WO1988001805A1

WO1988001805A1 - Switching circuit

Info

Publication number: WO1988001805A1
Application number: PCT/JP1987/000612
Authority: WO
Inventors: Toshiyasu Suzuki
Original assignee: Toshiyasu Suzuki
Priority date: 1986-08-25
Filing date: 1987-08-17
Publication date: 1988-03-10

Abstract

A switching circuit which can be easily turned off and forcibly maintained in that state, and which has a self-holding function and a self-arc-extinguishing function. For instance, when it is detected by voltage detecting means (comparator 3) that a voltage across the base and the emitter of a bipolar transistor (7) is greater than a predetermined value, switching means (transistor 6) operated (via a transistor 5) according to the voltage detecting means connects the collector and the base of said bipolar transistor (7) together.

Description

W /

1

Light

Nomenclature of the invention Switching circuit technology-This invention makes it easy to turn off or forcefully keep it off so that it does not turn on due to malfunction. The present invention relates to a switching circuit having a self-holding function and a self-extinguishing function. ,

Therefore, the present invention provides a G T〇 (gate-turn-off thyristor).

Instead of a power conversion circuit using a resonance circuit (: a series inverter> or a device that applies this power conversion circuit, if it is clean, an ignition device including an internal combustion engine ignition device, a high voltage generator, It is used in ozonizers, discharge lamp lighting devices, induction ripening devices, etc. Background technology Conventionally, there is a GTO as a switching means having a self-holding function and a self-extinguishing function. The enlarged one is the switching method shown in Fig. 2. (Reference: Japanese Patent Publication No. 55-37178) However, in order to turn off the GTO, it is necessary to provide a means for flowing a current of a fraction of the magnitude of the anode current from the power source to the gate. Moreover, when an overcurrent flows through the GTO, such as in a power short-circuit state or an overload state, it is difficult to turn off the GTO.

In addition, to force this off so that it does not turn on due to a malfunction, either short-circuit the gate and the force sword, or keep the gate potential lower than the force sword potential. It is necessary to provide a means. For this reason, there is a disadvantage in that the switching means and the means for turning GTO off and forcibly keeping it off in FIG. 2 are complicated and costly.

In addition, immediately after forcibly turning off the GTO, considering that the GTO that had been turned on due to malfunction should be turned off, whenever the GTO must be turned off, It is the best to keep the off-current flowing through the gate-force sword orchard, but the energy consumption increases. In addition, as shown in Fig. 3, an equivalent circuit of a well-known thyristor that combines a PNP transistor 1 and an NPN transistor 2 can be considered. In this case, since the collector current of one of the transistors 1 and 2 becomes the base current of the other, the base current of the transistors 1 and 2 increases as the main current of the switching means increases. Is also large. Therefore, the maximum current that can flow through these collectors! Is limited by the maximum rated value of these base currents, and the maximum value of the main current is smaller than the maximum value of the main current of transistor 1 or 2 used alone in normal use. It is in the switching means.

Further, this switching means also has a disadvantage that it is difficult to turn on / off the transistor 1 or 2 when an overcurrent flows, such as in a power supply short-circuit state or an overload state.

Incidentally, one measure of the maximum value that the base current of the transistors 1 and 2 can reach is the value of both base currents when the product of the emitter DC current gains of the transistors 1 and 2 becomes 1.

Furthermore, when switching means with a high withstand voltage and a large current capacity is required, there is also a problem that there is hardly any PNP transistor 1 satisfying these conditions.

In order to solve this problem, as shown in Fig. 4, the current rating of transistors 1 and 2 is reduced and the transistors are easily turned on and off while expanding the main current capacity like the GTO described above. Fig. 5 shows the switching means. (Reference: Japan Patent Publication No. 56-509, No. 56-262 16)

However, they have the disadvantage that it is not yet easy enough to turn transistors 1 and 2 off and forcibly keep them off. This will be explained with reference to the arm pair in FIG. This arm pair consists of two switches connected in series as shown in Fig. 5. The signal is input from input terminals tl and t2. Two rectifiers 4 7 form opposite arm pairs

Both switches are controlled so that when one is on, the other does not turn on. The purpose is to prevent them from shorting the DC power supply 41 due to malfunction.

To this end, the base current of the transistor 51 passes from the DC power supply 41 through the switching means, the diode 48 and the resistor 50 during the ON period of the switching means which is located at the top of the figure. On the other hand, during the ON period of the switching means on the lower side of the figure, the base current of the transistor 43 passes through the resistor 46, the diode 48, the switching means, and the DC power supply 41.

However, the magnitude of each current must be smaller than the respective holding current so that the current flowing through each diode 48 does not prevent the switching means from turning off.

Two sets of diodes 48 and rectifiers 49 prevent these currents and the main current of this arm pair from interfering with each other. Diode 48 and rectifier 49 should preferably be of the fast-recovery type. The two diodes 42 protect the emitter junctions of the transistors 43-45, 51, 52 from reverse surge voltages.

With such a configuration, when the upper switching means is on, the transistors 51 and 52 turn off the lower switching means, and when the lower switching means is on. The transistors 43 to 45 keep the switch off of the switch of However, for that purpose, the transistors 43 to 45 or 51, 52 must not lose as much as the base current of the transistors 1, 2 can reach. Turn 2 must be able to turn off.

This is because the transistors 1 and 2 can be forcibly kept off, which means that two sets of transistors 1, 2, 39 and 40 are likely to turn on simultaneously due to a malfunction caused by noise or the like. This means that even if an overcurrent flows through the bases of transistors 1 and 2, transistor 1 or 2 can be turned off.

Therefore, since it is necessary to amplify the current of each minute diode 48 in two or three steps (in some cases, more) as in this example, the means for keeping these off is complicated. . In other words, turning off transistors 1 and 2 is still not easy enough

One way to solve this is to use transistors with low current rating in transistors 1 and 2 in order to reduce the amount of base current that can reach transistors 1 and 2 in the switching means shown in FIG. The use of a smaller transistor increases the number of transistors connected in Darlington and amplifies it. However, increasing this has the disadvantage of increasing its on-state voltage.

As described above, in each of the switching means shown in FIGS. 4 and 5, it is not possible to turn off or forcibly keep them turned off. The disadvantage that these switching means are not yet easy enough is that the switching means shown in Figs. 4 and 5 are limited to bipolar transistors in their entirety. There is also a disadvantage. For example, it would be useful if a switching means with a low on-voltage, a self-holding function and a self-extinguishing function could be constructed using a BIM〇S composite device in which a power MOSFET and a bipolar transistor were cascaded. That is. Therefore, the present invention makes it easy to turn off or forcibly keep the switch off so that it does not turn on due to a malfunction. Alternatively, an on-voltage lower than these can be maintained, and, except for a part thereof, switching means other than a bipolar transistor can be used. A switch having a self-holding function and a self-extinguishing function can be used. DISCLOSURE OF THE INVENTION That is, the present invention relates to a circuit for detecting a voltage of a base-emitter of a bipolar transistor Q1 that is larger than a predetermined value. The switching means that operates in accordance with the voltage detection means is a bipolar / switching circuit that connects the collector and base of the transistor Q1. You.

(However, the bipolar transistor Q1 may be a Darlington-connected multiple bipolar transistor.)

Thus, when the if switching means is on, it connects the collector to the base, so that part or all of the main current of the switching circuit flows to the base. As long as this main current is larger than the set value of the holding current of the switching circuit (this corresponds to the holding current of the thyristor, hereinafter, it will be referred to as), the voltage between the base and the emitter is maintained. The voltage is almost constant. Otherwise, this voltage will be less than that constant voltage, approaching zero cU.

Therefore, as long as the voltage detecting means detects that the base-emitter voltage is larger than the voltage set value corresponding to the set value of the holding current, the voltage detecting means keeps the switching means on. If not, the voltage detection means! ί Keep the switching means off.

Therefore, the entire operation of the present invention is positive feedback. If this positive feedback operation is prevented, the present invention can be easily turned off. Therefore, the present invention has a self-holding function and a self-extinguishing function.

Further, the base and the emitter of the bipolar transistor Q1 convert the current into a voltage, and the voltage is detected by the voltage detecting means, so that the magnitude of the main current and the set value of the holding current are determined. I understand the big and small warriors. As a result, there is no need to insert a new current detecting means in the main current path in order to detect the magnitude of the main current, so that the on-voltage can be reduced. There is in the invention. Further, if the main current of the present invention is larger than the setting current of the holding current, the base-emitter voltage is almost constant regardless of the magnitude. Moreover, at this time, since the voltage detecting means operates according to the constant voltage, the operation is the same regardless of the magnitude of the main current. Therefore, even if the main current is large, the present invention is not particularly liable to be turned on and off, so that the turn-off is as easy as when the main current is small. This has the effect of the present invention.

Then, since the switching means may be turned on and off in accordance with the voltage detection means, it may not be a bipolar transistor. Therefore, the present invention has an advantage that the switching means other than the bipolar transistor can be used as the switching means, which is more convenient than the prior art. In the case where the present invention is the switching circuit according to claim 3, the constant voltage means described in the same claim, the voltage detection means described in the same claim is the base-emitter of the bipolar transistor Q1 described in the same claim. Help detect the voltage between. Therefore, the present invention has an advantage that this voltage detecting means can be simply constituted by a transistor or the like. In the case where the present invention is applied to the switching circuit of claim 9, this advantage is obtained. In addition, the bipolar transistor Q2 described in the above section expands the main current capacity of the bipolar transistor Q1 described in the above section, so that the main current capacity of the present invention is increased. There is in the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1, FIG. 6 to FIG. 15 are circuit diagrams of each embodiment of the present invention. 2 to 5 are circuit diagrams of conventional switching means.

FIG. 16 is a circuit diagram of an arm pair using a conventional switching means. FIG. 17 is a circuit diagram of an arm pair using an embodiment of the present invention.

FIG. 18 is a circuit diagram showing an embodiment of the present invention and a circuit of an ignition device using the same.

FIG. 19 is a circuit diagram showing two embodiments of the present invention and a circuit of an ignition device using the two embodiments. '

FIG. 20 is a circuit diagram showing a circuit of a bridge-type series inverter using the embodiment of the present invention.

FIGS. 21 (a) and 21 (b) are circuit diagrams showing a circuit of a prism type series inverter using an embodiment of the present invention.

FIG. 22 and FIG. 23 are circuit diagrams each showing a circuit of an ignition device using the embodiment of the present invention.

FIG. 24 and FIG. 25 are circuit diagrams of the circuit of the ignition device with the electronic distribution function using the kiyoshi according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

In the implementation of FIG. 1, the transistor 7 corresponds to the above-mentioned bipolar transistor Q1, the comparator 3 corresponds to the above-described voltage detecting means, and the transistor 6 corresponds to the above-mentioned switching means.

The magnitude V st of the reference voltage is set between the voltage terminal and the base-emitter voltage of the transistor 7 when the transistor 7 is turned on with reference to the emitter potential of the transistor 7.

When the main current of the switching circuit is small when the transistor 6 is on, most of the main current flows through the base of the transistor 7 and the resistor 8. However, if this main current is large, only part of it will flow through the base and the resistor 8, most of which will flow into the collector of the transistor 7.

Therefore, regardless of the magnitude of the main current, the base-emitter voltage of the transistor 7 becomes substantially constant. However, when the main current becomes a value close to zero, this voltage also approaches zero, so that it is possible to know from the magnitude of this voltage whether the main current is larger than a predetermined value.

Thus, if the main current is greater than the predetermined value, the transistor 6 operating according to the comparator 3 via the transistor 5 connects the collector and base of the transistor 7; otherwise, the comparator 3 is connected via the transistor 5 Turn off transistors 6 and 7.

Here, the role of the resistor 8 is important. Its role is to stabilize the voltage between the base and the emitter of the transistor 7 and detect the voltage of the comparator 3 In addition to helping to increase the turn-off speed of the transistor 7, it is useful in setting the magnitude of the holding current in this embodiment.

Even if the product of the magnitude of the holding current and the magnitude of the resistor 8 is smaller than the voltage between the base and the emitter when the transistor 7 is turned on, the transistors 5 and 6 are turned on, Since it is possible to turn on the power supply, there is no problem in setting the magnitude of this holding current.

Rather, the magnitude of the holding current and the resulting voltage drop of the resistor 8, that is, the voltage between the base and the emitter of the transistor 7, become clear. The resistor 8 has the effect that not only the setting becomes accurate, but also the range of setting values that can be selected is expanded.

By the way, in order to turn off this implementation ^ or to forcibly keep it off, short-circuit the positive input terminal of comparator 3 to the emitter of transistor 7 or temporarily apply the reference voltage Vst. Or the transistor 5 base and the emitter may be short-circuited.

Since the base current of the transistor 5 does not become larger than a certain small value regardless of the magnitude of the main current in this embodiment, it is relatively easy to short-circuit the base and the emitter of the transistor 5. The ON voltage in this embodiment is the sum of the voltage between the emitter and the collector of the transistor 6 and the voltage between the base and the emitter of the transistor 7, and this is referred to as the switching means in FIG. The same as the ON voltage of Can be. In the embodiment of FIG. 6, the transistor 11 is the same as the switching transistor Q1 of the first embodiment, the transistor 10 is the same as the switching means of the first embodiment, and the transistor 9 is the same as the switching means of the first embodiment. These correspond to the voltage detection means described in item (1). This embodiment corresponds to the switching circuit of claim 6.

A column circuit of rectifiers 12 and resistors 16 helps transistors 9 etc. detect the base-emitter voltage of transistor 11.

In other words, if the set value of the base-emitter voltage of the transistor 11 is smaller than or equal to that of the transistor 9 or the base-emitter voltage of the transistor 9 at the time of 'turn-on', the transistor 9 etc. 1 Base-emitter voltage cannot be detected.

Therefore, the present inventor added the voltage of the parallel circuit to the base-emitter voltage of the transistor 11 so that the transistor 9 and the like can detect the base-emitter voltage. There is no problem in voltage detection. This is because there is a one-to-one correspondence between the voltage across the base of the transistor 11 and the voltage between the base of the transistor 11 and the cathode of the rectifier 12.

By the way, the holding current value of this embodiment is the value of the resistances 13 to 16 and the base emitter of the transistor 9 when the transistor 9 is turned on.

Then, the ON voltage of this embodiment is determined by the emitter of the transistor 10. -The collector-to-collector voltage and the transistor-to-base emitter voltage

, Rectification 1 2 electricity] Ϊ. On the other hand, the ON voltage of the switching means in FIG. 4 is the sum of both the voltage between the base and the emitter of the transistors 2 and 39 and the voltage between the emitter and the collector of the transistor i.

Therefore, there is an advantage in this embodiment that the on-voltage of this embodiment can be reduced to about the on-voltage of the switching means in FIG.

In addition, during the ON period of this embodiment, the sum of the voltages of the resistors 15 and 16 stabilizes before and after the double voltage, so that the base current of the transistor 9 becomes a small current having an upper limit, and the transistor 9 is turned on. · It is easy to turn off. Therefore, this embodiment can be easily turned off. Of course, even if the transistor 10 is used, the turn-off can be performed.

The resistor 16 may be omitted, but if it is provided, the set value of the holding current can be made accurate. In the embodiment of FIG. 7, the parallel circuit of the resistor 17 and the rectifier 18 is connected to the base side of the transistor 11, and the role is the role of the resistor 16 and the rectifier 12 in FIG. Is the same as Thus, the current rating of rectifier 18 may be lower than that of rectifier l 12. This implementation corresponds to the switching circuit of the eighth aspect of the present invention.

The resistor 17 may be omitted, but if it is present, the set value of the holding current can be made accurate.

Transistors 10 and 11 are connected in Darlington via fir parallel circuit Since the transistor ι オン is turned on, it connects the collector and the base of the transistor 11 through this column circuit.

The operation and effect of this embodiment are almost the same as those of FIG. The embodiment of FIG. 8 is similar to the embodiment of FIG. The latter transistor 9 has a common emitter, while the former has a common base. For this reason, the former saved one resistor compared to the latter.

During the ON period of this implementation, the sum of the voltages of the resistors t 5 and 16 is almost constant, so the collector current of the transistor 9 is also almost constant, and the magnitude is determined by the constant voltage and the value of the resistor 19. . That is, in this embodiment, a constant current path in which a constant current flows through the collector of the transistor 9 is formed.

The operation is as follows. This increase in the collector current leads to an increase in the voltage of the resistor 19, an increase in the emitter potential of the transistor 9, and a decrease in the base current. Conversely, this decrease in collector current leads to an increase in base current. Thus, its collector current is kept constant

Thus, the reading of transistors 9 and 10 is similar to that of transistors 1 and 2 in FIG. 3, but the operation of both is different.

The ON voltage of this embodiment can be the same as that of the embodiment of FIG. 6, and the same as that of the switching means of FIG. Further, if the base of the transistor 9 and the mixer are short-circuited, this embodiment can be easily turned off. In the embodiment shown in FIG. 9, the parallel circuit of the resistor 17 and the rectifier 18 is connected to the base {¾ of the transistor 11, but its role is the same as that of the resistor 16 and the rectifier 12 in FIG. Same as role.

Since the transistors 10 and 11 are Darlington connected through this column circuit, when turned on, the transistor 10 connects the base and the collector of the transistor 11 through this parallel circuit.

The operation and effect of this embodiment are almost the same as those of the embodiment of FIG. In the embodiment of FIG. 10, the transistors 22 and 23 connected in a Darlington connection are the bipolar transistor Q1 described in claim 1, and the transistor 21 is the switching transistor described in claim 1. It can be considered that the transistor 20 and the like correspond to the voltage detecting means described in the above item.

Or, except for the transistor 23, the corresponding relationship is as described above. The transistor 23 expands the main current of the transistor 22 and the transistor 20 etc. is the base of the transistor 22. It can also be considered that the base-emitter voltage of the transistor 23 helps to detect the inter-electrode voltage.

In any case, if the magnitude of the main current of this embodiment is equal to or larger than the set value of the holding current, the voltage between the base of the transistor 22 and the emitter of the transistor 23 is at a substantially constant predetermined value. This voltage is Keep the transistors 20 and 21 on and the transistors 22 and 23 turn on as their main currents increase.

Incidentally, the holding current of this embodiment is determined by the voltage between the base and the emitter of the transistor 20 when the transistor 20 is turned on and the value of the resistors 24 to 27.

Then, the ON voltage of this embodiment is the sum of the base-emitter voltage of both the transistors 22 and 23 and the emitter-collector voltage of the transistor 21. On the other hand, the ON voltage of the switching means in FIG. 4 is the sum of the base-emitter voltage of both transistors 2 and 39 and the emitter-collector 閎 voltage of transistor 1.

Therefore, this embodiment has the advantage that the on-voltage of this embodiment can be made the same as the on-voltage of the switching means in FIG.

In addition, during the ON period of this embodiment, the sum of the voltages of the resistors 26 and 27 stabilizes around 2 volts, so that the base current of the transistor 20 becomes a small current having an upper limit and the transistor 20 It is easy to turn off. Of course, since the base current of the transistor 21 is also smaller, it is easy to turn it off.

Therefore, the effect of this implementation is that the implementation can be easily turned off or forcibly maintained. The embodiment of FIG. 11 is similar to the embodiment of FIG. The latter transistor 20 has a common emitter, while the former has a common base. For this reason, the person saved one resistor compared to the latter. During the ON period of this implementation, since the voltage phases of the resistors 26 and 27 are almost constant, the collector current of the transistor 20 is also almost constant, and the magnitude is determined by the constant voltage and the value of the resistor 28. Decided.

That is, similarly to the embodiment shown in FIGS. 8 and 9, also in this embodiment, a constant current circuit in which a constant current flows through the collector of the transistor 20 is formed.

Thus, even though the connections of transistors 20 and 21 are similar to those of the switching scheme of FIG. 3, their operations are different.

The operation and effect of this embodiment are almost the same as those of the embodiment of FIG.

'Comparing the switching means shown in FIGS. 10 and 11 with the switching means shown in FIG. 5, these embodiments have one or two more resistors in terms of the number of parts, but the ON voltage is higher. These embodiments have the effect that the pressure can be reduced by about 1 volt, and the forced turn-off and the maintenance of the forced off are easy. The present inventors will specifically describe this in the description of FIG. 17 described later. Fig. 12 and Fig. 13 are also possible. These are more advantageous in terms of on-voltage and off than the switching means of FIG. 5 in which the number of Darlington-connected transistors is increased by one stone. Note that each implementation of FIGS. 10 ϋ to 13 is defined in claim 9 or 10. This corresponds to the switching circuit of the term tT 载. In the embodiment shown in FIG. 14, the transistor 32 is the same as the bipolar transistor Q1 described in claim 1, the transistor 31 is the switching means described in the above item 1, the transistor 29 is the same as the transistor. These correspond to the voltage detection means described above.

Transistor 29 controls transistor 31 via transistor 30. Rectifiers 33 help detect the voltage of transistor 29 etc. In the embodiment shown in FIG. 15, the transistor 38 is the same as the bipolar transistor Q1 of the first embodiment, the field-effect transistor 37 is the switching means of the first embodiment, and the comparator 3 is the same as the switching device of the first embodiment. These correspond to the voltage detection means described in section-.

The transistors 34 to 36 drive the transistor 37 according to the comparator 3. The reference voltage V st is based on the emitter potential of the transistor 38.

It is easy to turn this implementation off. This can be done by short-circuiting the negative input terminal of comparator 3 and the emitter of transistor 38, temporarily increasing the reference voltage V st, shorting the base and emitter of transistor 34, etc. , do it.

If a power MOS FET having a low on-resistance is used for the transistor 37, the on-voltage of this embodiment can be reduced. From here, the present inventors will specifically describe the method of using the present invention. The circuit of FIG. 1.7 is an arm pair using two embodiments of FIG. 1.1. Each trigger signal is input from input terminal t3, input terminals t4 and t5.

Both switching circuits are controlled so that when one of them is on, the other does not turn on, so that they are prevented from shorting the DC power supply 41. -Its basic operation is the same as that of the circuit of Fig. 16 described above. When the upper switching circuit of FIG. 17 is on, transistor 54 keeps the lower switching circuit of FIG. 17 off, while when the lower switching circuit is on, Transistor 53 keeps its upper switching circuit off.

It is clear that the means of keeping off in the circuit of FIG. 17 is simpler than that of the circuit of FIG. This is because the switching circuit of FIG. 11 is easier to turn off and forcibly keep off than the switching means of FIG. The circuit of FIG. 18 is a circuit of a series inverter type ignition device using another embodiment and a thyristor 60. In the figure, 55 is a three-terminal regulator, 56 is a DC-DC converter that outputs a negative voltage, 67 is a firing coil, and 68 is a discharge gap for ignition.

This implementation is a switching composed of transistors 61 to 65, etc. Circuit. The transistor 63 corresponds to the switching means described in claim 1, and the transistor 64 corresponds to the voltage detecting means described in claim 1.

Further, it may be considered that the transistors 61 and 62 correspond to the bipolar transistor Q1 described in the above item [2]. Alternatively, only the transistor 62 corresponds to the transistor, the transistor 61 increases the main current of the transistor 62, and the transistors 64 and the like detect the voltage between the base and the emitter of the transistor 62. You may think that the base emitter voltage of 1 helps.

When this switching circuit is on, transistor 64 keeps transistor 63 on via transistor 65.

The on-voltage of this switching circuit is the sum of the base-emitter voltage of both transistors 616 and the emitter-collector voltage of transistor 63. Therefore, this embodiment has an effect that this voltage can be reduced to about the ON voltage of the switching means shown in FIG.

Also, to turn the switching circuit off and on or to force it off, use one of the transistors 63-65. Therefore, this switching circuit has the effect that the forced turn-off and the forced off hold are easy. The main circuit is based on a DC power supply formed by a DC-DC converter 56 and a power supply capacitor 57, a switching circuit of the present invention, and a thyristor. W 8/1

twenty one

This is a series inverter composed of a capacitor 60, a commutation capacitor 71, and a primary coil 67a.

Since the two diodes 103 are provided to prevent surge voltage, almost no current flows through them.

Rectifiers 69, 70 limit the voltage on commutation capacitor 71 from zero voltage to the voltage on power supply capacitor 57. These actions are as follows. During the life of the thyristor 60, the thyristor 60 and the rectifiers 70 and 49 serve as a flywheel diode for the primary coil 67a. On the other hand, during the ON period of the switching circuit of the present invention, the switching circuit and the rectifiers 49 and 69 play the role.

Then, the control method of this series inverter: ignition system is different from the conventional one. In this igniter, when one of the switching circuits and the thyristor 60 is turned off and the other is turned off so that the timing when the thyristor 60 turns on and off is automatically optimized, this turning off turns off the other. One turns on automatically.

That is, one turn-off triggers the other turn'on.

(Therefore, hereafter, such a control method will be referred to as a turn-off.trigger method. Reference: Japanese Patent No. 625019)

For this purpose, the transistors 58 and the like detect the on / off of the switches of the present invention, and the transistors 66 and the like detect the on / off of the thyristor 60. These on / off detections The circuit configuration of this is basically the same as that of the circuit of Fig. 16 and Fig. 17. Of course, each diode 4 One

The magnitude of each current is set smaller than each holding current value so that the current flowing through 8 does not prevent the switching circuit and the thyristor 60 from turning on and off.

Here, the trigger of the thyristor 60 will be described. The usage of the pulse-transformer 74 is different from the usual one, in which the saturation of the magnetic flux is positively used.

When the transistor 59 is turned on, the voltage induced on the secondary side of the pulse transformer 74 is applied to the gate of the thyristor 60, but the magnetic flux of the pulse transformer 74 saturates immediately. However, this voltage also quickly decreases, and the trigger of the six thyristors ends in a very short time.

This minute time does not affect the time of the thyristor 60, which is determined by the current of the primary coil 67a, and the trigger power of the thyristor 60. The present inventor has set the value of the resistor 75 and the characteristics of the pulse transformer 74 so that the above is sufficient.

Naturally, the exciting inductance of the pulse transformer 74 is smaller than usual.

When the transistor 59 turns off, the magnetic energy of the pulse-transformer 74 is dissipated by the resistor 73 and the antenna diode 72, and the next trigger of the thyristor 60 is prepared.

Next, the trigger of the switching circuit of the present invention will be described. When the transistor 66 is turned on together with the thyristor 60, current flows from this collector to the ground through the resistor 76 and the diode 78.

The base potential of transistor 63 is set to 0.6 volts. The turn-on of the transistor 63 is prevented, and the capacitor 77 is also charged at the same time, and the trigger of the switching circuit is prepared.

When transistor 66 turns on together with thyristor 60, capacitor 77 discharges through resistor 79, the emitter, transistor, base, etc. of transistor 63, so that this switching circuit turns. Turn on.

The overall operation of the ignition device is as follows. When the ignition signal input to the input terminal t 6 rises, if the switching circuit and the transistor 58 of the present invention are off, the transistor 59 turns on and the pulse transistor 74 turns off. Trigger thyristor 60.

When the thyristor 60 is turned on, since the voltage of the commutation capacitor 71 is zero, the voltage of the power supply capacitor 57 is directly applied to the primary coil 67a. As a result, a high voltage is induced in the secondary coil 67b, and a spark is generated in the ignition discharge gap 68.

Thereafter, when the primary reverse current becomes zero and the thyristor 60 is turned off, the transistor 66 is also turned off at the same time, so that the capacitor 77 triggers the switching circuit of the present invention.

When this switching circuit is turned on, the voltage of the commutation capacitor 71 charged to the voltage of the power supply capacitor 57 is applied to the primary coil 67 a in the opposite direction to the above. As a result, a high voltage in the opposite direction is induced in the secondary coil 67b, and sparks are generated in the ignition discharge gear 68.

During the ON period of this switching circuit, transistors 58 When the star 59 is turned off, the magnetic energy of the pulse 'transformer 74 is released and the next trigger of the thyristor 60 is prepared.

When transistor 58 turns on and off with the switching circuit of the present invention, transistor 59 turns on if the ignition signal is high-level. The same is repeated hereinafter. This repetition continues as long as the ignition signal is at a high level.

However, at the time of the turn-off, if the ignition signal is at a low level, the transistor 59 remains off and the ignition device stops generating a spark. The ignition device of the series inverter type generates a spark when charging and discharging the commutation capacitor 71. On the other hand, the well-known CDI (capacitor discharge ignition) igniter generates a spark only when the capacitor is discharged.

Therefore, hereinafter, the former ignition method will be referred to as a capacitor charge / discharge ignition method, or simply C CDT (Cond se nse r Char gea n d Diis ccha rge [gni tίon)), and the double CD [method]. The circuit in FIG. 19 is also a circuit of a CCDI ignition system. The control method is the turn-off-trigger method described above.

This circuit is a circuit using another embodiment of the present invention instead of the thyristor 60 in FIG. 18. The implementation is performed by transistors 81 to 85 and the like. Composed

Transistors 81 and the like detect the voltage between the base of transistor 84 and the emitter of transistor 85. Transistor 81 controls transistor 83 via transistor 82.

When the switching circuit composed of the transistors 61 to 65 and the like is on, the transistor 58 keeps not only the transistor 59 but also the transistors 83 to 85 off. Therefore, the two kinds of switching circuits of the present invention are completely prevented from short-circuiting the DC-DC converter 56 and the power supply capacitor 57.

When the transistor 59 is turned on, the charging current of the capacitor 80 flows to the emitter and base of the transistor 82, so that the switching circuit composed of the transistors 81 to 85, etc. triggers. Is done. Conversely, when transistor 59 turns off, capacitor 80 discharges, preparing the next trigger for this switching circuit.

The operation of the entire igniter is the same as that of the igniter of FIG. A switching circuit composed of transistors 61 to 65 and the like can be replaced with that shown in FIG. 10 or FIG.

In addition, the ignition device shown in FIGS. 18 and 19 becomes a high voltage generator that generates an alas and a negative high voltage if the ignition discharge gear 68 is *, and the ignition discharge gap 68 If you read in the discharge lamp instead of, the discharge lamp lighting device will be g. In addition, these can be read as ozone generating discharge gears instead of ignition discharge gaps 68 to become intelligent zonizers, and instead of primary coils 67 a, inductive maturation coils can be connected. , Induction Become a mature device

Incidentally, when sparks are generated by increasing the gear length of the ignition discharge gear 68, generation of ozone is recognized. The circuit shown in FIG. 20 is a bridge-type series inverter having a function of preventing a short circuit of the DC power supply 41 and using four switching circuits shown in FIG. Each switching circuit is formed by transistors 20 to 23 and the like.

This main circuit is composed of a DC power supply 41, these four switching circuits, four rectifiers 47, a commutation reactor 86, a commutation capacitor 87, and a load resistance 88. The control method is the turn-off-trigger method described above.

When the inverter starts, when the start-stop signal input to the input terminal t8 falls, the transistor 100 is turned on. Then, the charging current of the capacitor 101 flows to the base and the emitter of the transistor 102, so that the transistor 1 and 2 trigger the switching circuit at the upper right of the figure. .

When this switching west is on, transistor 98 keeps the lower right switching circuit off, while transistor 93 keeps the lower left switching circuit on. Therefore, at this time, the transistor 95 keeps the switching circuit in the upper left of the drawing off, and the transistor 92 charges the capacitor 91.

That is, as long as the upper right switching circuit is on, transistor 93 keeps its lower left switching circuit on, so that the transistor /

2 7

The star 92 can detect both ON and OFF from the ON / OFF detection of the lower left switching circuit.

When the upper right and lower left switching circuits are turned, the discharge current of the capacitor 91 flows to the base and the emitter of the transistor 90, so that the transistors 90 and 89 are switched to the left 1: Trigger the circuit.

When its upper left switching circuit is on, transistor 94 keeps its lower left switching circuit off, while transistor 97 keeps its lower right switching circuit on.

Therefore, at this time, the transistor 96 keeps the upper right switching circuit off, and the transistor 99 keeps the transistor 100 off to discharge the capacitor 101.

In other words, as long as the upper left switching circuit is on, the transistor 97 keeps the lower right switching circuit on, so that the transistor 99 can turn on the lower right switching circuit. From the detection, both on and off can be detected.

When the transistor 990 turns off together with its upper left and lower right switching circuits, if the start / stop signal is low, the transistor 100 turns on, and so on. Repeated . This repetition continues as long as the start / stop signal is at the σ- · level. However, at the time of turn-off, if the start / stop signal is high-level, the transistor 100 remains active and the operation of the inverter stops. The circuits shown in Fig. 21 (a) and (b>) are the -circuits of a bridge-type series inverter using four 11I switching circuits that have the function of preventing short-circuiting of the DC power supply 41. The same reference numerals are attached to the surrounding terminals ctl to ct 8, respectively.

These switching circuits are switching circuits 107 to 110, and the circuit configuration for preventing short-circuiting of the DC power supply 41 utilizes that of the arm pair shown in FIG.

The control method for this event is the turn-off trigger method described above. For this purpose, the transistors 92, 104, etc., switch on and off the switching circuits 1, 8, 109, and the transistors 99, 105, etc. detect the on / off of the switching circuits 107, 110. Then, when the start / stop signal input to the input terminal t9 falls, or while this signal is at a low level, the switching circuit is activated and neither 07 nor 110 is turned on. L10, etc. trigger the switching circuits 108, 109 when the switch is turned on.

Conversely, when both switching circuits 108, 109 are no longer on, transistors 89, 90, 132, etc. trigger switching circuits 107, 110. The 221st circuit is the circuit of the CCDI type ignition device described above, and its control method is the turn-off-trigger method described above. In addition, it plays the role of a flywheel diode against the primary coil 67a. The means to do this is in this circuit.

However, in the circuit of FIG. 180, one end of the commutation capacitor 71 is grounded, but in the circuit of FIG. 22, the one end of the primary coil 67a is grounded. It gets complicated.

When the switching circuit 112 is on, the rectifier 70 and the switching circuit 113 act on the primary coil 67a like a flywheel diode. Therefore, as long as the switching circuit 112 is on, the transistors 114 and the like continue to trigger the switching circuit 113.

On the other hand, when the switching circuit 111 is on, the switching circuit 111 and the rectifiers 49, 69 act on the primary coil 67a like a flywheel-diode.

Then, in order to prevent short circuit of DC power supply 141 or commutation capacitor 71, when switching circuit 112 or 113 is on, transistor 66 turns off switching circuit 111. To keep. Then, when the Sui Tsu quenching circuit 1 1 1 is on, the transistor 9 4 kept off the sweep rate Tsuchingu circuits 1 1 2, transistor 5 8 keep off the sweep rate Tsuchingu circuit 1 1 3 _v

Since the switching circuit 113 is turned on in conjunction with the switching circuit 112, the transistors 66 and the like are turned on and off by detecting the on / off of the switching circuit 113. 1 1 3 Both ON and OFF can be detected.

The entire trigger operation is the same as that of the circuit of FIG. The circuit of FIG. 23 is also the circuit of the above-described CCDI-type ignition device, and its control method is the turn-off-trigger method described in m. In addition, there is a means in this circuit to act as a flywheel-diode for the primary coil 67a.

In this circuit, unlike the circuit shown in Fig. 22, when the switching circuit 1 11 is on, the switching circuit 1 15 (the part surrounded by the dotted line) and the rectifier 69 are connected to the primary coil 67a. Acts like a flywheel or diode. Therefore, as long as the switching circuit 111 is on, the transistor 116 keeps triggering the switching circuit 115.

In addition, the transistors 58 and 94 can detect on / off of both the switching circuits 111 and 115 from the on / off detection of the switching circuit 115.

Further, after the transistors 66 and 117 keep the switching circuits 111 and 115 off when the switching circuits 112 and 113 are on, the circuit is the same as the circuit of FIG. Circuit of Figure 24, the two pairs of ignition coil 67 with ignition甩放electrostatic Giyappu 6 8 and, with the electron distribution function, the _ώ the main circuit is a round Mainai ignition instrumentation g of the aforementioned CCD I type 18 The main circuit shown is used. Switching switch 122 sets the spark at either ignition discharge gap 68. W 88/01805

3 1

—The problem occurs.

The switching circuit 118 charges the commutation capacitor 71 via the primary coil 67a, and the switching circuit 119 charges the commutation capacitor 121 via the primary coil 67a. Then, the switching circuit 120 discharges the commutation capacitor 71 or 121 via one of the primary coils 67a.

When switching circuit 120 is on, transistor 99 keeps switching circuits 118, 11 off through transistors 128, 95, 96. At the same time, transistor 99 keeps transistor 100 off and discharges capacitor 101.

On the other hand, when the switching circuit 118 or 119 is on, the transistor 123 causes the transistor 124 to keep the switching circuit 120 active and simultaneously charges the capacitor 125. When both switching circuits 118 and 119 are turned off, transistors 126 and 127 trigger switching circuit 120 according to the discharge current of capacitor 125. The circuit shown in FIG. 25 is also a circuit of the above-mentioned CCD I-type ignition device having two sets of ignition coil 67, ignition discharge gear 68, and electronic power distribution function. This main circuit uses the main circuit of FIG. Spark occurs in either ignition discharge gear 68 due to switching switch 122

The main circuit is as follows. >> The switching circuit 1 1 2 is the primary The charging capacitor 71 is charged through the coil 67a, and the switching circuit 130 charges the commutation capacitor 121 through the primary coil 67a. Then, the switching circuit 111 discharges the commutation capacitor 71 or 121 via one of the primary coils 67a.

Further, when the switching circuit 112 or 130 is on, the switching circuit 113 and the rectifier 70 or 131 act on each primary coil 67a like a flywheel diode. I do. To that end, the transistor 114 continues to trigger the switching circuit 113 as long as the switching circuit 112 or 130 is on. Japanese Patent No. 62-5019

P C T / J P 87X00053

Japanese Patent Application No. 62-086800

1987 No. 1-20234 Industrial applicability As described above, the switching circuit according to the present invention was turned off or forcibly kept off so as not to turn on or off due to malfunction. This is useful as a switching means having a self-holding function and a self-extinguishing function. Therefore, the present invention is useful not only as a substitute for GTO but also as a switching means that can be used in a power conversion circuit or the like in a new way.

Claims

Sought by ffl

(1) When the voltage detecting means detects that the base emitter voltage of the bipolar transistor Q1 is larger than a predetermined value, the switching means which operates in accordance with the voltage detecting means is provided with the bipolar transistor. A switch circuit that connects the collector and base of Q1. ·

(2) The switching circuit according to claim 1, wherein the switching means and the bipolar transistor Q1 are cascaded. .

(3) A constant voltage means for performing a constant voltage action on the current in the same direction as the forward direction is connected in series to the emitter junction of the bipolar transistor Q1, and the voltage of the series circuit is detected by the voltage detection means. 3. The switching circuit according to claim 1, wherein the switching circuit performs the switching.

(4) The switching circuit according to claim 3, wherein the constant voltage means is a rectifier.

(5) The switch according to claim 3, wherein the constant voltage means is connected to an emitter of the bipolar transistor Q1. Circuit.

(6) The switching circuit according to claim 5, wherein the constant voltage means is a rectifier.

(7) The switching circuit according to claim 3, wherein the constant voltage means is connected to the base of the bipolar transistor Q1.

(8) The switching circuit according to claim 7, wherein the constant voltage means is a rectifier.

(9) The constant voltage means is an emitter-junction of a bipolar-transistor Q2, and the base is connected to the emitter of the bipolar-transistor QL, and the bipolar transistors Q1 and Q2 are Darlington-connected. 3. The switching surface according to claim 3, wherein:

(10) The switching circuit according to (1) or (2), wherein the bipolar transistor Q1 is formed of a plurality of Darlington-connected bipolar transistors.