JPS61187576A - Engine ignition control device - Google Patents

Abstract

PURPOSE:To suppress the secondary voltage of an ignition coil from being generated by discharging charges charged in a charging/discharging circuit at the predetermined time constant when an abnormality of an engine is detected so that the base current of darlington power transistors can be gradually decreased. CONSTITUTION:Darlington power transistors Tr29A, Tr29B are operated by a signal from an ignition control unit via a switching circuit 27, thereby the current through ignition coils 14A, 14B is controlled to generate sparks on ignition plugs 15A, 15B. The base voltage is applied to bases of the said Tr29A, Tr29B via a voltage feed switch circuit 30. When an abnormality is detected by a fail safe detection circuit (not shown in the figure), a signal ST is made invalid, a transistor Tr4 is turned on, a transistor Tr2 is turned off, the voltage feed from the said circuit 30 is shut off, on the other hand, capacitors C3, C4 are discharged, and the base current of the Tr29A, Tr29B is decreased gradually.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine ignition control device, and in particular, when an engine abnormality is detected and the engine is stopped, the secondary voltage generated in the ignition coil is controlled to ignite the engine. The present invention relates to an engine ignition control device that has a function of preventing the generation of sparks.

[Prior art]

Conventionally, as a technology in this field, Japanese Patent Application Laid-Open No. 55-4
There was one described in Publication No. 6030. FIG. 2 is a circuit diagram showing the configuration of the ignition system of a conventional ignition control device.
FIG. 3 is a diagram showing voltage/current waveforms of various parts showing the operation. If the engine ignition control is normal, the ST double signal input to terminal 1 becomes ``H'' as shown in Figure 3 (a), and the operation of the ignition system is controlled by the ST double signal input to terminals 2 and 3 as shown in Figure 3 (a).
The base currents of the Darlington power transistors 4 and 5 change to the third level by the 0UTA and 0UTB signals as shown in b).
As shown in FIG. 3(c), the current flowing through the ignition coil 6.7 is interrupted as shown in FIG. 3(d).

As a result, high voltages Pu and Pv as shown in FIG. 3 (,) are generated on the secondary side of the ignition coil 6.7, causing sparks to fly to the ignition plugs 8 and 9, and normal operation is repeated. By the way, when the engine ignition control device detects an abnormality in the engine, the S
The T-fold signal falls as shown within the dotted line frame in FIG. 3(a), and the base currents of the Darlington power transistors 4 and 5 are cut off as shown within the dotted line frame in FIG. 3(C).

If the ignition coil 6.7 is in the energized state, then Fig. 3 (d
), the current flowing through the ignition coil 6.7 is cut off to prevent unnecessary current from continuing to flow through the ignition coil 6.7.

[Problem that the invention seeks to solve]

However, in the conventional device with the above configuration, before the engine ignition control device detects an engine abnormality, the Darlington power transistors 4 and 5 are in II Q N 71 and the ignition coil 6.7 is in the energized state, and the engine ignition control device When an abnormality is detected, the abnormality detection signal generates a high voltage Px at a position other than the normal ignition position as shown in the dotted line frame in Fig. 3(e), and this high voltage causes the ignition plug 8 to
, 9 generates an ignition spark. This ignition spark has the disadvantage of causing serious problems such as blowback to the carburetor, knocking, etc., and safety and engine deterioration.

The present invention has been made in view of the above points, and has a function of preventing the generation of ignition sparks if the ignition coil is energized when the engine ignition control device detects an engine abnormality and stops the engine. An object of the present invention is to provide an engine ignition control device.

[Means for solving problems]

In order to solve the above problems, the present invention provides an engine ignition control device with a voltage supply switch circuit that supplies base current to the Darlington power transistor, and a voltage supply switch circuit that uses an abnormality detection signal detected by the ignition control unit when an engine abnormality occurs. and a charging/discharging circuit that discharges the charge through the base and emitter of the Darlington power transistor when the voltage supply switch circuit is cut off.

[Effect]

By configuring the engine ignition control device as described above, the Darlington power transistor
Even if the ignition control unit detects an abnormality in the engine and shuts off the voltage supply switch circuit, the base current of the Darlington power transistor suddenly drops to zero due to discharge of the charging/discharging circuit. Since the primary voltage of the ignition coil is not suddenly cut but is gradually reduced to zero, the generation of the secondary voltage of the ignition coil is suppressed and sparking of the ignition plug can be prevented.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a block diagram showing the configuration of an ignition control system for controlling the ignition of a 4-cylinder engine with a narrow angle of 90 mm according to the present invention. Ignition control system.

Protrusions 11a are provided at 45 degree intervals on the circumference of a rotating body 11 that rotates coaxially with the crankshaft of the engine, and rotation angle information (hereinafter referred to as crank angle) with one of the protrusions 11a missing is detected. Electromagnetic pickups 12A, 12B; an engine control unit 13° that uses signals from the electromagnetic pickups 12A, 12B as input signals to control optimal energization/ignition timing of the engine; connected in series to the output side of the control unit 13; Ignition coils 14A, 1 that can send sparks to spark plugs 15A, 15B according to output energization/cutoff signals
Consists of 4B.

The engine control unit 13 includes waveform shaping circuits 2IA, 2
1B, D-type flip-flops 22A, 22B, fail-safe detection circuit 23. Microcomputer 24, count circuits 25A, 25B.

Signal selection circuits 26A, 26B, switching circuit 27,
D-type flip-flop 28, power transistor 29A
, 29B, and an inverter NIL.

FIG. 5 is a circuit diagram showing the configuration of the waveform shaping circuits 21A, 21B of the engine control unit 13, and the waveform shaping circuits 2LA, 21B include resistors R1, R2, R3, Zener diodes ZD1. Electromagnetic pickups 12A, 12 are composed of transistors Tri, etc., and are input to input terminals.
The detection signals SGA and SGB from B are shaped, and the shaped signals SA and SB are output from the output terminals.

FIG. 6 is a block diagram showing the configuration of counter circuits 25A and 25B of the engine control unit 13, and each of the counter circuits 25A and 25B has flip-flops FFI, FF2. It is composed of AND gates ANDI and AND2 and preset counters PCI and PC2.

FIG. 7 is a block diagram showing the configuration of the signal selection circuits 26A and 26B of the engine control unit 13, and each of the signal selection circuits 26A and 26B includes a multiplexer M.
PXI, MPX2. It is composed of an inverter NI2 and a flip-flop FF3.

FIG. 8 is a block diagram showing the configuration of the fail-safe detection circuit 23 of the engine control unit 13. AND gate AND5. AN
D6, OR gate ○R1, OR2, counter Cm, resistor R], 4, capacitor C5, inverter IN4, etc.

FIG. 1 is a diagram showing the configuration of the switching circuit 27 of the engine control unit 13 and the connection relationship of the Darlington power transistors 29A, 29B, etc. The switching circuit 27 includes transistors Trl to Tr6, resistors R4 to R13, diodes DI and D2, Zener diode ZD2, capacitors C3 and C4, and an AND gate.

In addition, in FIG. 4, 31 is a battery power supply, 32 is a regulator, and the diode 3 is connected from the battery power supply 31.
Voltage Vcc is supplied to the switching circuit 27 through 3, the output voltage VDD of the regulator is supplied to the D-type flip-flops 22A, 22B, 28, etc., and the voltage VBA of the battery power supply 31 is supplied to the ignition coils 14A, 14B.
Supplied to the next side.

Due to the rotation of the rotating body 11, the electromagnetic pickups 12A, 12
The detection signals SGA and SGB detected at B are input to the waveform shaping circuits 21A and 21B of the engine control unit 13 and are waveform-shaped to become signals SA and SB. The signal SA is connected to the D-type flip-flop 22A and the fail-safe detection circuit 23.
The signal SB is guided to a D-type flip-flop 22B.

Each D-type flip-flop 22A, 22B receives a signal SA
, SB transitions at the terminals Q and Q, respectively, and inputs the interrupt signal INT and the reference position detection signal 5TATUS to the microcomputer 24, respectively. Microcomputer, 24 is interrupt signal INT 11L
Upon receiving the It level, the reference position detection signal 5TATUS becomes H.
'' or II L71, and sends out a signal F/FCLR to reset the above-mentioned flip-flops 22A and 22B, thereby resetting the D-type flip-flop 22A.

22B, adjust the crank angle 5TAGE, and perform logical operations necessary for engine control such as energization/ignition control.

The counter circuits 25A and 25B latch the energization timing data and ignition timing data from the microcomputer 24 from the data bus DTB, and
At the crank angle 5TAGE determined by the microcomputer 24, the signals Son and 5off are sent to the count circuits 25A and 25B, so that the preset counters PC1 and PC2 start counting down, and the count value reaches 0''. At the point in time, a single energization command signal Con and an ignition command signal Coff are output to the signal selection circuits 26A and 26B (see FIG. 5).

The signal selection circuits 26A and 26B switch the signal SEL determined by the microcomputer 24 according to the engine state, such as the cranking state during engine startup and low rotational speed range, and the normal rotational range other than the erroneous cranking state. to select the output signals Can and Coff of the counter circuits 25A and 25B, or to select the output signals Hon and Hof by crank angle 5TAGE discrimination.
f is selected and the signal OUT is output (see Figure 7)
.

The D-type flip-flop 28 is connected to the microcomputer 2
4 detects the reference position first and crank angle 5TAGE"
After completing the processing of "01", the port output signal 5TART of the microcomputer 24 changes from the II H1 level to "L".
The signal ST becomes valid at the moment when the signal ST transitions to the ``level.'' This signal ST becomes invalid both when the power supply voltage is turned on and when the fail-safe detection circuit 23 detects an abnormality.
At this time, the microcomputer 24 is also reset.

The fail-safe detection circuit 23 receives the output signal SA from the waveform shaping circuit 2LA and the output signal ○U from the signal selection circuit 26A.
TA and the signal ST from the flip-flop 8 are input, and the fail-safe detection circuit 23 counts up the counter Cn with the signal SA after the signal ST becomes valid, and resets the counter Cn with the signal 0UTA. The switching circuit 27 monitors input/output sequence breakdown (see Figure 8) when the signal ST is not valid (see Figure 8).
II L +jn level is the transistor Tr2. Tr
3 becomes OFF, and the signal 0UTA and signal 0UTB are turned off.
Regardless of the transition from the "H" level to the "L11 level" or from the "L" level to the reHIt level, the power transistors 29A and 29B are cut off, and the signal S
When T becomes valid (''Hn level), signal 0UT
A, signal 0UTB is II Hu L, bell to II L
To I+ level or from raL” level #HI+
By transitioning to the power transistor 29 level, the power transistor 29
A.

29B is energized or cut off (see Figure 1) 1
Turn on the power to the ignition coils 14A and 14B.

The operation of the sixth-order ignition control system that performs OFF control and generates a high voltage on the secondary side will be described in detail with reference to the timing chart shown in FIG. 9 and the flowchart shown in FIG.

First, when the power is turned on, a battery voltage is applied to the engine control unit 13, and the output of the inverter IN4 is changed to l# by a time constant consisting of the resistance and capacitance of the resistor R14 and capacitor C5 of the fail-safe detection circuit 23 shown in FIG. The microcomputer 24, which had been reset by the output signal RESET of the OR gate OR2 until it moved from the HH level to the ``LL'' level, is reset as shown in FIG. 10(A).
Start from the flow shown below. Initial settings required for the engine control unit 13 (e.g. engine included angle settings,
Input/output port of microcomputer 24.

Initial setting processing of internal registers, etc.) (Step 1.
00), after performing the initial settings, in order to reset the D-type flip-flops 22A and 22B, the microcomputer 24 sends out a reset pulse F/PC;LR.
Flip-flop 22A.

22B is reset (step 101). Is the interrupt signal INT from the flip-flop 22A at H” level?II
If the interrupt signal INT is II Hl#, a self-jump is performed, and if the interrupt signal is "L"), the process proceeds to the next step 103.

In the step 103, it is determined whether the reference position detection signal 5TATUS from the flip-flop 22B is at the IIH'' level or the II L 1g level, and if the reference position detection signal 5TATUS is l#HH, the step 101 is performed.
Returning to , the reset signal F/FCLR for resetting the flip-flops 22A and 22B is sent again, and the above flow is repeated. The reference position detection signal 5TATUS is re
If L u, proceed to step 104. The step 10
In step 4, the crank angle 5TAGE of the internal register of the microcomputer 24 is set to II OI H, the reset signal F/FCLR is sent (step 105), and cranking processing is performed at the crank angle 5TAGE="01" (step 106). , the signal 5TART that enables the function of the engine control unit 103 is set to II HI.
Output is made by transitioning from the t level to the "'L" level (step 107). Next, the flip-flop 2 is output again.
Interrupt signal INT from 2A is ``H'' level JI
Step 108) to determine if it is L Pn level, self-jumps when interrupt signal INT="H" and outputs 1 interrupt signal IN
When T=“L”, the process proceeds to step 109. In step 109, a reset signal F/FCLR is sent,
Perform cranking processing corresponding to each crank angle 5TAGE number (step 110), and
The number is incremented (step 211). Next, it is determined whether the crank angle 5TAGE is II 871 or not (step 112). If it is not "8", return to the step 108, repeat the flow from step 108 again, and if the crank angle 5TAGE is re 8 +t, proceed to step 112). Proceed to 113. In step 113, an interrupt to the microcomputer 24 is permitted. At this point, the processing flow shown in FIG. 10(B) becomes the first priority program, and the processing flow shown in FIG. 10(A) becomes the second priority program. Step 114, which became the second priority program, and the processing at step 114 are executed at a time when the first priority program is not being processed, and the ignition timing calculation process (step 114) is performed based on the information obtained from the processing of the first priority program. and energization timing calculation process (step 115)
Operate repeatedly.

Next, in the program that has been given the first priority in FIG. ). Next, it is determined whether the reference position detection signal 5TATUS is at the HIf level or the II L1g level.Step 151) If it is #H'y, the process proceeds to Step 153, and if it is di LH, the crank angle is forcibly set to 5TAGE3"01". Set (Step 15)
2). In step 153, the reset signal F/FCL
Send R and proceed to step 154. The step 154
Then, at a predetermined low engine speed, is the cranking processing rotation performed an energization operation (signal Hon in Fig. 9) and an ignition operation (signal Hoff in Fig. 9) at an interrupt of a predetermined crank angle of 5TAGE? Or, it is determined whether it is a normal processing rotation speed for operating the energization timing and ignition timing calculated from the rotation speed information, and if it is determined to be cranking processing, the signal SEL is set to II H# level (step 159) Next. At crank angle 5, one pulse of the signal Hoff is sent at crank angle 5TAGE determination.
If TAGE, send a Hoff signal.Step 16
0).

If not, the process goes to step 161, and here again, one pulse of the signal Hon for determining the crank angle 5TAGE is sent out.If the crank angle is 5TAGE, the Hon signal is sent out, and the process goes to step 162.

In step 154, if normal processing is determined,
Proceeding to step 155, the signal SEL is set to "[, 7 levels." At the primary crank angle 5TAGE determination, the signal
If the crank angle is 5TAGE, which selects one off pulse, send out the signal 5off (step 156); otherwise, go to step 157 and select the crank angle 5TAG.
If the crank angle is 5TAGE, which sends out one pulse of the signal Son in the GE judgment, the signal Son is sent out, otherwise the process goes to step 158, and the crank angle 5TAGE judgment is made to determine whether or not to load the calculated value to each counter. Then, the crank angle 5TAGE is incremented (step 162), the registers saved in step 150 are restored (step 163), and from the execution of the first priority program in FIG. 10(B) to the second priority program in FIG. Start executing the priority program.

The cranking process in FIG. 9 is a timing chart during low rotation (such as when starting the engine), and the cranking process is performed using the detection signal S from the electromagnetic pickups 12A and 12B shown in FIG.
GA and SGB are connected to waveform shaping circuits 2LA and 2 shown in FIG.
1B, it is shaped into a signal SA and a signal SB. The signals SA and SB fall respectively, and the terminal Q of the D-type flip-flop 22A is latched to the II L7 level, the terminal Q of the D-type flip-flop 22B is latched to the #HII level, and the terminals INT and 5TATU of the microcomputer 24 are latched.
The reference position is determined based on the 1 interrupt signal INT input to S and the reference position signal 5TATUS being "H" level, and the signal 5TART of the microcomputer 24 being set to "H" level.
'' level to II L 1g level, the control of the engine control unit 13 is enabled, and crank gear processing is performed for at least one rotation.
The interrupt signal INT is timed every "L' level by an internal timer, and it is determined whether cranking processing or normal processing is performed by determining the rotational speed and angle/time conversion.

Figure 12 shows each crank angle 5TAGE at an included angle of 90 degrees.
As shown in the figure, at each crank angle 5TAGE, the signal Hon.

Sends the signal Hoff and performs engine ignition control.

In addition, the normal processing in Fig. 9 is a timing chart during normal operation, and the reference position detection is equivalent to cranking processing, but ignition timing calculation and energization timing calculation are performed, and as shown in Fig. 12. The calculation data at each crank angle 5TAGE is calculated by counting circuits 25A and 25 shown in FIG.
B's preset counters Pct and PC2 are loaded, and the start signals Son and Sof f are sent out at the next interrupt to control the engine.

Here, the ignition timing calculation assumes that the advance range is -45 degrees, the time just before the calculation required for one crank rotation is T (μS), the advance angle calculated from the rotational speed is θ (degrees), and the time per 1 degree angle is T (μS). t
=T/360. By fixing the clock cycle φ (μS) used for the preset counter and the ignition start signal 5off as shown in FIG. 11, the calculation formula is To f f = (45-θ) x T/360x
1/φ. In addition, the energization time calculation is To n = (Tx - To f f) /T 145 as the energization time Tx (μS) obtained from the previous rotation information, and Son of energization start crank angle 5TAGE is 5on = ignition start crank The angle 5TAGE-(quotient tl of Ton) becomes, and furthermore, the energization time from starting 5TAGE is To
nCLK= (1-To n remainder) X (T/45
)XI/φ, and each process is performed at the crank angle 5TAGE shown in
Processing is performed based on the determination, and engine control is performed.

Next, the output signals 0UTA of the signal selection circuits 26A and 26B,
Switching circuit 2, which constitutes the main point of the present invention, operates in response to signal ST from 0UTB and flip-flop 28.
7 will be explained in detail based on FIGS. 1 and 11. The moment when the signal ST becomes valid (see Figure 11(a))
At , the transistor Tr4 is turned off, and the base voltage of the transistor Tr2 is divided by the resistor R4 and the Zener diode ZDZ, and this voltage is applied to the base of the transistor Tr2 through the resistor R5. By applying this voltage, the transistor Tr2 becomes an operating region, and the transistor Tr3 also becomes an operating region, so that the voltage supply switch circuit 30 is configured. Also, signal ST, signal 0UTB, ○UTA, and AND gate 3.
The output from AND4 is applied to the bases of transistors T r 5 r T r 6 through resistors RIO and R13 to perform a 0N10FF switching operation. Now, signal ST is valid 11H, +? Level and signal 0UTA
, 0UTB is l/L 7 levels, then transistor Tr5. Tr6 is in the "OFF" state, and the voltage value supplied from the voltage supply switch circuit 30 charges the capacitors C3 and C4 through the diodes DI and D2 and the resistors R8 and R11, and this charging voltage is applied to the resistors R9 and R1.
2 through Darlington power transistor 29A, 2
Applied to the base of 9B. This results in Darlington power transistor 29A.

29B enters the II ON II state. In other words, the signals 0UTA and ○UTB change from LL L 17 level to '''H.
By transitioning to the II level, the Darlington power transistors 29A and 29B become "OFF", and the signals 0UTA and 0UTB change from the ItHjt level to the II level.
Due to the transition to the Ln level, the Darlington power transistors 29A and 29B enter the P○N+ state. In this way, the base voltages of the Darlington power transistors 29A and 29B change due to the signals ○UTA and 0UTB (see FIG. 11(c)), and the Darlington power transistors 29A and 29B become II ON Hl, #
OFF"L, primary voltage of ignition coils 14A, 14B (
FIG. 11(d)) Control. Here, the reason why the base current waves of the Darlington power transistors 29A and 29B rise gradually is that the transistors Tr5. This is based on the time constant formed by the resistance and capacitance when Tr6 turns OFF 11 and the voltage supply switch circuit 30 charges the capacitors C3 and C4 through the resistors R8 and R11.

Also, Darlington power transistor 29A.

29B is in the “ON” state, the failsafe detection circuit 23
When detecting an abnormality, the D-type flip-flop 28 is reset and the signal ST becomes invalid. When the signal ST becomes invalid, the transistor Tr4 becomes ○N +t, and the transistor Tr2 turns "OFF", thereby cutting off the voltage supply from the voltage supply switch circuit 30. In addition, transistor Tr5. At the same time, Tr6 becomes '○FF'.

The circuit configuration in this state is to connect capacitors C3 and C4 whose one end is grounded, the other end of the capacitor C3 and C4 to resistor values R9 and R12, and the other end of resistor R9 and R12 to the Darlington power transistor. It is connected to the bases of Darlington power transistors 29A and 29B, and the emitters of Darlington power transistors 29A and 29B are grounded. Darlington power transistors 29A and 29B are ○N 7
If an abnormality is detected in state 1, the electric charges charged in capacitors C3 and C4 are transferred to resistors R9 and R12 and Darlington power transistor 29A.

Gently discharges through the base emitter of 29B (
(See inside the dotted line frame in FIG. 11(c)). This prevents the primary voltage of the ignition coils 14A and 14B from being cut off suddenly (
(see dotted line in Figure 11(d)), the rise is gradual;
Secondary voltage generation in the ignition coils 14A and 14B is suppressed,
Generation of ignition sparks in the ignition lines 15A and 15B is prevented (
(See inside the dotted line frame in FIG. 11(e)).

As described above, according to the above embodiment, the voltage supply switch circuit 30 is cut off in response to the signal ST that detects an abnormality in the engine, and the signals 0UTA and ○UTB are connected to the AND4.
By forcibly turning OFF with AND3, when an abnormality in the engine is detected, a closed circuit between the charge resistors R9 and R12 stored in capacitors C3 and C4 and the base-emitter of Darlington power transistors 29A and 29B is turned off for a predetermined time. Since it discharges at a constant rate and gradually reduces the base current of the Darlington power transistor, it suppresses the generation of secondary voltage in the ignition coils 14A and 14B.
It is possible to prevent the generation of ignition sparks of 5A and 15B, and it is expected to improve safety and prevent engine deterioration.

Furthermore, when the current is applied during the intake stroke, the internal pressure in the cylinder of one engine is low, and the ignition coil 14, which starts the ignition spark,
The secondary voltage of A and 14B becomes low, and the 2 that occurs when energized
The secondary voltage of the ignition coils 14A, 14B is also increased as the current supplied to the bases of the Ridderlington power transistors 29A, 29B gradually increases due to the charging time constant of resistors R8, R11 and capacitors C3, C4. It can be expected to suppress the generation of voltage and prevent the generation of ignition sparks.

〔Effect of the invention〕

As explained above, according to the present invention, the electric charge charged in the charging/discharging circuit when an engine abnormality is detected is discharged at a predetermined time constant, and the base current of the Darlington power transistor is gradually decreased. The generation of secondary voltage can be controlled and the generation of ignition sparks can be prevented, improving safety and the life of the engine. In addition, even when the current is in the suction process, the base current supplied to the base of the Darlington power transistor by the charging/discharging circuit gradually increases the secondary voltage generated in the ignition coil. Excellent effects such as being able to suppress the generation of 5-ignition sparks can be obtained.

[Brief explanation of drawings]

The first drawing is a circuit diagram showing the configuration of an ignition system such as a switching circuit used in the engine ignition control device according to the present invention, FIG. 2 is a circuit diagram showing a conventional switching circuit, and FIG. 3 is a timing diagram for explaining its operation. 4 is a block diagram showing the overall configuration of the engine ignition control device according to the present invention; FIG. 5 is a circuit diagram showing the configuration of the waveform shaping circuit; FIG. 6 is a block diagram showing the configuration of the counter circuit; 7 is a block diagram showing the configuration of the selection circuit, FIG. 8 is a block diagram showing the configuration of the fail-safe detection circuit, FIG. 9 is a timing chart diagram for explaining the operation of the ignition control device in FIG. 4, Fig. 10 is a diagram showing the processing flow of the microcomputer, Fig. 11 is a timing chart diagram for explaining the operation of the switching circuit of Fig. 1, and Fig. 12 is a diagram showing the outline processing contents of the crank angle 5TAGE. . In the figure, 11... Rotating body, L2A, 12B... Electromagnetic pickup, 13... Engine control unit, 14A
. 14B...Ignition coil, 15A, 15B...Ignition plug, 30...Voltage supply switch circuit.

Claims (1)

[Claims] In an engine ignition control device that operates a Darlington power transistor via a switching circuit in response to a signal from an ignition control unit, and controls current flowing through an ignition coil to generate a spark in an ignition plug, base power is supplied to the Darlington power transistor. a voltage supply switch circuit for shutting off the voltage supply switch circuit according to an abnormality detection signal detected by the ignition control unit when the engine is abnormal; An engine ignition control device characterized in that a charging/discharging circuit is provided for discharging through the base and emitter of a Darlington power transistor.