JP4316180B2 - High pressure discharge lamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a high pressure discharge lamp.
[0002]
[Prior art]
  In recent years, high-pressure discharge lamps, such as high-pressure sodium lamps, are more than twice as efficient as high-pressure mercury lamps. It is spreading for indoor lighting.
[0003]
  In general, a high-pressure sodium lamp has an arc tube in which an electrode is provided at both ends in an outer tube and sodium amalgam and xenon are sealed inside, and a starting device connected in parallel to the arc tube. In addition, a starting auxiliary conductor for suppressing an increase in starting voltage is attached to the outer surface of the arc tube. If a specific potential is applied to this starting auxiliary conductor during steady lighting, the sodium enclosed in the arc tube will cause the sodium to disappear from the arc tube. Therefore, the starting auxiliary conductor is electrically cut off during steady lighting. Maintained at or near the closed state.
[0004]
  Among high-pressure sodium lamps, in particular, a high-pressure sodium lamp (hereinafter referred to as a “high-pressure xenon-type high-pressure sodium lamp”) in which the sealed pressure of xenon enclosed in the arc tube is 26 kPa to 45 kPa is highly efficient. Since it is possible to prevent the electron emitting material applied to one electrode from being scattered by ion bombardment from the other electrode at the time of starting, it has excellent life characteristics and has a life time of 12000 hours (rated life time). ) The above has been realized.
[0005]
  Such high-pressure xenon-type high-pressure sodium lamps can be replaced with existing high-pressure mercury lamps and are low-cost, so they are generally equipped with a copper-iron-type reactance ballast for high-pressure mercury lamps. Used in combination with a circuit.
[0006]
  Next, two types of starting devices conventionally used in such a high-pressure sodium lamp will be described.
[0007]
  As shown in FIG. 5, the first type of starting device 30 is closed at room temperature and is made of bimetal, a current interrupting thermal responsive switch 14, and limits the current and opens the current interrupting thermal responsive switch 14. A series circuit with a heating resistor 15 (Japanese Patent Laid-Open No. 59-850). One end of the starting auxiliary conductor 8 attached to the outer surface of the arc tube 6 is closed at room temperature and connected to one electrode (not shown) of the arc tube 6 via a thermally responsive switch 31 made of bimetal. .
[0008]
  Next, a starting device for lighting a high-pressure xenon-type high-pressure sodium lamp 32 incorporating this type of starting device 30 in combination with a lighting circuit 18 equipped with a copper-iron-type reactance stabilizer 17 for a high-pressure mercury lamp. The operation of 30 will be described.
[0009]
  When the AC power supply voltage 19 is applied to the high-pressure sodium lamp 32, the current interrupting thermal responsive switch 14 is opened by the heating resistor 15. The current is cut off by this opening operation, and a high voltage pulse voltage of 3 kV to 4 kV is induced in the copper iron type reactance stabilizer 17. The arc tube 6 is started by the induced high voltage pulse voltage and the effect of lowering the starting voltage by the starting auxiliary conductor 8.
[0010]
  Then, immediately after starting the arc tube 6, the opening / closing operation of the current interrupting thermal response switch 14 is stopped. Next, 1 to 3 minutes after the start of the start, the current interrupting heat responsive switch 14 is opened by the heat radiation from the arc tube 6, and the starter 30 is released from the lighting circuit 18. On the other hand, the heat responsive switch 31 is opened 5 to 7 minutes after the start of the start due to heat radiation from the arc tube 6, and the start-up auxiliary conductor 8 shifts to a state where it is electrically cut off.
[0011]
  Here, in the operation of the starter 30, the current interrupting heat responsive switch 14 takes 1 to 3 minutes from the start of starting the arc tube 6 to the open state, whereas the heat responsive switch 31 is The time from the start of the arc tube 6 to the open state is set to be as long as 5 to 7 minutes. The reason is as follows. In other words, when the lamp is restarted, the return time from the open state to the closed state of the thermal response switch 31 is set to be shorter than the return time of the thermal interrupt switch 14 for interrupting the current. Accordingly, when the current interrupting thermal response switch 14 performs an opening / closing operation at the time of restarting the lamp, the thermal response switch 31 is always in the closed state, and the starting auxiliary conductor 8 functions normally.
[0012]
  Next, as shown in FIG. 6, the second type of starting device 33 is closed at room temperature, and the starter opening thermal responsive switch 21 made of bimetal, the current limiting resistor 22 made of tungsten filament, A pulse-stopping thermally responsive switch 34 made of bimetal, a non-linear ceramic capacitor element 23 (NCC element) for interrupting current, and a voltage detection type switching element 25 made up of a bidirectional semiconductor switching element are sequentially connected. A series circuit, a heating resistor 35 connected in parallel to the series circuit of the pulse stop thermal responsive switch 34, the NCC element 23, and the voltage detection type switching element 25, and a pulse stop thermal responsive switch 34 connected in parallel. And a bypass resistor 36 for preventing degradation of the NCC element 23 due to pyroelectric current, The oscillation phase of the high-voltage pulses which are connected in parallel to the detection switching element 25 and a control resistor 37 to stabilize.
[0013]
  One end of the starting auxiliary conductor 8 is connected to one electrode (not shown) of the arc tube 6 via a small-capacitance capacitor 38 of 1 nF, for example.
[0014]
  Note that the pulse stop thermal responsive switch 34 is opened by the heating resistor 35 when the lamp is not lit, and has a function of stopping the pulse oscillation.
[0015]
  Next, as shown in FIG. 6, when a high-pressure xenon-type high-pressure sodium lamp 39 incorporating this type of starting device 33 is lit in combination with a lighting circuit 18 having a copper iron-type reactance stabilizer 17. The operation of the starter 33 will be described.
[0016]
  When the AC power supply voltage 19 is applied to the high-pressure sodium lamp 39, a high-voltage pulse voltage of about 2 kV is induced in the reactance stabilizer 17 by the current switching operation of the NCC element 23 every half cycle. The arc tube 6 is started by the induced high voltage pulse voltage and the effect of lowering the starting voltage by the starting auxiliary conductor 8.
[0017]
  Immediately after starting the arc tube 6, the voltage applied to the NCC element 23 decreases, the current switching operation of the NCC element 23 becomes impossible, and the high voltage pulse voltage oscillation stops.
[0018]
  Next, the heat responsive switch 21 for opening the starting device is opened by the heat radiation from the arc tube 6, and the starting device 33 is released from the lighting circuit 18. This open state is maintained during steady lighting. On the other hand, the starting auxiliary conductor 8 is maintained in substantially the same state as when electrically interrupted by the small-capacitance capacitor 38 during steady lighting.
[0019]
[Problems to be solved by the invention]
  However, in such a conventional high-pressure xenon type high-pressure sodium lamp with a built-in starter, after the lighting of the rated life time exceeding 12000 hours, for example, 16000 hours, the auxiliary starter conductor 8 is provided on the outer surface of the arc tube 6. In the vicinity, black spots, which are traces of disappearance of sodium sealed in the arc tube 6, are observed, and the emission color change (decrease in color temperature) due to the disappearance of sodium and disappearance due to the increase in lamp voltage are observed. There was a problem that occurred.
[0020]
  This high-pressure xenon-type high-pressure sodium lamp with a built-in starter has relatively stable life characteristics, and the actual life time of the lamp in the market almost exceeds the rated value. Therefore, in the high-pressure xenon-type high-pressure sodium lamp with a built-in starter, the lamp failure due to the disappearance of sodium is a serious problem in terms of market quality.
[0021]
  The present invention has been made to solve such a problem, and in particular, in a high-pressure discharge lamp having a long lamp life, it is possible to suppress the disappearance of sodium sealed in the arc tube, and the emission color of the lamp. An object of the present invention is to provide a high-pressure discharge lamp capable of preventing the occurrence of extinction due to the change of the lamp or the increase of the lamp voltage.
[0022]
[Means for Solving the Problems]
  A high-pressure discharge lamp according to the present invention includes an arc tube having electrodes at both ends, a starting device connected in parallel to the arc tube, and a starting auxiliary conductor attached to an outer surface of the arc tube.,The starting device comprises:A series circuit of first and second shut-off thermal responsive switches made of bimetal closed at room temperature and a heating resistor provided close to the first and second shut-off thermal responsive switches at substantially the same distance One end of the auxiliary starting conductor is connected between the first thermal cutoff switch and the second thermal cutoff switch, and when a current flows through the series circuit, The heating resistor generates heat, and by the heat transfer, the first shut-off thermal responsive switch or the second shut-off thermal responsive switch is opened to shut off the conduction of the series circuit, and then the arc tube After starting, the first thermal shutoff switch and the second thermal shutoff switch are opened by adding heat from the arc tube to the remaining heat due to heat transfer from the heating resistor, Electrically connect the starting auxiliary conductor To cross, characterized in that.
  Further, the high pressure discharge lamp of the present invention includes an arc tube having electrodes at both ends, a starting device connected in parallel to the arc tube, and a starting auxiliary conductor attached to the outer surface of the arc tube.,The starting device is provided in the proximity of the thermal shutoff switch for shutting off and the thermal auxiliary switch for shutting off for shifting the starter auxiliary conductor to an electrically shut off state after the arc tube is started up. And a heating resistor for opening the thermal shut-off switch for shut-off, comprising the non-linear ceramic capacitor element and the thermal shut-off switch for shut-off and voltage detection both having a pulse stop function The heating resistor is connected in parallel to the series circuit of the non-linear ceramic capacitor element, the shut-off thermal responsive switch, and the voltage sensing switching element. The one end of the starting auxiliary conductor is connected between the thermal response switch for interruption and the voltage detection type switching element.
[0023]
  Thereby, after the start of the arc tube, since the thermal response switch for cutoff is heated by the heating resistor, the thermal response switch for cutoff can be quickly opened, and thus the startup auxiliary conductor is electrically disconnected. The state can be quickly transferred. As a result, particularly in a high-pressure sodium lamp having a long life exceeding the rated life of 12000 hours, it is possible to suppress the disappearance of sodium sealed in the arc tube even after the lighting elapsed time exceeding the rated life. Therefore, it is possible to prevent the lamp emission color from being changed and the lamp voltage from being extinguished.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0025]
  The starter built-in type high-pressure sodium lamp having a rated power of 360 W according to the first embodiment of the present invention has one end closed and the other end sealed by a stem 1, as shown in FIG. For example, an outer tube 2 made of hard glass, an E-shaped base 3 attached to the end of the outer tube 2 on the stem 1 side, and two long and short stems built in the outer tube 2 and led out from the stem 1 The arc tube 6 connected and held to the wires 4 and 5, the starter 7 which is also built in the outer tube 2 and connected in parallel with the arc tube 6, and is wound along the outer surface of the arc tube 6 And a starting auxiliary conductor 8 made of molybdenum and attached thereto.
[0026]
  The outer tube 2 is sealed in a vacuum state or an inert gas.
[0027]
  As shown in FIG. 2, the envelope 9 of the arc tube 6 is made of polycrystalline alumina ceramic and has a cylindrical shape with an inner diameter of 7.4 mm and a wall thickness of 0.8 mm. A niobium tube 11 having a tungsten electrode 10 connected to the end is hermetically sealed with ceramic cement 12 at both ends of the arc tube 6. The electrode 10 is coated with an electron emitting substance (not shown). The distance between the electrodes 10 is 86 mm. Further, in the arc tube 6, 22 mg of sodium amalgam (15% by weight of sodium) and 30 kPa of xenon are sealed.
[0028]
  As shown in FIG. 3, the starter 7 is a shutoff thermally responsive switch made of bimetal that is closed at room temperature and moves the auxiliary starter conductor 8 to an electrically disconnected state after the arc tube 6 is started. 13, 14When, ElectricIt has a series circuit with a heating resistor 15 for restricting the flow and opening the two thermally responsive switches 13,14.Here, the thermal responsive switches 13 and 14 for interruption also serve as thermal responsive switches for electric current interruption.
[0029]
  twoFor blockingThe thermally responsive switches 13 and 14 are both disposed close to the heating resistor 15 in the vicinity of, for example, about 3 mm to 10 mm.
[0030]
  The heating resistor 15 is made of a tungsten filament coil wound around an alumina ceramic member.
[0031]
  One end of the starting auxiliary conductor 8OneAn intermediate point (point a in FIG. 3) between the thermal response switch 14 for shutoff and the heating resistor 15, orThe otherIt is connected to an intermediate point (point b in FIG. 3) between the thermal activation switch 13 for blocking and the heating resistor 15 and the other end is open.
[0032]
  Next, as shown in FIG. 3, such a starter built-in type high-pressure sodium lamp 16 is combined with a lighting circuit 18 having a copper-iron-type reactance stabilizer 17 for a high-pressure mercury lamp. 7 will be described.
[0033]
  When the AC power supply voltage 19 is applied to the high-pressure sodium lamp 16, the thermal activation switch 13 for shutoff orIs shieldedThe disconnection heat responsive switch 14 is opened by the heating resistor 15. The current is cut off by this opening operation, and a high voltage pulse voltage of 3 kV to 4 kV is induced in the copper iron type reactance stabilizer 17. The arc tube 6 is started by the induced high voltage pulse voltage and the effect of lowering the starting voltage by the starting auxiliary conductor 8.
[0034]
  In general, the arc tube 6 is a thermal response switch 13 for blocking orIs shieldedIt is started by the opening and closing operation of the disconnection heat responsive switch 14 1 to 3 times.
[0035]
  Then, immediately after starting the arc tube 6,For blockingThe open / close operation of the heat responsive switches 13, 14 is stopped,For blockingBoth the thermally responsive switches 13 and 14 are closed. EachFor blockingThe temperature of the thermally responsive switches 13 and 14 is increased by heating by the heating resistor 15 during the opening / closing operation.
[0036]
  1 to 3 minutes after startingFor blockingThe heat responsive switches 13 and 14 are opened due to heat radiation from the arc tube 6. By this opening operation, the starting device 7 is released from the lighting circuit 18, and the starting auxiliary conductor 8 shifts to a state where it is electrically cut off. And this state is maintained at the time of steady lighting.
[0037]
  Next, the operational effects of the starter built-in type high-pressure sodium lamp (hereinafter referred to as “the product A of the present invention”) having a rated power of 360 W according to the first embodiment of the present invention were examined.
[0038]
  First, 100 products A of the present invention were produced, and each produced lamp was lit in combination with a lighting circuit 18 equipped with a copper iron-type reactance stabilizer 17 for a high-pressure mercury lamp, and a life test was conducted. Then, the presence or absence of a change in emission color after lighting for 16000 hours and the presence or absence of extinction due to an increase in lamp voltage were examined.
[0039]
  Further, instead of the starter 7, a starter built-in type high-pressure sodium lamp having a rated power of 360 W having the same configuration as the product A of the present invention except that the conventional starter shown in FIG. (Hereinafter referred to as “conventional product A”), a life test was conducted under the same conditions as the product A of the present invention, and the presence or absence of a change in emission color after lighting for 16000 hours and the occurrence of extinction due to an increase in lamp voltage were examined. It was.
[0040]
  The life test was repeated for one cycle of lighting for 2.5 hours and turning off for 0.5 hours.
[0041]
  As a result, in the product A of the present invention, the sodium disappearance phenomenon is not observed even after 16000 hours of lighting exceeding 12000 hours which is the rated life time of the product A of the present invention, and it disappears due to a change in luminescent color or a rise in lamp voltage. It was found that neither occurred.
[0042]
  On the other hand, in the conventional product A, the sodium disappearance phenomenon was not observed at all within the rated life time of 12000 hours, but after 16000 hours of lighting, 7 out of 100 were the arc tube 6 A special black spot, which is a trace of sodium disappearance, is observed in the vicinity of the starting auxiliary conductor 8 on the outer surface of the lamp, the emission color changes from orange to pink, and the lamp voltage increases by 20 V or more. And disappearance occurred. Actually, when the amount of sodium disappearance in the conventional product A was examined, it was found that 2 mg to 3 mg had disappeared from the initial amount (22 mg) encapsulated.
[0043]
  The reason for this result is considered as follows.
[0044]
  In the product A of the present invention, the heat-resisting switch 15 is used for the heating resistor 15 to shift the starting auxiliary conductor 8 to a state where it is electrically cut off., 14 eitherSince they are arranged close to each other, after starting the arc tube 6, the thermal response switch 13 for shut-off is used., 14Is quickly heated by the heating resistor 15, and the heat responsive switch 13, 14It is considered that this was because the opening time of 1 to 3 minutes was as early as 1 minute to 3 minutes, and thus the auxiliary starting conductor 8 could be promptly shifted to a state where it was electrically cut off.
[0045]
  On the other hand, in the conventional product A, the open time of the thermal activation switch for interruption after starting the arc tube 6 is as long as 5 to 7 minutes, and during this time, a specific potential is applied to the starting auxiliary conductor 8. It is thought that sodium disappearance occurred.
[0046]
  As described above, according to the configuration of the high-pressure sodium lamp according to the first embodiment of the present invention, the thermal resistance for interruption for causing the heating resistor 15 to shift the starting auxiliary conductor 8 to the electrically interrupted state. Switch 13, 14Since the arc tube 6 is started, the thermal response switch 13 for shutoff is started after the arc tube 6 is started., 14Is quickly heated by the heating resistor 15, and the heat responsive switch 13, 14The opening time is 1 minute to 3 minutes, so that the auxiliary starting conductor 8 can be promptly shifted to a state where it is electrically cut off. As a result, particularly in a high-pressure sodium lamp having a long life exceeding the rated life of 12000 hours, it is possible to suppress the disappearance of sodium sealed in the arc tube 6 even after the lighting elapsed time exceeding the rated life. It is possible to prevent the lamp emission color from changing due to the disappearance of the lamp and the occurrence of the extinction due to the increase of the lamp voltage.
[0047]
  Note that one end of the starting auxiliary conductor 8 isOneThe midpoint between the thermal response switch 14 for shutoff and the heating resistor 15, orThe otherSince it is connected to the intermediate point between the thermal response switch 13 for shutdown and the resistor 15 for heating, the thermal response switch 13 for shutdown, 14Is the starter 7OpeningSince it also functions as a closed switch, when restarting,OneThermally activated switch for shutoffChiReturn timeThe otherThermally activated switch for shutoffChiIt is not necessary to set earlier than the recovery time.
[0048]
  Next, a high-pressure sodium lamp with a built-in starter having a rated power of 360 W according to the second embodiment of the present invention is the same as that of the present invention except that the structure of the starter 20 is different as shown in FIG. It has the same configuration as the high-pressure sodium lamp with a built-in starter having a rated power of 360 W according to the first embodiment.
[0049]
  The starter 20 is closed at room temperature, and is a thermal activation switch 21 for opening the starter made of bimetal, a current limiting resistor 22 made of tungsten filament, a non-linear ceramic capacitor element 23 (NCC element) for current interruption, closed at room temperature In addition, a thermal circuit switch 24 that is made of a bimetal having a pulse stop function and a voltage detection type switching element 25 that is made of a bidirectional semiconductor switching element are sequentially connected, and the NCC element 23 and the cutoff circuit A heating resistor 26 connected in parallel to the series circuit of the thermal responsive switch 24 and the voltage detection type switching element 25 and disposed close to the thermal responsive switch 24 for shutdown, the thermal responsive switch 24 for cutoff and the voltage A resistor 27 connected in parallel to a series circuit with the detection type switching element 25; To have.
[0050]
  In the starting device 20, the connection position between the thermal response switch for interruption 24 and the voltage detection type switching element 25 may be switched.
[0051]
  The pulse stop function of the thermal responsive switch 24 for shutoff is a function to stop the pulse oscillation by quickly opening the thermal responsive switch 24 by the heating resistor 26 when the lamp is not lit.
[0052]
  The resistor 27 is for stabilizing the oscillation phase of the high-voltage pulse voltage and preventing the NCC element 23 from being deteriorated by the pyroelectric current.
[0053]
  When the xenon in the arc tube 6 leaks into the outer tube 2, the tungsten electrode 28 generates an arc discharge with the current limiting resistor 22 and disconnects the current limiting resistor 22 to generate a pulse oscillation. It has a function to stop the operation.
[0054]
  One end of the starting auxiliary conductor 8 is connected to an intermediate point (point c in FIG. 4) between the thermal activation switch 24 for interruption and the voltage detection type switching element 25.
[0055]
  Next, the operation of the starter 20 when such a high-pressure sodium lamp 29 with a built-in starter is combined with the lighting circuit 18 equipped with the copper iron type reactance stabilizer 17 for the high-pressure mercury lamp will be described.
[0056]
  When the AC power supply voltage 19 is applied to the high-pressure sodium lamp 29, a high-voltage pulse voltage of about 2 kV is induced in the reactance stabilizer 17 by the current switching operation of the NCC element 23 every half cycle. The arc tube 6 is started by the induced high voltage pulse voltage and the effect of lowering the starting voltage by the starting auxiliary conductor 8.
[0057]
  Immediately after starting the arc tube 6, the voltage applied to the NCC element 23 decreases, the current switching operation of the NCC element 23 becomes impossible, and the high voltage pulse voltage oscillation stops.
[0058]
  The shut-off heat responsive switch 24 continues to be heated by the heating resistor 26 until the starter opening heat responsive switch 21 is opened, and is further heated by the heat radiation from the arc tube 6 for 1 minute after starting. Open after 3 minutes. By this opening operation, the starting auxiliary conductor 8 shifts to a state where it is electrically cut off. At this time, the voltage detection type switching element 25 functions as an insulating element that opens the starting auxiliary conductor 8 from the lighting circuit.
[0059]
  In addition, after starting the arc tube 6, the starter opening thermal responsive switch 21 is opened due to heat radiation from the arc tube 6, and the starter 20 is released from the lighting circuit 18. And this state is maintained at the time of steady lighting.
[0060]
  The opening time of the starter opening thermal responsive switch 21 is set to 2 to 3 minutes in the present embodiment, but need not be set to a specific range.
[0061]
  Further, when the arc tube 6 is restarted, the return time of the starter opening thermal response switch 21 is set longer than the return time of the shut-off thermal response switch 24. This is because if the return time of the starter opening thermal responsive switch 21 is shorter than the return time of the shut-off thermal responsive switch 24, a current flows through the heating resistor 26, so that the thermal responsive switch 24 cannot be recovered due to its heat dissipation. Because there are cases.
[0062]
  Next, the effect of the high-pressure sodium lamp (hereinafter referred to as “the product B of the present invention”) having a rated power of 360 W according to the second embodiment of the present invention and having a built-in starter was examined.
[0063]
  First, 100 products B of the present invention were produced, and each produced lamp was lit in combination with a lighting circuit 18 equipped with a copper iron type reactance stabilizer 17 for a high-pressure mercury lamp, and a life test was conducted. Then, the presence or absence of a change in emission color after lighting for 16000 hours and the presence or absence of extinction due to an increase in lamp voltage were examined.
[0064]
  Further, instead of the starter 20, a starter built-in type high-pressure sodium lamp having a rated power of 360 W having the same configuration as the product B of the present invention except that the conventional starter shown in FIG. (Hereinafter referred to as “conventional product B”), a life test was conducted under the same conditions as the product B of the present invention, and the presence or absence of a change in emission color after 16000 hours of lighting and the occurrence of extinction due to an increase in lamp voltage were examined. It was.
[0065]
  As a result, in the product B of the present invention, no sodium disappearance phenomenon was observed even after 16,000 hours of lighting exceeding the rated life time of 12000 hours, and disappearance due to a change in luminescent color or an increase in lamp voltage occurred. I found out that I would not.
[0066]
  On the other hand, in the conventional product B, no sodium disappearance phenomenon was observed within the rated life time of 12000 hours, but after 16000 hours of lighting, 10 out of 100 were the arc tube 6. A special black spot, which is a trace of sodium disappearance, is observed in the vicinity of the starting auxiliary conductor 8 on the outer surface of the lamp, the emission color changes from orange to pink, and the lamp voltage rises by 20 V or more. Then disappeared. Actually, when the amount of sodium disappearance in the conventional product B was examined, it was found that 2 mg to 3 mg had disappeared from the initial amount (22 mg) encapsulated.
[0067]
  The reason for this result is considered as follows.
[0068]
  In the product B of the present invention, the thermal activation switch 24 for interruption for shifting the starting auxiliary conductor 8 to the electrically insulated state, and the heating resistor 26 disposed in the vicinity of the thermal activation switch 24 for interruption. In addition, after starting the arc tube 6, the shut-off heat responsive switch 24 is heated by the heating resistor 26, and the heat radiation from the arc tube 6 is also added, so that it is quickly opened for 1 to 3 minutes. Therefore, it is considered that this is because the starting auxiliary conductor 8 can be promptly shifted to a state where it is electrically cut off.
[0069]
  On the other hand, in the conventional product B, since one end of the starting auxiliary conductor 8 is connected to the starting device via a small-capacitance capacitor, the starting auxiliary conductor 8 is completely cut off electrically even during steady lighting. It is thought that sodium disappearance occurred.
[0070]
  As described above, according to the configuration of the high-pressure sodium lamp according to the second embodiment of the present invention, the high-pressure sodium lamp is provided to shift the start-up auxiliary conductor 8 to substantially the same state as in the conventional case. It is no longer necessary to use the small-capacitance capacitor that has been used, and instead, a thermal responsive switch 24 for shifting the auxiliary auxiliary conductor 8 to an electrically disconnected state and a thermal responsive switch 24 for the thermal shutdown are arranged in the vicinity. In addition, after the start-up of the arc tube 6 is started, the thermal response switch 24 for shutting off is heated by the heating resistor 26, and further, the heat radiation of the arc tube 6 is added, so that 1 to 3 minutes. Since the starting auxiliary conductor 8 is opened quickly, the start auxiliary conductor 8 can be quickly shifted to the electrically disconnected state. As a result, particularly in a high-pressure sodium lamp having a long life exceeding the rated life of 12000 hours, it is possible to suppress the disappearance of sodium sealed in the arc tube 6 even after the lighting elapsed time exceeding the rated life. It is possible to prevent the lamp emission color from changing due to the disappearance of the lamp and the occurrence of the extinction due to the increase of the lamp voltage. Further, in the starter 20, the small-capacitance capacitor used in the conventional starter is not necessary, and the resistor 27 is connected in parallel to the pulse-stopping thermal responsive switch used in the conventional starter. Since each function of the bypass resistor and the control resistor connected in parallel to the voltage detection type switching element is combined, the number of parts can be reduced, and the circuit configuration can be simplified and reduced. Cost can be reduced.
[0071]
  In the second embodiment, the case where a semiconductor switching element is used as the voltage detection type switching element has been described. In addition to this, an element that detects a voltage such as a spark gap and performs a switching operation is used. Even in this case, the same effect as described above can be obtained.
[0072]
  In the first and second embodiments, the starter built-in type high-pressure sodium having a rated power of 360 W has been described. However, in addition to the rated power of 360 W, for example, rated power of 110 W, 180 W, 220 W, 270 W, 660 W, and 940 W It can also be applied to high pressure sodium lamps.
[0073]
  In the first and second embodiments, a high-pressure sodium lamp has been described as an example of the high-pressure discharge lamp. However, in the present invention, the envelope in which sodium is sealed has a ceramic arc tube. It can also be applied to metal halide lamps.
[0074]
【The invention's effect】
  As described above, the present invention can suppress the disappearance of sodium sealed in the arc tube, particularly in a high-pressure discharge lamp having a long lamp life, and can be prevented from disappearing due to a change in the emission color of the lamp or an increase in the lamp voltage. It is possible to provide a high-pressure discharge lamp that can be prevented from occurring.
[Brief description of the drawings]
FIG. 1 is a front view of a high-pressure sodium lamp with a built-in starter according to a first embodiment of the present invention.
FIG. 2 is a front sectional view of an arc tube used in a high pressure sodium lamp with a built-in starter.
[Fig. 3] Circuit diagram of a high-pressure sodium lamp with a built-in starter
FIG. 4 is a circuit diagram of a high-pressure sodium lamp with a built-in starter according to a second embodiment of the present invention.
FIG. 5 is a circuit diagram of a conventional high-pressure sodium lamp with a built-in starter.
FIG. 6 is a circuit diagram of another conventional high-pressure sodium lamp with a built-in starter.
[Explanation of symbols]
  1 stem
  2 Outer pipe
  3 base
  4,5 stem wire
  6 arc tube
  7,20 Starter
  8 Starting auxiliary conductor
  9 Envelope
  10 electrodes
  11 Niobium tube
  12 Ceramic cement
  13,14,24 Thermally responsive switch
  15, 26 Heating resistor
  16, 29 High pressure sodium lamp
  17 Copper Iron Reactance Ballast
  18 Lighting circuit
  19 AC power supply voltage
  21 Thermally activated switch for opening the starter
  22 Current limiting resistor
  23 Nonlinear ceramic capacitor elements
  25 Voltage detection type switching element
  27 resistor
  28 Tungsten electrode

Claims (3)

Arc tube having electrodes at both ends;
A starting device connected in parallel to the arc tube;
A starting auxiliary conductor attached to the outer surface of the arc tube ;
With
The starting device includes first and second shut-off thermal responsive switches made of bimetal that is closed at room temperature, and heating resistors provided in close proximity to the first and second shut-off thermal responsive switches at substantially the same distance. Has a series circuit with the body,
One end of the starting auxiliary conductor is connected between the first cutoff thermal responsive switch and the second cutoff thermal responsive switch,
When a current flows through the series circuit, the heating resistor generates heat, and the heat conduction switch opens the first shut-off thermal response switch or the second shut-off thermal response switch, thereby conducting the series circuit. Shut off
Thereafter, after the arc tube is started, the first thermal shutoff switch and the second thermal shutoff switch are configured so that heat from the arc tube is added to residual heat due to heat transfer from the heating resistor. In addition to open each, electrically shut off the starting auxiliary conductor,
A high-pressure discharge lamp characterized by that. Arc tube having electrodes at both ends;
A starting device connected in parallel to the arc tube;
A starting auxiliary conductor attached to the outer surface of the arc tube ;
With
The starting device is provided in the vicinity of the thermal activation switch for interruption for shifting the auxiliary auxiliary conductor to an electrically isolated state after the arc tube is started, and the thermal activation switch for interruption; Having a heating resistor for opening the thermal activation switch for blocking,
A non-linear ceramic capacitor element and a series circuit of the thermal responsive switch for shut-off and voltage detection type switching element having a pulse stop function are connected in series, and the heating resistor is connected to the non-linear ceramic capacitor element and the non-linear ceramic capacitor element. Connected in parallel to the series circuit of the thermal responsive switch for shutoff and the voltage detection type switching element,
High-pressure discharge lamp, wherein said one end of the starting aid conductor is connected between the cut-off thermo-switch voltage sensing switching device, it. The starting device, a high-pressure discharge lamp according to claim 2, wherein said a cut-off thermo-switch said has a voltage sensing type resistor which is connected in parallel with the series circuit of the switching element, it is characterized.

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