JP3555637B2 - Power supply device, discharge lamp lighting device and lighting device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power supply device, a discharge lamp lighting device, and a lighting device in which an input power factor from an AC power supply is improved and distortion of an input current is reduced.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a discharge lamp lighting device of this type, a configuration described in, for example, Japanese Patent Application Laid-Open No. Hei 5-174986 is known.
[0003]
In the configuration described in Japanese Patent Application Laid-Open No. HEI 5-174948, a small-capacity capacitor is connected to the output side of a full-wave rectifier connected to a commercial AC power supply via a resonance coil and a resonance capacitor for resonance. Is connected to a half-bridge type inverter circuit in which switching elements are connected in series.
[0004]
Then, during the ON period of the high-voltage side switching element, the inverter circuit is initially supplied with power from a small-capacity capacitor, and since this capacitor has a small capacity, the voltage soon drops, and after discharging this capacitor, the commercial AC power supply Apply current.
[0005]
In the off period of the switching element on the high voltage side, the inflow current is cut off to generate a resonance voltage resonated by the resonance coil and the resonance capacitor, and the resonance current is supplied to the capacitor.
[0006]
Then, the input current is made to flow even during a period in which the input voltage from the commercial AC power supply is low, so that a high input power factor and a low distortion of the input current are achieved.
[0007]
[Problems to be solved by the invention]
Then, considering a specific circuit based on the configuration described in JP-A-5-174986, for example, a configuration as shown in FIG.
[0008]
FIG. 4 is a circuit diagram of a discharge lamp lighting device that can be considered based on the conventional example. In the discharge lamp lighting device 1, a filter circuit 2 is connected to a commercial AC power supply e via a fuse F. It is composed of an absorbing element TNR1, a capacitor C1, a transformer Tr1, an inductor L1, a capacitor C2, and a surge absorbing element TNR2. A full-wave rectifier circuit 3 is connected to the filter circuit 2, and the full-wave rectifier circuit 3 has high-speed switching characteristics. The full-wave rectifier circuit 3 further includes a series circuit of a capacitor C3 for preventing noise and a capacitor C4 connected to a frame (not shown). Is done.
[0009]
A series circuit of a first transistor Q1 and a second transistor Q2 having a smoothing action on the output frequency of the full-wave rectifier circuit 3 is connected in parallel with the full-wave rectifier circuit 3, and the first transistor A circulating diode D5 is connected between the collector and the emitter of Q1, and a parallel circuit of a circulating diode D6 and a capacitor C5 is connected between the collector and the emitter of the second transistor Q2.
[0010]
Furthermore, a series circuit of a first capacitor C6 and a second capacitor C7 is connected in parallel with the full-wave rectifier circuit 3, and a connection point of the first transistor Q1 and the second transistor Q2 is Between the connection point of the capacitor C6 and the second capacitor C7, a saturable current transformer composed of a primary winding Tr2a of a leakage isolation type output transformer Tr2 also having a function as a current limiting impedance and a saturable reactor. The series circuit of the input winding CTa of the device CT is connected.
[0011]
A series circuit of a diode D7 and a resistor R1 is connected between the base and the emitter of the first transistor Q1, and a resistor R3, a first output winding CTb of the saturable current transformer CT, a diode D8, A series circuit of a parallel circuit of a capacitor C8 is connected, a capacitor C9, a drain and a source of a field effect transistor Q3 are connected in parallel with the capacitor C8, and a parallel circuit of a resistor R4 and a capacitor C11 is connected between a gate and a source. Have been.
[0012]
Further, a starting circuit 4 is connected between both terminals of the full-wave rectifier circuit 3. The starting circuit 4 has a series circuit of a resistor R5, a resistor R6 and a capacitor C12. The connection point of the resistor R6 and the capacitor C12 always discharges the charge of the capacitor C12 to prevent the diac Q4 from operating. Connected to the connection point of the first transistor Q1 and the second transistor Q2 via a diode D11, and has a diac Q4 and a resistor R7. The diac Q4 is connected to the second transistor Q3 via a resistor R7. It is connected to the base of Q2. The diode D11 always discharges the charge of the capacitor C12 to prevent the diac Q4 from operating.
[0013]
Furthermore, a series circuit of a diode D12 and a resistor R8 is connected between the base and the emitter of the second transistor Q2, and a second output winding CTc of the saturable current transformer CT is connected via a resistor R11. A diode D13 and a parallel circuit of a capacitor C13 are connected in series.
[0014]
Further, between the two terminals of the full-wave rectifier circuit 3, five resistors R12, R14, R15, R16 are connected in series, and a capacitor C15 is connected in parallel with the series circuit of the resistors R14, R15, R16. I have. Further, the emitter and collector of the transistor Q5 and the capacitor C16 are connected in parallel with the capacitor C15, and the base of the transistor Q5 is connected to the negative electrode of the full-wave rectifier circuit 3 via the Zener diode ZD11. The connection point between the collector of the transistor Q5 and the capacitor C16 is connected to the gate of the field effect transistor Q3 via the resistor R14 and the diode D15.
[0015]
Further, a series circuit of resistors R18, R20, R21 and a diode D16 is connected between both terminals of the full-wave rectifier circuit 3, and a capacitor C17 is connected in parallel with the resistors R20, D16 and R21. . The base of the transistor Q6 is connected to the connection point between the resistor R20 and the diode D16, the collector of the transistor Q6 is connected to the resistor R15 via the resistor R22, and the emitter of the transistor Q6 is connected to the full-wave rectifier circuit via the resistor R23. 3, a capacitor C18 is connected between the emitter and the collector of the transistor Q6 via the resistor R23. Further, a connection point between the collector of the transistor Q6 and the resistor R22 is connected to a field-effect transistor Q7 via a resistor R24. The drain of the field-effect transistor Q7 is connected to a second node via a series circuit of a resistor R25 and a capacitor C19. The source is connected to the connection point between the output winding CTc and the capacitor C13, and the source is connected to the negative electrode of the full-wave rectifier circuit 3.
[0016]
On the other hand, the secondary winding Tr2b of the output transformer Tr2 as an output circuit is connected to the filament FL1a of the fluorescent lamp FL1 and the filament FL2b of the fluorescent lamp FL2 as loads. The filament winding Tr2c of the transformer Tr1 is connected to the filament FL1b of the fluorescent lamp FL1 and the filament FL2a of the fluorescent lamp FL2. The starting capacitor C22 is connected between the filament FL1a and the filament FL2b of the fluorescent lamp FL1, and the filament FL1b of the fluorescent lamp FL1 and the filament FL2a of the fluorescent lamp FL2 are connected to the filament winding Tr2c of the output transformer Tr2. ing.
[0017]
Next, the operation of the circuit of the power supply device will be described.
[0018]
First, when the power is turned on, the output voltage of the full-wave rectifier circuit 3 charges the capacitor C12 via the resistors R5 and R6. When the charging voltage of the capacitor C12 exceeds the breakover voltage of the diac Q4, the charge of the capacitor C12 is discharged through the diac Q4 and the resistor R7, and a base current as a start trigger signal to the base of the transistor Q2 is generated. The transistor Q2 is turned on. In this way, when the second transistor Q2 is turned on, the positive output terminal of the full-wave rectifier circuit 3, the first capacitor C6, the primary winding Tr2a of the output transformer Tr2, and the input winding of the saturable current transformer CT. A current flows through CTa, the path of the collector and emitter of the second transistor Q2, and the path of the negative output terminal of the full-wave rectifier circuit 3. Then, when the first capacitor C6 is charged, voltages of opposite polarities appear on the first output winding CTb and the second output winding CTc of the saturable current transformer CT, and the saturable current transformer CT saturates. , The ON and OFF of the first transistor Q1 and the second transistor Q2 are inverted.
[0019]
That is, when the second transistor Q2 is turned off, the current is stored in the primary winding Tr2a of the output transformer Tr2 by the energy stored in the primary winding Tr2a, the input winding CTa of the saturable current transformer CT, and the diode D5. , Flows through the path of the first capacitor C1 and the primary winding Tr2a of the output transformer Tr2. Thereafter, when the first transistor Q1 is turned on, the electric charge stored in the first capacitor C6 is transferred to the first capacitor C1, the collector and the emitter of the first transistor Q1, and the input winding of the saturable current transformer CT. The line CTa flows through the path of the primary winding Tr2a of the output transformer Tr2 and the first capacitor C6.
[0020]
When the first transistor Q1 turns off due to the saturation of the saturable current transformer CT, the diode D6 turns on, and the primary winding Tr2a of the output transformer Tr2 and the second capacitor C7 resonate in series, and the resonance current decreases. The current flows through the primary winding Tr2a of the output transformer Tr2, the second capacitor C7, the diode D6, the input winding CTa of the saturable current transformer CT, and the primary winding Tr2a of the output transformer Tr2. Thereafter, when the second transistor Q2 is turned on, the polarity of the resonance current is reversed and the resonance current is reversed. That is, the primary winding Tr2a of the output transformer Tr2, the input winding CTa of the saturable current transformer CT, the collector and emitter of the second transistor Q2, the second capacitor C7, and the primary winding Tr2a of the output transformer Tr2. Flows. Further, the resonance voltage in the feedback in which the resonance current flows through the primary winding Tr2a of the output transformer Tr2 and the second capacitor C7 is larger than the rectified pulsating voltage of the full-wave rectification circuit 3 because the resistance component of the resonance circuit is small. That is, the voltage is increased.
[0021]
Then, since the resonance voltage decreases and the voltage between both ends of the second capacitor C7 and the first capacitor C6 also decreases, the positive electrode of the full-wave rectifier circuit 3, the first capacitor C1, and the primary winding Tr2a of the output transformer Tr2. , The input winding CTa of the saturable current transformer CT, the second transistor Q2, and the negative electrode of the full-wave rectifier circuit 3.
[0022]
Next, when the second transistor Q2 is turned off, the diode D5 is turned on and the primary winding Tr2a of the output transformer Tr2, the diode D5, the first capacitor C1, and the output are stored by the energy stored in the primary winding Tr2a of the output transformer Tr2. A current flows through the primary winding Tr2a of the transformer Tr2, and this operation is repeated.
[0023]
As described above, a high-frequency current of about several tens of kHz flows through the primary winding Tr2a of the output transformer Tr2, and the fluorescent lamps FL1 and FL2 connected to the secondary winding Tr2b are turned on.
[0024]
Here, after the first transistor Q1 and the second transistor Q2 enter self-excitation, the first transistor Q1 and the second transistor Q2 alternately at a high frequency of about several tens kHz, which is much higher than the power supply frequency. When the second transistor Q2 is turned on by turning on and off, the potential at the connection point between the first transistor Q1 and the second transistor Q2 drops to the reference potential, so that the output voltage of the full-wave rectifier circuit 3 becomes a capacitor. Even if the capacitor C12 is charged, the charge of the capacitor C12 is discharged through the diode D11 and cannot exceed the breakover voltage of the diac Q4. Therefore, a start trigger signal is input to the base of the second transistor Q2 again. It will not be done. That is, once the second transistor Q2 is turned on, the discharging is performed faster through the diode D11 by the high frequency switching than the charging time constant of the resistors R5 and R6 and the capacitor C12. No start trigger signal is supplied to the second transistor Q2.
[0025]
When the fluorescent lamps FL1 and FL2 are preheated, the capacitor C15 is not charged, so that the transistor Q5 is off and the field-effect transistor Q3 is off, and the capacitor C9 is not connected to the capacitor C8, so that the capacitor C8 is apparently synthesized. Since the capacitance is small, the ON time of the first transistor Q1 is short, the voltage induced in the secondary winding Tr2b of the output transformer Tr2 is low, and the filaments FL1a, FL1b, FL2a, FL2b of the fluorescent lamps FL1, FL2 are preheated. .
[0026]
When the power supply voltage decreases due to, for example, a voltage fluctuation, the current between the collector and the emitter of the transistor Q6 is reduced, and the resistance between the drain and the source of the field effect transistor Q7 is reduced. The combined capacitance of C19 is increased, the on-time of the second transistor Q2 is lengthened, and the output voltage is relatively increased.
[0027]
Conversely, when the power supply voltage decreases, the current between the collector and the emitter of the transistor Q6 is reduced, the resistance between the drain and the source of the field effect transistor Q7 is increased, and the combined capacitance of the capacitor C13 and the capacitor C19 is increased. The on-time of the second transistor Q2 is reduced, and the output voltage is relatively reduced.
[0028]
Therefore, even if the voltage fluctuates due to the voltage fluctuation, the output voltage can be kept constant.
[0029]
However, in the power supply device shown in FIG. 4, when the oscillation is suddenly stopped due to a momentary power failure or the like, the potential of the positive electrode of the full-wave rectifier circuit 3 is VDC, the cathode potential of the diode D11 is VDC−VC1, Assuming that the forward voltage drop of D11 is VD11, the potential of the capacitor C12 is VDC-VC1-VDD12. Here, assuming that the breakover voltage of the diac Q4 is VTH, during the period in which the relationship of VTH> VDC-VC1-VD12 is established, the start trigger signal is not input by the diac Q4, and the start cannot be performed. That is, the capacitor C6 For a few seconds until the charge of the battery is discharged, it does not start even if the power is turned on again.
[0030]
For example, assuming that the commercial AC power supply e is 200 V and the breakover voltage VTH of the diac Q4 is 30 V, the peak value of the full-wave rectified voltage from the full-wave rectifier circuit 3 is about 280 V, and the first transistor Q1 and the second transistor When the transistor Q2 performs the oscillating operation, the charging voltage of the first capacitor C6 becomes 200 V × 1.4 = 280 V at the maximum. Where the first capacitor C6 When the power supply becomes abnormal and the oscillation stops when the charging voltage of the capacitor C becomes 260 V, for example, the forward drop voltage VD11 of the diode D11 is normally 0.6 V, so that the charging potential of the capacitor C12 is at most 280 V- 260V = approximately 20V. Therefore, the potential of the capacitor C12 cannot exceed the breakover voltage 30V of the diac Q4, and the first capacitor C6 There is a problem that the activation trigger signal cannot be supplied to the second transistor Q2 until the charge voltage of the first transistor is discharged to 240V.
[0031]
The present invention has been made in view of the above problems, and has as its object to provide a power supply device, a discharge lamp lighting device, and a lighting device capable of re-oscillation.
[0032]
[Means for Solving the Problems]
A power supply device according to claim 1, comprising: a rectifier for rectifying an output voltage of an AC power supply and outputting a non-smooth DC voltage; and a rectifier which is connected in series and turned on and off alternately to output an output of the rectifier. A pair of switching means for switching at a frequency higher than the output; provided in parallel with the first switching means, and charged by the output of the rectifying means via the second switching means during an ON period of the second switching means. A first capacitor for performing a smoothing action on an output frequency component of the rectifying means and discharging a charge via the first switching means during an ON period of the first switching means; And an inductor interposed between the connection point of the second switching means and the first capacitor, and passing a charge / discharge current of the first capacitor; A second capacitor that resonates with the inductor when the first switching means and the second switching means are turned on and off; and a capacity means charged by the output of the rectification means, and the voltage of the capacity means is equal to or higher than a predetermined value. A starting circuit for operating the second switching means; and a discharging means for discharging the electric charge of the capacity means without passing through the first switching means when the starting circuit turns on the first switching means. The non-smoothing DC voltage of the rectifier is smoothed by the first capacitor, and the resonance voltage generated by the resonance circuit of the second capacitor and the inductor changes the voltage of the first capacitor during one cycle of switching of the pair of switching means. The rectified non-smoothed DC voltage In addition to securing input current even during a low value period to increase the input, lowering the input current to reduce harmonics of the input current, and further comprising a capacitor means charged by the output of the rectifier means. When the voltage of the means becomes equal to or higher than a predetermined value, the first switching means is turned on, and the discharging means discharges the capacity means, so that the restart is reliably performed.
[0033]
A power supply device according to claim 2, wherein the rectifier outputs a non-smooth DC voltage by rectifying the output voltage of the AC power supply; and is connected in series with each other and turned on and off alternately to output the output of the rectifier. A pair of switching means for switching at a frequency higher than the output; provided in parallel with the first switching means, and charged by the output of the rectifying means via the second switching means during an ON period of the second switching means. A first capacitor for performing a smoothing action on an output frequency of the rectifier and discharging a charge through the first switching means during an ON period of the first switching means; An inductor interposed between a connection point of the second switching means and the first capacitor, for passing a charge / discharge current of the first capacitor; A second capacitor that resonates with the inductor in response to turning on and off of the switching means and the second switching means; a capacitance means charged by an output of the rectification means; a diode for discharging a charge of the capacitance means during operation; And an activation circuit for operating any one of the first switching means when the voltage of the capacitance means becomes equal to or higher than a predetermined value. The non-smoothing DC voltage of the means is smoothed, and the voltage of the first capacitor is rectified by the rectifying means during one cycle of switching of the pair of switching means by the resonance voltage generated by the resonance circuit of the second capacitor and the inductor. The peak value of the rectified unsmoothed DC voltage is lower than the unsmoothed DC voltage. In addition to securing the input current and increasing the input while reducing the distortion of the input current to reduce the harmonics of the input current, the capacitor further includes a capacitor that is charged by the output of the rectifier. Is greater than or equal to a predetermined value, the first switching means is turned on, and at the time of normal oscillation, the current to the capacitance means is bypassed by the diode via the impedance means, and even when electric charge is stored in the capacitance means, it is ensured. restart.
[0034]
A discharge lamp lighting device according to a third aspect includes the power supply device according to the first and second aspects and a discharge lamp energized and lit by the power supply device, and has respective functions.
[0035]
A lighting device according to a fourth aspect of the present invention includes the discharge lamp lighting device according to the third aspect and a fixture main body provided with the discharge lamp lighting device.
[0036]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a lighting device of the present invention will be described with reference to the drawings.
[0037]
FIG. 2 is a perspective view showing the appearance of the lighting device. As shown in FIG. 2, two pairs of sockets 12 are provided at both ends of the lighting fixture main body 11, and discharge lamps FL1 and FL2 are mounted between these sockets 12. A reflector 13 is attached between the discharge lamps FL1 and FL2, and the discharge lamp lighting device 1 is built therein.
[0038]
FIG. 1 is a circuit diagram showing a discharge lamp lighting device. In the discharge lamp lighting device 1 shown in FIG. 1, the diode D11 is removed from the discharge lamp lighting device shown in FIG. The collector and the emitter of the transistor Q8 as means are connected, and the base of the transistor Q8 is connected to the resistor R7 and the second output winding CTc.
[0039]
Next, the operation of this embodiment will be described.
[0040]
First, when the power is turned on, the output voltage of the full-wave rectifier circuit 3 as the rectifier charges the capacitor C12 via the resistors R5 and R6. When the charging voltage of the capacitor C12 exceeds the breakover voltage of the diac Q4, the charge of the capacitor C12 is discharged through the diac Q4 and the resistor R7, and a base current as a start trigger signal to the base of the transistor Q2 is generated. The transistor Q2 is turned on. In this way, when the second transistor Q2 is turned on, the positive output terminal of the full-wave rectifier circuit 3, the first capacitor C6, the primary winding Tr2a of the output transformer Tr2, and the input winding of the saturable current transformer CT. A current flows through CTa, the path of the collector and emitter of the second transistor Q2, and the path of the negative output terminal of the full-wave rectifier circuit 3. Then, when the first capacitor C6 is charged, voltages of opposite polarities appear on the output windings CTb and CTc of the saturable current transformer CT, and when the saturable current transformer CT is saturated, the first transistor Q1 And the on / off state of the second transistor Q2 is inverted.
[0041]
That is, when the second transistor Q2 is turned off, the current is stored in the primary winding Tr2a of the output transformer Tr2 by the energy stored in the primary winding Tr2a, the input winding CTa of the saturable current transformer CT, and the diode D5. , Flows through the path of the first capacitor C1 and the primary winding Tr2a of the output transformer Tr2. Thereafter, when the first transistor Q1 is turned on, the electric charge stored in the first capacitor C6 is transferred to the first capacitor C1, the collector and the emitter of the first transistor Q1, and the input winding of the saturable current transformer CT. The line CTa flows through the path of the primary winding Tr2a of the output transformer Tr2 and the first capacitor C6.
[0042]
When the first transistor Q1 turns off due to the saturation of the saturable current transformer CT, the diode D6 turns on, and the primary winding Tr2a of the output transformer Tr2 and the second capacitor C7 resonate in series, and the resonance current decreases. The current flows through the primary winding Tr2a of the output transformer Tr2, the second capacitor C7, the diode D6, the input winding CTa of the saturable current transformer CT, and the primary winding Tr2a of the output transformer Tr2. Thereafter, when the second transistor Q2 is turned on, the polarity of the resonance current is reversed and the resonance current is reversed. That is, the primary winding Tr2a of the output transformer Tr2, the input winding CTa of the saturable current transformer CT, the collector and emitter of the second transistor Q2, the second capacitor C7, and the primary winding Tr2a of the output transformer Tr2. Flows. Further, the resonance voltage in the feedback in which the resonance current flows through the primary winding Tr2a of the output transformer Tr2 and the second capacitor C7 is larger than the rectified pulsating voltage of the full-wave rectification circuit 3 because the resistance component of the resonance circuit is small. That is, the voltage is increased. In addition, the resonance voltage becomes a power factor improving current, so that distortion can be reduced.
[0043]
Then, since the resonance voltage decreases and the voltage between both ends of the second capacitor C7 and the first capacitor C6 also decreases, the positive electrode of the full-wave rectifier circuit 3, the first capacitor C1, and the primary winding Tr2a of the output transformer Tr2. , The input winding CTa of the saturable current transformer CT, the second transistor Q2, and the negative electrode of the full-wave rectifier circuit 3.
[0044]
Next, when the second transistor Q2 is turned off, the diode D5 is turned on and the primary winding Tr2a of the output transformer Tr2, the diode D5, the first capacitor C1, and the output are stored by the energy stored in the primary winding Tr2a of the output transformer Tr2. A current flows through the primary winding Tr2a of the transformer Tr2, and this operation is repeated.
[0045]
As described above, a high-frequency current of about several tens of kHz flows through the primary winding Tr2a of the output transformer Tr2, and the fluorescent lamps FL1 and FL2 connected to the secondary winding Tr2b are turned on.
[0046]
Here, after the first transistor Q1 and the second transistor Q2 enter self-excitation, the first transistor Q1 and the second transistor Q2 alternately at a high frequency of about several tens kHz, which is much higher than the power supply frequency. When the second transistor Q2 is turned on by turning on and off, the potential at the connection point between the first transistor Q1 and the second transistor Q2 drops to the reference potential.
[0047]
However, since the diac Q4 is not turned on, the transistor Q8 maintains the off state, and the output voltage of the full-wave rectifier circuit 3 is charged in the capacitor C12, so that the voltage of the capacitor C12 rises and exceeds the breakover voltage of the diac Q4. Therefore, a start trigger signal is input to the base of the second transistor Q2. That is, since the capacitor C12 is charged until the diac Q4 is turned on, the start trigger signal is easily supplied to the second transistor Q2 after the restart due to the charge of the capacitor C12.
[0048]
Therefore, even after the power is turned on again, the start can be easily restarted.
[0049]
When the fluorescent lamps FL1 and FL2 are preheated, the capacitor C15 is not charged, so that the transistor Q5 is off and the field-effect transistor Q3 is off, and the capacitor C9 is not connected to the capacitor C8, so that the capacitor C8 is apparently synthesized. Since the capacitance is small, the ON time of the first transistor Q1 is short, the voltage induced in the secondary winding Tr2b of the output transformer Tr2 is low, and the filaments FL1a, FL1b, FL2a, FL2b of the fluorescent lamps FL1, FL2 are preheated. .
[0050]
When the power supply voltage decreases due to, for example, a voltage fluctuation, the current between the collector and the emitter of the transistor Q6 is reduced, and the resistance between the drain and the source of the field effect transistor Q7 is reduced. The combined capacitance of C19 is increased, the on-time of the second transistor Q2 is lengthened, and the output voltage is relatively increased.
[0051]
Conversely, when the power supply voltage decreases, the current between the collector and the emitter of the transistor Q6 is reduced, the resistance between the drain and the source of the field effect transistor Q7 is increased, and the combined capacitance of the capacitor C13 and the capacitor C19 is increased. The on-time of the second transistor Q2 is reduced, and the output voltage is relatively reduced.
[0052]
Therefore, even if the voltage fluctuates due to the voltage fluctuation, the output voltage can be kept constant.
[0053]
Next, another embodiment will be described with reference to FIG.
[0054]
FIG. 3 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. This embodiment is different from the embodiment shown in FIG. 1 in that a capacitor C12 and a second A resistor R31 as an impedance means is connected between the collector of the transistor Q2 and the diode D11 in series.
[0055]
The time constant of the capacitor C12 and the resistor R5 and the resistor R6 when charging the capacitor C12 is made larger than the time constant between the capacitor C12 and the resistor R31 when the capacitor C12 is discharged, thereby preventing malfunction during normal operation. Even when a voltage remains in the capacitor C6, the breakover voltage of the diac Q4 is reliably exceeded, and restarting is ensured even if electric charge is accumulated in the capacitor C12.
[0056]
Note that, in any of the embodiments, the first transistor and the second transistor are not limited to bipolar transistors, and a similar effect can be obtained by using a MOS field effect transistor or an IGBT. When a field-effect transistor is used, the freewheeling diode is not required because the freewheeling diode operates by the parasitic diode of the field-effect transistor itself.
[0057]
The same is true not only when an insulation type transformer is used but also when a direct connection type inductor is used.
[0058]
【The invention's effect】
According to the power supply device of the first aspect, there is provided a capacitor which is charged by the output of the rectifier. Is discharged, so that restart can be surely performed.
[0059]
According to the power supply device of the second aspect, at the time of normal oscillation, the current to the capacitance means is bypassed by the diode via the impedance means, and the restart can be reliably performed even when the electric charge is stored in the capacitance means.
[0060]
According to the discharge lamp lighting device of the third aspect, the discharge lamp energized and lit by the power supply device of the first and second aspects is provided.
[0061]
According to the illuminating device of the fourth aspect, since it has the fixture body provided with the discharge lamp lighting device of the third aspect, the respective effects are exhibited.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing one embodiment of a discharge lamp lighting device according to the present invention.
FIG. 2 is a perspective view showing the lighting device;
FIG. 3 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.
FIG. 4 is a circuit diagram showing a discharge lamp lighting device that can be considered from a conventional example.
[Explanation of symbols]
1 Discharge lamp lighting device
3 Full-wave rectifier circuit as rectifier
4 Start circuit
11 Lighting fixture body
C6 First capacitor
C7 Second capacitor
e Commercial AC power supply
FL1, FL2 Fluorescent lamps as discharge lamps
Q1, Q2 Transistor as switching means
Q8 Transistor as discharge means
R31 Resistance as impedance means
Transformer as Tr2 inductor

Claims (4)

Rectifying means for rectifying the output voltage of the AC power supply and outputting a non-smoothed DC voltage;
A pair of switching means connected in series and alternately turned on and off to switch the output of the rectifying means at a higher frequency than the output of the rectifying means;
It is provided in parallel with the first switching means, is charged by the output of the rectification means via the second switching means during the ON period of the second switching means, and smoothes the output frequency component of the rectification means. And a first capacitor for discharging the charge through the first switching means during the ON period of the first switching means;
An inductor interposed between the connection point of the first switching means and the second switching means and the first capacitor, and passing a charge / discharge current of the first capacitor;
A second capacitor that resonates with the inductor in response to turning on and off of the first switching means and the second switching means;
An activation circuit having capacitance means charged by the output of the rectifying means and activating the second switching means when the voltage of the capacitance means becomes a predetermined value or more;
Discharging means for discharging the electric charge of the capacitance means without passing through the first switching means when the starting circuit turns on the first switching means;
A power supply device comprising: Rectifying means for rectifying the output voltage of the AC power supply and outputting a non-smoothed DC voltage;
A pair of switching means connected in series and alternately turned on and off to switch the output of the rectifying means at a higher frequency than the output of the rectifying means;
It is provided in parallel with the first switching means, is charged by the output of the rectification means via the second switching means during the ON period of the second switching means, and has a smoothing effect on the output frequency of the rectification means. A first capacitor for performing charging and discharging the charge through the first switching means during an ON period of the first switching means;
An inductor interposed between the connection point of the first switching means and the second switching means and the first capacitor, and passing a charge / discharge current of the first capacitor;
A second capacitor that resonates with the inductor in response to turning on and off of the first switching means and the second switching means;
A capacitor that is charged by the output of the rectifier, a diode that discharges the charge of the capacitor during operation, and an impedance that is connected in series to the diode. An activation circuit for operating the first switching means;
A power supply device comprising: A power supply device according to claim 1 or 2;
A discharge lamp energized by the power supply;
A discharge lamp lighting device comprising: A discharge lamp lighting device according to claim 3;
An appliance body provided with the discharge lamp lighting device;
A lighting device, comprising:

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