JPH113682A - Circular fluorescent lamp and luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circular fluorescent lamp with improved lamp characteristics by establishing optimum coolest parts and to provide luminaire using this circular fluorescent lamp capable of coping with profile lowering, in a circular fluorescent lamp using an annular glass tube bulb having a tube outer diameter of 14 to 18 mm. SOLUTION: This lamp L1 is equipped with an annular glass tube bulb 1 having an annulus outer diameter of 210 to 390 mm and a tube outer diameter of 14 to 18 mm having lead wires 4, 4 and exhaust pipes 6 on end parts sealing parts 2 of steam 3L, 3S, are formed, discharge electrodes 5 supported by the lead wires 4, 4, a phosphor coat 8 formed on the inner surface side of the glass tube bulb 1, and mercury and a rare gas sealed in the glass tube bulb 1. Coolest parts are so arranged as to be situated in tip regions of the exhaust pipes 6 projecting from the sealing parts 2 to the exterior of the bulb 1. A luminaire is to be mounted with the lamp 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ring-shaped fluorescent lamp in which a small-diameter glass tube bulb is bent in a ring shape, and a lighting fixture using the ring-shaped fluorescent lamp.

[0002]

2. Description of the Related Art A fluorescent lamp has a structure in which a fluorescent film is formed on the inner surface of a bulb made of a glass tube, and a rare gas such as mercury and argon gas is sealed in the bulb. Then, a discharge is generated in the bulb by a filament electrode or the like provided at the end of the bulb, and the discharge ionizes and excites the mercury vapor in the bulb to generate ultraviolet rays, which are converted into visible light by the phosphor coating. Visible light is emitted outside the bulb.

[0003] As for fluorescent lamps for general lighting used in homes and stores, those having a glass tube bulb having an outer diameter of about 29 mm are widely used, but they have been improved in light output and lamp lighting. Outer diameter of approx. 1 due to improved circuit
A fluorescent lamp using a bulb of 6 to 17 mm was developed,
The lighting fixture using the fluorescent lamp having a reduced diameter has advantages such as the possibility of thinning.

[0004]

Recently, there has been a demand for an improvement in the light emission characteristics such as a further increase in the efficiency of a fluorescent lamp in which the diameter of the glass tube bulb is reduced, and the present inventors have conducted various studies. . That is, in order to increase the output of a low-pressure mercury discharge lamp such as a fluorescent lamp, it is performed by increasing the lamp current. However, when the lamp current is increased, the tube wall temperature of the glass tube bulb also increases. In particular, when the diameter of the glass tube bulb is reduced as described above, this phenomenon remarkably appears.

Generally, in a low-pressure mercury discharge lamp such as a fluorescent lamp, the excitation of ultraviolet rays is affected by the vapor pressure of mercury sealed in a bulb, and the luminous efficiency is maximized at a tube wall temperature of about 40 ° C. Therefore, the light output tends to decrease whether it is higher or lower. It is not necessary to maintain the entire lamp at about 40 ° C., and since mercury is usually in a liquid state and its vapor pressure is controlled at the lowest temperature part (hereinafter, referred to as the coldest part) in the lamp, one lamp is used. About 4
It is sufficient that a coldest part at 0 ° C. is formed, and this coldest part is set in the middle part, end, or exhaust pipe of the valve.

[0006] The coldest part of the above-described lamp in which the glass tube bulb is reduced in diameter is an intermediate portion between the bulbs farthest from the two filament electrodes disposed opposite to each other, but because the bulb is reduced in diameter. Due to the above-mentioned operation, the tube wall temperature at the intermediate portion of the valve exceeds 40 ° C.

The present invention has been made in view of the above circumstances, and in a ring-shaped fluorescent lamp using a ring-shaped glass tube bulb having a tube outer diameter of 14 to 18 mm, the optimum coldest part is set to improve the lamp characteristics. It is an object of the present invention to provide a ring-shaped fluorescent lamp and a lighting fixture which can be made thin using the ring-shaped fluorescent lamp.

[0008]

DISCLOSURE OF THE INVENTION The annular fluorescent lamp of the present invention has been widely used in home lighting equipment and the like.
It is almost the same size as the W-type, 32W-type and 40W-type ring-shaped fluorescent lamps.
This is a ring-shaped fluorescent lamp such as a 39 W type or a 60 W type, which has been made smaller than expected, and has realized a thinner lighting device.

The outer diameter of the glass tube bulb is 14 to 18 m.
m. When bending the glass tube bulb, it is conceivable that the outside diameter of the tube is slightly reduced to partially deviate from the above range, but in the case of the present invention, it is sufficient that most of the outside is within the above range.

It is generally known that the efficiency of a fluorescent lamp is improved by reducing its tube diameter. Experiments have shown that in order to improve the lamp efficiency of the conventional annular fluorescent lamp by 10% or more, it is necessary to reduce the tube outer diameter to 65% or less. That is, the thickness is about 1
For a glass bulb of about mm, the outer diameter of the tube may be 18 mm or less. Further, it was visually confirmed that according to this size, the reduction in thickness of the ring-shaped fluorescent lamp was also sufficiently satisfied.

When the tube outer diameter is less than 14 mm, the lamp efficiency is numerically satisfactory, but the light emission characteristics equivalent to those of the conventional ring-shaped fluorescent lamp cannot be obtained.
Moreover, it becomes extremely difficult to bend or bend the glass tube bulb in a ring shape.

The ring diameter of the glass tube bulb is preferably within ± 5% of the conventional ring outer diameter. If it corresponds to a 30W type, the outer ring diameter is 210 to 235 mm, 32
If it corresponds to W type, the ring outer diameter is 285-310m
m, 40W type, the outer ring diameter is 365-65
390mm, the outer ring diameter of 24W type is 210-235mm,
The outer ring diameter of the 39W type is 285 to 310 mm, and the outer ring diameter of the 60W type is within the range of 365 to 390 mm.

The reason why this range is desirable is that, by reducing the tube outer diameter so as to approximate the conventional ring outer diameter, the lamp can be made thinner while maintaining the image of the size of the conventional ring-shaped fluorescent lamp. If the outer diameter of the tube is approximated, the discharge path length can be increased even if the outer diameter of the tube is small. The shape of the ring-shaped fluorescent lamp may be a polygon such as a perfect circle, an oval, or a square, and the outer diameter may be measured by an average value of the short diameter portion and the long diameter portion or by passing over.

If the outer ring diameter exceeds 390 mm, the discharge path length becomes too large, and the starting voltage must be significantly higher than in the prior art. Is less feasible as a ring-shaped fluorescent lamp.

The ring-shaped fluorescent lamp according to the first aspect of the present invention has a ring outer diameter of 210 to 390 mm and a tube outer diameter of 14 to which a sealing portion with a stem having a lead wire and an exhaust pipe is formed at an end. A glass tube bulb of about 18 mm, a discharge electrode supported by a lead wire, a phosphor film formed on the inner surface side of the glass tube bulb, and mercury and a rare gas sealed in the glass tube bulb. In addition, a coolest part is provided at the end of the exhaust pipe protruding outside the valve from the sealing part.

In a lamp in which a bulb is formed by reducing the diameter of a glass tube, as a result of controlling the vapor pressure of mercury in the exhaust pipe portion, the adhesion of mercury to the bulb and the phosphor film can be reduced. It is sufficient that the coldest part is 1% or less of the total surface area in the valve, so that it is sufficient in the exhaust pipe.
In addition, since the exhaust pipe portion is housed in the base and protected, an unexpected situation such as breakage can be avoided.

The glass tube forming the bulb is made of soft glass such as soda lime glass or lead glass, but may be made of hard glass such as borosilicate glass or quartz glass. The thickness of the valve is 0.8-1.
It is preferably about 3 mm, but is not limited to this. The rare gas sealed in the valve contains argon, neon, krypton, nitrogen, or the like.

As the stem, a flare stem, a button stem or a bead stem (in this case, the sealing portion is a pinch seal) can be used.

As the pair of discharge electrodes, a hot cathode type electrode in which an emitter material is applied to a coiled filament can be applied, but other types of electrodes may be used. When it is necessary to light the lamp with high output, it is preferable to use a triple coil for the hot cathode type electrode.

Further, as the form of mercury sealed in the bulb, liquid mercury, amalgam or GEMEDIS (trade name) in which a mercury alloy is formed on a plate-like body can be used.

Further, what is referred to as an exhaust pipe in the present specification does not refer to an exhaust pipe which communicates with the inside and outside of a valve and is used for sealing an exhaust or a discharge medium during an exhaust operation. Also, it includes a member used as a holding member at the time of an electrode assembling operation or a sealing operation or as a coldest portion as in the present invention, and is called a thin tube.

The ring-shaped fluorescent lamp according to the second aspect of the present invention has a ring outer diameter of 21 at both ends formed with sealing portions to the stem.
An annular glass tube bulb having a tube outer diameter of 0 to 390 mm and a tube outer diameter of 14 to 18 mm, a lead wire provided on at least one of the stems, and an exhaust pipe having a tip portion protruding outward from a sealing portion; And a discharge electrode positioned within a range of 30 to 50 mm from the sealing portion at the bulb end, a phosphor coating formed on the inner surface side of the glass bulb, and sealed in the glass bulb. And mercury and a rare gas.

In the lamp in which the bulb is formed by reducing the diameter of the glass tube, the distal end portion of the exhaust pipe away from the discharge electrode is configured as the coldest part, and the same effect as in the first aspect is achieved. Further, if the separation distance is less than 30 mm, the function of the coldest part is not exerted due to the influence of the heat of the electrode part. Further, if the separation distance exceeds 50 mm, the electrode portion comes close to or comes into contact with the curved bulb wall, causing damage to the phosphor coating, discoloration due to heat, etc., and also produces a dark area at the bulb end. .

According to a third aspect of the present invention, there is provided the annular fluorescent lamp, wherein a portion near an end of the annular glass tube bulb is bent in a direction perpendicular to the plane with the annular section as a plane. Is connected, and the stem is provided orthogonal to the annular portion surface of the glass tube bulb.

The same effect as described in the first and second aspects is also obtained in a lamp connected to a bent portion or a branch pipe in which the vicinity of both ends of the bulb is bent in the same direction. Further, if the discharge electrode does not reach the annular portion of the bulb and is located in the bent portion or the branch pipe, blackening does not occur on the bulb wall near the electrode, and the light emitting region can be enlarged.

A ring-shaped fluorescent lamp according to a fourth aspect of the present invention is characterized in that the height of the glass tube from the sealing portion of the stem having the exhaust pipe is 20 to 40 mm.

According to the second aspect of the present invention, the same operation as described above is achieved.

If the height of the glass tube is less than 20 mm, the mount height becomes low, and the effect of the heat of the electrode portion does not act as the coldest portion. On the other hand, if it exceeds 40 mm, the mount height becomes high, and the electrode portion approaches or comes into contact with the curved bulb wall, which may damage the phosphor coating or cause discoloration due to heat.

The ring-shaped fluorescent lamp according to claim 5 of the present invention is characterized in that the lamp current is 300 to 600 mA.

If the lamp current is less than 300 mA, the temperature of the coldest part becomes 40 ° C. or less, which is the optimum temperature, and the luminous efficiency is significantly reduced. On the other hand, if it exceeds 600 mA, the temperature of the coldest part greatly exceeds 40 ° C., which is the optimum temperature, and the luminous efficiency is reduced.

According to a sixth aspect of the present invention, there is provided an illuminating device for supplying electric power to the luminous device, the ring-shaped fluorescent lamp according to any one of the first to fifth aspects, and the ring-shaped fluorescent lamp. And a high-frequency lighting circuit.

Since the ring-shaped fluorescent lamp in which the diameter of the glass tube bulb is reduced is used, the height of the apparatus can be reduced.

The apparatus body is a ceiling-mounted type, a ceiling-hanging type, or a wall-mounted type, and a glove, a shade, a reflective shaver, or the like may be mounted thereon, a ring-shaped fluorescent lamp is exposed, or a light control plate. May be provided.

By the way, the lighting equipment is not limited to the one in which one ring-shaped fluorescent lamp is attached to the lighting equipment body. For example, a plurality of ring-shaped fluorescent lamps having different lamp powers are concentrically provided on the lighting equipment on the same plane or in height. You may attach so that it may be changed and arrange | positioned.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a ring-shaped fluorescent lamp according to the present invention will be described with reference to FIGS. FIG.
Is a plan view of a ring-shaped fluorescent lamp L1 having a rated lamp power of 60 W, for example. FIG. 2 is a cross-sectional plan view showing a main part of the lamp L1 of FIG. 1 (near an end of a glass tube bulb), and FIG.
FIG. 2 is a partial cross-sectional front view showing a lighting fixture D for lighting the annular fluorescent lamp L1 of FIG.

In the drawing, reference numeral 1 is a conceptual diagram schematically showing a ring-shaped bulb made of a soda-lime glass tube, and its dimensional relationship is slightly different from the actual one. This valve 1 has an outer diameter Bd of about 1
6.5 mm, wall thickness is about 1.1 mm, ring-shaped outer diameter (crossover) is about 373 mm, and inner diameter (crossover) is about 340 mm.

Reference numerals 3L and 3S denote flare stems having an outer diameter Sd of about 8 mm and a thickness of about 1.0 mm at an intermediate portion excluding a lead glass tube sealed portion sealed at the end of the bulb 1. A sealing portion 2 is formed at the fusion portion between the two. This stem 3
L and 3S have a pair of lead wires 4 and 4 and an exhaust pipe 6 made of a lead glass tube having an outer diameter of about 5.5 mm and a wall thickness of about 0.9 mm.
The exhaust pipe 6 is connected from the sealing portion 2 to the valve 1.
It is sealed at a place protruding about 5 to 10 mm outside. A discharge electrode 5 composed of a coiled filament is connected between the ends of the lead wires 4, 4.
Is led out of the valve 1.

The stems 3L and 3S sealed to the end of the valve 1 have different heights. That is, for example, in FIG. 2, the right stem 3L is the height Sh of the stem tube 31 (the height from the sealing portion to the top of the stem tube 31).
Is about 27 mm, and the mount height Mh (height from the sealing portion to the discharge electrode 5 composed of a coiled filament) is about 37 mm. The stem 3S on the left side of the figure has a height Sh of the stem tube 31 of about 13 mm and a mount height Mh of about 22 mm, and the stem 3S is of the same size as a conventional product.

On the inner surface of the bulb 1, a protective film 7 made of, for example, alumina (Al ₂ O ₃ ) fine particles and a phosphor film made of a three-wavelength rare earth phosphor or a continuous-wavelength halophosphate phosphor are used. In this bulb 1, mercury and a rare gas such as argon Ar, krypton Kr, xenon Xe or the like are used alone or as a mixture in a discharge maintaining medium. In this case, Ar75Vol% -Ne25V
ol% is sealed at about 4.5 Torr.

A base 9 is attached between the sealing portions 3 at both ends of the bulb 1 in a bridging manner. The base 9 has four terminal pins 91 electrically connected to the electrodes.
The valve 1 is provided so as to be inclined toward the center of the valve 1. The four terminal pins 91,... Have a vertical and horizontal pin spacing of about 6 mm and about 10 mm, differing from the standardized pin spacing of the base, and a conventional socket is mounted on the base 9. Erroneous insertion can be prevented.

FIG. 3 shows an embodiment of the lighting equipment D of the present invention. In the drawing, D1 is a housing which forms a thin or round light-emitting equipment body having a circular or square shape. A high-frequency lighting circuit D2 comprising a power supply connection mechanism, an inverter lighting circuit, and the like, and a ring-shaped fluorescent lamp L1 supported by lamp holders D3 and D3 are mounted below the main body D1. I have. D4 is a socket connected to the terminal pins 91 of the lamp L1,.
Is a light control body composed of a light diffusion plate or the like attached to the opening of the main body D1.

The annular fluorescent lamp L1 is mounted on and supported by the lamp holders D3 and D3 of the luminaire D, and the socket D4 is inserted and connected to the terminal pins 91,... Through a power supply connection mechanism and a high frequency lighting circuit D2. Power and light.

The ring-shaped fluorescent lamp L1 continues to emit light due to the discharge between the discharge electrodes 5 and 5, and its temperature rises due to discharge heat. It is the discharge electrode 5 composed of a coiled filament that is heated most by this lighting.
Further, the portion where the temperature rise is lowest, that is, the coolest portion is not the central portion of the bulb 1 away from the discharge electrodes 5 and 5, but
The exhaust pipe 6 of the stems 3L and 3S, and the right stem in which the height Sh of the stem pipe 31 which is not the exhaust pipe 6 on the left stem 3S side in FIG. 2 is large and the separation distance from the discharge electrode 5 is long. It is formed at the distal end 61 of the exhaust pipe 6 on the 3L side.

In the ring-shaped fluorescent lamp L1, even if the diameter of the glass tube of the bulb 1 is reduced so that the temperature of the wall of the bulb 1 rises, it is not at the center of the bulb 1 but exhausted regardless of the bulb 1 diameter. Since the coolest part is formed at the tip part 61 of the tube 6, the mercury vapor pressure is controlled without any trouble. As a result, even if the lighting is continued, the light output does not decrease and the luminous efficiency can be improved. it can.

According to the experiments conducted by the present inventors, the outer diameter Bd of the glass tube bulb 1 was 14 to 18 mm (the wall thickness was 0.8 to 0.8 mm).
In the ring-shaped fluorescent lamp L1 having a reduced diameter of 1.3 mm), the mount height Mh (the height from the sealing portion to the discharge electrode 5 composed of a coiled filament) is 30 to 50 m.
m, the height Sh of the stem tube 31 (from the sealing portion to the stem tube 31)
Height to the top of the. ) Was set to 20 to 40 mm, it could be confirmed that the above-described effect was exhibited.

If the mount height Mh is less than 30 mm, the heat of the electrode portion affects the tip portion 61 of the exhaust pipe 6 and does not function as the coolest portion. In addition, if it exceeds 50 mm, the electrode portion approaches or abuts against the curved wall of the bulb 1 to damage the phosphor coating or generate discoloration by heat. A dark portion was formed at the end, which was not preferable. Depending on the type, a good result was obtained at about 35 to 45 mm.

The height Sh of the stem tube 31 is related to the above-mentioned mount height Mh. If the height Sh is less than 20 mm, the mount height Mh becomes low, and the effect of the heat of the electrode part affects the function as the coldest part. I don't play. On the other hand, if it exceeds 40 mm, the mount height Mh becomes high, and the electrode portion comes close to or comes into contact with the curved bulb wall, causing problems such as damage to the phosphor coating and discoloration due to heat, which is not preferable. .

Table 1 shows various characteristics of the annular fluorescent lamp 1L used in this experiment. The lamp was tested under the same conditions except for the height Sh of the stem tube 31 and the mount height Mh. The ring-shaped fluorescent lamp 1L was vertically lit at a lighting frequency of 45 kHz, and electrical characteristics, total luminous flux, and temperature were measured.
The total luminous flux indicates an initial luminous flux after a lapse of time sufficient for mercury to collect in the coolest part when 100 hours have elapsed from the start of lamp lighting.

[0049]

[Table 1] As is clear from Table 1, the lamp L1 having the increased mount height Mh (the height Sh of the stem tube 31) had an optimum mercury vapor pressure, and a remarkable improvement in each characteristic was recognized.

FIGS. 4 to 7 show the second and third embodiments of the annular fluorescent lamp L2 of the present invention, in which the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals. The description is omitted. 4 is a plan view of the ring-shaped fluorescent lamp L2, FIG. 5 is a front view of the lamp L2 shown in FIG. 4, and FIG.
7 is an explanatory diagram showing an enlarged main part (near the end of the glass tube bulb), and FIG. 7 is an explanatory diagram showing an enlarged main part (near the end of the glass tube bulb) of the annular fluorescent lamp L3.

The annular fluorescent lamp L2 shown in FIGS.
Is formed such that a bent portion 11 is formed adjacent to both ends of an annularly bent glass tube bulb 1 in a direction perpendicular to this plane with the annular portion as a plane. The stems 3L and 3S sealed at right angles to the annular surface of the glass tube bulb 1. And these two sealing parts 2, 2
And a synthetic resin base 9 covering the bent portions 11, 11.
Is crowned. Further, four terminal pins 91 are provided on the top side of the base 9. In the figure, 95 is
A buffer made of a silicone adhesive or the like for preventing and fixing the bent portions 11 and 11 to each other directly. Further, the bent portions 11 and 11 may be welded to each other by glass tubes.

The annular fluorescent lamp L3 shown in FIG. 7 is adjacent to both ends of a glass tube bulb 1 which is bent in an annular shape and has an annular portion as a plane and is adjacent to the bulb 1 in a direction perpendicular to this plane. The branch tube 12 made of a separate glass tube is connected in an airtight manner, and the other parts are the same as the above-mentioned annular fluorescent lamp L2.

The ring-shaped fluorescent lamps L2 and L3
Is connected to a socket of a lighting fixture (not shown) and is turned on, but has the same operation and effect as the lamp L1 of the above-described first embodiment. If the lower surface of the base 9 is formed of a transparent member, there is an advantage that light emission from the bulb 1 located in the base 9 can be effectively used.

The present invention is not limited to the above embodiment. For example, the height S of the stem tube of a pair of stems
h and the mount height Mh, one of which is the same as the size of the conventional product and the other is made different from the size of the conventional product. The coldest part for controlling the mercury vapor pressure is provided at both ends of the valve.

In a fluorescent lamp or the like, one of a pair of stems is provided with no exhaust pipe or the exhaust pipe is closed even with the exhaust pipe. May be in the form of the present invention. The exhaust pipe referred to in the present invention is not limited to a pipe used as an exhaust passage for filling an exhaust gas or a discharge medium in a valve, and includes and refers to a thin pipe used as a coldest part shown in the present invention regardless of exhaust. is there. That is, it is sufficient that the coolest part is formed after the lamp is completed, and it is not limited whether or not the exhaust pipe of the present invention is used at the time of exhaust work. As an auxiliary means for cooling the exhaust pipe tip projecting into the base, a vent hole may be formed in the base or the exhaust pipe tip and the base may be connected by a heat conductor.

Further, the lighting equipment is not limited to the above embodiment, and can be applied to various lighting equipment.

[0057]

According to the first to fifth aspects of the present invention, even when the diameter of the glass tube bulb is reduced and the temperature of the bulb rises, the exhaust pipe section which is not related to the bulb is essential. And a ring-shaped fluorescent lamp whose luminous efficiency can be improved with a simple configuration having the coldest part. Further, by reducing the bulb diameter, the size of the lamp can be reduced, and it is possible to reduce the size of the lighting fixture to which this lamp is mounted and turned on.

[Brief description of the drawings]

FIG. 1 is a plan view showing a ring-shaped fluorescent lamp according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional front view showing a main part (near an end of a glass bulb) of the fluorescent lamp of FIG.

FIG. 3 is a cross-sectional front view showing an embodiment of a lighting device for lighting the ring-shaped fluorescent lamp of FIG. 1;

FIG. 4 is a plan view showing a second embodiment of the ring-shaped fluorescent lamp.

FIG. 5 is a front view of the fluorescent lamp shown in FIG.

FIG. 6 is a cross-sectional front view showing a main part (near an end of a glass tube bulb) of the fluorescent lamp of FIG.

FIG. 7 is a cross-sectional front view showing a main part (near an end of a glass tube bulb) of a ring-shaped fluorescent lamp according to a third embodiment.

[Explanation of symbols]

 L1, L2, L3: annular fluorescent lamp 1: glass tube bulb 11: bent portion 12: branch tube 2: sealing portion 3L, 3S: stem Sh: height of stem tube Mh: mount height 4: lead wire 5: Discharge electrode (coil filament) 6: exhaust pipe 9: base D: lighting equipment D1: lighting equipment main body D2: high frequency lighting circuit

Claims (6)

[Claims] 1. An outer diameter of a ring having a sealing portion with a stem having a lead wire and an exhaust pipe at an end portion is 210 to 390 m.
m, an annular glass tube bulb having an outer diameter of 14 to 18 mm; a discharge electrode supported by a lead wire; a phosphor coating formed on the inner surface side of the glass tube bulb; A ring-shaped fluorescent lamp comprising: mercury and a rare gas; and a coldest portion at the end of the exhaust pipe protruding outside the bulb from the sealing portion. 2. An annular glass tube bulb having a ring outer diameter of 210 to 390 mm and a tube outer diameter of 14 to 18 mm having a sealing portion with a stem at both ends; a lead wire provided on at least one of the stems. And an exhaust pipe protruding outward from the sealing portion at the tip end thereof; a discharge electrode supported by the lead wire and located within a range of 30 to 50 mm from the sealing portion at the bulb end; A ring-type fluorescent lamp comprising: a phosphor coating formed on an inner surface side of a bulb; and mercury and a rare gas sealed in a glass tube bulb. 3. A bent portion or a branch pipe in which the vicinity of the end of the annular glass tube bulb is bent in a direction perpendicular to the plane with the annular portion as a plane is connected to the surface of the annular portion of the glass tube bulb. 3. The ring-shaped fluorescent lamp according to claim 1, wherein the stem is provided at right angles to the stem. 4. The annular fluorescent lamp according to claim 1, wherein the height of the glass tube from the sealing portion of the stem having the exhaust pipe is 20 to 40 mm. 5. The ring-shaped fluorescent lamp according to claim 1, wherein the lamp current is 300 to 600 mA. 6. An apparatus main body; a ring-shaped fluorescent lamp according to any one of claims 1 to 5 disposed on the apparatus main body; and a high-frequency lighting circuit for supplying power to the ring-shaped fluorescent lamp. Lighting equipment characterized by the above-mentioned.