JPS58126659A - High pressure metal-vapor electric-discharge lamp - Google Patents

Abstract

PURPOSE:To give a pulse voltage which can securely perform starting of a lamp by connecting a non-linear capacitor parallel to an emission tube, and installing said capacitor either in an outer tube or in a base. CONSTITUTION:An emission tube 1 is installed in an outer tube 17. A non-linear capacitor 21 having a capacity of over 1,000PF and a saturation voltage of over 20V is connected parallel to the emission tube 1, and installed either in the outer tube 17 or in a base 18. As indicated in the figure, while a current flows in the capacitor 21 which is made of barium titanate or the like, the charge (Q) of the capacitor 21 increases as its voltage (V) increases. However, when the voltage (V) reaches a given value (Vs), the charge (Q) is saturated, and the current doesn't flow in the capacitor 21. Therefore, when the capacitor 21 is applied to a circuit indicated in the figure, a pulse voltage sufficiently high for the starting of a lamp is applied to the lamp since any current doesn't flow in the capacitor 21 when the voltage (V) of the capacitor 21 reaches the value (Vs).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to high-pressure mercury lamps in which mercury is sealed together with a rare gas in the arc tube, high-pressure sodium lamps in which mercury and metal halides are sealed, metal halide lamps in which mercury and metal halides are sealed, etc. This invention relates to improving the starting characteristics of high-pressure metal vapor discharge lamps.

The details of this invention will be explained below by taking a metal halide lamp as an example.

A metal halide lamp is a lamp that greatly improves the efficiency and color rendering properties of a high-pressure mercury lamp by enclosing a metal halide in its arc tube. However, Jinnoki's lamp had a drawback in that it had a high starting voltage due to the inability to use materials with a low work function such as barium oxide as the electron emitting material. This drawback has been overcome by using a Penning gas such as neon-argon as a rare gas, and a metal paralite lamp that can be lit with an inexpensive mercury lamp ballast has been put into practical use. Figure 1 shows an example of the configuration of this type of metal halide lamp, and Figure 2 shows its circuit configuration. An auxiliary electrode (3) is disposed in the vicinity of at least one of the main electrodes (2a) to face it.

The main electrode (2a) is connected to a current supply line (6a) through a molybdenum foil (4a), and connected to a stem lead (r4a) through a support frame (7a). The other main electrode (2b) is similarly connected to the stem lead (14b) via the molybdenum foil (41), the current supply line (6b), and the tungsten wire 0. On the other hand, the auxiliary electrode (3
) is connected to the stem lead (1
4b). 0 is an insulator for fixing metal. And 9 arc tubes (11 is the holding plate (8a)
(8b) *The support frame (7a) is fixed within the surface of the outer tube with the 8-cap by screws, etc. (c) is the vapor pressure of the metal(s) and halogenide(s) inside the arc tube (0). A heat-retaining film made of zirconium oxide provided to increase the temperature, (9)
is a zirconium-aluminum colored getter, αe
is the stem. In FIG. 2, 0 is a ballast for a high-pressure mercury lamp, and aI is a power source. Neon - inside the arc tube +11
An example of a case where argon gas is sealed as a rare gas together with a predetermined amount of mercury and a metal chloride, and the power output is 400W is t/C and Neo 7-1pycon (0.5%) 4
0 Torr is enclosed. Then, when Yomoto city pressure is applied through the ballast ■, a glow discharge occurs between the main electrode (2a) and the auxiliary electrode (3), and then the main electrode (2a
), (2b)! '&! Transition to the main discharge of j. usually,
Since a resistance of about IOKΩ to 40Ω is used as the starting resistance a, the glow discharge current is small, and as a result, the starting voltage is easily affected by the impure gas inside the arc tube (11), and the neon- It was difficult to increase the argon sealing pressure.

Therefore, during its life, the electrodes wear out significantly during startup, and the luminous flux maintenance rate is low.Furthermore, in order to prevent impurity gas in the outer bulb from flowing into the arc tube, the material used for the arc tube (1) is expensive. There were drawbacks such as the need to use ozone-free quartz.

This invention was made in view of these conventional drawbacks, and a nonlinear capacitor is connected in parallel with one arc tube.
By installing this nonlinear condenser inside the outer tube or the cap.

Since it is possible to provide a pulse voltage that ensures reliable starting, it is possible to increase the pressure of the rare gas sealed in the arc tube, and it is also possible to use argon, krypton, etc. as rare gases, which were previously difficult.
It is now possible to use xenon-based gas, and the luminous flux maintenance rate is 0.
Luminous efficiency.

It is also possible to improve the fading characteristics.

The details of this invention will be explained below based on the drawings.

FIG. 3 is a diagram showing a circuit configuration of an embodiment based on the present invention, in which the circuit is a nonlinear capacitor connected in parallel with an arc tube (11).

Figure 4 is an example of a lamp configuration based on the circuit configuration of Figure 3, in which the nonlinear capacitor (2) is connected to the stem lead (14
a) A fixed connection is made between (ub) and (ub).

To briefly explain the operating function of this nonlinear capacitor aD, this type of capacitor made of barium titanate or the like is shown in FIG.

As the voltage V increases, the load Q also increases and the current flows,
When the 1 pressure V reaches a constant value v8, the charge Q is saturated and the +r current no longer flows. Therefore, when this capacitor is applied to the circuit shown in Figure 3, when the voltage of this capacitor (2) reaches v8, current will no longer flow, so the pulse voltage of Lπ (where L is the inductance of the ballast Ql) will become a ramp. is applied to The waveform of the applied voltage at this time is as shown in FIG. Based on Figure 3.

The peak voltage of the pulse was measured in combination with a high pressure mercury lamp ballast at 100W to toowt.

Table 1 shows the measurement results along with the ballast inductance.

Table 1 As is clear from Table 1, the capacitance of the capacitor is 100
If it is OFF or more, a peak voltage of #1soav or more can be obtained. In fact, a peak voltage of 5 oov or more clearly improves the starting characteristics. This is because, in the case of a combination of a nonlinear capacitor and a choke, the width of the peak voltage Ifi is much wider than that of a glow switch or the like.

For example, based on the circuit configuration shown in Figure 3, a 400W metal halide lamp is made, 39 Torr of rare gas is filled in the arc tube (1), a starting resistance of 30Ω is used, and 36nF is used. Nonlinear capacitor C21
We investigated the starting characteristics when + is connected and when a nonlinear condenser is not used. Ballast Q9 is a mercury lamp ballast for 400W, and the negative voltage is variable by slider.
The starting characteristics were investigated. Table 2 shows the preliminary results.

Table 2 In this way, nonlinear capacitors can generate wider pulses than glow switches and the like.

It can be said to be effective as a starter for metal halide lamps and high pressure sodium lamps, which have difficulty transitioning from glow to arc.

Further, the saturation voltage Va shown in FIG. 5 is desirably 2QV or more, and particularly when combined with a 200V choke, a saturation voltage Va in the range of 50V to 220V provides good starting characteristics. If the saturation voltage (v8) is smaller than 20V, the position where the pulse voltage Vp shown in FIG. 6 is superimposed will be close to 0 point in the secondary voltage waveform of the ballast. Therefore,
Since the lamp must be started using only the pulse voltage v'p itself, starting becomes uncertain and the load on the capacitor element is high, which is undesirable from the viewpoint of the life span and reliability of the element and the lamp.

Further, since a discharge lamp according to the present invention can apply a pulse having a sufficient height and peak value, a gas mainly composed of krypton or xenon can be used as the rare gas.

As mentioned above, it is possible to connect a nonlinear capacitor in parallel with the 0 arc tube and install this nonlinear capacitor inside the outer tube or inside the cap.

Since it is possible to provide a pulse voltage that ensures reliable starting, the pressure of the rare gas sealed in the arc tube increases, and furthermore,
This makes it possible to use rare gases such as krypton and xenon, and it also makes it possible to improve the luminous flux maintenance rate of 8, the luminous efficiency, and the extinction characteristics.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of a conventional lamp configuration, FIG. 2 is a circuit diagram thereof, FIG. 3 is a diagram showing an example of a circuit configuration obtained by implementing the present invention, and FIG. 4 is a diagram showing the lamp configuration. FIG. 5 is a diagram showing the operation of a nonlinear capacitor, and FIG. 6C is a diagram showing an applied voltage waveform in combination with a nonlinear capacitor and a choke. The same reference numerals indicate the same or equivalent parts. Agent Makoto Kuzuno - Figure 1 Figure 2 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] (1) A high-pressure metal vapor discharge lamp comprising an arc tube inside the outer bulb, a nonlinear condenser connected in parallel with the arc tube, and the nonlinear condenser installed inside the outer bulb or in the base. The high-pressure metal vapor discharge lamp according to claim 1, which uses a nonlinear capacitor having a capacity of +21 1000 P7 or more and a saturation voltage of 207 or more.