JP6796989B2 - Ignition system for internal combustion engine - Google Patents

Description

The present invention relates to an ignition device for an internal combustion engine.

As a conventional ignition device for an internal combustion engine, as described in Patent Document 1, there is one provided with an ignition coil unit having a built-in current cutoff type ignition device for each cylinder of the internal combustion engine.

The current cutoff type ignition device cuts off the primary current of the ignition coil and generates a high voltage, which is a large transfer power, on the primary side of the ignition coil, thereby further generating on the secondary side of the ignition coil. Due to a large high voltage, a high-voltage spark discharge is generated between the electrodes of the ignition plug to generate a flame nucleus between the electrodes, and a small-voltage heat-retaining discharge following the spark discharge is generated to generate the flame nucleus. Grow. The above-mentioned spark discharge of the current cutoff type ignition device causes a flame nucleus generated or growing between the electrodes of the spark plug to become a heat source and ignite the air-fuel mixture existing around the spark plug in the combustion chamber of the cylinder. It is a thing.

However, in the ignition device for an internal combustion engine described in Patent Document 1, a CDI ignition device as an auxiliary circuit for spark discharge is arranged outside the ignition coil unit. The CDI ignition device has an auxiliary capacitor for spark discharge, and the above-mentioned sparks are adjusted to the timing when the current cutoff type ignition device cuts off the primary current of the ignition coil and generates a high voltage on the secondary side of the ignition coil. The high-pressure capacitor voltage accumulated in the discharge auxiliary capacitor is applied to the primary side of the ignition coil in the ignition coil unit during spark discharge as the spark discharge auxiliary voltage.

In the ignition device for an internal combustion engine described in Patent Document 1, the high voltage generated on the primary side of the ignition coil by the operation of the current cutoff type ignition device and the high voltage of the high voltage stored in the auxiliary condenser for spark discharge of the CDI ignition device. Is added so as to be superposed as an auxiliary voltage for spark discharge, and a larger secondary high voltage is generated on the secondary side of the ignition coil. Therefore, in addition to the spark discharge by the current cutoff type ignition device, a large ignition energy is emitted between the electrodes of the ignition coil by superimposing the capacitance discharge of the CDI ignition device. This causes a higher voltage discharge between the electrodes of the ignition coil than a normal spark discharge, promotes the growth of the initial stage of flame nucleation between the electrodes, and exists around the spark plug. It is intended to improve the ignitability of the air-fuel mixture.

Japanese Unexamined Patent Publication No. 2001-41136

The ignition device for an internal combustion engine described in Patent Document 1 employs a composite dielectric system in which a capacitance discharge by a CDI ignition device is added to a spark discharge by a current cutoff type ignition device.

However, the combined discharge method described in Patent Document 1 adds only one capacitance discharge to the spark discharge by the current cutoff type ignition device, and increases the total amount of ignition energy released between the electrodes of the spark plug. There is a limit to the continuation of heat supply.

Further, in the ignition device for an internal combustion engine, it is desirable to reduce the consumption of the electrodes of the spark plug even when increasing the total amount of ignition energy released between the electrodes of the spark plug and continuing the heat supply. Is done.

An object of the present invention is to improve the ignition performance of an air-fuel mixture by a spark plug in an ignition device for an internal combustion engine.

Another object of the present invention is to reduce the consumption of the electrodes of the spark plug in the ignition device for an internal combustion engine.

The invention according to claim 1 uses an ignition coil unit having a built-in current cutoff type ignition device, and the current cutoff type ignition device cuts off the primary current of the ignition coil to send a large transmission power to the primary side of the ignition coil. By generating a high voltage, a higher high voltage generated on the secondary side of the ignition coil causes a high voltage spark discharge between the electrodes of the ignition plug to generate a flame nucleus between the electrodes. In addition, it is an ignition device for an internal combustion engine that generates a small voltage heat-retaining discharge following the spark discharge to grow the flame nucleus, has an auxiliary capacitor for spark discharge, and accumulates in the auxiliary capacitor for spark discharge. It has an auxiliary circuit for spark discharge that is added to the primary side of the ignition coil in the ignition coil unit during spark discharge, and one or more auxiliary capacitors for heat retention discharge, using a high-voltage capacitor voltage as an auxiliary voltage for spark discharge. Auxiliary circuit for heat-retaining discharge and an auxiliary circuit for spark discharge that are applied to the primary side of the ignition coil in the ignition coil unit during heat-retaining discharge by using the capacitor voltage accumulated in the auxiliary capacitor for heat-retaining discharge as the auxiliary voltage for heat-retaining discharge. It is configured to have a discharge control circuit that controls an auxiliary circuit for heat retention and discharge, and the discharge control circuit includes the presence or absence of an auxiliary voltage for spark discharge and the voltage of the auxiliary voltage for spark discharge according to the operating conditions of the internal combustion engine. At least one of the control target items including the setting of, whether or not the auxiliary voltage for heat retention and discharge is added, the setting of the auxiliary voltage for heat retention and discharge, and the number of times the auxiliary voltage for heat retention and discharge is added can be controlled . Further, it has a trigger circuit that detects the generation timing of a high voltage by the current cutoff type ignition device of the ignition coil unit as a discharge timing, and the discharge control circuit assists for spark discharge based on the discharge timing detected by the trigger circuit. The output element of the auxiliary voltage for spark discharge by the circuit and the output element of the auxiliary voltage for heat retention and discharge by the auxiliary circuit for heat retention and discharge are output and operated .

The invention according to claim 2 is the invention according to claim 1, further, the discharge control circuit is such that the target value of the control target item is transmitted from the outside to control the control target item.

The invention according to claim 3 is the invention according to claim 1, further, the discharge control circuit transmits the operating condition of the internal combustion engine, calculates the target value of the controlled item based on the operating condition, and said the invention. It is designed to control the items to be controlled.

The invention according to claim 4 further provides an ignition coil unit in each of a plurality of cylinders in the invention according to any one of claims 1 to 3 , and each single spark discharge shared by the ignition coil unit of each cylinder. It is designed to have an auxiliary circuit for heat retention and discharge and an auxiliary circuit for heat retention and discharge.

(Claim 1)
(a) The ignition device for an internal combustion engine not only adds a capacitance discharge by an auxiliary circuit for spark discharge during a spark discharge by a current cutoff type ignition device, but also a heat retention discharge during a heat retention discharge by a current cutoff type ignition device. It will add capacitance discharge by the auxiliary circuit.

By adding a capacitance discharge by the auxiliary circuit for spark discharge during the spark discharge by the current cutoff type ignition device, the growth of the initial stage of the generation of flame nuclei between the electrodes of the spark plug is promoted, and the ignitability by the spark plug is improved. In addition to the improvement, by adding the capacitance discharge by the heat retention discharge auxiliary circuit even during the heat retention discharge by the current cutoff type ignition device, ignition is performed even at the stage of flame nuclear growth in which the discharge continues in the spark discharge or the heat retention discharge. A high temperature is generated between the electrodes of the plug to keep the air-fuel mixture warm, and the ignitability of the spark plug is further improved.

That is, in the process of spark discharge or heat retention discharge in the spark plug, the total amount of ignition energy released between the electrodes of the spark plug is increased and the heat supply is continued, and the ignition performance of the air-fuel mixture by the spark plug is improved. It will be possible.

(b) In the above-mentioned (a), the discharge control circuit sets the presence or absence of the auxiliary voltage for spark discharge, the setting of the auxiliary voltage for spark discharge, and the addition of the auxiliary voltage for heat retention discharge according to the operating condition of the internal combustion engine. Controls at least one of the control target items including the presence / absence of, the setting of the auxiliary voltage for heat retention / discharge, and the number of times the auxiliary voltage for heat retention / discharge is applied.

That is, improvement of torque performance in the low to medium speed range of the internal combustion engine, improvement of the response performance of the number of rotations to the accelerator operation of the internal combustion engine, reliable ignition under high supercharging pressure in a turbo vehicle, improvement of startability of the tuning engine. When trying to stabilize idling, etc., the discharge control circuit is used to add capacity discharge by the spark discharge auxiliary circuit and capacity discharge by the heat retention discharge auxiliary circuit described in (a) above, and to operate those internal combustion engines. It can be positively strengthened according to the situation, and the ignition performance of the air-fuel mixture by the spark plug can be surely improved.

On the other hand, in an internal combustion engine, in an operating situation where it is not necessary to significantly improve the ignition performance of the air-fuel mixture by the spark plug, the discharge control circuit adds capacitance discharge by the spark discharge auxiliary circuit described in (a) above and keeps the heat warm. Limits or suspends the addition of capacitance discharge by the discharge auxiliary circuit. As a result, it is possible to reduce the consumption of the electrodes of the spark plug due to the addition of the capacitance discharge by the auxiliary circuit for spark discharge and the addition of the capacitance discharge by the auxiliary circuit for heat retention discharge.
(c) The ignition device for an internal combustion engine has a trigger circuit that detects the generation timing of a high voltage by the current cutoff type ignition device of the ignition coil unit as the discharge timing. Then, the discharge control circuit outputs an output element of the auxiliary voltage for spark discharge by the auxiliary circuit for spark discharge and an output element of the auxiliary voltage for heat retention discharge by the auxiliary circuit for heat retention discharge based on the discharge timing detected by the trigger circuit. By operating, the above-mentioned (a) addition of capacitance discharge by the auxiliary circuit for spark discharge and addition of capacitance discharge by the auxiliary circuit for heat retention discharge are executed.

(Claim 2)
(d) In the control operation of (b) above, the discharge control circuit can control the control target item by transmitting the target value of the control target item from the outside.

(Claim 3)
(e) In the control operation of (b) above, the discharge control circuit can transmit the operating status of the internal combustion engine, calculate the target value of the controlled target item based on the operating status, and control the controlled target item. ..

(Claim 4 )
(f) The ignition device for an internal combustion engine is provided with an ignition coil unit for each of a plurality of cylinders, and has a single spark discharge auxiliary circuit and a heat retention discharge auxiliary circuit shared by the ignition coil units of each cylinder. .. Therefore, each single spark discharge auxiliary circuit and heat retention discharge auxiliary circuit correspond to the ignition coil unit of all cylinders, the number of parts can be reduced, and a plurality of spark discharge auxiliary circuits and heat retention discharge auxiliary circuits can be reduced. It is possible to eliminate wasteful power consumption during standby as compared with the case where is provided for each ignition coil unit of each cylinder.

FIG. 1 is a schematic view showing an ignition device for an internal combustion engine. FIG. 2 is a schematic diagram showing a voltage waveform generated on the primary side of the ignition coil by the current cutoff type ignition device. FIG. 3 is a schematic diagram showing each voltage waveform of the spark discharge auxiliary voltage and the heat retention discharge auxiliary voltage added to the primary side of the ignition coil by the spark discharge auxiliary circuit and the heat retention discharge auxiliary circuit. FIG. 4 is a schematic view showing a multi-spark circuit of the first embodiment including an auxiliary circuit for spark discharge and an auxiliary circuit for heat retention discharge. FIG. 5 is a schematic diagram showing a multi-spark circuit of the second embodiment including an auxiliary circuit for spark discharge and an auxiliary circuit for heat retention discharge.

(Example 1) (FIGS. 1 to 4)
(Ignition coil unit 10)
As shown in FIG. 1, the ignition device 100 for an internal combustion engine of the present embodiment includes an ignition coil unit 10 incorporating a current cutoff type ignition device 11 and an ignition coil 12. The ignition coil unit 10 includes a battery 13 and a spark plug 14 in addition to the current cutoff type ignition device 11 and the ignition coil 12.

The ignition coil unit 10 is arranged corresponding to the cylinder of the internal combustion engine (one cylinder in the case of a single-cylinder engine, each cylinder in the case of a multi-cylinder engine), and the engine control unit (ECU) 1 provides a current consisting of, for example, a transistor. The cutoff ignition device 11 is controlled to be on (conducting state) / off (non-conducting state).

That is, the current cutoff type ignition device 11 is normally in the off state. Then, when the timing of spark discharge in the ignition coil unit 10 corresponding to the cylinder having the internal combustion engine approaches, the engine control unit 1 switches the current cutoff type ignition device 11 from the off state to the on state, and the current cutoff type ignition device 11 Is held in the on state for the closing angle (dwell angle) C. Next, when the engine control unit 1 turns off the current cutoff type ignition device 11, the current cutoff type ignition device 11 cuts off the primary current of the ignition coil 12 and causes a large countercurrent force to the primary side of the ignition coil 12. A certain primary high voltage is generated, and a larger secondary high voltage is generated on the secondary side of the ignition coil 12.

Here, if the voltage waveform generated by the current cutoff type ignition device 11 of the ignition coil unit 10 on the primary side of the ignition coil 12 is schematically shown, as shown in FIG. 2 (time on the horizontal axis and voltage on the vertical axis). Become. In FIG. 2, VA indicates a large voltage VA generated on the primary side of the ignition coil 12 at the moment when the current cutoff type ignition device 11 is turned off, and the high-density energy stored in the ignition coil 12 by this large voltage VA ignites. A large voltage corresponding to the spark discharge A is generated between the electrodes of the spark plug 14 transmitted to the plug 14, and a flame nucleus is generated between the electrodes. VB indicates a small voltage VB generated on the primary side of the ignition coil 12 following the generation of a large voltage VA due to the off of the current cutoff type ignition device 11, and the energy stored in the ignition coil 12 by this small voltage VB is the ignition plug. A small voltage (glow discharge) corresponding to the heat retention discharge B is transmitted between the electrodes of the ignition plug 14 and is followed by a large voltage corresponding to the above-mentioned spark discharge A and a large voltage corresponding to the spark discharge A. (Also called) is generated to grow the flame nucleus.

In FIG. 2, C is the time during which the ignition coil 12 is energized, and is referred to as the above-mentioned closing angle (dwell angle). Energy is accumulated in the ignition coil 12 by energization at the closed angle C, and a primary high voltage (large voltage VA), which is a counter electromotive force, is generated on the primary side of the ignition coil 12 at the timing when the energization is turned off. ..

(Multi-spark circuit 20)
The ignition device 100 for an internal combustion engine has a multi-spark circuit 20 arranged outside the ignition coil unit 10. The multi-spark circuit 20 is connected to the primary side of the ignition coil 12 in the ignition coil unit 10, the current cutoff type ignition device 11 cuts off the primary current of the ignition coil 12, and a high voltage is generated in the ignition coil 12. The timing is detected as the discharge timing, and in accordance with this discharge timing, as shown in FIG. 3, the auxiliary voltage EA for spark discharge and the auxiliary voltage EB for heat retention discharge (EB1 to EB3 in this embodiment) are on the primary side of the ignition coil 12. ) Is added.

As shown in FIG. 4, the multi-spark circuit 20 includes a trigger circuit 30, a discharge control circuit 40, a spark discharge auxiliary circuit 50 that outputs a spark discharge auxiliary voltage EA, and a heat retention that outputs a heat retention discharge auxiliary voltage EB. It has a discharge auxiliary circuit 60.

In this embodiment, it is assumed that the internal combustion engine has a plurality of cylinders. Along with this, in the ignition device 100 for an internal combustion engine of the present embodiment, the ignition coil units 10 are arranged in each of the plurality of cylinders, and the ignition coil units 10 have a single multi-spark circuit 20 common to them. It is said. The multi-spark circuit 20 has a trigger circuit 30 corresponding to the ignition coil unit 10 of each cylinder, and has a discharge control circuit 40 common to the ignition coil unit 10 of each cylinder. Further, the multi-spark circuit 20 is configured to include each single spark discharge auxiliary circuit 50 and a heat retention discharge auxiliary circuit 60 shared by the ignition coil unit 10 of each cylinder.

The multi-spark circuit 20 is connected to the energizing wires 15 connected to the primary side (ignition output 1 ... ignition output N) of the ignition coils 12 in the ignition coil unit 10 of each cylinder and the ignition coils 12 of those energizing wires 15. A single energizing wire 16 that connects the ends opposite to the connected side to each other, an energizing wire 17 that connects the output end of the spark discharging auxiliary capacitor 52 in the spark discharging auxiliary circuit 50 to the electric wire 16, and a heat retaining discharge. The auxiliary circuit 60 includes an energizing wire 18 that connects the output end of the heat-retaining and discharging auxiliary capacitor 62 to the electric wire 16.

(Trigger circuit 30)
The trigger circuit 30 is provided so as to correspond to each ignition coil unit 10 of each cylinder, and is directly connected to the primary side of the ignition coil 12 in each ignition coil unit 10 via an energizing wire 15, and is a current cutoff type ignition. The device 11 cuts off the primary current of the ignition coil 12, detects the timing at which a high voltage is generated in the ignition coil 12 as the discharge timing, and transmits this detection result to the discharge control circuit 40 by each signal line 31.

(Discharge control circuit 40)
The discharge control circuit 40 (CPU) is connected to each main output element 41 interposed in each energizing line 15 by a signal line 41L. The discharge control circuit 40 detects the discharge timing of the ignition coil unit 10 corresponding to each trigger circuit 30, and at the same time, turns on (conducts) each of the main output elements 41 continuously for a certain period of time.

The discharge control circuit 40 is connected to the output element 42 of the auxiliary voltage EA for spark discharge, which is interposed in the energizing line 17, by the signal line 42L. The discharge control circuit 40 turns on the main output element 41 in response to each trigger circuit 30 detecting the discharge timing of each ignition coil unit 10, or after a certain period of time has elapsed after the output element 41 is turned on, the CPU The output element 42 is turned on (conducting state) at the timing set by the internal arithmetic circuit and data.

As a result, the discharge control circuit 40 uses the capacitor voltage accumulated in the spark discharge auxiliary capacitor 52 of the spark discharge auxiliary circuit 50 as the spark discharge auxiliary voltage EA as the ignition coil 12 in the ignition coil unit 10 during spark discharge. It is added to the primary side of.

The discharge control circuit 40 is connected to the output element 43 of the heat-retaining discharge auxiliary voltage EB interposed in the energizing line 18 by the signal line 43L. The discharge control circuit 40 turns on the main output element 41 and the output element 42 in response to each trigger circuit 30 detecting the discharge timing of each ignition coil unit 10, and then turns on the output element 42 for a certain period of time. After the lapse of time, the output element 43 is turned on (conducting state) at a timing set by the arithmetic circuit and data inside the CPU.

In the present embodiment, the discharge control circuit 40 has a plurality of electric wires that connect the output ends of the plurality of heat-retaining and discharging auxiliary capacitors 62-1, 62-2, ... The heat-retaining and discharging auxiliary circuits 60 to the electric wire 16. Each of the energizing wires 18-1, 18-2 ... Is provided with a plurality of output elements 43-1, 43-2 ..., And each of the output elements 43-1, 43-2 ... Is turned on (conducting) in order. State).

As a result, the discharge control circuit 40 uses the capacitor voltage accumulated in each of the heat-retaining and discharging auxiliary capacitors 62 (62-1, 62-2 ...) of the heat-retaining and discharging auxiliary circuit 60 as the heat-retaining and discharging auxiliary voltage EB (EB-). 1, EB-2 ...) Are added to the primary side of the ignition coil 12 in the ignition coil unit 10 during the heat-retaining discharge a plurality of times in order.

(Auxiliary circuit 50 for spark discharge)
The spark discharge auxiliary circuit 50 has a DC / DC converter circuit 51 and a spark discharge auxiliary capacitor 52, and the high voltage capacitor voltage accumulated in the spark discharge auxiliary capacitor 52 by the DC / DC converter circuit 51 is used for spark discharge. As an auxiliary voltage EA, a large voltage VA having a primary high voltage generated on the primary side of the ignition coil 12 in the ignition coil unit 10 during spark discharge due to the operation of the current cutoff type ignition device 11 in the ignition coil unit 10. , Add so that they overlap.

The DC / DC converter circuit 51 is a DC / DC control IC51A (the switching frequency is, for example, 100 KHz, the output voltage in the spark discharge region is, for example, 400 V, and the voltage can be changed by the discharge control circuit 40), and the switching FET 51B. The current detection circuit 51C for current control and the voltage detection circuit 51D for voltage control are included. The DC / DC converter circuit 51 boosts, for example, a 12V voltage supplied by the ignition power supply 101 to, for example, DC400V.

The spark discharge auxiliary capacitor 52 is composed of one capacitor and is accompanied by a rectifying diode 52A. The ignition / discharging auxiliary capacitor 52 has a capacitance of, for example, 0.5 to 1.0 μF, and charges the output voltage of the DC / DC converter circuit 51.

(Auxiliary circuit 60 for heat retention and discharge)
The heat-retaining / discharging auxiliary circuit 60 has a DC / DC converter circuit 61 and a plurality of heat-retaining / discharging auxiliary capacitors 62 (62-1, 62-2 ...) (However, there is only one heat-retaining / discharging auxiliary circuit 60. It may have only the auxiliary capacitor 62 for heat retention and discharge). The heat-retaining / discharging auxiliary circuit 60 uses the capacitor voltage accumulated in the heat-retaining / discharging auxiliary capacitors 62 (one or a plurality of capacitors 62-1, 62-2 ...) by the DC / DC converter circuit 61 as the heat-retaining / discharging auxiliary voltage EB. As (EB-1, EB-2 ...), the primary side generated on the primary side of the ignition coil 12 in the ignition coil unit 10 during heat retention discharge by the operation of the current cutoff type ignition device 11 in the ignition coil unit 10. It is added in order so as to be superimposed on the high voltage and small voltage VB.

The DC / DC converter circuit 61 is a DC / DC control IC61A (the switching frequency is, for example, 100 KHz, the output voltage in the heat-retaining discharge region is, for example, 100 to 200 V, and the voltage can be changed by the discharge control circuit 40), switching. The FET 61B, the current detection circuit 61C for current control, and the voltage detection circuit 61D for voltage control are included. The DC / DC converter circuit 61 boosts, for example, a 12V voltage supplied by the ignition power supply 101 to, for example, DC100 to 200V.

The discharge control circuit 40 makes it possible to change the output voltage of the DC / DC converter circuit 61 via the control voltage variable circuit 44.

As described above, the heat-retaining discharge auxiliary capacitor 62 is composed of a plurality of capacitors 62-1, 62-2 ..., And is accompanied by a rectifying diode 62A. Each heat-retaining and discharging auxiliary capacitor 62 (62-1, 62-2 ...) has a capacity of, for example, 0.1 to 0.5 μF, and charges the output voltage of the DC / DC converter circuit 61.

Therefore, the ignition operation by the ignition device 100 for the internal combustion engine is performed as follows.
(1) In the trigger circuit 30 corresponding to each ignition coil unit 10 of each cylinder, the current cutoff type ignition device 11 of the ignition coil unit 10 cuts off the primary current of the ignition coil 12, and the ignition coil 12 has a high voltage. Is detected as the discharge timing. This detection result of each trigger circuit 30 is transmitted to the discharge control circuit 40.

At this time, in the ignition coil unit 10 of each cylinder, the current cutoff type ignition device 11 cuts off the primary current of the ignition coil 12, and a high voltage which is a large countercurrent force is applied to the primary side of the ignition coil 12. Is generated, a larger high voltage is generated on the secondary side of the ignition coil 12, a large voltage corresponding to spark discharge A is generated between the electrodes of the ignition plug 14, and a flame nucleus is generated between the electrodes. In addition, the flame nucleus is grown by generating a large voltage corresponding to the spark discharge A and a small voltage corresponding to the heat retaining discharge B as compared with the large voltage corresponding to the spark discharge A. ..

(2) The discharge control circuit 40 detects the discharge timing of the corresponding ignition coil unit 10 by each trigger circuit 30, and at the same time, the energizing wire 15 connected to the primary side of the ignition coil 12 in the ignition coil unit 10. The main output element 41 interposed therein is continuously turned on (conducting state) for a certain period of time.

In the main output element 41, the ignition coil 12 in the ignition coil unit 10 generates a large voltage corresponding to the spark discharge A of the above-mentioned (1) and a small voltage corresponding to the heat retaining discharge B between the electrodes of the spark plug 14. It is continuously turned on (conducting state) for a certain period of time.

(3) The discharge control circuit 40 is the output element 42 interposed in the energizing wire 17 at the same time as the main output element 41 is turned on according to (2) above, or after a certain period of time has elapsed after the main output element 41 is turned on. On (conducting state)

When the output element 42 is turned on (conducting state), the capacitor voltage accumulated in the spark discharge auxiliary capacitor 52 of the spark discharge auxiliary circuit 50 becomes the spark discharge auxiliary voltage EA, and the spark discharge is performed in (1) above. It is added so as to be superimposed on the primary high voltage (large voltage VA) generated on the primary side of the ignition coil 12 in the ignition coil unit 10 inside (FIG. 3).

(4) The discharge control circuit 40 is interposed in each of a plurality of energizing wires 18 (18-1, 18-2 ...) after a certain period of time has elapsed after the output element 42 is turned on according to (2) above. Each of the output elements 43 (43-1, 43-2 ...) Is turned on (conducting state) in order. When each output element (43-1, 43-2 ...) Is turned on (conducting state) in order, each of the plurality of heat-retaining / discharging auxiliary capacitors 62-1, 62-2 ... The capacitor voltage accumulated in the above-mentioned is generated on the primary side of the ignition coil 12 in the ignition coil unit 10 during the heat-retaining discharge in the above-mentioned (1) as the auxiliary voltages EB-1 and EB-2 for heat-retaining discharge. It is added so as to be superimposed on the primary high voltage (small voltage VB) (Fig. 3).

Therefore, according to the ignition device 100 for an internal combustion engine, the presence of the multi-spark circuit 20 exerts the following action and effect (a).
(a) The internal combustion engine ignition device 100 not only adds a capacitance discharge by the spark discharge auxiliary circuit 50 during the spark discharge by the current cutoff type ignition device 11, but also during the heat retention discharge by the current cutoff type ignition device 11. Also, a plurality of capacitance discharges are added by the heat-retaining discharge auxiliary circuit 60.

By adding a capacitance discharge by the spark discharge auxiliary circuit 50 during the spark discharge by the current cutoff type ignition device 11, the growth of the initial stage of flame nucleation between the electrodes of the spark plug 14 is promoted, and the spark plug 14 By adding a plurality of capacitance discharges by the heat retention discharge auxiliary circuit 60 even during the heat retention discharge by the current cutoff type ignition device 11, the discharge continues in the spark discharge or the heat retention discharge. Even in the stage of flame nucleus growth, a high temperature is generated between the electrodes of the spark plug 14 to continue warming the air-fuel mixture, and the ignitability of the spark plug 14 is further improved.

That is, in the process of spark discharge or heat retention discharge in the spark plug 14, the total amount of ignition energy released between the electrodes of the spark plug 14 is increased and the heat supply is continued, and the air-fuel mixture is ignited by the spark plug 14. The performance can be improved.

The heat-retaining / discharging auxiliary circuit 60 may have only one heat-retaining / discharging auxiliary capacitor 62. In that case, the heat-retaining is described in (4) above, which describes the ignition operation of the internal combustion engine ignition device 100. The capacitor voltage accumulated in one heat-retaining discharge auxiliary capacitor 62 (capacitor 62-1) of the discharge auxiliary circuit 60 is used as the heat-retaining discharge auxiliary voltage EB (EB-1) during heat-retaining discharge in (1) above. It is added so as to be superimposed on the above-mentioned primary high voltage (small voltage VB) generated on the primary side of the ignition coil 12 in the ignition coil unit 10.

However, in the ignition device 100 for an internal combustion engine, in the process of spark discharge or heat retention discharge in the spark plug 14, the presence of the multi-spark circuit 20 increases the total amount of ignition energy released between the electrodes of the spark plug 14, and heat is generated. As a result, the electrodes of the spark plug 14 may be violently attacked by a discharge energy larger than usual and consumed more than usual because the supply is continued. Therefore, the ignition device 100 for an internal combustion engine has the following configuration in order to reduce the consumption of the electrodes of the spark plug 14.

That is, when controlling the spark discharge auxiliary circuit 50 and the heat retention discharge auxiliary circuit 60, the discharge control circuit 40 determines whether or not the spark discharge auxiliary voltage EA is added and the spark discharge auxiliary according to the operating condition of the internal combustion engine. Controls at least one of the control target items including the setting of the voltage EA, the presence / absence of the auxiliary voltage EB for heat retention / discharge, the setting of the auxiliary voltage EB for heat retention / discharge, and the number of times the auxiliary voltage EB for heat retention / discharge is added. To do.

The discharge auxiliary circuit 40 transmits the target value of the control target item from the external controller 110 and controls the control target item. That is, the external controller 110 is, for example,
i. For example, when a vehicle equipped with an internal combustion engine is running in a race, the addition of capacity discharge by the spark discharge auxiliary circuit 50 and the addition of capacity discharge by the heat retention discharge auxiliary circuit 60 as described in (a) above should be positively strengthened. , The auxiliary circuit 50 for spark discharge, and the auxiliary circuit 60 for heat retention discharge are controlled.
ii. For example, during general driving of a vehicle equipped with an internal combustion engine, the addition of capacity discharge by the spark discharge auxiliary circuit 50 and the addition of capacity discharge by the heat retention discharge auxiliary circuit 60 described in (a) above are restricted or suspended. In addition, the auxiliary circuit 50 for spark discharge and the auxiliary circuit 60 for heat retention discharge are controlled.

Therefore, according to the ignition device 100 for an internal combustion engine, in addition to the above-mentioned effects (a), the following effects (b) to (e) are exhibited.

(b) In the above-mentioned (a), the discharge control circuit 40 determines whether or not the auxiliary voltage EA for spark discharge is added and the auxiliary voltage EA for spark discharge is added according to the operating condition of the internal combustion engine transmitted by the external controller 110. Controls at least one of the control target items including the setting of the voltage, the presence / absence of the addition of the auxiliary voltage EB for heat retention / discharge, the setting of the voltage of the auxiliary voltage EB for heat retention / discharge, and the number of times the auxiliary voltage EB for heat retention / discharge is added.

That is, when the vehicle transmitted by the external controller 110 is running, for example, in a race, the torque performance of the internal combustion engine in the low to medium speed range is improved, the response performance of the rotation speed to the accelerator operation of the internal combustion engine is improved, and the turbo vehicle is high. In order to ensure reliable ignition under supercharging pressure, improve the startability of the tuning engine, stabilize idling, etc., the discharge control circuit 40 adds capacitance discharge by the spark discharge auxiliary circuit 50 described in (a) above. The addition of capacitance discharge by the heat-retaining discharge auxiliary circuit 60 can be positively strengthened according to the operating conditions of those internal combustion engines, and the ignition performance of the air-fuel mixture by the spark plug 14 can be reliably improved.

On the other hand, in an operating situation where it is not necessary to remarkably improve the ignition performance of the air-fuel mixture by the spark plug 14 in the internal combustion engine, such as during general running of the vehicle transmitted by the external controller 110, the discharge control circuit 40 is used. The above-mentioned (a), the addition of the capacitance discharge by the spark discharge auxiliary circuit 50 and the addition of the capacitance discharge by the heat retention discharge auxiliary circuit 60 are restricted or suspended. As a result, the consumption of the electrode of the spark plug 14 due to the addition of the capacitance discharge by the spark discharge auxiliary circuit 50 and the addition of the capacitance discharge by the heat retention discharge auxiliary circuit 60 can be reduced.

(c) The discharge control circuit 40 can control the control target item by transmitting the target value of the control target item from the outside in the control operation of the above (b).

(d) The ignition device 100 for an internal combustion engine has a trigger circuit 30 that detects the generation timing of a high voltage by the current cutoff type ignition device 11 of the ignition coil unit 10 as a discharge timing. Then, the discharge control circuit 40 is based on the discharge timing detected by the trigger circuit 30, the output element 42 of the spark discharge auxiliary voltage EA by the spark discharge auxiliary circuit 50, and the heat retention discharge auxiliary by the heat retention discharge auxiliary circuit 60. By operating the output element 43 of the voltage EB for output operation, the above-mentioned (a) addition of capacitance discharge by the spark discharge auxiliary circuit 50 and addition of capacitance discharge by the heat retention discharge auxiliary circuit 60 are executed.

(e) The ignition device 100 for an internal combustion engine is provided with ignition coil units 10 in each of a plurality of cylinders, and each single spark discharge auxiliary circuit 50 and heat retention discharge auxiliary shared by the ignition coil units 10 of each cylinder. It has a circuit 60. Therefore, each single spark discharge auxiliary circuit 50 and heat retention discharge auxiliary circuit 60 correspond to the ignition coil unit 10 of all cylinders, the number of parts can be reduced, and a plurality of spark discharge auxiliary circuits 50 and heat retention auxiliary circuit 50 and heat retention. Compared with the case where the discharge auxiliary circuit 60 is provided for each ignition coil unit 10 of each cylinder, wasteful power consumption during standby can be eliminated.

(Example 2) (Fig. 5)
The difference between the internal combustion engine ignition device 100 of the second embodiment and the internal combustion engine ignition device 100 of the first embodiment (FIG. 4) is that the discharge control circuit 40 transmits the operating status of the internal combustion engine and is based on this operating status. The target value of the control target item is calculated to control the control target item.

That is, the discharge control circuit 40 is based on, for example, the engine rotation speed of the internal combustion engine calculated based on the discharge timing transmitted from the ignition coil unit 10 of each cylinder, or the intake negative pressure sensor provided in the internal combustion engine, the internal combustion engine. Obtaining the detection signal of the driving status detecting means 120 such as the accelerator sensor and the vehicle speed sensor of the mounted vehicle, the arithmetic circuit and data built in the CPU (the engine rotation speed and / or the detected values of various sensors) Presence / absence of auxiliary voltage EA for spark discharge, setting of auxiliary voltage EA for spark discharge, presence / absence of addition of auxiliary voltage EB for heat retention discharge, setting of auxiliary voltage EB for heat retention discharge, auxiliary voltage EB for heat retention discharge The control operation of (b) above is performed based on the map data or the like in which the number of times of addition of is predetermined.

Therefore, the internal combustion engine ignition device 100 according to the second embodiment also has the same effects as the above-mentioned (a) to (e) in the internal combustion engine ignition device 100 according to the first embodiment.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like within a range not deviating from the gist of the present invention. Included in the present invention. For example, the present invention can also be applied to an ignition device for a single-cylinder internal combustion engine.

According to the present invention, in the ignition device for an internal combustion engine, the ignition performance of the air-fuel mixture by the spark plug can be improved.

Further, according to the present invention, it is possible to reduce the consumption of the electrodes of the spark plug in the ignition device for an internal combustion engine.

10 Ignition coil unit 11 Current cutoff type ignition device 12 Ignition coil 14 Ignition plug 30 Trigger circuit 40 Discharge control circuit 41 Main output element 42 Output element 43 Output element 50 Spark discharge auxiliary circuit 60 Thermal insulation discharge auxiliary circuit 100 Ignition for internal combustion engine Device 110 External controller 120 Operating status detection means EA Auxiliary voltage for spark discharge EB (EB-1, EB-2 ...) Auxiliary voltage for heat retention discharge

Claims (4)

Using an ignition coil unit with a built-in current cutoff ignition device,
The current cutoff type ignition device cuts off the primary current of the ignition coil and generates a high voltage which is a large transmission power on the primary side of the ignition coil, so that a larger voltage is generated on the secondary side of the ignition coil. Due to the high voltage, a high-voltage spark discharge is generated between the electrodes of the spark plug to generate a flame nucleus between the electrodes, and a small-voltage heat-retaining discharge following the spark discharge is generated to grow the flame nucleus. It is an ignition device for an electric discharge engine.
It has an auxiliary capacitor for spark discharge, and the high-voltage capacitor voltage accumulated in the auxiliary capacitor for spark discharge is used as an auxiliary voltage for spark discharge and is applied to the primary side of the ignition coil in the ignition coil unit during spark discharge. Auxiliary circuit and
It has one or more auxiliary capacitors for heat retention and discharge, and the capacitor voltage accumulated in the auxiliary capacitors for heat retention and discharge is added to the primary side of the ignition coil in the ignition coil unit during heat retention and discharge as the auxiliary voltage for heat retention and discharge. Auxiliary circuit for heat retention and discharge
It is configured to have an auxiliary circuit for spark discharge and a discharge control circuit that controls the auxiliary circuit for heat retention discharge.
The discharge control circuit determines whether or not an auxiliary voltage for spark discharge is added, whether or not an auxiliary voltage for spark discharge is added, whether or not an auxiliary voltage for heat retention discharge is added, and whether or not an auxiliary voltage for heat retention discharge is added, depending on the operating conditions of the internal combustion engine. It is assumed that at least one of the control target items including the voltage setting and the number of times the auxiliary voltage for heat retention and discharge is applied can be controlled .
In addition
It has a trigger circuit that detects the high voltage generation timing by the current cutoff type ignition device of the ignition coil unit as the discharge timing.
Based on the discharge timing detected by the trigger circuit, the discharge control circuit outputs the output element of the auxiliary voltage for spark discharge by the auxiliary circuit for spark discharge and the output element of the auxiliary voltage for heat retention discharge by the auxiliary circuit for heat retention discharge. Ignition system for internal combustion engines. The ignition device for an internal combustion engine according to claim 1, wherein the discharge control circuit transmits a target value of the control target item from the outside and controls the control target item. The ignition device for an internal combustion engine according to claim 1, wherein the discharge control circuit transmits the operating status of the internal combustion engine, calculates a target value of the controlled target item based on the operating status, and controls the controlled target item. .. Any of claims 1 to 3 , wherein an ignition coil unit is provided in each of the plurality of cylinders, and each single spark discharge auxiliary circuit and a heat retention discharge auxiliary circuit shared by the ignition coil unit of each cylinder are provided. Ignition system for internal combustion engine described in.

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