JPS6026279B2 - Fluorescent light dimmer device - Google Patents

Description

[Detailed description of the invention] This invention relates to a crab lamp dimming device.

Figure 1 is a circuit diagram of a secondary example of a crab light dimmer device, in which a series circuit of a ballast 2 for dimming, a main ballast 3, and a fin light 4 is provided at both ends of a power source 1. A dimmer switch 5 is connected in parallel with the ballast 2, and a glow lamp 6 is connected between both filament non-power side terminals of the crab light lamp 4.

In this circuit, when the dimmer switch 5 is closed, both ends of the dimmer ballast 2 are shorted, and only the main ballast 3 is connected to the circuit, and the crab light 4 is connected only to the king ballast 3. When the dimmer switch 5 is opened, the dimmer ballast 2 is connected in series with the main ballast 3, and the crab light 4 is reduced in brightness by the impedance of the series circuit. The light turns on.

In this way, when the dimming ballast 2 is followed in series with the main ballast 3, dimming lighting of the honeylight lamp can be obtained, and when short-circuited, rated lighting can be obtained, but in the case of dimming lighting, the circuit impedance Since the temperature is high, the child heat current supplied to the filament of the crab light lamp 4 through the glow lamp 6 at the time of starting the pot light lamp 4 becomes small, which has the drawback that starting is difficult due to insufficient ripening.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to eliminate this drawback and provide an arrangement that provides sufficient preheating even when starting a crab light lamp in a dimmed state.

FIG. 2 shows an embodiment of the present invention, in which, in place of the dimming ballast 2 shown in FIG. A tube current phase control circuit 13 including a triac 7, a trigger auxiliary triac 8, a trigger diac 9, an oscillation capacitor 10, a charging resistor 11, and a current limiting resistor 12 is used to provide wide power synchronization to the triac 7. A trigger current lc is given.

That is, in this embodiment, the trigger current IG is a tube current 14 whose phase is delayed by approximately 45 degrees from the power supply voltage V, with the series circuit of the crab light lamp 4 and the main ballast 3 as a load as shown in FIG. and the delayed phase t of the preheating current 16, which is loaded with the main ballast 3 and the filament and whose phase lags by nearly 9 points with respect to the power supply voltage V, from 0 to the phase of the child heating current 16. It is assumed that the current has a wide range up to the phase plateau. In such a circuit, when the dimmer switch 5 is open, the current voltage V, synchronizes with the power supply voltage V,
In each half cycle of
When the current IG is applied to the triac 7, its phase a
The crab light lamp 4 is made conductive through the tube electric mirror 84, maintaining its conductive state beyond the half cycle of the power supply voltage V and until the phase of the next half cycle, and controlling the phase of the tube current L. For example, the brightness is reduced to about 60%.

When starting the crab light lamp 4 in a dimmed state, the trigger fin current lc is continuously applied to the triax 7 from phase 8, which is ahead of the preheating current phase, to phase t. Therefore, the triac 7 is fully conductive, and the child thermoelectric firewood a6 is applied at exactly the same time as the rated time without phase control, and the crab light lamp 4 is sufficiently preheated. As described above, the crab lamp dimmer device of the present invention performs tube current control by phase control of the thyristor, and the trigger current is set from a predetermined phase that is later than the phase of the tube current and ahead of the phase of the mature current. Since the tube current continues to flow over a predetermined period that includes the phase of the hot current, the phase of the tube current is controlled and the desired dimming is performed, and the hot current is sufficiently given without being phase controlled, and the desired dimming is performed. This has the effect of improving starting in a dimmed state while maintaining the dimmed state of the period.

In the embodiment, a glow lamp is used as an example of the starting element, but the starting element is not limited to a glow lamp, and may be any element that is connected between the non-power supply side terminals of the filament of the crab light lamp.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional example of a crab light dimming device, FIG. 2 is a circuit diagram showing an embodiment according to the present invention, and FIG. 3 is a waveform characteristic diagram in the above embodiment. 1... AC power supply, 2... Ballast for dimming, 3
...Main ballast, 4...Crab light, 5...
...Dimmer switch, 6...Glow lamp, 7...Triack, 13...Phase control circuit. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1 Connect a series circuit of a dimming thyristor, a main ballast, and a fluorescent lamp to both ends of the AC power supply, connect a fluorescent lamp starting element between the non-power supply side terminals of both filaments of the fluorescent lamp, and A power supply for the light thyristor that continues for a predetermined period including the phase of the preheating current from a predetermined phase that lags behind the phase of the fluorescent lamp tube current and precedes the phase of the preheating current flowing through the fluorescent lamp filament and the starting element. A fluorescent lamp dimmer characterized in that a synchronous trigger current is applied.