JP3932423B2 - Discharge lamp lighting device and lighting fixture - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a discharge lamp lighting device and a lighting fixture for lighting a discharge lamp at high frequency.
[0002]
[Prior art]
FIG. 17 shows a circuit diagram of a conventional discharge lamp lighting device.
In the figure, 1 is an AC power source, 2 is a noise filter, 3 is a power supply circuit comprising a voltage doubler rectifier circuit constituted by diodes 3b and 3c and smoothing capacitors 3e and 3f, and 4 is a MOSFET incorporating a regenerative diode (hereinafter referred to as switching element). A switching circuit 5 consisting of a half bridge composed of 4a, 4b and a driver 4c, 5 is composed of a discharge lamp (hereinafter referred to as a lamp) 5a, a choke coil 5b, a DC cut capacitor 5c, and a starting capacitor 5d. A load circuit 6 is a phase control dimmer.
[0003]
More specifically, the diodes 3b and 3c and the smoothing capacitors 3e and 3f are connected in series with forward polarity, respectively. The cathode of the diode 3b and the positive electrode of the smoothing capacitor 3e, and the anode of the diode 3c and the negative electrode of the smoothing capacitor 3f are connected to each other. Yes. One end of the AC input input via the noise filter 2 is connected to the connection point between the two diodes 3b and 3c, and the other end is connected to the connection point between the two smoothing capacitors 3e and 3f. The lamp 5a and the starting capacitor 5d are connected in parallel, the lamp 5a, the choke coil 5b, and the DC cut capacitor 5c are connected in series, and one end thereof is connected to the output point of the switching circuit 4.
[0004]
Next, the operation will be described with reference to FIG.
In FIG. 17, among the AC inputs input via the noise filter 2, a line connected to the diodes 3b and 3c is referred to as L1, and a line connected to the smoothing capacitors 3e and 3f is referred to as L2.
First, when the potential of L1 is higher than the potential of L2, and the potential difference between the two becomes higher than the charging voltage of the smoothing capacitor 3e, a current flows along the path of L1 → diode 3b → smoothing capacitor 3e → L2, and the smoothing capacitor 3e Charged.
[0005]
When the potential of L2 is higher than the potential of L1 and the potential difference between the two becomes higher than the charging voltage of the smoothing capacitor 3f, a current flows through the path of L2 → smoothing capacitor 3f → diode 3c → L1, and the smoothing capacitor 3f is charged. Is done.
The sum of the charging voltages of both the smoothing capacitors 3e and 3f is output as a DC output of the power supply circuit 3. This DC output is applied to the switching circuit 4 and is converted into high-frequency power when the switching element 4a and the switching element 4b driven by the driver 4c are alternately turned ON and OFF. The high-frequency power turns on the lamp 5a while receiving a current limitation by the choke coil 5b.
[0006]
Here, when the lamp is lit by the double voltage rectified voltage, the voltage input to the switching circuit has a margin with respect to the lamp voltage compared to the case of a capacitor input type circuit that smoothes the AC voltage by full-wave rectification. Therefore, it is possible to obtain a wide lamp output simply by changing the switching frequency.
That is, even when the lamp output is reduced, the lamp voltage can be secured, and the lamp can be prevented from flickering or extinguishing. Even when the output is increased, there is an advantage that the switching phase does not advance and can be driven safely. It is a lighting device effective for the power supply.
[0007]
[Problems to be solved by the invention]
However, the conventional discharge lamp lighting device shown in FIG. 17 has the following problems.
First, the smoothing capacitors 3e and 3f are charged for a very short time, and the charge necessary for the circuit is charged within that period. Therefore, the peak of the input current becomes extremely large and the life of the smoothing capacitor is shortened. There was a fear.
FIG. 18C shows the state of the peak of the input current. FIGS. 18A and 18B show the input voltage and output voltage waveforms in the power supply circuit 3 of the discharge lamp lighting device as the input current, respectively. It is the same time axis.
At this time, since the power factor is low, the AC power supply side equipment may be destroyed.
[0008]
Secondly, when a phase-controlled dimmer 6 is connected to the discharge lamp lighting device and the input voltage is phase-controlled, a larger inrush current flows at the moment when the thyristor in the dimmer is turned on. As a result, the life of the smoothing capacitors 3e and 3f is further shortened, and there is a possibility that the components located between the phase control dimmer 6 and the smoothing capacitor 3e or 3f, the diodes 3b and 3c, etc. may be broken.
FIG. 19 (c) shows the state of this inrush current. (A) and (b) are respectively the input voltage and output in the power supply circuit 3 when the input voltage of the discharge lamp lighting device is phase-controlled. The voltage waveform is represented on the same time axis as the input current.
At this time, not only the lighting device but also the dimmer itself may cause malfunction or failure.
[0009]
In order to solve such a problem, a method of improving the power factor by increasing the voltage applied to the switching circuit using an active filter or a transformer as shown in FIGS. 20 and 21, for example, has been proposed.
The main points of these operations will be described with reference to the drawings.
First, in the case of FIG. 20, the AC voltage that has been full-wave rectified by the rectifier circuit 16 is boosted by chopping the coil 17, the switch 18, and the diode 19, and the current flowing through the smoothing capacitor 20 is controlled to improve the power factor. That's it.
Further, in the case of FIG. 21, the power factor is improved by the inductance component of the transformer 21 and the resonance action of the capacitor 22 and the smoothing action of the smoothing capacitor 23.
Problems such as the necessity of a new coil 17 having a size corresponding to the choke coil 5b, the difficulty of downsizing the transformer 21, and the necessity of a large-capacitance capacitor 23 have occurred. As a result, it is difficult to reduce the size of the discharge lamp lighting device, and for example, it is difficult to mount it on a bulb-type fluorescent lamp or the like.
[0010]
Accordingly, the present invention has been made to solve the above-described problems, and a discharge lamp lighting device having an improved power factor by increasing the voltage applied to the switching circuit with a small number of parts. And lighting equipment The purpose is to obtain.
[0013]
[Means for Solving the Problems]
A discharge lamp lighting device according to the present invention includes a power supply circuit that double-rectifies an AC power supply, The first and second switching elements are composed of field effect transistors with built-in regenerative diodes, and the first switching element is connected to the output point of the power supply circuit and the second switching element is connected to the ground. , A switching circuit that converts a DC output of the power supply circuit to a high frequency; and a load circuit that consumes the high frequency output of the switching circuit. The power supply circuit includes first, second diodes, first, Two capacitors and first and second inductors connected in series. The connection point between the cathode of the first diode and the positive electrode of the first capacitor is the output point of the power supply circuit, and the anode of the second diode The connection point between the negative electrode of the second capacitor and the negative electrode of the first capacitor and the positive electrode of the second capacitor are connected to the ground, and the series circuit of the first and second inductors is connected. , Comprising a series circuit of choke coils for limiting the current flowing to the discharge lamp, one end of the AC power supply being connected to the connection point of the first and second inductors, and the other end of the first and second diodes Connected to attachment point, one end of the load circuit connected to the output point of the switching circuit, the other end first, which is constituted so as to be connected to the connection point of the second inductor.
[0014]
Further, the third capacitor is configured to be connected in parallel to the series circuit of the first and second inductors.
[0015]
Further, the first and second inductors are configured to be magnetically coupled.
[0016]
In addition, the first inductor and the second inductor are integrated as a single coil having an intermediate tap, the winding start of the coil winding is set to the negative electrode of the first capacitor, and the winding end of the winding is set to the second winding. Or the end of the winding of the coil is connected to the negative of the first capacitor, the start of the winding is connected to the positive of the second capacitor, and the intermediate tap of the coil is connected to the load circuit It is configured to be connected to the other end.
[0017]
In addition, the first and second inductors and the choke coil are magnetically coupled.
[0021]
Furthermore, above The lighting apparatus is configured to use a bent fluorescent lamp having a discharge lamp lighting device.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 shows a circuit diagram of a discharge lamp lighting device according to Embodiment 1 of the present invention. The description of the same points as in the conventional circuit configuration shown in FIG. 17 will be omitted, and different points will be described.
In the power supply circuit 3, diodes 3a and 3d are added. First, the diode 3a is disposed between the diode 3b and the smoothing capacitor 3e, and the anode and cathode of the diode 3a are connected to the cathode of the diode 3b and the positive electrode of the smoothing capacitor 3e, respectively. The diode 3d is disposed between the diode 3c and the smoothing capacitor 3f, and the cathode and anode of the diode 3d are connected to the anode of the diode 3c and the negative electrode of the smoothing capacitor 3f, respectively.
[0023]
Next, in the load circuit 5, the end of the load circuit 5 in which the lamp 5a and the choke coil 5b are connected in series and the starting capacitor 5d is connected in parallel to the lamp 5a is connected to two DC cut capacitors 9, 10 and capacitors of equal capacity. 11 are connected to the anode of the diode 3a, the cathode of the diode 3d, and the positive electrode of the smoothing capacitor 3f. Yes.
[0024]
Next, the operation will be described with reference to FIG.
First, the operation when the capacitor 11 is not connected will be described.
The power source circuit 3 performs voltage doubler rectification, converts this DC output into a high frequency by the switching circuit 4, and turns on the lamp 5a in the load circuit 5 while limiting the current by the choke coil 5b. Since there is, explanation is omitted. A current flow in the case of 0 <V0 will be described.
[0025]
(1) When switching element 4a is ON
The electric energy stored in the smoothing capacitor 3e until then is discharged, and a current flows through the loop of the switching element 4a → the lamp 5a → the choke coil 5b → the DC cut capacitor 9 → the diode 3a → the switching element 4a.
(2) When the regenerative diode of switching element 4b is ON
The smoothing capacitor 3e → smoothing capacitor 3f → ground → regenerative diode of the switching element 4b → lamp 5a → choke coil 5b → DC cut capacitor 9 → diode 3a → smoothing capacitor 3e by the electrical energy stored in the choke coil 5b in the previous period Current flows in the loop.
(3) When switching element 4b is ON
When the electric energy stored in the choke coil 5b is lost in the previous period, the AC power source 1 → diode 3b → DC cut capacitor 9 → choke coil 5b → lamp 5a → switching element 4b → ground → smoothing capacitor 3f → AC power source 1 loop Current flows through
(4) When the regenerative diode of switching element 4a is ON
The electric energy stored in the choke coil 5b in the previous period is discharged, and the choke coil 5b → the lamp 5a → the regenerative diode of the switching element 4a → the smoothing capacitor 3e → the AC power source 1 → the diode 3b → the DC cut capacitor 9 → the choke coil 5b Current flows in the loop.
[0026]
The above operation is the same for the current around the smoothing capacitor 3f when V0 <0. As a result, an input waveform as shown in FIG. 2C can be obtained.
Comparing this input current waveform with the conventional waveform shown in FIG. 18C, it can be seen that the peak is reduced and the current is leveled.
[0027]
In FIG. 2, (a), (b), (d), (e), and (f) are phase control type dimming in the discharge lamp lighting device of Embodiment 1 to which the capacitor 11 is not connected. The input voltage and output voltage waveforms in the power supply circuit 3 when the dimming function of the light source 6 is turned off, the waveforms of the currents i1 and i3 flowing through the smoothing capacitors 9 and 10, and the waveform of the current i1 flowing through the lamp 5a are input. It is the same time axis as the current.
A relationship of i1 = i2 + i3 is established between the lamp current i1 and the currents i2 and i3 flowing through the DC cut capacitors 9 and 10.
[0028]
Next, the case where the capacitor 11 is connected will be described.
In this case, the capacitor 11 having a smaller capacity than the capacitors 9 and 10 is selected. When viewed from the end of the load circuit 5, the impedance of the capacitor 11 is small, and the amplitude of the potential difference between V4 and V2 is maximized near the zero cross of the AC voltage, so the current i4 flowing through the capacitor 11 is also maximized here.
Further, a relationship of i1 = i2 + i3 + i4 is established between the current i4 flowing through the capacitor 11 and the lamp current and the currents i1, i2, and i3 flowing through the DC cut capacitors 9 and 10.
[0029]
Therefore, from these results, an input waveform as shown in FIGS. 3C and 4C can be obtained.
Comparing these input current waveforms with the conventional waveforms shown in FIG. 18C or FIG. 19C, it can be seen that the peak is reduced and the current is leveled.
[0030]
In FIG. 3, (a), (b), (d), (e), (f), (g), and (h) are the discharge lamp lighting device of the first embodiment to which the capacitor 11 is connected, respectively. , The waveforms of the input voltage and output voltage in the power supply circuit 3 when the dimming function of the phase control dimmer 6 is turned off, the waveform of the termination voltage V4 of the load circuit 5, and the current flowing through the smoothing capacitors 9, 10 The waveforms of i2 and i3, the waveform of the current i4 flowing through the capacitor 11, and the waveform of the current i1 flowing through the lamp 5a are represented on the same time axis as the input current.
[0031]
4A and 4B, the discharge lamp lighting device of the first embodiment to which the capacitor 11 is connected, respectively, is adjusted by setting the phase angle of the phase control dimmer 6 to about 45 degrees. The waveform of the input voltage in the power supply circuit 3 at the time of lighting and the output voltage is represented on the same time axis as the input current.
[0032]
In this way, the load current is fed back to the AC power supply and the smoothing capacitor via the DC cut capacitor, so that the current flowing from the AC power supply to the smoothing capacitor is dispersed at a high frequency, thus reducing the inrush current. And improve the power factor.
Furthermore, by connecting the capacitor 11 in addition to the connection of the DC cut capacitors 9 and 10, the ripple of the lamp current can be reduced and the luminous efficiency can be improved.
[0033]
Further, due to the operation of the capacitor 11, even in the vicinity of the zero cross, if 0 <V 0, the current i 4 is changed from the AC power source 1 → the diode 3 b → the diode 3 a → Switching element 4a → choke coil 5b → It flows along the path of the capacitor 11 → the AC power source 1.
[0034]
If V0 <0, AC power source 1 → capacitor 11 → choke coil 5b → switching element 4b → diode 3d → Diode 3 c → Since it flows through the path of the AC power source 1, in addition to the operation of the DC cut capacitors 9 and 10, the power factor can be further increased.
[0035]
In this embodiment, the capacitor 11 is connected between the end of the load circuit and the positive electrode of the smoothing capacitor 3f. However, the same effect can be obtained by connecting an impedance element such as a resistor or an inductor or a switching element.
[0036]
Embodiment 2. FIG.
FIG. 5 shows a circuit diagram of a discharge lamp lighting device according to Embodiment 2 of the present invention. Description of points that are the same as the circuit configuration of the conventional example or the first embodiment will be omitted, and different points will be described.
In the figure, the load circuit 5 is configured such that the choke coil 5b is provided with an intermediate tap 5e, and the DC cut capacitors 9, 10 are connected to the intermediate tap 5e.
Further, the AC power supply 1, noise filter 2, power supply circuit 3, switching circuit 4, lamp 5a, starting capacitor 5d and capacitor 11 have the same configuration and operation as those of the first embodiment, and therefore description thereof is omitted.
[0037]
In the present embodiment, the power factor and the ripple of the lamp current are set by optimizing the division ratio of the intermediate tap 5e and the capacitance of the capacitor 9, and the degree of design freedom is higher than that of the first embodiment. It has spread.
The operation is the same as that of the first embodiment, and the voltage / current waveforms are the same as those shown in FIGS.
[0038]
As described above, since the load current is fed back to the AC power supply and the smoothing capacitor via the DC cut capacitor, the current flowing from the AC power supply to the smoothing capacitor is dispersed at high frequency. It can be reduced and the power factor can be improved.
[0039]
Further, since the lamp 11 can be secured even near the zero cross of the AC power supply by the capacitor 11, the ripple of the lamp current can be reduced.
Furthermore, since the factors that determine the power factor and lamp current ripple increase, the optimum design can be facilitated.
[0040]
As shown in FIG. 6, the same effect can be obtained by connecting the DC cut capacitors 9 and 10 to the end of the choke coil 5b and connecting the capacitor 11 to the intermediate tap 5e.
As shown in FIG. 7, the same effect can be obtained by connecting the capacitor 11 between the connection point of the lamp 5a and the choke coil 5b and the positive electrode of the smoothing capacitor 3f.
Furthermore, the same effect can be obtained even if the choke coil 5b is provided on the switching circuit 4 side as shown in FIG.
[0041]
Embodiment 3 FIG.
FIG. 9 shows a circuit diagram of a discharge lamp lighting device according to Embodiment 3 of the present invention. Description of points that are the same as those of the conventional or first and second embodiments will be omitted, and different points will be described.
In the figure, a power supply circuit 3 has a series connection of a smoothing capacitor 3e, an inductor 3h, an inductor 3i and a smoothing capacitor 3f connected in parallel to a series circuit of diodes 3b and 3c, and one end of an AC power supply 1 is connected to a connection point of the diodes 3b and 3c. In addition, the other end and the end of the load circuit 5 are connected to the connection point of the inductors 3h and 3i.
The AC power source 1, noise filter 2, switching circuit 4, and load circuit 5 have the same configuration and operation as those of the first embodiment, and thus the description thereof is omitted.
[0042]
Next, the operation will be described with reference to FIG.
The voltage at point 3g viewed from the connection point of both inductors 3h and 3i is V0, the voltage across smoothing capacitor 3e is V1, the voltage across inductor 3h is V5, and the sum of V1 and V5 is V6.
A current flow in the case of 0 <V0 will be described.
[0043]
(1) When switching element 4a is ON
The electric energy stored in the smoothing capacitor 3e so far is discharged, and a current flows through the loop of the switching element 4a → the lamp 5a → the choke coil 5b → the inductor 3h → the smoothing capacitor 3e.
(2) When the regenerative diode of switching element 4b is ON
Due to the electrical energy stored in the choke coil 5b in the previous period, a current flows through a loop of ground → regenerative diode of the switching element 4b → lamp 5a → choke coil 5b → inductor 3i → smoothing capacitor 3f.
(3) When switching element 4b is ON
A current flows through the loop of smoothing capacitor 3f → inductor 3i → choke coil 5b → lamp 5a → switching element 4b → ground.
(4) When the regenerative diode of switching element 4a is ON
Electric energy stored in the choke coil 5b is discharged, and a current flows through the loop of the choke coil 5b → the lamp 5a → the regenerative diode of the switching element 4a → the smoothing capacitor 3e → the inductor 3h.
[0044]
If the oscillation frequency of the driver 4c is f and the amplitude is α1,
The relationship V6 = V1 + α1 · sin (2πft) holds.
Here, the magnitude of α1 is determined by the inductance values of the choke coil 5b and the inductor 3h.
As a result, the period in which V0 <V6 is dispersed in a high frequency, and the power factor can be improved.
[0045]
The above operation is the same for the current around the smoothing capacitor 3f when V0 <0. As a result, an input current waveform as shown in FIG. 10C can be obtained. Comparing this input current waveform with the conventional waveform shown in FIG. 18C, it can be seen that the peak is reduced and the current is leveled.
[0046]
10, (a) and (b) are respectively the input voltage in the power supply circuit 3 when the dimming function of the phase control dimmer 6 is turned off in the discharge lamp lighting device of the third embodiment. The waveform of the output voltage is represented on the same time axis as the input current.
[0047]
Further, as shown in FIG. 11, the inductor 3h and 3i shown in FIG. 9 may be magnetically coupled and an integrated coil 3j may be used. Further, as shown in FIG. 12, the secondary winding is provided around the choke coil 5b. 5f and 5g may be provided to have the same effect as the inductors 3h and 3i. When the inductors 3h and 3i are magnetically coupled, the coil 3j is designed so that both have opposite polarities when viewed from the connection point of the load circuit 5.
Furthermore, FIG. Shown in Inductor 5b Or for secondary windings 5f and 5g As shown in FIG. By connecting in parallel, the power factor can be further improved by the resonant action of the capacitor 12 and the inductor.
[0048]
As described above, since the diodes 3b and 3c are switched at a high frequency, the period during which the input current flows can be dispersed and the power factor can be improved.
[0049]
Embodiment 4 FIG.
FIG. 15 shows a circuit diagram of a discharge lamp lighting device according to Embodiment 4 of the present invention. Description of points that are the same as those of the conventional example or the circuit configurations of the first, second, and third embodiments will be omitted, and different points will be described.
In the figure, a choke coil 5b has secondary windings 5h and 5i. One end of the secondary winding 5h is on the output side of the power supply circuit 3, and the other end is a capacitor. 8 Is connected to the anode of the diode 3a. Similarly, one end of the secondary winding 5i is on the ground side and the other end is a capacitor. 9 To the cathode of the diode 3d.
[0050]
In the switching circuit 4, the switching element 4a is a P-channel MOSFET, the switching element 4b is an N-channel MOSFET, and both drain terminals are connected in common to serve as an output terminal. The switching element 4a takes in the output of the secondary winding 5h as a gate signal through the impedance element 4d, and the switching element 4b takes in the output of the secondary winding 5i as a gate signal through the impedance element 4e. Reference numerals 4f, 4g, 4h and 4i denote constant voltage diodes for protecting the switching elements 4a and 4b, and 4j denotes a starting circuit.
The AC power supply 1, noise filter 2, and power supply circuit 3 are the same in configuration and operation as those in the first embodiment, and thus the description thereof is omitted.
[0051]
Since the principle relating to the power factor improvement is the same as that of the first embodiment, a description thereof will be omitted. The operation of the switching circuit 4 is different, and this point will be described.
The switching element 4a or 4b is first turned on by the starting circuit 4j, and self-oscillation is started. In a stable operation after starting the oscillation, the voltage V7 generated in the secondary winding 5h is based on the output point of the power supply circuit 3 and the amplitude is α2 and the switching frequency is f.
V7 = α2 · sin (2πft)
It becomes. On the other hand, the voltage V8 of the secondary winding 5i has the same switching frequency f when the amplitude is α3 with respect to the ground.
V8 = α3 · sin (2πft)
It becomes.
[0052]
(1) When 0 <V7, V8
Switching element 4a is OFF, 4b is ON,
(2) When V7, V8 <0
The switching element 4a is turned on and 4b is turned off.
Thereby, the switching elements 4a and 4b are alternately turned ON / OFF.
When the impedance elements 4d and 4e are resistors, V7 <0 <V8, or vice versa, V8 <0 <V7 cannot be established, and both switching elements 4a and 4b cannot be turned on at the same time. When the elements 4d and 4e are, for example, inductors, it is necessary to appropriately select the constant voltage diodes 4f, 4g, 4h, and 4i so as to avoid the above-described state.
[0053]
As described above, the high-frequency output portion of the load circuit 5 is connected to the AC power source 1 and the smoothing capacitors 3e and 3f by the capacitors 7 and 8, and the current flowing from the AC power source to the smoothing capacitor is dispersed in a high frequency manner. As a result, the inrush current can be reduced, the power factor can be improved, and both the components required for the power factor improvement and the components constituting the drive unit of the switching circuit 4 can be used. .
[0054]
Embodiment 5 FIG.
FIG. 16 is a schematic front view showing a state in which the discharge lamp lighting device according to the present invention is incorporated in a bulb-type fluorescent lamp device. Description of points that are the same as those of the conventional example or the first, second, third, and fourth embodiments will be omitted, and different points will be described.
In the figure, 13 is a base, 14a is a cover, 14b is a globe, and 15 is a circuit board on which a discharge lamp lighting device corresponding to any one of the first to fifth embodiments is mounted.
The lamp 5b is a bent fluorescent lamp, and the lamp 5b, the base 13, the cover 14a, the globe 14b, and the circuit board 15 are integrated to constitute a light bulb type fluorescent lamp device.
Since the circuit board 15 can be configured with a small number of parts, it can be incorporated into a light bulb-type fluorescent lamp as shown in the figure, and a light bulb-type fluorescent lamp device corresponding to a phase control dimmer can be obtained.
[0055]
【The invention's effect】
Since this invention is comprised as mentioned above, there exists an effect as shown below.
[0058]
Book According to the invention, since the diodes constituting the voltage doubler rectifier circuit can be switched in accordance with the operation of the switching circuit, the period during which the input current flows can be increased without increasing the number of diodes constituting the voltage doubler rectifier circuit. Can be dispersed and the power factor can be improved.
[0059]
Also book According to the invention, since the two inductors and the capacitor required for power factor improvement are made to resonate, an inductor having a smaller inductance than that of the invention of claim 6 can be used. It can be downsized.
[0060]
Also book According to the invention, since the two inductors necessary for power factor improvement are magnetically coupled, the number of components can be further reduced and the apparatus can be downsized.
[0061]
Also book Invention According to The power factor can be further improved by appropriately setting the polarity of the magnetic coupling.
[0062]
Also book According to the invention, since the two inductors necessary for power factor improvement and the choke coil for reducing the lamp current are magnetically coupled, the number of parts can be further reduced and the apparatus can be miniaturized.
[0066]
Moreover, according to the present invention, , above Since it is configured to be a lighting fixture using a bent fluorescent lamp having a discharge lamp lighting device, a compact and highly efficient bulb-type fluorescent lamp device can be obtained.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of a discharge lamp lighting device according to Embodiment 1 of the present invention.
FIG. 2 shows voltage / current waveforms in the power supply circuit when the dimming function of the phase control dimmer 6 is turned off in the discharge lamp lighting device according to the first embodiment of the present invention to which the capacitor 11 is not connected. Is shown.
FIG. 3 shows voltage / current waveforms in the power supply circuit when the dimming function of the phase control dimmer 6 is turned off in the discharge lamp lighting device according to the first embodiment of the present invention to which the capacitor 11 is connected. It is shown.
FIG. 4 shows voltage / current waveforms in the power supply circuit when the phase angle of the phase control dimmer 6 is set to 45 degrees in the discharge lamp lighting device according to Embodiment 1 of the present invention to which the capacitor 11 is connected. It is shown.
FIG. 5 shows a first circuit diagram of a discharge lamp lighting device according to Embodiment 2 of the present invention.
FIG. 6 shows a second circuit diagram of the discharge lamp lighting device according to Embodiment 2 of the present invention.
FIG. 7 shows a third circuit diagram of the discharge lamp lighting device according to Embodiment 2 of the present invention.
FIG. 8 shows a fourth circuit diagram of the discharge lamp lighting device according to Embodiment 2 of the present invention.
FIG. 9 shows a first circuit diagram of a discharge lamp lighting device according to Embodiment 3 of the present invention.
FIG. 10 shows voltage / current waveforms in the power supply circuit when the dimming function of the phase control dimmer 6 is turned off in the discharge lamp lighting device according to Embodiment 3 of the present invention.
FIG. 11 shows a second circuit diagram of the discharge lamp lighting device according to Embodiment 3 of the present invention.
FIG. 12 shows a third circuit diagram of the discharge lamp lighting device according to Embodiment 3 of the present invention.
FIG. 13 shows a fourth circuit diagram of the discharge lamp lighting device according to Embodiment 3 of the present invention.
14 (a), (b), and (c) are main part explanatory diagrams for fifth, sixth, and seventh circuit examples of the discharge lamp lighting device according to Embodiment 3 of the present invention, respectively.
FIG. 15 is a circuit diagram of a discharge lamp lighting device according to Embodiment 4 of the present invention.
FIG. 16 is a schematic front view of a bulb-type fluorescent lamp incorporating a discharge lamp lighting device according to the present invention.
FIG. 17 is a circuit diagram of a first conventional discharge lamp lighting device.
FIG. 18 shows voltage / current waveforms of a power supply circuit in the first conventional discharge lamp lighting device.
FIG. 19 shows voltage / current waveforms in the power supply circuit when the phase control dimmer is dimmed in the first conventional discharge lamp lighting device.
FIG. 20 is a circuit diagram of a second conventional discharge lamp lighting device.
FIG. 21 is a circuit diagram of a third conventional discharge lamp lighting device.
[Explanation of symbols]
1 AC power supply
3 Power supply circuit
3a, 3b, 3c, 3d diode
3e, 3f smoothing capacitor
3h, 3i inductor
3j coil
4 Switching circuit
4a, 4b switching element
4c driver
4d, 4e impedance element
4f, 4g, 4h, 4i constant voltage diode
4j Start-up circuit
5 Load circuit
5a lamp
5b Choke coil
5c, 9, 10 DC cut capacitor
5e Middle tap
5f, 5g, 5h, 5i secondary winding
7, 8, 11, 12 Capacitor
13 Base
14a cover
14b gloves
15 Circuit board

Claims (6)

A power supply circuit for voltage rectifying the AC power supply;
A half bridge in which the first and second switching elements are composed of a field effect transistor with a built-in regenerative diode, and the first switching element is connected to the output point of the power supply circuit and the second switching element is connected to the ground. configuration and then, a switching circuit for converting the DC output of the power supply circuit to a high frequency,
A load circuit that consumes the high-frequency output of the switching circuit,
The power supply circuit includes first and second diodes connected in forward polarity in series, first and second capacitors, and first and second inductors connected in series, and the cathode of the first diode and the The connection point between the positive electrode of the first capacitor is the output point of the power supply circuit, the connection point between the anode of the second diode and the negative electrode of the second capacitor is the ground, and the negative electrode of the first capacitor A series circuit of the first and second inductors is connected between the positive electrodes of the second capacitors;
The load circuit comprises a series circuit of a discharge lamp and a choke coil that limits a current flowing through the discharge lamp,
One end of the AC power source is connected to a connection point of the first and second inductors, and the other end is connected to a connection point of the first and second diodes.
One end of the load circuit is connected to an output point of the switching circuit, and the other end is connected to a connection point of the first and second inductors. The first, the discharge lamp lighting device according to claim 1, characterized in that connected in parallel a third capacitor series circuit of the second inductor. The first discharge lamp lighting apparatus according to claim 1 or 2, wherein the second inductor is characterized in that is magnetically coupled. The first inductor and the second inductor are integrated as a single coil having an intermediate tap, and the winding start of the coil is set to the negative electrode of the first capacitor, and the winding end of the winding is set. Connecting to the positive electrode of the second capacitor, or connecting the winding end of the coil to the negative electrode of the first capacitor and the winding start of the winding to the positive electrode of the second capacitor;
The discharge lamp lighting device according to claim 3 , wherein an intermediate tap of the coil is connected to the other end of the load circuit. The first discharge lamp lighting apparatus according to claim 1 or 2, wherein the said choke coil and the second inductor were magnetically coupled. Lighting fixture using a bent fluorescent lamp having any of the discharge lamp lighting apparatus of claims 1 5.

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