JPH04233198A - Discharge lamp lightening device - Google Patents

Abstract

PURPOSE:To secure safety and enable the relighting of a lamp without resetting the power source and further prevent the relighting a discharge lamp in the case that it goes out after having shown abnormal lightening. CONSTITUTION:A pulse stop circuit 10 is driven by the voltage based on the lamp voltage of the secondary winding L1 of a stabilizer, that is, an HID lamp 2. The pulse stop circuit 10 counts it with the lamp voltage at the time of abnormal lighting of the HID lamp 2, and enables the relighting of the HID lamp 2 without resetting the power source. Moreover, a high voltage pulse generating circuit 7 generates high voltage pulses by supplied with the lamp voltage at lights-out, and at the time of abnormal lighting of the HID lamp 2, a timer 9 counts up it without generating high voltage pulses. Accordingly, it never relights after lights-out of an inferior HID lamp 2.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a discharge lamp lighting device.
In particular, the present invention relates to a discharge lamp lighting device suitable for lighting small metal halide lamps and the like.

0002

[Prior art] Conventionally, HID such as metal halide lamps
(High Intensity Discharge
) Lamps are used for outdoor lighting because they are highly efficient and have high brightness. In an HID lamp, after the start of discharge, the temperature of the arc tube rises and the vapor pressure of the enclosed substance rises, and it takes several minutes for the lamp to reach a normal lighting state.

In a conventional discharge lamp lighting device for lighting such an HID lamp, a low frequency commercial AC power source of 100 V or 200 V and 50 Hz or 60 Hz is used as the power source. A power supply voltage from a commercial AC power supply is applied to a ballast, and a secondary voltage appearing at a secondary winding of the ballast is supplied to the HID lamp via a starter.

The starter has a high voltage pulse generating circuit. The high-voltage pulse generation circuit is supplied with the secondary voltage of the ballast, and for example, uses a high-voltage pulse (several thousand volts) to start an HID lamp using an SSS (two-terminal thyristor).
occurs. The high voltage pulse generation circuit stops generating high voltage pulses when the HID lamp lights up.

By the way, in order for the HID lamp to light up, the temperature of the arc tube must be low. Therefore, the time it takes to turn on the lamp differs depending on the temperature of the arc tube when the power is turned on. For example, after the lamp is turned off, it takes several minutes for the temperature of the arc tube to drop to a state where it can be lit again. For this reason, the high voltage pulse generation circuit is capable of continuously generating high voltage pulses when the power is turned on.

However, at the end of the lamp life,
If there is an abnormality in the HID lamp, the lamp voltage may rise after the lamp is turned on and the lamp may turn off. In this case, there is a risk that a high voltage pulse will occur again and the HID lamp will turn on and blink repeatedly. Moreover, even if the HID lamp is abnormal and does not light up, high voltage pulses are continuously generated. Since the high-voltage pulse voltage is extremely high, in this case it is dangerous because it adversely affects wiring and equipment.

[0007] Therefore, a pulse stop circuit that controls the generation time of the high voltage pulse is sometimes employed. The pulse stop circuit has a timer and calculates the elapsed time after the power is turned on. Normally, in order to ensure reliable lighting, the pulse stop circuit operates the high-voltage pulse generation circuit for several minutes (for example, 20 minutes) after power is turned on, and then stops the generation of high-voltage pulses. In this way, safety is ensured by the pulse stop circuit.

However, the HID lamp may go out after the high voltage pulse is stopped by the pulse stop circuit due to, for example, a momentary power outage or power supply voltage fluctuation. Even in this case, no high voltage pulse is generated, so the power supply must be reset in order to light up the HID lamp again. For example, in a store, etc., when one HID lamp goes out, in order to turn that HID lamp back on, it is necessary to turn off the power, turn off all other HID lamps, and then wait several minutes to turn it back on. time is required.

[0009]

[Problems to be Solved by the Invention] As described above, in the above-mentioned conventional discharge lamp lighting device, if a pulse stop circuit is not adopted, an abnormal discharge lamp may repeatedly blink. However, when a pulse stop circuit is adopted, there is a problem in that the power supply must be reset in order to light the lamp again after the generation of high-voltage pulses has stopped.

The present invention has been made in view of the above problems, and it ensures safety, makes it possible to re-light the lamp after it has been turned off without resetting the power supply, and also enables the discharge lamp to be turned on abnormally. An object of the present invention is to provide a discharge lamp lighting device that can prevent relighting when a discharge lamp goes out.

[0011]

[Means for Solving the Problems] A discharge lamp lighting device according to claim 1 of the present invention is provided with a secondary voltage of a ballast and generates a high voltage pulse for lighting the discharge lamp at the time of starting the discharge lamp. and a pulse stop circuit that is supplied with the secondary voltage of the ballast as an operating voltage and controls generation and stop of high-voltage pulses from the high-voltage pulse generation circuit according to the state of the discharge lamp. The discharge lamp lighting device according to claim 2 of the present invention is provided with a high voltage pulse that is supplied with the secondary voltage of the ballast and generates a high voltage pulse for lighting the discharge lamp at the time of starting the discharge lamp. The secondary voltage of the generating circuit and the ballast is supplied as an operating voltage, and when the secondary voltage during normal lighting of the discharge lamp is supplied, the secondary voltage is reset when the discharge lamp is abnormally lit and turned off. The apparatus is equipped with a pulse stop circuit that starts counting when a voltage is supplied, counts up after a predetermined period of time, and stops generating high voltage pulses from the high voltage pulse generating circuit during periods other than the counting period.

0012

[Operation] According to claim 1 of the present invention, the pulse stop circuit receives the secondary voltage of the ballast, that is, the lamp voltage of the discharge lamp as an operating voltage, and controls the high-voltage pulse generation circuit according to the state of the discharge lamp. do. This ensures safety and enables good lighting and relighting.

In the second aspect of the present invention, the high voltage pulse generating circuit is supplied with the secondary voltage of the ballast and generates a high voltage pulse for lighting the discharge lamp when the discharge lamp is started. When the power is turned on, a secondary voltage higher than the secondary voltage during normal lighting of the discharge lamp is supplied to the pulse stop circuit, the pulse stop circuit starts counting, and the high voltage pulse generating circuit generates high voltage pulses. When the discharge lamp lights up normally,
The pulse stop circuit is reset. From now on, even if the discharge lamp goes out, the count will start again without resetting the power supply, and the high-voltage pulse generation circuit will operate.
It becomes possible to relight the discharge lamp. Further, the pulse stop circuit performs a counting operation even when the discharge lamp is abnormally lit, and counts up after a predetermined time. Therefore, even if the discharge lamp is turned off after abnormal lighting, the high voltage pulse generation circuit does not generate a high voltage pulse and the discharge lamp does not turn on again.

[0014]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram showing an embodiment of a discharge lamp lighting device according to the present invention.

One end of a secondary winding L1 of a ballast (not shown) is connected to a terminal a of the fuse 1, and the other end is connected to a reference potential point. Terminal b of fuse 1 is pulse transformer PT
The secondary winding L3 of the transformer PT and the HID lamp 2 (not shown) are connected between this midpoint and the reference potential point. Between the midpoint of the transformer PT and the reference potential point, capacitors C1 and C2 and transformer P
T's primary winding L4, coil L5, resistors R1 to R
7, a high-voltage pulse generation circuit 7 constituted by SSSs 3 and 4, a triac 5, and a diac 6b as a photo-receiving element of a photocoupler is also connected.

That is, the midpoint of the transformer PT is connected to a reference potential point via capacitors C1, C2 and triac 5, and a resistor R1 is connected in parallel to capacitor C1. In addition, a series circuit of a primary winding L4, a coil L5, and SSS3, 4 is connected in parallel with the capacitor C1, and resistors R2 to R5 are connected in parallel with the capacitor C2.
series circuit is connected. A series circuit including a resistor R6, a diac 6b, and a resistor R7 is connected in parallel to the triac 5. The diac 6b is turned on and provides an on-pulse to the triac 5 when a light emitting diode 6a of a photocoupler, which will be described later, is turned on and emits light. The triac 5 is turned on by an on pulse from the diac 6b. Note that, when the lamp voltage VL of the HID lamp 2 becomes 150V or more due to the SSSs 3 and 4, the high voltage pulse generation circuit 7
It is capable of generating high voltage pulses.

On the other hand, 2 appearing in the secondary winding L1 of the ballast
The next voltage is taken out by winding L2 and pulse stop circuit 1
0. Winding L2 is resistor R
A Zener diode ZD1 and a smoothing capacitor C3 are connected in parallel between the positive output terminal and the negative output terminal of the full-wave bridge rectification circuit 8. The timer 9 is operated by voltages from the full-wave bridge rectifier circuit 8, the Zener diode ZD1, and the smoothing capacitor C3.

That is, pins 3 and 7 of the timer 9 are connected to the positive output terminal of the full-wave bridge rectifier circuit 8;
The number pin is connected to the negative output terminal. The No. 1 pin of the timer 9 is connected to the positive output terminal via the diode D1 and to the negative output terminal via the capacitor C4. Furthermore, pin 1 of timer 9 is connected to resistor R9.
and a negative polarity output terminal via a capacitor C5, and the fifth pin is connected to a connection point between a resistor R9 and a capacitor C5. These capacitors C4, C5 and resistor R9 constitute a time constant circuit, and the timer 9
The oscillation frequency of a built-in oscillator (not shown) is determined.

The timer 9 operates when a predetermined voltage appears between the positive output terminal and the negative output terminal of the full-wave bridge rectifier circuit 8. This predetermined voltage is adjusted by a resistor R8, and in this embodiment, when the secondary voltage of the ballast (lamp voltage VL) becomes 105V or more, a counting operation is started, and when the lamp voltage VL becomes 105V or less, it is reset. It is now possible to do so. The timer 9 counts the oscillation pulses of the built-in oscillator, and from the start of counting until the count value reaches a predetermined value (for example, equivalent to 20 minutes), a high level (hereinafter referred to as
Outputs an output (referred to as “H”). Timer 9 number 2,
The 6th pin is commonly connected, and when the count value reaches a predetermined value, the 2nd pin is set to low level (
(hereinafter referred to as "L"). The timer 9 can restart counting only if it is reset after counting up.

[0020] The 2nd and 6th pins of the timer 9 are resistors R10.
is connected to the base of transistor Q via. The base of the transistor Q is connected to the negative polarity output terminal of the full-wave bridge rectifier circuit 8 through a parallel circuit of a capacitor C6 and a resistor R11, and the collector is connected to the positive polarity through a photocoupler light emitting diode 6a, a Zener diode ZD2, and a resistor R12. The emitter is connected to the negative output terminal, and the emitter is connected to the negative output terminal.

Next, the operation of the discharge lamp lighting device constructed as described above will be explained with reference to FIG. In Figure 2, the horizontal axis represents the power supply voltage, the vertical axis represents the lamp voltage VL, and H
It is a graph showing the normal lighting area (shaded area) of the ID lamp 2.

When the HID lamp 2 is started, a secondary voltage of about 230 V is applied from the ballast, and a high voltage pulse of several thousand volts is supplied from the high voltage pulse generating circuit 7, so that the HID lamp 2 lights up. When the HID lamp 2 is normally lit, the lamp voltage VL is within the range of 80 to 105V, as is clear from the normal lighting region indicated by the hatched area in FIG. Also, at the end of the life of the HID lamp 2,
It is assumed that the HID lamp 2 does not light up normally and the lamp voltage VL remains in the range of 105 to 150V for a relatively long time.

[0023] At the start of lamp lighting, 100
By turning on the AC power supply of V, a secondary voltage of approximately 230 V appears at the secondary winding L1 of the ballast. The voltage induced in the winding L2 is generated by a resistor R8, a full-wave bridge rectifier circuit 8,
Zener diode ZD1 and smoothing capacitor C3
A predetermined constant voltage is obtained. Due to this constant voltage, the timer 9 starts counting operation, and the second pin exhibits "H". Then, the transistor Q is turned on, a voltage based on the resistor R12 and the Zener diode ZD2 is applied to the light emitting diode 6a of the photocoupler, and the light emitting diode 6a is turned on. Then, the diac 6b as a light-receiving element is turned on, an on-pulse is supplied to the triac 5, and the triac 5 is turned on.

Thereby, the secondary voltage is applied to the midpoint of the pulse transformer PT via the fuse 1, and the secondary voltage is applied to the midpoint of the pulse transformer PT through the fuse 1.
1 and C2 are charged. When the capacitor C1 is charged and its terminal voltage reaches the break voltage of SSS3,4, the charge of the capacitor C1 is transferred to the transformer PT.
Discharge occurs through the primary winding L4, coil L5, and SSS3, 4, and a pulse is generated in the primary winding L4. Note that the capacitor C2 is for voltage division, and is used to match the phases. Also, coil L4
is for peak adjustment of pulses generated in the primary winding L4.

The pulse generated in the primary winding L4 is boosted by the pulse transformer PT, and a high voltage pulse of several thousand volts is generated in the secondary winding L3. As a result, the HID lamp 2 is turned on, and the lamp voltage VL decreases to the voltage range of 80 to 105 V shown by diagonal lines in FIG.

During normal lighting, the lamp voltage is maintained within the range of 80 to 105V. Lamp voltage VL is 105
By lowering than V, the full-wave bridge rectifier circuit 8
The voltage at the positive output terminal of the diode D1 is turned on, and the timer 9 is reset. In addition, H.I.D.
When the lamp 2 is turned on and the lamp voltage VL becomes 150V or less, the high voltage pulse generation circuit 7 stops generating high voltage pulses.

Now, assume that the HID lamp 2 goes out due to a momentary power outage or the like. Then, the lamp voltage VL
becomes higher than 150V, the timer 9 starts counting again, and the high voltage pulse generation circuit 7 generates a high voltage pulse again. The timer 9 outputs an "H" output from the second pin for 20 minutes from the start of counting, and the HID lamp 9 is reliably lit again.

Here, it is assumed that the HID lamp 2 is at the end of its life. In this case, the lamp voltage VL of the HID lamp 2 may become higher than 105V after lighting, and the HID lamp 2 may almost go out. Lamp voltage VL is 10
By becoming higher than 5V, the timer 9 starts counting again. As a result, the light emitting diode 6a and the diac 6b are turned on, the triac 5 is turned on, and the capacitors C1 and C2 are charged. However, in this case, the HID lamp 2 is not definitely turned off, so the lamp voltage VL does not easily reach 150V. When 20 minutes have passed, the second pin of the timer 9 becomes "L", and the light emitting diode 6a and diac 6b are turned off. That is, when 20 minutes have passed since the abnormal lighting of the HID lamp 2, the triac 5 is turned off, and even if the lamp voltage VL increases thereafter, the high voltage pulse generation circuit 7 does not generate high voltage pulses. Therefore, H at the end of life
Even if the ID lamp 2 goes out, it will not be turned on again, and the lamp will not blink repeatedly.

As described above, in this embodiment, the count of the timer 9 of the pulse stop circuit 10 is controlled by the secondary voltage of the ballast, that is, the lamp voltage VL. The timer 9 is reset when the HID lamp 2 lights up normally, so even if it goes off when the power is turned on for some reason, the timer 9 restarts counting, and the high voltage pulse generation circuit 7 generates a high voltage pulse to turn on the HID lamp 2. will be lit again. Therefore, when supplying power supply voltage to multiple HID lamps from one power supply, one HI
Even if the D lamp goes out, turn off the power supply voltage and turn off all H lamps.
A lamp that has been turned off can be turned on again without turning off the ID lamp. In addition, the pulse stop circuit 10 operates the high voltage pulse generation circuit 7 when the HID lamp 2 turns on abnormally when it is reset, and the high voltage pulse generation circuit 7 activates the high voltage pulse generation circuit 7 when the HID lamp 2 is definitely turned off. is set to generate only high-voltage pulses. Therefore, if the HID lamp 2 turns on abnormally, such as at the end of its lifespan, the timer 9 will count up before a high-voltage pulse is generated, so even if the HID lamp 2 is turned off, it will not be turned on again. There will be no repeated flashing.

Incidentally, the device shown in FIG. 3 is sometimes employed as a lighting device for a discharge lamp such as an HID lamp having a pulse stop circuit and a high-voltage pulse generation circuit.

AC power supply voltage from a commercial AC power supply 21 is applied to the primary winding 22 of the ballast. At the start of lighting, a secondary voltage of approximately 230V is generated in the secondary winding 23 of the ballast. The pulse stop circuit 24 operates by being supplied with an operating voltage from the center tap of the primary winding 22 of the ballast, and stops the operation of the high voltage pulse generation circuit 25 when a predetermined period of time has elapsed since the power was turned on. . High voltage pulse generation circuit 2
5 generates a pulse for lighting the HID lamp 27. This pulse is boosted by a pulse transformer 26 and supplied to an HID lamp 27.

Conventionally, it has been common for pulse stop circuits to obtain an operating voltage by lowering the AC power supply voltage of a commercial AC power supply to a predetermined voltage using a resistor or the like. However, in this case, the resistance consumes power and generates heat. In contrast, in FIG. 3, the pulse stop circuit 24 obtains its operating voltage from the center tap of the primary winding 22, which has the advantage of reducing power consumption and heat generation.

In addition, in FIG. 4, the voltage appearing at the primary winding 22 of the ballast is stepped down by the transformer 28,
The operating voltage of the pulse stop circuit 24 is obtained. Also in FIG. 4, the same effect as in FIG. 3 can be obtained.

[0034]

[Effects of the Invention] As explained above, according to the present invention, safety can be ensured, the lamp can be relit without resetting the power supply, and furthermore, the abnormally lit discharge lamp can be turned off. This has the effect of preventing re-lighting in the case of

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of a discharge lamp lighting device according to the present invention.

FIG. 2 is a graph for explaining the operation of the embodiment.

FIG. 3 is a circuit diagram showing another discharge lamp lighting device.

FIG. 4 is a circuit diagram showing another discharge lamp lighting device.

[Explanation of symbols]

2...HID lamp 7...High voltage pulse generation circuit 9...Timer 10...Pulse stop circuit

Claims (2)

[Claims] 1. A high-voltage pulse generation circuit that is supplied with a secondary voltage of a ballast and generates a high-voltage pulse for lighting the discharge lamp at the time of starting the discharge lamp; A discharge lamp lighting device comprising: a pulse stop circuit that is supplied and controls generation and stop of high-voltage pulses from the high-voltage pulse generating circuit according to a state of the discharge lamp. 2. A high-voltage pulse generation circuit that is supplied with a secondary voltage of a ballast and generates a high-voltage pulse for lighting the discharge lamp at the time of starting the discharge lamp; When the secondary voltage is supplied and the discharge lamp is normally lit, it is reset, and when the secondary voltage is supplied when the discharge lamp is abnormally lit and turned off, it starts counting, and after a predetermined period of time, it starts counting. 1. A discharge lamp lighting device comprising: a pulse stop circuit that stops the generation of high voltage pulses from the high voltage pulse generation circuit during a period other than the counting period.