JPH05263743A - Ignition device for internal combustion engine - Google Patents

Abstract

PURPOSE:To improve packaging density by forming a circuit for outputting an ignition signal to a power transistor, of an integrated circuit having inverters equal in number to cylinders, and supplying output currents at the ignition signal output time through resistances connected to the outside of the integrated circuit. CONSTITUTION:An internal combustion engine ignition device 1 is formed of a CPU 10, an electronic distributing circuit 11, an ignition output circuit 12 formed of an integrated circuit, plural resistances 13, 14 for controlling the output current of an ignition signal, and a constant voltage circuit 15 for generating a power signal 15a of constant voltage. Current application to ignition coils 3-8 provided at plural cylinders is controlled by a power transistor 16. A reference position signal 9a and an angle signal 9b detected by a rotation detector 9 are outputted to the internal combustion engine ignition device 1, and the currents flowing from the respective cylinder ignition signals 12a-12f outputted from the ignition output circuit 12 are supplied from the constant voltage signal 15a of the constant voltage supply 15 through the respective resistances 13, 14 connected to the outside of the integrated circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine ignition device, and more particularly to an electronic distribution ignition signal output circuit for outputting an ignition signal for each cylinder.

[0002]

2. Description of the Related Art A conventional electronic distribution ignition signal output circuit is composed of transistors 60 to 65 and current limiting resistors 50 to 55 as shown in FIG.
Depending on the state of 1a to 11f, the transistors 60 to 65 are turned on
N / OFF is performed and the cylinder ignition signals 12a to 12f are output. At this time, the current output to each of the cylinder ignition signals 12a to 12f is supplied from the current limiting resistors 50 to 55 connected to the collectors of the respective transistors 60 to 65. The other side of the current limiting resistors 50 to 55 is connected to the battery 2, and the voltage of the level of the battery voltage signal 2a is output to the cylinder ignition signals 12a to 12f. It is a configuration of an ignition signal output circuit.

[0003]

In the above-mentioned prior art, since the ignition signal is output from the battery 2 via the current limiting resistors 50 to 55, the power consumption of the current limiting resistors 50 to 55 is large and the heat generation is large. There was a problem of becoming. Further, in order to deal with this heat generation amount, it is necessary to use a resistor having a large withstand power consumption. Therefore, there is a drawback that the outer shape of the resistor becomes large and the mounting area becomes large when mounted on a printed circuit board.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an internal combustion engine ignition device which suppresses the heat generation of the above resistance, reduces the mounting area when mounted on a printed circuit board, and improves the mounting density.

[0005]

In order to solve the above problems, the current supply of the ignition signal is supplied from the constant voltage power supply instead of the battery, and
This is accomplished by making the electronic distribution ignition signal output circuit an integrated circuit (IC).

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the circuit configuration of the present invention. Reference numeral 1 is an internal combustion engine ignition device. The internal combustion engine ignition device 1 includes a CPU 10, an electronic distribution circuit 11, and an ignition output circuit 1.
2. Resistors 13 and 14 that control the output current of the ignition signal, and a constant voltage circuit 15 that generates a power supply signal 15a having a constant voltage (for example, 5 V constant). Reference numeral 2 denotes a battery, which is a power source of the internal combustion engine ignition device 1.
Ignition coils 3 to 8 are provided in each cylinder, and energization is controlled by the power transistor 16. A rotation detector 9 outputs a reference position signal 9a and an angle signal 9b to the internal combustion engine ignition device 1.

FIG. 2 is a timing chart for explaining the operation of the circuit shown in FIG. The reference position signal 9a output from the rotation detector 9 indicates that the piston of the internal combustion engine is, for example, 1 after top dead center.
A pulse is generated when a predetermined position such as 0 degree is reached. Further, the angle signal 9b generates a pulse at every predetermined angle of the internal combustion engine (for example, the signal level is inverted every 1 degree). The above signal is input to the internal combustion engine ignition device 1, and is input to the CPU 10 and the electronic distribution circuit 11. The CPU 10 calculates the optimum ignition timing based on the input signal and outputs the ignition signal 10a. Although not shown, the ignition signal 10a output circuit configuration inside the CPU 10 is the same as the configuration described in Japanese Patent Application No. 63-276259, and comprises an ignition timing counter and an energization start timing counter. The internal configuration of the electronic power distribution circuit 11 is also Japanese Patent Application No.
No. 276259, it is composed of a cylinder discrimination circuit and a distribution circuit, and the reference position signal 9a
The number of angle signals 9b during the High period is counted to determine the cylinder in the ignition order, and the ignition signal 10a output from the CPU 10 is distributed to each cylinder based on this determination signal. That is, the ignition signal 10a output from the CPU 10 is output in synchronization with the reference position signal 9a as shown in FIG. On the other hand, the reference position signal 9a has a different High period (angle) for each cylinder. For example, the pulse of the reference position signal 9a generated when the piston of the first cylinder reaches a predetermined position is different from that of other cylinders. The width is getting wider.
The electronic power distribution circuit 11 discriminates the cylinder in the ignition order from the pulse width of the reference position signal 9a, and outputs the ignition control signals 11a to 11f to the output terminals corresponding to each cylinder. Where 1
1a is a first cylinder ignition control signal, 11b is a second cylinder ignition control signal, and hereinafter, 11f is a sixth cylinder ignition control signal.
The ignition control signals 11a to 11f are low and the ignition coil 3
It is a signal of such a polarity as to energize ~ 8. The ignition control signals 11a to 11f output in this manner are integrated circuits (I
It is input to the ignition output circuit 12 composed of C). The ignition output circuit 12 is a resistor 1 that limits the output current value of the ignition signal.
3, 14 are connected. Further, when a failure of the output is detected, a failure detection pulse signal 12g that generates a pulse signal is connected to the CPU 10. The ignition output circuit 12 outputs ignition signals 12a to 12f of the respective cylinders, which are inverted signals thereof, in response to the ignition control signals 11a to 11f. Here, 12a is a first cylinder ignition signal, 12b is a second cylinder ignition signal, and hereinafter, 12f is a sixth cylinder ignition signal. The output current values of the ignition signals 12a to 12f of the respective cylinders output at this time depend on the resistors 13 and 14, and when the resistance values of 13 and 14 change, the output current also changes.

FIG. 3 is a block diagram showing the internal structure of the ignition output circuit 12 which is the integrated circuit (IC). Ignition control signal 11a for each cylinder input from the electronic power distribution circuit 11
.About.11f are input to the inverters 21 to 26, respectively, and their inverted signals are output from the ignition output circuit 12 as the ignition signals 12a to 12f of the respective cylinders. Ignition signal of each cylinder 12
The currents flowing from a to 12f are supplied from the constant voltage signal 15a generated from the constant voltage power supply 15 via the resistors 13 and 14 connected to the outside of the IC. In the ignition signal output circuit 12, a current is output through the resistor 13 and the ignition signal is 4,
The 5 and 6 cylinder ignition signals 12d, 12e and 12f, and the ignition signals output through the resistor 14 are separated into 1, 2 and 3 cylinder ignition signals 12a, 12b and 12c. On the other hand, the output signal of each cylinder is connected to the failure detection circuit 27 in the IC simultaneously with the output from the terminal to detect whether the output is normal or not. Output failure is identified by the voltage level at the output terminal. If the failure detection circuit 27 detects an abnormality, the failure detection signal 2 output from the failure detection circuit 27 is detected.
A signal is generated at 7a, and this signal is input to the failure detection pulse generation circuit 28. The failure detection pulse generation circuit 28 receives the failure detection signal 27a, shapes the waveform into a signal having a predetermined pulse width, and outputs the failure detection pulse signal 12g to the CPU 1 as a failure detection pulse signal 12g.
Output to 0.

FIG. 4 is a circuit diagram showing an internal circuit of the inverters 21-26. In FIG. 4, the inverter 21 for the 1-cylinder ignition signal 12a will be described. Inverter 21 is P channel
It consists of MOS FET30 and N-channel MOS FET31. 1
The cylinder ignition control signal 11a is connected to the gates of the P channel MOS FET30 and the N channel MOS FET31. The source of the P-channel MOS FET 30 is connected to the resistor 14, and the drain of the P-channel MOS FET 30 is connected to the output terminal of the 1-cylinder ignition signal 12a and the N-channel MOS FE.
It is connected to the drain of T31. N-channel MOS FET3
The source of 1 is configured to be grounded. Now, when the signal level of the 1-cylinder ignition control signal 11a is High, the P-channel MOS FET30 is turned off, the current through the resistor 14 is cut off, and the N-channel MOS FET31 is turned on.
Low is output as the 1-cylinder ignition signal 12a. Conversely 1
When Low is input to the cylinder ignition control signal 11a, the P-channel MOS FET 30 is turned on, and the current is supplied to the 1-cylinder ignition signal 12a via the resistor 14. On the other hand, N channel MO
S FET31 is off at this time, and one cylinder ignition signal 1
High is output to 2a. By the above operation, the cylinder ignition signals 12a to 12f are output.

FIG. 5 is a block diagram showing the internal structure of the failure detection circuit 27. The ignition signals 12a-12f of each cylinder are input to the anodes of the diodes 41-46, respectively. The cathodes of the diodes 41 to 46 are connected to each other, and are connected to the-terminal of the comparator 40 and the pull-down resistor 48. Resistors 47 and 48 are connected to the + terminal of the comparator 40, and the divided voltage of both is connected to the slice level 40b.
Is entered as. Although the resistor 47 is not shown,
It is connected to the power supply signal 15a and is supplied with voltage. In this way, the open detection signal 40c is output from the comparator 40 according to the voltage input to the comparator 40, and is input to the failure detection pulse generation circuit 28. In the failure detection pulse generation circuit 28, the ignition signal 12a of each cylinder is output.
A high level pulse signal is output as the failure detection pulse signal 12g for a predetermined period (for example, 25 mS) from the time when the open detection signal 40a indicating that any one of the signals to 12f is open is input. The fault detection pulse signal 12g is used as the pulse signal for the predetermined period when the CPU 10
This is to ensure that the reading process can be performed twice continuously even when the reading process of the CPU 10 is executed every 10 mS, for example.

FIG. 6 is a timing chart showing the principle of outputting the failure detection pulse signal 12g. Each ignition signal 1
Since 2a to 12f are directly connected to the base of the power transistor 16, the output voltage level of each ignition signal 12a to 12f remains only for the voltage (V _BE ) between the base and emitter of the power transistor 16, so that the output terminal It will be lower than the output voltage when open. In FIG. 6, failure detection is assumed when the output terminal of the 3-cylinder ignition signal 12c is opened. Other cylinder ignition signals 12a, b, d,
Since e and f are normal, the output voltage level becomes low. However, when the output terminal is opened like the cylinder ignition signal 12c, the output voltage level rises to the level of the power supply signal 15a. As described in FIG. 5, each ignition signal 12a-12f
Each signal is synthesized by the diodes 41 to 46,
It is input to the + terminal of the comparator 40. The comparator 40 compares the voltage 40a input to the + terminal with the slice level 40b input to the-terminal. Here, the slice level 40b has a voltage level lower than that of the power supply signal 15a because the power supply signal 15a is divided by the resistors 47 and 48 as described above. On the other hand, the ignition level signal 40a has substantially the same voltage level as the power supply signal 15a when the ignition signal output terminal is open. Therefore, a voltage higher than the slice level 40a of the-terminal is input to the + terminal of the comparator 40, and as a result, the open detection signal 40c is output from the comparator 40. In response to this, the failure detection pulse generation circuit 28 outputs a one-shot pulse having a predetermined pulse width T.

[0013]

With the above construction, an electronic distribution ignition signal output circuit for distributing an ignition signal to each cylinder is integrated circuit (IC).
Can be achieved with. As a result, the amount of heat generated by the limiting resistor that limits the output current of the ignition signal can be suppressed, and the mounting area of the printed board can be reduced.

[Brief description of drawings]

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

FIG. 2 is a timing diagram illustrating the operation of the circuit of FIG.

FIG. 3 is a block diagram showing an internal circuit configuration of an ignition output circuit.

FIG. 4 is an internal circuit diagram of a cylinder ignition signal output inverter.

FIG. 5 is an internal circuit diagram of a failure detection circuit.

FIG. 6 is a timing chart showing the operation of the failure detection circuit.

FIG. 7 is a circuit diagram showing a conventional technique of an electronic distribution ignition signal output circuit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine ignition device, 2 ... Battery, 3 ... 1-cylinder ignition coil, 4 ... 2-cylinder ignition coil, 5 ... 3-cylinder ignition coil, 6 ... 4-cylinder ignition coil, 7 ... 5-cylinder ignition coil, 8
... 6-cylinder ignition coil, 9 ... rotation detector, 9a ... reference position signal, 9b ... angle signal, 10 ... CPU, 10a ... ignition signal, 11 ... electronic distribution circuit, 11a ... 1 cylinder ignition control signal, 11b ... 2 cylinders Ignition control signal, 11c ... 3-cylinder ignition control signal, 11d ... 4-cylinder ignition control signal, 11e ... 5-cylinder ignition control signal, 11f ... 6-cylinder ignition control signal, 12 ...
Ignition output circuit, 12a ... 1 cylinder ignition signal, 12b ... 2 cylinder ignition signal, 12c ... 3 cylinder ignition signal, 12d ... 4 cylinder ignition signal, 12e ... 5 cylinder ignition signal, 12f ... 6 cylinder ignition signal, 12g ... Failure detection Pulse signal, 13 ... Resistance, 1
4 ... Resistor, 15 ... Constant voltage circuit, 15a ... Power supply signal, 16
... power transistor, 21 ... inverter, 22 ... inverter, 23 ... inverter, 24 ... inverter, 25 ...
Inverter, 26 ... Inverter, 27 ... Failure detection circuit,
27a ... Fault detection signal, 28 ... Fault detection pulse generation circuit, 30 ... P-channel MOSFET, 31 ... N-channel MOSFE
T, 40 ... Comparator, 40a ... Ignition level signal, 4
0b ... slice level, 40c ... open detection signal, 4
1 ... Diode, 42 ... Diode, 43 ... Diode, 44 ... Diode, 45 ... Diode, 46 ... Diode, 47 ... Resistance, 48 ... Pulldown resistance, 49 ... Resistance, 50 ... Current limiting resistance, 51 ... Current limiting resistance, 52 …
Current limiting resistance, 53 ... Current limiting resistance, 54 ... Current limiting resistance, 55 ... Current limiting resistance, 60 ... Transistor, 61 ...
Transistor, 62 ... Transistor, 63 ... Transistor, 64 ... Transistor, 65 ... Transistor.

Claims (3)

[Claims] 1. An internal combustion engine having a plurality of cylinders, a sensor group for detecting an operating state of the internal combustion engine, an ignition coil provided in each cylinder of the internal combustion engine, and a power for controlling energization of the ignition coil. In an internal combustion engine ignition device that has a transistor and a CPU that calculates ignition timing and the like based on a signal group from the sensor group, and outputs an ignition signal to the power transistor, the circuit that outputs the ignition signal to the power transistor is the number of cylinders. The internal combustion engine ignition device is characterized in that the output current at the time of outputting the ignition signal is supplied through a resistor connected to the outside of the IC, the integrated circuit (IC) having a minute inverter. 2. The internal combustion engine ignition device according to claim 1, wherein there are a plurality of resistors for supplying the output current, and each resistor supplies a current to a different inverter. 3. The internal combustion engine ignition device according to claim 1, wherein the integrated circuit (IC) has a function of detecting disconnection of a signal line for supplying an ignition signal to the power transistor.