JPH0997689A - High pressure electric discharge lamp lighting up device and lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable two arc tubes of a dual tube type high pressure electric discharge lamp to be lighted up with the even probability. SOLUTION: This high pressure electric discharge lamp lighting up device is adapted for a dual arc tube type high pressure electric discharge lamp 3 to be started according to a high pressure pulse outputted from a starter 4. A first current limiting element 5 is connected in a two-divided manner to an AC power supply 2 and a power supply line 13 of both positive and negative electrodes, and a second current limiting element 6 is connected in series to the first element 5 at a position nearer to the power supply 2 than the first element 5, then a switch 14 for short-circuiting the second element 6 and the operation can be controlled by a control circuit 15. At the time of power ON, the second element 6 is short-circuited with the operation of switch 14 to lower the impedance in the circuit to thereby make easy the starting of arc tubes 10. Since the first element 5 is divided for the line 13 in this case, the impedance characteristic considered from the tubes 10 is made even between the positive and negative polar characteristics of high pressure pulse, and the probability of alternate starting of the two arc tubes 10 is enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high pressure discharge lamp lighting device and a lighting device for lighting a two-lamp high pressure discharge lamp.

[0002]

2. Description of the Related Art In a high pressure discharge lamp such as a high pressure sodium lamp or a metal halide lamp, the temperature rises during lighting and the internal pressure of the arc tube becomes very high. For this reason, when restarting after the lamp is turned off, it is necessary to wait until the arc tube cools down to some extent and the mercury inside and the encapsulated luminescent metal agglomerate and the internal pressure decreases. For example, in the case of a high-pressure sodium lamp having an external starter, the restart time must be about 1 minute, and in the case of a metal halide lamp, about 10 minutes or more must be waited,
After restarting, you have to wait a few more minutes before the stable lighting state is reached. Therefore, for example, if there is a momentary power failure, the high pressure discharge lamp will not reach full power 10
It takes more than a minute, and it is extremely inconvenient and dangerous when used as road lighting or tunnel lighting.

US Pat. No. 4,287,454 discloses a high-pressure sodium lamp in which two arc tubes are housed in one outer tube. In such a high-pressure sodium lamp, one of the arc tubes emits light during normal operation,
At the time of relighting after a momentary power failure, the other arc tube with low internal pressure emits light. Since the arc tube that emits light later is preheated by the arc tube that was emitting light first and the internal pressure has risen slightly, it reaches a stable lighting state in a few minutes. Therefore,
Such a dual-lamp high-pressure sodium lamp has an extremely short restart time and is suitable for use as road lighting and tunnel lighting.

FIG. 4 is a circuit diagram showing an example of a high pressure discharge lamp lighting circuit 51 for lighting a two-lamp high pressure discharge lamp. FIG. 5 is a waveform diagram of the high-pressure pulse P for starting the high-pressure discharge lamp generated by the high-pressure discharge lamp lighting circuit 51. In the high-pressure discharge lamp lighting circuit 51, the high-pressure discharge lamp 52 has two built-in arc tubes 53 connected in parallel to an AC power supply 54. The arc tubes 53 are provided with starting auxiliary conductors 55 connected to an AC power source 54 in opposite polarities. These starting auxiliary conductors 55 facilitate the starting of each arc tube 53 by the power supply from the AC power supply 54. The high-pressure discharge lamp lighting circuit 51 is provided with a starter 56 that applies a high-voltage pulse P to each arc tube 53 as a start pulse, and a choke coil 57 that limits the lamp current of each arc tube 53 after starting. ing. Further, a power factor correction capacitor 58 and a discharge resistor 59 are connected in parallel to the AC power supply 54.

In the case of such a structure, the high-pressure pulse generated by the starter 56 is applied to the high-pressure discharge lamp 52, and one of the arc tubes 53 emits light. That is, the high-voltage pulse P generated by the starter 56 is superimposed on the AC voltage V from the AC power supply 54 and has either positive or negative polarity, as illustrated in FIG. Therefore, the high-voltage pulse P of one polarity acts as the corresponding start pulse of the arc tube 53 on the side of the auxiliary starting conductor 55, and the high-voltage pulse P of the other polarity acts as the start pulse of the other arc tube 53. This allows
Only one of the arc tubes 53 emits light. After the high pressure discharge lamp 52 is started, the lamp current of the high pressure discharge lamp 52 is limited by the choke coil 57,
Keeps lighting steady.

[0006]

The starting probability of each arc tube 53 in the high pressure discharge lamp 52 is theoretically 50%.
However, in reality, the phenomenon that one of the arc tubes 53 is easier to start occurs. For this reason, the two light-emitting tubes 5
No. 3, the deterioration state is not uniform, and the resulting arc tube 53 is not deteriorated due to the leakage of the rare gas.
It is extremely inconvenient because the starting characteristics and the light emitting characteristics of the above are deteriorated. The reason why the starting characteristics of the arc lamps 53 of the two lamps become non-uniform is that, in addition to variations in the starting characteristics of the high-pressure discharge lamp 52 due to manufacturing errors, the voltage value of the high-voltage pulse P itself is not stable between positive and negative polarities. This is probably because of this (see FIG. 5). Further, such instability of the high-voltage pulse P is caused by the choke coil 57 and is caused by the high-voltage discharge lamp lighting circuit 5.
This is considered to be due to the fact that the impedance characteristics of No. 1 are not uniform on the positive side and the negative side of the high-voltage pulse when viewed from the high-pressure discharge lamp 52.

As disclosed in Japanese Patent Laid-Open No. 5-89845, as shown in FIG. 6, another choke coil 57 is arranged in a symmetrical position to form a double choke coil, and impedance characteristics of the high pressure discharge lamp lighting circuit 51 are measured. An invention is disclosed in which the arc tubes 53 of two lamps are started with equal probability by ensuring uniformity. But,
When the double choke coil structure is used, the impedance in the circuit increases, and it becomes difficult to start the arc tube 53.

In Japanese Patent Laid-Open No. 188080/1994, FIG.
, Two choke coils 57a, 57
b is connected in series, and one choke coil 57b is short-circuited by the switch 61 when the high pressure discharge lamp 52 is started,
An invention is disclosed in which the arc tube 53 is easily started when the power is turned on. However, the circuit of FIG. 7 does not consider starting of a two-lamp high-pressure discharge lamp, and it is unclear how to apply it to a two-lamp high-pressure discharge lamp.

The present invention is a high-pressure discharge lamp lighting circuit applied to a dual-lamp high-pressure discharge lamp, and improves both the uniformity of the starting probabilities of the two-lamp arc tubes and the improvement of the arc tube startability. An object of the present invention is to obtain a high-pressure discharge lamp lighting device and a lighting device that can be used.

[0010]

A high pressure discharge lamp lighting device according to a first aspect of the present invention is connected to an AC power source, and two arc lamps connected in parallel and started by applying a high voltage pulse, and these. And a power supply for applying a high-voltage pulse of alternating current to a high-pressure discharge lamp in which a pair of starting auxiliary conductors, which are arranged close to each other and connected to opposite polarities, are housed in one outer tube; And a first current limiting element that is connected to the positive and negative power feed lines in a divided manner between and to limit the lamp current; and to the first current limiting element on the AC power source side of the first current limiting element. A second current limiting element connected in series; a switch for short-circuiting the second current limiting element; controlling the operation of the switch, and causing the switch to perform the operation of short-circuiting the second current limiting element at least when the power is turned on. Control circuit;
Is provided.

Therefore, when the power is turned on, a high-voltage pulse is generated in the starter, and this high-voltage pulse is superimposed on the AC voltage of the AC power supply and applied to the arc tube and the starting auxiliary conductor. Since the two auxiliary starting conductors have different polarities, a voltage is alternately applied to the auxiliary starting conductor according to the polarity of the high voltage pulse. At this time, since the arc tube on the side of the starting auxiliary conductor to which the voltage is applied is easily started, the arc tubes of the two lamps are started with equal probability. When the power supply for starting the arc tube is turned on, the switch short-circuits the second current limiting element under the control of the control circuit. For this reason, the impedance of the entire current limiting element is lowered and a high voltage pulse having a high voltage value is applied to the high pressure discharge lamp, so that the arc tube easily emits light. Moreover, since the first current limiting element is divided into two, the impedance characteristics seen from the high-pressure discharge lamp are even on the positive electrode side and the negative electrode side of the high-voltage pulse, and the uniform starting probability of the arc tubes of the two lamps is high. Get higher.
As a result, the biased start of one of the arc tubes is prevented, and the life of the high pressure discharge lamp is extended.

Here, as the current limiting element, an inductance component, for example, a choke coil can be used.
The starter may be configured as an external circuit of the high pressure discharge lamp or may be built in the high pressure discharge lamp.

According to a second aspect of the present invention, in the high pressure discharge lamp lighting device according to the first aspect, the second current limiting element and the switch correspond to each of the two divided first current limiting elements. It is divided. Therefore, when there is a time lag in the operation of the switch to short-circuit the second current limiting element in response to turning on the power, the impedance characteristics of the first and second current limiting elements seen from the high pressure discharge lamp are seen even before the operation of the switch. Is even on the positive electrode side and the negative electrode side of the high voltage pulse, and the uniformity of the starting probabilities of the arc tubes of the two lamps is not impaired. Therefore, like the invention according to claim 3, the control circuit according to the invention according to claim 2 detects the presence or absence of the AC voltage applied to the starter by the detector to detect the presence or absence of power-on. Even if configured as a circuit, the uniformity of the starting probabilities of the arc lamps of the two lamps is maintained regardless of the delay of the switch operation, which is unavoidable in such a circuit. Such a control circuit not only has a simple structure, but also can perform dimming control of the high-pressure discharge lamp by using the output of the detector, as in the invention of claim 4, for example. It is possible and has excellent applicability.

[0014] The invention according to claim 5 provides the invention according to claims 1 to 4.
In the high pressure discharge lamp lighting device described above, an element having a low impedance characteristic with respect to high frequencies is connected between the positive and negative power feed lines between the first current limiting element and the second current limiting element. Therefore, the feedback voltage of the high-voltage pulse applied to the high-pressure discharge lamp from the starter passes through the element connected between the first current limiting element and the second current limiting element, and is higher than the second current limiting element. Do not return to the upstream side, that is, the AC power supply side. Therefore, the influence of the unstable factor of the voltage value of the AC power source on the high-voltage pulse applied to the high-pressure discharge lamp is completely eliminated, and the impedance characteristics seen from the high-pressure discharge lamp are more even on the positive side and the negative side of the high-voltage pulse. Therefore, the even start probability of the arc tubes of the two lights becomes higher. Here, for example, a capacitor is used as the element having a low impedance characteristic with respect to a high frequency.

A lighting device according to a sixth aspect of the present invention includes the high pressure discharge lamp lighting device according to any one of the first to fifth aspects; and a high pressure discharge lamp in which two arc tubes are housed in one outer bulb. A lighting fixture main body for holding the discharge lamp lighting device; Therefore, since the arc tubes of the two lamps emit light with equal probability, the life of the high pressure discharge lamp is extended.

[0016]

FIG. 1 shows a first embodiment of the present invention.
A description will be given based on FIG. FIG. 1 is a circuit diagram of a high pressure discharge lamp lighting device. FIG. 2 is a timing chart showing the timing of turning on / off the power source, turning on / off the switch for short-circuiting the second current limiting element, and turning on / off the two arc tubes.

The high-pressure discharge lamp lighting circuit 1 drives a two-lamp high-pressure discharge lamp 3 using a commercial AC power source 2 as a drive source. That is, the starter 4 that applies a high-voltage pulse to the high-pressure discharge lamp 3 when the power is turned on is connected in parallel to the AC power supply 2.
The starter 4 has a well-known structure including a pulse transformer (not shown) as a main component. A ballast 7 including a first choke coil 5 and a second choke coil 6 which are divided into two is connected between the starter 4 and the AC power supply 2. The ballast 7 will be described in detail later. A power factor correction capacitor 8 and a discharge resistor 9 are connected in parallel to the AC power source 2 on the upstream side of the ballast 7.

The high pressure discharge lamp 3 will be described. The high-pressure discharge lamp 3 has the same structure as the high-pressure discharge lamp disclosed in JP-A-5-89845. That is, two arc tubes 10 are provided, and these arc tubes 10 are connected in parallel. Each arc tube 10 has a well-known structure as a high-pressure sodium lamp, and a bulb 10a made of a ceramic tube is filled with sodium, mercury, and xenon gas. In addition, a starting auxiliary conductor 11 for improving the starting property is attached to each of the arc tubes 10 so as to come into contact with and separate from the arc tubes 10 by the action of a bimetal (not shown). The starting auxiliary conductors 11 are
They are electrically connected so that their polarities are different from each other. Each arc tube 10 is hermetically housed in an outer tube 12 made of hard glass or the like. The details of the high-pressure discharge lamp 3 are described in Japanese Patent Application Laid-Open No. 5-89845, and are well known, so the description thereof will be omitted.

The ballast 7 will be described. This ballast 7
Is an inductance component as a current limiting element that functions to stabilize the lighting state of the high pressure discharge lamp 3 after starting.
The first choke coil 5 is divided into two, and the power feeding line 13
Are distributed to the positive electrode side and the negative electrode side. The second choke coil 6 is also divided into two, and is distributed to the positive electrode side and the negative electrode side of the power supply line 13 on the side of the AC power supply 2 with respect to the first choke coil 5. A pair of switches 14 that short-circuit the second choke coil 6 are connected in parallel to the second choke coil 6. The switch 14 is configured so that its operation is simultaneously controlled by the control circuit 15 connected to the AC power supply 2. The control circuit 15 has a detector 16 for detecting a lamp current, and has a structure for performing operation control of the switch 14 and dimming control of the high pressure discharge lamp 3.

A high frequency bypass path 17 is provided in the ballast 7.
Is provided. That is, the positive and negative power supply lines 13
Between the first choke coil 5 and the second choke coil 6
Bypass capacitor 18 that bypasses high frequency between
Are connected in parallel, so that the high frequency bypass path 17
Are formed. The bypass capacitor 18 functions as an element having a low impedance characteristic with respect to high frequencies.

In such a structure, the high-voltage pulse generated by the starter 4 is superimposed on the AC voltage of the AC power supply 2 and applied to the arc tubes 10 and the starting auxiliary conductor 11 of the two lamps.
At this time, since the starting auxiliary conductors 11 have different polarities,
A high voltage pulse having a positive or negative polarity is alternately applied to the two starting auxiliary conductors 11. Two-light arc tube 1
0 is easier to start when it is closer to the starting auxiliary conductor 11 to which the high-voltage pulse is applied, so one of the arc tubes 10 that is easier to start
Only selectively start and light up. After one of the arc tubes 10 is lit, the choke coils 5 and 6 are lit.
The rise of the lamp current of 0 is limited, and the high-pressure discharge lamp 3 maintains stable lighting. At this time, the fluctuation of the lamp current is detected by the detector 16, and the control circuit 15 performs the dimming control by the feedback control based on the detection result to maintain the lighting state of the high pressure discharge lamp 3 at a constant level.

The starting of the high pressure discharge lamp 3 will be described in more detail. When the power supply for starting the arc tube 3 is turned on, the control circuit 15 detects the power supply based on the current detection of the detector 16. As a result, the control circuit 15 controls the operation of the switch 14, and by this control, the two switches 14 short-circuit the second choke coil 6 divided into two. Therefore, the impedance with respect to the high-voltage pulse is lowered, and a high-voltage pulse having a high voltage value is applied to the high-pressure discharge lamp 3, and the arc tube 10 is easily activated. Moreover, since the first choke coil 5 is divided into two, the impedance characteristics seen from the high-pressure discharge lamp 3 become uniform on the positive electrode side and the negative electrode side of the high-voltage pulse, and the arc tubes 10 of the two lamps start up evenly. The probability of doing so is higher. As a result, the biased start of one of the arc tubes 10 is prevented, and the life of the high pressure discharge lamp 3 is extended.

When the high-voltage pulse is output from the starter 4, the bypass capacitor 18 forms the high-frequency bypass path 17. That is, bypass capacitor 1
Since 8 has a low impedance characteristic with respect to a high frequency, a high frequency high voltage pulse bypasses the AC power supply 2 and the like through the bypass capacitor 18. Therefore, regardless of the polarity of the high-voltage pulse, the paths are equivalent in the high-pressure discharge lamp lighting circuit 1, and the voltage value of the high-voltage pulse may fluctuate in the high-voltage discharge lamp lighting circuit 1 depending on the positive and negative polarities. Absent. Moreover, since the AC power supply 2 is bypassed, the unstable element relating to the voltage value of the AC power supply 2 does not affect the high-voltage pulse at all. Therefore, the probability that the two arc tubes 10 will start at an equal rate in response to the switch being turned on increases.

Here, as shown in the timing chart of FIG. 2, there is a time lag in the operation in which the switch 14 short-circuits the second choke coil 6 in response to power-on. Therefore, the high voltage pulse is returned to the second choke coil 6 immediately after the power is turned on. On the other hand, in the present embodiment, since the second choke coil 6 is also divided into two, even if the high-voltage pulse returns to the second choke coil 6 immediately after the power is turned on, the high-pressure discharge lamp 3 outputs The uniformity of the seen impedance characteristics between the positive electrode side and the negative electrode side of the power supply line 13 is not impaired.

Further, as shown in the timing chart of FIG. 2, the switch 14 is turned off and the function of the second choke coil 6 is restored after the start of one arc tube 10.
As a result, the impedance in the inductance component formed by the first and second choke coils 5 and 6 is increased, and the function of the ballast 6 is fulfilled with respect to the arc tube 10 which is being lit.

In practice, the starter 4 and the like may be built in the high pressure discharge lamp 3. That is, the present invention can be implemented as a known high-pressure discharge lamp having a built-in starter that generates a high-voltage pulse by opening a start switch made of bimetal.

A second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a vertical side view of the lighting device. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The lighting device of this embodiment is road lighting. A flat casing-shaped main body case 31 is provided, and a holding portion 32 that detachably supports the high pressure discharge lamp 3 and that houses the high pressure discharge lamp lighting circuit 1 is attached to the main body case 31. The high pressure discharge lamp lighting circuit 1 uses the first embodiment described above. A light projecting window 33 is formed in the main body case 31 at a position facing the high pressure discharge lamp 3 supported by the holding portion 32, and a transparent glass 34 is fitted into the light projecting window 33. Body case 31
Are connected and supported on a pole (not shown) installed on the road via a connecting body 35. The power supply line for the high pressure discharge lamp lighting circuit 1 is housed in the coupling body 35 and the pole. The main body case 31, the holding portion 32, and the glass 34 form a main body of the lighting fixture.

In the illuminating device having such a structure, the high-pressure discharge lamp 3 has a long life because the two light-emitting tubes 10 are started with equal probability. Therefore, maintenance is easy.

[0030]

According to the first aspect of the present invention, there is provided a high-pressure discharge lamp lighting device applied to a two-lamp high-pressure discharge lamp which is started by a high-pressure pulse output from a starter. Since the current limiting element of 2 is short-circuited by the operation of the switch and only the first current limiting element divided in two is made to function, the impedance in the circuit is lowered at the time of starting the arc tube to facilitate starting the arc tube. At this time, the impedance characteristic viewed from the arc tube can be made uniform between the positive and negative polarities of the high voltage pulse by the first current limiting element divided into two, and the probability that the arc tubes are alternately started can be increased. it can. As a result, the demand for instantaneous lighting of the high-pressure discharge lamp and the demand for longer life of the high-pressure discharge lamp can be balanced at a high level.

According to the second aspect of the present invention, the second current limiting element and the switch are also divided into two parts corresponding to the first current limiting element. If there is a time lag in the operation of short-circuiting, the impedance characteristics due to the first and second current limiting elements seen from the high-pressure discharge lamp can be made uniform between the positive and negative polarities of the high-voltage pulse even before the operation of the switch, The uniformity of the starting probabilities of the two arc tubes can be further increased.

Therefore, on the premise of the invention according to claim 2, as in the invention according to claim 3, the presence or absence of the AC voltage applied to the starter is detected by the detector to detect the presence or absence of power-on. Even if such a circuit is used as the control circuit, the uniformity of the starting probabilities of the arc tubes of the two lamps can be favorably maintained regardless of the delay of the switch operation, which is unavoidable in such a circuit. Therefore, as a control circuit,
A circuit that can be easily configured can be used. Further, if the control circuit in the invention of claim 3 is used, it is possible to easily perform the dimming control of the high pressure discharge lamp by utilizing the output of the detector as in the invention of claim 4. It is possible to make the device excellent in applicability.

According to a fifth aspect of the present invention, an element having a low impedance characteristic with respect to a high frequency is located between the first current limiting element and the second current limiting element and is connected between the positive and negative pole feed lines. Therefore, the impedance characteristic viewed from the arc tube can be made more uniform between the positive and negative polarities of the high voltage pulse, and the probability that the arc tubes are alternately started can be further increased.

A lighting device according to a sixth aspect of the present invention is a high pressure discharge lamp lighting device according to any one of the first to fifth aspects, in which a high pressure discharge lamp in which two light emitting tubes are housed in one outer tube is mounted. Since it is provided, the light emitting tubes of the two lamps can be made to emit light with equal probability and their life can be extended.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a high pressure discharge lamp lighting device showing a first embodiment of the present invention.

FIG. 2 is a timing chart showing on / off of a power source, on / off of a switch for short-circuiting a second current limiting element, and lighting / non-lighting of two arc tubes.

FIG. 3 is a vertical cross-sectional side view of an illumination device showing a second embodiment of the present invention.

FIG. 4 is a circuit diagram showing an example of a conventional high pressure discharge lamp lighting device.

FIG. 5 is a waveform diagram showing a waveform of a high voltage pulse applied to the high pressure discharge lamp.

FIG. 6 is a circuit diagram showing another example of a conventional high pressure discharge lamp lighting device including an improvement regarding a current limiting element.

FIG. 7 is a circuit diagram showing still another example of a conventional high pressure discharge lamp lighting device including an improvement regarding a current limiting element.

[Explanation of symbols]

2 AC power supply 3 High-pressure discharge lamp 4 Starter 5 First current limiting element (inductance component) 6 Second current limiting element (inductance component) 10 Arc tube 11 Starting auxiliary conductor 12 Outer tube 13 Power supply line 14 Switch 15 Control circuit 16 Detector 18 Element having low impedance characteristic for high frequency 31, 32, 34 Lighting fixture main body

Claims (6)

[Claims] 1. An arc tube of two lamps connected in parallel to each other, which are connected to an AC power source and started by applying a high-voltage pulse, and a pair of arc tubes which are arranged in proximity to each of the arc tubes and are connected to each other in opposite polarities. A starter for applying a high-voltage pulse of alternating current to a high-pressure discharge lamp having a starting auxiliary conductor housed in a single outer tube; and divided into two positive and negative power supply lines between the starter and the alternating-current power source A first current limiting element for limiting a lamp current; a second current limiting element connected in series to the first current limiting element on the side of the AC power source with respect to the first current limiting element; A switch that short-circuits the second current limiting element; and a control circuit that controls the operation of the switch and causes the switch to perform the operation of short-circuiting the second current limiting element at least when the power is turned on. High pressure discharge lamp lighting device . 2. The high pressure discharge lamp according to claim 1, wherein the second current limiting element and the switch are divided into two parts corresponding to each of the two divided first current limiting elements. Lighting device. 3. The control circuit comprises a detector for detecting the presence / absence of an AC voltage applied to the starter, and the presence / absence of power-on is detected by the output of the detector. High pressure discharge lamp lighting device. 4. The control circuit controls the dimming of the high pressure discharge lamp by using the output of the detector.
The high pressure discharge lamp lighting device described. 5. An element having a low impedance characteristic with respect to a high frequency is connected between the positive and negative power feed lines between the first current limiting element and the second current limiting element. The high pressure discharge lamp lighting device according to any one of 1 to 4. 6. A high pressure discharge lamp lighting device according to claim 1, and a lighting device for holding the high pressure discharge lamp lighting device together with a high pressure discharge lamp in which two light emitting tubes are housed in one outer tube. An illuminating device comprising: a main body of a fixture.