JPS5951676B2 - Automotive internal combustion engine ignition system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ignition device for an internal combustion engine for an automobile, and more particularly to an ignition device that generates a fixed number of sparks within one cycle of the engine regardless of the rotational speed of the engine. be.

Generally, in an ignition system for an internal combustion engine, a pulse signal is generated in proportion to the rotational speed of the engine, and this pulse signal operates an oscillation circuit and other operating circuits to excite a high voltage generation circuit and energize the engine. Generating the desired number of sparks within the cycle.

However, in such an ignition system, as the engine speed increases, the off time of contactor 1 to breaker becomes shorter, so the number of generated pulses decreases proportionally, and at high engine speeds. The disadvantage was that it led to ignition errors.

The present invention has been made in view of the above points, and its purpose is to detect the pulse width of a pulse signal from a signal generator that emits an on/off signal according to the rotation of the engine, and to determine the oscillation cycle of the oscillator. It is an object of the present invention to provide a high-performance ignition device by generating a constant number of sparks within one engine cycle in proportion to the pulse width and in synchronization with the pulse signal of the signal generator.

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 denotes a signal generator having a contactor l-breaker which is turned on and off according to the rotation of the engine.

2 is a waveform shaping circuit that shapes the output voltage signal V1 of the signal generator 1; 3 is a waveform shaping circuit that detects the pulse width of the output voltage signal v2 of the waveform shaping circuit 2, and uses the output voltage signal V3 to adjust the oscillation period of the oscillation circuit 4 as described above. This is an oscillation control circuit that controls in inverse proportion to the pulse width of the signal generator.

5 is activated in synchronization with the rise of the shaped voltage signal v2 from the waveform shaping circuit 2, and is an oscillation output voltage signal V4 of the oscillation circuit 4.
6 is data 1 to 1 from circuit 5.
- It is a switch circuit having a switching element 6a that is turned on and off by the trigger voltage signal v5.

Reference numeral 7 denotes a spark generation circuit that generates a high voltage by operating the switch circuit 6 and generates a spark at the ignition plug of the internal combustion engine.

In the ignition device configured as described above, the oscillation control circuit 3 and the transmission circuit 4 are configured with, for example, a CR oscillator and a magnetoresistive element that changes the frequency by changing the resistance of the CR oscillator, and receives the signal from the waveform signal circuit 2. The resistance of the magneto-resistance element is changed to synchronize with the pulse width T, and a constant pulse is generated regardless of the change in T.

Further, as the oscillation circuit 4, a ring counter, an oscillation circuit using a unijunction transistor, an astable multivibrator, an oscillation circuit using a unijunction transistor, or the like can be used.

Furthermore, the gate circuit 5 can include a differential and integral circuit.

In the ignition system shown in FIG.
When contact 1 to breaker 1a are turned off during the cycle,
As shown in FIG. 2A, a signal voltage v1 is induced from the signal generator 1.

The waveform shaping circuit 2 shapes the waveform of the signal voltage v1 as shown in FIG. 2B and outputs a shaped voltage v2.

The oscillation control circuit 3 generates a signal voltage v1 as shown in FIG.
and a pulse generating circuit that generates a predetermined number of pulse signal voltages V3a during the off period T of the shaping voltage v2, and the pulse signal voltage (3a) is input, and the frequency is controlled during the off period of the pulse signal voltage V3a as shown in the second figure. It consists of a frequency control circuit that outputs an output signal voltage v3.

The oscillation circuit 4 inputs an oscillation output signal v4 as shown in FIG. 2E to the gate circuit 5 in synchronization with the frequency control output voltage V3 output from the oscillation control circuit 3.

As shown in FIG. 2F, the gate circuit 5 is initially driven to convert the signal voltage V1 of the signal generator 1 into data 1 in synchronization with the rise of the waveform shaping circuit 2 (thus, the waveform-shaped voltage signal 2). ~ Signal ■5 is emitted, and thereafter, a game I signal ■5 corresponding to the oscillation signal ■4 from the oscillation circuit 4 is emitted.

In the switch circuit 6, the gate from the gate circuit 5 is
The thyristor 6a is turned on by the ignition signal 5, which causes the spark generation circuit 7 to generate a high voltage and generate a spark from the ignition plug.

In addition, the off time T1 of the signal voltage 1 shown in FIG. , the oscillation frequency of the oscillation circuit 4 increases over time T
The number of sparks increases in inverse proportion to , and a constant number of sparks are always generated within one cycle over the entire engine speed range.

As explained above, the present invention consists of a signal generator having a breaker for contactor 1, a pulse width detection circuit of a waveform shaping circuit that shapes the signal voltage of this signal generator, an oscillation circuit, and a high voltage generation circuit. , after shaping the pulse of the contact breaker, detecting the pulse width and making the oscillation cycle of the oscillation circuit proportional to the pulse width of the signal voltage of the signal generator to cause a certain number of oscillations;
The signal 1 to RIGA is input to the switch circuit in synchronization with the shaped pulse of the contact breaker.

Therefore, according to the present invention, multiple pulse voltages are generated in synchronization with the switching operation of the contactor I/breaker from closed to open, and are supplied to the ignition plug to enable continuous ignition, thereby reducing the amount of carbon monoxide from the engine. There is less occurrence of engine knocking, and knocking caused by a drop in engine output can be eliminated, making it possible to drive a high-performance engine.

Furthermore, since a fixed number of sparks are always generated regardless of the rotational speed of the engine, ignition performance is improved, and engine performance is improved especially when idling.

That is, since a high load is generally not required when the engine is idling, the engine is cold and the temperature of the plug is not optimal.

Also, at high rotation speeds, due to spark propagation speed and other reasons,
It is easy to cause ignition errors, and as a result, carbon adheres to the plug, making it difficult for sparks to fly. As a result, the spark energy decreases and the temperature of the plug cannot be maintained at its optimum level, making it impossible to improve engine performance.

However, according to the present invention, it is possible to supply a constant number of pulses whose pulse width is shortened in proportion to the time T, regardless of changes in the off time T of the signal generator due to changes in the engine speed, and therefore the engine speed is reduced. Since it is possible to always generate a fixed number of sparks regardless of the speed, 1 at low rotation speeds.
The pulse width is long, the pulse energy is large, and the energy supplied to the plug can be made into multiple powerful panel energies.

In addition, since the temperature of the plug increases at high speeds, there is a risk of early ignition if a pulse of the same width as at low speeds is supplied to the plug. Can supply pulses with a width shorter than the pulse width,
Prevents the risk of early ignition.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an ignition system for an internal combustion engine for an automobile according to an embodiment of the present invention, and FIGS. 2A to 2F are voltage waveform diagrams in the ignition system of FIG. 1. 1...Signal generator, 1a...Contact breaker,
2... Waveform shaping circuit, 3... Oscillation control circuit, 4...
-Oscillation circuit, 5...G-1 circuit, 6...Switch circuit, 6a...Zyristor, 7...Spark generation circuit.

Claims (1)

[Scope of Claims] 1. A signal generator that emits a reference signal in accordance with engine rotation, a waveform shaping circuit that shapes the signal voltage of the signal generator, and a waveform shaping circuit that shapes the signal voltage. A transmission control circuit that detects the pulse width of a shaped voltage signal and always outputs a constant control signal regardless of changes in the pulse width; and a transmission circuit that generates a transmission output signal in response to a control output signal of the transmission control circuit. , an initial trigger signal is emitted in synchronization with one rising of the shaping voltage of the waveform shaping circuit, and a plurality of trigger signals at the next stage are turned on and off in response to the output signal of the oscillation circuit to generate a spark in the spark generation circuit. and a switch circuit that generates the signal generator by a fixed number of pulses whose pulse width changes in proportion to the time T, regardless of changes in the off time T of the signal generator due to changes in engine speed. An ignition device for an internal combustion engine for an automobile, characterized in that it always generates a fixed number of sparks in synchronization with a signal voltage. 2 a pulse detection circuit in which the transmission control circuit detects the pulse width of the waveform shaping circuit and generates a pulse voltage signal;
2. The ignition device according to claim 1, further comprising a frequency control circuit which emits a pulse voltage signal having a frequency inversely proportional to the number of cycles of the pulse voltage signal of the pulse detection circuit. 3. The ignition device according to claim 1, wherein the signal generator includes a contact breaker that opens and closes in accordance with the rotation of the engine and generates a reference signal. 4. The ignition device according to claim 1, wherein the switch circuit includes a switching element that is turned on and off by a trigger signal from the gate circuit. 5. The ignition device according to claim 4, wherein the switching element is a thyristor that is turned on by the trigger signal.