JPH022278B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a high-pressure discharge lamp lighting device in which a heater is attached to each of a plurality of high-pressure discharge lamps to improve the rise of luminous flux at startup.

[Prior Art] A high-pressure discharge lamp is equipped with an arc tube filled with a rare gas for starting, mercury, and a metal halide, but such a discharge lamp is started by applying a high-pressure pulse when it is in a low temperature state, for example. Even when lighting is performed, the mercury and metal halides sealed in the arc tube are hardly evaporated, so the rise of the luminous flux is slow, and it takes several minutes for the luminous flux to reach a normal state and stabilize the lighting. There is. For this reason, it may be possible to heat the arc tube by attaching a heater to the arc tube to accelerate the evaporation of the mercury and metal halides sealed therein, thereby improving the rise of the luminous flux during startup.

[Problems to be solved by the invention] However, if this method of heating the high-pressure discharge lamp with a heater is adopted, only one heater is needed when there is only one high-pressure discharge lamp. If you use a heater whose resistance value decreases at low temperatures, it will not be much of a problem even if a certain amount of inrush current flows at the start of energization, but if multiple high-pressure discharge lamps are used, multiple heaters will be used corresponding to the number of discharge lamps. Therefore, if you start energizing each heater at the same time, a considerably excessive in-rush current will flow at the beginning of energization, and a large capacity power supply will be required to cover this, resulting in a large power supply. A problem occurs. In particular, when a battery is used as a power source, a considerably large battery must be prepared, which poses a practical problem.

This invention was made to solve such a problem, and in a device in which a heater is attached to a plurality of high pressure discharge lamps to improve the rise of the luminous flux, each heater is An object of the present invention is to provide a high-pressure discharge lamp lighting device that can prevent an excessive inrush current from flowing into the lamp and use a relatively small-capacity power source.

[Means for Solving the Problems] The present invention provides a plurality of high-pressure discharge lamps, a plurality of lighting circuits connected to a power source and controlling the lighting of each high-pressure discharge lamp, and a plurality of lighting circuits attached to each high-pressure discharge lamp. The heater is provided with a plurality of heaters, and a control means for controlling connection of at least one of the heaters to a power source at a different time timing from that of the other heaters.

[Operation] In the present invention having such a configuration, the start of energization to at least one heater among the plurality of heaters can be performed at a different timing from the start of energization to each of the other heaters. The amount of inrush current at the start can be reduced by one heater.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 1, 1 is a battery as a power source, and a coil 3c of a first relay 3 is connected to this battery 1 via an operation switch 2, and a coil 3c of a first relay 3 is connected via a normally open contact 3m of the first relay 3. Lighting circuits 4, 5, and 6 are connected to each other. High-pressure discharge lamps 7, 8, and 9 are connected to the output terminals of each of the lighting circuits 4, 5, and 6, respectively.

Each of the lighting circuits 4, 5 and 6 is a well-known circuit, and when connected to the battery 1, an internal starting circuit operates to generate a high voltage pulse and apply it to the high pressure discharge lamps 7, 8 and 9. and high pressure discharge lamp 7,
When the discharge lamps 8, 9 start lighting, the operation of the starting circuit is stopped to maintain the lighting of the discharge lamps 7, 8, 9.

Each of the high pressure discharge lamps 7, 8, 9 is provided with a heater 10, 11, 12 for heating, respectively.
A heater 10 attached to the high pressure discharge lamp 7 is connected to the battery 1 via a normally open contact 3m of the first relay 3.

Further, a first time constant circuit 15 is connected to the battery 1 through a normally open contact 3m of the first relay 3, in which a resistor 13 and a capacitor 14 are connected in series. A series circuit of a coil 16c of a second relay 16 and a first NPN transistor 17 is connected in parallel to the first time constant circuit 15. The base of the first transistor 17 is connected to the connection point between the resistor 13 and the capacitor 14 .

A heater 11 attached to the high pressure discharge lamp 8 connects the battery 1 to the normally open contact of the first relay 3.
3m and the normally open contact 16m of the second relay 16 are connected in series.

In addition, the battery 1 has a normally open contact of 3 m of the first relay 3 and a normally open contact of 16 m of the second relay 16.
A second time constant circuit 20 is connected in which a resistor 18 and a capacitor 19 are connected in series. A series circuit of a coil 21c of a third relay 21 and a second NPN transistor 22 is connected in parallel to the second time constant circuit 20.
The base of the second transistor 22 is connected to the connection point between the resistor 18 and the capacitor 19.

A heater 12 attached to the high pressure discharge lamp 9 connects the battery 1 to the normally open contact of the first relay 3.
3m, normally open contact 16m of the second relay 16 and the third
The normally open contacts 21m of the relays 21 are connected in series.

The time constants of the time constant circuits 15 and 20 are set to be equal, for example.

In this embodiment with such a configuration, when the operation switch 2 is turned on, the first relay 3 is operated, and each lighting circuit 4, 5, 6 is operated, and the heater 1 is turned on.
Energization is started only to 0. Also, the first time constant circuit 15 operates. Thus, each of the high-pressure discharge lamps 7, 8, and 9 is started, and the high-pressure discharge lamp 7 is first heated by the heater 10 to promote evaporation of the enclosed metal. A large in-rush current flows through the heater 10 since it is in a low temperature state at the start of energization, but since only the heater 10 is energized, the in-rush current does not become abnormally large.

Then, when time t has elapsed, the first transistor 17 is turned on by the charging voltage of the capacitor 14, and the second relay 16 is activated. Then, energization of the heater 11 is started. At this time, an in-rush current flows through the heater 11, but since the heater 10 has already been heated and the amount of current flowing therethrough is small, the overall amount of current increases but does not become abnormally excessive. Furthermore, the second time constant circuit 20 starts operating due to the operation of the second relay 16. In this way, the high pressure discharge lamp 8 is now heated by the heater 1, and the evaporation of the enclosed metal is promoted.

Then, when time t further passes, capacitor 1
The second transistor 22 is turned on by the charging voltage of 9, and the third relay 21 is operated. Then, energization of the heater 12 is started. At this time, an in-rush current flows through the heater 12, but since the heaters 10 and 11 have already been heated and the amount of current flowing through them has become smaller, the overall amount of current further increases, but each heater 10, 11,
The current does not become abnormally large, unlike when inrush current flows through all 12 at the same time.
In this way, the high pressure discharge lamp 9 is now heated by the heater 12, and the evaporation of the enclosed metal is promoted.

As all the heaters 10, 11, and 12 perform heating operations, the total amount of current flowing through each heater gradually decreases and eventually reaches a certain level.

Therefore, at the time of starting, each high pressure discharge lamp 7,
The total amount of lamp current flowing through lamps 8 and 9 increases immediately after lighting starts, as shown in a in Fig. 2.
The total amount of heater current flowing through each heater 10, 11, 12 increases somewhat as time t elapses, as shown in FIG. 2b, but its peak value does not become very high. Therefore, the peak value of the amount of current supplied by battery 1 can be kept considerably lower than when all heaters start energizing at the same time (indicated by the dotted line in b in Figure 2), and the Even if the capacity of 1 is relatively small, it can be used satisfactorily.

In addition, although the heater is energized at the same time as or after the high-pressure discharge lamp starts lighting, the discharge lamp is heated by the heater at the time of starting, and the rise characteristics of the luminous flux are improved, allowing stable lighting relatively quickly. can be moved to.

Next, another embodiment of the invention will be described with reference to the drawings. It should be noted that the same parts as in the above embodiment are given the same reference numerals and detailed explanations will be omitted.

3, the coil 24c of the fourth relay 24 is connected to the battery 1 through the normally open contact 3m of the first relay 3 and the lamp switch 23 in series, and the coil 24c of the fourth relay 24 is The coil 26c of the fifth relay 26 is connected in series through the normally open contact 3m of the fourth relay 24, the normally open contact 24m of the fourth relay 24, and the lamp switch 25, and the normally open contact of the first relay 3 is connected to the battery 1. The coil 28c of the sixth relay 28 is connected through the contact 3m, the normally open contact 24m of the fourth relay 24, the normally open contact 26m of the fifth relay 26, and the lamp switch 27 in series. Then, a lighting circuit 4 is connected to the battery 1 in a first manner.
Normally open contact 3m of relay 3 and 4th relay 24
The lighting circuit 5 is connected to the battery 1 through the normally open contacts 3m of the first relay 3, the normally open contacts 24m of the fourth relay 24, and the normally open contacts 24m of the fifth relay 26. 26 m of normally open contacts are connected in series, and the lighting circuit 6 is connected to the battery 1 through 3 m of normally open contacts of the first relay 3 and the fourth relay 2.
4 normally open contact 24m, 5th relay 26 normally open contact
26m and the normally open contact 28m of the sixth relay 28 are connected in series.

In this embodiment, even if the operation switch 2 is turned on, the lighting circuits 4, 5, and 6 do not operate, and when the lamp switch 23 is turned on with the operation switch 2 turned on, the lighting circuit 4 is activated and the high-pressure discharge lamp 7 starts to start, and when the lamp switch 25 is turned on, the lighting circuit 5 operates and the high-pressure discharge lamp 8 starts to start. When the lamp switch 27 is turned on, the lighting circuit 6 operates and the high-pressure discharge lamp 9 starts to start. will be done.

Therefore, the operation switch 2 is turned on first, and the heaters 10, 11, 12 are set in advance for each high pressure discharge lamp 7, 8, 9.
When each high pressure discharge lamp 7, 8, 9 is heated sufficiently, each high pressure discharge lamp 7, 8, 9 is heated.
can be started. Therefore, in this embodiment, compared to the previous embodiment, each high pressure discharge lamp 7, 8,
9, the rise of the luminous flux can be better improved.

Of course, in this embodiment as well, each heater 10, 1
Since the start of energization to 1 and 12 is performed sequentially, the same effect as in the previous embodiment can be obtained in that the capacity of battery 1 can be reduced.

In addition, the one shown in Fig. 4 has a first battery in the battery 1.
A third time constant circuit 31 formed by connecting a resistor 29 and a capacitor 30 in series is connected through the normally open contact 3m of the relay 3.
A series circuit of the coil 32c of the seventh relay 32 and the third transistor 33 of NPN type is connected in parallel. and the third transistor 33
The base of the resistor 29 is connected to the connection point between the resistor 29 and the capacitor 30.

Further, the second time constant circuit 20 is connected in parallel to the first time constant circuit 15. Further, a fourth time constant circuit 36 consisting of a resistor 34 and a capacitor 35 connected in series is connected to the first time constant circuit 15, and a resistor 37 and a capacitor 38 are connected to the second time constant circuit 20. A fifth time constant circuit 39 is connected in parallel.

The collector and emitter of a fourth NPN transistor 40 are connected between the base and emitter of the first transistor 17, and the collector and emitter of a fifth NPN transistor 41 are connected between the base and emitter of the second transistor 22. Collector and emitter are connected. The base of the fourth transistor 40 is connected to the connection point between the resistor 34 of the fourth time constant circuit 36 and the capacitor 35, and the base of the fifth transistor 41 is connected to the resistor 37 of the fifth time constant circuit 39.
and the connection point between the capacitor 38 and the capacitor 38.

The heater 10 attached to the high pressure discharge lamp 7 is connected to the battery 1 through the normally open contact 3m of the first relay 3 and the normally closed contact 32b of the seventh relay 32 in series.

Note that the third, fourth, and fifth time constant circuits 31, 3
The time constants 6 and 39 are the first and second time constant circuits 1
The time constant is set considerably larger than the time constants of 5 and 20.

In this embodiment, when the operation switch 2 is turned on, each of the lighting circuits 4, 5, and 6 is activated, and energization of the heater 10 is started. Furthermore, energization of each time constant circuit 15, 20, 31, 36, and 39 is also started. However, each high pressure discharge lamp 7, 8,
9 is started, and the high pressure discharge lamp 7 is first heated by the heater 10. Then, when the time t has elapsed, the charging voltage of the capacitor 17 causes the first
The transistor 17 is turned on, and the second transistor 22 is turned on by the charging voltage of the capacitor 19, and the first and second relays 16,
21 is activated and energization to the heaters 11 and 12 is started. In this way, the high pressure discharge lamps 8 and 9 are also heated. In this case, the first time constant circuit 1
By making the time constant of the second time constant circuit 20 slightly larger than the time constant of the first
Heater energization control similar to the embodiment shown in the figure can be performed.

In this way, each high pressure discharge lamp 7, 8, 9 is connected to the heater 1.
0, 11, and 12, the rise of the luminous flux at the time of starting is improved.

After that, when the discharge lamps 7, 8, and 9 have reached stable lighting, the third transistor 33 is turned on by the charging voltage of the capacitor 30, and the charging voltage of the capacitor 35 turns on the third transistor 33. The fourth transistor 40 is then turned on, and the fifth transistor 41 is turned on by the charging voltage of the capacitor 38.
As a result, the seventh relay 32 operates, its normally closed contact 32b opens, and the power supply to the heater 10 is stopped. Further, the first transistor 17 is turned off, thereby stopping the operation of the first relay 16 and stopping the power supply to the heater 11. moreover,
The second transistor 22 is turned off, thereby stopping the operation of the second relay 21 and stopping the power supply to the heater 12. In this case, each heater 10,
The timing of stopping the energization to 11 and 12 may be different.

In this way, power supply to each of the heaters 10, 11, and 12 is stopped, and wasteful power consumption by the heaters after lighting the discharge lamp is prevented. It also prevents the discharge lamp from being abnormally heated by the heater.

Of course, in this embodiment as well, each heater 10, 1
Since the timing of starting energization to 1 and 12 can be staggered, the same effect as the previous embodiment can be obtained in that the capacity of battery 1 can be reduced.

Note that in this embodiment, each time constant circuit 1
Depending on how the time constants 5, 20, 31, 36, and 39 are set, the energization to the heater 11 may be started after the energization of the heater 10 has stopped, or the energization to the heater 11 may be started after the energization to the heater 11 has been stopped. Starting energization to 12 can also be easily realized.

Moreover, what is shown in FIG.
The off control of heaters 1 and 12 is performed by detecting the temperature of the heater section, and the temperature near each heater 10, 11, 12 is detected by temperature detectors 45, 46, 47 such as junctions or thermistors. That's what I do. and each temperature detector 45,
The outputs of 46 and 47 are respectively input to non-inverting input terminals (+) of comparators 48, 49 and 50 having amplification functions. Each of the comparators 48,
Reference voltages 51, 52, and 49, 50 corresponding to the temperature at which the heater is turned off are connected to the inverting input terminals (-) of 49 and 50, respectively.
53 are input respectively.

On the other hand, the coil 54c of the eighth relay 54 is connected to the battery 1 via the normally open contact 3m of the first relay 3.
and the sixth transistor 55 of the NPN type, a series circuit of the coil 56c of the ninth relay 56 and the seventh transistor 57 of the NPN type is connected, and the coil of the tenth relay 58 is connected. 58c is connected to a series circuit of an eighth transistor 59 of NPN type. The output terminal of the comparator 48 is connected to the base of the sixth transistor 55, and the output terminal of the comparator 49 is connected to the base of the sixth transistor 55.
is connected to the base of the eighth transistor 57, and the output terminal of the comparator 50 is connected to the base of the eighth transistor 57.
It is connected to the base of 9.

The heater 10 attached to the high pressure discharge lamp 7 is connected to the battery 1 through the normally open contact 3m of the first relay 3 and the normally closed contact 54b of the eighth relay 54 in series.

The normally closed contact 56b of the ninth relay 56 is connected to the second
is inserted in series between the coil 16c of the relay 16 and the collector of the first transistor 17.
The normally closed contacts 58b of the ten relays 58 are inserted in series between the coil 21c of the third relay 21 and the collector of the second transistor 22.

In this embodiment, when the operating switch 2 is turned on, each lighting circuit 4, 5, 6 operates, and the high pressure discharge lamps 7, 8, 9 start, and the heater 10
energization starts. The time constant circuit 15, 2
0, the other heaters 11 and 12 are energized with a slight delay. In this way, each voltage discharge lamp 7, 8,
The lamp 9 is heated by the heaters 10, 11, and 12, and is started and turned on with a good rise in luminous flux. As the high-pressure discharge lamps 7, 8, and 9 are turned on, the temperature around the discharge lamps and around the heater gradually rises. When the temperature of the heater section reaches a certain set temperature, for example, the temperature corresponding to when the high pressure discharge lamps 7, 8, 9 shift to stable lighting, the temperature detectors 45, 4
The outputs of the comparators 48 and 47 now exceed the reference voltages 51, 52, and 53.
The outputs of transistors 49 and 50 are inverted from a low level state to a high level state, and the sixth, seventh, and eighth transistors 55, 57, and 59 are turned on.

Therefore, the normally closed contact 54b of the eighth relay 54
is opened and power supply to the heater 10 is stopped, the normally closed contact 56b of the ninth relay 56 is opened and power supply to the heater 11 is stopped, and the normally closed contact 28b of the tenth relay 58 is opened. Then, the power supply to the heater 12 is stopped.

Therefore, this embodiment also provides the same effects as the embodiment shown in FIG. 4 described above.

In this embodiment, the temperature of the heater section is detected, but the temperature of the high pressure discharge lamp section may also be detected.

Furthermore, what is shown in FIG.
Detecting the current flowing through heaters 1 and 12,
0, 11, and 12, and resistors 61, 62, and 6 are connected to each heater 10, 11, and 12, respectively.
3 are inserted in series, and each of the resistors 61, 62, 63
The voltage between terminals of
They are input to the non-inverting input terminals (+) of numbers 9 and 50, respectively. Note that the other circuits are the same as in FIG. 5.

This embodiment utilizes the fact that when the heaters 10, 11, and 12 are initially energized, a large current flows because the resistance value of the heaters is small, but as heating progresses, the heater current gradually decreases.
When the current flowing through 0, 11, 12 decreases to a certain value as heating progresses, each resistor 61, 62, 63
The voltage between the terminals of the output terminals becomes lower than the reference voltages 51, 52, 53, and the outputs of the comparators 48, 49, 50 are inverted to high level. At this time, each high pressure discharge lamp 7, 8,
9 indicates that the reference voltage is 5, which indicates that the lighting is almost stable.
Set 1, 52, 53.

However, the 8th, 9th, and 10th relays 54, 5
6 and 58 are operated, and the energization to each heater 10, 11, and 12 is controlled to be turned off.

Therefore, this embodiment also provides the same effects as the embodiment shown in FIG. 4 described above.

Although each of the embodiments described above does not take into account the charging of the battery 1, for example, as shown in FIG. The power section 72 is then driven by operating the switch 73. In addition, a control switch 74 that is turned on in response to the operation of the switch 73 is connected to each heater 10, 11, 1 from the battery 1.
Inserted in series in the energizing path to 2.

In this embodiment, the power section 72 is driven by operating the switch 73, and the charger 72 is driven.
1 operates and charging of battery 1 is started. At this time, the control switch 74 is turned on to switch the battery 1 to each heater 10, 11, 12.
It becomes possible to energize.

In this way, each heater 10, 11, 12 is energized while the battery 1 is being charged, so even if a large number of heaters are used and their power consumption is large, There is no risk that the voltage of the battery 1 will drop as a result. In other words, each heater 10, 11, 1
There is no possibility that the lighting operation of the high-pressure discharge lamps 7, 8, and 9 will be adversely affected by the energization of the high-pressure discharge lamps 7, 8, and 9.

[Effects of the Invention] As detailed above, according to the present invention, in a plurality of high-pressure discharge lamps each provided with a heating heater for improving the rise of the luminous flux, for each heater. It is possible to provide a high pressure discharge lamp lighting device that can prevent excessive inrush current from flowing and can use a relatively small capacity power source.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram showing one embodiment of this invention, FIG. 2 is a graph showing characteristics of lamp current and heater current in the same embodiment, and FIGS. 3 to 7 are other embodiments of this invention. FIG. 1...Battery, 4,5,6...Lighting circuit,
7, 8, 9...High pressure discharge lamp, 10, 11, 12...
...Heater, 15,20...Time constant circuit, 16,2
1... Relay, 17, 22... NPN type transistor.

Claims (1)

[Scope of Claims] 1. A plurality of high-pressure discharge lamps, a plurality of lighting circuits connected to a power source and controlling lighting of each of the high-pressure discharge lamps, and a plurality of heaters attached to each of the high-pressure discharge lamps, respectively. A high-pressure discharge lamp lighting device comprising: a control means for controlling connection of at least one of the heaters to the power source at a different time timing from that of the other heaters. 2. The high pressure discharge lamp lighting device according to claim 1, wherein the control means disconnects and controls each of the plurality of heaters from the power source at a required timing after energization. 3. Claim 2, characterized in that the control means determines the necessary timing to disconnect the heater from the power source by detecting elapsed time, temperature changes around the high-pressure discharge lamp or the heater, or changes in the current flowing through the heater. The high pressure discharge lamp lighting device described. 4. The high pressure discharge lamp lighting device according to claim 1, wherein the control means sequentially controls the connection of the plurality of heaters to the power source at different time timings. 5. The high pressure discharge lamp lighting device according to claim 4, wherein the control means disconnects the energized heater from the power source and then controls the connection of the next heater to the power source.