JP2007066629A - Discharge lamp lighting device and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device and a lighting system in which difference of temperature rise of a filament due to difference of accumulative lighting time period of the discharge lamp or due to difference of discharge lamps are reduced and proper preheating can be achieved. <P>SOLUTION: Operation of the lighting device 3 is regulated so that a operation controller 14 may output a filament current I1 during a period T1 when the discharge lamp 4 is turned on. A filament resistivity detector 10 detects filament resistivity after the period T1. Then the operation controller 14 sets the length of period t2 and/or filament current i2 in accordance with the detected value of this filament resistivity and controls operation of the lighting device so that the output may be at the set value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device for lighting a hot cathode discharge lamp, and an illumination device using the discharge lamp lighting device.

  Whether a hot-cathode discharge lamp is properly preheated during start-up affects startability and lamp life. For this reason, a so-called soft start for supplying a preheating current to the filament before applying a starting voltage to both ends of the lamp has been put into practical use.

  However, in the past, the filament was preheated before applying a high voltage for starting as in the soft start method, but the degree of preheating was fixed by the lighting device. In other words, the appropriate preheating conditions for the filament (conditions for the filament temperature to reach an appropriate temperature for electron emission) are the extent of decrease in the emitter due to the cumulative lighting time of the discharge lamp, which also differs depending on the individual discharge lamp. Does not correspond to such a situation.

On the other hand, Patent Document 1 focuses on the resistance value of the filament, and when the ratio (Rh / Rc) between the cold resistance value (Rc) and the resistance value (Rh) after preheating reaches a predetermined value, the proper preheating state is achieved. The technology to be there is shown.
Japanese Patent Laying-Open No. 2004-221027 (paragraph “0021”)

  In Patent Document 1, the time required for the ratio (Rh / Rc) of the cold resistance value (Rc) to the preheated resistance value (Rh) to reach a predetermined value set in advance is the allowable minimum set in advance. If the preheating time has been reached, the starting voltage is applied as a normal lamp, but if the allowable minimum preheating time has not been reached, it is determined that the lamp has reached the end of its life.

  Thus, the thing of patent document 1 only shows the judgment method of the appropriate preheating state of a filament, and does not mention the means to implement | achieve the appropriate preheating corresponding to the actual condition of each discharge lamp.

  However, as described above, the actual discharge lamp has a different degree of filament emitter reduction depending on the cumulative lighting time, and the filament temperature varies even when the same filament current is supplied according to the emitter reduction degree. It can be inferred that this is due to the difference in the heat capacity of the filament depending on the degree of decrease in the emitter.

  Therefore, the conventional one in which the preheating condition is fixed cannot cope with the actual situation of each discharge lamp, and for example, the filament whose emitter is decreased to some extent may be excessively heated and the filament may be disconnected. There is.

  Disclosed is a discharge lamp lighting device and an illuminating device that can realize appropriate preheating by reducing a difference in filament temperature rise due to a difference in accumulated lighting time of a discharge lamp or a difference in filament temperature rise due to variations in individual discharge lamps. The purpose is to provide.

  A discharge lamp lighting device according to a first aspect of the present invention is a variable output lighting device that supplies filament preheating power to the hot cathode discharge lamp and supplies lighting power; and resistance detection means for detecting a resistance value of the filament; The operation is controlled so as to control the output of the lighting device, which includes a period T1 for supplying a filament current I1 as a filament preheating period, a period t2 for supplying a filament current i2 following the period T1, and a period T1 And a lighting device operation control means for controlling at least one of the filament current i2 and the supply period t2 in the period t2 in accordance with the filament resistance detection value of the subsequent resistance detection means.

  In the present invention and the following inventions, definitions and technical meanings of terms are as follows.

  The hot cathode type discharge lamp has a preheated filament electrode, and may be used for general lighting, sterilization, decoration, etc. Any shape such as a so-called compact shape may be used.

  The lighting device preferably includes a high-frequency generator from the viewpoint of ease of output control, but may be a DC lighting type or a commercial frequency lighting type. One way to change the output of these lighting devices is to control the input or output voltage of the lighting devices. This can be realized, for example, by providing pulse width control means and phase control means on the input side or output side. Moreover, you may make it provide the impedance apparatus for shunting or partial pressure so that insertion or removal is possible.

  When the lighting device is composed of high frequency generation means such as an inverter, the output may be changed by controlling the oscillation frequency of the high frequency generation means. That is, by controlling the oscillation frequency, the output of the resonance circuit normally included in the high-frequency generating means is changed, or the output is changed by using the change of the impedance value of the inductive or capacitive impedance device. Can do.

  Further, since the lighting device includes a high pressure generating means for starting the discharge lamp, the discharge lamp can be started more reliably, and the lighting voltage can be relatively reduced to reduce the size of the current limiting impedance device. It is preferable in that it can be achieved.

  The resistance detection unit can be obtained by calculation using detection values of the current detection unit and the voltage detection unit, for example. In this case, the detection values of the current detection means and the voltage detection means can be converted from analog to digital, and can be arithmetically processed by, for example, an operation control device described later.

  It is advantageous in terms of downsizing and processing speed that the operation control device is constituted by an IC, a microcomputer or the like. In the operation control device, “control at least one of the filament current i2 and the supply period t2 in the period t2 according to the filament resistance detection value of the resistance detection means” may be used as it is. In this case, the filament preheating in the period t2 is controlled according to the detected (or calculated) filament resistance value itself, and the influence due to the difference in electrical characteristics between the filaments appears relatively large in the preheating condition.

  On the other hand, in the present invention, the cold resistance value of the self filament is measured and stored, and the ratio (filament resistance detection value / cold resistance value) with the filament resistance detection value is obtained, and the period is determined according to this ratio. This includes the one that controls filament preheating at t2. In this case, since it is a ratio with its own cold resistance value, the filament temperature is detected in a pseudo manner, and the influence due to the difference in electrical characteristics between the filaments can be made relatively small. In this case, the cold resistance value is measured immediately after the filament preheating is started every time the discharge lamp is turned on (a period in which the filament temperature is not increased or negligible due to preheating). In this case, the cold resistance of the filament can be detected by the resistance detecting means.

  The operation control device controls at least one of the filament current i2 and the supply period t2 in the period t2. In addition to controlling both, the operation control device changes the filament current at a preset change rate in the period t2. Things are also acceptable. Further, the current I1 within the period T1 may be changed at a certain change rate.

  Furthermore, the length relationship between the periods T1 and t2 and the magnitude relationship between the filament currents I1 and i2 can be basically set arbitrarily. However, in order to accurately and safely detect the state of the filament such as the remaining state of the emitter in the first period, a relatively large second filament current is caused to flow by relatively shortening the first period. It was preferable to adjust by passing a relatively small current i2 during the period t2.

  In such a discharge lamp lighting device, the operation control means controls the operation of the lighting device so as to output the filament current I1 during the period T1 when the discharge lamp is started. The filament resistance detection means detects the filament resistance value after the period T1. Then, the operation control means sets the length of the period t2 and / or the filament current i2 in accordance with the filament resistance detection value, and controls the operation of the lighting device so that the set output is obtained.

  According to a second aspect of the present invention, there is provided a variable output lighting device that supplies a filament preheating power and a lighting power to a hot cathode type discharge lamp; current detection means for detecting a current value of the filament; between both ends of the filament Voltage detection means for detecting voltage; and operation control means for controlling the operation of the lighting device so that the output can be changed. The operation control means is configured to detect the resistance of the filament from the detection values of the current detection means and the voltage detection means. A resistance detecting means for detecting a value, a timer means for measuring a filament preheating time, a memory means for storing data such as a preheated filament preheating current value and a supply period, and an arithmetic control means, and a filament. As a preheating period, a period T1 for supplying the filament current I1 and a period t2 for supplying the filament current i2 following the period T1 are set. And at least one of the filament current i2 and the supply period t2 in the period t2 is controlled based on the data stored in the memory means in accordance with the filament resistance detection value of the resistance detection means after the period T1. And

  The invention described in claim 2 specifies the content which is somewhat embodied with respect to the invention described in claim 1. Therefore, the operation and the like are basically the same as those of the first aspect of the invention.

  According to a third aspect of the present invention, in the discharge lamp lighting device according to the first or second aspect of the invention, the operation control device sets the ratio between the filament resistance value after the period T1 detected by the resistance detection means and the cold resistance value of the filament. Accordingly, at least one of the filament current i2 and the supply period t2 in the period t2 is controlled.

  Since the present invention controls the filament current i2 and the supply period t2 in the period t2 according to the ratio between the filament resistance value after the period T1 detected by the resistance detection means and the cold resistance value of the filament, Thus, the filament temperature is detected and the influence of the difference in electrical characteristics between the filaments is relatively reduced.

  4. The lighting device according to claim 4; a lighting fixture main body; a hot cathode type discharge lamp provided in the fixture main body; and the discharge lamp lighting device according to any one of claims 1 to 3 for lighting the discharge lamp. And;

  The lighting device may be indoor or outdoor, and the lighting device may or may not be built in the lighting fixture body.

  According to the first and second aspects of the present invention, the length of the second period t2 and the filament current value even when the filament lamp temperature rises differ depending on the cumulative lighting state of the discharge lamp, that is, the degree of decrease in the emitter, or the type of the discharge lamp. Therefore, it is possible to provide a discharge lamp lighting device that can be started at a more appropriate filament temperature without causing an excessive current to flow through the filament and excessively heating the filament to disconnect it.

  According to the third aspect of the invention, it is possible to reduce the influence of the difference in electrical characteristics between the filaments and to perform more appropriate filament preheating.

  According to invention of Claim 4, the illuminating device which has an effect of the invention in any one of Claim 1 thru | or 3 can be provided.

  Hereinafter, an embodiment of a discharge lamp lighting device of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a lighting device, and FIG. 2 is a flowchart showing the operation of the embodiment.

  In FIG. 1, 1 is a commercial AC power source, and 2 is a rectifier that rectifies the output voltage of the commercial AC power source 1 and smoothes it as necessary. The lighting device 3 converts the output voltage of the rectifying device 2 into, for example, a high frequency voltage higher than an audible frequency, and lights the hot cathode discharge lamp 4. The lighting device 3 of the present embodiment includes a series circuit unit 9 including a switching unit 5, a DC cut capacitor 6, a resonance / current limiting inductor 7 and a resonance / starting capacitor 8 that constitute high frequency generation means. Have. The inductor 7 and the capacitor 8 are supplied with the switching output of the switching unit 5 at least before starting the lighting of the discharge lamp 4 to form a series resonance circuit. Accordingly, the resonance output changes as the output frequency of the switching unit 5 increases or decreases with respect to the natural vibration frequency of the series resonance circuit.

  The resistance detection means 10 has a current detection means 11 for detecting the filament current, a voltage detection means 12 for detecting the voltage between the filaments, and a calculation means 13 for calculating the filament resistance from the detection values of these detection means. Although not shown, the analog / digital conversion means is provided in the preceding stage of the calculation means 13 or is built in the calculation means 13.

  Reference numeral 14 denotes an operation control device of the lighting device 3, and the switching frequency of the switching unit 5 is set so that the preset filament current I1 flows in the filament of the discharge lamp 4 during the first preset period T1 at the start. In addition to the control, after the first period T1, the second period t2 and the filament current i2 are set according to the detection value of the resistance detection means 10, and the output of the switching unit 5 is set so as to be the set filament current i2. Control the frequency. The second period t2 and the filament current i2, which are a combination of a plurality of types associated with the detection by the resistance detection means 10, are set in advance.

  Further, the operation control device 14 performs operation control so that the lighting device 3 outputs a high voltage for starting after the end of the second period t2. That is, by making the output frequency of the switching unit 5 close to the natural vibration frequency of the series resonant circuit of the series circuit unit 9, the starting sequence can be applied to the discharge lamp 4 so that a voltage larger than that during preheating or lighting can be applied. It is configured.

  Next, the operation of this embodiment will be described with reference to FIG. First, when the start of the discharge lamp 4 is started, the operation control device 14 performs control so that the current I1 is supplied to the filament in the first period T1 (S1). Simultaneously with the end of the period T1, the detection value of the resistance detecting means is read, and the period t2 and the filament current i2 are set according to the detection value, and the output frequency of the switching unit 5 is controlled so as to become the filament current i2 (S2). ). When the period t2 ends, the frequency of the switching unit 5 is controlled to be capable of generating a high voltage for starting (S3). Next, the start-up sequence is finished by controlling the frequency to generate a voltage at the time of lighting (S4).

  In order to change the output of the lighting device as in the above steps (S1 to S4), the output frequency is set to (S1) f3 in the inductive region of the resonance output characteristic of the series resonance circuit. → (S2) f4 → (S3) f1 → (S4) f2. Here, the frequency f is assumed to be lower in ascending order of the suffix numbers.

  Further, the discharge lamp lighting device of the present embodiment may have an end-of-life detection function, a discharge lamp mounting detection function, and the like of the discharge lamp 4. In this case, the current detection means 11, the voltage detection means 12, and the operation control means 14 can also be used as a detection / determination part. For example, when the detection value of the current detection means 11 is 0, it can be determined that there is no load. Moreover, when the detection value of the resistance detection means after the first period T1 is abnormally large, it can be determined that the life of the discharge lamp is reached.

  Next, a second embodiment of the discharge lamp lighting device of the present invention will be described with reference to FIGS. 3 is a circuit diagram showing a second embodiment of the discharge lamp lighting device, FIG. 4 is a flowchart showing the operation of the embodiment, and FIG. 5 is a diagram showing a setting example of (Rh / Rc), period t2, and current i2. FIG. 6 shows, for two discharge lamps having different (Rh / Rc), the first period T1, the current I1, the second period t2, the current i2, the starting voltage application, the lighting voltage application state, and the respective discharge lamps. It is a figure which shows the change state of (Rh / Rc) of an electric lamp about period T1 and t2.

  In FIG. 3, the same or corresponding parts as those in FIG. In the present embodiment, the switching unit 5 includes a pair of FETs 51 and 52 that are connected in series to constitute a half-bridge inverter and a drive circuit 53 that alternately turns on and off the FETs 51 and 52.

  The operation control means 14 includes an analog / digital conversion means 143 for analog / digital conversion of detection signals from the memory means 141, timer means 142, current detection means 11 and voltage detection means 12, arithmetic means 144 such as a CPU, and the drive. An interface 145 for transmitting and receiving signals to and from the circuit 53 is provided.

  In this embodiment, the calculation means 144 calculates the filament resistance value, and calculates the filament resistance (cold resistance) immediately after the filament preheating starts every time the discharge lamp 4 is started, and stores the data in the memory. The information is stored in the means 141. And according to the filament resistance value after the first period T1, the second period t2 and the current depend on the ratio (Rh / Rc) of the detected filament resistance (Rh) and cold resistance (Rc). i2 is set.

  Next, the operation of the present embodiment will be described. Note that the second period t2 and the current i2 associated with the ratio (Rh / Rc) of the detected filament resistance (Rh) and cold resistance (Rc) are stored in the memory means 141 in advance. .

  First, when starting of the discharge lamp 4 is started, the operation control means 14 controls the output frequency of the drive circuit 53 so as to supply the filament current I1 to the filament in the first period T1 (S11). Further, the cold resistance (Rc) is calculated from the detection signals of the current detection means 11 and the voltage detection means 12 simultaneously with or immediately after the start of preheating, and is stored in the memory means 141 (S12).

  When the period T1 ends with the time measurement by the timer means 142, the filament resistance value (Rh) at this time is calculated (S13), and the ratio (Rh / Rc) to the cold resistance (Rc) is obtained (S14).

  Next, the second period t2 and the current i2 corresponding to this (Rh / Rc) are read from the memory means 141 and set (S15). As a result, the drive circuit 53 outputs a frequency signal that can supply the current i2. An example of data stored in the memory means 141 is shown in FIG. That is, in FIG. 5, different combinations of period t2 and current i2 are set for (Rh / Rc) of less than 1.5 to 3.0, 3.0 to 4.5, and 4.5 to 6.0. Yes.

  In the present embodiment, when (Rh / Rc) is less than 1.5 or more than 6.0, there is no load such as the filament being broken, or the end-of-life state in which the filament emitter is consumed. It is judged that it does not advance to the subsequent step.

  When the second period t2 ends, the output frequency of the drive circuit 53 is controlled so that a high voltage for starting can be generated (S16). Next, the start-up sequence is completed by controlling the frequency to generate a voltage at the time of lighting (S17).

  FIG. 6 shows two discharge lamps having different (Rh / Rc), each of the first period T1, the current I1, the second period t2, the current i2, the starting voltage application, the lighting voltage application state, and the respective discharge lamps. The change state of the lamp (Rh / Rc) is shown for the first and second periods.

  In FIG. 6, the voltage waveform (a) is an applied voltage waveform to the discharge lamp a having (Rh / Rc) of 2.1, and the voltage waveform (b) is (Rh / Rc) of 3.9. It is the applied voltage waveform with respect to the discharge lamp b. Here, the period T1 was 0.2 sec, and I1 was 1000 mA. Further, each period t2 and current i2 when (Rh / Rc) is 2.1 or 3.9 are as shown in FIG. A curve l1 in FIG. 6 shows a change state of (Rh / Rc) of the discharge lamp a to which the voltage of the waveform (a) is applied. A curve l2 in FIG. 6 shows a change state of (Rh / Rc) of the discharge lamp b to which the voltage of the waveform (b) is applied.

  As is apparent from FIG. 6, even if preheating is performed under the same conditions in the period T1, the (Rh / Rc) of the filament varies depending on the cumulative lighting time of the discharge lamp and the like. However, as in the present invention, by adjusting the current i2 and the length of the period 2 in the period t2, the high voltage for starting is applied when both become equal (Rh / Rc).

  Next, an embodiment of the illumination device will be described with reference to FIG. The lighting device of the present embodiment is a ceiling-mounted lighting fixture. In FIG. 7, 71 is a lighting fixture body, 72 is a socket provided in the lighting fixture body 71, 73 is a reflector, 74 is a hot cathode discharge lamp mounted in the socket 72, and 75 is built in the lighting fixture body 71. This is a discharge lamp lighting device.

  Since the lighting device having such a configuration is started after the hot-cathode discharge lamp 75 is properly preheated, the lamp life is hardly deteriorated, so that the lamp replacement period can be lengthened and the unexpected turn-off is reduced. it can.

Block diagram showing an embodiment of a discharge lamp lighting device Flow chart showing operation of the embodiment Circuit diagram showing a second embodiment of a discharge lamp lighting device Flow chart showing operation of the embodiment The figure which shows the example of a setting of (Rh / Rc), period t2, and electric current i2. For two discharge lamps having different (Rh / Rc), the first period T1, the current I1, the second period t2, the current i2, the starting voltage application, the lighting voltage application state, and the (Rh / Rc) is a diagram showing a change state for periods T1 and t2. The perspective view which shows one Embodiment of an illuminating device

Explanation of symbols

  3, 75: discharge lamp lighting device, 4: hot cathode discharge lamp, 10: resistance detection means, 11: current detection means, 12: voltage detection means, 14: operation control means, 71: luminaire main body.

Claims (4)

A variable output lighting device for supplying filament preheating power to the hot cathode discharge lamp and supplying lighting power;
Resistance detection means for detecting the resistance value of the filament;
The operation is controlled so as to control the output of the lighting device, which includes a period T1 for supplying a filament current I1 as a filament preheating period, a period t2 for supplying a filament current i2 following the period T1, and a period T1 An operation control means for the lighting device for controlling at least one of the filament current i2 and the supply period t2 in the period t2 according to the filament resistance detection value of the subsequent resistance detection means;
A discharge lamp lighting device comprising: A variable output lighting device for supplying filament preheating power to the hot cathode discharge lamp and supplying lighting power;
Current detection means for detecting the current value of the filament;
Voltage detecting means for detecting the voltage across the filament;
An operation control means for controlling the operation of the lighting device so that the output can be changed;
Comprising
The operation control means includes a resistance detection means for detecting a resistance value of the filament from detection values of the current detection means and the voltage detection means, a timer means for measuring a filament preheating time, a filament preheating current value input in advance and a supply A memory means for storing data such as a period and an arithmetic control means are provided, and a period T1 for supplying a filament current I1 as a filament preheating period and a period t2 for supplying a filament current i2 following the period T1 are set. The at least one of the filament current i2 and the supply period t2 in the period t2 is controlled based on the data stored in the memory means according to the filament resistance detection value of the resistance detection means after the period T1. Electric light lighting device.   The operation control device controls at least one of the filament current i2 and the supply period t2 in the period t2 according to the ratio of the filament resistance value after the period T1 detected by the resistance detection means and the cold resistance value of the filament. The discharge lamp lighting device according to claim 1, wherein the discharge lamp lighting device is provided. A lighting fixture body;
A hot cathode type discharge lamp provided in the luminaire body;
The discharge lamp lighting device according to any one of claims 1 to 3, wherein the discharge lamp is energized;
An illumination device comprising:

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