JPH076696A - Fluorescent lamp inspection device - Google Patents

Abstract

PURPOSE:To provide a fluorescent lamp inspection device stable without generation of erroneous inspection even when generated a disturbance due to the sunlight. CONSTITUTION:A fluorescent lamp inspection device has an antenna 14 positioned in the vicinity of a lead wire 12 of a filament 13 of a fluorescent lamp 11 to make electroluminescence of the fluorescent lamp 11 by a high frequency power supply 16 and a light receiving element 23 for detecting light intensity of the light emitting fluorescent lamp 11. The device has a low frequency oscillating part 19 and an amplitude modulating part 20 for giving prescribed low frequency information relating to a high frequency and a high-pass filter 25 for removing a low frequency component from an output of the light receiving element 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp inspection device used in a fluorescent lamp production process. More specifically, impurity gas such as air in the fluorescent lamp is sufficiently replaced with an inert gas such as argon. The present invention relates to a fluorescent lamp inspecting device for inspecting whether or not the fluorescent lamp is inspected.

[0002]

2. Description of the Related Art Conventionally, in a method of manufacturing a fluorescent lamp,
At both ends of the bulb with a phosphor coating on the inner surface of the lamp, an unsealed tube formed by sealing a filament coated with a carbonate of an alkaline earth metal is heated while exhausting to remove adsorbed impurities. Further, while heating, evacuation is continued to decompose and activate the impurities of the emitter liquid adhered to the filament, and then the inert gas such as argon gas is filled and sealed. Here, if impurity gas such as air remains, or if there is air damage in the fluorescent lamp due to damage such as cracks in the fluorescent lamp, the fluorescent lamp cannot be lit at all or only weakly. There's a problem. Further, there is a problem that the life is shortened because the filament is oxidized by the residual air.

In order to solve the problem, conventionally, after filling with argon gas, it was inspected whether impurities such as air were mixed. In other words, by taking advantage of the fact that a fluorescent lamp with sufficiently exhausted impure gas can be lit by high-frequency radio waves, the fluorescent lamp can be inspected in a short time and in a non-contact manner in the automatic assembling process of the fluorescent lamp. There is. The configuration of a conventional fluorescent lamp inspection is shown in FIG. The fluorescent lamp 11 has already been purged of impure gas such as air and is filled with argon gas. Filaments 13 are fixed to both ends of the fluorescent lamp 11. Filament 1
Both ends of 3 are exposed to the outside of the fluorescent lamp 11 as lead wires 12.

The vicinity of the lead wire 12 and the lead wire 12
An antenna 14 is attached to a position where it does not come into contact with the antenna. A cable 21 is connected to the antenna 14. The other end of the cable 21 is connected to the high frequency power supply 16. The high frequency power supply 16 is a high frequency oscillator 1 that oscillates a high frequency F1.
7 and a power increasing unit 18. An optical fiber 15 is attached to a position facing the light emitting portion of the fluorescent lamp. The optical fiber 15 is connected to the light receiver 22.
The light receiver 22 includes a light receiving element 23, which is a photodetector, and an amplifier 2.
4 and a comparator 27 for comparing the output of the light receiver with a threshold value.

Next, the operation of the conventional fluorescent lamp inspection device having the above structure will be described. The high frequency power supply 16 creates a high frequency of a high frequency F1 suitable for lighting the fluorescent lamp 11 in the high frequency oscillation unit 17, amplifies the output power by the power amplification unit 18, and the antenna 1 via the cable 21.
The high frequency voltage shown in FIG. Here, as the high frequency F1, several MHz to 20 MHz is used. The antenna 14 receives the high frequency voltage,
It oscillates radio waves of high frequency F1. In the case of a non-defective fluorescent lamp in which the impure gas such as air in the lamp is sufficiently replaced with argon gas, as shown in FIG. 7B, the fluorescent lamp 1
1 emits light continuously. Further, in the case of a defective fluorescent lamp in which a large amount of impure gas such as air remains in the lamp due to cracking of the lamp, it does not emit light as shown in FIG. 7 (c). By detecting this difference with a photodetector, the quality of the fluorescent lamp was inspected.

[0006]

However, the conventional fluorescent lamp manufacturing apparatus has the following problems. (1) The manufacturing process of the fluorescent lamp 11 is often placed in an ordinary factory, and there is ambient light K such as sunlight as shown by the waveform in FIG. 7D. Therefore, the optical fiber 15
The light input from the fluorescent lamp 11 is the light emission I and the ambient light K.
And the sum. The light input to the optical fiber 15 is input to the light receiving element 23 of the light receiver 22 and converted into an electric signal.
When the fluorescent lamp 11 is a non-defective product, the electric signal is as shown in FIG. 8A, and when the fluorescent lamp 11 is a defective product, it is as shown in FIG. 8B.

The electric signal is amplified by the amplifier 24,
The comparator 27 compares it with a threshold value and binarizes it. FIG. 8C shows the output of the comparator 27 when the fluorescent lamp 11 is a good product, and FIG. 8D shows the output of the comparator 27 when the fluorescent lamp 11 is a defective product. As described above, the presence of the ambient light K may cause a defective product to be mistaken for a good product for inspection. Preventing this erroneous inspection is difficult because the sunlight, which is the ambient light K, changes throughout the day and also changes depending on the weather.
Further, it is not realistic to completely shut off the sunlight because it costs electricity and costs are increased.

(2) Conventionally, the light intensity of the fluorescent lamp 11 has been increased by filling the fluorescent lamp 11 with mercury vapor. In recent years, when the defective fluorescent lamp 11 is discarded, it is a problem that the mercury vapor filled in the interior is released to the atmosphere, which causes environmental pollution. In order to solve the problem, a mercury capsule is adhered to the filament, and only the fluorescent lamp 11 which is judged to be a non-defective one by the inspection of the fluorescent lamp 11 is heated by a constant current to melt the mercury capsule to generate mercury. The method of generating steam is adopted.

Therefore, since the fluorescent lamp 11 inspected by the fluorescent lamp inspection device is not filled with mercury vapor, the light intensity of the fluorescent lamp 11 turned on by the high frequency electroluminescence is higher than that of the conventional one. weak. for that reason,
The incidence of false inspections of fluorescent lamp inspection devices was high. Further, when an erroneous inspection occurs in the fluorescent lamp inspection device, it is necessary to remove the mercury vapor generated in the subsequent process and then discard the mercury vapor. Therefore, the occurrence of the erroneous inspection significantly deteriorates the overall production efficiency.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a stable fluorescent lamp inspection device which does not cause an erroneous inspection even when there is a disturbance due to sunlight. .

[0011]

In order to achieve this object, a fluorescent lamp inspection apparatus of the present invention comprises an antenna located near a lead wire of a filament of a fluorescent lamp and having a high frequency power source for causing the fluorescent lamp to emit light by electroluminescence. A fluorescent lamp inspection device having a photodetector for detecting the light intensity of a fluorescent lamp that emits light, comprising: low frequency information giving means for giving predetermined low frequency information to a high frequency; and output of the photodetector. It has a high-pass filter that removes low frequency components from. Further, the fluorescent lamp inspection device has a low-pass filter that removes high frequency components from the output of the photodetector.

In the above fluorescent lamp inspection apparatus, the low frequency information giving means is an amplitude modulation means for performing a predetermined low frequency amplitude modulation on a high frequency. Further, in the above fluorescent lamp inspection device, the low frequency information giving means is a switching means for switching a high frequency at a predetermined low frequency.

[0013]

The antenna of the fluorescent lamp inspection device of the present invention comprising the above means is positioned near the lead wire of the filament of the fluorescent lamp and receives a high frequency voltage from a high frequency power source,
The fluorescent lamp is electroluminescent. Further, the photodetector detects the light intensity of the fluorescent lamp that is emitting light. Further, the low frequency information giving means gives predetermined low frequency information to the optical high frequency. For example, the amplitude modulation unit amplitude-modulates a high frequency with a cycle of the low frequency F2. As another example, the switching unit switches a high frequency in a cycle of the low frequency F2.

The photodetector converts the light intensity emitted by the fluorescent lamp into a voltage signal. The high pass filter removes low frequency components from the output voltage of the photodetector. This allows
It is possible to remove the sunlight component which is a linear component and the general illumination component which is 50 Hz or 60 Hz. The low pass filter also removes high frequency components from the output of the photodetector. As a result, the high frequency component required for electroluminescence can be removed. The comparator binarizes the voltage signal that has passed through the high pass filter and the low pass filter. Further, the off-delay timer delays the off-timing of the binarized voltage signal,
The determination output S of good or bad of the fluorescent lamp is made constant.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fluorescent lamp inspection apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of the fluorescent lamp inspection device. Filaments 13 are fixed to both ends of the fluorescent lamp 11. Both ends of the filament 13 are lead wires 1
2 is outside the fluorescent lamp 11. That is,
The fluorescent lamp 11 has a glass end mount 29 shown in FIG.
Are welded and configured. In the end mount 29,
A pair of lead wires 12 penetrates, and a filament 13 is connected to the tip ends of the pair of lead wires 12. At the center of the end mount 29, a glass tube 31 for gas exchange for exhausting an impure gas such as air and filling the gas with argon gas.
Are formed.

The gas exchange glass tube 31 evacuates the air in the fluorescent lamp 11 to fill it with argon gas. After filling with argon gas, the glass tube 31 for gas exchange is
Fused near the end mount 29. This allows
The fluorescent lamp 11 is in a state where impure gas such as air is removed and argon gas is filled. Further, the other ends of the pair of lead wires 12 are in a state of protruding outside the fluorescent lamp 11. The vicinity of the lead wire 12 and the lead wire 12
An antenna 14 is attached to a position where it does not come into contact with the antenna. The cable 21 is connected to the antenna 21. The other end of the cable 21 is connected to the high frequency power supply 16.

The high frequency power supply 16 includes a high frequency oscillating section 17 for oscillating a high frequency F1, a power increasing section 18 for generating a high voltage for radio wave oscillation in the antenna 14, a low frequency oscillating section 19 for oscillating a low frequency F2, and a low frequency. An amplitude modulation unit 20 for amplitude-modulating a high frequency by the frequency F2. Further, an optical fiber 15 is attached at a position facing the light emitting portion of the fluorescent lamp 11. The optical fiber 15 is connected to the light receiver 22. The photodetector 22 is a photodetector 23 which is a photodetector for converting light energy into electric energy, an amplifier 24 for amplifying the electric signal, a high-pass filter 25 for removing low frequency components of the electric signal,
A low-pass filter 26 for removing high frequency components of an electric signal, a comparator 2 for comparing an output value with a threshold value
7 and an off-delay timer 28 for delaying the off-timing of the output of the comparator 27 for a fixed time.

Next, the operation of the fluorescent lamp inspecting apparatus of this embodiment having the above construction will be described. The high frequency power supply 16 oscillates a high frequency of high frequency F1 = several MHz to 20 MHz suitable for lighting the fluorescent lamp 11 in the high frequency oscillating unit 17, and outputs it to the power amplifying unit 18. In this embodiment, F
1 = 13 MHz. The low frequency oscillating unit 19 oscillates a low frequency of low frequency F2 = 1 to 2 KHz and outputs it to the amplitude modulating unit 20. In particular, the low frequency F2 should be set to around 1 KHz. This is because the high-pass filter 25 and the low-pass filter 26 have good performance around 1 KHz. In this embodiment, the low frequency F2 = 1 KHz is used. The amplitude modulator 20 performs amplitude modulation on the high frequency, and the power amplifier 18 amplifies the amplitude modulated high frequency and outputs the amplified high frequency to the antenna 14 via the cable 21.

FIG. 2A shows an output waveform of the high frequency power source 16 to the antenna 14. High frequency waveform is low frequency F2
It can be seen that the amplitude is modulated corresponding to. Antenna 14
Oscillates a radio wave having amplitude fluctuation corresponding to the low frequency F2 toward the lead wire 12 in a cycle corresponding to the amplitude-modulated high frequency F1. In the case of a non-defective fluorescent lamp in which an impure gas such as air in the lamp is sufficiently replaced with argon gas, the fluorescent lamp 11 periodically emits light at a low frequency F2 cycle as shown in FIG. . Further, in the case of a defective fluorescent lamp in which a large amount of impure gas such as air remains in the lamp due to cracking of the lamp, it does not emit light as shown in FIG. 2 (c).

Also in the manufacturing process of the fluorescent lamp 11 of this embodiment,
It is placed in an ordinary factory, and there is disturbance light K such as sunlight as shown by the waveform in FIG. Therefore, the light input from the optical fiber 15 is the light emission I of the fluorescent lamp 11.
And the ambient light K. The light input to the optical fiber 15 is input to the light receiving element 23 of the light receiver 22, and the intensity of light energy is converted into a voltage signal. When the fluorescent lamp 11 is a non-defective product, the voltage signal is as shown in FIG. Further, when the fluorescent lamp 11 is a defective product, only the ambient light K is present, so that the result is as shown in FIG.

The voltage signal is amplified by the amplifier 24 and output to the high pass filter 25. The high pass filter 25 removes a component of a frequency lower than the low frequency F2 by a predetermined level. In this embodiment, the low frequency F2 = 1 KHz
On the other hand, the setting value of the high pass filter 25 is 0.9 KH
z, and low frequencies below 0.9 KHz including the linear component are removed. The main component of the ambient light K is sunlight, which is a frequency component that can be said to be almost a straight line, and the frequency of general illumination is 50 Hz or 60 Hz. Therefore, most of the ambient light K is removed by the high-pass filter 25. . Next, the low-pass filter 26 removes frequency components having a predetermined level higher than the low frequency F2. In this embodiment,
Low-pass filter 26 for low frequency F2 = 1 KHz
Is 1.1 KHz, and high frequencies of 1.1 KHz or higher including the high frequency component F1 are removed.

As a result, when the fluorescent lamp 11 is a good product, only the frequency component around the low frequency F2 remains, as shown in FIG. 3 (e). If the fluorescent lamp 11 is defective, the output is 0. Next, this signal is binarized by the comparator 27 as shown in FIG. Then, the off-delay timer 28 that delays the off-timing of the pulse continuously outputs the signal as shown in FIG. As a result, a continuous signal is output as the determination signal S, as shown in (g) of FIG. If the determination signal S is on, a predetermined voltage is applied to the filament 13 to heat the mercury capsule and generate mercury vapor.

As described in detail above, according to the fluorescent lamp inspection apparatus of the present invention, the high frequency power source having the high frequency F1 for electroluminescence causes the low frequency F2 = 1 KHz.
Since the detected light intensity voltage signal of the fluorescent lamp 11 is applied to the high-pass filter 25, the information of the disturbance light K such as sunlight can be removed. Therefore, the disturbance light K such as sunlight exists. However, the fluorescent lamp 11 can be inspected reliably and stably. In addition, the light receiving element 2
3. Even if the performance of the amplifier 24 or the like changes due to temperature, season, aging, and the like, the inspection is performed with a margin, so that it is not necessary to frequently adjust the light receiver 22 and the like. Therefore, defective products can be reliably excluded, and thus the defective fluorescent lamp 1
No mercury vapor is generated in the chamber 1, mercury vapor is not discharged to the outside, and environmental pollution can be prevented. Further, since the low-pass filter 26 is further applied, high frequency components are removed, so that the determination by the comparator 27 becomes easy, and it is possible to reliably and stably determine whether the fluorescent lamp 11 is good or bad.

Next, a second embodiment of the present invention will be described. Since the schematic configuration of the fluorescent lamp inspection device is the same as that of the first embodiment, only different points will be described. FIG. 5 is a block diagram showing the configuration of the high frequency power supply 16. The high frequency power source 16 is
It is composed of a high-frequency oscillator 17 that oscillates a high frequency F1, a switching unit 30 that performs switching at a low frequency F2, and a power booster 18 that generates a high voltage for radio wave oscillation in the antenna 14.

Next, the operation of the fluorescent lamp inspection apparatus of the second embodiment having the above construction will be described. High frequency power supply 16
Oscillates a high frequency of high frequency F1 = 10 MHz suitable for turning on the fluorescent lamp 11 in the high frequency oscillating section 17, and outputs it to the power amplifying section 18. Switching unit 30
Switches at a low frequency F2 = 1 KHz. Therefore, the power amplifier 18 outputs a high frequency wave that is switching-modulated at the low frequency F2. Power amplifier 1
Reference numeral 8 amplifies the switching-modulated high frequency and outputs it to the antenna 14 via the cable 21.

FIG. 5B shows an output waveform of the high frequency power source 16 to the antenna 14. High frequency waveform is low frequency F2
It can be seen that the switching modulation is performed corresponding to. The antenna 14 oscillates a radio wave having an on / off timing corresponding to the low frequency F2 toward the lead wire 12 in a cycle corresponding to the switching modulated high frequency F1. Therefore, the fluorescent lamp 11 repeats light emission in the cycle of the low frequency F2. The method of detecting and processing the light emission of the fluorescent lamp 11 is the same as that of the first embodiment, and thus detailed description thereof will be omitted.

As described above, according to the second embodiment, the emission of the fluorescent lamp 11 can be simplified as compared with the case where the amplitude modulation is performed, so that even in the presence of the ambient light K, it can be reliably and stably performed. It is possible to inspect whether the fluorescent lamp 11 is good or bad.

The present invention is not limited to the above-mentioned embodiment, and various developments are possible. In this embodiment, the high-pass filter and the low-pass filter are individually configured, but
One bandpass filter may be used. Further, in the present embodiment, the output voltage signal is processed as an analog amount, but it is also possible to perform A / D conversion and process as a digital amount by a digital filter.

[0029]

As is apparent from the above description, according to the fluorescent lamp inspection apparatus of the present invention, there is provided an antenna located near the lead wire of the filament of the fluorescent lamp to cause the fluorescent lamp to emit light by electroluminescence from a high frequency power source. In a fluorescent lamp inspection device having a photodetector for detecting the light intensity of a fluorescent lamp which is emitting light, a low frequency information giving unit for giving a predetermined low frequency information to a high frequency, and a high frequency from an output of the photodetector. Since it has a high-pass filter that eliminates frequency components, it can reliably and stably inspect the quality of fluorescent lamps because the component information of ambient light can be reliably removed even in the presence of ambient light such as sunlight. can do. Further, even when mercury vapor is not present, the emission of the fluorescent lamp can be reliably inspected, so that mercury vapor is not generated in defective products, and the cause of environmental pollution can be eliminated.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a fluorescent lamp inspection device that is a first embodiment of the present invention.

FIG. 2 is a first explanatory diagram showing a signal waveform of the fluorescent lamp inspection device.

FIG. 3 is a second explanatory diagram showing a signal waveform of the fluorescent lamp inspection device.

FIG. 4 is a plan view showing a configuration of an end element of a fluorescent lamp.

FIG. 5 is a block diagram showing a configuration of a main part of a fluorescent lamp inspection device according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a conventional fluorescent lamp inspection device.

FIG. 7 is a first explanatory diagram showing a signal waveform of a conventional fluorescent lamp inspection device.

FIG. 8 is a second explanatory diagram showing a signal waveform of a conventional fluorescent lamp inspection device.

[Explanation of symbols]

 11 Fluorescent Lamp 12 Lead Wire 13 Filament 14 Antenna 17 High Frequency Oscillator 18 Power Amplifier 19 Low Frequency Oscillator 20 Amplitude Modulator 23 Photoreceptor 25 High Pass Filter 26 Low Pass Filter 27 Comparator 28 Off Delay Timer 30 Switching Unit

Claims (4)

[Claims] 1. A fluorescent lamp having an antenna located in the vicinity of a lead wire of a filament of the fluorescent lamp for electroluminescence of the fluorescent lamp by a high frequency power source, and a photodetector for detecting the light intensity of the fluorescent lamp which is emitting light. A fluorescent lamp inspection device, comprising: a low-frequency information giving unit that gives predetermined low-frequency information to the high frequency; and a high-pass filter that removes low-frequency components from the output of the photodetector. 2. The fluorescent lamp inspection device according to claim 1, further comprising a low-pass filter that eliminates high-frequency components from the output of the photodetector. 3. The fluorescent substance according to claim 1 or 2, wherein the low frequency information giving unit is an amplitude modulating unit that applies amplitude modulation of a predetermined low frequency to a high frequency. Lamp inspection device. 4. The fluorescent lamp inspection device according to claim 1 or 2, wherein the low frequency information giving unit is a switching unit which switches a high frequency at a predetermined low frequency. .