JP2006185604A - Discharge lamp lighting device and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of turning on/off respective discharge lamps intermittently or separately, and to provide a luminaire. <P>SOLUTION: This discharge lamp lighting device 1 has an inverter circuit 4 which is provided with a first switch element FET2, a plurality of second switch elements FET3 and FET4 connected to the first switch element FET2, load circuits 5 and 6 connected between both ends of the second switch elements FET3 and FET4, a plurality of break circuits D2 and D4 connected between the first and second switch elements FET2, FET3, and FET4, and discharge circuits D3 and D5 connected in parallel to a series circuit including the first switch element FET2 and the break circuits D2 and D4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a discharge lamp lighting device and a lighting fixture for lighting a plurality of discharge lamps.

  This type of discharge lamp lighting device is known in which a discharge lamp is connected to each lighting circuit (see, for example, Patent Document 1). This prior art discharge lamp device has a brightness of the discharge lamp. Although it is controlled so as to be substantially constant, since the individual lighting circuits are individually controlled by the control unit, the discharge lamps connected to each lighting circuit can be individually turned on and off.

  Also, a load circuit including a plurality of discharge lamps connected in parallel between the outputs of an inverter circuit has been proposed (see, for example, Patent Document 2). In this conventional discharge lamp lighting device, a plurality of discharge lamps are dimmed by changing the lamp current by changing the oscillation frequency of the inverter circuit.

In addition, a load circuit including a discharge lamp connected in parallel to each switching means of the inverter circuit has been proposed (see, for example, Patent Document 3). This prior art discharge lamp lighting device is configured to be able to thin out the discharge lamp of one load circuit.
Japanese Patent Laid-Open No. 11-191495 (page 3, FIG. 1) Japanese Patent Laid-Open No. 10-79299 (page 4, FIG. 1) Japanese Unexamined Patent Publication No. 2000-102263 (page 6, FIG. 1)

  The discharge lamp lighting device of Patent Document 1 has the disadvantages that the individual lighting circuits individually control the discharge lamp, so that the number of components increases, making it difficult to reduce the size and increasing the cost.

  The discharge lamp lighting device of Patent Document 2 has a plurality of discharge lamps attached to one inverter circuit. Since the resonance circuit is shut off simultaneously with the removal of the discharge lamp, thinning is possible. Cannot be lit.

  Further, in the configuration of the discharge lamp lighting device of Patent Document 3, the resonance circuit is independent, and a high voltage is output when the discharge lamp is removed, stressing the components, which is dangerous for the user. .

  It is an object of the present invention to provide a discharge lamp lighting device and a lighting fixture that can reduce the number of parts and can thin out or individually turn on and off individual discharge lamps.

  The invention of the discharge lamp lighting device according to claim 1 is a DC voltage source that outputs a DC voltage; a first switch element; a plurality of second switch elements connected to the first switch element; Parallel to a load circuit connected between both ends of the two switch elements, a plurality of cutoff circuits connected between the first and second switch elements, and a series circuit including the first switch element and the cutoff circuit An inverter circuit that outputs a high-frequency voltage by alternately switching on and off the first and second switch elements connected in series between the outputs of the DC voltage source. And an inverter circuit control means for controlling the on / off frequency of the first and second switch elements, wherein the shut-off circuit receives a current supplied from a DC voltage source when the first switch element is on. The load circuit is configured so that the regenerative current of the load circuit does not flow to the other load circuit side when the first switch element is turned off, and the discharge circuit is configured so that the regenerative current of the load circuit is turned off when the second switch element is turned off. It is characterized by being made to discharge | release.

  In the present invention and each of the following inventions, each configuration is as follows unless otherwise specified.

  In the inverter circuit, the first switch element is shared, and an output is formed between both ends of the plurality of second switch elements connected in parallel. That is, the output of the inverter circuit is formed by the number of the second switch elements.

  A plurality of load circuits can be connected between both ends of the second switch element.

  The cutoff circuit prevents the regenerative current of the load circuit connected between both ends of the second switch element to which the cutoff circuit is connected from flowing to the first switch element side. The regenerative current flows through the discharge circuit and is regenerated in a closed circuit formed by a DC voltage source, an inverter circuit, and a load circuit. That is, the cutoff circuit individually forms the output of the inverter circuit.

  The inverter circuit control means may control the on / off frequencies of the first and second switch elements to be constant so that, for example, the discharge lamps of the load circuit are all lit, and the dimming lighting is performed by changing the on / off frequencies. You may make it make it.

  According to the present invention, the interruption circuit prevents the regenerative current of the load circuit from flowing to the other load circuit side, and the discharge circuit discharges the regenerative current of the load circuit, so that it is serially connected to the first switch element. A multi-lamp discharge lamp lighting device is configured according to the number of connected second switch elements. And since the 1st switch element is shared in an inverter circuit, the quantity of the 1st switch element with respect to the 2nd switch element to which a load circuit is connected is reduced.

  The invention of the discharge lamp lighting device according to claim 2 is configured such that the on / off operation of the second switch element can be individually stopped according to the external signal in the discharge lamp lighting device according to claim 1. And load circuit control means.

  When the on / off operation of the second switch element is stopped, the resonance current does not flow through the load circuit, and no high-frequency voltage is output between both ends of the second switch element. In addition, since the cutoff circuit is connected to each of the second switch elements, the regenerative current (resonant current) of the load circuit connected to the other second switch element is the second of which the on / off operation is stopped. It does not flow through the load circuit connected to the switch element.

  The input of the external signal may be wired or wireless.

  According to the present invention, when the load circuit control means stops the on / off operation of the second switch element in response to the external signal, no high-frequency voltage is output between both ends of the second switch element, and the second The discharge lamp of the load circuit connected between both ends of the switch element is turned off. Since the load circuit control means is configured to be able to individually stop the on / off operation of the second switch element, all the discharge lamps or desired discharge lamps are extinguished by the external signal.

  A discharge lamp lighting device according to a third aspect of the present invention is the discharge lamp lighting device according to the second aspect, further comprising lamp connection detection means for detecting a connection state of the discharge lamp in the load circuit. The control means stops the on / off operation of the second switch element to which the load circuit is connected in response to a signal when the lamp connection detection means detects the disconnection of the discharge lamp in the load circuit. It is characterized by that.

  “Detecting the connection state of the discharge lamp in the load circuit” means detecting whether or not the discharge lamp is connected to the discharge lamp lighting device, and more specifically, the discharge lamp is a lamp socket of the lighting fixture. This means that it is detected whether or not it is normally attached.

  According to the present invention, for example, when the discharge lamp is removed from the load circuit and thinned, it is detected by the lamp connection detecting means that the discharge lamp is not connected to the load circuit. The load circuit control means stops the on / off operation of the second switch element to which the load circuit is connected. As a result, the high-frequency voltage is not output between both ends of the second switch element, and the discharge lamp of the load circuit is turned off.

  When the discharge lamp is removed from the load circuit, even if the load circuit forms a closed circuit with an inductor, a resonance capacitor, etc., it is blocked by the cutoff circuit and affects other load circuits. Absent.

  A discharge lamp lighting device according to a fourth aspect of the present invention is the discharge lamp lighting device according to any one of the first to third aspects, wherein the direct-current voltage is controlled so as to change the output of the direct-current voltage source in accordance with an external signal. Source control means, and the light output of the discharge lamp of the load circuit changes as the output of the DC voltage source changes according to the external signal.

  According to the present invention, when the output of the DC voltage source is changed in accordance with an external signal input to the DC voltage source control means, the high-frequency voltage between both ends of each second switch element of the inverter circuit changes. Then, the resonance current flowing through each load circuit is changed. Due to the change in the resonance current, the light output of the discharge lamp is changed. That is, the discharge lamp is dimmed.

  A discharge lamp lighting device according to a fifth aspect of the present invention is the discharge lamp lighting device according to any one of the first to fourth aspects, further comprising: a capacity increasing / decreasing circuit that increases / decreases the capacitance of the resonance capacitor. The control means controls the capacity increasing / decreasing circuit to increase / decrease the capacity of the resonance capacitor according to the external signal, and the light output of the discharge lamp of the load circuit changes by increasing / decreasing the capacity of the resonance capacitor. Features.

  The capacity increasing / decreasing circuit is provided for each load circuit, and may be provided in all the load circuits or in some of the load circuits.

  When the capacity of the resonance capacitor increases, the current flowing through the resonance capacitor increases, so that the discharge current of the discharge lamp connected in parallel to the resonance capacitor decreases and the light output decreases. Conversely, when the capacity of the resonance capacitor decreases, the current flowing through the resonance capacitor decreases, the discharge current of the discharge lamp increases, and the light output increases. That is, the discharge lamp is dimmed according to the increase or decrease of the resonance capacitor.

  According to the present invention, when an external signal is input to the inverter circuit control means, the capacity of the resonance capacitor of the load circuit is increased or decreased by the control of the capacity increase / decrease circuit by the inverter circuit control means, and the resonance current flowing through the load circuit is increased. Increasing or decreasing the light output of the discharge lamp.

  The invention of a lighting fixture according to claim 6 comprises the discharge lamp lighting device according to any one of claims 1 to 5; and a lighting fixture body in which the discharge lamp lighting device is disposed. It is characterized by.

  According to the present invention, since the discharge lamp lighting device according to any one of claims 1 to 5 is provided, the individual discharge lamps can be individually controlled or thinned out, or can be dimmed.

  The invention of the lighting device according to claim 7 is the lighting device according to claim 6, wherein at least two of the plurality of load circuits have different color temperatures of the discharge lamp. .

  According to the present invention, since the discharge lamps have different color temperatures, the color temperature of the illumination light emitted from the luminaire is changed by thinning out or dimming the discharge lamps having different color temperatures.

  According to the first aspect of the present invention, a multi-lamp discharge lamp lighting device can be configured according to the number of second switch elements connected in series to the first switch element, and a load circuit Since the first switch element is shared with respect to the second switch element to which is connected, and the number of the first switch elements is reduced, the discharge lamp lighting device can be reduced in size and made inexpensive. Can do.

  According to the invention of claim 2, since the load circuit control means can individually stop the on / off operation of the second switch element in accordance with the external signal, the control for all the discharge lamps can be performed by turning off the desired discharge lamp. Light can be emitted and power can be saved.

  According to the invention of claim 3, when the discharge lamp is not connected to the load circuit, such as thinning out of the discharge lamp, the on / off operation of the second switch element to which the load circuit is connected is stopped. A high voltage is not output to the connection terminal side of the discharge lamp such as a socket, so that electric shock on the connection terminal side can be suppressed and power saving can be achieved.

  According to the invention of claim 4, since the DC voltage source control means changes the output of the DC voltage source circuit in accordance with the external signal, all the discharge lamps are dimmed simultaneously by inputting the external signal. be able to.

  According to the invention of claim 5, since the inverter circuit control means controls the capacity increasing / decreasing circuit to increase / decrease the capacity of the resonance capacitor in accordance with the external signal, the discharge is performed by inputting the external signal. The lamps can be dimmed individually.

  According to the invention of claim 6, since the discharge lamp lighting device according to any one of claims 1 to 5 is provided, a desired discharge lamp is extinguished or thinned by an external signal, or the discharge lamp It is possible to provide a luminaire that can save power by dimming the whole or individually.

  According to the seventh aspect of the present invention, it is possible to produce illumination according to the atmosphere by thinning or dimming the discharge lamps having different color temperatures to change the color temperature of the illumination light emitted from the lighting fixture. .

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, a first embodiment of the present invention will be described.

  1 and 2 show a first embodiment of the present invention. FIG. 1 is a circuit diagram of a discharge lamp lighting device, and FIG. 2 is a circuit diagram of another load circuit.

  In FIG. 1, a discharge lamp lighting device 1 includes a DC voltage source 3 having a DC voltage generation circuit 2A and a chopper circuit 2B, an inverter circuit 4, load circuits 5 and 6, and an inverter circuit as control means for the inverter circuit. The control circuit 7 includes N-type bipolar transistors Tr1 and Tr2 constituting load circuit control means.

  The DC voltage generation circuit 2A includes a rectifier 8 and a filter capacitor C1, converts the AC voltage of the commercial AC power supply Vs into a DC voltage, and outputs the DC voltage between both ends of the capacitor C1. The negative electrode side of the capacitor C1 is connected to the substrate ground E.

  The chopper circuit 2B has a series circuit of an inductor L1 and a field effect transistor FET1 connected between both ends of the capacitor C1, and a series circuit of a diode D1 and a smoothing capacitor C2 connected between both ends of the field effect transistor FET1. Configured. The gate of the field effect transistor FET1 is connected to a chopper circuit control circuit 9 as DC voltage source control means.

  The chopper circuit control circuit 9 turns on and off the field effect transistor FET1 so that a predetermined voltage is generated between both ends of the smoothing capacitor C2. Thus, the chopper circuit 2B boosts the DC voltage output from the DC voltage generation circuit 2A and converts it to a predetermined voltage.

  Thus, the DC voltage source 3 includes the DC voltage generation circuit 2A, the chopper circuit 2B, and the chopper circuit control circuit 9 as the DC voltage source control means, and outputs the DC voltage to the inverter circuit 4 To enter.

  The inverter circuit 4 includes a field effect transistor FET2 as a first switch element, field effect transistors FET3 and FET4 as a second switch element, diodes D2 and D4 as cutoff circuits, diodes D3 and D5 as discharge circuits, and an oscillator 10.

  A first series circuit of a diode D2 and a field effect transistor FET3 connected in parallel via a field effect transistor FET2 between both ends of the smoothing capacitor C2 of the chopper circuit 2B, a diode D4 and a field effect transistor A second series circuit of the FET 4 is connected to each other. The anodes of the diode D2 and the diode D4 are connected to the source of the field effect transistor FET2, and the first series circuit and the second series circuit are connected to be in the forward direction with respect to the field effect transistor FET2. Yes. Thus, the diodes D2 and D4 are connected between the field effect transistor FET2 and the field effect transistors FET3 and FET4, respectively.

  The diode D3 is connected between the field effect transistor FET2 and the diode D2 so as to be in the reverse direction with respect to the field effect transistor FET2, and the diode D5 is field effected so as to be in the reverse direction with respect to the field effect transistor FET2. It is connected between the transistor FET2 and the diode D4. That is, the diodes D3 and D5 are connected in parallel to the respective series circuits of the field effect transistor FET2 and the diodes D2 and D4.

  As will be described later, in the diodes D2 and D4, the current supplied from the smoothing capacitor C2 of the chopper circuit 2B flows when the field effect transistor FET2 is turned on, and the regeneration of the load circuits 5 and 6 is performed when the field effect transistor FET2 is turned off. The current is prevented from flowing into the other load circuits 5 and 6.

  The diode D3 discharges the regenerative current of the load circuit 5 when the field effect transistor FET2 and the field effect transistor FET3 are off, and the diode D4 provides the regenerative current of the load circuit 6 when the field effect transistor FET2 and the field effect transistor FET4 are off. Is to be released.

  The gate and the source of the field effect transistor FET2 as the first switch element are connected to the oscillator 10 via the gate resistor R1. A capacitor C3 is connected between the source of the field effect transistor FET2 and the oscillator 10 as a power source for generating a drive voltage for driving the field effect transistor FET2.

  Further, the gate and source of the field effect transistor FET 3 as the second switch element are connected to the oscillator 10 via a series circuit of the gate resistor R 2 and the buffer 11. Further, the gate and source of the field effect transistor FET4 as the second switch element are connected to the oscillator 10 via a series circuit of the gate resistor R3 and the buffer 12. The series circuit of the gate resistor R2 and the buffer 11 and the series circuit of the gate resistor R3 and the buffer 12 are connected in parallel to each other and connected to the oscillator 10. The buffer 11 and the buffer 12 amplify the current supplied to the respective gates of the field effect transistor FET3 and the field effect transistor FET4.

  Resistance resistors R4, R5, and R6 for protection against surge are connected between the gates and sources of the field effect transistors FET2, FET3, and FET4, respectively. The field effect transistors FET2, FET3, and FET4 include parasitic diodes D6, D7, and D8, respectively, between their drains and sources.

  The oscillator 10 includes gates and sources of the field effect transistor FET2 as the first switch element and the field effect transistors FET3 and FET4 as the second switch element in response to the control signal sent from the inverter circuit integrated circuit 7. A drive voltage is alternately supplied between them. As a result, the field effect transistor FET2 and the field effect transistors FET3 and FET4 are alternately turned on and off. The field effect transistor FET3 and the field effect transistor FET4 are simultaneously turned on / off. By this on / off operation, the DC voltage between both ends of the smoothing capacitor C2 of the chopper circuit 2B is converted into a high-frequency voltage and is output between both ends (drain, source) of the field effect transistor FET3 and the field effect transistor FET4.

  The load circuit 5 includes an inductor L2 connected between the drain and source of the field effect transistor FET3, a DC cut capacitor C4, and a series circuit of the fluorescent lamp 13 as a discharge lamp, and the filament electrodes 13a and 13b of the fluorescent lamp 13. The resonance capacitor C5 is connected to the non-power supply side.

  The load circuit 6 includes a series circuit of an inductor L3 connected between the drain and source of the field effect transistor FET4, a DC cut capacitor C6, and a fluorescent lamp 14 as a discharge lamp, and filament electrodes 14a and 14b of the fluorescent lamp 14. And a resonance capacitor C7 connected to the non-power supply side.

  The load circuit 5 is energized by a high-frequency voltage output between the drain and source of the field effect transistor FET3, and a resonance current flows. That is, when the field effect transistor FET2 is turned on and the field effect transistor FET3 is turned off, the field effect transistor FET2, the diode D2, the inductor L2, the DC cut capacitor C4, and the fluorescent lamp 13 are connected from the positive side of the smoothing capacitor C2 of the chopper circuit 2B. A current flows through a path on the negative electrode side of the filament electrode 13a, the resonance capacitor C5, the filament electrode 13b of the fluorescent lamp 13, and the smoothing capacitor C2. At this time, electromagnetic energy is accumulated in the inductor L2, and electric charges are accumulated in the DC cut capacitor C4 and the resonance capacitor C5.

  When the field effect transistor FET2 is turned off (the field effect transistor FET3 is turned off), the current due to the electromagnetic energy accumulated in the inductor L2 is the inductor L2, the DC cut capacitor C4, the filament electrode 13a, and the resonance capacitor C5. , And flows through the path of the filament electrode 13b, the parasitic diode D7 of the field effect transistor FET3, and the inductor L2, and further accumulates charges in the DC cut capacitor C4 and the resonance capacitor C5.

  Next, when the field effect transistor FET3 is turned on (the field effect transistor FET2 is turned off), the current due to the charges accumulated in the DC cut capacitor C4 and the resonance capacitor C5 is changed to the DC cut capacitor C4, the inductor L2, It flows in the closed circuit of the field effect transistor FET3, the filament electrode 13b, the resonance capacitor C5, and the filament electrode 13a.

  When the field effect transistor FET3 is turned off (the field effect transistor FET2 is turned off), the current due to the charges accumulated in the DC cut capacitor C4 and the resonance capacitor C5 becomes a regenerative current, and is used for the DC cut. It flows through the path of the capacitor C4, the inductor L2, the diode D3, the smoothing capacitor C2, the filament electrode 13b, the resonance capacitor C5, and the filament electrode 13a. As a result, the DC cut capacitor C4 and the resonance capacitor C5 are each discharged.

  Then, the field effect transistor FET2 is turned on and the field effect transistor FET3 is turned off. In this repetition, the current flowing through the load circuit 5 becomes a resonance current and preheats the filament electrodes 13a and 13b of the fluorescent lamp 13. Then, after the filament electrodes 13a and 13b are sufficiently preheated, the voltage due to the electric charge accumulated in the resonance capacitor C5 is applied as a resonance voltage between the filament electrodes 13a and 13b, and the fluorescent lamp 13 is turned on. The resonance current mainly becomes a discharge current between the filament electrodes 13a and 13b of the fluorescent lamp 13, and part of the resonance current flows to the resonance capacitor C5.

  As described above, the load circuit 6 is energized by the high-frequency voltage output between the drain and source of the field effect transistor FET4, and after the filament electrodes 14a and 14b of the fluorescent lamp 14 are preheated by the resonance current, the filament electrode The voltage across the resonance capacitor C7 (resonance voltage) is applied between 14a and 14b, and the fluorescent lamp 14 is turned on. The diode D5 as the second diode causes the regenerative current of the load circuit 6 to flow to the positive side of the smoothing capacitor C2 of the chopper circuit 2B, thereby discharging the DC cut capacitor C6 and the resonance capacitor C7, respectively.

  As described above, the diode D2 (diode D4) as the cutoff circuit supplies the current supplied from the smoothing capacitor C2 of the DC voltage source 3 when the field effect transistor FET2 as the first switch element is turned on to the load circuit 5 ( The regenerative current of the load circuit 5 (load circuit 6) does not flow to the other load circuit 6 (load circuit 5) side when the field effect transistor FET2 is turned off.

  Further, the diode D3 (diode D5) as the discharge circuit supplies the regenerative current of the load circuit 5 (load circuit 6) to the DC voltage source 3 when the field effect transistor FET3 (field effect transistor FET4) as the second switch element is turned off. To the smoothing capacitor C2 side. As a result, the output of the inverter circuit 4 is formed between both ends of the field effect transistors FET3 and 4 connected in series to the field effect transistor FET2 and connected in parallel. The load circuits 5 and 6 respectively connected between both ends do not affect each other.

  The inverter circuit integrated circuit 7 is connected to a light receiver 15 that receives a wireless signal transmitted from, for example, a wireless transmitter. If the wireless signal is a dimming signal that changes the light output of the fluorescent lamps 13 and 14, the oscillator 10 sets the on / off frequencies of the field effect transistor FET2 and the field effect transistors FET3 and FET4 according to the dimming signal. A control signal to be controlled is sent out. The oscillator 10 alternately outputs a drive voltage between the gate and source of the field effect transistor FET2 and the field effect transistors FET3 and FET4 according to the control signal.

  An N-type bipolar transistor Tr1 constituting load circuit control means is connected between the gate and source of the field effect transistor FET3 via the buffer 11 so that the collector is on the gate side and the emitter is on the source side. Yes. Further, an N-type bipolar transistor Tr2 constituting load circuit control means is connected between the gate and source of the field effect transistor FET4 via the buffer 13 so that the collector is on the gate side and the emitter is on the source side. Yes.

  The bases of the N-type bipolar transistor Tr1 and the N-type bipolar transistor Tr2 are connected to the inverter circuit control circuit 7. When the wireless signal received by the light receiver 15 is an external signal that turns off the fluorescent lamp 13 (fluorescent lamp 14), the inverter circuit control circuit 7 is based on the base of the N-type bipolar transistor Tr1 (N-type bipolar transistor Tr2). Supply current. As a result, the N-type bipolar transistor Tr1 (N-type bipolar transistor Tr2) is turned on.

  When the N-type bipolar transistor Tr1 (N-type bipolar transistor Tr2) is turned on, the drive voltage output from the oscillator 10 is applied to the substrate ground E side, and the gate of the field effect transistor FET3 (field effect transistor FET4) Is no longer applied. As a result, the field effect transistor FET3 (field effect transistor FET4) does not operate on and off. In other words, as long as the N-type bipolar transistor Tr1 (N-type bipolar transistor Tr2) is on, the field-effect transistor FET3 (field-effect transistor FET4) remains off.

  When the field effect transistor FET3 (field effect transistor FET4) is in the OFF state, the high frequency voltage is not output between the both ends (between the drain and the source), and the resonance current does not flow to the load circuit 5 (load circuit 6). That is, when the field effect transistor FET3 is turned off and the field effect transistor FET2 is turned on, the field effect transistor FET2, diode D2, inductor L2, DC cut capacitor C4, fluorescent lamp from the positive side of the smoothing capacitor C2 of the chopper circuit 2B. A current flows through a path on the negative electrode side of the filament electrode 13a, the resonance capacitor C5, the filament electrode 13b of the fluorescent lamp 13, and the smoothing capacitor C2. At this time, electromagnetic energy is accumulated in the inductor L2, and electric charges are accumulated in the DC cut capacitor C4 and the resonance capacitor C5.

  When the field effect transistor FET2 is turned off, the inductor L2, the DC cut capacitor C4, the filament electrode 13a, the resonance capacitor C5, and the filament electrode 13b until the electromagnetic energy accumulated in the inductor L2 consumes the electromagnetic energy. Then, the electric current flows through the path of the parasitic diode D7 and the inductor L2 of the field effect transistor FET3, and charges are further accumulated in the DC cut capacitor C4 and the resonance capacitor C5.

  Here, when the field effect transistor FET3 is turned on, a current flows so that the DC cut capacitor C4 and the resonance capacitor C5 are discharged. However, since the field effect transistor FET3 is in the OFF state, the DC cut capacitor C4 and the resonance Each capacitor C5 maintains a state in which charges are accumulated. At this time, the anode and cathode of the diode D3 are substantially at the same potential. Therefore, no resonance current flows through the load circuit 5, and the fluorescent lamp 13 is not lit. In the load circuit 6 as well, when the N-type bipolar transistor Tr2 is turned on and the field effect transistor FET4 is turned off, the resonance current does not flow and the fluorescent lamp 14 is not turned on.

  As described above, the inverter circuit control circuit 7 receives an external signal for turning off the fluorescent lamps 13 and 14 from the light receiver 15, and turns on the N-type bipolar transistors Tr1 and Tr2 in accordance with the external signal to generate an electric field. The on / off operations of the effect transistors FET3 and FET4 can be individually stopped. Thereby, the fluorescent lamps 13 and 14 are individually turned off. The inverter circuit control circuit 7 and the N-type bipolar transistors Tr1 and Tr2 constitute load circuit control means.

  Next, the operation of the first embodiment of the present invention will be described.

  When the light receiver 15 receives a dimming signal that changes the light output of the fluorescent lamps 13 and 14, the inverter circuit integrated circuit 7 sends the field effect transistor FET2 and the field effect transistor FET3 to the oscillator 10 in accordance with the dimming signal. , A control signal for controlling the on / off frequency of the FET 4 is transmitted.

  The oscillator 10 alternately outputs a drive voltage between the gate and source of the field effect transistor FET2 and the field effect transistors FET3 and FET4 according to the control signal. The on / off frequency of the field effect transistor FET2 and the field effect transistors FET3 and FET4 is changed, and the high-frequency voltage output between both ends of the field effect transistor FET3 and the field effect transistor FET4 is changed. As a result, the resonance current flowing through the load circuit 5 and the load circuit 6 changes, and the respective light outputs of the fluorescent lamp 13 and the fluorescent lamp 14 change. That is, the fluorescent lamp 13 and the fluorescent lamp 14 are dimmed and lit at the same dimming rate simultaneously according to the dimming signal.

  In order to turn off the fluorescent lamp 13, an external signal (wireless signal) for turning off the fluorescent lamp 13 is transmitted from the wireless transmitter to the light receiver 15, for example. The external signal is input from the light receiver 15 to the inverter circuit control circuit 7. The inverter circuit control circuit 7 turns on the N-type bipolar transistor Tr1. As a result, the drive voltage from the oscillator 10 is not supplied between the gate and source of the field effect transistor FET3, and the on / off operation of the field effect transistor FET3 is stopped. Then, no resonance current flows through the load circuit 5, and the fluorescent lamp 13 is turned off.

  In order to turn off the fluorescent lamp 14, an external signal for turning off the fluorescent lamp 14 is input to the inverter circuit control circuit 7. The inverter circuit control circuit 7 turns on the N-type bipolar transistor Tr2. As a result, the drive voltage from the oscillator 10 is not supplied between the gate and source of the field effect transistor FET4, and the on / off operation of the field effect transistor FET4 is stopped. Then, the resonance current does not flow in the load circuit 6, and the fluorescent lamp 14 is turned off. Thus, the fluorescent lamp 13 and the fluorescent lamp 14 are turned off individually.

  In the discharge lamp lighting device 1, power saving can be achieved by turning off the fluorescent lamp 13 and the fluorescent lamp 14 individually or adjusting the light.

  Since the field effect transistor FET2 as the first switch element is shared with the field effect transistors FET3 and FET4 as the second switch elements in which the outputs of the inverter circuit 4 are respectively formed, the field effect transistor The number of field effect transistors FET2 with respect to FET3 and FET4 is reduced. Therefore, the field effect transistor FET2 to be reduced on the circuit board and the heat dissipating parts for radiating the heat of the field effect transistor FET2 are not mounted, so that the circuit board is miniaturized and the discharge lamp lighting device 1 is miniaturized and inexpensive. Manufactured.

  The discharge lamp lighting device 1 shows two lamps, a fluorescent lamp 13 and a fluorescent lamp 14. Here, in parallel with the series circuit of the diode D2 as the cutoff circuit and the field effect transistor FET3 as the second switch element, the series circuit of the cutoff circuit and the second switch element are sequentially connected, and the second circuit By forming a load circuit between the both ends of the switch element, a multi-lamp discharge lamp lighting device is configured.

  Furthermore, each load circuit may include a plurality of discharge lamps, and a plurality of load circuits may be connected between both ends of the second switch element. FIG. 2 shows an example. The load circuit 5A shown in FIG. 2A is configured by connecting individual load circuits each having fluorescent lamps 13A and 13B in parallel between both ends of a field effect transistor FET3 as a second switch element. Yes. Further, the load circuit 5B shown in FIG. 2B is configured by connecting two discharge lamps 13A and 13B via a balancer L2C.

  Further, in the discharge lamp lighting device 1, the cutoff circuit is constituted by the diodes D2 and D4, but is not limited thereto, and is connected between the field effect transistor FET2 and the field effect transistors FET3 and FET4, respectively. The current supplied from the DC voltage source 3 is supplied to the load circuits 5 and 6 when turned on so that the regenerative current of the load circuits 5 and 6 does not flow to the other load circuits 5 and 6 when the field effect transistor FET2 is turned off. It only has to be configured. The discharge circuit is configured such that the field effect transistor FET2 and the cutoff circuit are connected in parallel to a series circuit, and the regenerative currents of the load circuits 5 and 6 are discharged when the field effect transistors FET3 and FET4 are turned off. Just do it.

  Next, a second embodiment of the present invention will be described.

  FIG. 3 is a circuit diagram of a discharge lamp lighting device showing a second embodiment of the present invention. Note that the same parts as those in FIG.

  A discharge lamp lighting device 16 shown in FIG. 3 has a capacitor C8 as a constant voltage source connected between the oscillator 10 and the substrate ground E in the discharge lamp lighting device 1 shown in FIG. A driving circuit 17 and a driving circuit 18 are connected to the capacitor C8 in parallel. Further, lamp connection detection circuits 19 and 20 are provided as lamp connection detection means for detecting the connection state of the fluorescent lamps 13 and 14 in the respective load circuits 5 and 6.

  The drive circuit 17 includes an N-type bipolar transistor Tr3, a P-type bipolar transistor Tr4, and a resistor R7. A series circuit of an N-type bipolar transistor Tr3 and a P-type bipolar transistor Tr4 is connected between both ends of the capacitor C8. The bases of the N-type bipolar transistor Tr3 and the P-type bipolar transistor Tr4 are connected to the oscillator 10 via the resistor R2, and the emitter of the N-type bipolar transistor Tr3 and the emitter of the P-type bipolar transistor Tr4 are both connected via the resistor R7. Are connected to the gate of a field effect transistor FET3 as a second switch element.

  When the driving circuit 17 outputs a high signal as a driving voltage from the oscillator 10, the high signal is applied to the bases of the N-type bipolar transistor Tr3 and the P-type bipolar transistor Tr4 via the resistor R2. Then, the N-type bipolar transistor Tr3 is turned on and the P-type bipolar transistor Tr4 is turned off. When the N-type bipolar transistor Tr3 is turned on, the high signal is applied to the gate of the field effect transistor FET3 via the resistor R7. Thereby, the field effect transistor FET3 is turned on.

  When a low signal as a drive voltage is output from the oscillator 10, that is, when no drive voltage is output, the N-type bipolar transistor Tr3 is turned off and the P-type bipolar transistor Tr4 is turned on. When the N-type bipolar transistor Tr4 is turned on, the gate of the field effect transistor FET3 is connected to the substrate ground E via the resistor R7 and the N-type bipolar transistor Tr4. As a result, the electric charge accumulated at the gate of the field effect transistor FET3 is discharged, and the field effect transistor FET3 is turned off.

  As described above, the drive circuit 17 is configured so that the N-type bipolar transistor Tr3 and the P-type bipolar transistor Tr4 are alternately turned on and off in accordance with the drive signal composed of the high signal and the low signal output from the oscillator 10. The FET 3 is turned on / off. The bases of the N-type bipolar transistor Tr3 and the P-type bipolar transistor Tr4 are connected to the collector of the N-type bipolar transistor Tr1 serving as load circuit control means. The emitter of the N-type bipolar transistor Tr 1 is connected to the substrate ground E, and the base is connected to the lamp connection detection circuit 19.

  The drive circuit 18 includes an N-type bipolar transistor Tr5, a P-type bipolar transistor Tr6, and a resistor R8, and is formed in the same manner as the drive circuit 17. That is, the drive circuit 18 turns on the field effect transistor FET4 by alternately turning on and off the N-type bipolar transistor Tr5 and the P-type bipolar transistor Tr6 in accordance with the drive signal composed of the high signal and the low signal output from the oscillator 10. It is configured to operate on and off. The drive circuit 18 receives the drive signal simultaneously with the drive circuit 17. That is, the field effect transistor FET3 and the field effect transistor FET4 as the second switch elements are simultaneously turned on / off.

  The bases of the N-type bipolar transistor Tr5 and the P-type bipolar transistor Tr6 of the drive circuit 18 are connected to the collector of an N-type bipolar transistor Tr2 as load circuit control means. The emitter of the N-type bipolar transistor Tr2 is connected to the substrate ground E, and the base is connected to the lamp connection detection circuit 20.

  The lamp connection detection circuit 19 has a series circuit of a resistor R9, a resistor R10 and a resistor R11 connected between both ends of the smoothing capacitor C2 of the chopper circuit 2B, and a smoothing capacitor C9 connected in parallel to the resistor R11. Configured. Here, the negative electrode side of the smoothing capacitor C2 is connected to the substrate ground E.

  The connection point a1 of the resistors R9 and R10 is connected to the non-power supply side of the filament electrode 13b of the fluorescent lamp 13, and the both ends of the resistor R11 are connected between the base and emitter of the N-type bipolar transistor Tr1. Has been.

  When the fluorescent lamp 13 is connected to the load circuit 5, both ends of the filament electrodes 13a and 13b are connected to a series circuit of a resistor R10 and a resistor R11. Since the voltage between both ends of the filament electrodes 13a and 13b is usually very small as 2-3V, even if the voltage between both ends of the resistor R11 is applied between the base and emitter of the N-type bipolar transistor Tr1, the N-type bipolar transistor Tr1 Do not turn on.

  If the fluorescent lamp 13 is not connected to the load circuit 5, both ends of the smoothing capacitor C2 are connected between both ends of the series circuit of the resistor R9, the resistor R10, and the resistor R11, and the voltage across the smoothing capacitor C2 is The voltage is divided by the resistor R9, the resistor R10, and the resistor R11. Since the voltage across the smoothing capacitor C2 is very large, for example, 450V, the N-type bipolar transistor Tr1 is turned on when the voltage across the resistor R11 is applied between the base and emitter of the N-type bipolar transistor Tr1.

  When the N-type bipolar transistor Tr1 is turned on, the bases of the N-type bipolar transistor Tr3 and the P-type bipolar transistor Tr4 of the drive circuit 17 are connected to the substrate ground E, and the drive signal output from the oscillator 10 is output. A high signal is no longer applied to the base. As a result, the N-type bipolar transistor Tr3 is not turned on, a high signal is not applied to the gate of the field effect transistor FET3, and the field effect transistor FET3 is not turned on / off. Then, no high frequency voltage is output between both ends of the field effect transistor FET3.

  The lamp connection detection circuit 20 includes a series circuit of a resistor R12, a resistor R13, and a resistor R14 connected between both ends of the smoothing capacitor C2, and a smoothing capacitor C10 connected in parallel to the resistor R14. Has been. A connection point a2 between the resistors R12 and R13 is connected to the non-power supply side of the filament electrode 14b of the fluorescent lamp 14, and both ends of the resistor R14 are connected between the base and emitter of the N-type bipolar transistor Tr2. Has been.

  When the fluorescent lamp 14 is connected to the load circuit 6, both ends of the filament electrodes 14a and 14b are connected to a series circuit of a resistor R13 and a resistor R14. Since the voltage between both ends of the filament electrodes 14a and 14b is usually very small as 2-3V, even if the voltage across the resistor R14 is applied between the base and emitter of the N-type bipolar transistor Tr2, the N-type bipolar transistor Tr2 Do not turn on.

  If the fluorescent lamp 14 is not connected to the load circuit 6, both ends of the smoothing capacitor C2 are connected between both ends of the series circuit of the resistor R12, the resistor R13, and the resistor R14, and the voltage across the smoothing capacitor C2 is The voltage is divided by the resistor R12, the resistor R13, and the resistor R14. Since the voltage across the smoothing capacitor C2 is very large, for example, 240V, when the voltage across the resistor R14 is applied between the base and emitter of the N-type bipolar transistor Tr2, the N-type bipolar transistor Tr2 is turned on.

  When the N-type bipolar transistor Tr2 is turned on, the bases of the N-type bipolar transistor Tr5 and the P-type bipolar transistor Tr6 of the drive circuit 18 are connected to the substrate ground E, and the drive signal output from the oscillator 10 is output. A high signal is no longer applied to the base. As a result, the N-type bipolar transistor Tr5 is not turned on, the high signal is not applied to the gate of the field effect transistor FET4, and the field effect transistor FET4 is not turned on / off. Then, no high frequency voltage is output between both ends of the field effect transistor FET4.

  As described above, the N-type bipolar transistor Tr1 is turned on in response to the signal (the voltage across the resistor R11) when the lamp connection detection circuit 19 detects the disconnection of the fluorescent lamp 13 in the load circuit 5. The on / off operation of the effect transistor FET3 is stopped. Further, the N-type bipolar transistor Tr2 is turned on in response to a signal (a voltage across the resistor R14) when the lamp connection detection circuit 20 detects the disconnection of the fluorescent lamp 14 in the load circuit 6, whereby a field effect transistor is turned on. The on / off operation of the FET 4 is stopped.

  The fact that the fluorescent lamp 13 (fluorescent lamp 14) is connected in the load circuit 5 (load circuit 6) means that the fluorescent lamp 13 (fluorescent lamp 14) is normally mounted in the lamp socket of the lighting fixture. You can do it. Further, if the fluorescent lamp 13 (fluorescent lamp 14) is not connected in the load circuit 5 (load circuit 6), the fluorescent lamp 13 (fluorescent lamp 14) is not normally attached to the lamp socket of the lighting fixture. It can be understood that it has been removed from the lamp socket.

  The inverter circuit control circuit 7 receives a dimming signal that changes the light output of the fluorescent lamps 13 and 14 from the light receiver 15, and the field effect transistor FET 2 and the field effect are supplied to the oscillator 10 in accordance with the dimming signal. A control signal for controlling the on / off frequency of the transistors FET3 and FET4 is transmitted.

  Next, the operation of the second exemplary embodiment of the present invention will be described.

  When the fluorescent lamp 13 is removed from the lamp socket and the fluorescent lamp 13 is not connected to the load circuit 5 (the fluorescent lamp 13 is thinned out), the voltage across the resistor R11 of the lamp connection detection circuit 19 rises, and N-type bipolar The transistor Tr1 is turned on. When the N-type bipolar transistor Tr1 is turned on, the drive voltage output from the oscillator 10 is applied to the substrate ground E side and is not input to the drive circuit 17, so the on / off operation of the field effect transistor FET3 is stopped.

  When the fluorescent lamp 14 is removed from the lamp socket and the fluorescent lamp 14 is not connected to the load circuit 6 (the fluorescent lamp 14 is thinned out), the voltage across the resistor R14 of the lamp connection detection circuit 20 rises, and N The bipolar transistor Tr2 is turned on. When the N-type bipolar transistor Tr2 is turned on, the drive voltage output from the oscillator 10 is applied to the substrate ground E side and is not input to the drive circuit 18, so the on / off operation of the field effect transistor FET4 is stopped.

  Thus, when the fluorescent lamp 13 or the fluorescent lamp 14 is removed from the lamp socket and thinned out, the on / off operation of the field effect transistor FET3 or the field effect transistor FET4 is stopped, so that power saving of the discharge lamp lighting device 16 can be achieved.

  When the fluorescent lamp 13 (fluorescent lamp 14) is thinned out, the load circuit 5 (load circuit 6) is opened and does not form a closed circuit, and no resonance current flows. As shown in FIG. 2, the load circuits 5A and 5B having a plurality of fluorescent lamps 13A and 13B and connected to the field effect transistor FET3 are closed even if one of the fluorescent lamps 13A and 13B is thinned out. Is formed. Here, even if the resonance current flows in the closed circuit, the diode D2 as the cutoff circuit is prevented from flowing to the other load circuit 6. That is, even if one of the plurality of discharge lamps 13A, 13B is removed, the load circuits 5A, 5B and the other load circuits 6 are not affected.

  Next, a third embodiment of the present invention will be described.

  FIG. 4 is a circuit diagram of a discharge lamp lighting device showing a third embodiment of the present invention. Note that the same parts as those in FIG.

  The discharge lamp lighting device 21 shown in FIG. 4 is the same as the discharge lamp lighting device 1 shown in FIG. 1 except that the field effect transistor FET2 as the first switch element of the inverter circuit 4 and the field effect transistor FET3 as the second switch element. Components other than the FET 4, the diodes D2 and D4 as the cutoff circuit, and the diodes D3 and D5 as the discharge circuit are formed in the inverter circuit integrated circuit 22 together with the inverter circuit control circuit 7. In the inverter circuit 23, a level shift 24 that increases the level of the drive voltage output from the inverter circuit integrated circuit 22 is connected to the gate of the field effect transistor FET2.

  Since the discharge lamp lighting device 21 has the integrated circuit 22 for inverter circuits, the space for mounting the component parts on the circuit board is reduced, and the size is thereby reduced.

  The photoreceiver 15 is connected to the inverter circuit integrated circuit 22 and the chopper circuit control circuit 9 as the DC voltage source control means.

  When an external signal for turning off the fluorescent lamp 13 (fluorescent lamp 14) transmitted from the wireless transmitter to the light receiver 15 is input from the light receiver 15, for example, the inverter circuit integrated circuit 22 receives the field effect transistor FET 2 (field effect transistor). The on / off operation of the transistor FET3) is stopped, and the fluorescent lamp 13 (fluorescent lamp 14) is turned off.

  The chopper circuit control circuit 9 receives a dimming signal as an external signal that changes the light output of the fluorescent lamps 13 and 14 transmitted from the wireless transmitter to the light receiver 15, for example. Then, the on / off frequency of the field effect transistor FET1 of the chopper circuit 2B is changed according to the dimming signal, and the voltage generated between both ends of the smoothing capacitor C2 is changed. Here, the characteristics of components such as the inductor L1 and the on / off frequency of the field effect transistor FET1 are set in advance so that a predetermined voltage corresponding to the dimming signal is generated between both ends of the smoothing capacitor C2. That is, the chopper circuit 2B converts the DC voltage output from the DC voltage generation circuit 2A into a predetermined voltage and outputs it.

  The predetermined voltage generated between both ends of the smoothing capacitor C2 is the output voltage of the chopper circuit 2B and the input voltage of the inverter circuit 23. Therefore, when the predetermined voltage changes, the input voltage of the inverter circuit 23 changes. As a result, the high-frequency voltage between both ends of the field effect transistor FET3 and the field effect transistor FET4 of the inverter circuit 23 changes, and the resonance currents flowing through the load circuit 5 and the load circuit 6 change.

  When the resonance current changes, the discharge current between the filament electrodes 13a and 13b of the fluorescent lamp 13 and the discharge current between the filament electrodes 14a and 14b of the fluorescent lamp 14 change, so that the respective light outputs of the fluorescent lamp 13 and the fluorescent lamp 14 Changes. Thus, the fluorescent lamp 13 and the fluorescent lamp 14 are simultaneously dimmed according to a dimming signal that changes the light output of the fluorescent lamps 13 and 14 transmitted from, for example, a wireless transmitter.

  Next, a fourth embodiment of the present invention will be described.

  FIG. 5 is a circuit diagram of a discharge lamp lighting device showing a fourth embodiment of the present invention. The same parts as those in FIG.

  The discharge lamp lighting device 25 shown in FIG. 5 replaces the resonance capacitor C5 of the load circuit 5 with a series circuit of the resonance capacitor C11 and the resonance capacitor C12 in the discharge lamp lighting device 21 shown in FIG. The load circuit 27 is formed by replacing the resonance capacitor C7 of the load circuit 6 with the resonance capacitor C13 and the resonance capacitor C14. A field effect transistor FET5 as a capacity increasing / decreasing circuit is connected in parallel to the resonance capacitor C12 of the load circuit 26, and a field effect transistor FET6 as a capacity increasing / decreasing circuit is connected in parallel to the resonance capacitor C14 of the load circuit 27. Has been. The gates of the field effect transistors FET5 and FET6 are connected to the inverter circuit integrated circuit 22, respectively.

  In the load circuit 26, when the field effect transistor FET5 is turned off and both ends of the resonance capacitor C12 are opened, the resonance capacitor C11 and the resonance capacitor C12 are connected between the filament electrodes 13a and 13b of the fluorescent lamp 13, and the fluorescence The capacity of the resonance capacitor connected in parallel to the lamp 13 increases. Thereby, the resonance current flowing through the resonance capacitor is increased, and the fluorescent lamp 13 is dimmed (step dimming). In the load circuit 27, when the field effect transistor FET6 is turned off and both ends of the resonance capacitor C14 are opened, the resonance current flowing through the resonance capacitor increases as described above, and the fluorescent lamp 14 is dimmed (stepped). Light).

  For example, when an external signal (wireless signal) for adjusting the fluorescent lamp 13 or the fluorescent lamp 14 is transmitted from the wireless transmitter to the light receiver 15, the external signal is input from the light receiver 15 to the inverter circuit integrated circuit 22. Is done. In response to the external signal, the inverter circuit integrated circuit 22 turns off the field effect transistor FET5 or the field effect transistor FET6 to individually dim the fluorescent lamp 13 or the fluorescent lamp 14.

  Further, as described in the discharge lamp lighting device 21 shown in FIG. 3, the fluorescent lamp 13 or the fluorescent lamp 14 is a chopper circuit 2B by the chopper circuit control circuit 9 according to an external signal for dimming the fluorescent lamps 13 and 14. The light is adjusted at the same time by the control. Further, the fluorescent lamps 13 and 14 are individually turned off under the control of the inverter circuit integrated circuit 22 according to an external signal for turning off the fluorescent lamps 13 and 14. In this way, the fluorescent lamp 13 or the fluorescent lamp 14 can be dimmed, stepped dimmed, and extinguished as desired.

  Next, a fifth embodiment of the present invention will be described.

  FIG. 6 is an external view of a luminaire showing a fifth embodiment of the present invention. Note that the same parts as those in FIG.

  A lighting fixture 28 shown in FIG. 6 is a direct-mounted lighting fixture installed on a construction such as a ceiling. The lighting fixture main body 29, ring-shaped fluorescent lamps 30, 31, 32 having different ring outer diameters, a globe 33, and a discharge lamp are used. A lighting device 34 and a light receiver 15 are included.

  The annular fluorescent lamps 30, 31, and 32 are concentrically attached to the lamp sockets 35, 36, and 37 of the luminaire main body 29, respectively. The annular fluorescent lamps 30, 31, and 32 emit daylight white, daylight color, and light bulb color light having different color temperatures.

  A discharge lamp lighting device 34 is accommodated in the luminaire body 29 and connected to the annular fluorescent lamps 30, 31, 32. The discharge lamp lighting device 34 is configured by removing the fluorescent lamps 13 and 14 in the discharge lamp lighting device 1 shown in FIG. The light fixture main body 29 is provided with a light receiver 15 that receives a wireless signal (external signal) transmitted from a wireless transmitter (not shown) at a substantially central portion. The luminaire main body 15 is fixed to a construction such as a ceiling with screws or the like, and the front surface is covered with a translucent glove 33.

  When the discharge lamp lighting device 34 is supplied with power, the annular fluorescent lamps 30, 31, 32 are lit. The colored lights emitted from the annular fluorescent lamps 30, 31, and 32 are mixed and transmitted through the globe 33 and emitted from the lighting fixture 28.

  The lighting fixture 28 changes the color temperature of the emitted illumination light by individually thinning out the ring-shaped fluorescent lamps 30, 31, 32 having different color temperatures, or by adjusting the light. Therefore, it is possible to produce lighting according to the atmosphere.

The circuit diagram of the discharge lamp lighting device which shows the 1st Embodiment of this invention. Similarly, the circuit diagram of another load circuit. The circuit diagram of the discharge lamp lighting device which shows the 2nd Embodiment of this invention. The circuit diagram of the discharge lamp lighting device which shows the 3rd Embodiment of this invention. The circuit diagram of the discharge lamp lighting device which shows the 4th Embodiment of this invention. The partially notched front view of the lighting fixture which shows the 5th Embodiment of this invention.

Explanation of symbols

FET 5, FET 6... Field effect transistors Tr 1, Tr 2 as capacity increasing / decreasing circuits N-type bipolar transistors 1, 16, 21, 25... Discharge lamp lighting device 3. 5, 6, 26, 27 ... load circuit 7 ... inverter circuit control circuit 9 as inverter circuit control means 9 ... chopper circuit control circuits 19 and 20 as DC voltage source control means ... lamp as lamp connection detection means Connection circuit 28 ... lighting fixture 29 ... lighting fixture body

Claims (7)

A DC voltage source that outputs a DC voltage;
A first switch element, a plurality of second switch elements connected to the first switch element, a load circuit connected between both ends of the second switch element, and first and second switch elements First and second switches connected in series, having a plurality of cutoff circuits connected in between, and a discharge circuit connected in parallel to a series circuit including a first switch element and a cutoff circuit An inverter circuit that outputs a high-frequency voltage by an element being connected between outputs of a DC voltage source and alternately turning on and off;
An inverter circuit control means for controlling the on / off frequency of the first and second switch elements;
The cutoff circuit allows a current supplied from a DC voltage source to flow to the load circuit when the first switch element is on, and prevents a regenerative current of the load circuit from flowing to the other load circuit side when the first switch element is off. The discharge lamp lighting device is configured to discharge the regenerative current of the load circuit when the second switch element is turned off. Load circuit control means configured to be able to individually stop the on / off operation of the second switch element according to an external signal;
The discharge lamp lighting device according to claim 1, comprising: Lamp connection detecting means for detecting a connection state of the discharge lamp in the load circuit;
The load circuit control means stops the on / off operation of the second switch element to which the load circuit is connected according to a signal when the lamp connection detection means detects the disconnection of the discharge lamp in the load circuit. The discharge lamp lighting device according to claim 2, which is configured as described above. DC voltage source control means for controlling the output of the DC voltage source to change in response to an external signal;
4. The discharge lamp lighting device according to claim 1, wherein the light output of the discharge lamp of the load circuit is changed by changing the output of the DC voltage source in accordance with the external signal. 5. A capacity increasing / decreasing circuit for increasing / decreasing the capacity of the resonance capacitor;
The inverter circuit control means controls the capacity increasing / decreasing circuit to increase / decrease the capacity of the resonance capacitor according to the external signal, and the light output of the discharge lamp of the load circuit changes due to the increase / decrease of the capacity of the resonance capacitor. The discharge lamp lighting device according to any one of claims 1 to 4, characterized in that: A discharge lamp lighting device according to any one of claims 1 to 5;
A lighting fixture body provided with the discharge lamp lighting device;
The lighting fixture characterized by comprising.   The lighting apparatus according to claim 6, wherein the color temperature of the discharge lamp is different between at least two of the plurality of load circuits.

Images