JP2011171240A - Lighting device, and lighting fixture using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting device in which a user of a lighting fixture can select a fluorescent lamp and a DC lighting source as represented by a light-emitting diode freely and further can use it safely. <P>SOLUTION: The lighting device has a first control means 11 which outputs a driving signal to switching elements Q1, Q2 for driving a discharge lamp La in high frequency through a resonance part 4 and a second control means 12 which outputs a driving signal to a switching element Q3 of a voltage conversion circuit (DC/DC conversion part 5) which steps down output of a DC power supply circuit 1, and is provided with an inductor (preheating transformer T1) having secondary windings n2, n3 for supplying a preheating current to a filament of the discharge lamp La and a rectifier DB which rectifies a voltage of the output end of at least one (secondary winding n2) of the secondary windings n2, n3. The output route of the voltage conversion circuit (DC/DC conversion part 5) and the output route of the rectifier DB are connected in parallel. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a lighting device for performing high-frequency lighting control of a discharge lamp or direct-current lighting control of a light source that is lit with direct current, such as an LED, and a lighting fixture using the same.

  Conventionally, fluorescent lamps have been the mainstream as a light source for illumination, and lighting fixtures that perform high-frequency lighting using an inverter lighting device are widely used. The inverter lighting device generally includes a series circuit of two switching elements connected to an output terminal of a DC power supply, and a resonance circuit including a fluorescent lamp connected in parallel to one switching element. The two switching elements are alternately turned on and off in response to a drive signal output from the drive circuit, and supply high-frequency AC power generated by the resonance action of the resonance circuit to the fluorescent lamp. As a widely known problem, the switching impedance of the resonant inductor, the resonant capacitor, and the discharge lamp is optimized at the frequency at which the switching operation is performed so that the switching current becomes a slow phase operation when the switching element is turned on and off. Consideration is given to prevent excessive stress from being applied.

  On the other hand, in recent years, light-emitting diodes have attracted attention as electrical light sources other than discharge lamps typified by fluorescent lamps. The light-emitting diode is superior to the fluorescent lamp particularly in terms of life, and the efficiency exceeding that of the fluorescent lamp is expected due to future technological improvements. However, unlike a discharge lamp, a light emitting diode is lit by a lighting circuit that outputs DC power, so a conventional inverter lighting device cannot be used as it is, and a dedicated DC power source that matches the characteristics of the light emitting diode is required. And

JP 2009-272088 A JP 2009-87588 A JP 2003-264090 A

  At present, the luminous efficiency of lighting fixtures using light emitting diodes is becoming almost equivalent to that of fluorescent lighting fixtures, but since the light emitting diodes themselves are quite expensive, FLR 40, 2 which are the mainstream of conventional fluorescent lamps, If it is going to emit the light substantially equivalent to the fixture for lamps, it will be necessary to use about 50-100 light emitting diodes, and a lighting fixture will become very expensive.

  Therefore, a light-emitting diode illuminating device that can be attached to a lighting device or a lighting device for a fluorescent lamp has been proposed so that a user of the lighting device can arbitrarily select a fluorescent lamp and a light-emitting diode.

  As disclosed in Patent Document 1, lighting fixtures using conventional fluorescent lamps are roughly classified into a starter type, a rapid start type, and an inverter type, and even if they are the same type, they are output from a ballast. The voltage and current that can be used vary slightly from manufacturer to manufacturer. Further, in the inverter type lighting circuit, the operating frequency is set to a completely different value in a range exceeding 40 kHz depending on the manufacturer, and the protection function for the discharge lamp disconnection and the lamp life is also completely different. Furthermore, in the inverter type lighting circuit, the stress of the switching element is reduced by matching the impedance of the resonance inductor, the resonance capacitor, and the discharge lamp at the frequency operating as described above. If a light emitting diode having an impedance completely different from the impedance of the discharge lamp is connected to the circuit, there is a high risk of damage to the light emitting diode or lighting circuit. Further, by connecting the light emitting diode, the protection function of the inverter type lighting circuit does not operate normally, which may cause an unsafe situation.

  As for the combination with a copper-iron type ballast, the copper-iron type ballast itself has a simple configuration in which a conductive winding is wound around an iron core that passes magnetism, so the energy stored in the inductor according to the external surge voltage can be reduced. There is a risk of overheating when the insulation deteriorates due to generation of excessive stress applied to the load side or deterioration over time due to use over 10 years. In combination with the light emitting diode, if the light emitting diode is accidentally short-circuited and the current supply becomes excessive, an excessive current may flow through the copper-iron ballast. A combination of a copper-iron ballast having such a simple structure and a light-emitting diode having a long lifetime is considered to be undesirable.

  An object of the present invention is to provide a lighting device and a lighting fixture that allow a user of the lighting fixture to arbitrarily select a fluorescent lamp and a direct current lighting source typified by a light-emitting diode and can be used safely.

  In order to solve the above-described problem, the invention of claim 1 includes the first and second switching elements Q1, Q2 connected between the output terminals of the DC power supply circuit 1, as shown in FIGS. Any of the series circuit, the first control means 11 for outputting a drive signal for periodically turning on and off the first and second switching elements Q1, Q2, and any of the first and second switching elements Q1, Q2 A resonance circuit (resonance unit 4 and preheating unit 3) that is connected in parallel to one of them, preheats the filament of the discharge lamp La, generates a high voltage for starting the discharge lamp La, and supplies high-frequency power during lighting; In the lighting device provided with connection terminals (terminals a and b of the connector CON1 and terminals c and d of the connector CON2) for electrically connecting the discharge lamp La to the resonance circuit, between the output terminals of the DC power supply circuit 1 Close to A voltage conversion circuit (DC / DC conversion unit 5) configured to include the third switching element Q3 and step down the output voltage output from the DC power supply circuit 1 to a necessary voltage; and And an inductor having secondary windings n2 and n3 for supplying a preheating current to the filament. (The preheating transformer T1 or the inductor L1 in FIGS. 6, 7 and 10), and the voltage at the output terminal of at least one of the secondary windings n2 and n3 (secondary winding n2) of the inductor. A rectifier DB for rectification is provided, and an output path of the voltage conversion circuit (DC / DC conversion unit 5) and an output path of the rectifier DB are connected in parallel.

  According to a second aspect of the present invention, in the lighting device according to the first aspect, a load (discharge lamp La or LED module 7) connected to the connection terminals (terminals a and b of the connector CON1 and terminals c and d of the connector CON2). Load discriminating means (the load discriminating section 15 including the resistors R1 to R3 in FIG. 10), and the operation of the first control means 11 or the second control means 12 according to the discrimination result of the load discriminating means. A switching means 13 for switching the state is provided.

  Invention of Claim 3 has the lighting device in any one of Claim 1 or 2, and the nozzle | cap | die part which can connect said discharge lamp La, and discharge lamp La or DC lighting which can be connected to said nozzle | cap | die part It is the lighting fixture characterized by including the light source module 7 which has an electrical light source to perform (FIG. 3, FIG. 4, FIG. 5).

  According to the first aspect of the present invention, the first and second switching elements are driven by the first control means so that the discharge lamp can be turned on at a high frequency, and the second control means allows the third voltage conversion circuit to be turned on. By driving the switching element, a light source such as an LED can be lit in direct current.

  According to the second aspect of the present invention, by selecting the operation of the first control means and the second control means by the load determination means, it is possible to selectively light a light source that is lit in direct current, such as a discharge lamp or an LED.

  According to invention of Claim 3, the lighting fixture which can light either the discharge lamp which carries out high frequency lighting, such as a fluorescent lamp, or the light source which carries out DC lighting, such as LED, can be provided.

It is a circuit diagram at the time of connecting a discharge lamp to the lighting device of Embodiment 1 of this invention. It is a circuit diagram at the time of connecting an LED module to the lighting device of Embodiment 1 of this invention. It is a front view which shows the external appearance of the lighting device of Embodiment 1 of this invention. It is a perspective view which shows the external appearance of the lighting fixture carrying the lighting device of Embodiment 1 of this invention. It is the perspective view which saw through and showed the light emission part of the LED module which can be connected to Embodiment 1 of this invention. It is a circuit diagram at the time of connecting a discharge lamp to the lighting device of Embodiment 2 of this invention. It is a circuit diagram at the time of connecting a discharge lamp to the lighting device of Embodiment 3 of this invention. It is an operation | movement waveform diagram at the time of the discharge lamp connection of Embodiment 3 of this invention. It is an operation | movement waveform diagram at the time of LED module connection of Embodiment 3 of this invention. It is a circuit diagram at the time of connecting a discharge lamp to the lighting device of Embodiment 4 of this invention. It is a circuit diagram of the LED module used for the lighting device of Embodiment 4 of this invention. It is a characteristic view of the LED module used for the lighting device of Embodiment 4 of this invention.

(Embodiment 1)
1 and 2 are circuit diagrams of Embodiment 1 of the present invention. FIG. 1 shows a case where a discharge lamp is connected, and FIG. 2 shows a case where an LED module is connected.
The DC power supply unit 1 outputs, for example, a DC voltage obtained by rectifying and smoothing a commercial AC power supply using a full-wave rectifier and a boost chopper circuit. The high-frequency conversion unit 2 is configured by connecting a circuit in which switching elements Q1 and Q2 such as MOSFETs are connected in series between output terminals of the DC power supply unit 1. The switching elements Q1 and Q2 are alternately turned on and off by the inverter drive unit 11.

  After a predetermined DC voltage is started to be supplied from the DC power supply unit 1, the control power supply unit 6 generates the control power supply voltage Vcc and supplies the control power supply voltage Vcc to the inverter drive unit 11 and the DC / DC conversion drive unit 12. The The inverter drive unit 11 and the DC / DC conversion drive unit 12 receive the operation selection signal output from the operation switching unit 13 and determine their operation states. The detailed operation of the operation switching unit 13 will be described later.

  The inverter drive unit 11 is, for example, an integrated circuit. When the operation is started in response to the operation selection signal from the operation switching unit 13, the switching elements Q1 and 1 of the high-frequency conversion unit 2 are output from the Hout terminal and the Lout terminal as output terminals. A drive signal is output to Q2. In parallel with one switching element Q2, a resonance unit 4 including a DC cut capacitor C2, a resonance inductor L1, and a resonance capacitor C1 is connected. Further, in parallel with the resonance unit 4, a preheating transformer T1 having secondary windings n2 and n3, a capacitor C3 connected in series to the primary winding, and a rectifier DB connected to one secondary winding n2. The preheating part 3 comprised is connected.

  Further, a connector that can be electrically connected to the outside of the lighting device so that the discharge lamp La is connected in parallel to the resonance capacitor C1 of the resonance unit 4 and the preheating current is supplied from the preheating unit 3 to the filament of the discharge lamp La. CON1 and CON2 are provided.

  When the discharge lamp La is connected to the connectors CON1 and CON2 and the operation of the inverter driving unit 11 is started in response to the operation selection signal output from the operation switching unit 13, the frequency of the driving signal is changed as is generally known. Each control of the pre-heating, starting, and lighting by performing is performed.

  The drive signal generation of the switching element Q1 uses the voltage charged in the capacitor C6 as a power source. High frequency power is generated in the secondary windings n2 and n3 of the preheating transformer T1 by the high frequency generated when the switching elements Q1 and Q2 are alternately turned on and off. Here, the rectifier DB is connected to the output terminal of the secondary winding n2 of the preheating unit 3. The high frequency power generated in the secondary winding n2 of the preheating transformer T1 is rectified to direct current by the full wave rectifier DB, and the filament of the discharge lamp La connected to the connector CON2 (terminals c and d) is preheated with direct current power. It will be.

  On the other hand, a DC / DC conversion unit 5 including a switching element Q3, diodes D1 and D2, an inductor L2, and a capacitor C4 is connected to the output terminal of the DC power supply unit 1. The configuration of the DC / DC converter 5 is the same as that of a generally known step-down chopper circuit, and details thereof are omitted. The switching element Q3 is driven by the output of the DC / DC conversion driving unit 12. Similarly, the DC / DC conversion drive unit 12 is also integrated, and outputs a drive signal from the output terminal Hout terminal to the switching element Q3 to set the ON time width of the switching element Q3 to a desired value. As a result, the DC voltage generated in the capacitor C4 at the output end can be controlled.

  In the case of the configuration of FIG. 1, since the discharge lamps La are connected to the connectors CON1 and CON2, DC / DC conversion is performed in accordance with an operation selection signal output from the operation switching unit 13 to the DC / DC conversion driving unit 12. Part 5 is assumed to be stopped.

  Although the output terminal of the DC / DC converter 5 is connected to the output terminal of the rectifier DB via the diode D2, the voltage generated in the capacitor C4 because the DC / DC converter 5 is stopped, that is, the diode D2 The anode side potential of the discharge lamp La is 0 [V], and the filament on the terminal cd side of the discharge lamp La is preheated by the output of the rectifier DB connected to the output terminal of the secondary winding n2 of the preheating unit 3. Become.

  Next, FIG. 2 shows a case where the LED module 7 composed of a plurality of LEDs is connected to the connector CON2. As shown in the figure, the cathode side of the LED module 7 is connected to the connection terminal c of the connector CON2, and the anode side is connected to the connection terminal d of the connector CON2.

  The inverter driving unit 11 stops in response to the operation selection signal output from the operation switching unit 13 and the DC / DC conversion driving unit 12 starts to operate. Therefore, a diode is connected from the output end (capacitor C4) of the DC / DC conversion unit 5 to the diode. Direct current power is supplied to the LED module 7 via D2. Here, the inverter drive unit 11 is stopped, and the voltage of the secondary winding n2 of the preheating unit 3 becomes 0 [V], so that appropriate DC power is supplied from the output end of the DC / DC conversion unit 5. Will be.

  The lighting device of the present invention is configured by mounting the electronic component shown in FIG. 1 on at least one printed circuit board and housing the mounting board in a case 20 as shown in FIG. The connectors CON1 and CON2 are arranged so as to be connectable to the discharge lamp La or the LED module 7 outside the lighting device. CON3 is a connector on the power source side, and wiring for supplying commercial AC power to the DC power source unit 1 is connected. The case 20 is provided with screw holes 21 for fixing at both ends.

  The lighting device covered with such a case outline is built in the fixture body 31 of the lighting fixture 30 as shown in FIG. The connectors CON1 and CON2 of the lighting device are respectively connected to the socket part 32 to which the base part of the discharge lamp La can be connected and inserted.

  The LED module 7 may be configured as shown in FIG. 5 so that it can be connected to and inserted into such a luminaire, and a plurality of LEDs are mounted on a substrate and have substantially the same shape as a discharge lamp. The terminals a, b, c, and d having the same shape as the cap portion of the discharge lamp La may be provided within a casing having translucency.

  The detailed operation of the operation switching unit 13 may be any as long as the above operation can be realized. For example, the operation switching unit 13 is configured by a microcomputer, and although not shown, a light source selection signal by a setting switch or the like is input, and binary signals of “H” and “L” are input to the inverter driving unit 11 accordingly. The inverter driving unit 11 and the DC / DC conversion driving unit 12 are configured to operate when an “H” signal is input and to stop when an “L” signal is input. It ’s fine.

  The preheating unit 3 is not limited to the configuration in which the preheating transformer T1 and the capacitor C3 are connected in series. For example, a switching element is connected in series with the preheating transformer T1, and the switching element is turned on at least during the preceding preheating, and is turned off at the time of lighting. You may control to.

  As described above, by using the lighting device of the present invention, the discharge lamp and the LED module can be freely used without increasing the number of connection terminals and sockets of the lighting device required for the lighting device for the discharge lamp. The lighting fixture can be assembled at low cost using the manufacturing equipment for the lighting fixture for the discharge lamp.

  Furthermore, the terminals a and b and the c and d sides of the LED module 7 shown in the present embodiment are electrically insulated, and there is no possibility of causing an unsafe phenomenon even when attached to a conventional lighting fixture.

(Embodiment 2)
FIG. 6 is a circuit diagram of Embodiment 2 of the present invention. Here, the configuration when the discharge lamp La is connected is shown. In the first embodiment, the high-frequency power generated in the secondary winding n2 of the preheating transformer T1 is rectified to direct current by the rectifier DB to preheat the filament of the discharge lamp La. However, in this embodiment, the resonance inductor of the resonance unit 4 is used. A secondary winding n2 is provided in L1, and the high-frequency power generated in the secondary winding n2 is similarly rectified to direct current by the rectifier DB to preheat the filament of the discharge lamp La. In addition, as shown in the figure, a capacitor is connected between the secondary windings n2 and n3 and the filament to prevent the secondary windings n2 and n3 from being short-circuited due to filament abnormality of the discharge lamp La. It is good also as composition to do.

  The configuration of the DC / DC conversion unit 5 is also a step-down chopper configuration as in the first embodiment, and is connected from the output end of the DC / DC conversion unit 5 to the output end (terminal d side) of the rectifier DB via the diode D2. The

  In this example, since the preheating part is simplified, the lighting device can be configured at low cost by reducing the number of parts.

(Embodiment 3)
FIG. 7 is a circuit diagram of Embodiment 3 of the present invention. Here, the configuration when the discharge lamp La is connected is shown. In the present embodiment, the filament preheating of the discharge lamp La supplies the preheating power by providing the secondary winding n2 in the resonance inductor L1 as in the second embodiment. Further, the resonance capacitor C1 is connected between the connection terminals b-d so as to be connected via the filament of the discharge lamp La, and current is not supplied to the resonance unit 4 when the discharge lamp La is removed. It is configured.

  The basic configuration of the DC / DC conversion unit 5 is a step-down chopper configuration configured with switching elements and the like as in the first and second embodiments. However, the switching elements constituting the DC / DC conversion unit 5 are replaced with the high-frequency conversion unit 2. The number of parts is reduced by sharing the switching element Q1. The output terminal of the DC / DC converter 5 is connected to the output terminal (terminal d side) of the rectifier DB via the switching element Q4.

  The operation switching unit 13 outputs an operation selection signal to the drive control unit 14 having a function capable of switching between a drive signal for alternately turning on and off the switching elements Q1 and Q2 and a drive signal for turning on and off only the switching element Q1. The drive signal is output to the switching element Q4 connected to the output terminal of the DC / DC converter 5.

  Detailed operations of the operation switching unit 13 and the drive control unit 14 in the present embodiment are shown in the timing charts of FIGS. FIG. 8 shows the operation when the discharge lamp La is connected. When the discharge lamp La is connected, an operation selection signal output from a load determination unit (not shown) (see FIG. 10) to the operation switching unit 13 is based on a predetermined threshold value Vref2 as shown in FIG. It shall be a low voltage. At this time, the drive signals Hout and Lout output from the drive control unit 14 to the switching elements Q1 and Q2 have a pause period t1 when the drive signal rises and falls as shown in FIGS. The switching current flowing through the switching elements Q1 and Q2 becomes a signal having a period To, and has a delayed waveform as shown in FIGS. In order to perform pre-heating, starting, and lighting control of the discharge lamp La, the drive control unit 14 is configured to perform frequency control in which the period To of the drive signals Hout and Lout is varied and the pause period t1 is kept constant. Good.

  Further, a signal of approximately 0 [V] is output from the operation switching unit 13 to the switching element Q4 connected to the output terminal of the DC / DC conversion unit 5, as shown in FIG. Turn off. When the switching element Q1 is turned on / off, a voltage is generated at the output terminal (capacitor C4) of the DC / DC converter 5, but since the switching element Q4 is turned off, DC power is not supplied to the connection terminal d of the connector CON2. The filament of the discharge lamp La connected between the terminals cd is preheated by the DC power output from the rectifier DB.

  Next, the operation when the LED module 7 is connected is shown in FIG. The operation selection signal in this case is assumed to be a voltage lower than the threshold value Vref1 and higher than the threshold value Vref2 as shown in FIG.

  At this time, the drive signals Hout and Lout output from the drive control unit 14 to the switching elements Q1 and Q2 are as shown in FIGS. 5B and 5C, and the drive signal Lout maintains 0 [V]. The drive signal Hout is repeatedly turned on and off at a cycle T2. Therefore, the switching currents flowing through the switching elements Q1 and Q2 are as shown in FIGS. 4D and 4E, and a sawtooth wave current waveform is obtained because energy is stored in the inductor L2 when the switching element Q1 is on. When the switching element Q1 is off, the energy of the inductor L2 is released, and this emission current flows through a diode parasitic in antiparallel to the switching element Q2. That is, the switching element Q1 functions as a switching element of the step-down chopper circuit, and the antiparallel diode of the switching element Q2 functions as a diode for energizing a regenerative current of the step-down chopper circuit. In order to realize the step-down chopper control for adjusting the voltage of the capacitor C4, the drive control unit 14 may be configured to perform duty control that varies at least one of the ON period of the switching element Q1 or the ON / OFF cycle T2.

  Further, at this time, since the “H” signal is output from the operation switching unit 13 to the switching element Q4 connected to the output terminal of the DC / DC conversion unit 5, as shown in FIG. The DC power generated at the output end of the DC / DC converter 5 is supplied to the terminal d of the connector CON2. The drive control unit 14 may have any configuration as long as it selects either one of the frequency control and the duty control according to the operation selection signal as described above.

  In addition, when the LED module 7 is connected, the drive signal Lout is maintained at 0 [V]. However, the charging voltage of the capacitor C6 serving as a power source for generating the drive signal of the switching element Q1 is stably secured. Therefore, the drive signal Lout may be set to “H” during the period when the drive signal Hout is “L”.

  As a more specific example of duty control, the source voltage of the switching element Q1 is detected, or the inductor L2 is provided with a secondary winding, and the secondary winding voltage is detected to thereby release the energy of the inductor L2. Since it is sometimes possible to determine that the current becomes approximately 0 [A], the drive control unit 14 includes a control unit that turns on the switching element Q1 at the timing when the current of the inductor L2 is determined to be 0 [A]. May be provided.

  In the present embodiment, the switching elements constituting the DC / DC converter 5 and the switching elements constituting the high-frequency converter 2 can be shared, and a control circuit for outputting a drive signal to these switching elements can also be shared. Therefore, the number of parts can be greatly reduced by integrating the drive control unit 14 into an integrated circuit.

(Embodiment 4)
FIG. 10 is a circuit diagram of Embodiment 4 of the present invention. Here, the configuration when the discharge lamp La is connected is shown. Although the configuration is almost the same as that of the second embodiment, a load determination unit 15 is added to detect whether the load connected to the connector CON2 is the discharge lamp La or the LED module 7 shown in FIG. The operation switching unit 13 determines the operation state in accordance with the determination signal output from the unit 15.

  In the voltage-current characteristics of the LED module 7 shown in FIG. 11A, a predetermined threshold value Vth exists as in a normal diode as shown in FIG. For example, as shown in the figure, the load determination unit 15 is configured to connect a plurality of resistors R1, R2, and R3 in series, and the voltage generated at the connection point of the resistors R1 and R2 is set to the threshold of the LED module 7 described above. A voltage higher than the value voltage Vth is set.

  When the LED module 7 is connected between the connection terminals dc of the connector CON2, a minute current flows through the LED module 7, and is determined by the equivalent impedance of the LED module 7 and the resistors R1, R2, and R3 at this time. A determination signal is generated at the connection point between the resistors R2 and R3 (see FIG. 9A).

  When the discharge lamp La is connected, the filament of the discharge lamp La is connected between the connection terminals dc of the connector CON2. Since the equivalent impedance of the filament of the discharge lamp La is around 10 [Ω], the voltage generated at the connection point between the resistors R1 and R2 is substantially equal to 0 [V], and the determination generated at the connection point between the resistors R2 and R3. The signal is also substantially 0 [V] (see FIG. 8A).

  When neither the discharge lamp La nor the LED module 7 is connected, the determination signal is a voltage determined by the resistors R1, R2, and R3 (a voltage higher than Vref1 in FIGS. 8 and 9).

  By performing the load determination by the method as described above, as described in the second embodiment, a predetermined operation can be performed when the discharge lamp is connected or when the LED module is connected, and both the discharge lamp and the LED module are connected. If not, the operation of the lighting device can be stopped. Therefore, even after installing the lighting fixture, the user can freely select and use the discharge lamp and the LED module.

  There are variations in the voltage-current characteristics of the LED chips, and the LED module 7 has a plurality of LED chips. Therefore, there are cases where light is emitted or not emitted when a minute current is passed. If a high resistance is connected in parallel with the series circuit of LED chips as shown in B), it becomes possible to determine the load without considering the light emission variation.

  In this embodiment, the circuit configuration is almost the same as that of the second embodiment, but the same effect can be realized even with the circuit configuration of the first or third embodiment.

  In the first to fourth embodiments, a light emitting diode is representatively described as a light source that is lit in direct current, but may be an organic EL.

DESCRIPTION OF SYMBOLS 1 DC power supply part 2 High frequency conversion part 3 Preheating part 4 Resonance part 5 DC / DC conversion part 7 LED module 11 Inverter drive part (1st control means)
12 DC / DC conversion drive unit (second control means)
13 Operation switching part T1 Preheating transformer n2 Secondary winding La Discharge lamp Q1-Q3 Switching element CON1, CON2 Connector

Claims (3)

A first circuit for outputting a drive signal for alternately turning on and off the first and second switching elements periodically and a series circuit of the first and second switching elements connected between the output terminals of the DC power supply circuit And a resonance connected to one of the first and second switching elements in parallel, to preheat the filament of the discharge lamp, to generate a high voltage for starting the discharge lamp, and to supply high frequency power during lighting In a lighting device comprising a circuit and a connection terminal for electrically connecting a discharge lamp to the resonance circuit, the lighting device includes a third switching element connected between output terminals of the DC power supply circuit. A voltage conversion circuit that steps down the output voltage output from the power supply circuit to a required voltage, and a drive signal for turning on / off the third switching element of the voltage conversion circuit. Control means, and the resonance circuit includes an inductor having a secondary winding for supplying a preheating current to the filament, and the voltage of at least one output terminal of the secondary winding of the inductor is set. A lighting device comprising a rectifier for rectification, wherein an output path of the voltage conversion circuit and an output path of the rectifier are connected in parallel. Load determining means for determining the load connected to the connection terminal, and switching means for switching the operating state of the first control means or the second control means according to the determination result of the load determining means. The lighting device according to claim 1. A light source module comprising: the lighting device according to claim 1; and a base part to which the discharge lamp can be connected, and a discharge lamp that can be connected to the base part or an electric light source that performs direct current lighting. A lighting apparatus comprising:

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