JPS603848A - High-pressure sodium lamp with built-in ballast - Google Patents

Abstract

PURPOSE:To reduce the restriking voltage and improve the lamp efficiency by increasing the luminous tube diameter within a specific range. CONSTITUTION:In a high-pressure sodium lamp having a built-in ballast and provided with a luminous tube 2 made of a translucent ceramic tube and a resistor 3 made of a tungsten filament connected in series with the luminous tube 2 in an outer tube 1 kept at high vacuum, high efficiency and stable lighting throughout the life time can be obtained by simultaneously satisfying two equations 0.0057Wl+4.53<=D<=0.0067Wl+6.27, 0.02Wl+100<=Vb, where D is the luminous tube diameter, Vb is the luminous tube voltage, and Wl is the lamp voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION In the present invention, an arc tube made of translucent ceramic and filled with sodium, mercury, and xenon gas is connected in series to the arc tube in the outer bulb of the lamp. This invention relates to a new high-pressure sodium lamp with a built-in ballast that has a built-in resistor.

High-pressure sodium has recently begun to be widely used due to its high efficiency and long life.However, in order to light this lamp, an external ballast is required, which makes it difficult to install an external ballast at shops and temporary construction sites. etc., it was inappropriate. Therefore, similar to the conventional high-pressure mercury lamps with built-in ballasts, high-pressure sodium lamps also have a resistor made of tungsten filament placed inside the lamp's outer bulb and connected in series with the arc tube to achieve high efficiency and long life. It is desired to realize a high-pressure sodium lamp with a built-in ballast that takes advantage of this.

Compared to mercury lamps and metal halide lamps, high-pressure sodium lamps have a higher re-ignition voltage than mercury lamps or metal halide lamps, even when lit with a choke-type (slow-phase) external ballast, and are more likely to go out. For this reason, the rated arc tube voltage during lighting is 130V for mercury lamps, while high-pressure sodium lamps are designed to be about 30V lower, about 100V, although this varies depending on the lamp size (watt). If a ballast consisting of a resistor is applied to such a high-pressure sodium lamp, the phase of the discharge sustaining voltage and the arc tube voltage will become exactly the same, so
It becomes easier to erase. If the arc tube voltage is further lowered to prevent this from going out, the voltage ratio consumed by the resistor will increase and the lamp efficiency will drop significantly, so high-pressure sodium lamps with a built-in ballast have not been put into practical use to date.

Therefore, we conducted an experiment focusing on the point that the restriking voltage was reduced by making the arc tube thicker in order to lower this restriking voltage and increase efficiency. When the tube voltage is Vb (volt) and the inner diameter of the arc tube made of a translucent ceramic tube is D (mm), 0.0057Wl+4.53≦D≦0.0067Wl+
It has been confirmed that this objective can be achieved when the following conditions are simultaneously satisfied: 6.270.02Wl+100≦Vb.

The present invention will be explained below based on Examples and experimental results.

Figure 1 shows the configuration of the high-pressure sodium lamp with a built-in ballast used in the experiment. Inside the outer bulb 1, which is maintained in a high vacuum, is an arc tube 2 made of a translucent ceramic tube; A resistor 3 consisting of tungsten filaments connected in series is provided. Further, a proximal conductor 4 is provided as a starting auxiliary external electrode close to the outer surface of the arc tube 2, and this proximal conductor 4 serves as a high-voltage pulse terminal of a high-voltage pulse generator 6 housed in the base 5. is connected to.

The arc tube 2 is filled with sodium, mercury, and xenon scum as a starting gas. When power is applied to the lamp, a high voltage pulse generated from the high voltage pulse generator 6 is applied to the adjacent conductor 4, and a pulse is generated inside the arc tube. The enclosed xenon gas is discharged to light the lamp, and the tungsten filament, which is the lamp's built-in ballast, brings the lamp into a stable lighting state.

As can be seen from Figure 2, which shows the relationship between the xenon gas filling pressure and the pulse voltage required for starting, in a lamp configured to start by applying a high voltage pulse to a nearby conductor, if the xenon gas filling pressure exceeds 100 meters, The pulse voltage required for starting increases, and as the lamp lighting time elapses, debris from the electrodes 7 and 7' provided at both ends of the arc tube or sodium and mercury adhere to the inner wall of the arc tube, reducing the effect of the nearby conductor. In order to ensure that the lamp can be started throughout its life, the xenon filling pressure in the arc tube should be 100 meters or less, preferably about 50 Torr, since this increases the pulse voltage required for starting.

Next, the experimental results of a 400-watt high-pressure sodium lamp with built-in ballast will be explained. Table 1 shows the specifications of the arc tube used in the test.

Incidentally, the tube wall load is the value when the arc tube power Wb is 200 W, but from the viewpoint of lifespan and efficiency, it is made approximately equal to the tube wall load of the arc tube of a normal high-pressure sodium lamp. The xenon gas inside the arc tube is 50 Torr and for each arc tube diameter D,
Sodium and mercury are sealed in order to obtain the highest arc tube efficiency lm/Wb and a predetermined arc tube voltage Vb. Table 2 shows the results of measuring the initial characteristics when the power source voltage was 200 V and the lamp power Wl was 400 W using these arc tubes and variable resistors.

Here, the light emission voltage Vb is the upper limit value at which discharge can be maintained when the power supply voltage is 180 V, taking into account fluctuations in the power supply voltage during actual use, and other characteristics are naturally determined by this upper limit value of the light emission tube voltage Vb.

As can be seen from Table 2, the arc tube efficiency lm/Wb reaches its maximum value when the arc tube diameter D is 7 mm, but when the arc tube diameter D becomes thicker, the vapor pressure of mercury in the open tube increases, causing an increase in mercury luminescence. The arc tube efficiency lm/Wb decreases as the effective luminous length becomes shorter, but the arc tube power increases by increasing the upper limit of the arc tube voltage Vb, so the lamp efficiency lm/Wl is determined by the arc tube diameter D. shows the highest value at 8 mm. Figure 3 shows the arc tube diameter D and lamp efficiency lm/W in Table 2.
From a practical standpoint, when the arc tube diameter D is 8 mm, it is at least 90% of the maximum value of 50 lm/Wl, that is, 45 lm.
/Wl, the arc tube diameter should be 6.5 to 9.2.
It can be said that it is sufficient if it is within the range of mm (shaded area). However, from Fig. 4, which shows the relationship between the arc tube diameter D and the arc tube voltage when the lamp efficiency lm/Wl becomes 45 or more when the lamp power Wl is constant at 400 W, it is clear that the luminescence The range of tube voltage Vb is preferably 10V or more, and for that purpose, the arc tube diameter D should be 68 to 8.9 m.
It needs to be m.

Optimally, by setting the arc tube diameter D to 8 mm, the arc tube voltage Vb can range from 110 to 140V and 30V.

Next, the same experiment as with the 400 watt built-in ballast lamp was conducted on 700 watt and 1000 watt high-pressure sodium lamps with built-in ballast, and the results were as follows.

Figures 5 and 6 show the results.
As shown in the figure, at 700 watts, the arc tube diameter D is about 10 mm and the maximum lamp efficiency lm/Wl is 55. At 1000 watts, the arc tube D is about 12 mm and the maximum lamp efficiency lm/Wl is 60. As with 400 watts, the lamp efficiency lm/Wl is 90% or more of the maximum lamp efficiency, and from FIG. 6, the arc tube diameter D at which the arc tube voltage Vb range is 10 V or more is 8.5 to 11.0 mm for 700 watts. , 10. at 1000 watts.
It will be 2 to 12.9 mm.

In that case, the lower limit of the arc tube voltage Vb is 1 at 700 watts.
15V, 1000 watts becomes 122V.

Figures 7 and 8 summarize the above results. Figure 7, which shows the lamp power Wl and the arc tube diameter D, shows that the lamp efficiency lm/Wl is more than 90% of the maximum lamp efficiency, and In order to set the arc tube voltage Vb in the range of 10 V or more, the arc tube diameter must be within the shaded range, and from FIG. 8, the arc tube voltage Vb must also be at least within the shaded range. That is, the arc tube diameter and arc tube voltage Vb are 0.0057Wl+4.53≦D≦0.0067W for the lamp power Wl.
It is necessary to simultaneously satisfy two equations: l+6.270.02Wl+100≦Vb.

According to the present invention, by satisfying the above formula,
It has become possible to obtain a high-pressure sodium lamp with a built-in ballast that is highly efficient and stably lit throughout its life.

[Brief explanation of drawings]

Figure 1 is a schematic configuration diagram of a high-pressure sodium lamp with a built-in lamp according to the present invention, and Figures 2 to 8 are characteristic diagrams adopted to explain the present invention based on experimental results.
The figure is a diagram showing the relationship between the filling pressure of xenon gas and the pulse voltage required for starting, Figures 3 and 4 are diagrams showing the relationship between the arc tube diameter, lamp efficiency, and arc tube voltage in a 400 watt lamp, Figures 5 and 6 show 700 watts and 100 watts.
A diagram showing the relationship between the arc tube diameter, lamp efficiency, and arc tube voltage in a 0 watt lamp, Figure 7 is a diagram showing the relationship between the lamp power and the arc tube diameter, and Figure 8 is a diagram showing the relationship between the lamp power and the arc tube voltage. FIG. 1... Outer tube, 2... Luminescent tube, 3...
・Resistor. 6...Pulse generator, 4...Proximity conductor. -Kl Eye direction 7 Eye 2, concave
] Fig. 5 Pivot control F)
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Claims (1)

[Scope of Claims] (1) Inside the lamp's outer bulb, there is an arc tube made of a translucent ceramic tube and filled with sodium, mercury, and xenon gas as a starting gas; In a high-pressure sodium lamp with a built-in ballast connected to a resistor, the lamp power is Wl (W) and the arc tube voltage is Vb (V
), when the inner diameter of the arc tube is D (mm), 0.0057Wl+4.58≦D≦0.067Wl+6
．． A high-pressure sodium lamp with a built-in ballast, characterized in that it simultaneously satisfies the following conditions: 270.02Wl+100≦Vb. (2) A stable lamp with a built-in arc tube made of a translucent ceramic tube and filled with sodium mercury and xenon gas as a starting gas, and a resistor connected in series to this arc tube, inside the outer bulb of the lamp. In a built-in high pressure sodium lamp, the lamp power is Wl (W) and the arc tube voltage is Vb.
(v), when the inner diameter of the arc tube is D (mm), 0.0057Wl+4.53≦D≦0.0067Wl+
6.270.02 The conditions of Wl+100≦Vb are simultaneously satisfied, the keysenon gas filling pressure is set to 100 torr or more, and the lamp is started by applying a high voltage pulse to a conductor provided close to the exterior surface of the arc tube. High-pressure sodium lamp with built-in ballast.