JP2006134845A - Stepwise light-dimming stabilizer for discharge lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the loss of a step-up transformer 2 in total lighting. <P>SOLUTION: The step-up transformer 2 and a dimming impedance component 3 are arranged between an impedance component 1 in total lighting and a discharge lamp 4, and a current in the total lighting of the discharge lamp 4 is allowed to flow by bypassing a step-up part of the step-up transformer 2 and the dimming impedance component 3 in total lighting. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a ballast for a discharge lamp having a function of step dimming in a ballast for lighting a discharge lamp with an AC power supply.

  FIG. 4 shows a normal dimming ballast for a discharge lamp having a function of step dimming. The step-up transformer 2 is for increasing the secondary voltage in order to prevent the discharge lamp from extinguishing at the time of dimming. The all-light impedance 1 and the dimming impedance 3 are connected in series, and the switch 5 at all times. Is closed, the output of the discharge lamp 4 is all light, and at the time of dimming, the switch 5 is opened and the impedance is increased to reduce the output of the discharge lamp for dimming. Reference numeral 6 denotes an AC power source.

  In the above circuit, since the all-light current of the discharge lamp 4 flows through the step-up transformer 2a of the step-up transformer 2 in all light, and the step-up transformer 2 is always excited by the voltage of the AC power source 6, the step in all light is performed. The loss of the up transformer 2 is large.

  An object of the present invention is to reduce the loss of the step-up transformer 2 during all light.

  In the present invention, the step-up transformer and the dimming impedance are arranged between the all-light impedance and the discharge lamp. Allow the light current to flow.

In the present invention, the step-up transformer and the dimming impedance are arranged between the all-light impedance and the discharge lamp, and the all-light of the discharge lamp is bypassed by bypassing the boosting portion of the step-up transformer and the dimming impedance during all light. The main characteristic is that the hour current flows.
According to this, it is possible to reduce the loss of the step-up transformer during all light.

An embodiment of the present invention will be described with reference to FIG.
The discharge lamp stage dimming ballast according to the present invention of FIG. 1 has a step-up transformer 2 connected to the output side of the all-light impedance 1 and a dimming impedance 3 connected to the output side of the boosting portion 2a. A discharge lamp 4 is connected to the output side, and a switch 5 is connected between the boosting portion 2 a and the dimming impedance 3.
In this circuit, at the time of dimming, the secondary voltage is increased by the step-up transformer 2 by opening the switch 5 and the output of the discharge lamp 4 is reduced by the dimming impedance 3 to be dimmed. Further, by closing the switch 5 during all light, the current during all light of the discharge lamp 4 flows, bypassing the step-up transformer 2a of the step-up transformer 2 and the dimming impedance 3.

As a result, the all-light current of the discharge lamp 4 does not flow through the step-up transformer 2a of the step-up transformer 2 during all light, and the step-up transformer 2 is equivalent to the voltage drop of the all-light impedance 1 from the voltage of the AC power source 6. Since it is excited at a voltage as low as possible, the loss of the step-up transformer 2 can be reduced.
The switch 5 is a switch such as an operation switch built in the ballast or a relay that is activated by an external operation.

Another embodiment of the present invention will be described with reference to FIG. The discharge lamp stage dimming ballast according to the present invention shown in FIG. 2 has dimming impedances 7 and 8 provided in parallel, and the dimming impedance 8 is connected to a switch 9 in series.
In this circuit, when the switch 5 is opened, the dimming state is entered. Further, the dimming state is different between the dimming state where the switch 9 is closed and the dimming state where the switch 9 is opened.
The other configurations and functions are the same as those of the first embodiment.

Still another embodiment of the present invention will be described with reference to FIG. The discharge lamp stage dimming ballast according to the present invention in FIG. 3 has a timer 10 built in the ballast, the timer 10 is powered by an AC power source 6, and the timer 10 opens the switch 5 after a predetermined time has elapsed. In this way, the light is adjusted.
It is also possible to add a switch to the power supply side of the timer and the ballast and open the power supply for the part related to lighting of the discharge lamp after a predetermined time. Needless to say, the power source of the timer can be a power source different from that of the ballast. Other configurations and functions are the same as those of the first embodiment.

  Circuit diagram of the present invention   Other circuit diagrams related to the present invention   Other circuit diagrams related to the present invention   Conventional circuit diagram

Explanation of symbols

1: Impedance at all light 2: Step-up transformers 3, 7, 8: Dimming impedance 4: Discharge lamps 5, 9: Switch 10: Timer

Claims (3)

  The step-up transformer and the dimming impedance are arranged between the all-light impedance and the discharge lamp, and the all-light current of the discharge lamp flows by bypassing the step-up transformer's boosting part and the dimming impedance during all light. A step dimming ballast for a discharge lamp characterized by the above.   2. The stage dimming ballast for a discharge lamp according to claim 1, wherein a plurality of dimming impedances are provided, and the dimming levels are set to a plurality of levels by switching or changing the dimming impedances. .   2. The discharge lamp stage dimming ballast according to claim 1, wherein switching between the all-light state and the dimming state is performed by a timer built in the ballast.

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