JPS6273549A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To reduce generation of irregular flickering by fully performing focusing of an electron current during the process of discharging by means of rod- shaped auxiliary electrodes. CONSTITUTION:The lead wires 3 and 3 of a mount 1 are provided with the rod-shaped auxiliary electrodes 7 and 7 projected from an electrode filament 4 toward a discharge space, while the auxiliary electrodes 7 and 7, whose base parts are fixed to the lead wires 3 and 3 by electric welding, form the fixed points 8 and 8. The rod-shaped auxiliary electrode 7 is located at the fixed point 8 on the edge or its outside of an imaginary cone having the fixed point 8 as its top, the line segments shown by (a)-(d) as its edges and having a vertex angle theta of 60 deg.. The axis A of the imaginary cone is in parallel to the axis of the electrode filament 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a fluorescent lamp that can prevent irregular flickering during alternating current lighting and is suitable for mass production.

[Technical background of the invention and its problems]

When a fluorescent lamp is turned on with alternating current, you may notice fluctuations in the emitted light from the fluorescent lamp. The fluctuation of the emitted light, that is, the flicker K, is a regular flicker that occurs in response to the frequency of the AC power source of the fluorescent lamp.

There is irregular flickering, in which the brightness fluctuates irregularly regardless of frequency, and the latter irregular flickering causes discomfort to fluorescent lamp users. It is known that this irregular flickering occurs when the polar movements inside the fluorescent lamp repeat irregularly.
When the lamp was lit for about 1,000 hours or more, the occurrence of irregular flickering became noticeable and visible to the naked eye, and the user tended to feel uncomfortable.

The discharge electrode of a conventional fluorescent lamp has an electron-emitting substance coated in the center, leaving the end of the electrode filament of a tungsten coil connected to a lead wire planted in the stem, and the discharge electrode becomes an anode. When this occurs, one end of the electrode filament to which the electron emitting material is not coated and one lead wire capture electrons flying from the cathode. The electron-emitting material of the discharge electrode is consumed as the fluorescent lamp is lit, and the area where the electron-emitting material is not deposited gradually expands. It is thought that it becomes difficult to focus the electron flow only on a certain point, and therefore irregular occurrence and disappearance of anode vibration becomes more likely to occur.

As a measure to prevent irregular flickering caused by the irregular occurrence and disappearance of the anode vibration of a fluorescent lamp, a rod-shaped auxiliary electrode is placed close to the electrode filament as disclosed in Japanese Patent Application Laid-open No. 60-14740. What has been established is known. Since the auxiliary electrode focuses the electron flow during discharge, the electron emitting material of the electrode is not consumed by the electron flow, resulting in stable generation of anode vibration and thus preventing irregular flickering of the fluorescent lamp. It worked.

However, if the rod-shaped auxiliary electrode is supported by the lead wire along the surface including the lead wire and the electrode filament at a right angle to the lead wire or at an angle close to it, the auxiliary electrode tends to come close to the inner wall of the glass bulb, and the electrode filament during discharge If the inner wall of the bulb becomes dirty due to sputtering of the auxiliary electrode component, or if the center axis of the electrode deviates from the center axis of the glass bulb, the inner wall of the glass bulb is likely to become fouled, and the auxiliary electrode may cause fluorescence on the inner wall of the glass bulb. There is a problem of scratches on the phosphor coating due to contact with the body coating. Also, the auxiliary electrode is close to the electrode filament.

If the temperature is too high, the area where the auxiliary electrode is welded to the lead wire will heat up as the fluorescent lamp discharges.

There was a risk that it would be undesirably released into the game lamp and inhibit the discharge. Undesirable CO-based gas is generated when the electron emitting material of the electrode filament is activated during the manufacture of fluorescent lamps, but if the end of the electrode filament where the electron emitting material is adhered is close to the auxiliary electrode. The auxiliary electrode was sometimes attacked by the above gas.

Further, when the auxiliary electrode is separated from the electrode filament and its tip is displaced outside the discharge space of the electrode filament, the effect of capturing electrons becomes weaker and irregular flickering is more likely to occur, resulting in undesirable results.

[Purpose of the invention]

The present invention has been made to prevent the above-mentioned drawbacks.
Since the rod-shaped auxiliary electrode sufficiently focuses the electron flow during discharge, it reduces the occurrence of irregular flickering, and also prevents contamination of the glass bulb due to spatter of the auxiliary electrode. The purpose is to provide the industry with an improved fluorescent lamp that is not susceptible to corrosion.

[Summary of the invention]

In the present invention, the mount is provided with a rod-shaped auxiliary electrode that protrudes from the electrode filament into the discharge space, and the auxiliary electrode is fixed to a lead wire, and in the vicinity of the fixed point, the auxiliary electrode has the fixed point as the apex, and the auxiliary electrode is fixed to the lead wire. This fluorescent lamp is characterized in that the apex angle of a virtual cone whose axis is a line passing through the point and parallel to the electrode filament is located at a position of 10° or more.

[Embodiments of the invention]

The details of the invention will be explained with reference to the accompanying drawings.

Mounts are provided at both ends of a glass bulb (not shown) whose inner surface is coated with a phosphor coating. FIG. 1 is a partially cutaway front view of a mount sealed to both ends of a glass bulb in an embodiment of the fluorescent lamp of the present invention.

FIG. 2 is a side view thereof.

The mount (1) is attached to the stem (2) and the lead wire (3).

(3) A polar filament (4) is connected to and supported by K, and an electron emitting material is coated on the polar filament (4) to form an electron emitting material coated part (5) and a non-coated part. (6
) are configured. IJ of the above mount (1) -
)' line (31.

(3) is provided with rod-shaped auxiliary electrodes (7), (7) protruding from the electrode filament (4) toward the discharge space.

The auxiliary electrode (71, +7) has its base connected to the lead wire (
3).

(3) K electric welded and fixed fixed point (8),
+8). (9) is the exhaust hole 0υ that communicates with the exhaust pipe aQK.

aυ is an external lead electrically conductively connected to the lead wires (3), (3). The rod-shaped auxiliary electrode (the force is applied at the fixed point (8) with the fixed point (8) as the apex)
, (hl, (cl, ) is parallel to the axis of the bar-shaped auxiliary electrode (5).
The length h (mm) protruding from the electrode filament (4) toward the discharge space is at least 4 lengths, for example, 10 m. Also, the tip of the rod-shaped auxiliary electrode (7) should be at a distance of 6 or less, for example 5
i, the distance (n) between the tips of the auxiliary electrodes is 101)1)
It has become.

According to experiments by the present inventors, if the rod-shaped auxiliary electrode is located within a virtual cone with an apex angle smaller than 60'' with the above-mentioned fixed point as the apex, the inner surface of the mount is coated with phosphor during the earth-laying process during fluorescent lamp manufacturing. When inserted into a glass bulb coated with phosphor, the rod-shaped auxiliary electrode comes into contact with the phosphor coating and is likely to cause scratches.Also, since the rod-shaped auxiliary electrode is close to the bulb wall, the electrode material may spatter during discharge, damaging the bulb. It turned out that this was not possible because it would cause blackening to appear on the wall.

It is preferable that the rod-shaped auxiliary electrode protrudes from the electrode filament to the discharge space side by at least 4 fi or more. If this protrusion length is less than 41)1, the focusing of the electron flow at the auxiliary electrode becomes uncertain, and the electron flow does not reach the electrode filament. Because some of the electrons become focused easily, the electron flow focusing point moves unstable due to the consumption of the electron emitting material in the electrode, and therefore the anode vibration becomes unstable pressure.

This is not preferable because flickering is likely to occur.

In addition, the tip of the rod-shaped auxiliary electrode is located 6 minutes from the axis of the glass bulb.
It is preferable that the electron current is within am, and the above structure can prevent the electron flow from being focused on the electrode filament.

The rod-shaped auxiliary electrode should be at least 2 m from the part of the electrode filament where the electron emitting material is coated, and 0.5 mm from the part where the electron emitting material is not coated.
If the distance is greater than this, the anode bright spot will be generated in a relatively short time even after the fluorescent lamp has been lit for more than t,ooo hours, and the discharge will start quickly.

Further, it is preferable that the rod-shaped auxiliary electrode be separated from the inner wall of the glass pulp by at least 3 m1.If the size is smaller than 3u, the bulb is likely to blacken due to sputtering of the material of the rod-shaped auxiliary electrode.

〔Effect of the invention〕

As described in detail above, the present invention is characterized in that an electron emitting material is coated on both ends of a glass bulb whose inner surface is coated with a phosphor coating.
A mount is provided with an electrode filament supported on a main lead wire, the mount having a rod-shaped auxiliary electrode projecting from the electrode filament into the discharge space by a length of at least 4 mm, and the auxiliary electrode is connected to the lead wire. In the vicinity of the identification point, the auxiliary electrode is located at a position where the apex angle of a virtual cone with the fixed point as the apex and the axis passing through the fixed point and parallel to the electrode filament is 60'' or more. This fluorescent lamp is characterized by the fact that it can stably generate anode vibration even as the lighting time of the fluorescent lamp passes, and therefore there is no occurrence of irregular flickering. It is possible to obtain stable optical characteristics with less occurrence of blackening, and since the rod-shaped auxiliary electrode does not come close to the inner wall of the glass bulb, it is possible to prevent the inner wall of the bulb from being contaminated by electrode spatter. There is no possibility of scratches due to contact with the phosphor coating, and there is less risk of the auxiliary electrode being attacked by gas during activation of the electron emitting material.
Since the auxiliary electrode is configured to cover the front surface of the electrode, it can sufficiently capture electrons, which has the effect of preventing irregular flickering.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view of a mount sealed to both ends of a glass bulb of an embodiment of the fluorescent lamp of the present invention, and FIG. 2 is a side view thereof. 1...Mount, 3...Lead wire. 4... Electrode filament.

Claims (2)

[Claims] (1) A glass bulb whose inner surface is coated with a phosphor coating is provided with mounts having electrode filaments coated with an electron-emitting substance and supported by two lead wires at both ends of the mount, is equipped with a rod-shaped auxiliary electrode projecting from the electrode filament into the discharge space by a length of at least 4 mm, the auxiliary electrode being fixed to a lead wire,
In the vicinity of the fixed point, the auxiliary electrode is located at a position where the apex angle of a virtual cone whose apex is the fixed point and whose axis is a line passing through the fixed point and parallel to the electrode filament is 60° or more. Features fluorescent lamps. (2) Claim 1, characterized in that the distance between the tip of the rod-shaped auxiliary electrode and the glass bulb axis does not exceed 6 mm.
Fluorescent lamps as described in section.