JPH03758B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a light compensation device for a high-intensity discharge lamp that compensates for the luminous flux of an illumination lamp consisting of a high-intensity discharge lamp, and particularly relates to a light compensation device for a high-intensity discharge lamp that compensates for the luminous flux of an illumination lamp consisting of a high-intensity discharge lamp. The present invention relates to a light compensation device for a high-intensity discharge lamp when compensation is performed.

(Background of the Invention) High-intensity discharge lamps such as metal halide lamps and mercury lamps have the advantage of higher efficiency than incandescent lamps, but have the disadvantage of slow startup and luminous flux rise after startup. Therefore, in order to perform so-called instantaneous lighting, a halogen lamp with a fast rise in luminous flux is added to the high-intensity discharge lamp lighting device as an auxiliary light source, so that the main illumination, that is, the high-intensity discharge lamp, is lit and the luminous flux exceeds a predetermined level. Optical compensation is performed by turning on the auxiliary light source.

By the way, many such instantaneous lighting devices have been proposed that use one light compensation device for one high-intensity discharge lamp lighting device. If we try to perform optical compensation for multiple lamps, one optical compensation device must be used for each discharge lamp lighting device, which leads to inconveniences such as increased cost and larger size. Ta.

(Object of the Invention) In view of the problems in the conventional type described above, an object of the present invention is to provide a light compensation device for a high-intensity discharge lamp that compensates for the luminous flux of a plurality of main illumination lamps each consisting of a high-intensity discharge lamp. Based on the concept of detecting that all the lights are turned on and controlling the auxiliary light sources provided corresponding to each of the main lighting lights to be turned off all at once, the structure of the device is simplified, and the device is made smaller. The aim is to reduce costs and reduce costs.

(Structure of the Invention) In order to achieve the above object, the present invention provides a light compensation device for a high-intensity discharge lamp that compensates luminous flux at the time of starting and restarting a plurality of main illumination lights each consisting of a high-intensity discharge lamp. an auxiliary light source provided corresponding to each of the main illumination lights, a lighting state detection circuit that detects the lighting state of each of the main lighting lights, and lighting the auxiliary light sources when power is applied to the main lighting lights and detecting the lighting state The present invention is characterized by comprising an auxiliary light source control circuit that turns off the auxiliary light source after detecting that all of the main illumination lights are turned on based on the output of the detection circuit.

(Description of Examples) Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an instantaneous lighting device to which a light compensation device for a high-intensity discharge lamp according to an embodiment of the present invention is applied. In the figure, reference numeral 1 denotes an AC or DC power source, such as an AC power source such as a commercial power source, a DC power source consisting of an AC power source, and a smooth or non-smooth rectifier circuit, or a battery. 2 and 2' are ballasts such as high-frequency lighting circuits (electronic ballasts) and ballasts, and 3 and 3' are high-pressure high-intensity discharge lamps such as metal halide lamps and high-pressure mercury lamps used as main illumination lights. The discharge lamp 3, the ballast 2', and the discharge lamp 3' together with the power source 1 constitute a well-known high-intensity discharge lamp lighting device. Reference numerals 4 and 4' denote auxiliary light sources such as halogen lamps and incandescent lamps whose luminous flux rises quickly, and 5 denotes an optical compensation circuit. It constitutes a light compensation device for electric lights. Auxiliary light sources 4, 4' are provided corresponding to the discharge lamps 3, 3', respectively, and are controlled by a light compensation circuit 5 to compensate for the luminous flux when starting and restarting these discharge lamps 3, 3'. The light compensation circuit 5 connects the discharge lamps 3, 3'
A lighting state detection circuit detects each lighting state, and when the power source 1 is turned on, the auxiliary light sources 4 and 4' are turned on, and based on the output of the lighting state detection circuit, it is detected that all of the discharge lamps 3 and 3' are lit. It also includes an auxiliary light source control circuit that turns off the auxiliary light sources 4 and 4' after detection.

FIG. 2 is a block diagram of an instantaneous illumination device that more specifically shows an embodiment of the optical compensation device for a high-intensity discharge lamp according to the present invention. Note that the same reference numerals are given to the parts common to or corresponding to those of the apparatus shown in FIG. 1, and the description thereof will be omitted.

In FIG. 2, the optical compensation circuit 5 includes lighting state detection circuits 6, 6' and an auxiliary light source control circuit 7.

In the lighting state detection circuit 6, a current transformer 61 generates an induced voltage proportional to the lamp current of the high-intensity discharge lamp 3 flowing through its primary winding, and diodes 62, 6
A rectifying and smoothing circuit including three resistors 64 and a capacitor 65 generates a voltage obtained by rectifying and smoothing the secondary winding induced voltage of the current transformer 61. The inverted discharge trigger circuit 66 compares this voltage with a predetermined threshold value, and outputs a level "H" when the voltage is lower than the threshold value, and outputs a level "L" when the voltage is higher than the threshold value.
Output. Thereby, the lighting state detection circuit 6 detects the lighting state of the discharge lamp 3, that is, the luminous flux level, based on the voltage, that is, the lamp current (average value) of the discharge lamp 3, and when the luminous flux level exceeds a predetermined value, it becomes "L". When the luminous flux level is below a predetermined value, a light-off detection signal of "H" level is generated. Diodes 67 and 68 are for protecting the Schmitt trigger circuit 66 from noise such as surge voltage. The lighting state detection circuit 6' does not detect the lamp current of the discharge lamp 3'.
Since it is configured in exactly the same way as the lighting state detection circuit 6, the explanation will be omitted by indicating the common parts with the same numbers with a dash.

In the auxiliary light source control circuit 7, a logic circuit 71
operates as a negative logic NAND circuit for the "L" level lighting detection circuit, and as a positive logic NOR circuit for the "H" level lighting detection signal. Therefore, when both the discharge lamps 3 and 3' are lit and the lighting state detection circuits 6 and 6' both generate "L" level lighting state detection signals,
It generates an AND output of "H" level, and when one of the discharge lamps 3 and 3' goes out and the lighting state detection circuit 6 or 6' generates a light-off detection detection signal of "H" level, it goes to "L" level. Generates a logical sum output. A differentiating circuit consisting of a capacitor 72 and a resistor 73 differentiates the rising edge of the "H" level AND output, and an inverted output trigger circuit 74 shapes this differential waveform to generate a "L" level pulse. do. This pulse is supplied to the timer circuit 75 as a timer start signal, and the timer circuit 75 sets its output, sets a clock value, and starts counting time. Inverter 76 is circuit 71
The logical sum output of is inverted to "H" level, and the differentiating circuit and inverted output trigger circuit 79 consisting of a capacitor 77 and resistor 78 differentiates the rising edge of this logical sum output which has been inverted to "H" level. It is shaped and inverted to generate an "L" level pulse. This pulse is supplied to the timer circuit 75 as a reset signal, and when the output of the timer circuit 75 is at the "H" level, it is forcibly reset to this level. Note that the timer circuit 75 turns on the auxiliary light sources 4 and 4' for a certain period of time sufficient for the luminous flux to rise even after the lighting of the discharge lamp 3 is detected, thereby preventing a lack of luminous flux after starting until the luminous flux rises. This increases the tolerance of the lamp current detection level and makes lighting detection easier.

Next, the operation of the instantaneous lighting device shown in FIG. 2 will be explained with reference to the voltage and current waveforms of each part shown in FIG.

First, when the power switch 9 is turned on at time t0, the lighting circuits 2, 2' start preheating the discharge lamps 3, 3'. At this time, since the lamp currents of the discharge lamps 3 and 3' are zero (Figures A and B), the lighting state detection circuit 6,
6', the secondary winding induced voltage of the current transformers 61, 61' is sufficiently lower than the threshold value of the Schmitt trigger circuits 66, 66', and the output of the circuits 66, 66', that is, the lighting state detection circuits 6, 6'. Both outputs are at "H" level (Figures C and D). Therefore, in the auxiliary light source control circuit 7, the output of the logic circuit 71 is "L" (Fig. E), and the output of the inverter 76 is "H".
The output of the OR circuit 80 becomes "H", the transistor 81 is turned on, the relay 82 is driven, the contact 8 is closed, and the auxiliary light sources 4 and 4' are turned on by the power source 1 (Figure H).

Next, the discharge lamp 3 is preheated for, for example, 2 to 3 minutes and then starts (Figure A, time t1), and the lamp current of the discharge lamp 3 exceeds a predetermined value I _L (Figure A, time t2), and the current change occurs. When the rectified and smoothed voltage induced in the secondary winding of the regulator 61 exceeds the threshold of the Schmitt trigger circuit 66,
The lighting state detection circuit 6 generates a lighting detection signal of "L" level (Figure C, time t2). However, the discharge lamp 3' has not started yet (Figure B), and the output of the lighting state detection circuit 6' remains at the "H" level (D
figure). Therefore, the output of the logic circuit 71 is "L" level, the output of the inverter 76 is "H", the output of the OR circuit 80 is "H", the transistor 81 and the relay 82 are turned on, and the contact 8 is turned on, as described above. The circuit is closed, and the auxiliary light sources 4 and 4' remain lit (H
figure).

Subsequently, discharge lamp 3' starts (Figure B, time t1')
When the lamp current exceeds a predetermined value I _L (Figure B, time
t2'), the lighting state detection circuit 6' detects the lighting of the discharge lamp 3' and generates an "L" level lighting detection signal (time t2' in Figure D). Therefore, the two inputs of the logic circuit 71 are both at "L" level (C, D
), generates an “H” level AND output (E
figure). The rising edge of this AND output is differentiated by a differentiating circuit consisting of a capacitor 72 and a resistor 73, and then waveform-shaped and inverted by a Schmitt trigger circuit 74 (FIG. F), and is supplied to a timer circuit 75 as a start signal. As a result, the timer circuit 75 clears the clock value and generates an "H" level output (Figure G) and starts clocking. In this case, the output of the inverter 76 becomes "L" level, but since the "H" level output (Figure G) of the timer circuit 75 is applied to one input terminal of the OR circuit 80, the output of the OR circuit 80 is is “H” level,
The contact 8 of the relay 82 is closed, and the auxiliary light sources 4 and 4' remain lit (Figure H).

Subsequently, when the timer circuit 75 finishes counting the predetermined time and the output becomes "L" level (Figure G, t3),
In the OR circuit, both inputs are at “L” level,
The output becomes "L", the relay 82 is deenergized, the relay contact 8 is opened, and the auxiliary light sources 4, 4' are extinguished (Figure H).

Next, the operation after the discharge lamp 3 goes out (Fig. A, t4) will be explained.

In this case, the lamp current of the discharge lamp 3 becomes zero (Fig. A, t4 to t5), and the output of the lighting state detection circuit 6 becomes "H" level. Therefore, the OR inverted output of the logic circuit 71 becomes "L" level, and the above-mentioned (t0
~t2'), the relay 82 is energized, and the contact 8
is closed and the auxiliary light sources 4, 4' are turned on (Figure H).
When a discharge lamp goes out, it does not restart immediately because while the lamp temperature is high, the gas pressure inside the lamp is high and the restriking voltage is high. For this reason,
The discharge lamp 3 gradually cools down and restarts only when the restriking voltage becomes lower due to the non-negative output voltage of the lighting device 2 (Fig. A, t5). In this case (after t5), the process and operation are similar to those at the time of starting (after t1), so the explanation will be omitted.

Next, when the discharge lamp 3' goes out while the output of the timer circuit 75 is at "H" level (Figure B, t7)
Explain the operation. In this case, the lighting state detection circuit 6 generates an "H" level extinction detection signal, and after the output of the timer circuit 75 is forcibly reset, the above-mentioned discharge lamp 3 goes out (Figure A, t4). works the same way.

This instantaneous lighting device turns off the auxiliary light source after detecting that all of the plurality of lighting lights are turned on, and also turns off all the auxiliary light sources when at least one of the lighting lights goes out or goes out. Since it can be turned on, it is suitable for use in automobile headlights, for example, because even if one of the main illumination lights goes out due to a failure, the auxiliary light source will turn on and the headlight will not be turned on in one direction, making it safer.

It should be noted that the present invention is not limited to the above-described embodiments, and can be implemented with appropriate modifications within the scope of the spirit of the present invention. For example, in the embodiments described above, each main illumination light is composed of one discharge lamp, but any or all of the main illumination lights may be composed of two or more discharge lamps. Also,
In the above, each main lighting lamp is driven by one lighting circuit, but for example, two discharge lamps of a two-lamp type discharge lamp lighting device are used, one each as two main lighting lights. For example, one ballast may be used for multiple main lighting lights. moreover,
In the above description, the lighting state of each main illumination lamp is detected based on the lamp current value, but the discharge lamps 3 and 3'
Other known methods of detecting the lamp voltage, power or illuminance or luminous flux of the lamp may also be used.

(Effects of the Invention) As described above, according to the present invention, since the auxiliary light sources provided corresponding to each of the plurality of illumination lights are collectively controlled by one optical compensation device,
The configuration of the device is simplified, and the device can be made smaller and lower in cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an instantaneous lighting device to which a high-intensity discharge lamp light compensation device according to an embodiment of the present invention is applied, and FIG. 2 is a block diagram of a high-intensity discharge lamp light compensation device according to an embodiment of the present invention. A block diagram of the instantaneous illumination device showing the optical compensation circuit part of the device in more detail, and a third
The figure is a waveform diagram of each part of the optical compensation circuit of FIG. 2. 1...power supply, 2,2'...ballast, 3,3'...
High-intensity discharge lamp (main illumination lamp), 4, 4'... Auxiliary light source, 5... Light compensation circuit, 6, 6'... Lighting state detection circuit, 7... Auxiliary light source control circuit, 8... Relay contact , 61, 61'...Current transformer, 71...NOR circuit (negative logic NAND circuit).

Claims (1)

[Scope of Claims] 1. A light compensation device for a high-intensity discharge lamp that compensates the luminous flux during starting and restarting of a plurality of main illumination lamps consisting of high-intensity discharge lamps, which is provided corresponding to each of the main illumination lamps. an auxiliary light source, a lighting state detection circuit that detects the lighting state of each of the main lighting lights; A light compensation device for a high-intensity discharge lamp, comprising: an auxiliary light source control circuit that turns off the auxiliary light source after detecting that all of the main illumination lights are turned on. 2. The lighting state detection circuit generates a lighting detection signal when the luminous flux of each of the main lighting lamps exceeds a predetermined level, and the auxiliary light source control circuit generates a lighting detection signal by calculating the AND of the lighting detection signals. A light compensation device for a high-intensity discharge lamp according to claim 1, which detects whether any of the illumination lights are turned on. 3. The lighting state detection circuit generates a light-off detection signal when the luminous flux of each of the main lighting lamps falls below a predetermined level, and the auxiliary light source control circuit generates a light-off detection signal by calculating the logical sum of the light-off detection signals. The light compensation device for a high-intensity discharge lamp according to claim 1 or 2, wherein the auxiliary light source is turned on when it is detected that at least one of the illuminating lights is turned off. 4. The light compensation device for a high-intensity discharge lamp according to claim 1, 2 or 3, wherein the lighting state detection circuit detects the lighting state based on the lamp current of the main illumination lamp.