JP2004047234A - Discharge lamp lighting device and illuminating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device surely starting a discharge lamp. <P>SOLUTION: The composite capacity of capacitors C12, C13 is more than 100 times of the suspension capacitor of the high-pressure discharge lamp 15. The capacitors C12, C13 and ballast L3 are resonated to increase an output voltage of an inverter circuit 61. A variation in in the stray capacitance of the high-pressure discharge lamp 15 can be ignored with no influence on the resonance frequency of an LC resonance circuit 63. The voltage of the starting pulse generated by the inverter circuit 61 in a non-load state when the high-pressure discharge lamp does not light can be increased by the resonance of the LC resonance circuit 63, to surely start the high-pressure discharge lamp 15. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a discharge lamp lighting device and a lighting device for lighting a discharge lamp by an inverter circuit.
[0002]
[Prior art]
Conventionally, as a discharge lamp lighting device of this type, for example, a configuration described in Japanese Patent Application Laid-Open No. 2000-58284 is known. In the discharge lamp lighting device described in Japanese Patent Application Laid-Open No. 2000-58284, a step-up chopper circuit is connected to a power supply, and an inverter circuit is connected to the step-up chopper circuit. Apply, start and light.
[0003]
At the time of starting, in order to start the discharge of the high-pressure discharge lamp, it is necessary to apply a starting pulse of a voltage higher than the discharge voltage to the high-pressure discharge lamp, and supply power to the inverter circuit with the output of the boost chopper circuit maximized. Then, a starting pulse is applied to the high-pressure discharge lamp.
[0004]
[Problems to be solved by the invention]
However, when a starting pulse is output by the inverter circuit in a state where the output of the chopper circuit is increased, there is a problem that the stress of the chopper circuit is increased and the size of the chopper circuit needs to be increased.
[0005]
The present invention has been made in view of the above problems, and has as its object to provide a discharge lamp lighting device and a lighting device that can reliably start a discharge lamp.
[0006]
[Means for Solving the Problems]
A discharge lamp lighting device according to claim 1 is provided with an electrode and a starting auxiliary body, a discharge lamp having a stray capacitance is connected between the electrode and the starting auxiliary body, and has a resonant inductor and a resonant capacitor. A main circuit including an LC resonance circuit having a capacitance not less than 100 times the stray capacitance of the lamp; this main circuit being connected to the output side, starting and lighting the discharge lamp via the main circuit, and an LC resonance circuit of the main circuit; And an inverter circuit that operates at the no-load resonance frequency.The capacitance of the resonance capacitor is 100 times or more the stray capacitance of the discharge lamp. Since the resonance frequency of the discharge lamp when the lamp is not lit and no load does not change without affecting the resonance of the resonance capacitor and resonance inductor, Data circuit operates at a resonant frequency at no-load.
[0007]
According to a second aspect of the present invention, there is provided a discharge lamp lighting device including an electrode and a starting auxiliary body, wherein a discharge lamp having a stray capacitance is connected between the electrode and the starting auxiliary body, and a resonant inductor is provided. A main circuit including an LC resonance circuit that operates; an inverter that is connected to the output side, starts and lights a discharge lamp through the main circuit, and operates at a resonance frequency of the LC resonance circuit of the main circuit when no load is applied. Circuit, and resonates with the stray capacitance between the electrode of the discharge lamp and the starting auxiliary body, eliminating the need for a resonance capacitor in the LC resonance circuit, simplifying the circuit configuration, and ensuring reliable operation. In a state where the lamp is not connected, the LC resonance circuit does not resonate and unnecessary stress does not occur.
[0008]
A lighting device according to a third aspect includes the discharge lamp lighting device according to the first or second aspect; and a fixture main body to which a discharge lamp to be lighted by the discharge lamp lighting device is attached, and has respective functions. .
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a lighting device of the present invention will be described with reference to a spotlight shown in the drawings.
[0010]
1 is a circuit diagram showing a discharge lamp lighting device, FIG. 2 is a cross-sectional view showing a spotlight, FIG. 3 is a side view showing a part of the high-pressure discharge lamp cut away, and FIG. FIG.
[0011]
As shown in FIG. 2, a spotlight 1 as a lighting device includes a spotlight body 2 as a fixture body, and the spotlight body 2 has a ceiling attachment part 3 attached to a ceiling or the like. Is provided with an arm 4. The arm 4 is provided with a case body 5 having an open front surface and a hollow inside, and a light portion 6 is provided facing the opening on the front surface of the case body 1. The light portion 6 has a cylindrical base portion 7, and a reflector 8 having a rotating reflection surface is attached to a base end side of the base portion 7. Is provided with a lamp socket 11, and a front glass 12 for closing the opening is provided at the tip of the base 7. Further, a high-pressure discharge lamp 15 such as a 20 W ceramic metal halide lamp is mounted on the lamp socket 11, and a cylindrical light-shielding body 16 is attached to a tip portion of the high-pressure discharge lamp 15 via a gap. The lamp socket 11 is electrically connected to a discharge lamp lighting device 18 shown in FIG.
[0012]
As shown in FIG. 3, the high-pressure discharge lamp 15 has a lamp base 21, on which a base 22 electrically and mechanically connected to the lamp socket 11 is formed. Has a cylindrical outer tube 23 whose light-transmitting tip is closed in an arc shape and whose inside is vacuum. An arc tube 24 is housed in the outer tube 23. The arc tube 24 has a discharge vessel 25 made of a translucent ceramic vessel. The surrounding portion 26 and small-diameter cylindrical portions 27 and 28 called capillaries which are continuously formed with curved surfaces in the vertical direction of the surrounding portion 26 are formed vertically symmetrically. Further, the distal ends of the small-diameter cylindrical portions 27 and 28 are closed by seals 31 and 32, and the upper introduction conductor 33 on the upper side is inserted into the seal 31 of the small-diameter cylindrical portion 27. The lower introduction conductor 34 on the lower side is inserted. Further, an external connection terminal 35 electrically connected to the base 22 is electrically connected to the upper introduction conductor 33, and the external connection terminal 35 is wound around the lower small-diameter cylindrical portion 28 to start. A getter 37 is supported while being electrically connected to a metal coil 36 as a body. Further, a metal coil 38 wound around the upper small-diameter cylindrical portion 27 as a starting auxiliary body is electrically connected to the lower introducing conductor 34, and the lower introducing conductor 34 is also electrically connected to the external connection terminal 35. It is electrically connected to the base 22 in an insulated state. A stray capacitance is formed between the electrodes 41 and 44 and the metal coils 36 and 38.
[0013]
Further, a discharge gas including a starting gas such as neon (Ne) or argon (Ar) is sealed in the discharge vessel 25, and is electrically connected to the upper introduction conductor 33 in the upper small-diameter cylindrical portion 27. The upper electrode 41 is attached, and the electrode 41 has a shaft portion 42 connected to the upper introducing conductor 33 and a coil portion 43 located in the surrounding portion 26 and attached to the tip of the shaft portion 42. On the other hand, a lower electrode 44 electrically connected to the lower introducing conductor 34 is provided in the lower small-diameter cylindrical portion 28 so as to face the upper electrode 41. It has a shaft portion 45 connected to the introduction conductor 34 and a lower coil portion 46 located in the surrounding portion 26 and attached to the tip of the shaft portion 45 and facing the upper coil portion 43. The metal coil 36 having a different polarity faces the electrode 41, the metal coil 38 having a different polarity also faces the electrode 44, and floats between the electrodes 41 and 44 and the metal coils 36 and 38. Forming a capacitance.
[0014]
Next, the discharge lamp lighting device 18 will be described with reference to FIG.
[0015]
First, a noise filter circuit 51 is connected to a commercial AC power supply e via a fuse F and a resistor R1. The noise filter circuit 51 is formed by connecting a capacitor C1 and a transformer Tr1, and is connected to a chopper circuit 52.
[0016]
In the chopper circuit 52, an AC input terminal of a diode bridge 53 as a full-wave rectifier of the diodes D1 to D4 is connected to the transformer Tr1, and a smoothing capacitor C2 as a smoothing unit is connected to an output terminal of the diode bridge 53. The chopper 54 is connected to the capacitor C2. Further, the chopper section 54 is connected in parallel with the capacitor C2 to a series circuit of an inductor L1, a field effect transistor Q1 as a switching element, and a resistor R2 for current detection, and is connected to a series circuit of the field effect transistor Q1 and the resistor R2. Is connected to a series circuit of a diode D5 and a capacitor C3.
[0017]
Further, a series circuit of a voltage dividing resistor R4 and a resistor R5 for detecting an input voltage is connected in parallel with the capacitor C2, and a connection point of the resistor R4 and the resistor R5 serves as a chopper circuit control means such as an ST microcontroller. It is connected to the No. 3 pin of IC55 of model number L6561. Similarly, in parallel with the capacitor C2, a starting circuit composed of a time constant circuit of the resistors R6, R7 and the capacitor C4 and a series circuit constituting a power supply are connected, and the resistor R7 and the capacitor C4 are connected. The connection point is connected to the eighth pin of the IC 55. Further, a detection winding L2 for detecting a current flowing through the inductor L1 is magnetically coupled to the inductor L1, and this detection winding L2 is connected to a fifth pin of the IC 55 via a resistor R3. It is connected to the sixth pin and the negative electrode of the diode bridge 53. The connection point between the detection winding L2 and the resistor R3 is connected to the negative electrode of the diode bridge 53 via a series circuit of a capacitor C5, a resistor R8, a diode D6 and a capacitor C6, and is connected to the series circuit of the diode D6 and the capacitor C6. The Zener diode ZD1 is connected in parallel, and the eighth pin of the IC 55 is connected to the connection point of the diode D6 and the capacitor C6.
[0018]
A capacitor C7 is connected between the first and second pins of the IC 55, and a third pin of the IC 55 is connected to the negative electrode of the diode bridge 53 via the capacitor C8. Further, the fourth pin of the IC 55 is connected to a connection point between the field effect transistor Q1 and the resistor R2, and the seventh pin of the IC 55 is connected to the gate of the field effect transistor Q1 via the resistor R9.
[0019]
The time constant of the resistor R6, the resistor R7, the capacitor C4, and the capacitor C6 of the starting circuit for starting the IC 55 of the chopper circuit 52 is set to 1 to 3 seconds, preferably about 2 seconds.
[0020]
Further, an output setting circuit 56 is connected in parallel with the capacitor C3. In the output setting circuit 56, a series circuit of a resistor R11, a resistor R12, and a resistor R13 is connected in parallel with the capacitor C3, and a connection point of the resistor R11 and the resistor R12 is connected via a diode D7 having an opposite polarity to the resistor R12. The connection point of the resistor R13 is connected to the feedback first pin of the IC 55 via a forward polarity diode D8. The operation of the field effect transistor Q1 is controlled by the voltage input to the first pin, so that the chopper circuit 52 is controlled to have a constant output voltage.
[0021]
A half-bridge type inverter circuit 61 is connected to the chopper circuit 52. The inverter circuit 61 has a series circuit of a field effect transistor Q2 and a field effect transistor Q3 as switching elements. The main circuit 62 is connected to the DC cut capacitor C11. The main circuit 62 includes a DC cut capacitor C11, a ballast L3 as a resonance inductor, a capacitor C12 as a resonance capacitor, and an LC of a series circuit of a capacitor C13. The resonance circuit 63 is connected to a resistor R14 and a current detection circuit 64 of a series circuit of a diode D12 and a diode D11 connected in parallel to the resistor R14. Note that the resonance frequency of the LC resonance circuit 63 is any frequency in the range of 20 kHz to 500 kHz, and the combined capacitance of the capacitor C12 and the capacitor C13 as the resonance capacitor corresponds to the electrodes 41 and 44 of the high-pressure discharge lamp 15 and the metal coil. The capacitance is about 100 times larger than the stray capacitance between 36 and 38.
[0022]
The inverter circuit 61 has a control circuit 65. The control circuit 65 is connected to a series circuit of a resistor R15 and a resistor R16 from a connection point of the diode D5 and the field effect transistor Q2, and has a phase oscillation detection means and a pulse height control. For example, it is connected to pin 13 of IC66 of model number UBA2021 manufactured by Philips Semiconductor as an inverter circuit control means that also functions as a circuit, and a capacitor C15 is connected between pins 5 and 7 of this IC66. A starting circuit composed of a time constant circuit of R16 and a capacitor C15 is formed. A series circuit of a diode D15 and a diode D16 is connected in parallel to the capacitor C15. Through It is connected to the connection point of the field effect transistor Q2 and the field-effect transistors Q3, a capacitor C16, the diode D15, the diode D16 and the capacitor C15 constitute a power IC 66.
[0023]
Further, the resistor R16 is connected to the gate of the field effect transistor Q4, a series circuit of the resistors R17 and R18 is connected between the source and the drain of the field effect transistor Q4, and the connection point of the resistors R17 and R18 is connected to the resistor R19. Is connected to the 10th pin of the IC 66, and a capacitor C17 is connected in parallel with the series circuit of the resistor R18 and the resistor R19. The source of the field effect transistor Q4 is connected to the 14th pin of the IC66 via the capacitor C18, to the 12th pin of the IC66 via the capacitor C19, to the 8th pin of the IC66 via the capacitor C20, and directly to the 11th pin of the IC66. Connected to pins.
[0024]
A resistor R21 is connected between the fifth and ninth pins of the IC 66, a resistor R22 is connected between the ninth and seventh pins of the IC 66, and the first and third pins of the IC 66 are connected. A capacitor C21 is connected between them, and a third pin of the IC 66 is connected to a connection point between the field effect transistor Q2 and the field effect transistor Q3. Then, the field effect transistor Q2 and the field effect transistor Q3 of the inverter circuit 61 are operated at the above-mentioned set frequency in the range of 20 kHz to 500 kHz which is the resonance frequency at the time of no-load resonance when the high-pressure discharge lamp 15 is not turned on. .
[0025]
Further, the gate of the field effect transistor Q2 is connected to the second pin of the IC 66, the gate of the field effect transistor Q3 is connected to the sixth pin of the IC 66, and the field effect transistor Q2 and the field effect transistor Q3 are alternately turned on. Turn off.
[0026]
The time constant of the resistor R15, the resistor R16 and the capacitor C15 of the starting circuit for starting the IC 66 of the inverter circuit 61 is set within 1 second, and the resistors R6, R7 and R7 of the starting circuit for starting the IC 55 of the chopper circuit 52 are set. By setting the time constant of the capacitor C4 and the capacitor C6 to be shorter than about 2 seconds, the IC 66 operates first to output the inverter circuit 61 after the set time elapses after the power is turned on, and then the IC 55 operates to operate the chopper circuit. 52 is output.
[0027]
One end of the high-pressure discharge lamp 15 is connected to a connection point between the ballast L3 and the capacitor C12, and the other end of the high-pressure discharge lamp 15 is connected via a lamp power detection circuit 67 to a connection point between the field-effect transistor Q3 and the resistor R14. It is connected to the.
[0028]
In the lamp power detection circuit 67, a current detecting resistor R31 having a relatively small resistance value is connected in series to the high-pressure discharge lamp 15 and is sufficiently parallel to the high-pressure discharge lamp 15 compared to the resistor R31. Is connected in parallel with a series circuit of a resistor R32 and a resistor R33 having a high resistance value. The connection point between the resistance R32 and the resistance R33 is connected to the connection point between the diode D7 and the diode D8 via the diode D17 and the resistance R34, and the connection point between the diode D17 and the resistance R34 is connected via the capacitor C21 to the field effect transistor Q3. It is connected to the connection point of the resistor R14.
[0029]
A starting pulse generating circuit 68 is connected in parallel to the high-pressure discharge lamp 15 and the lamp power detecting circuit 67. The starting pulse generating circuit 68 is connected in parallel to the high-pressure discharge lamp 15 and the resistor R31, and to a resistor R36 and a resistor R36. A series circuit of R37 is connected, a capacitor C22 is connected to a connection point of the resistor R36 and the resistor R37, and the capacitor C22 is connected to both ends of the capacitor C23 via a diode D21 and a diode D22. Further, a series circuit of a Zener diode ZD2 and a capacitor C24 is connected in parallel with the capacitor C23, a resistor R38 is connected in parallel with the capacitor C24, and a connection point of the Zener diode ZD2 and the capacitor C24 is connected to a field effect transistor Q5. , And the drain and source of the field effect transistor Q5 are connected to the 5th and 7th pins of the IC 66, respectively.
[0030]
Next, the operation of the above embodiment will be described.
[0031]
First, when the commercial AC power supply e is turned on, full-wave rectification is performed by the diode bridge 53, smoothed by the capacitor C <b> 2, and a DC voltage is applied to the chopper circuit 52. Further, the voltage is smoothed by the capacitor C3 and a DC voltage is applied to the inverter circuit 61. Since the IC 55 does not operate for about two seconds after the power is turned on, the chopper circuit 57 does not operate and outputs the output voltage of the capacitor C3 which does not boost.
[0032]
Since the IC 66 starts operating within one second after the power is turned on, the field effect transistors Q2 and Q3 are alternately turned on at the no-load resonance frequency of the LC resonance circuit 63 before the chopper circuit 52 starts operating. Off, and the voltage resonated by the LC resonance circuit 63 is applied to the high-pressure discharge lamp 15. When the inverter circuit 61 oscillates at a frequency in the phase-advance region by detecting the current of the main circuit 62 by the current detection circuit 64 and functioning as a phase-initiated oscillation detection means of the IC 66, the no-load resonance frequency Control to operate at a nearby frequency. Then, the high-pressure discharge lamp 15 is in a no-load state in which it is not lit, so that the voltage is high, the voltages of the resistors R36 and R37 also rise, the zener diode ZD2 is turned on, and the capacitor C24 is charged. When the capacitor C24 is charged, the field effect transistor Q5 is turned on, the pin Nos. 5 and 7 of the IC 66 are short-circuited, the capacitor C15 is short-circuited, the output of the IC 66 is stopped, and the field effect transistor Q2 and the electric field Each of the effect transistors Q3 is turned off. That is, when the IC 66 is on, high-frequency AC is output from the inverter circuit 61, and when the IC 66 is off, the output of the inverter circuit 61 is stopped, and a starting pulse is applied to the high-pressure discharge lamp 15. At this time, by detecting the current flowing through the resistor R14, the IC 66 controls on / off of the field effect transistor Q2 and the field effect transistor Q3 so as to control the starting pulse height to be constant. The ON time of the starting pulse is set by the charging time of the capacitor C24, and the OFF time is set by using the discharging time of the capacitor C24 and the charging time constant of the power supply of the IC 66 determined by the resistors R15, R16 and C15. .
[0033]
Then, about two seconds after the power supply at which the high-pressure discharge lamp 15 starts glow discharge, the IC 55 of the chopper circuit 52 starts operating, and when the high-pressure discharge lamp 15 starts glow discharge, the voltage of the high-pressure discharge lamp 15 decreases. Then, the voltage of the resistor R32 and the voltage of the resistor R33 decrease and the voltage of the resistor R31 increases, and the added voltage is the power of the high-pressure discharge lamp 15 and is applied to the connection point between the diode D7 and the diode D8. Since the voltages of the diodes D7 and D8 are lower than the state where the high-pressure discharge lamp 15 is not lit, a current is input to the first pin of the IC 55 via the diode D8, and the IC 55 turns on the field effect transistor Q1. Off, and operate the chopper circuit 52 at the maximum voltage set by the output setting circuit 56. Pressure, by applying a voltage boosted to the inverter circuit 61, inverter circuit 61 is operated by the boosted voltage, a voltage is applied to the high-pressure discharge lamp 15, to ensure glow arc transition. The resistor R31 also detects the current of the high-pressure discharge lamp 15, and the resistors R32 and R33 also detect the voltage. Since both are resistance components, the current and the voltage can be detected in the same phase. And the voltage, the power of the high-pressure discharge lamp 15 can be detected. As described above, since the chopper circuit 52 operates at a predetermined time after the operation of the inverter circuit 61, particularly in the high-pressure discharge lamp 15 using neon (Ne) or argon (Ar), one second or more is required for arc transition. A glow discharge time is secured by applying a high open-circuit voltage for about 3 seconds, so that the glow arc transition time can be appropriately set, thereby preventing the high pressure discharge lamp 15 from being stressed.
[0034]
The chopper circuit 52 outputs an output set by the output setting circuit 56 based on the potentials of the resistors R4 and R5 corresponding to the input voltage and the potentials of the diodes D7 and D8 corresponding to the power of the high-pressure discharge lamp 15. The output voltage of the chopper circuit 52 is controlled within the voltage range.
[0035]
Further, the voltage applied to the field effect transistor Q2 and the field effect transistor Q3 is detected by the resistors R15 and R16, and the apparent resistance value between the source and the drain of the field effect transistor Q4 is changed. The output of the inverter circuit 61 is controlled by controlling the frequency of Q2 and the frequency of the field effect transistor Q3.
[0036]
According to the above embodiment, the combined capacitance of the capacitors C12 and C13, which are resonance capacitors, is set to be 100 times or more the stray capacitance of the high-pressure discharge lamp 15, so that even if the stray capacitance of the high-pressure discharge lamp 15 varies, Since the stray capacitance of the lamp 15 can be neglected and the resonance frequency of the LC resonance circuit 63 is not affected, the voltage of the starting pulse generated by the inverter circuit 61 in a no-load state where the high-pressure discharge lamp 15 is not turned on is changed to the LC resonance circuit 63. And the high-pressure discharge lamp 15 can be reliably started.
[0037]
Then, by securing the glow discharge time, any one of the electrodes 41 and 44 of the high-pressure discharge lamp 15 can be sufficiently heated and heated, so that only one of the electrodes 41 and 44 is unbalancedly heated. As a result, a half-wave arc is not generated, spattering of the electrodes 41 and 44 on the glow side is promoted, and the flickering blackening characteristic is prevented from being lowered, thereby preventing the luminous efficiency from being lowered.
[0038]
Further, in the state where the starting pulse is generated, the stress applied to the chopper circuit 52 can be reduced by not operating the chopper circuit 52, so that the withstand voltage of the field effect transistor Q1 and other components can be reduced, and the chopper circuit 52 The size can be reduced.
[0039]
In the above embodiment, the chopper circuit 52 is not operated for a predetermined time from the start of the inverter circuit 61 to the start of the chopper circuit 52, but the output setting circuit 56 outputs a start pulse. In such a state, a constant state may be set at the lowest voltage that can be set by the output voltage of the chopper circuit 52.
[0040]
Next, another embodiment will be described with reference to FIG.
[0041]
FIG. 5 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. The circuit is basically the same as that of the discharge lamp lighting device 18 shown in FIG. 1, except for the capacitors C12 and C13 as resonance capacitors. The resonance is caused by the stray capacitance of the high-pressure discharge lamp 15 and the ballast L3 as a resonance inductor. The high-pressure discharge lamp 15 has a double structure of the outer tube 23 and the arc tube 24. Since the inside of the outer tube 23 is vacuum, a sufficiently high voltage can be generated between the floating capacities.
[0042]
The basic operation is the same as that of the discharge lamp lighting device 18 shown in FIG. 1, except that the resonance frequency of the LC resonance circuit 63 when the LC resonance circuit 63 is not loaded is determined by the resonance of the high-pressure discharge lamp 15 and the ballast L3. Even if the stray capacitance of the discharge lamp 15 varies, the IC 66 always oscillates the oscillation frequency of the inverter circuit 61 in accordance with the no-load resonance frequency by the phase advance oscillation detection function of the IC 66. Resonance can be achieved, and a sufficiently high starting pulse can be obtained by the inverter circuit 61.
[0043]
Further, when the high-pressure discharge lamp 15 is disconnected, the high-pressure discharge lamp 15 serving as a resonance capacitor disappears, and the LC resonance circuit 63 does not resonate, so that no resonance voltage is generated. It is possible to prevent stress or noise from being applied to the device 61 or the like.
[0044]
Further, when gas flows out of the arc tube 24 into the outer tube 23 at the end of the life of the high-pressure discharge lamp 15 or when the outer tube 23 leaks, discharge occurs between the floating capacities at a relatively low voltage. , The discharge cannot be started between the electrodes 41 and 44, and abnormal discharge is prevented.
[0045]
【The invention's effect】
According to the discharge lamp lighting device of the first aspect, since the capacitance of the resonance capacitor is set to be 100 times or more the stray capacitance of the discharge lamp, even if the stray capacitance of the discharge lamp varies, the resonance capacitor and the resonance inductor can be used. Since the resonance frequency at the time of no load when the discharge lamp is not lit does not change without affecting the resonance of the discharge lamp, the inverter circuit can reliably operate at the resonance frequency at the time of no load.
[0046]
According to the discharge lamp lighting device according to the second aspect, by resonating with the stray capacitance between the electrode of the discharge lamp and the starting auxiliary body, the resonance capacitor of the LC resonance circuit is not required, and the circuit configuration is simple and reliable. In addition to operation, the LC resonance circuit does not resonate when the discharge lamp is not connected, thereby preventing unnecessary stress or the like from occurring.
[0047]
According to the lighting device of the third aspect, since the apparatus main body to which the discharge lamp lit by the discharge lamp lighting device of the first or second aspect is attached, each effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing one embodiment of a discharge lamp lighting device according to the present invention.
FIG. 2 is a cross-sectional view showing the same spotlight.
FIG. 3 is a side view showing the high pressure discharge lamp with a part cut away.
FIG. 4 is a side view showing the arc tube of the high-pressure discharge lamp cut away.
FIG. 5 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Spotlight as a lighting device 2 Spotlight body 15 as a fixture main body High-pressure discharge lamp 18 Discharge lamp lighting device 36, 38 Metal coils 41, 44 as a starting auxiliary body Electrode 61 Inverter circuit 62 Main circuit 63 LC resonance circuit C12, C13 Resonant capacitor L3 Ballast as resonant inductor

Claims (3)

A discharge lamp having a stray capacitance is connected between the electrode and the starting auxiliary body, and has a resonance inductor and a resonance capacitor. The capacitance of the resonance capacitor is 100 times or more the stray capacitance of the discharge lamp. A main circuit including an LC resonance circuit;
An inverter circuit connected to the output side for starting and lighting the discharge lamp via the main circuit, and operating at a no-load resonance frequency of the LC resonance circuit of the main circuit;
A discharge lamp lighting device comprising: A main circuit including an electrode and a starting auxiliary body, a discharge lamp having a stray capacitance connected between the electrode and the starting auxiliary body, including a resonant inductor, and an LC resonant circuit resonating with the stray capacitance of the discharge lamp and the resonant inductor;
An inverter circuit connected to the output side for starting and lighting the discharge lamp via the main circuit, and operating at a no-load resonance frequency of the LC resonance circuit of the main circuit;
A discharge lamp lighting device comprising: A discharge lamp lighting device according to claim 1 or 2;
An appliance body to which a discharge lamp to be lit by the discharge lamp lighting device is attached;
A lighting device, comprising:

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