified by the current amplification of the zener current Iz flowing through the base and the transistor T ₈ by (h _fes ).

I _c = h _{fe8I zc}

Will appear.

The collector current Ic suppresses the increase in the impedance between the collector emitters of the transistor T ₈ , and the collector potential is maintained at the brake overvoltage Vz. The current Iz is about 10 milliamps and the current amplification factor h _fes is about 50 times, so the collector current flows about 500 milliamps. The potential of the transistor T ₈ is forcibly lowered by the collector current Ic as shown by b in FIG. 3B, but the collector current is small, and thus the zener diode 304 does not reach the cut off. The zener diode 304 does not cut off until the primary winding current itself is sufficiently lowered so that the collector potential of the transistor T ₈ is equal to or lower than the zener voltage. In this manner, as shown by b in FIG. 3B, the collector potential of the transistor T ₈ is ramped to the brake over voltage Vz of the zener diode 304.

When the primary winding current decreases again and reaches c of FIG. 3a, the collector potential is equal to or less than the brake over voltage Vz of the zener diode 304, as shown by c of FIG. 3b, and the zener diode 304 is cut off. . After that, the collector potential decreases with decreasing current, but as shown by c to e in FIGS. 3a and 3b, even if the current is zero, the collector potential is not immediately zero, but attenuates while vibrating and finally settles to the ground potential. . This happens several tens of microseconds after the primary winding current is interrupted.

FIG. 4 is a diagram showing a relationship other than the change in the primary winding current Ic and the change in the collector potential of the transistor T ₈ at this time. FIG. 3A and FIG. The same a-e symbols and arrows indicate the change areas of the characteristics.

The diode 305 bypasses this voltage when the high voltage on the secondary winding side of the ignition coil is applied in the opposite direction between the emitter collectors of the transistor T ₈ by the ignition miss, thereby preventing destruction of the transistor T ₈ . do. The two transistors T ₇ , T ₈ and Zener diode 304 of the above-mentioned Darlington connection are, for example, known as Japanese Laid-Open Patent Publication No. 52-27277, for the transistor in a common N layer. It can be formed as one semiconductor chip in which two P layers and one P layer for zener diodes are formed.

Current limiting circuit (4)

The current limiting circuit 4 has a series connection circuit of resistors 401 and 402 connected in parallel with the resistor 301. The connection point of the resistors 401, 402 is the collector of the transistor (T ₉₎ of is connected to the base, the transistor (T ₉₎ is connected to the collector of the transistor (T ₆₎ are connected to the emitter is grounded . The purpose or configuration of such a current limiting circuit is well known in US Pat. Nos. 3, 605, 713 and the like.

The operation of the current limiting circuit 4 will be described.

When the transistor T ₆ is turned off and the output transistor is turned on, as shown in FIG. 2 (j), the primary winding current does not change stepwise due to the reactance of the primary winding and rises with an inclination. The voltage drop of the resistor 301 does not change with this current and rises with a slope. When the primary winding current reaches about 6 amps, the voltage drop of the resistor 301 reaches a predetermined value so that the potential at the connection point of the resistors 401 and 402 becomes a potential sufficient to turn on the transistor T ₉ . When the transistor T ₉ is turned on, a part of the current supplied to the base of the output transistor through the resistors 209 and 210 flows to the ground through the collector emitter of the transistor T ₉ so that the base current of the output transistor is reduced. As it decreases, the primary winding current does not increase any more, resulting in an almost constant current value of 6 amps. That is, in order to prevent the primary winding current from exceeding a predetermined value, the base current of the output transistor is limited to increase the impedance between the collector emitters of the output transistor to suppress the increase of the current. Therefore, the current supplied from the battery power supply does not exceed 6 amps. In the present embodiment, under various operating conditions of the engine, the primary winding current of 6 amps induces a good spark discharge voltage in the spark plug.

In FIG. 2 (j), the dotted line indicates the interruption time of the primary current by the reference ignition signal, and the solid line indicates the interruption time of the primary current by the delay angular ignition signal.

Current Time Limit Short Circuit (5)

Current time shortening circuit 5, a converter (ℓ ₄₎ by a transistor (T ₈₎ of the connected to the collector and the collector potential detects a change in the collector potential of the transistor (T ₈₎ via a converter (ℓ ₄₎ When it reaches a predetermined value, it operates to change the bias potential so that the OFF time of the transistor T ₁ is shortened.

An example of a concrete circuit is shown in FIG.

The converter L ₄ is connected to the collector of the transistor T ₁₀ via the avalanche diode 501 connected in the reverse direction. The base of the transistor T ₁₀ is connected to the emitter of the transistor T ₅ via a resistor 502 and a converter L ₃ , and the emitter is connected to ground, respectively. Between the collector emitter of transistor T ₁₀ , the series circuits of resistors 503 and 504 are connected in parallel, and the connection point of both resistors is connected to the base of transistor T ₁₁ via diode 505 connected in the forward direction. Is connected to. Both collectors of the transistors T ₁₀ and T ₁₁ are connected to the positive electrode of the power supply via the resistors 506 and 507, respectively. The collector of the transistor T ₁₁ is again connected to the base of the transistor T ₁₂ via a capacitor 508, a diode 509, and a resistor 510, and the emitter of the transistor T ₁₁ is grounded.

The cathode of the diode 511 is connected to the connection point of the capacitor 508 and the anode of the diode 509, and the resistor 512 whose one end is grounded is connected to the anode of the diode 511. The other end of the capacitor 513 whose one end is grounded is connected to the connection point between the cathode of the diode 509 and the resistor 510. The collector T ₁₂ is connected to the positive electrode of the power supply, and the emitter is connected to the base of the transistor 1 via the resistor 514 and the converter L ₅ .

The operation of one circuit of the current time limit short circuit will be described. When the collector current of the output transistor rises due to the current limitation of the collector current due to the action of the current limiting circuit 4 after the output transistor is turned on, the avalanche diode 501 breaks over and breaks the collector of the transistor T ₁₀ . The potential, that is, the potential at the connection point of the resistors 506 and 503 rises. When the output transistor is turned on, the transistor T ₆ is turned off, so the transistor T ₁₀ is also turned off. As a result, the change in the collector potential of the output transistor results in a change in the potential of the connection point between the resistors 506 and 503 described above. As appears directly. The change in the collector potential of the output transistor due to the current limitation is the same as the rise of the collector potential in the primary winding current interruption and is accompanied by a drastic change in a very short time. It happens rapidly in a short time. Rise of the potential of the connection point is resistor 503, is applied to the 504 partial pressure is the voltage of the voltage drop corresponds to the diode transistor (T ₁₁₎ through 505 of the resistance 504, the transistor (T ₁₁₎ is ON do. This state continues until the output transistor is turned off. That is, when the transistor (T ₅₎ ON to OFF of the output transistor, the current flowing the transistor (T ₁₀₎ also turned ON via the resistor 502 to the base of the transistor (T _10), and as a result the resistance 506 ( Since the connection point of 503 falls to the ground potential, the transistor T ₁₁ is turned off. Therefore, the transistor T ₁₁ is turned on for the same time as the time δ ₁ (FIG. 6 (a)) when the current limit is applied to the output transistor.

When the transistor T ₁₁ is turned on, the electric charge that has been charged to the capacitor 508 at the polarity shown in FIG. 5 until then is discharged through the collector emitter of the transistor T ₁₁ . At this time, since the discharge time constant of the capacitor 508 is a constant value determined by the capacitance of the capacitor 508 and the value of the resistor 512, the discharge amount is a transistor (T ₁₁ ) as shown in the waveform at the lower right shown in FIG. ) Is almost proportional to the ON time, i.

If the current limit time δ ₁ is long, the discharge amount of the capacitor 508 increases, so that the residual charge decreases and the transistor T ₁₁ is turned off, and then the capacitor 508 becomes the resistor 507, the capacitor 508, and the diode ( The charging time Δ by the charging current flowing through the 509 and the condenser 513 becomes long. As a result, the charging voltage of the capacitor 513, as shown in FIG. 6 (c), increases, so that the conductivity of the transistor T ₁₂ is increased, and the resistance of the transistor T ₁ through the resistor 514 and the converter L ₅ is increased. As the current flowing through the base increases, the cutoff level of the base bias of the transistor T ₁ decreases from K ₁ to K ₂ , as shown in the sixth (d). As a result, the time that the transistor T ₁ is OFF decreases from P ₁ to P ₂ , resulting in a decrease in the time that the output transistor is ON. As shown in FIG. 6A, the current limiting time is δ ₁ to δ _2. Is shortened.

As shown in FIG. 2 (j), when the ignition timing is controlled by the delay angle ignition signal, the energization time to the output transistor becomes longer, and as a result, the time for which the current limit is applied becomes longer. The current time limit shortening circuit 5 acts so that the OFF time of the output transistor T ₁ becomes very short. Next, each component part of 7-11 which comprises the delay angle ignition signal generation circuit B is explained in full detail.

Trigger signal generator (7)

The trigger signal generation circuit 7 receives a reference ignition signal at the converter l ₁ connected to the collector of the transistor T ₃ . The reference ignition signal is input to the base of the transistor T ₁₃ via a resistor 701. The emitter of transistor T ₁₃ is connected to ground and the collector is connected to the base of transistor T ₁₄ , respectively, via a diode 702 connected in the forward direction. The emitter of transistor T ₁₄ is connected to ground and the collector is connected to the cathode of diode 703 respectively. The collectors of the transistors T ₁₃ and T ₁₄ are also connected to the collectors of the multi-collector transistor 801. The anode of diode 703 is connected to the anodes of two diodes 704 and 705, the cathode of diode 704 is connected to the collector of transistor T ₁₃ and the cathode of diode 705 is a pair It is connected to the stable multivibrator 8, respectively. A capacitor 706 using a 10 to 30 picofarad capacitance formed between the P layer and the N layer of the monolithic IC is connected between the base collector of the transistor T ₁₄ .

The operation of the trigger signal circuit 7 will be described with reference to FIG.

As shown in Fig. 7 (a), when the pick-up voltage changes and the base bias of the transistor T ₁ becomes the cut-off level, the transistor T ₁ is turned off, and at the same time, as shown in Fig. 7 (b), the transistor is turned off. (T ₃ ) also turns OFF. When the transistor T ₃ is turned OFF, a residual flows from the positive electrode of the power supply to the base emitter of the resistor 701 and the transistor T ₁₃ via the resistor 203 and the converter ℓ ₁ so that the transistor T ₁₃ is turned on. . This state is shown as a change in the potential of the collector 7 (c) also the transistor (T ₁₃₎ on. Then, since the base current of the transistor T ₁₄ which has flowed through the diode 702 up to that time does not flow suddenly, the transistor T ₁₄ is turned off. The charge of the illustrated Xi Zheng (極正) so far accumulated in the capacitor 706 of the transistor (T ₁₄₎ of claim 7 (d) the transistor (T _14), as shown in Figure to flow this reason through the base of the ON The transition from to OFF is delayed slightly.

Then picks up voltage changes from d point transistor (T ₃₎ that turns ON the transistor (T ₁₃₎ are so turned OFF, via the diode 702, the base current flows in the transistor (T _14), transistor (T ₁₄₎ is ON do.

Nevertheless, the ON time of the transistor T ₁₄ is delayed as shown in FIG. 7 (d) while the capacitor 706 is charged to the polarity shown. During this delay time t _a , no current flows to either of the diodes 703 and 704 as shown in Fig. 7 (e) and eventually through the diode 705 during this minute time t _a . A current flows through the bistable multivibrator 8, which becomes the trigger signal shown in Fig. 7E.

Bistable Multivibrator (8)

The bistable multivibrator 8 has transistors T ₁₅ and T ₁₆ whose operation is inverse to each other. The emitter of transistor T ₁₅ is connected to ground and the collector is connected via resistor 802 to one collector of multi-collector transistor 801 and the base via diode 803 connected in the reverse direction. It is connected to the collector of the transistor (T _16). The emitter of transistor T ₁₆ is connected to ground. The collector is connected to one collector of the multi-collector transistor 801, and the base is connected to the collector of the transistor T ₁₅ via a resistor 804, respectively. The cathode of the diode 705 is connected to the base of the transistor T ₁₅ .

The operation of the binocular multivibrator 8 will be described.

In through the diode 705. The trigger signal transistor is input to the base of (T _15), transistor (T ₁₅₎ is when the result transistor (T ₁₆₎ due to fall to the ground potential of the collector of the transistor (T ₁₆₎ ON The transistor T _{15 that} has been turned on until the base potential becomes the ground potential is turned off. A transistor (T ₁₆₎ is because if the collector potential is to rise OFF As a result, the ON state of the transistor (T _15), the current through the diode 803 to the base continues to flow transistor (T ₁₅₎ of is maintained.

The multi-collector transistor 801 is a transistor in which a plurality of collectors are formed for a pair of emitters and a base, and the base emitter currents in all the collectors are common, so that the currents flowing through the collectors are all the same. It is comprised as what is called a current miller circuit.

Triangle wave shaping circuit (9)

The triangle wave forming circuit 9 includes a transistor T ₁₇ having a base connected to the collector of the transistor T ₁₆ of the bistable multivibrator 8. The triangular wave forming circuit 9 is provided with a charge / discharge capacitor Q including two series-connected capacitors 901 and 902, and a constant current charging circuit for charging and discharging the capacitor Q as well. There is a constant current discharge circuit.

The transistor T ₁₈ is a transistor which forms the constant current discharge circuit, whose collector is connected to the capacitor Q, and the emitter is grounded. The base of the transistor T ₁₈ is connected to the ground via the emitter collector circuit of the transistor T ₁₇ and is connected to a constant voltage circuit for bringing the base potential to an electrostatic potential.

When there is no output from the bistable multivibrator 8, that is, when the collector voltage of transistor T ₁₅ is at a high level, transistor T ₁₇ is in the ON state, and the base of transistor T ₁₈ drops to the ground potential and the transistor ( T ₁₈ ) is OFF. At this time, the capacitor Q is charged by a separately formed constant current charging circuit. The transistors T ₁₉ and T ₂₀ are transistors forming a constant current charging circuit for charging the capacitor Q with a constant current, and the transistor T ₁₉ is a multi-collector transistor having two collectors to form a current mirror circuit. Doing. One of the collectors of the transistor T ₁₉ is connected to the capacitor Q, and the other is grounded via the collector emitter of the transistor T ₂₀ .

Since the emitter base of transistor T ₁₉ is common to the two collectors, the current flowing through the two collectors is the same value. On the other hand, since the base of the transistor T ₂₀ is connected to a constant voltage circuit for keeping the base potential constant, the current flowing through the collector emitter of the transistor T ₂₀ is a constant current. As a result, the current flowing into the capacitor Q connected to the collector of the transistor T ₁₉ is also charged, and the capacitor Q is charged with a constant current. The emitter of the transistor T ₁₉ is connected to the cathode of the Zener diode 605 whose anode is grounded while connected to the positive electrode of the power supply via an externally attached resistor 90. A zener diode 906 in which an anode is grounded in parallel with the zener diode 905 and a series circuit of the resistor 904 are connected. The movable piece of the switch SW is capable of switching the resistor 907 to the negative terminal h ₀ of the zener diode 906 with the anode. The terminal h ₀ receives a control signal that depends on the speed and load of the engine. When the movable piece is connected to the right end as shown, the zener diode 906 is connected in series with a resistor 907 and a diode 908 having a cathode grounded in parallel, and the resistor 907 and the diode 908 are connected in parallel. The connection point is connected to the base of the transistor T ₂₀ . The zener diode 906 is connected in parallel with three series connection circuits of the resistors 909, 910, and the cathode diode diode 911. The connection point between the resistor 910 and the diode 911 is a transistor. It is connected to the base of (T ₁₈ ).

The collector of transistor T ₂₂ is connected to the connection point of resistors 909 and 910 via a resistor 912, and the emitter of transistor T ₂₂ is connected to a diode 913 having a grounded cathode. . On the other hand, the collector of the transistor T ₂₁ with the emitter grounded is connected to the connection point of the capacitors 901 and 902. The bases of the transistors T ₂₁ and T ₂₂ are connected to the external signal terminals of the MIC.

The base circuit of transistor T ₁₈ is constant-voltageed by zener diode 906 and the base potential is maintained at a constant potential whose forward direction of diode 911 is determined by the voltage drop. The transistor T ₁₈ and its base circuit constitute a current mirror type constant current circuit, and the current flowing through the collector emitter current I ₁ of the transistor T ₁₈ and the resistors 909 and 910 of the base circuit ( I ₁ ) is configured to be uniform.

The base circuit of transistor T ₂₀ is constant voltage at zener diode 906 and its base potential is maintained at a constant potential whose forward direction of diode 908 is determined by the voltage drop.

A transistor (T ₂₀₎ and its base circuit is a current (I ₂₎ the collector-emitter flowing through the resistance 907 of the current (I ₂₎ to the base circuits of which constitute a constant current circuit of the current mirror transistor (T ₂₀₎ It is configured to be uniform.

As described above, the transistor T ₁₉ is a multi-collector transistor and the emitter base current is common to each collector, so that the current flowing through each collector becomes uniform. Therefore, the current I ₂ flowing through the collector emitter of the transistor T ₂₀ and the current flowing through the two collectors of the transistor T ₁₉ become uniform. The transistor T ₂₁ may connect the capacitors 901 and 902 in series, or may remove the capacitor 902 from the circuit. When a signal is input to the external signal terminal h ₁ , the transistor T ₂₁ is turned on to short the capacitor 902, so that the charging current I ₂ flows only in the capacitor 901. The capacity of the capacitor 901 is set to about 20 times the capacity of the capacitor 902. Therefore, when a signal is input to the external signal terminal h ₁ , the capacitor Q is practically imparted by the capacitor 901 having a large capacity, and when the signal is not present at the external signal terminal, the capacitor 902 having a small capacity is provided. Substantially gives the capacity of the capacitor Q. This terminal h ₁ is given a signal at the start of the engine, and is intended to eliminate the deterioration of the charging characteristics due to the low point of the power supply voltage at the start and the long ignition period.

On the other hand, the transistor T ₂₂ is turned on when a signal is input to the external signal terminal h ₂ to divide the current flowing through the resistor 909 by I ₃ . Therefore, since the current flowing through the resistor 910 is reduced to (I _1- I ₃ ), as a result, the base current of the transistor T ₁₈ is reduced so that the charging current of the capacitor Q is (I ₁ ), ( I _1- I ₃ ) decreases, and the time until the charge of the capacitor Q is discharged to reach a predetermined voltage becomes longer. This terminal h ₂ is also intended to solve the shortening of the discharge time due to the decrease in the charging voltage caused by the action of the terminal h ₁ by inputting a signal at the start-up.

The operation of the triangle wave forming circuit 9 will be described.

The trigger circuit transistor (T ₁₅₎ when the transistor (T _17), transistor (T ₁₇₎ to the base and the potential deterioration of the ON of 7 bistable multivibrator (8) by a signal at is OFF. Until then, the transistor (T ₁₈₎ had been the base is held at the ground potential by the transistor (T ₁₇₎ is a constant current discharging circuit of the capacitor (Q) formed by ON. In the transistor T ₁₈ , a current I _{1 of the} sum of the constant current I ₂ and the discharge current I _q , which has been charging the capacitor Q, flows.

This current I ₁ is given by the following equation when the transistor T ₂₂ is OFF.

However, V906: Zener diode 906 and brake over voltage.

V911: Forward voltage drop of diode 911.

R909 is the resistance 909 value.

R910: value of the resistor 910.

When the discharge proceeds and the terminal voltage of the capacitor Q reaches the reference voltage V _ref , the output circuit 10 of the rear stage is operated to invert the bistable multivibrator 8 so that the collector potential of the transistor T ₁₅ is high. Since the transistor T ₁₇ is turned on again to lower the base potential of the transistor T ₁₈ to the ground potential, the transistor T ₁₈ is turned off and the discharge of the capacitor is stopped. At the same time, the capacitor Q is charged by the constant current I ₂ supplied from the transistor T ₁₉ .

The constant current I ₂ is given by

However, V906: brake over voltage of the zener diode 906.

V908: Forward voltage drop of diode 908.

R907 is the resistance 907 value.

As described above, since the capacitor Q is discharged and charged by the constant currents I ₁ and I ₂ , the change in the terminal voltage of the capacitor Q is a constant slope m as shown in FIG. ), and form a triangular wave with (n). In this regard, the discharge current I ₁ is about 100 milliamps and the charge current I ₂ is about 5 milliamps.

When the transistor T ₂₂ is turned on, a portion I ₃ of the base current of the transistor T ₁₈ that determines the discharge current is classified to the diode 913 side. The fractionation ratio is set in the range of 1: 0.5 to 1: 3, but the area of the cathodes of the diodes 911 and 913 is also set in accordance with the fractionation ratio of the current so that the density of the current flowing through both diodes is approximately equal. This is effective for matching the forward temperature characteristics of the diodes 911 and 913 through which the large current flows compared to the charging current.

The half ground tip terminal of the capacitor Q is connected to the anode of the diode 903, and the cathode of the diode 903 is connected to the positive electrode side bus line of the power supply via the resistor 90. When the key switch K is closed, since the cathode axis of the diode 903 is at a high potential, no current flows through the diode 903. When the key switch K is opened, the power bus becomes the ground potential, and the charge of the capacitor Q is discharged to the ground through the diode 903 and the resistor 90. Then, when the key switch is closed, the terminal voltage of the capacitor Q is closed. Is 0.

Output circuit (10)

)입력단자에 접속되고 비교기의 정측(正

) 입력단자에는 콘덴서(Q)의 반접지측 단자가 접속된다. 비교기(CMP)의 출력단자는 쌍안정 멀티바이브레이터(8) 내의 트랜지스터(T₁₆)의 콜렉터에 접속됨과 동시에 트랜지스터(T₂₃)의 베이스에 저항(123)을거쳐 접속된다. 트랜지스터(T₂₃)의 에미터는 접지에 접속되어 있고 콜렉터는 전로(ℓ₂)를 거쳐 증폭회로(2)내의 트랜지스터(T₄)의 콜렉터에 각각 접속된다.The output circuit 10 has resistors 121 and 122 in series circuits and comparators CMP connected in parallel to the zener diodes 906 in the triangular wave forming circuit 9, and resistors 121 and 122 Makes its reference voltage (V _ref ). The other end of the resistor 122 having one end grounded on the other side of the comparator CMP

Is connected to the input terminal and the positive side of the comparator

The half ground terminal of the capacitor Q is connected to the input terminal. The output terminal of the comparator CMP is connected to the collector of the transistor T _{16 in the} bistable multivibrator 8 and connected via a resistor 123 to the base of the transistor T ₂₃ . The emitter of the transistor T ₂₃ is connected to ground, and the collector is connected to the collector of the transistor T ₄ in the amplifying circuit 2 via the converter L ₂ , respectively.

The operation of the output circuit 10 will be described.

When the capacitor Q of the triangular wave forming circuit 9 discharges and its terminal voltage reaches the negative reference voltage V _ref of the comparator CMP, the transistor (not shown) at the final terminal of the comparator CMP is turned on to output the terminal. 124 is brought down to ground, and as a result, the base of the transistor T ₁₅ of the comparator 9 is lowered through the potential conducting diode 803. When the transistor T ₁₅ is OFF, the collector potential rises. The base current of the transistor T ₁₆ flows through the resistor 804 and the transistor T ₁₆ is turned on to invert the bistable multivibrator, where the base current of the transistor T ₁₇ of the triangular wave forming circuit 9 flows. start because the transistor (T ₁₇₎ oN. transistor (T ₁₇₎ that is oN when stopping the discharge of the lowered to the ground potential the base of the transistor (T ₁₈₎ the transistor (T ₁₈₎ is OFF and the capacitor (Q). the results capacitor (Q) is re-charged with constant current (I ₂₎ It starts to charge to continue until the bistable multivibrator inverted by the triggering of the next pub screen signal is generated by the tree signal (7).

7 (f) shows the state of the inversion operation of the bistable multivibrator 8 as the change in the collector potential of the transistor T ₁₆ , so that the discharge time of the capacitor Q and the inversion time of the double safety multivibrator τ _3. ) Is a natural match.

On the other hand, the output of the comparator CMP turns off the transistor T ₂₃ by lowering the base potential of the transistor T ₂₃ to the ground potential.

As a result, a converter (l ₃₎ flows to the base of a current that flows through the transistor (T ₅₎ transistors (T ₅₎ is turned ON by the output transistor is off-cut of the ignition circuit 3, a primary current of the ignition coil block do. In this state, as shown in FIG. 2 (g), FIG. 2 (i), and FIG. 2 (j), the ignition coil is delayed by θ ₁ with respect to the reference ignition timing shown by the dotted line in FIG. 2 (j). It was found that the primary winding current of (C) was cut off. As shown in Fig. 7 (h), the output of the comparator CMP is output as a change in the potential which immediately falls to the ground potential when the discharge voltage of the capacitor reaches V _ref . This output corresponds to the point in time at which the collector potential of the transistor T ₂₃ switches from the ground potential to the high potential as shown in FIG. 7 (j), and as shown in FIG. 7 (j), the primary winding current ( Corresponds to the interruption point of Ic).

Switching circuit (11)

The switching circuit 11 includes a transistor T ₂₄ whose collector is connected to one collector of the multi-collector transistor 801, the emitter of which is connected to ground, and the base of which is an anode grounded diode 311. Is connected to the cathode of the power supply via a resistor 91 and a switch S attached to the outside. The collector of the transistor T ₂₄ is connected to the base of the transistor T ₂₅ via a resistor 312, and 27 characters are connected to the base of the transistor T ₂₆ via a resistor 313. The collector of transistor T ₂₅ is connected to the base of transistor T ₁₅ of bistable multivibrator 8 and the emitter is connected to ground, respectively.

On the other hand, the collector of the transistor T ₂₅ is connected to the base of the transistor T ₁₇ of the triangle wave forming circuit 9 and is connected to the emitter ground, respectively.

The operation of the switching circuit 11 will be described.

When the key switch K enters, current flows through the resistor 90 to generate voltage at each terminal of the zener diodes 905 and 906. As a result, the constant current charge / discharge circuit, the output circuit 10, the bistable multivibrator 8 and the trigger circuit 7 of the triangular wave forming circuit 9 connected in parallel to both diodes operate. Thus, the delay angle ignition signal generating circuit B outputs the delay angle ignition signal to the reference ignition control circuit A while the key switch K is closed.

The switch S is opened when the engine does not need a delay angle ignition signal. When the switch S is open, the transistor T ₂₄ is turned off and the collector potential rises, so that the emitter collector of the transistor 801 passes through the resistors 312 and 313 to the transistors T ₂₅ and T ₂₆ . Current flows in the base to turn on both transistors. When the transistor T ₂₅ is turned ON, the trigger signal flows to the ground via the diode 705 of the trigger circuit 7 connected to the collector, thereby making it impossible to invert the bistable multivibrator 8.

As described above, when the key switch K is opened, the charge of the capacitor Q is discharged through the diode 903. Therefore, the terminal voltage of the capacitor Q immediately after the key switch K is turned on is the reference of the comparator CMP. Lower than V _ref . Therefore, since the output terminal 124 of the comparator CMP falls to the ground potential and the base potential of the transistor T ₁₅ of the bistable multivibrator 8 is also low, the transistor T ₁₅ is turned off. Therefore, immediately after the key switch K is turned on, the transistor T ₁₅ of the bistable multivibrator 8 is turned off and the transistor T ₁₆ is turned on. As a result, the not the bistable multivibrator 8 as described above, inverted state transistor transistor (T _17), which is the base is connected to the collector of the (T ₁₅₎ is ON, and the transistor (T ₁₈₎ is turned OFF, the capacitor The discharge circuit of (Q) is to be cut off. However, when the switch S is open, the transistor T ₂₆ is turned on, and thus the base of the transistor T ₁₇ is lowered to the ground potential through the transistor T ₂₆ , so that the transistor T of the bistable multivibrator 8 is present. Even if ₁₆ ) is turned off, the transistor T ₁₇ does not turn on. As a result, the transistor T ₁₈ is turned on to form a discharge path of the capacitor Q, so that the charging current I ₂ of the capacitor Q also flows through the transistor T ₁₈ , so that the terminal voltage of the capacitor Q is zero. It remains in the state of the bolt. In the state where the terminal voltage of the capacitor Q is 0 volts, the output of the comparator CMP is at the ground potential as described above, so that the transistor T ₂₃ is OFF, and the output path l ₂ is always the transistor ( T ₄ ) is the collector potential and the coin top.

In this way, when the switch S is open, the delay angle ignition signal is not output from the output circuit even if the trigger signal is generated. The switch S is not limited to a mechanical switch but may be constituted by an electrical switch such as a transistor. In addition, the switch S may not be limited to a switch but may be constituted by a logical circuit switch composed of a combination of two or more switches.

In addition, depending on the type of engine, a condition for requesting a delay angle ignition signal may arise. In any case, other circuits can be used in common if only the circuit of the switch S is changed to one having an operating characteristic that meets the requirements of the engine.

Hereinafter, specific examples of the switch circuit will be described.

In FIG. 10, the part piled up by the dotted line shows the switch S. As shown in FIG. The switch circuit S has a series of series of resistors 51, zener diodes 52, 53 connected in parallel with the reference ignition control circuit A between the positive electrode and ground of the power supply. Both zener diodes are connected so that the ground side becomes the anode pole. The base of the transistor T ₂₇ is connected to the connection point of the two zener diodes, the collector of the transistor T ₂₇ is connected to the positive electrode of the power supply, and the emitter is connected to the ground via the resistor 91 and the diode 311. . The base of the transistor T ₂₇ is connected to the positive electrode of the power supply via the water temperature switch 54 and the resistor 55. The water temperature switch 54 is opened and closed according to the temperature of the cooling water of the engine. The water temperature switch 54 is turned off when the cooling water temperature is 50 ° C. or lower, and turns on when the water temperature switch is 50 ° C. or higher.

Zener diodes 52 and 53 are set to be brake off when the power supply voltage becomes 9 volts or more. Therefore, the switching circuit (S) are the water temperature and the transistor (T ₂₄₎ of the block (次段) By above 50 ℃ or jeonwo voltage is 9 volts or more when the transistor (T ₂₇₎ ON is ON, transistor (T _25), Since (T ₂₆ ) is turned OFF, the result is that the delay angle ignition signal output is generated in the converter (L ₂ ). In the switch circuit S, the ignition timing is delayed at the start of the engine (starter is driven and the power supply voltage is lowered to 9V or less) and after the warming-up operation is finished (the coolant temperature becomes 50 ° C or more). Can be controlled. Institutions require delayed ignition timing under the following conditions:

(1) During deceleration operation of the engine.

(2) When idling.

(3) Heavy load operation in low speed water area.

(4) At starter drive.

(5) When driving on notice.

(1) to (3) aim to reduce nitrogen oxides, (4) aim to improve engine starting characteristics, and (5) aim to correct excessive progression of the ignition timing. Therefore, various switch circuits can be designed by combining these conditions. The resistor 70 connected to the power supply model between the amplifier circuit 2 and the ignition circuit 3 is a resistor that limits the voltage across the amplifier circuit side. The zener diode 80 connected in parallel with the reference ignition signal generating circuit 1 is a zener diode for stabilizing the voltage applied to the reference ignition signal generating circuit 1 and the amplifying circuit 2.

8 (a) shows the output voltage waveform of the triangular wave forming circuit 9, that is, the terminal voltage waveform of the capacitor Q, the solid line shows the waveform during continuous rotation of the engine, and the dashed-dotted line shows the appropriate 1/2 at high speed. The waveforms at high speeds with a cycle are shown respectively.

As described above, the capacitor Q is charged at the constant current I ₂ represented by the formula (5) in the voltage V _ref when one ignition ends. This charging continues until the next reference ignition timing signal arrives.

8 (b) is a waveform showing the potential change of the output path ℓ ₂ of the delay ignition signal generating circuit B, (C) is a waveform showing the change of the primary winding current, and T is the period of the ignition timing. Α represents the delay angle ignition signal width. Therefore, the charging of the capacitor Q is performed for a time T-α, discharged between the time α to reach V _ref , and the voltage V _c1 at the point of charge / discharge switching at this time is given by the following equation.

C: capacitance value of the capacitor (Q).

When the reference ignition signal is generated, the trigger signal is output from the trigger circuit 7 and a constant current discharge circuit of the capacitor Q is formed, so that the capacitor Q discharges at the above-described constant current I ₁ . This discharge continues until the terminal voltage of the capacitor Q becomes V _ref , but this voltage V _ref is given by the following equation.

)는 기관의 회전수에 관계없이 충방전 전류비만에 의해 결정되는 것을 이해할 수 있을 것이다. 또 특히, 중요한 것은 지연각도(

)는 충전전류(I₂)에 직선 비례하는 것이다. 이 때문에 제1도에 있어서의 삼각파 형성회로(9)중의 스위치(SW)를 단자(h₀)측으로 절환하여 이 단자(h₀)에서 기관의 회전속도나 부하에 의존하는 제어신호를 가하면 점화시기의 지연각도를 그 제어신호에 직선 비례하여 변화시킬 수 있으므로 적정한 지연각 제어를 행할 수 있다.NT is an integer determined by the number of cylinders in the engine, so the delay angle (

It can be understood that) is determined by the charge and discharge current obesity regardless of the number of revolutions of the engine. Also important is the delay angle (

) Is linearly proportional to the charging current I ₂ . Therefore Applying the triangular wave-generating circuit (9) of the switch (SW) to the terminal (h _0), the control signal depending on the rotation speed or load of the engine in the terminal (h ₀₎ and switches to the side of the first is also the ignition timing Since the delay angle can be changed in linear proportion to the control signal, appropriate delay angle control can be performed.

In Fig. 9, A is a lead angle characteristic obtained by the negative pressure lead angle mechanism of the centrifugal lead angle mechanism, and B is a characteristic obtained by the present invention, which is a delay angle ignition characteristic which is always delayed by a constant angle by its lead angle characteristic.

The charging current I ₂ may be changed into a step type as the circuit shown in FIG. In FIG. 11, parts of the switch SW and the resistor 907 of the triangle wave forming circuit 9 of FIG. 1 are replaced with other circuit components. The connection point of the zener diode 906, the resistor (907a) to byeongyeol, (907b), (907c) and a diode 908 direct thermal circuit is connected in which a resistance (907a) and (907b), the emitter of the transistor (T ₃₀₎ Is connected, and the transistor T ₃₁ is connected to the connection point of the resistors 907b and 907c. The collectors of the transistors T ₃₀ and T ₃₁ are respectively connected to the cathode side of the zener diode 906, and their bases are connected to the control signal generator 903.

The control signal generator 930 applies a signal for conducting or cutting off the transistor T ₃₀ or T ₃₁ to the base of the transistors T ₃₀ and T ₃₁ depending on the rotational speed or load of the engine. By shorting one resistor 907c or two resistors 907b and 907c of the series resistors 907a, 907b, and 907c or by forming a series resistor of three resistors (5) The charging current I ₂ shown in the equation can be changed into a step type.

As described above, according to the present invention, the front end of the delay angle ignition signal {figure 2 (g)} arrives before the rear end of the reference ignition signal {figure 2 (f)} arrives. (j) c} was cut off in the middle, and there was no possibility of causing a stigma.

Claims (1)

A circuit that generates a reference ignition pulse in synchronization with the engine and a leading edge synchronized with the rear end of the reference ignition pulse, and the perception that generates the rear end at the point of time that is perceived by the required rotation axis angle of the engine after the reference ignition pulse. Internal combustion engine ignition with an ignition circuit operable to cause a current to flow in the primary winding of the ignition coil based on the circuit for generating the ignition pulse and the tip of the reference ignition pulse to cut off the primary winding current at the rear end of the perceptual ignition pulse. In the timing control circuit, the above-mentioned perception ignition pulse generating circuit has a capacitor for charge and discharge, a first constant current circuit for always supplying a first current to the capacitor, and a reverse polarity with the first current to the capacitor. A second constant current circuit for supplying a second current having a value greater than the second current, and the second current flowing in synchronization with a reference ignition pulse to cause a terminal voltage of the capacitor; It has a switching circuit which operates to cut off when this reference level is reached, and an output circuit which generates a perceptual ignition pulse having a pulse width corresponding to the period in which the second current flows. The internal combustion engine ignition timing control circuit has an engine ignition. A delay circuit for delaying the rear end of the pulse later than the front end of the late ignition pulse and the period from the front end of the reference ignition pulse to the rear end of the late ignition pulse by superimposing the late ignition pulse on the reference point and the pulse. An ignition timing control circuit of an internal combustion engine having a circuit for inputting an ignition pulse having a pulse width into an ignition circuit.

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