JPH0773984A - Electrodeless lamp lighting device and lighting system - Google Patents

Abstract

(57) [Summary] [Purpose] To facilitate the design and adjustment of the device, and to perform stable operation even with changes over time. [Structure] At the time of starting, a high-frequency current required for normal lighting is supplied to the excitation coil L _{C from} a high-frequency power supply generation circuit 4 through a matching circuit 5, and a switch 8 is turned on, so that the power supply 7 causes a start-up circuit 6 to operate. Since a direct current is supplied and a high voltage is generated in the starting circuit 6 and applied to the electrode 3, glow discharge is generated in the auxiliary discharge tube 1-2, and this enters the arc tube 1-1. At this time, electromagnetic energy is supplied from the excitation coil L _C and the coil L _ST to the arc tube 1-1, and the arc tube 1-1 makes a glow arc transition.
_A larger amount of electromagnetic energy is supplied from _C into the arc tube 1-1, and the non-electrification pole lamp 1 is turned on. As a result, the main circuit on the side of the excitation coil L _C and the starting circuit 6 are independent of each other, and only have to perform a single function, the design and adjustment of each circuit can be facilitated, and stable operation can be ensured even with time. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrodeless lamp lighting device and a lighting device for lighting an electrodeless lamp, and more particularly to a starting circuit for causing glow discharge in an auxiliary discharge tube of the electrodeless lamp.

[0002]

2. Description of the Related Art FIG. 10 is a circuit diagram showing an example of a conventional electrodeless lamp lighting device of this type. By switching the field effect transistors (hereinafter referred to as FETs) Q1 and Q2 that form the high frequency current generation circuit, a high frequency current is generated from the connection point of the transistors Q1 and Q2.
This high-frequency current is supplied to the excitation coil L _P via capacitors C _S and C _P that form a matching circuit. Since the switch 8 is turned on when the electrodeless lamp 1 is started, a high frequency current is supplied from the output side of the matching circuit to the starting circuit side including the capacitor C _st , the coil L _ST and the resistor R _ST . As a result, a high voltage is generated on the starting circuit side, and this high voltage is applied to the electrode 3. As a result, a glow discharge is generated in the auxiliary discharge tube 2, this glow discharge is further generated in the electrodeless lamp 1, and the electromagnetic energy generated in the excitation coil L _P is supplied to the electrodeless lamp 1. The glow arc transition is made in the electrodeless lamp 1. As a result, the ring plasma formed in the electrodeless lamp 1 and the excitation coil L _P are electromagnetically coupled, and a large amount of electromagnetic energy generated in the excitation coil L _P is supplied to the electrodeless lamp 1 and The electrode lamp 1 is turned on with all light. Then, the switch 8 is turned off and the starting circuit is disconnected from the output side of the matching circuit.

The starting circuit of the conventional electrodeless lighting device as described above includes (a) supply of the dielectric breakdown voltage between the auxiliary discharge tube 2 and the low potential side of the excitation coil L _P , and (b) ring plasma formation. adjust the output impedance as seen from the previous high-frequency current generating circuit side, excites the desired excitation current coil L _P
It has two functions: In order to actually design a starting circuit having such a configuration, a great deal of labor is required to find an adjustment point for having the above-mentioned two functions (a) and (b). Moreover, there are many so-called pseudo adjustment points, for example, there are many points (ranges) that satisfy (a) but not (b) around the adjustment points that have been found,
The coordinator requires a considerable amount of skill to search for and adjust the original adjustment point, and there is a drawback in that not only the production process but also the development efficiency becomes very poor. The reason for this is that the electrodeless lamp 1 and the electrodeless lamp lighting device are magnetically connected, the voltage / current value around the excitation coil L _P is large, and the operating frequency is three digits higher than that of the conventional inverter lighting device. Because it is expensive, it is not possible to obtain direct observation means for obtaining various characteristics of the circuit.

Further, since the above-mentioned electrodeless lamp lighting device has a very high Q in terms of circuit, even if somehow an adjustment point is found, the impedance deviation of each part due to the variation of each element or the change over time becomes fatal. Since the electrodeless lamp 1 may have a defect, or the switching element of the high frequency power supply circuit may be destroyed, the starting circuit is operated by being connected to the main circuit side including the excitation coil L _P and the high frequency generating circuit as in the conventional case. The electrodeless lamp lighting device has a drawback that it is difficult to adjust and the circuit is unstable against changes with time.

[0005]

SUMMARY OF THE INVENTION In an electrodeless lamp lighting device provided with a starting circuit for generating a high voltage for starting the electrodeless lamp 1 by receiving the high frequency current supplied to the excitation coil as described above, The starting circuit had to have two functions of generating a high voltage and adjusting the impedance of the output side as seen from the side of the high frequency power supply circuit before the ring plasma was formed in the electrodeless lamp. For this reason, it is difficult to find an adjustment point having both of the above two effects when designing the starting circuit, which requires a lot of labor and time, and requires skill in adjustment, resulting in poor production and development efficiency. There was a flaw. Moreover, the main circuit that supplies electromagnetic energy to the electrodeless lamp must be designed in consideration of supplying a part of high-frequency current to the starting circuit, and the operating frequency is higher than that of a normal inverter lighting device. Since it is about three orders of magnitude higher, there is also a drawback that the design is difficult because there is no direct observation means for obtaining various characteristics necessary for circuit design including the starting circuit. Furthermore, since the Q of the circuit is high, variations in the elements that make up the device and impedance shifts in each part due to changes over time may cause defects in the lamp and even damage to the device, making the device unstable and reliable. It had the disadvantage of lacking sex.

Therefore, the present invention eliminates the above-mentioned drawbacks, is easy to design and adjust, and has a highly reliable electrodeless lamp lighting device capable of performing stable operation with respect to changes with time, and the electrodeless lamp. It is an object of the present invention to provide a lighting device including a lighting fixture that accommodates the.

[0007]

According to the present invention, there is provided a high-frequency current generating circuit, an exciting coil to which a high-frequency current generated from the high-frequency current generating circuit is supplied, and an electromagnetic energy generated by the exciting coil. An electrode lamp, a starting circuit for generating a high voltage applied to an auxiliary discharge tube coupled to the arc tube of the electrodeless lamp for a predetermined period at the time of starting, and a power supply circuit for supplying electric power for operating the starting circuit. The high frequency current generating circuit is electrically separated from the high frequency current generating circuit.

[0008]

In the electrodeless lamp lighting device of the present invention, the main circuit including the excitation coil and the high-frequency current generating circuit for generating the high-frequency current supplied to the excitation coil maintains the lighting during the normal lighting of the electrodeless lamp. Since it is only necessary to supply the electromagnetic energy necessary for the start-up, it is not necessary to generate the high-frequency current for operating the starting circuit and the excessive electromagnetic energy to be supplied to the electrodeless lamp side at the time of starting, unlike the conventional design. Also, it is easy to adjust and operates relatively stably against variations in parts and changes with time. In addition, since the starting circuit for applying a high voltage to the auxiliary discharge tube coupled to the arc tube of the electrodeless lamp at the time of starting the electrodeless lamp is a power source separate from the main circuit and operates independently, It suffices to generate a high voltage for causing a glow discharge in the auxiliary discharge tube, the design and adjustment can be significantly facilitated, and the development efficiency and production efficiency of the device can be improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the electrodeless discharge lamp lighting device and lighting device of the present invention will be described below with reference to the drawings. Figure 1
2 is a block diagram showing an embodiment of the electrodeless lamp lighting device of the present invention, and FIG. 2 shows an embodiment of a lighting device to which the electrodeless discharge lamp lighting device is applied. Reference numeral 1 denotes an electrodeless lamp in which a rare gas is enclosed, which is composed of an arc tube 1-1 and an auxiliary discharge tube 1-2 for causing glow discharge for starting the electrodeless lamp 1. Reference numeral 3 denotes an electrode to which a high voltage is applied from a starting circuit 6 described later, which is an auxiliary discharge tube 1-
It is attached to the tip of 2. Reference numeral 4 is a high frequency power supply generation circuit that generates a high frequency current supplied to the excitation coil L _C.
Is a matching circuit that connects the high-frequency power supply generation circuit 4 and the excitation coil L _C , 6 is a starting circuit that generates a high voltage for causing glow discharge in the auxiliary discharge tube 1-2 when the electrodeless lamp 1 is started, Reference numeral 7 is a power source for the starting circuit that supplies DC power to the starting circuit 6, and 8 is a starting circuit 6 for the power source 7 for the starting circuit
It is a switch for switching off. Here, the starting circuit 6 is composed of a series resonant circuit consisting of coil L _ST and a capacitor C _ST, the resistance R _ST which is connected in parallel with the capacitor C _ST is an damping resistor. The electrodeless lamp lighting device configured as described above is housed in, for example, a lighting device as shown in FIG. In FIG. 2, an electrodeless discharge lamp 1 (hereinafter, simply referred to as a lamp) is provided via a socket 31 at the center of the lower surface of a base plate 30 as a plate member formed of a heat-resistant plastic or metal in a circular shape. There is. At the top of the lamp 1, there is a starting thin tube 1b.
A high voltage for starting is applied from the starter circuit 6 to the tip portion of the starting thin tube 1b protruding from the base plate 30.

The base end of the excitation coil 32 is fixed to the lower surface of the base plate 30 with a screw, and the excitation coil 32 is wound around the outer peripheral portion of the lamp 1. Further, the lamp 1 and the excitation coil 32 are covered with a cover 33 formed of acrylic resin in a hemispherical shape, and an upper end edge of the cover 33 is fixed to an outer peripheral portion of the base plate 30.
The cover 33 not only adjusts the light distribution of the lamp 1, but also prevents the lamp 1 and the excitation coil 32 from touching with hands, and prevents dust and insects from entering.

On the other hand, an excitation coil 32 and a lamp lighting device 34 are arranged on the upper surface of the base plate 30. A heat pipe 36 connected to an external radiator 35 is projected from the lamp lighting device 34. In the lighting device configured as described above, the radiant heat generated from the lamp 1 is blocked by the base plate 30 and is not transmitted to the lamp lighting device 34. Also, the lamp lighting device 3
The heat generated in 4 is transmitted to the external radiator 35 via the heat pipe 36, and is advantageously radiated to the outside.

Next, the operation of this embodiment will be described. When the electrodeless lamp 1 is started, a high frequency current is supplied from the high frequency power supply generation circuit 4 to the excitation coil L _C via the matching circuit 5. At this time, the high-frequency current flowing through the excitation coil L _C has a magnitude necessary for normally lighting the electrodeless lamp 1. After the high frequency current is supplied from the high frequency power supply generation circuit 4 to the excitation coil L _C , the switch 8 is turned on. As a result, a DC current of about 1 KV from the starting circuit power supply 7 flows into the series circuit of the coil L _ST and the capacitor C _ST of the starting circuit 6. At this time, current IL _ST flow as the coil L _ST shown in FIG. 3, and the connection point of the coil L _ST and the capacitor C _ST generated voltage as shown in FIG. 4, this voltage electrode 3 Is applied. The auxiliary discharge tube 1-2 at this time is shown in FIG.
A current I _Cg flows as shown in.

That is, the voltage applied to the electrode 3 begins to rise as shown in FIG. 4 after the switch 8 is turned on, and tn
The voltage after 2 seconds causes dielectric breakdown in the auxiliary discharge tube 1-2 to form glow discharge. Therefore, the current I _Cg in the auxiliary discharge tube 1-2 after tn seconds rapidly rises as shown in FIG. 5, and at this time, the current I _Cg flowing through the coil L _ST.
L _ST also becomes maximum as shown in FIG. It should be noted that the voltage shown in FIG. 4 is supposed to have a maximum value and be saturated after tn seconds, but the voltage is shown here for the sake of simulation. 6 is a diagram showing the waveforms of the apparent power a and the active power b supplied to the starting circuit 6 from the starting circuit power supply 7 through the switch 8. The active power also increases after the switch 8 is turned on. Then, as described above, the effective power becomes maximum immediately after the glow discharge is generated in the auxiliary discharge tube 1-2. Thus, the auxiliary discharge tube 2
When glow discharge is formed inside, the glow discharge enters the arc tube 1-1 in the electrodeless lamp 1. Electromagnetic energy generated in the excitation coil L _C along with this is supplied into the arc tube 1-1 of the electrodeless lamp 1, and the coil L _ST
Electromagnetic energy generated in the arc tube 1 of the electrodeless lamp 1
-1, the arc tube 1-1 of the electrodeless lamp 1 is supplied.
Inside the glow arc transition occurs and a ring plasma is formed. Since this ring plasma to electromagnetically couple with the excitation coil L _C, the electromagnetic energy is further large amount supplied to the ring plasma side from the excitation coil L _C, electrodeless lamp 1 is turned on all the light. After that, the switch 8 is turned off and the operation of the starting circuit 6 is stopped.

According to the present embodiment, the main circuit composed of the high-frequency power generation circuit 4 and the matching circuit 5 for supplying a high-frequency current to the excitation coil L _C of the excitation coil L _C Toko,
The starting circuit 6 and the starting circuit power source 7 are independently configured,
Since the starting circuit 6 only has the function of supplying the dielectric breakdown voltage between the auxiliary discharge tube 1-2 and the low potential side of the excitation coil L _P , the starting circuit 6 can be easily designed. The adjustment can be remarkably simplified, and anyone can adjust it, thus improving the production efficiency and development efficiency of the device. At the same time, the main circuit only needs to be able to supply the electromagnetic energy capable of maintaining the lighting of the electrodeless lamp 1, so that the load on the high-frequency power supply generation circuit 4 can be reduced, the design becomes easy, and the glow generation → glow arc transition occurs. The electrodeless lamp 1 can be lit by following the same definite steps as the starting step of the electroded HID, namely, energy superimposition → arc maintenance, and the operation mode is simplified, and the degree of freedom in designing the main circuit is expanded. You can Therefore, even if the impedance of each part is varied due to variations in each element or changes with time, the defect of the electrodeless lamp 1 or the destruction of the circuit is not immediately lost, and stable operation can be ensured.

In this example, the arc tube 1 of the electrodeless lamp 1
In addition to the excitation coil L _C , the coil L _ST is also arranged in the vicinity of 1 so as to have a large light-shielding property.
However, since the current flowing through the coil L _ST is smaller than the current flowing through the excitation coil L _C and has a shorter period, the coil L _ST can be configured by a thin line, and the light shielding property is not increased so much. Also, the number of turns of the coil L _ST can be increased because the wire is thin, and the magnetic flux density generated can be increased even if a small amount of current flows, so that electromagnetic energy at the time of starting can be considerably supplied to the electrodeless lamp 1. It has become.

In the embodiment shown in FIG. 1, the electromagnetic energy from the coil L _ST of the starting circuit 6 is superposed on the electromagnetic energy from the excitation coil L _C and the arc tube 1 of the electrodeless lamp 1-
Although the coil L _ST is arranged so as to be supplied into the electrode 1, the electrodeless lamp 1 receives electromagnetic energy from the coil L _ST.
The main circuit and the starting circuit 6 without being supplied inside.
Can be separated, and in such a configuration, although the power supply capacity of the high frequency power supply generation circuit 4 is somewhat large, the same effect as in the previous embodiment can be obtained.

The electrodeless lamp 1 and the auxiliary discharge tube 1-2 shown in FIG. 1 are entirely made of quartz. Prior to such main discharge of the arc tube 1-1 of the electrodeless lamp 1, a high voltage is applied from the starting circuit 6 to the auxiliary discharge tube 1-2 to cause glow discharge therein. The larger the glow current flowing in the auxiliary discharge tube 1-2, the easier the starting of the electrodeless lamp 1. However, this glow current is limited by the capacitance of the path from the electrode 3 that applies the high voltage to the auxiliary discharge tube 1-2 to the excitation coil L _C , so to increase the glow current, the starting circuit is required. 6
Therefore, an extremely high voltage must be applied to the electrode 3, which makes it difficult to design the starting circuit 6 for insulation. FIG. 7 is a diagram showing another embodiment for solving such a drawback.

FIG. 7 is a view showing the main part of another embodiment of the present invention. The arc tube 1-1 of the electrodeless lamp 1 of this example and the auxiliary discharge tube 1-2 coupled thereto are the auxiliary discharge tube 1-
The portion (hatched portion) (1) adjacent to the electrode 3 of ₂ is made of a material having a higher dielectric constant than quartz such as alumina (Al ₂ O ₃ ), and the auxiliary discharge tube 1-2 and the arc tube. 1-1
The connecting portion (hatched portion) b is also made of a high dielectric constant material such as alumina, and the portion (hatched portion) c adjacent to the excitation coil L _C of the arc tube 1-1 is also a high dielectric constant material such as alumina. Is made of. However, the rest is made of quartz as before.

FIG. 8 is a diagram showing an equalization circuit of a glow discharge path formed when glow discharge occurs in the auxiliary discharge tube 1-2 shown in FIG. Discharge path is capacitor C
1, a resistor R1, a capacitor C2, a resistor R2, and a capacitor C3. Where capacitor C
1 corresponds to a part of the wall of the auxiliary discharge tube 1-2 in contact with the electrode 3 of FIG. 7, the capacitor C2 corresponds to a partition wall B of the connecting portion of the arc tube 1-1 and the auxiliary discharge tube 1-2, and C3 corresponds to the equatorial wall _c adjacent to the excitation coil L _C of the arc tube 1-1. Therefore, the resistance R1 corresponds to the resistance of the discharge path from the portion a to the portion b of the auxiliary discharge tube 1-2,
The resistance R2 corresponds to the resistance of the discharge path from the portion B to the portion C.

Parts a, b, and c corresponding to the above-mentioned capacitors C1, C2, and C3 on the outer wall of the electrodeless lamp 1 of this example are made of alumina having a dielectric constant of 9 to 10, so that they are different from conventional ones. It is possible to increase the capacitance of each capacitor as compared with the case where it is made of quartz having a dielectric constant of 3.8. Therefore, if the impedance of the equalization circuit shown in FIG. 8 is lowered and the voltage applied to the electrode 3 is the same, a larger glow current than in the conventional case can be obtained.
Therefore, the electrodeless lamp 1 can be easily turned on. Further, particularly when restarting the electrodeless lamp 1 is difficult, it is possible to restart the electrodeless lamp 1 relatively easily because the glow current is large.
Further, when the starting performance of the electrodeless lamp 1 is as good as the conventional one, the voltage applied from the starting circuit 6 to the electrode 3 can be lowered, so that the starting circuit 6 can be easily insulated and the starting circuit 6 can be designed. Etc. can be easily performed.

FIG. 9 is a diagram showing a main part of still another embodiment of the present invention. In this example, the arc tube 1-1 of the electrodeless lamp 1
A light-transmissive alumina ring 1-3 is fitted inside the equatorial wall of the arc tube 1 and the luminous tube 1 is formed by the thickness of the alumina ring 1-3.
The thickness of the quartz wall forming -1 is cut. As a result, the capacity of the capacitor formed by the wall of the equator of the arc tube 1-1, that is, the capacity corresponding to C3 in FIG. 8 can be increased, and the high voltage applied from the starting circuit (not shown) at the time of starting is correspondingly increased. As a result, the impedance of the glow discharge path is reduced, and the glow discharge current can be increased in the same manner as described above, with the same effect. Further, in this example, since the alumina ring 1-3 is fitted inside the equatorial wall of the arc tube 1-1, the quartz ring forming the outer wall of the arc tube 1-1 due to the arc discharge generated inside the alumina. It also has the effect of preventing deterioration.

[0022]

As described above, according to the electrodeless lamp lighting device of the present invention, design and adjustment are easy, and stable operation can be performed even with a change with time.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of an electrodeless lighting device of the present invention.

FIG. 2 is a view showing a lighting fixture in which the electrodeless lamp lighting device according to the present invention is housed.

3 is a diagram showing an example of a waveform of a current flowing through a coil L _ST shown in FIG.

FIG. 4 is a diagram showing an example of a waveform of a voltage applied from a starting circuit to the electrodes shown in FIG.

5 is a diagram showing an example of a waveform of a current flowing in the auxiliary discharge tube shown in FIG.

6 is a diagram showing an example of waveforms of apparent power and active power supplied from a starting power supply to the starting circuit shown in FIG.

FIG. 7 is a diagram showing a main part of another embodiment of the present invention.

8 is an equivalent circuit diagram of a glow discharge path of the electrodeless lamp shown in FIG.

FIG. 9 is a diagram showing a main part of still another embodiment of the present invention.

FIG. 10 is a circuit diagram showing an example of a conventional electrodeless lamp lighting device.

[Explanation of symbols]

1 ... Electrodeless lamp 1-2 ... Auxiliary discharge tube 3 ... Electrode 4 ... High frequency power supply generation circuit 5 ... Matching circuit 6 ... Starting circuit 7 ... Starting circuit power supply 8 ... Switch C _ST ... Capacitor L _C ... Excitation coil L _ST ... Coil R _ST … Damping resistance

Claims (4)

[Claims] 1. A high-frequency current generating circuit, an exciting coil to which a high-frequency current generated from the high-frequency current generating circuit is supplied, an electrodeless lamp which is lit by electromagnetic energy generated by the exciting coil, and at the time of starting, A starting circuit for generating a high voltage applied to an auxiliary discharge tube coupled to the arc tube of the electrodeless lamp for a predetermined period, and a power supply circuit for supplying electric power for operating the starting circuit are electrically connected to the high-frequency current generating circuit. An electrodeless lamp lighting device characterized by being provided separately. 2. The starter circuit is composed of a series resonance circuit including a coil and a capacitor, and the coil is the electrodeless lamp so that the electromagnetic energy generated in the coil can be supplied to the electrodeless lamp at the time of starting. The electrodeless lamp lighting device according to claim 1, wherein the electrodeless lamp lighting device is arranged with respect to. 3. The electrodeless lamp lighting device according to claim 1, wherein the outer wall of the electrodeless lamp is made of quartz, and a part of the outer wall is made of a material having a higher dielectric constant than quartz. 4. An illumination comprising an electrodeless lamp, an electrodeless lamp lighting device according to claim 1 or 3 for lighting the electrodeless lamp, and a lighting fixture containing the electrodeless lamp. apparatus.