JP2002298609A - Bulb-shaped fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bulb-shaped fluorescent lamp prevented from a flicker generated when lighting. SOLUTION: A bulb 21 with an inner diameter of not less than 5 mm and not more than 10 mm is installed. A main amalgam 33 including mercury is enclosed in the bulb 21. A rare gas containing neon gas with the distribution ratio of more than 80% is enclosed in the bulb with a pressure of 240 Pa-2,000 Pa. A pair of filament electrodes are airtightly mounted at both ends of the bulb. When lighted, a lamp current of 100 mA-250 mA is made to flow between the filament electrodes. A lamp current of 2 mA-10 mA is made to flow between the filament electrodes at the time of light control lower limit. Here, the lamp current is a discharge current flowing between the filament electrodes. A light emitting tube 5 is lighted at the time of lighting, and at the time of light control lower limit respectively. It is confirmed by an experiment that the light emitting tube 5 does not generate any striation. The flicker of the light emitting tube 5 when lighting, can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp having a bulb in which mercury amalgam is sealed.

[0002]

2. Description of the Related Art Conventionally, a bulb-type fluorescent lamp of this type has a bulb in which a plurality of substantially U-shaped tubes are sequentially connected to form a bent discharge path. The bulb is filled with mercury amalgam. Further, the composition ratio of argon (Ar) gas is 100% in this valve.
% Or a rare gas having a composition ratio of neon (Ne) gas of about 50% is sealed. A pair of filament electrodes is sealed at both ends of the bulb.

[0003]

However, in this bulb-type fluorescent lamp, the discharge of the rare gas concentrates in the central region due to the extremely low mercury vapor pressure near the lower limit of dimming. When the light emitting tube is lighted, there is a problem that an unstable light emission phenomenon such as a moving stripe called a striation occurs when the light emitting tube is turned on.

[0004] The present invention has been made in view of the above points, and relates to a compact fluorescent lamp capable of preventing flicker during light emission.

[0005]

According to a first aspect of the present invention, there is provided a bulb-type fluorescent lamp comprising a bulb having an inner diameter of 5 mm to 10 mm, a mercury amalgam sealed in the bulb, and a pressure of 240 Pa to 2000 Pa in the bulb. Is stopped, a rare gas having a composition ratio of neon gas of 80% or more, and 100 mA to 250 mA sealed at both ends of the bulb and turned on.
, An arc tube having a pair of filament electrodes through which a lamp current of 2 mA to 10 mA flows at the time of the dimming lower limit; a lighting circuit for lighting the arc tube; and a lighting circuit for supporting the bulb of the arc tube and supporting the bulb. And a base attached to the cover.

In this configuration, mercury amalgam is sealed in a valve having an inner diameter of 5 mm or more and 10 mm or less, and a rare gas having a neon gas composition ratio of 80% or more is sealed in the valve at a pressure of 240 Pa to 2000 Pa. Stop. Further, a pair of filament electrodes is sealed at both ends of the bulb. In this state, when lighting, 100 mA
A lamp current of ２５０250 mA flows between the filament electrodes, and a lamp current of 2 mA to 10 mA flows between the filament electrodes at the lower limit of dimming. The lamp current refers to a discharge current flowing between a pair of filament electrodes. Under these conditions, when the arc tube was lit at the time of lighting and at the time of the dimming lower limit, it was confirmed by an experiment that striation did not occur in this arc tube. Therefore, it is possible to prevent flickering of the arc tube when the arc tube is turned on.

A bulb-type fluorescent lamp according to a second aspect of the present invention is the bulb-type fluorescent lamp according to the first aspect, wherein the bulb has a total length of 100 mm or less and a rare gas of 240 Pa or more.
The bulb is sealed in the bulb at a pressure of 00 Pa or less, and the filament electrode is formed of an oxide obtained by applying an emitter to tungsten. When the power consumption of the arc tube is WL and the surface area of the filament electrode is S, S < 1.7 × WL−
It is configured to satisfy the relationship of 1.7.

In this structure, the total length is 100 mm.
A rare gas is sealed in the following valve at a pressure of 240 Pa or more and 1200 Pa or less. Next, when the surface area of a filament electrode formed of an oxide obtained by applying an emitter to tungsten is defined as S, and the power consumption of the arc tube is defined as WL,
This filament electrode is sealed at both ends of the bulb so as to satisfy the relationship of 1.7 × WL−1.7. Here, the surface area S of the filament electrode is defined as the area of the outer surface where the emitter and the filament are exposed when the emitter is applied. As a result, experimentally, thermionic emission increased,
By suppressing the preheating current (filament current), the luminous efficiency of the bulb is increased, and sometimes the thermoelectrons in the dimmed lighting state are secured, thereby suppressing the disappearance of the emitter due to the sputtering of the filament electrode and the life of the arc tube. Can be made longer and the size can be further reduced. It is particularly effective at dimming lighting.

[0009] In the bulb-type fluorescent lamp according to the third aspect of the present invention, in the bulb-type fluorescent lamp according to the first or second aspect, the filament electrode includes a carbonate of an alkaline-earth metal and an alkaline-earth metal and a transition metal. It holds a mixture with a body and is formed by thermal decomposition and activation in a vacuum atmosphere.

In this configuration, the filament electrode holds a mixture provided by mixing a carbonate of an alkaline earth metal with a sintered body containing an alkaline earth metal and a transition metal. By activating and forming a filament electrode, the fired body is an electron emitting material and has resistance to sputtering, so even if the lamp current is reduced particularly during dimming lighting, without decreasing the electron emitting ability, It is possible to extend the life of the filament electrode of the light bulb type fluorescent lamp capable of dimming and lighting.

According to a fourth aspect of the present invention, there is provided the bulb-type fluorescent lamp according to the third aspect, wherein the sintered body includes at least one of barium, strontium and calcium and at least one of tantalum and niobium. And / or oxynitride.

In this configuration, if the sintered body is made of an oxide and / or an oxynitride containing at least one of barium, strontium and calcium and at least one of tantalum and niobium, the electron emission capability It is possible to more easily implement a filament electrode having a longer life without lowering the life.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIGS. 1 to 3 show a first embodiment of the present invention. FIG. 1 is a sectional view of a bulb-type fluorescent lamp, and FIG. 2 is a plan view of an arc tube and a partition of the bulb-type fluorescent lamp. FIG. 3 is a development view of the bulb of the arc tube.

In FIG. 1, reference numeral 1 denotes a bulb-type fluorescent lamp,
This bulb-type fluorescent lamp 1 is a dimmer compatible type. Also,
The light bulb shaped discharge lamp 1 includes an envelope having a cover 2, a base 3 and a globe 4. A fluorescent lamp device 7 having a light emitting tube 5 and a lighting circuit 6 is accommodated in the envelope. The envelope has, for example, an outer shape that is close to the standard size of a mini krypton type light bulb.

The bulb-shaped light emitting lamp 1 has a height dimension from the base 3 to the globe 4 of about 81 mm, and a width dimension corresponding to the maximum diameter portion of the globe 4 of about 4 mm.
It is about 5 mm. Hereinafter, one end side of the cover 2, that is, the base 3 side is described as an upper side, and the other end side, that is, the glove 4 side is described as a lower side.

Next, the cover 2 is provided with a substantially cylindrical base 11 which expands downward. An annular partition 12 is attached to the lower end of the base 11. The base 11 and the partition 12 are made of, for example, a heat-resistant synthetic resin such as polybutylene terephthalate (PBT). In addition, the partition body 12 is formed of a cylindrical tubular portion (not shown) and a disk-shaped partition plate (not shown) formed inside the tubular portion. Further, a plurality of mounting holes (not shown) for mounting the arc tube 5 are formed in the partition plate at equal intervals along the same circumference.

The base 3 is an Edison type E17.
The upper end of the base 11 is covered with a mold or the like, and is fixed with an adhesive or a caulking.

The globe 4 is made of a transparent or light-diffusing milky white glass or synthetic resin, and is formed in a substantially spherical shape approximating the shape of a glass bulb of a mini krypton type bulb. In addition, this glove 4
An opening 14 is formed in a part of the opening 14.
A fitting edge 15 which is fitted inside the opening 14 at the lower end of the partition 12 of the cover 2 and is adhered by an adhesive is formed at the edge of the cover 2. The globe 4 may be combined with another member such as a diffusion film to improve the uniformity of luminance, or may be omitted.

The arc tube 5 has a glass bulb 21 as shown in FIGS. This valve
For example, a three-wavelength type phosphor is applied to the inner surface of 21. The bulb 21 is filled with a rare gas G as a discharge gas or a sealing gas containing mercury (Hg). This rare gas G is 80% neon (Ne) gas.
A mixed gas occupying the above, specifically, a mixed gas of 97% neon gas and 3% argon (Ar) gas. And this rare gas G is 240 Pa to 2000 Pa, preferably 600 Pa to 2000 Pa, specifically 1200 Pa.
It is sealed in the valve 21 at a pressure of about Pa.

Further, the arc tube 5 is set to 100
About mA to 250 mA, preferably 100 mA to 200
A lamp current of about mA flows, and 2 mA to
A lamp current of 10 mA flows. Here, the lamp current refers to a discharge current flowing between the filament electrodes 22.

At both ends of the bulb 21, a pair of filament electrodes 22 forming a pair are sealed by, for example, a pinch seal. The valve 21 has three tubes 23a, 23b, 23c having substantially the same shape. These tubes 23a, 2
3b and 23c are, for example, substantially cylindrical glass tubes having an outer diameter of 8 mm or less, specifically about 6.5 mm, and an inner diameter of 5 mm or more and 10 mm or less, specifically about 5.2 mm. Are formed in a substantially U-shape having a top portion which is curved at an intermediate portion. That is, each of these tubes 23a, 23b, 23c
It is composed of a bent portion 24 that is curved, and a pair of straight pipe portions 25 that are continuous with the bent portion 24 and that are parallel to each other. Further, these pipes 23a, 23b, 23c have a substantially U-shaped state, and the length of the bent portion 24 and the end in the height direction is about 35 mm.

The vicinity of the adjacent ends of the tubes 23a, 23b and 23c are connected in series by a communication tube 26 to form one continuous discharge path 27. This communication pipe 26 is connected to each pipe 23
Openings formed by heating and melting the connected end portions of a, 23b, and 23c and then blowing them apart are connected. And the straight pipe part 25 of each pipe body 23a, 23b, 23c
Are positioned at equal intervals on the same circumference centered on the central axis of the bulb-shaped fluorescent lamp 1, that is, the straight pipe portions 25 of the respective tubes 23a, 23b, 23c correspond to the respective vertices of the hexagonal cross section. Are located.

Each of the tubes 23a, 23b, and 23c has one end sealed by a line seal using a mount or a pinch seal without using a mount, and has a cylindrical end, also called an exhaust pipe, at the other end. Each of the narrow tubes 28 is provided so as to protrude in a communicating state. These thin tubes 28 are provided so as to protrude from the end opposite to the end where the filament electrode 22 is sealed, that is, the end on the non-filament electrode 22 side. Further, each of these thin tubes 28 is sequentially sealed by fusing during the manufacturing process of the valve 21, the inside of the valve 21 is exhausted through an unsealed part of each of the thin tubes 28, and the rare gas G is sealed. After the replacement, the capillaries 28 are sealed by fusing out an unsealed part.

Further, each filament electrode 22 has a filament coil 31, and the filament coil 31 is supported by a pair, ie, two linear wells 32. Each of these wells 32 is, for example, tubular bodies 23a, 23c at both ends.
Is connected to a wire 35 that is led out of the ends of the tubes 23a and 23c at both ends and connected to the lighting circuit 6 via a dumet wire sealed with a pinch seal or the like.

A main amalgam 33 as a mercury amalgam is sealed in the thin tube of the tube 23a at one end when the thin tube 23a is sealed. The main amalgam 33 is an alloy composed of bismuth (Bi), indium (In) and mercury (Hg), is formed in a substantially spherical shape, and controls the mercury vapor pressure in the valve 21 to an appropriate range. Has an action. Specifically, the main amalgam 33 has a mass ratio of mercury to indium of 6%.

The main amalgam 33 may be made of an alloy obtained by combining tin (Sn), lead (Pb), etc. in addition to bismuth and indium. Also,
Auxiliary amalgam 34 plated with indium (In) is attached to one of the wells 32 of each filament electrode 22, and sealed in each of the tubes 23a and 23c.

The ends of the tubes 23a, 23b, 23c of the valve 21 are inserted into the respective mounting holes of the partition 12, and an adhesive such as silicone resin is filled from the inside of the partition 21. As a result, the ends of the tubes 23a, 23b, and 23c and the partition 21 are fixed to each other.

Further, among the ends of the tubes 23a, 23b, 23c of the bulb 21, the filament electrodes 22 of the tubes 23a, 23c at both ends are provided.
Are disposed at both ends of the bulb 21.The ends of the tubular bodies 23a and 23c at both ends where the filament electrode 22 is not disposed and the end of the intermediate tubular body 23b are located at the middle of the bulb 21. End 37 located in the middle, the communication pipe of each intermediate end 37
The end side from 26 is a place deviated from a single discharge path 27 constituted by the respective tubes 23a, 23b, 23c and the communication tube 26.

As shown in FIG. 1, the lighting circuit 6
A substantially disk-shaped substrate 41 is provided in the base 11 of the cover 2. A plurality of electrical components are mounted on both surfaces of the substrate 41, that is, on the upper surface on the base 3 side and on the lower surface on the globe 4 side, to form an inverter circuit for lighting the arc tube 5 at high frequency, that is, a high-frequency lighting circuit. Also,
On the upper surface of the substrate 41, an electric component 42 such as a large electrolytic capacitor or a film capacitor, which is relatively weak to heat, that is, has low heat resistance, is arranged. On the lower surface of the substrate, a rectifying element (REC) having a relatively high heat resistance, that is, a rectifying element (REC) having high heat resistance and a small height, a chip-like electric component such as a transistor, a resistor, etc. Of chip components 43 are arranged.

Further, the substrate 41 is fixed by not-shown locking claws provided inside the base 11 of the cover 2. When the light bulb shaped fluorescent lamp 1 configured as described above was turned on at an ambient temperature of 25 ° C., the lamp current when all the lights were turned on was 200 mA, and the total luminous flux was 1370 lm.
When the bulb-type fluorescent lamp 1 was turned on at an ambient temperature of 25 ° C., the dimming lower limit, that is, the lamp current was 5 mA, and the total luminous flux was 80 lm.

When the bulb-type fluorescent lamp 1 is turned off, power is supplied to the base 3, and a lighting circuit 6 applies a lamp lighting voltage between the filament electrodes 22 at both ends of the bulb 21, thereby causing the light emitting tube to emit light. 5 is turned on.

Here, in the case of the bulb-type fluorescent lamp 1 using the arc tube 5 filled with a rare gas containing 100% of argon, the lamp current value flowing through the arc tube 5 is changed to change the lamp current value. When dimming the light emitted from 5,
The discharge concentrates in the central area of the bulb 21, causing striation. This is because the mass of argon used as the rare gas G is heavy. Therefore, flicker can be prevented by using neon having a relatively light mass as much as possible.

Therefore, each of the tubes 23a, 23a,
The inner diameter of 23b and 23c is set to 5 mm or more and 10 mm or less, the neon gas constituent ratio in the rare gas G sealed in the valve 21 is set to 80% or more, and the rare gas G is
40 Pa to 2000 Pa, preferably 600 Pa to 20
The bulb-shaped fluorescent lamp 1 is provided by being sealed at a pressure of 00 Pa.

The bulb-type fluorescent lamp 1 is operated at an ambient temperature of 25 ° C. and a lamp current of 200 mA when all light is turned on.
And the total luminous flux was 1370 lm. In addition, this light bulb shaped fluorescent lamp 1 had an ambient temperature of 25 ° C., a dimming lower limit, that is, a lamp current of 5 mA, and a total luminous flux of 80 lm. At this time, at the time of all-light lighting and the lower limit of dimming,
No visible flickering of light emission and no moving stripes called striation were observed.

As a result, experimentally, the bulb-type fluorescent lamp 1
100mA-250m when all light is on
A lamp current of A, 2mA to 10mA at dimming lower limit
Since the striation does not occur in the bulb 21 of the bulb-type fluorescent lamp 1 by flowing this current, it is possible to prevent the bulb 21 from flickering when the bulb 21 emits light.

Next, FIGS. 4 to 7 show a second embodiment, FIG. 4 shows a filament coil of a bulb-type fluorescent lamp, (a) is an explanatory view of a completed double coil, and (b) FIG. 5 is a diagram illustrating a filament coil, FIG. 5 (a) is a diagram illustrating a completed triple coil, FIG. 5 (b) is a diagram during manufacture, and FIG. And FIG.
7A shows a filament coil, FIG. 7A is an explanatory diagram of a completed stick coil, and FIG.
Is a graph showing the relationship between the filament coil surface area and the preheating power.

The bulb-type fluorescent lamp 1 has an overall length of 100 mm or less, and the bulb 21 of the bulb-type fluorescent lamp 1 has an outer diameter of 6.5 mm and an overall length of 35 mm.
It is. The inner surface of the bulb 21 is coated with a three-wavelength phosphor (not shown).

In order to further reduce the size of the bulb-type fluorescent lamp 1, the tubes 23a, 23b and 23c of the bulb 21 must be made thinner. It is necessary to make the discharge path 27 longer. However,
Conventionally, a tungsten coil is fixed to two lead wires, and barium oxide is attached to this tungsten coil.
(BaO), calcium oxide (CaO), and a filament coil 31 coated with an electron-emitting substance containing strontium oxide (SrO) as a main component are attached as the filament electrode 22, so that the tubes 23a, 23b, and 23c of the bulb 21 are provided. If the length of the coil 21 is reduced, the total length of the coil 21 must be shortened.

The life of the bulb-type fluorescent lamp 1 of this type depends on the amount of the electron-emitting substance held in the filament coil 31. Therefore, when the amount of the electron discharge substance held by the filament coil 31 is reduced, the lamp life is shortened. Therefore, when the tubes 23a, 23b and 23c of the bulb 21 are made thinner and the total length of the filament coil 31 is shortened, the holding amount of the emitter is reduced and the lamp life is shortened.

Further, since the filament electrode 22 using the filament coil 31 coated with the electron emitting material becomes extremely hot at the time of starting the lamp or at a steady state, the filament coil 31 or a lead wire for fixing the filament coil 31 is used. Is in contact with the inner wall of any of the tubes 23a, 23b, 23c, or very close to the inner wall of any of the tubes 23a, 23b, 23c, the A hole is opened in one of them, and the arc tube 5 cannot be turned on. In other words, if the long filament coil 31 is forcibly stretched in the thin tubes 23a, 23b, 23c, the lamp life will be shorter.

Therefore, when a thin arc tube 5 is used, the application amount of the emitter is limited. Therefore, in order to secure the lamp life with a small amount of emitter, the filament coil 31 may be preheated during steady lighting. It is effective to set the preheating temperature at this time to a temperature at which thermoelectrons can be sufficiently extracted, that is, about 800 ° C.

In particular, when the bulb-type fluorescent lamp 1 is lit and lit, the lamp current is reduced to 2 mA to 10 mA, so that the filament electrode 22 is not properly heated by electric discharge, so that the filament coil 31 is preheated. Needs to be performed sufficiently.

However, if the filament coil 31 is heated during steady lighting, extra power is consumed by the amount of power required for preheating. Therefore, the filament coil
The lamp efficiency is lower than when no preheating voltage is constantly applied to 31.

Therefore, thin tubes 23a, 23b, 23c are used to increase the lamp efficiency, and preheating is always applied to the filament coil 31 in order to secure the lamp life, so that power loss due to the preheating is always minimized. Therefore, it is necessary to set the approximate surface area of the filament coil 31 to an appropriate value.

Therefore, the filament coil attached between the filament electrodes 22 of the arc tube 4 of the bulb-type fluorescent lamp 1
31 is tungsten with oxide emitter applied on the surface
In the case of a coil obtained by spirally winding a single wire made of (W), that is, in the case of a single coil not shown, the wire diameter of the single wire of this single coil, that is, the main wire diameter is set to FD, and the single wire of this single coil is connected to a mandrel. The coil inner diameter of this single coil when spirally wound, that is, the mandrel diameter was defined as MD.

Further, the filament coil 31 spirally winds the single coil 52 around a piano wire having a wire diameter PD to form a double coil 53. In this case, the emitter is applied to the double coil 53 so that the gap formed by the single coil 52 is filled with the emitter. The surface area S of the double coil 53 is defined as S = π × (2 × FD + MD) × L1, where L1 is the total length of the single coil 52 on which the emitter is assumed to extend on a straight line.

Further, as shown in FIG. 5, the sub-wires are formed so that the filament coil 31 forms a substantially circular primary mandrel 55 around a tungsten main wire 54.
The first coil 57 is spirally wound to form a first coil 57, and the first coil 57 is further spirally wound so as to form a secondary mandrel 58 to form a second coil 59. In the case of a coil formed by further winding a piano wire having a wire diameter PD, that is, in the case of the triple coil 60, the emitter is applied so that the gap formed by the double coil is filled with the emitter. The surface area S of the triple coil 60 is determined by the diameter of the subwire 56,
That is, the sub-wire diameter is FD1, the wire diameter of the main wire 54, ie, the main wire diameter is FD2, and the wire diameter of the primary mandrel 55, ie, the first mandrel diameter is MD1, and the wire diameter of the secondary mandrel 58, ie, the second mandrel diameter. Is defined as MD2 and the total length of the portion of the second coil 59 where the emitter is applied (the length when it is considered to be linearly extended) is defined as L2. S = π × (4 × FD1 + 2 × MD1 + MD2) × L2 ( Suppose that S = π × (4 × FD1 + 2 × FD2 + MD2) × L2 (if MD1 <FD2).

As shown in FIG. 6, the filament coil 31 forms a substantially circular primary mandrel 55 around a tungsten (W) main wire 54 having an oxide emitter coated on its surface. In the case of a stick coil 61 formed by spirally winding the sub-wire 56 to form a first coil 57 and further spirally winding the first coil 57 so as to form a secondary mandrel 58,
The emitter is applied so that the gap formed by the stick coil 61 is filled with the emitter. The surface area S of the stick coil 61 is defined as the wire diameter of the sub-wire 56, that is, the sub-wire diameter is FD1, the wire diameter of the main wire 54, that is, the main wire diameter is FD2, and the wire diameter of the primary mandrel 55, that is, the first mandrel diameter. Let MD1 be the diameter of the secondary mandrel 58, that is, the diameter of the second mandrel.
When MD2 is set and the total length of the portion where the emitter is applied to the stick coil 61 is set as L2, S = π × (4 × FD1 + 2 × MD1 + MD2) × L2 (when MD1> FD2) S = π × (4 × FD1 + 2 × FD2 + MD2) × L2 (when MD1 <FD2).

The surface area S of the filament electrode 22 is:
The area of the outer surface where the emitter and the filament are exposed when the emitter is applied.

Here, the electric power required to heat each filament coil 31 to a target temperature generally depends on the surface area of each filament coil 31. This is because radiation loss and gas loss predominate in the heat loss of the filament coil 31, which depend on the surface area of the filament coil 31. Therefore, in order to reduce the preheating power of the filament coil 31, the smaller the surface area of the filament coil 31, the better.

In particular, in the case of the bulb-type fluorescent lamp 1, since the power consumed by the arc tube 5 is relatively small, about 5 W to 30 W, it is desirable that the power consumed by preheating be as small as possible.

The electric power allowed in this compact fluorescent lamp is about 10% of the electric power of the arc tube 5. That is, assuming that the power consumption of the arc tube 5 is WL, the preheating power Wf
Is preferably Wf <0.1 × WL.

On the other hand, assuming that the target temperature of the filament coil 31 is 800 ° C., there is a relationship shown in FIG. 7 between the approximate surface area S of the filament coil 31 and the preheating power Wf.
FIG. 7 shows an experimental result of the arc tube 5 using the stick coil 61. At this time, the rare gas G sealed in the bulb 21 of the arc tube 5 was argon, and the pressure of the rare gas G sealed in the bulb 21 was about 1000 Pa to 6000 Pa, but there was no change. Also, each tube 23a,
The inner diameters of 23b and 23c were changed from 5 mm to 15 mm, but there was no significant change. Therefore, by approximating the straight line shown in FIG. 7, Wf = 0.06 × S + 0.1. As a result, by setting S <1.7 × WL−1.7, the arc tube 5 can be further miniaturized, the amount of thermionic emission can be improved, and the preheating current (filament current) can be suppressed. 5 can improve the luminous efficiency. Furthermore, by securing the thermoelectrons in the dimmed lighting state at times, the loss of the emitter due to the sputtering of the filament electrode 22 is suppressed, and the lamp life of the arc tube 5 can be ensured. Here, for example, if the lamp power WL is 8 W, it is desirable to set the approximate surface area S to 12 mm ² .

Further, as an experiment, FD1 = 0.182
mm, FD2 = 0.0316mm, MD1 = 0.0500m
m, MD2 = 0.193mm, total length L2 of second coil
= 8.0 mm is approximately 9.3.
mm ² can be estimated.

Further, barium (Ba), strontium (Sr) and calcium
An electron-emitting substance composed of an oxide containing (Ca) is applied, and the triple coil 60 is attached to the luminous tube 5 consuming 8 W of power.
In the case of ² mm ² , the preheating power of the triple coil 60 could be reduced.

Next, a third embodiment will be described.

A filament electrode 22 sealed at both ends of a glass bulb 21 in which a fluorescent substance is coated on the inner surface and a small amount of mercury and argon gas are sealed at a pressure of 1500 Pa is an electrode mount. Electric power is supplied into the valve 21 through a lead wire made of nickel (Ni). A tungsten filament coil 31 is clamped to the inner lead of the filament electrode 22.

The filament coil 31 is a so-called triple coil 60 as a multiple coil. The filament coil 31 is coated with a discharge electrode emitter. This emitter is mainly composed of a carbonate such as an alkaline earth metal such as barium, strontium and calcium, and a sintered body containing an alkaline earth metal and a transition metal such as an oxynitride of barium and tantalum.

Here, the fired body may be an oxynitride containing at least one of barium, strontium, and calcium, and at least one of tantalum and niobium.

Then, 80% of this carbonate and oxynitride 2
0% is dispersed in an organic binder, and these carbonates and oxynitrides are mixed to form a slurry. Thereafter, the slurry is applied to the filament coil 31, and the filament coil 31 to which the slurry is applied is briefly and briefly applied for about 1 hour in a vacuum atmosphere.
The slurry is heated and heated to 200 ° C. to thermally decompose and activate the slurry.

Here, it is known that a carbonate of an alkaline soil metal is used as a main material, and the main material is activated in a vacuum atmosphere to generate an alkaline earth oxide, thereby lowering a cathode drop voltage. As a typical emitter of this kind, barium carbonate (BaCO ₃ ) is used in a vacuum atmosphere for a short time of 1200 minutes.
There is barium oxide (BaO) obtained by heating to about ° C.

When barium oxide is used as the emitter, the work function is low and the amount of emitted electrons is large.
Suitable as a cathode emitter, but generally mixed with strontium and calcium in addition to barium
An emitter of (Ba, Sr, Ca) O is used. In addition, this type of discharge electrode emitter has zirconium oxide
It is known that when an additive such as (ZrO ₂ ) is mixed, the life of the electrode is prolonged because the zirconium oxide is resistant to sputtering.

However, the emitter in which zirconium oxide is mixed has a lower electron emission capability than the case where zirconium oxide is not mixed.

Thus, barium, strontium and calcium carbonate and zirconium oxide are converted into 90%:
An emitter mixed in a proportion of 10% by weight;
Compare with an emitter mixed with zirconium oxide.

Ten arc tubes 5 each using both emitters were formed, and these 20 arc tubes 5 were continuously turned on by a constant current circuit having a lamp current of 300 mA and a frequency of 50 Hz. At this time, a lighting cycle in which the light was turned off for 30 minutes after lighting for 90 minutes was set.

As a result, comparing the lamp power of the two lamps after lighting for 100 hours with an average value of 10 lamps, the lamp power of the arc tube 5 using the emitter of this embodiment is about 13.
The power was 8 W, and the lamp power of the arc tube 5 using the emitter mixed with zirconium oxide was about 14.5 W.
Therefore, the arc tube using the emitter according to the present embodiment saves power.

Regarding the lamp life, each arc tube 5
The lighting time up to the point in time when lighting became impossible was measured, and assuming that the point in time when the quantity was reduced by half was the lamp life, the arc tube 5 using the emitter of the present embodiment and the emitter mixed with zirconium oxide were used. Each of the arc tubes 5 has about 7
500 hours.

As a result, carbonates of barium, strontium and calcium, and zirconium oxide (ZrO ₂ )
Is provided by the filament electrode 22 using an emitter in which a mixture of 90% and 10% by weight is used, even if the lamp current is reduced during the dimming operation, the electron of the arc tube 5 is reduced. The life of the filament electrode 22 of the bulb-type fluorescent lamp 1 capable of dimming and lighting can be extended without reducing the emission ability, so that the life of the lamp can be extended.

Next, FIG. 8 shows a fourth embodiment, and FIG. 8 is a graph showing the relationship between amalgam temperature and mercury vapor pressure.

The bulb 21 of the arc tube 5 contains 1 argon.
About 000 Pa is enclosed. A mercury amalgam containing mercury and at least indium is sealed in the valve 21 as a main amalgam 33. The main amalgam 33 has a composition ratio of indium to metal components other than mercury of 90% or more. The mass ratio of mercury to indium in the main amalgam 33 is:
6%. The mercury vapor pressure in the arc tube 5 is 600 Pa or more and 2000 Pa in a steady state when all light is turned on.
Below, and 200P in the steady state at the time of the dimming lower limit.
a or less.

The main amalgam 33 located in the arc tube 5 is in a liquid-solid mixed state A in a steady state when all light is turned on. That is, the liquid-solid mixing state A is a state near the maximum peak value shown in FIG. 8, that is, near the maximum value.

Here, the lamp current of the bulb-type fluorescent lamp 1 is usually set to about 200 mA to 300 mA at the time of all-light lighting and about several mA to several tens mA at the time of dimming according to the state of a dimmer not shown. Thus, the lighting circuit 6 is designed. As a result, the total luminous flux of the arc tube 5 changes, and light control becomes possible. However, in order to increase the dimming width, it is necessary to greatly change the lamp current. However, the design is very difficult, and the size of the lighting circuit 6 increases.
There are problems such as an increase in parts cost.

Therefore, the dimming width is increased by utilizing the difference between the mercury vapor pressures at the time of full light and at the time of dimming. Specifically, the mercury vapor pressure is 600 Pa or more and 2000 Pa at the time of all light.
The main amalgam 33 and the arc tube 5 are designed so that the maximum efficiency will be obtained below. Further, by utilizing the fact that the temperature of the arc tube 5 decreases during light control, the mercury vapor pressure is designed to be 200 Pa or less. As a result, even if the lamp current does not change significantly, the light output is greatly reduced, and a desired dimming width can be obtained.

Also, since the main amalgam 33 is in the liquid-solid mixed state A in the steady state at the time of all-light lighting, if the main amalgam 33 is in the liquid phase at the time of all-light lighting, the temperature is reduced by dimming. On the other hand, the liquid phase changes from the liquid state to the liquid-solid mixed state A, and further to the solid state, but due to the small change in the mercury vapor pressure in the liquid-solid mixed state A, The change in mercury vapor pressure with respect to the change in temperature is small.

Therefore, the lamp current is reduced and the arc tube 5
Since the mercury vapor pressure is maintained at a relatively high level even when the temperature decreases, it is necessary to greatly change the lamp current in order to obtain a desired dimming width.

As a result, when the main amalgam 33 in the steady state at the time of all-light lighting is in the liquid-solid mixed state A, it quickly shifts to the solid state when the temperature decreases, so that the mercury vapor with respect to the temperature change is changed. Since the change in pressure is large, even if the lamp current does not change significantly, the light output is greatly reduced, and a desired dimming width can be obtained.

Further, the main amalgam 33 contains mercury and at least indium, and the composition ratio of the metal component excluding mercury in the main amalgam 33 is such that indium is 90%
By the above, indium, bismuth, lead, generally used as a metal component of the main amalgam 33
It is tin and the like, and the mercury vapor pressure characteristic with respect to temperature greatly differs depending on the composition ratio. For this reason, in the case of the bulb-type fluorescent lamp 1, the arc tube temperature at the time of steady lighting is 100 ° C. to 1
Considering that the temperature is about 40 ° C., the steam configuration as the main amalgam 33 is optimal.

Then, when a lighting test was performed at an ambient temperature of 25 ° C., the lamp current was 250 mA and the total luminous flux was 1370 lm during all-light lighting. Also,
At the lower limit of dimming, the lamp current was 20 mA and the total luminous flux was 120 lm.

[0080]

According to the bulb-type fluorescent lamp of the first aspect, mercury amalgam is sealed in a bulb having an inner diameter of 5 mm to 10 mm, and a rare gas having a neon gas composition ratio of 80% or more is 240 Pa. ~ 2000Pa
And sealed with a pair of filament electrodes at both ends of the bulb.
When a lamp current of 50 mA flows between the filament electrodes and a lamp current of 2 mA to 10 mA flows between the filament electrodes at the lower limit of dimming, the lamp current means a discharge current flowing between the pair of filament electrodes. When the arc tube was lit at the time of lighting and at the lower limit of dimming under such conditions, it was confirmed by experiments that no striation occurred in this arc tube. This flicker of the arc tube can be prevented.

According to the bulb-type fluorescent lamp of the second aspect, in addition to the effect of the bulb-type fluorescent lamp of the first aspect, in addition to the effect of 240 Pa or more and 120 Pa or less in a bulb having a total length of 100 mm or less.
When the rare gas is sealed at a pressure of 0 Pa or less, the surface area of the filament electrode formed of an oxide obtained by applying an emitter to tungsten is S, and the power consumption of the arc tube is WL,
The filament electrode is sealed at both ends of the bulb so as to satisfy the relationship of 1.7 × WL−1.7, and the surface area S of the filament electrode is reduced by the area of the outer surface where the emitter and the filament are exposed when the emitter is applied. Then, experimentally, the amount of thermionic emission is improved, the luminous efficiency of the bulb can be increased by suppressing the preheating current (filament current), and sometimes by securing thermionics in the dimmed lighting state, This suppresses the disappearance of the emitter due to the sputtering of the filament electrode, so that the life of the arc tube can be prolonged, the size of the arc tube can be further reduced, and it is particularly effective at the time of lighting control.

According to the bulb-type fluorescent lamp of the third aspect, in addition to the effect of the bulb-type fluorescent lamp of the first or second aspect, a firing lamp containing a carbonate of an alkaline earth metal and an alkaline earth metal and a transition metal is provided. The filament electrode holds the mixture provided by mixing with the binder, and is thermally decomposed and activated in a vacuum atmosphere to form the filament electrode.
Since the fired body is an electron-emitting substance and has resistance to sputtering, the filament electrode of a bulb-type fluorescent lamp capable of dimming and lighting without reducing the electron emission ability even if the lamp current is reduced particularly during dimming and lighting. Life can be extended.

According to the bulb-type fluorescent lamp of the fourth aspect, in addition to the effect of the bulb-type fluorescent lamp of the third aspect, an oxidation containing at least one of barium, strontium and calcium and at least one of tantalum and niobium. If the sintered body is made of at least one of a material and an oxynitride, a filament electrode having a longer life without lowering the electron emission ability can be more easily implemented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a light bulb-shaped fluorescent lamp showing a first embodiment of the present invention.

FIG. 2 is a plan view showing an arc tube and a partition body of the bulb-type fluorescent lamp of the same.

FIG. 3 is a development view showing an arc tube of the bulb-type fluorescent lamp.

FIG. 4 is an explanatory diagram showing a case where a filament coil according to a second embodiment of the present invention is a double coil. (a) Illustration of completed double coil (b) Illustration of initial stage of manufacturing

FIG. 5 is an explanatory diagram showing a case where the filament coil is a triple coil. (a) Explanatory drawing of the completed triple coil (b) Explanatory drawing during manufacturing (c) Explanatory drawing of initial stage of manufacturing

FIG. 6 is an explanatory diagram showing a case where the filament coil is a stick coil. (a) Illustration of completed stick coil (b) Illustration of initial stage of manufacturing

FIG. 7 is a graph showing the relationship between the filament coil surface area and the preheating power.

FIG. 8 is a graph showing a relationship between amalgam temperature and mercury vapor pressure according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bulb-type fluorescent lamp 2 Cover 3 Cap 5 Arc tube 6 Lighting circuit 21 Bulb 22 Electrode 31 Filament coil 33 Main amalgam as mercury amalgam G Rare gas

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI theme coat ゛ (reference) F21Y 103: 025 F21S 5/00 EF term (reference) 3K014 AA04 DA05 5C015 PP02

Claims (4)

[Claims] 1. A valve having an inner diameter of 5 mm or more and 10 mm or less, a mercury amalgam sealed in the valve, a rare gas sealed in the valve at a pressure of 240 Pa to 2000 Pa, and a constituent ratio of neon gas is 80% or more. , And 100 mA to 250 m when lit and sealed at both ends of the bulb
A lamp current of 2 A to 10 m
An arc tube having a pair of filament electrodes through which the lamp current of A flows; a lighting circuit for lighting the arc tube;
A light bulb-type fluorescent lamp, comprising: a cover supporting a bulb of an arc tube and accommodating a lighting circuit; and a base attached to the cover. 2. The bulb has a total length of 100 mm or less, the rare gas is sealed in the bulb at a pressure of 240 Pa or more and 1200 Pa or less, and the filament electrode is formed of an oxide obtained by applying an emitter to tungsten. Let WL be the power consumption of
The bulb-type fluorescent lamp according to claim 1, wherein, when the surface area of the filament electrode is S, the relationship of S <1.7 × WL-1.7 is satisfied. 3. The filament electrode holds a mixture of a carbonate of an alkaline earth metal and a sintered body containing an alkaline earth metal and a transition metal, and is thermally decomposed and activated in a vacuum atmosphere. The bulb-type fluorescent lamp according to claim 1 or 2, wherein the bulb-shaped fluorescent lamp is formed. 4. The sintered body according to claim 3, wherein the sintered body is at least one of an oxide and an oxynitride containing at least one of barium, strontium and calcium, and at least one of tantalum and niobium. Light bulb shaped fluorescent lamp.