JPS61216232A - Metal halide lamp - Google Patents

Abstract

PURPOSE:To reduce a pulse voltage for starting and prevent damages of the fixture and the base, by sealing at least a kind of radioactive rare gas in a luminous tube, and furnishing an outside auxiliary conductor connected electrically to the electrode being close to the luminous tube. CONSTITUTION:The lamp consists of a luminous tube 11 which is a light transmitting housing a pair of electrodes and being sealed with mercury, a rare gas, and at least a metallic halide, and an outer tube 13 housing the luminous tube and an E shape base 14 with a maximum outer diameter at the screw portion less than 26.33mm. And in the luminous tube 11 is at least a kind of radioactive rare gas sealed, and is arranged an outer auxiliary conductor 21 connected electrically to the electrode 12b and close to the luminous tube 11. Since the lamp has the luminous tube 11 sealed with a radioactive rare gas, and the outer auxiliary conductor electrically connected to the electrode 12b, close to the luminous tube 11, the pulse voltage for starting can be reduced, and damages of the fixture and the base from the starting pulse voltage can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a metal halide lamp having an E-shaped cap (hereinafter referred to as a small cap of E26 type or smaller) with a threaded portion having a maximum outer diameter of 26 mm or less. .

Prior Art 27. In recent years, opportunities to use high-pressure discharge lamps such as metal halide lamps as light sources for indoor lighting have increased, and in conjunction with this, the development of low-wattage metal halide lamps is progressing.

An example of such a low wattage metal halide lamp is shown in FIG. In the figure, reference numeral 1 denotes an arc tube made of quartz, in which a pair of electrodes 2a and 2b are hermetically sealed, and an electrode 2a in which mercury, a rare gas, and a predetermined metal halide are sealed. is electrically connected to one terminal 6 of the cap 6 via the ribbon wire 3 and the stem wire 4, and the other electrode 2b is electrically connected to the other terminal of the cap 6 via the current supply line 7 and the stem wire 8. It is electrically connected to 9. 1o is an outer tube, to which a cap 6 is attached. Here, as the cap 6, a small cap of E26 type or smaller is used in accordance with the size of the lamp. For the dimensions of E26 type gold, please refer to JIS
As specified in C7709 "Types and dimensions of light bulbs and holders", the maximum outer diameter of the threaded part is 26.33 m.
m.

Such a low wattage metal halide lamp odor 3 Ha.
In the case of lamps, the surface area of the arc tube 1 and the area of the sealing part are large relative to the input power to the arc tube 1, so the rate of heat loss is greater than that of high-wattage metal halide lamps. As a result, efficiency decreases. Therefore, as shown in Figure 3,
The arc tube 1 is processed into an elliptical or spherical shape, and the sealing portion at the end is made as small as possible to reduce heat loss.

Problems to be Solved by the Invention However, if the arc tube sealing part is made smaller in this way, it becomes necessary to place the auxiliary electrode close to the main electrode, as is used in high-wattage lamps to reduce the starting voltage. Seal.

It becomes difficult to adopt this configuration. In order to solve this problem, a configuration is sometimes adopted in which a starter is built into the ballast or lamp, and a high voltage pulse generated by the starter is superimposed on the secondary voltage of the ballast to start the lamp. In this case, a pulse voltage of several kilovolts is usually required.

However, when a small cap of type E26 or smaller is used, the gap between the cap shell and the eyelet, or the gap between the socket holder and the threaded portion of the socket becomes extremely small.
By applying a high voltage pulse of V, a discharge may occur between them, causing damage to the instrument, and may also cause dielectric breakdown of the insulation used in the cap. As a countermeasure, there is a proposal to internationally stipulate the upper limit value of the starting pulse voltage when using these small caps.
Proposals have already been made. Furthermore, for smaller caps, the upper limit of the pulse voltage is expected to be even lower.

Conventional low-wattage metal halide lamps have the problem that, as mentioned above, the pulse voltage required for starting is several kilovolts, and therefore they cannot be started with a pulse voltage of 2.3 kilovolts or less.

The present invention solves the above-mentioned problem, and is a metal halide lamp that has a small cap of E2e type or smaller, and is capable of reducing the pulse voltage required for starting and preventing damage to the appliance and the cap due to the starting pulse. Its purpose is to provide lamps.

Means for Solving Problems 1 The present invention solves problems 1 and 0, 6*a
6K/luminescence), the tube is filled with at least one type of radioactive rare gas, and is electrically connected to an electrode and close to the arc tube 1, □. 3. picture,. Ah,. .

: □１ □ According to this configuration, 1 electron, 7,181 ions, 1.2ゎ, 7,000 ions, and 7,000 ions are generated in the arc tube by the ionizing effect of radiation from the enclosed radioactive rare gas.

'#MK[lIL? 11! □F. 3. 76°, yaw movement is easy, and since an external auxiliary conductor is provided close to the arc tube, a high electric field is generated between the electrode and the arc tube at the time of startup, and the above As a result of accelerating electrons and ions and making it even more likely to cause an electron avalanche, it is necessary to start the engine.
2t, E□Tga, -yoka87ah.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.
I will explain.

Figure 1 shows a low wattage class metallone 6 base according to the present invention.

This shows an example of a playing card, and the lamp rated power is 1
It lights at 60W with a rated power supply voltage of 200V using a shaped ballast in the starter.

In FIGS. 1(a) and 1(b), reference numeral 11 denotes an arc tube made of quartz, which is shaped into an ellipse in order to reduce the area of the crushed sealing portion and reduce heat loss. Luminous tube 11
A pair of electrodes 12a and 12b are hermetically sealed, and mercury and thulium iodide are contained inside.

Predetermined amounts of dysprosium iodide, holmium iodide, sodium iodide, and thallium iodide are each enclosed. Argon is sealed in the arc tube 11 as a starting gas, and a radioactive isotope of krypton (krypton-86) is sealed as a radioactive rare gas. The mixing ratio of argon and krypton-86 is set so that the radioactivity of the mixed gas is about 0.3 mCi (millicurie) per 11. Note that the pressure of the mixed gas sealed into the arc tube 11 is 150
It's Torz. Further, the maximum inner diameter of the arc tube 11 is 10.
6, the distance between the electrodes is 13.5++I++++.

13 is an outer tube with E26 type metal 14, and 7 ha/ Nitrogen is sealed inside at 350 Torr.

The electrode 12a is electrically connected to one terminal (eyelet) 17 of the cap 14 via a ribbon wire 16 and a stem wire 16, and the other electrode 12b is connected to the cap 14 via a current supply line 18 and a stem wire 19. It is electrically connected to the other terminal 2o.

Reference numeral 21 denotes an external auxiliary conductor disposed outside the arc tube 11 so as to be close to the electrode 12a, and is electrically connected to the stem wire 19°, that is, to the opposing electrode 12b via a normally closed bimetal switch 22. There is. Here, the external auxiliary conductor 21 is fixed to the movable contact side of the bimetal switch 22, and is arranged so that when the bimetal is bent by heat from the arc tube 11 while the lamp is lit, it moves in a direction away from the arc tube 11. It is designed to be electrically disconnected while the lamp is on.

Note that 23 is a getter, and 24 is a heat insulating film coated on the outer surface of the end of the arc tube 11.

In such a lamp, a radioactive rare gas is sealed in the arc tube 11, and the arc tube 1 is electrically connected to an electrode 12b.
1, the pulse voltage required for starting can be reduced.
It is possible to prevent damage to the appliance and the cap due to the starting pulse voltage.

Experimental examples related to the present invention will be described below.

First, 10 lamps as described in the above example were manufactured, and the pulse voltage required for starting them was measured. Specifically, the lamp was connected to a power source through a single ballast, and 180 V, which is 90 volts of the rated power supply voltage, was applied, and at the same time, a pulse voltage was superimposed on the secondary voltage of the ballast. The pulse half-width is 100μ crowns, the pulse phase is 46° and 2260 degrees with respect to the power supply voltage, and the pulse voltage (zero-peak value) is 1.
0kV to 4. The voltage was increased in 0.2 kV steps up to OkV. The measurement results are shown in Figure 2-4. As is clear from the figure, the lamp according to the present invention is fully started with a pulse voltage of 1.2 to 1.8 kV, and satisfies the upper limit of 2.3 kV currently proposed for all EQe type caps. be able to.

Page 9 On the other hand, in order to compare with the above example, a lamp (B) which is a conventional example in which only argon is sealed in the arc tube and does not have an external auxiliary conductor, and a lamp (B) which is also filled with argon and has an external auxiliary conductor are shown. Ten prototype lamps (q) and lamps (p) filled with a hyalbon-(krypton-85) mixed gas and without an external auxiliary conductor were made, and similar measurements were performed.The filling pressure was 150 Torr in both cases. And the radioactivity of the mixed gas in p) is about 0 as in the example.
．． It was set to 3 mci/l.

These results are shown in FIG. 2 (B)-p. In all cases, the starting characteristics were inferior to those of the lamp of this example. In particular, in IB), there were many lamps that did not start even when a pulse voltage of 4.0 kV was applied, and there were cases where discharge occurred within the socket of the appliance and damaged the metal parts of the socket. Further, in (to), there were some that required a pulse voltage of 2.3 kV or more, and the variation was large, so that the object of the present invention could not be achieved.

As described above, the lamp according to the present invention exhibits good starting characteristics, and the reason thereof will be discussed below.

First, regarding the effects of radioactive rare gases, for example, krypton-86 emits β-rays during nuclear decay, and these β-rays ionize the filled gas, so electrons and ions are always present in the arc tube. There is.

It is thought that these trigger an avalanche of electrons when starting the lamp, making it easier to start. On the other hand, regarding the effect of the external auxiliary conductor placed close to the two arc tubes, this creates a high electric field between them and the electrodes during startup.

It is thought that the electrons and ions generated by the radioactive rare gas mentioned above are accelerated by this high electric field and have the function of growing an electron avalanche. By using these two together,
This makes it possible to realize a lamp that can be started with a low pulse voltage.

In the above embodiment, a 150W lamp was explained, but the present invention is even more effective for a lamp of 10oW or less.

Further, the present invention can be applied not only to lamps using a shaped ballast in the starter, but also to lamps in which a starter, such as a lighting tube, is built into the lamp.

Regarding the type of radioactive rare gas, not only krypton-85 but also argon-39, argon-42, and other radioactive isotopes may be used.

The encapsulated iodide is also not limited to this example. Furthermore, the external auxiliary conductor may also be of a type other than this embodiment.

DETAILED DESCRIPTION OF THE INVENTION As described in detail, the present invention provides a metal halide lamp having a small base of E26 type or smaller, in which at least one kind of radioactive rare gas is sealed in the arc tube, and the lamp is electrically connected to an electrode and is close to the arc tube. By providing an external auxiliary conductor, it is possible to provide a metal halide lamp that can reduce the pulse voltage required for starting and prevent damage to the fixture and base due to the starting pulse.

[Brief explanation of drawings]

Figures 1 (a) and (b) are front and side views of a metal halide lamp which is an embodiment of the present invention, Figure 2 is a characteristic diagram showing the distribution of pulse voltage required to start the lamp, and Figure 3 is a diagram showing the distribution of pulse voltage required to start the lamp. FIG. 2 is a front view of a conventional metal-no-ride lamp. 11... Arc tube, 12a, 13b...
Electrode, 13... Outer tube, 14... Cap,
21...External auxiliary conductor. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure (c) (εri (C)
(I) Figure 3

Claims (1)

[Claims] An arc tube comprising a light-transmitting container containing a pair of electrodes and mercury, a rare gas, and at least one metal halide sealed therein;
．． an outer tube having an E-shaped cap of 33 mm or less; at least one kind of radioactive rare gas is sealed in the arc tube; and auxiliary conductors are electrically connected to the electrodes and located close to the arc tube. A metal halide lamp characterized by: