JPH05195935A - Contactless ignition device for internal combustion engine - Google Patents

Abstract

PURPOSE:To provide an internal combustion engine contactless ignition device constructed in such a way that the normal and reverse rotation of the engine is discriminated specially at the time of low speed rotation so as to perform high-accuracy ignition control only at the time of normal rotation. CONSTITUTION:The battery changing coils 122, 123 of a magneto generator 11 driven by an internal combustion engine are respectively earthed through resistances 25, 26 to form a loop circuit. An output signal from a sensor 24 for detecting the rotational phase of the generator 11 is supplied to a phase logic judging circuit 27 so that the phase of the detection signal of the sensor 24 is compared with the phase of a current flowing in the loop of the resistances 25, 26 so as to make the transistor 277 of the phase logic judging circuit 27 conductive in the state of the normal rotation of the internal combustion engine being judged. The detection signal from the sensor 24 is supplied to the switching element 217 of an ignition circuit 21 through this transistor 277, and electric charge generated in association with the discharge of an ignition condenser 214 is supplied to an ignition coil 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention can clearly determine the reverse rotation state of an engine, especially at low speed rotation such as at the time of starting,
The present invention relates to a non-contact ignition device for an internal combustion engine in which ignition control is performed smoothly.

[0002]

2. Description of the Related Art In a contactless ignition system for an internal combustion engine,
An ignition command signal is generated based on a detection signal from a sensor that detects the rotational phase of the engine, and an ignition voltage signal is generated in the ignition circuit by the ignition command signal. In this case, since the phase detection signal is generated from the sensor even when the internal combustion engine is rotating in the reverse direction, ignition control may be performed even when the internal combustion engine is rotating in the reverse direction.

When the ignition control is performed during such a reverse rotation of the engine, the reverse rotation phenomenon of the engine continues or ketching occurs. Therefore, the ignition control during the reverse rotation of the engine is stopped. There is a need.

Means for stopping ignition control and causing misfire during such engine reverse rotation is, for example, Japanese Patent Publication No. 51-9.
As disclosed in Japanese Patent Publication No. 084, the engine is normally rotated by utilizing the fact that the phase relationship between the ignition coil for exclusive use of ignition and the sensor for detecting the rotational phase of the engine is different between the normal rotation and the reverse rotation of the engine. The output signal from the sensor is supplied to the ignition control switch circuit only when The ignition control is not executed when the engine is in the reverse rotation state.

However, in recent years, in response to a demand for increasing the output of a vehicle-mounted generator, an ignition device without a generator coil dedicated to CDI (capacitive discharge type ignition system) has been used.

In this case, the phase relationship between the output voltage from the battery charging coil of the generator and the sensor signal is used instead of the ignition-dedicated generating coil. When the engine speed is low, the output voltage from the battery charging coil is low. Therefore, until the generated voltage from the battery charging coil of this generator becomes equal to or higher than the terminal voltage of the battery,
Since no current flows through the charging coil of the generator, the phase logic cannot be determined, and it is necessary to raise the starting rotation speed sufficiently in order to execute reliable start control.

[0007]

The present invention has been made in view of the above points, and it is possible to reliably determine the forward and reverse rotation states of an internal combustion engine even when the engine is running at a low speed. In order to provide a non-contact ignition device for an internal combustion engine, which ensures that the ignition control is stopped at the time of reverse rotation, and in which an accurate ignition control is executed without particularly increasing the starting rotation speed. To do.

[0008]

A non-contact ignition device for an internal combustion engine according to the present invention has a loop circuit in which at least two charging coils of a magneto-generator driven by the internal combustion engine are grounded via respective resistors. Formed, having a power generation phase detection means for detecting the current flowing in the charging coil corresponding to the rotation phase of the magnet type generator, the rotation phase of the magnet type generator is detected by a rotation phase detection sensor, The coincidence between the phase detected by the power generation phase detection means and the phase detected by the rotation phase detection sensor is judged by the logic judgment means. Then, the ignition command signal is given to the switching means of the ignition circuit from the logic determining means of this phase.

[0009]

In the non-contact ignition device for an internal combustion engine configured as described above, the current flowing through the battery charging coil of the generator is controlled by a loop configured by grounding at least two charging coils through resistors. The current phase flowing in this loop is compared with the phase detection signal from the sensor. Here, if there is no loop circuit by the resistance connected to the charging coil, until the generated voltage of the magnet type generator generates sufficient voltage to charge the battery, that is, until the generated voltage becomes equal to or higher than the terminal voltage of the battery. , Although the logic determination of the phase is not performed in the logic determination means, by utilizing the phase of the current flowing in the resistance loop circuit, the phase determination is performed even in the state where the rotation speed of the generator is extremely low, Accurate ignition control is ensured even when the internal combustion engine is rotating at a low speed such as when starting.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration thereof, and a magnet type generator 11 rotatably driven by an internal combustion engine (not shown) includes battery charging coils 121 1, 122 2, 123. The power generation output from the charging coils 121 to 123 is the voltage adjustment circuit 13
This voltage adjustment circuit 13 is supplied to the charging coil.
Diode 130 to rectify the power output from 121 to 123
135, a voltage detecting diode 136, and semiconductor control elements 137 to 139.

The power generated by the generator 11 from the voltage adjusting circuit 13 is supplied to the battery 14 as charging power, and the voltage generated from the battery 14 is passed through the switch 15 to, for example, a lamp. Night load such as 16,
It is supplied to the intermittent load 18 via the switch 17.

The output voltage from the battery 14 is further passed through the switch 19 and the backflow prevention diode 20 to the ignition circuit.
Supplied to 21. A primary coil 221 of the ignition coil 22 is connected to the output side of the ignition circuit 21.
A spark plug 23 is connected to the secondary coil 222 in which the voltage of 1 is induced.

The ignition circuit 21 includes a power supply circuit composed of a resistor 210, a capacitor 211 and a Zener diode 212 to which the output from the diode 20 is supplied, and a DC-DC converter to which the output from the power supply circuit is supplied.
213 is provided, and the charge boosted by the DC-DC converter 213 is rectified by the diode 216 and charged in the ignition capacitor 214. A DC arc diode 215 is connected in series to the ignition capacitor 214, and the charge of the capacitor 214 is controlled to be discharged by a switching element 217 which is a semiconductor control element.

Corresponding to the generator 11, there is provided a phase sensor 24 which generates a signal in synchronization with the rotation of the internal combustion engine. Further, the two charging coils 122 and 123 of the generator 11 are grounded via the resistors 25 and 26, respectively, so that a resistance loop circuit of the charging coils 122 and 123 is formed. Here, the resistors 25 and 26 have high resistance values (equation 1).
0KΩ) is set.

Then, the detection signal from the phase sensor 24 and the terminal voltage of the resistor 25 corresponding to the currents generated in the charging coils 122 and 123 of the generator 11 are the phase logical decision circuit.
It will be supplied to 27.

The phase logic judgment circuit 27 is connected to the power supply of the power supply circuit of the ignition circuit 21 via the resistor 270 and the resistors 270 and 27.
Power is supplied by combining the terminal voltage of 1 and the resistance 25, and this power supply voltage is supplied via the resistance 272 to the comparator.
Supplied to the non-inverting terminal of 273. This terminal is grounded via the parallel circuit of the protective Zener diode 274 and the capacitor 275, and the inverting side terminal of the comparator 273 is set to the ground potential.

The detection signal from the sensor 24 is the diode 27.
It is connected to the emitter of the transistor 277 via 6, and the collector of the transistor 277 is supplied as a gate trigger signal to the semiconductor control element which constitutes the switching element 217 of the ignition circuit 21. And the transistor
The output signal of the comparator 273 is supplied to the base of the 277, and when the output of the comparator 273 becomes low level, the detection signal from the sensor 24 is switched to the switching element 217.
Is output as a trigger signal of the switching element 217 and the switching element 217 is turned on.

In the non-contact ignition device having such a configuration, first, the switch 19 is turned on before the internal combustion engine is started to supply power to the ignition circuit 21 from the battery 14. And
The DC-DC converter 213 is activated to charge the capacitor 214 with the boosted voltage.

Next, when the internal combustion engine is rotated for starting in response to the operation of the ignition switch, the voltage output from the battery charging coils 121 to 123 of the generator 11 rises, and the charging coil 123, the resistor 26, and the resistor 25. The generated current flows in the loop of the charging coil 122 via the. Therefore, the voltage corresponding to the generated current is input to the comparator 273 of the phase logic determination circuit 27, and the output of the comparator 273 is set to the low level.

In this state, when a detection signal is output from the sensor 24 in response to the normal rotation of the engine, this detection signal is supplied to the emitter of the transistor 277 via the diode 276. If the output of the comparator 273 is set to low level at this time, the detection signal from the sensor 24 is supplied to the switching element 217 via the transistor 277 because the transistor 277 is set to the conductive state. .

That is, the switching element 217 is a sensor
The on-control is performed by the detection signal from 24, and the electric charge charged in the ignition capacitor 214 flows into the primary coil 221 of the ignition coil 22 and is boosted by the secondary coil 222 to be supplied to the spark plug 23 to perform the ignition operation. Executed.

Here, when the internal combustion engine is rotating in the reverse direction, the phases of the voltages generated in the charging coils 122 and 123 are inverted, and therefore, the comparator is used at the timing when the detection signal is generated from the sensor 24. The output from 273 goes high. Therefore, at the timing when the detection signal from the sensor 24 rises, the transistor 27
Since 7 is in a non-conducting state, the detection signal from the sensor 24 is not given to the switching element 217 of the ignition circuit 21.

In such an ignition device, the charging coil 12
Considering that 3 is not grounded through resistor 26,
The logic determination circuit of the phase until the generated voltage from the magnet generator 11 is rotated at a voltage required to charge the battery 14, specifically, at a rotation speed that is equal to or higher than the terminal voltage of the battery 14.
No logic judgment operation is performed at 27. Therefore, as in the case of reverse rotation, the switching element 21 of the ignition circuit 21
The trigger signal is not given to 5, and a misfire occurs. For example, the speed of rotation of a normal internal combustion engine is 150 rpm to 20 rpm.
If it is 0 rpm, this is 600 rpm to 900 rpm.
Must be set to rise.

[0024]

As described above, according to the non-contact ignition device for an internal combustion engine according to the present invention, even when the engine speed is very low such as when the internal combustion engine is started, the reverse rotation state of the engine is maintained. The ignition signal generation control is executed based on the phase detection signal from the sensor only when the rotation speed is positively determined. Therefore, highly reliable ignition control is performed especially at low speed rotation.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram illustrating a contactless ignition device for an internal combustion engine according to an embodiment of the present invention.

[Explanation of symbols]

11 ... Magnetic generator, 121-123 ... Battery charging coil,
13 ... Voltage adjusting circuit, 14 ... Battery, 19 ... Switch, 21 ...
Ignition circuit, 213 ... DC-DC converter, 214 ... Ignition capacitor, 217 ... Switching element, 22 ... Ignition coil, 23 ... Spark plug, 24 ... Sensor, 25, 26 ... Resistor, 27 ... Phase logic determination circuit, 273 ... Comparator, 277 ... Transistor.

Claims (1)

[Claims] 1. A magnet type generator driven by an internal combustion engine, and at least two charging coils of the magnet type generator are grounded through resistors to form a loop circuit, and the rotation of the magnet type generator is performed. A power generation phase detection means for detecting a current flowing through the charging coil in accordance with a phase, a rotation phase detection sensor corresponding to a rotation phase of the magnet type generator, a phase detected by the power generation phase detection means, and The phase detected by the rotational phase detection sensor is compared with the phase logical judgment means for judging the coincidence, and the generated power from the magnet type generator is supplied to the switching means operated based on the ignition command signal. An ignition circuit that supplies an ignition voltage signal to the spark plug in response to an operation, and an ignition command signal is given from the phase logic determination means to the switching means of the ignition circuit. Contactless ignition system for an internal combustion engine, characterized in that the way.