JPS6254202B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lighting fixture equipped with a dimmer.
FIG. 1 shows an example of a lighting fixture to which the present invention is applied. In the figure, 1 is the lighting equipment body, 2
3 is a reflector attached to the lower surface of the main body 1, 3 is a shade attached to the reflector 1, and 4 and 5 are circular fluorescent lamps, which are arranged concentrically in the horizontal direction with steps. The lamp 4 has a larger rated power and larger external dimensions than the lamp 5, and therefore has a larger total luminous flux.The lamp 4 is arranged concentrically close to the reflector plate 2. 6 and 7 are ballasts for lighting the lamps 4 and 5, respectively; 8 is a switch for switching and blinking the lamps 4 and 5; these lighting devices as a whole are connected by a hanging cord 1a fixed to the main body 1; Usually suspended from the ceiling.

FIG. 2 is a diagram showing the configuration of a conventional lighting circuit for the lighting fixture shown in FIG. 1. In FIG. 2, the ballast 6 and the lamp 4 are connected in series, the other end of the ballast 6 is connected to the contact 8a of the switch 8, and the other end of the lamp 4 is connected to one end of the power source 9. . A glow lamp 4a is connected in parallel to the lamp 4 via a filament. On the other hand, stabilizer 7
is connected in series with the lamp 5, the other end of the ballast 7 is connected to the contact 8a of the switch 8, and the other end of the lamp 5 is connected to one end of the power source 9 together with one end of the lamp 4. A glow lamp 5a is connected in parallel to the lamp 5 via a filament. The other end of the power source 9 is connected to the contact piece 8d of the switch 8.

Next, detailed operation will be explained. switch 8
When the contact piece 8d is connected to the contact point 8a by the operation of
Glow lamp 4 applied to each series circuit of lamps 5 and connected in parallel to lamps 4 and 5
The lamps 4 and 5 are fully lit by the operations of a and 5a. In this case, the illuminance directly below the lighting equipment is 5 lamps.
makes a larger contribution. Next, when the switch 8 is operated and the contact piece 8d is connected to the contact point 8b, the power supply 9 is applied only to the series circuit of the lamp 5 and the ballast 7, and only the lamp 5 is lit, and the lamp 5 generates the same luminous flux as above. do. Further, when the contact piece 8d is connected to the contact point 8c, both the lamps 4 and 5 are turned off. Therefore, this lighting fixture can be switched to 2 by operating switch 8.
Lights on → 1 light on → lights off. If only one lamp is turned on and used by operating the switch 8, the lamp 5 placed at the bottom of the lighting equipment is lit, so the illuminated surface directly under the lighting equipment (hereinafter referred to as the work surface) is Although the illuminance was lower than when the two lamps 4 and 5 were turned on, the luminous flux of lamp 5 effectively acted on the work surface, and the illuminance of the work surface could be made relatively high. However, since the lamp 4 is off, the light from the lighting fixture to the sides and above is extremely reduced, causing the walls and ceiling to become dark, making the entire room feel dark.
In addition, there was a large difference in illuminance between the work surface and other walls and ceiling surfaces, which was not a good visual environment.

On the other hand, there has been a lighting device as shown in FIG. 3 in the past.

In FIG. 3, like the conventional device shown in FIG. 2, 4 and 5 are circular fluorescent lamps, 6 and 7 are ballasts, and the lamp 4 and ballast 6, and the lamp 5 and ballast 7 are connected in series. One ends of the lamps 4 and 5 are connected to a power source 9, and one ends of the ballasts 6 and 7 are connected to a contact 8a of a switch 8. Further, glow lamps 4a and 5a are connected to the lamps 4 and 5 in parallel via filaments, respectively. 10 is a dimmer. The bidirectional thyristor 10a has contacts 8a, 8
b, and its gate is connected to one end of the power supply 9 via a series circuit of a bidirectional trigger thyristor 10b and a resistor 10d. A series circuit of a capacitor 10f and a variable resistor 10e is connected between the contact 8b and the anode of the bidirectional trigger thyristor 10b.
e connection point and trigger bidirectional thyristor 10b
A trigger element 10c is connected between the gates of the trigger element 10c. On the other hand, the other end of the power source 9 is connected to the contact piece 8d of the switch 8.

In the device configured as described above, when the contact piece 8d is connected to the contact point 8a by operating the switch 8, the power source 9 is applied to the series circuit of the lamp 4, the ballast 6, the lamp 5, and the ballast 7, and the lamp 4 and 5 are fully lit to generate a predetermined luminous flux. One side contact piece 8
When d is connected to the contact 8b, the power source 9 is connected to the dimmer 1.
A voltage as shown in FIG. 4 is applied to the series circuits of the ballasts 6 and 7 and the lamps 4 and 5, with the phase controlled at 0, and the lamps 4 and 5 are dimmed and turned on. That is, a trigger circuit consisting of a capacitor 10f, a variable resistor 10e, and a trigger element 10c generates a trigger pulse at a phase θ ₁ in FIG. 4 in the same manner as a well-known phase control circuit. This trigger pulse causes the bidirectional trigger thyristor 10b to conduct at phase _θ1 , supplying a gate current to the gate of the bidirectional thyristor 10a via the resistor 10d. Therefore, the bidirectional thyristor 10a conducts at phase θ ₁ in FIG.
Continuation is continued until phase θ ₀ , and the voltage shown in FIG. 4 is applied to each series circuit of ballasts 6, 7 and lamps 4, 5, and lamps 4 and 5 are dimmed and lit.
This phase θ ₁ can be changed by the variable resistor 10e, and thereby the luminous flux of the lamps 4 and 5 is also changed.

In the conventional device shown in Fig. 2, if the phase θ ₁ in Fig. 4 is set so that when lamp 51 is on, the illuminance of the work surface directly under the lighting equipment is the same, then lamps 4 and 5 are Since the luminous flux decreases at the same rate as when the light is turned on, the lamp 5 causes the wall surface,
The ceiling surface is also illuminated, reducing the illuminance uniformly throughout the room. Therefore, although the visual environment is good, there is a drawback that the power consumption is greater than when all 51 lamps are turned on.

It is an object of the present invention to provide a light control device that eliminates the above-mentioned drawbacks, reduces power consumption, and provides a good visual environment.

The details of this invention will be explained below with reference to Examples. FIG. 5 is a circuit diagram showing an embodiment of the present invention, and FIG. 6 is an explanatory diagram of the operation of the present invention. When explaining the configuration in FIG. 5, the same or corresponding parts as those in FIG. 3 will be given the same reference numerals, and the explanation thereof will be omitted, and the parts different from those in FIG. 3 will be mainly described. As is clear from a comparison between FIG. 3 and FIG. 5, dimmers 11 and 12, which are dimmer means having the same configuration as the dimmer 10 in FIG. 3, are provided separately for the lamps 4 and 5, The voltage of the power source 9 is input to the dimmer 12, and the output voltage of the dimmer 12 is input to the dimmer 11. In other words, contact 8 of switch 8
The input end of the dimmer 12 is connected to b2, and the output end of the dimmer 12 is connected to the series circuit of the ballast 7 and the lamp 5, and the input end of the dimmer 11 is connected to it. .

Further, a series circuit of the ballast 6 and the lamp 4 and a series circuit of the ballast 7 and the lamp 5 are connected to the contacts 8a ₁ and 8a ₂ of the switch 8, respectively.

In the device configured as described above, when the contact piece 8d of the switch 8 is connected to the contacts 8a1 and 8a2, the power source 9 is applied to the series circuit of the lamp 4 and the ballast 6 and the lamp 5 and the ballast 7. Similar to the conventional example shown in FIG. 3, the lamps 4 and 5 are fully lit. Also, by operating the switch 8, the contact pieces 8d are changed to 8b1, 8b.
2, the dimmer 1 is connected to the dimmer 1 through the contact 8b2.
A power source 9 is applied to 2. The dimmer 12 operates in the same manner as the conventional example shown in FIG.
2a conducts from the phase θ ₂ to θ ₀ shown in FIG. 6A, and the voltage shown in FIG. On the other hand, the output voltage of the dimmer 12, shown in FIG. 6A, is applied to the dimmer 11, and the dimmer 11 operates in the same manner as the dimmer 12, as shown in FIG. A voltage is applied to the lamp 4 during phases θ ₃ to θ ₀ . This voltage causes the lamp 4 to be dimmed and turned on. At this time, since the dimmer 11 controls the phase of the output voltage of the dimmer 12, the conduction start phase θ ₃ of the dimmer 11 always lags the conduction start phase θ ₂ of the dimmer 12. Therefore, the output voltage of the dimmer 12 is higher than the output voltage of the dimmer 11, and the dimming rate of the lamp 5 is always smaller than the dimming rate of the lamp 4. Here, the light attenuation rate is the light attenuation value (lm)/total luminous flux (lm). The output voltage of the dimmer 12 is set so that the luminous flux of the lamp 5 is close to full lighting, and the output voltage of the dimmer 11 is adjusted to
By reducing the luminous flux of
If it is set to be equal to the conventional example shown in the figure, the light attenuation rate of lamp 5, which greatly contributes to the direct illuminance, will be small, and the light attenuation rate of lamp 4, which does not contribute much, will be considerably large.
The total power consumption of lamps 4 and 5 is lower than that of the conventional example shown in Figure 3, and since lamp 4 is also dimmed, the illuminance on the walls and ceiling is lower than that of the conventional example shown in Figure 2. The height allows for a relatively good viewing environment. Lamp 4 and lamp 5 like this
By making a difference in the light attenuation rate, it is possible to obtain the same illuminance on the work surface as before with less power consumption, and also to increase the illuminance on the walls and ceiling, creating a relatively good viewing environment.

In the above explanation, the dimmers 11 and 12 use phase control, and the ballasts 6 and 7 use chiyoke coils.
The ballast is not limited to these, and may be one that changes the impedance of the ballast, a high frequency lighting using an inverter, or the like.

Furthermore, although the case where two lamps with different rated power and external dimensions are lit in the same lighting fixture has been described, the present invention is not limited to this, and the same effect can be obtained even if three or more lamps are arranged substantially concentrically and lit. In addition, the lamps may be arranged in such a way that lamps with different external dimensions are arranged in concentric circles within the same plane, and even lamps with the same external dimensions can be arranged above and below in substantially concentric circles to obtain the same effect. Of course.

As described above, according to the present invention, when controlling the dimming of a plurality of circular fluorescent lamps arranged concentrically within the same lighting fixture, the dimming rate of the lamp that contributes the most to the illuminance directly below the lighting fixture is By setting the dimming rate lower than that of the lamp, the illuminance of the work surface can be set high with less power consumption, and the wall and ceiling surfaces can also be illuminated, creating a good viewing environment. be.

[Brief explanation of the drawing]

Figure 1 is an outline drawing of a lighting fixture to which this invention is applied, Figures 2 and 3 are circuit diagrams showing the configuration of a conventional device, Figure 4 is an explanatory diagram of Figure 3, and Figure 5 is an illustration of the invention. FIG. 6 is a circuit diagram showing the configuration of an embodiment of the device according to the present invention, and FIG. 6 is a moving object explanatory diagram thereof. In the figure, 1 is the lighting equipment body, 4 and 5 are circular fluorescent lamps, 6 and 7 are ballasts, 8 is a switch, 1
1 and 12 are dimming means. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. In a dimmable device in which a plurality of circular fluorescent lamps are arranged concentrically, the dimming rate of the circular fluorescent lamp that contributes most to the illuminance directly below it is determined by the dimming rate of the other circular fluorescent lamps. A lighting fixture characterized by being provided with a dimming means that makes the light intensity smaller than the light intensity. 2 Among a plurality of circular fluorescent lamps arranged concentrically, the circular fluorescent lamp having a larger total luminous flux than the lower circular fluorescent lamp and contributing less to the direct illuminance than the circular fluorescent lamp above is arranged on the upper side. A lighting fixture according to claim 1, characterized in that: