JPH1012393A - Infrared remote control luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infrared remote control luminaire in which the flickering of a discharge lamp is prevented by providing a booster type chopper circuit driven by the output of a rectifier and having a smoothing capacitor on the output side on the upstream side of an inverter circuit. SOLUTION: A commercial ac power source 21 is rectified by a rectifier 22, and made to a substantially constant voltage by a booster type chopper circuit 24 having a smoothing capacitor 23 on the output side. An inverter circuit 26 is driven by the substantially constant voltage output to convert the output into a high frequency having substantially fixed frequency, and this high frequency output is supplied to a discharge lamp 25 to light it. Thus, an infrared remote control luminaire in which the power factor can be extremely improved, a power source harmonic wave leaked to the commercial ac power source 21 side can be reduced, and the lamp current of the discharge lamp 25 can be made substantially constant regardless of the voltage fluctuation of the commercial ac power source 21 can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared remote control lighting device.

[0002]

2. Description of the Related Art As shown in FIG. 2, a conventional infrared remote control illuminator includes a rectifier 2 and a smoothing capacitor 3 for rectifying a commercial AC power supply 1, and an output of the smoothing capacitor 3 is converted into a high frequency to discharge a lamp ( An inverter circuit 5 for supplying a lamp 4), a light receiving section (infrared light receiving module) 8 for receiving an infrared remote control signal 7 from an infrared remote control transmitter 6, and an output of the light receiving section 8 via the inverter circuit 5 A control means 9 including a microcomputer for controlling the lighting state of the discharge lamp 4 and a feedforward circuit 10 for detecting a voltage change of the smoothing capacitor 3 and changing a high frequency output frequency of the inverter circuit 5 are preferable. Used. The outputs of the feedforward circuit 10 and the control means 9 are applied to the inverter circuit 5 via an inverter control circuit 11 serving as an interface. To describe the operation of this conventional example, when the voltage of the commercial AC power supply 1 decreases, the voltage of the smoothing capacitor 3 also decreases, and the feedforward circuit 10 acts to lower the high frequency output frequency of the inverter circuit 5. As a result, the inductance value of an inductor (not shown) connected in series between the output of the inverter circuit 5 and the discharge lamp 4 decreases, and the lamp current of the discharge lamp 4 becomes substantially constant even when the voltage of the commercial AC power supply 1 decreases. Acts to keep. Also, even if the voltage of the commercial AC power supply 1 increases, the discharge lamp 4
In order to keep the lamp current substantially constant. In addition, although a ripple component based on the frequency of the commercial AC power supply 1 considerably remains in the output voltage of the smoothing capacitor 3, the feedforward circuit 10 also causes the high frequency output frequency of the inverter circuit 5 to fluctuate due to the ripple fluctuation. Acting to keep the lamp current of the discharge lamp 4 substantially constant,
The flicker can be prevented.

[0003]

However, as a result, the high-frequency output frequency component of the inverter circuit 5 is reduced as shown in FIG.
, The frequency component contained in the light of the discharge lamp 4 approaches the subcarrier frequency fr (about 36.7 kHz) of the infrared remote control signal 7 and interferes as the optical noise 12. That is, when the optical noise 12 enters the light receiving unit 8, the infrared remote control signal 7 is masked, and the control by the infrared remote control signal 7 becomes ineffective. 3, the voltage of the commercial AC power supply 1 is 11
In the case of 0V, although there is no particular problem,
Are 100 V and 90 V, the frequency component of the optical noise 12 that interferes with the subcarrier frequency fr of the infrared remote control signal 7 increases, and the maximum reach of the infrared remote control signal 7 decreases. Note that the thick line in FIG. 3 indicates the bandpass characteristic of the light receiving unit 8 by frequency versus gain, and the dotted line indicates the high frequency output component of the inverter circuit 5 by frequency versus lamp current. In general, the high frequency output center frequency of the inverter circuit 5 is the subcarrier frequency fr (about 36.
7 kHz) and a higher frequency (for example, about 60 kHz).
z), the higher the value, the more excessively the components of the inverter circuit 5 generate heat, so that it is necessary to use a component with a high rating, or the higher harmonic component of the high-frequency output of the inverter circuit 5 is reduced. Radio noise increases due to high levels in the mid-wave radio frequency range. Therefore, it is advantageous to set the high-frequency output center frequency of the inverter circuit 5 as low as possible. However, in the conventional example of FIG. In view of the problems to be solved, an object of the present invention is to provide an infrared remote control lighting device that can prevent flickering of a discharge lamp and can significantly improve the maximum reach of an infrared remote control signal. Other objects of the present invention will become apparent from the following description.

[0004]

SUMMARY OF THE INVENTION To summarize the present invention, a rectifier for rectifying a commercial AC power supply, a chopper circuit driven by the output of the rectifier and having a smoothing capacitor on the output side, and a substantially constant voltage output of the chopper circuit An inverter circuit that supplies a high-frequency output, which is converted to a substantially constant frequency by being driven by the discharge lamp, to the discharge lamp, a light receiving unit that receives an infrared remote control signal with a subcarrier frequency substantially different from the substantially constant frequency, Control means for controlling the lighting state of the discharge lamp via the inverter circuit in accordance with the output of the light receiving unit.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described. However, these are merely exemplary embodiments adopted based on the present invention, and the present invention is limited to matters unique to only the embodiments. The technical scope of the present invention must be determined based on the matters stated in the claims or matters that are substantially equivalent thereto.

[0006] The embodiment shown in FIG.
Rectifier 22, a booster chopper circuit 24 driven by the output of the rectifier 22 and having a smoothing capacitor 23 on the output side, and a substantially constant frequency by being driven by the substantially constant voltage output of the chopper circuit 24. an inverter circuit 26 for supplying a high-frequency output converted to fo to a discharge lamp (lamp) 25; and an infrared remote control signal 2 having a subcarrier frequency fr substantially different from the substantially constant frequency fo.
7, a light receiving unit (infrared light receiving module) 28 for receiving
This is an infrared remote control lighting device including control means 29 including a microcomputer for controlling the lighting state of the discharge lamp 25 through the inverter circuit 26 based on the output of the light receiving unit 28. The output of the control means 29 is applied to the inverter circuit 26 via an inverter control circuit 30 serving as an interface as appropriate. Reference numeral 31 denotes an infrared remote control transmitter. Further, the high-frequency output of the inverter circuit 26 is preferably supplied to the plurality of discharge lamps 25, 25 collectively. Furthermore, the subcarrier frequency f of the infrared remote control signal 27
When r is about 36.7 kHz, the inverter circuit 26
Is preferably a substantially constant frequency in the range of about 45 to 55 kHz.

According to the present embodiment, the chopper circuit 24
Is provided, the power factor is extremely improved, and power supply harmonics leaking to the commercial AC power supply 21 side can be extremely reduced. Also, a suitably designed chopper circuit 24 typically has 3
Since the high-frequency operation of chopping the output of the rectifier 22 at a high frequency of about 0 kHz is performed, the output of the chopper circuit 24 includes almost no ripple component based on the frequency of the commercial AC power supply 21 by the relatively low-capacity smoothing capacitor 23. Since a constant voltage is obtained and the inverter circuit 26 is driven by the substantially constant voltage output, flickering of the discharge lamp 25 can be prevented, and the lamp current of the discharge lamp 25 is substantially constant regardless of the voltage fluctuation of the commercial AC power supply 21. In particular, when the voltage of the commercial AC power supply 21 rises, excessive heat generation of the components constituting the inverter circuit 26 can be prevented, and it is not necessary to employ a component having a high rating for the components. Furthermore, the inverter circuit 26 has a high-frequency output that is converted to a substantially constant frequency fo (for example, about 52 kHz) by being driven by the substantially constant voltage output of the chopper circuit 24. There is substantially no dispersion distribution of such high frequency components, and frequency components included in the light of the discharge lamp 25 can be prevented from approaching the subcarrier frequency fr (about 36.7 kHz) of the infrared remote control signal 27,
The two can be easily distinguished from each other by the bandpass characteristic of the light receiving unit 28, and a noise signal due to the optical noise 32 is not substantially output from the light receiving unit 28. Thus, the infrared remote control signal 2
Since 7 is not masked by the optical noise 32, the maximum reach of the infrared remote control signal 27 is greatly improved. Thus, the high frequency output frequency of the inverter circuit 26 can be set within a lower frequency range (approximately 45 to 55 kHz), the heat generation of the components of the inverter circuit 26 can be reduced, and it is not necessary to employ a component with a large rating. Then, the harmonic components of the high-frequency output of the inverter circuit 26 are less likely to interfere with the medium-frequency radio frequency range,
There is also an advantage that radio noise can be reduced, and extremely advantageous effects can be obtained in various points.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing an embodiment of the present invention.

FIG. 2 is a circuit block diagram according to a conventional example.

FIG. 3 is a frequency characteristic diagram comparing the present invention example and the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Commercial AC power supply 22 Rectifier 23 Smoothing capacitor 24 Chopper circuit 25 Discharge lamp (lamp) 26 Inverter circuit 27 Infrared remote control signal 28 Light receiving part (Infrared light receiving module) 29 Control means

Claims (3)

[Claims] 1. A rectifier for rectifying a commercial AC power supply, a chopper circuit driven by an output of the rectifier and having a smoothing capacitor on an output side, and driven by a substantially constant voltage output of the chopper circuit to obtain a substantially constant frequency. An inverter circuit for supplying the converted high-frequency output to the discharge lamp, a light receiving unit for receiving an infrared remote control signal with a subcarrier frequency substantially different from the substantially constant frequency, and an output of the light receiving unit via the inverter circuit. And a control unit for controlling a lighting state of the discharge lamp. 2. The infrared remote control lighting device according to claim 1, wherein a high-frequency output of the inverter circuit is supplied to a plurality of discharge lamps collectively. 3. The sub-carrier frequency of the infrared remote control signal according to claim 1, wherein the sub-carrier frequency of the infrared remote control signal is about 36.7 kHz.
An infrared remote control lighting device in which the high frequency output of the inverter circuit is substantially constant within a range of about 45 to 55 kHz.