JPS58218799A - Full light-dimming converting device in inverter for discharge lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for switching a discharge lamp load between full-light mode and dimming mode in a discharge lamp inverter.

Circuits that light discharge lamps at high frequency using an inverter are often used because they have good lighting efficiency and are easy to dim. It is necessary to provide a switch in the discharge lamp circuit, which is the secondary side of the inverter.

By the way, since the high voltage output of the inverter is applied to this switch, it is required to have a high withstand voltage, but it has the disadvantage that it is easily burnt out and is expensive.

The purpose of the present invention is to fundamentally eliminate the above-mentioned drawbacks, and in conjunction with the switch on the power supply side of the inverter,
When this switch is turned off, a full-light/dimmer changeover switch arranged in the discharge lamp circuit of the inverter is operated to prevent burnout of this switch.

Hereinafter, the present invention will be explained based on examples.

Fig. 1 is a circuit diagram of an inverter for a discharge lamp, where 1 is an AC power supply, 2 is an inverter, 3 is a discharge lamp, A is a first switch that disconnects the power supply circuit of the inverter 2, and B is a discharge lamp 30 of the inverter 2. A second switch 4 for switching between full light and dimming in the circuit is an inductor inserted in series in the circuit of the discharge lamp 3, and inserted or removed from the discharge lamp 3 by the second switch B. The inverter 2 has a high voltage output necessary to start the discharge lamp 3 on its output side, for example, a voltage of about eooV. FIGS. 2 and 3 show the first and second switches 4. This is a specific configuration of H, in which first and second cam devices 6 and 7 mounted on the shaft 5 are operated in conjunction with each other, and each cam device has a different width. In each cam device, each movable contact 8, 9 is configured to connect/disconnect with each fixed contact 10, 11. 1st
As shown in FIG. 3, the second switches A and B displace their respective movable contacts 8 and 9 as the shaft 5 is rotated. The movable contact 8 is pushed down by the device 6 and the first switch A
is turned off, and then the second switch B is arranged to be turned off. Finally, the first switch A returns to on, but the second switch B remains off.

Therefore, in the above operation, when the first switch A is off, the second switch B is turned off, and the discharge lamp 3 is turned on via the inductor 4, so that it is in a dimming state. However, in order to switch the discharge lamp 3 to the full light state, turn the first and second switches A in the process from right to left in the figure.
, B, and even during this switching, the first
Since the second switch B is turned on after the switch A is turned off, the second switch B is switched when the first switch A is off. Note that the first and second
Although the mechanism for operating the cam devices 6 and 7 has been omitted, a pull switch type or a type in which the cam devices are rotated by a knob may be used.

As is clear from the above embodiments, the present invention includes a first switch that connects and disconnects the power supply circuit of the inverter, and a second switch that switches between full light and dimming in the discharge lamp circuit of the inverter. Further, the second switch is configured such that each movable contact connects and disconnects with each fixed contact by first and second cam devices having different widths that operate in conjunction with each other, so that when the first switch is off, the first and second cam devices have different widths. This is a full-dimmer/dimmer switching device for a discharge lamp inverter, which is characterized by having two switches.The second switch is switched off while the high-voltage output of the inverter is not being applied, so there is no arc at this switch. Since it does not occur,
2. It becomes possible to prevent such burnout accidents,
It is possible to provide a highly reliable full-light/dimming switching device.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram according to an embodiment of the present invention, Fig. 2 is a perspective view of a cam device constituting the first and second switches, and Fig. 3 is an explanatory diagram of the operation of the first and second switches. It is. 1...-AC power supply, 2-...inverter, 3...
・Discharge lamp, 4... Inductor, 5... Axis, 6
...First cam device, 7 ...Second cam device, 8
, 9 ... movable contact, 10 , 11- - fixed contact,
A...-first switch, B...second switch. Name of agent: Patent attorney Toshio Nakao and one other person ζ Figure 2 Figure 3

Claims (1)

[Claims] It is equipped with a first switch that connects and disconnects the power supply circuit of the inverter, and a second switch that switches between full light and dimming in the discharge lamp circuit of the inverter, and the first and second switches have different widths that operate in conjunction with each other. A discharge lamp characterized in that each movable contact is configured to connect and disconnect with each fixed contact in the first and second cam devices, so that the second switch is switched when the first switch is turned off. Full-light - dimming switching device for inverters.