JP4922838B2 - Fluorescent lamp abnormality detection device - Google Patents

Description

  The present invention relates to a fluorescent lamp abnormality detection apparatus, and more particularly to an apparatus for detecting a so-called flicker state in which the lighting frequency of a fluorescent lamp driven by an AC power supply is lower than that in a normal state.

  As this type of fluorescent lamp abnormality detection device, for example, a technique described in Patent Document 1 has been proposed. In the technique described in Patent Document 1, a current detector is provided in an AC power supply circuit of a fluorescent lamp used for lighting in an elevator car, and an abnormality of the fluorescent lamp is detected from a peak value of a measured current measured by the current detector. It is like that.

Specifically, it is determined that the fluorescent lamp has deteriorated when the difference between adjacent positive and negative peak values of the measurement current exceeds a predetermined first reference value, and the adjacent positive and negative peaks of the measurement current are determined. When the value difference exceeds a predetermined second reference value, it is determined that the fluorescent lamp is in a so-called flickering state. Further, when the difference between the positive peak value of the current when the fluorescent lamp is normal and the positive peak value of the measured current exceeds a predetermined third reference value, the glow lamp is cut or the fluorescent lamp is cut. It comes to judge.
JP-A-10-261492

  In the technique described in Patent Document 1, for example, a voltage drop occurs due to an elevator moving cable that supplies electric power to a fluorescent lamp. Therefore, it is necessary to consider fluctuations in the power supply voltage of the fluorescent lamp due to the voltage drop. In addition to having to set each reference value above, and indirectly monitoring the lighting state of the fluorescent lamp with the above measurement current, the process of detecting an abnormality of the fluorescent lamp becomes complicated, Misdetection is likely to occur, which is not preferable.

  The present invention has been made in view of the above problems, and can directly and accurately detect an abnormality of a fluorescent lamp by directly monitoring the lighting state of the fluorescent lamp with an optical sensor. The object is to provide a detection device.

  The invention according to claim 1 is a fluorescent lamp abnormality detecting device for detecting an abnormality of a fluorescent lamp driven by an AC power source, wherein the optical sensor receives light from the fluorescent lamp, and a quarter cycle of the AC power source. Sampling means for outputting a lighting signal or a non-lighting signal in accordance with the output signal of the light sensor each time, and an abnormality detection means for detecting an abnormality of the fluorescent lamp based on the output of the sampling means. It is a feature.

  That is, in the invention according to claim 1, since the fluorescent lamp is turned on every half cycle of the AC power supply in a normal lighting state and is turned on and off every quarter cycle of the AC power supply, sampling is performed. The means outputs a lighting signal or a non-lighting signal according to the output value of the optical sensor every quarter cycle of the AC power source, so that the fluorescent lamp normally turns on and off normally every quarter cycle of the AC power source. The abnormality detection means can determine whether or not the fluorescent lamp is in a state.

  Then, as in the invention described in claim 2, the sampling means shapes the waveform of the AC power supply and generates a clock pulse generated every quarter cycle of the AC power supply, and an output signal of the optical sensor. If the lighting signal or the non-lighting signal is output according to the above, the abnormality detecting means can more reliably determine the lighting state of the fluorescent lamp every quarter cycle of the AC power supply. become.

  Specifically, the sampling means may compare the output signal of the optical sensor with the clock pulse every quarter cycle of the AC power supply, and output a lighting signal or a non-lighting signal according to the result.

  In addition, according to the invention of claim 3, the sampling means outputs a lighting signal when both the output signal of the optical sensor and a clock pulse are present, while the output signal of the optical sensor and the clock are output. A function of outputting a non-lighting signal when any one of the pulses is present, and the abnormality detecting means determining the state of the fluorescent lamp according to the input state of the lighting signal and the non-lighting signal It is characterized by having.

  In the invention of claim 3, when the clock pulse exists and the fluorescent lamp is lit, the sampling means outputs a lighting signal, while the clock pulse exists and the fluorescent lamp is When the light is turned off, the sampling means outputs a non-lighting signal. That is, the sampling means outputs a lighting signal or a non-lighting signal in synchronization with the clock pulse generated every quarter cycle of the AC power supply.

  According to a fourth aspect of the present invention, when the abnormality detection unit receives a plurality of non-lighting signals after a lighting signal is input, and further receives a lighting signal, the fluorescent lamp If it is determined that the flicker state is present, it is desirable to detect the flicker state at the initial stage of the flickering state of the fluorescent lamp, that is, the stage that cannot be perceived by humans.

  Further, as in the invention described in claim 5, when the lighting signal is continuously input in the adjacent quarter cycle of the AC power source, the abnormality detection means is configured to detect the light sensor from outside the fluorescent lamp. If it is determined that light is received, malfunction due to the influence of light from outside the fluorescent lamp can be prevented.

  According to the first to fifth aspects of the present invention, the abnormality of the fluorescent lamp is directly detected based on the output of the optical sensor that receives light from the fluorescent lamp, and the abnormality detecting means includes Since the abnormality of the fluorescent lamp is detected based on the lighting signal and the non-lighting signal output by the sampling means every quarter cycle of the AC power source, the abnormality of the fluorescent lamp can be detected easily and accurately.

  According to the second aspect of the present invention, the sampling means outputs a lighting signal or a non-lighting signal in accordance with a clock pulse generated every quarter cycle of the AC power supply and an output signal of the optical sensor. Therefore, the abnormality detection means can more reliably determine the lighting state of the fluorescent lamp every quarter cycle of the AC power supply.

  According to a third aspect of the present invention, the sampling means outputs a lighting signal or a non-lighting signal in synchronization with a clock pulse generated every quarter cycle of the AC power supply, so that the abnormality detecting means is fluorescent. It becomes possible to detect the abnormality of the lamp more reliably.

  According to the invention described in claim 4, it is possible to detect a flickering state at a stage where the fluorescent lamp cannot be perceived by humans. In addition to preventing discomfort caused by the flickering state of the fluorescent lamp, there is an advantage that the life of the fluorescent lamp can be easily and reliably determined by detecting the flickering state.

  According to the fifth aspect of the present invention, malfunction due to the influence of light from outside the fluorescent lamp can be prevented, and the reliability of the operation can be improved.

  FIG. 1 is a block diagram showing a fluorescent lamp abnormality detecting device as a more specific embodiment of the present invention.

  As shown in FIG. 1, a fluorescent lamp 1 for illuminating the interior of an elevator car is driven by an AC power supply 2, and waveform shaping means for shaping a waveform of the AC power supply 2 and outputting a clock pulse. The waveform shaping circuit 3 is connected in parallel with the AC power source 2.

  On the other hand, a photodiode 4 as an optical sensor that receives light from the fluorescent lamp 1 is disposed in the vicinity of the fluorescent lamp 1, and a sampling circuit 5 as a sampling means for sampling an output signal of the photodiode 4 serves as the photodiode 4. An abnormality detection circuit 7 is connected to the sampling circuit 5 as an abnormality detection means for detecting an abnormality of the fluorescent lamp 1 based on the output of the sampling circuit 5.

  FIG. 2 is a diagram showing the relationship between the voltage waveform of the AC power source 2 and the output signal of the photodiode 4 when the fluorescent lamp 1 is normally lit. FIG. 2B shows the waveform of the signal, and FIG. 2B shows the voltage waveform of the AC power source 2.

  Here, in the state in which the fluorescent lamp 1 is normally lit, as shown in FIGS. 2A and 2B, while the fluorescent lamp 1 is lit when the positive / negative peak voltage of the AC power source 2 is generated, When the AC power supply 2 is at zero voltage, the fluorescent lamp 1 is turned off, and the lighting frequency of the fluorescent lamp 1 is twice the frequency of the AC power supply 2.

  FIG. 3 is an explanatory diagram showing the operation of the waveform shaping circuit 3. FIG. 3 (a) shows the voltage waveform of the AC power supply 2, and FIG. 3 (b) shows the frequency of the waveform shown in FIG. 3 (a). (C) of FIG. 3 shows the waveform of the clock pulse output from the waveform shaping circuit 3, respectively.

  Specifically, the waveform shaping circuit 3 has a frequency multiplier 3a, and the frequency multiplier 3a doubles the frequency of the power supply voltage waveform A of the AC power supply 2 shown in FIG. The waveform is shaped into an intermediate waveform B shown in FIG. Then, the intermediate waveform B is compared with a predetermined reference value by the comparator 3b and A / D converted to obtain a clock waveform C shown in FIG. That is, the waveform shaping circuit 3 sends the clock pulses generated to the sampling circuit 5 and the abnormality detection circuit 7 every quarter cycle of the AC power supply 2, that is, approximately when the AC power supply 2 generates positive and negative peak voltages and zero voltage. ing.

  FIG. 4 is a diagram showing a time chart of the sampling circuit 5 when the fluorescent lamp 1 is in a normal lighting state.

  The sampling circuit 5 includes a flip-flop 5a that operates in synchronization with the clock pulse. As shown in FIG. 4, the flip-flop 5a includes the clock pulse from the waveform shaping circuit 3, that is, the clock input, and the photodiode 4. When the output signal from, that is, the data input is input together, “1”, that is, the high level voltage is input as the lighting signal, and only one of the clock pulse from the waveform shaping circuit 3 and the output signal from the photodiode 4 is input. In this case, “0” as a non-lighting signal, that is, a low level voltage is output to the abnormality detection circuit 7 as a digital signal.

  Note that, as described above, in the normal lighting state of the fluorescent lamp 1, the fluorescent lamp 1 is turned on every half cycle of the AC power supply 2 and is turned on and off alternately every quarter cycle of the AC power supply 2. The sampling circuit 5 alternately outputs “1” and “0” every quarter period of the AC power source 2, that is, every time a clock pulse is input.

  The output from the sampling circuit 5 is input to the abnormality determination unit 7b via the shift register 7a operating in synchronization with the clock pulse in the abnormality detection circuit 7, and the abnormality determination unit 7b is set to “1” and “0”. The state of the fluorescent lamp 1 is determined according to the input situation. Moreover, the abnormality determination part 7b has a data communication function, and when the abnormality determination part 7b detects abnormality of the fluorescent lamp 1, it reports to the monitoring center 8 through a telephone line.

  In the fluorescent lamp abnormality detection apparatus configured as described above, the abnormality determination unit 7b determines the state of the fluorescent lamp 1 at a predetermined time. As described above, when the fluorescent lamp 1 is normally lit, the sampling circuit 5 alternately outputs “1” and “0” every quarter cycle of the AC power supply 2, so that the abnormality determination unit 7 b performs sampling. When the circuit 5 outputs “1” and “0” alternately, it is determined that the fluorescent lamp 1 is normal. For example, when “10101010101” is input to the abnormality determination unit 7b, the abnormality determination unit 7b determines that the fluorescent lamp 1 is normal.

  On the other hand, when the fluorescent lamp 1 deteriorates with time and approaches its life, the lighting frequency of the fluorescent lamp 1 is lower than that in the normal lighting state, and the fluorescent lamp 1 enters a so-called flickering state. When the fluorescent lamp 1 is in the flickering state, after “1” is input from the sampling circuit 5 to the abnormality detection circuit 7, a plurality of “0” s are continuously input, and further “1” is input. Therefore, in this case, the abnormality determination unit 7b determines that the fluorescent lamp 1 is in the flickering state. That is, for example, when “10001000001” is input to the abnormality determination unit 7b, the abnormality determination unit 7b determines that the fluorescent lamp 1 is in the flicker state, and the initial stage of the flicker state of the fluorescent lamp 1, That is, a flickering state that cannot be perceived by humans is detected.

  Also, the abnormality determination unit 7b counts the number of times “0” is continuously input, and when the number of times “0” is continuously input exceeds a predetermined value, abnormality determination The part 7b determines that the bulb of the fluorescent lamp 1 is broken or an abnormality has occurred in the photodiode 4 itself. For example, when “00000000000000” is input to the abnormality determination unit 7b, the abnormality determination unit 7b determines that the bulb of the fluorescent lamp 1 has run out or an abnormality has occurred in the photodiode 4 itself.

  Further, when the abnormality detection circuit 7 continuously inputs “1” from the sampling circuit 5 in the adjacent quarter cycle of the AC power supply 2, the abnormality determination unit 7 b causes the photodiode 4 to emit light from other than the fluorescent lamp 1. Judge that it is receiving light. For example, when “11111111111” is input to the abnormality determination unit 7 b, the abnormality determination unit 7 b determines that the photodiode 4 receives light from other than the fluorescent lamp 1.

  When there is an abnormality in the fluorescent lamp 1 or the photodiode 4, the abnormality determination unit 7b notifies the monitoring center 8 of the content of the abnormality, and when the monitoring center 8 receives the notification from the abnormality detection circuit 7, For example, necessary measures such as dispatching workers to replace the fluorescent lamp 1 are taken.

  Therefore, according to the present embodiment, based on the output of the photodiode 4 that receives light from the fluorescent lamp 1, the bulb break of the fluorescent lamp 1 and the flickering state are directly detected. Since the abnormality detection circuit 7 detects the abnormality of the fluorescent lamp 1 based on the digital signal output from the sampling circuit 5, the abnormality of the fluorescent lamp 1 can be detected easily and accurately.

  In addition, the flickering state of the fluorescent lamp 1 can be detected at an early stage at a stage that cannot be perceived by humans so that the life of the fluorescent lamp 1 can be easily determined and the fluorescent lamp 1 can be replaced at that stage. It is possible to prevent the user from feeling uncomfortable due to the flickering state of the fluorescent lamp 1.

  Further, there is a merit that the abnormality of the photodiode 4 itself and the fact that the photodiode 4 receives light from other than the fluorescent lamp 1 can be detected and the reliability of the operation can be improved.

  Needless to say, the present invention can also be applied to so-called inverter-type fluorescent lamps as in this embodiment.

The block diagram which shows the fluorescent lamp abnormality detection apparatus as embodiment of this invention. It is a figure which shows the relationship between the voltage waveform of AC power supply in FIG. 1, and the output signal of a photodiode, The figure (a) is a figure which shows the output signal waveform of a photodiode, The figure (b) is the voltage of AC power supply. The figure which shows a waveform. It is explanatory drawing which shows operation | movement of the waveform shaping circuit in FIG. 1, Comprising: The figure (a) is a figure which shows the voltage waveform of AC power supply, The figure (b) has shown the frequency of the waveform shown to the figure (a) 4. The figure which shows the multiplied intermediate waveform, The figure (c) is a figure which shows the clock pulse which a waveform shaping circuit outputs. The time chart of the flip-flop in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fluorescent lamp 2 ... AC power supply 4 ... Photodiode (light sensor)
5 ... Sampling circuit (sampling means)
7. Abnormality detection circuit (abnormality detection means)

Claims (5)

A fluorescent lamp abnormality detection device for detecting an abnormality of a fluorescent lamp driven by an AC power source,
An optical sensor for receiving light from the fluorescent lamp;
Sampling means for outputting a lighting signal or a non-lighting signal according to the output signal of the photosensor every quarter cycle of the AC power supply;
An abnormality detecting means for detecting an abnormality of the fluorescent lamp based on the output of the sampling means;
A fluorescent lamp abnormality detection device comprising:   The sampling means shapes the waveform of the AC power supply and outputs a lighting signal or a non-lighting signal according to the clock pulse generated every quarter cycle of the AC power supply and the output signal of the photosensor. The fluorescent lamp abnormality detecting device according to claim 1, wherein:   The sampling means outputs a lighting signal when both the output signal and clock pulse of the optical sensor are present, and is not lit when either one of the output signal and clock pulse of the optical sensor is present. A signal is output, and the abnormality detection means has a function of determining the state of the fluorescent lamp in accordance with the input status of a lighting signal and a non-lighting signal. Fluorescent lamp abnormality detection device described in 1.   The abnormality detection means is configured to determine that the fluorescent lamp is in a flickering state when a plurality of non-lighting signals are continuously input after a lighting signal is input and further a lighting signal is input. The fluorescent lamp abnormality detection device according to claim 3.   The abnormality detecting means determines that the light sensor is receiving light from outside the fluorescent lamp when a lighting signal is continuously input in adjacent quarter periods of the AC power supply. The fluorescent lamp abnormality detection device according to claim 4, wherein

Images