JPS58103758A - Low-pressure vapor electric-discharge lamp - Google Patents

Abstract

PURPOSE:To obtain a compact single-base incandescent-lamp-type fluorescent lamp, which can be easily made and which has a high efficiency and a small luminance nonuniformity, by curving at least one of inner tubes into an almost U shape so as to make the length of the inner tube larger than that of the outer tube. CONSTITUTION:Since an electric-discharge lamp is constituted by folding a positive column four times its entire length is about one fourth of that of the conventional straight electric-discharge lamp. Therefore, the lamp can be remarkably easily handled, and has an excellent appearance. When this electric-discharge lamp is compared with the conventional electric-discharge lamp while maintaining their output luminious flux constant, since the surface area of this lamp is smaller than that of the conventional one, the luminance of this lamp becomes higher than that of the conventional one, and this lamp is used as a high luminance lamp to a larger extent. In addition, in the lamp, visible light discharge from the open end of an inner tube 103 in the axial direction, after once passing through an outer tube stem 102, returns back by being reflected by a visible-light reflecting layer provided near the stem 102. As a result, the extreme luminance nonuniformity caused on the surface of an outer tube is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in low-pressure steam discharge lamps, and more particularly to a single-cap bulb-shaped fluorescent lamp having a substantially spherical or cylindrical outer shape.

Conventional fluorescent discharge lamps for lighting generally have a structure in which electrodes are installed at both ends of a long, thin glass tube, but such long discharge lamps are inconvenient to handle, and they are short, small, and bright. The development of a discharge lamp for lighting was desired.

One method for this purpose, as seen in Japanese Utility Model Application Publication No. 56-82807, is to bend a tubular bulb with electrodes at both ends into a U-shape at its center, and further extend both ends of the tube into a U-shape. Some bulbs are equipped with a curved tube-shaped valve that is curved in a U-shape in a direction perpendicular to the plane. Figure 1 shows an example of this, in which 1 is a base, 2 is a cap, 4 is a globe, 10 is a curved valve, 1
3 is a stabilizer. However, the discharge lamp produced using this method is
It has drawbacks such as difficulty in manufacturing the bent tube-shaped pulp, and a decrease in luminous efficiency because the temperature of the bent tube-shaped pulp becomes higher than the optimum value from the viewpoint of emissivity.

Furthermore, as another method for realizing a compact discharge lamp, as shown in British Patent No. 619,721, a plurality of single-ended straight tubes are provided inside the outer bulb, and the discharge path is formed into a U-shape. There is something I did. FIG. 2 shows an example of this. In the figure, 21 is an outer tube valve, 22.23 is a straight pipe with a single opening, 24.25 is a cathode, 26 is a starter switch, 2
7.28 is a ballast, 29.30 is an AC power supply terminal, and 31 is a discharge path.

However, the discharge lamp produced using this method has the disadvantage of glazing. One is that the structure shown in Figure 2 has a structure in which the solar column is bent only once, so its total length is at most half that of a conventional linear discharge lamp. In fact, the total length of the discharge lamp in the embodiment described in this patent specification is approximately 30 crn, which is still insufficiently short and is still inconvenient to handle. Furthermore, in the discharge lamp with the structure shown in FIG. 2, a part of the positive column extends outside the single-ended open-hole straight tubes 22 and 23, so the ultraviolet rays emitted in this part cannot excite the phosphor. This results in a loss of power.

If the top of the outer bulb 21 is coated with a phosphor, this loss will be reduced, but since the phosphor is coated only on a portion of the bulb,
Appearance becomes noticeably worse. If the entire structure is coated with phosphor, the appearance will be improved, but a portion of the visible light emitted from the straight pipes 22 and 23 with single-ended openings will be absorbed by the phosphor, resulting in increased power loss.

Furthermore, the discharge lamp with the structure shown in FIG.
．． Since a considerable portion of the visible light generated within the discharge lamp 23 exits through each open end, when the discharge lamp is viewed from the top, the end face of the single-ended straight tube is visible, which is extremely bright. For this reason, the luminance unevenness on the surface of the discharge lamp is large, and the light distribution is also poor.

Accordingly, an object of the present invention is to provide a compact, highly efficient,
To provide a single-cap light bulb type fluorescent discharge lamp which has little unevenness in brightness and is easy to manufacture.

In order to achieve the above object, the present invention provides one or more inner tubes, one end of which is sealed and the other end of which is open, inside a translucent outer tube that forms an airtight space inside. , a discharge electrode is provided near the sealed end in the inner tube, and at least one of the inner tubes is bent into a substantially U-shape so that the length of the inner tube is larger than the length of the outer tube, and It is characterized in that the open end of the inner tube is located near the stem sealed end of the outer tube.

Further objects, characteristic configurations, and effects of the present invention will be made clear in the detailed description given below with reference to Examples.

Hereinafter, the present invention will be explained in detail based on examples.

FIG. 3 is a diagram showing an embodiment of the present invention.
102 is a translucent outer tube, and 102 is an outer stem that forms an airtight space integrally with the outer tube, and low-pressure metal vapor or rare gas is sealed in the airtight space through the entire exhaust pipe 108.

Reference numeral 103 denotes a roughly U-shaped inner tube, and a luminescent material 104 such as a phosphor is provided on the inner wall of the tube. Inner pipe 103
One end is open while the other end is substantially or completely sealed, and in the vicinity of the sealed end there is provided an oxide cathode 105, for example, which operates on direct current or alternating current.

The lead wire 106 of the electrode passes through the sealed end of the inner tube 103 and the outer tube stem 102, and is exposed to the outside of the discharge lamp. It is also possible to apply a coating to the electrode lead wire. The walking path in the discharge lamp shown in FIG.
It connects the space. Most of the discharge path is made up of positive pillars.

The phosphor 104 is excited by the ultraviolet rays generated by the positive column and generates visible light.

As a specific example, the outer tube 101 is made of soft glass with a diameter of 704 mm and a length of 115 mm, the outer tube stem 102 is made of soft glass with a diameter of 70+++ m in the shape of a button stem or flare stem, and the inner tube 103 is made of soft glass with a diameter of 12 to 20 m. , a soft glass with a length of 200 m, the luminescent material 104 is a phosphor that emits ultraviolet light of 253.7 nm, the electrode 105 is a directly heated cathode having an alkaline earth oxide film, the electrode lead 106 is Dumet, N:, It is a metal such as Fe, /Ni, etc., and several Torr of rare scum such as Hg, Ne, Ar, Kr, and Xe is sealed in the airtight space. The technique of bending a soft crow having a diameter of about 15 to 20 mm into a U-shape is well known, and there is no particular difficulty in bending it only - times in this way. However, the above content is an example, and the present invention is not limited thereto. Note that Figure 4 is a front view of Figure 3, and Figure 5 is a front view of Figure 3.
FIG.

In FIG. 3, the outer tube 101 may be transparent.

The surface may be frosted glass-like, or a light-diffusing substance may be attached to the surface to diffuse light. In this way, the inside of the discharge lamp becomes invisible and at the same time, the luminance distribution on one surface becomes more uniform.

There is an optimum value for the mercury pressure in a low-pressure mercury discharge lamp. Since this mercury pressure becomes a vapor pressure corresponding to the temperature of the coldest part within the discharge lamp, it is important to maintain the temperature of the coldest part within the discharge lamp at an appropriate value. For example, the mercury vapor pressure in the discharge lamp shown in FIG. 1 is determined by the temperature inside the cooling section of the curved bulb 100. However, since the curved tube-shaped bulb IO is surrounded by the pace 1 and the globe 4, the temperature k of the curved tube-shaped pulp 10 rises too much, the mercury vapor pressure increases, and the luminous efficiency decreases.

However, according to the structure shown in FIG. 3 of the present invention, the mercury vapor pressure is determined by the inner surface temperature of the coldest part of the outer tube 101. Since the outer tube is in direct contact with the outside air, its temperature is lower than that of the curved tube valve in FIG. 1, and the mercury vapor pressure is close to the optimum value p.

Therefore, the luminous efficiency is also higher than that of the discharge lamp having the structure shown in FIG.

Furthermore, the discharge lamp with the structure shown in Fig. m3 has a -fc structure in which the positive column is bent four times, so the overall length is easy and the appearance is excellent. Comparing this discharge lamp with the discharge lamp with the structure shown in Figure 2, if the output light of the two is constant, the former has a smaller narrow area, so the brightness is correspondingly higher, and it has a wider range of applications as a high-intensity lamp. increase

Furthermore, in the discharge lamp with the structure shown in FIG. Because it is reflected back by a light reflecting layer (not shown),
Significant brightness unevenness on the outer tube surface is reduced.

According to the structure shown in FIG. 3, the inner tube 103 is U-shaped, but it is not very difficult to bend the glass tube with a diameter of about 15 tw only once. The phosphor can be applied to the inner wall surface of the inner tube either before or after bending. Although it is still necessary to provide a phosphor on the inner wall of the curved bulb 10 of FIG. 1, it is extremely difficult to provide the phosphor after the bulb has been bent twice.

On the other hand, if a phosphor is provided before the bulb is bent, a binder is used to prevent the phosphor from deteriorating due to temperature rise during the heating process necessary for bending the bulb, and from peeling off the phosphor film during the bending process. As a result, the luminous efficiency of the phosphor is significantly reduced. The curved pipe valve in Figure 1 has three bends, while the inner pipe in Figure 3 has only two bends, so the latter is more prone to deterioration as described above. Less is. Furthermore, as described above, in the structure shown in FIG. 3, it is possible to apply the phosphor after bending the tube, so that there is no reduction in the amount of phosphor emission remaining due to the bending of the tube.

FIG. 6 shows another embodiment according to the present invention, in which 111
is a phosphor film provided on the inner surface of the outer tube stem 102. A part of the positive column comes out of the inner tube 103 (11), but the ultraviolet rays generated by this part of the positive column are absorbed by the phosphor 1.
11, and the luminous efficiency of the discharge lamp increases. Moreover, since this portion is the inner surface of the outer tube stem 102, the appearance will not be deteriorated.

The portion of the fluorescent film 111 in FIG. 6 is replaced with a Tie instead of a fluorescent material.
, or an At vapor-deposited film. Inner tube 10
The light emitted from the film 111 is reflected by the film 111 and used effectively. Of course, the fluorescent material or the reflective film 111 may be provided on the entire inner surface of the outer tube stem.

FIG. 7 shows still another embodiment according to the present invention, in which the edge connecting the two electrodes 105 passes over the center of the outer tube stem 102. In this way, the electrode lead wire 106 is connected to the outer tube stem 102.
Since the tube passes through a symmetrical position inside, it has the advantage of making it easier to create the outer tube stem.

FIG. 8 shows yet another embodiment according to the invention, in which the open end 112 of the inner tube 103 is widened.

By doing so, mercury can easily flow into the inner tube 103 from outside the inner tube 103, and a phenomenon in which mercury vapor is insufficient in the inner tube 103 can be prevented.

FIG. 9 shows yet another embodiment of the invention in which the open end 113 of the inner tube 103 is narrow.

By doing so, it is possible to prevent visible light generated within the inner tube 103 from escaping to the outside of the outer tube stem 102 from the open end.

FIG. 10 shows still another embodiment of the VC of the present invention,
An auxiliary inner tube 114 is provided at the joint between the two inner tubes 103, and a luminescent material 104 is provided on the inner wall of the auxiliary inner tube. By doing so, it becomes possible to effectively use almost all of the ultraviolet light in the column of light generated by the discharge.

Figure M11 shows yet another embodiment according to the present invention;
An auxiliary electrode 115 is provided near the open end of the inner tube 103 of the book. 116 is the lead wire. When lighting the discharge lamp shown in Fig. 11, for example, first, one inner tube 1
If discharge is started between electrode 105 and auxiliary electrode 115 in both inner tubes 103 and then discharge is started between electrodes 105 and 105' in both inner tubes 103, the voltage required to start discharge is (13) Significantly lower than when 115 is not used.

Furthermore, according to the structure shown in FIG.
Only one of them or both can be made to emit light at the same time, that is, the luminous flux of the discharge lamp can be adjusted in two stages.

FIG. 12 shows still another embodiment according to the present invention, in which an outer tube 101 and an outer tube stem 102 have a
Additionally, a plurality of automatically activated ignition devices 117, such as starter starters, are provided. This results in
The number of electrode lead wires passing through the outer tube stem 102 can be reduced, and connection with the discharge lamp drive circuit can be facilitated.

FIG. 13 shows yet another embodiment of the present invention, in which each inner tube 103 is formed not by bending a glass tube but by connecting a plurality of glass tubes end to end.

FIG. 14 shows yet another embodiment of the present invention, in which the two inner tubes 103 in FIG. 3 are partially connected at their open ends on the main flow side. 14) Therefore, the inner tube 119 according to this embodiment has an integral structure, resulting in a reduction in the number of parts and an increase in mechanical strength. The inner tube 119 has one or more inner tube holes 12.
0 is provided to connect the inside and outside of the inner tube 119. Since the inner tube hole 120 is provided, the inner tube 11
9 The mercury vapor pressures inside and outside are equal. Therefore, even if the inner tube 119 is heated by electric discharge, the vapor pressure inside the inner tube will increase as the inner tube is heated, and the efficiency will not decrease.
Since it is determined by the temperature of the coldest part of 02, it is possible to prevent a decrease in efficiency.

FIG. 15 shows yet another embodiment of the present invention, in which indium, etc., is placed inside the inner tube 103 and near the electrode 105.
A metal 121 forming a mercury amalgam is provided. In the early stages of lighting the discharge lamp, the mercury vapor pressure within the inner tube 103 may be insufficient, and not only may a sufficient luminous flux not be obtained, but the discharge starting voltage may also become high.

However, when the mercury amalgam 121 is provided near the electrode 105, the electrode 105 emits the generated (15). As a result, sufficient mercury vapor pressure can be maintained even in the initial stage of lighting.

FIG. 16 shows yet another embodiment of the present invention, in which the inner tube 103 is roughly U-shaped, but the Iffj mouth end side is short. By adopting the above-mentioned shape, the tube voltage becomes low, and the cultivation of the inner tube 103 becomes easier.

FIG. 17 shows yet another embodiment according to the present invention, in which the inner tube 103 is roughly U-shaped but rounded overall. By adopting the above shape, the υ discharge length becomes longer, which improves efficiency and further improves the appearance.

Furthermore, by making the outer tube 101 in FIG. 17 approximately spherical, not only can the appearance be varied, but also the surface area of the outer tube 101 can be increased.
temperature decreases, and the mercury vapor pressure can be brought closer to the optimum value.

FIG. 18 shows another embodiment according to the present invention, which has a structure (16) in which the open ends of the inner tube 103 are brought into contact with each other. Due to the above structure, a portion of the ultraviolet rays generated near the opening of one inner tube 103 excites the phosphor 104 coated on the inner wall of the other inner tube 103, so that loss of ultraviolet rays can be reduced. .

FIG. 19 shows another embodiment according to the present invention, in which a light reflector/If 128 is provided on the outer surface of the outer tube stem 102, and a connector 122 and a connector pin 123 are also provided. This facilitates connection with the discharge lamp drive circuit.

FIG. 20 shows still another embodiment according to the present invention, in which a discharge lamp drive circuit housing portion 124 and an electric input terminal base 125 are provided on the outside of the outer bulb stem 102. A discharge lamp with this structure is compatible with incandescent light bulbs and is easy to use.

FIG. 21 shows another embodiment according to the invention, in which three inner tubes 103 are provided. The three inner tubes 103 emit light simultaneously or sequentially @tK based on the drive circuit system.

FIG. 22 shows another embodiment according to the present invention, in which one set of electrodes 105 (17) are provided near both ends of the inner tube 103. The inner wall of the outer tube 101 may be coated with a phosphor 104.

In addition to the above embodiments, combinations of the above glaze embodiments are also possible.

The U-shaped inner tube 103 in FIG. 3 does not necessarily have to be U-shaped, and may be further curved in a concave direction.

FIG. 23 shows another embodiment according to the invention, in which one inner tube 103 is generally straight. The discharge path 107 is shown by a dashed line and passes through the inside and outside of both tubes 103. The luminescent substance 104 is provided on any or all of the inner surface and outer surface of the inner tube 103, the inner surface of the outer tube 101, and the inner surface of the outer tube stem 102.

FIG. 24 shows an example of the connection between the inner tube 103 and the outer tube stem 102. By pinching the tip of the inner tube 103, the inner tube 10
3 is fixed to the electrode lead 106. Electrode lead 10
A dielectric layer 126 may be provided on a part of the surface of 6 to provide electrical insulation.

FIG. 25 shows another example of the connection between the inner tube 103 and the outer tube stem 102. A flared stem 127 is provided at the tip of the inner tube, and the electrode lead 106' coming out from the stem is connected to the outer tube stem 10.
It is connected to lead 106 of No. 2. The electrode lead surface may be insulated.

FIG. 26 shows another example of the connection between the inner tube 103 and the outer tube stem 102, in which both are bonded together with an adhesive substance 128 such as glass frit.

As described above, according to the present invention, the fluorescent discharge lamp is compact, highly efficient, has high brightness, has little unevenness in brightness, has a mercury vapor pressure set near the optimum value, and is easy to manufacture in the form of a single-cap light bulb. is obtained.

[Brief explanation of the drawing]

Figures 1 and 2 each show an example of a conventional self-ballasted discharge lamp, Figure 3 shows an example of the structure of a discharge lamp according to the present invention, and Figures 4.5 and 3 show an example of the structure of a discharge lamp according to the present invention. FIGS. 6 to 23 are diagrams showing a front view and side view of a discharge lamp, FIGS. 6 to 23 are views showing slightly modified versions of the structure of a discharge lamp according to the present invention, and FIGS. 24 to 26 are views showing a structure according to the present invention, respectively. FIG. 19 is a diagram illustrating an example of the inner tube fixing method according to FIG. In the figure, 101... outer tube, 102... outer tube stem, 1
03... Inner tube, 104... Fluorescent material, 105... Electrode, 106... Electrode lead, 128... Light reflecting layer. Agent Patent Attorney Toshiyuki Usuda (20) 采 j 口 2 目＜2／＝＝JくEゝ＼Nへ／lOI 4th 口'fJ7 fig. 8 fig. 9 fig. 10 fig. VJtr b'"fI/ 2 Illustration drawing 13 Figure 14 Mouth 15 Figure fI f et al. Figure - "2106 Continuation of page 1 Q Frequent Author: Sobe Ono, 1-280 Higashi-Koigakubo, Kokubunji City, Hitachi, Ltd. Central Research Laboratory @ Inventor: Tano Kato, 1-280 Higashi-Koigakubo, Kokubunji City, Hitachi, Ltd. Inside the Central Research Institute

Claims (1)

[Scope of Claims] 1. A translucent outer tube, an outer tube stem that is integrated with the outer tube and forms an airtight space, and one end of one or more stems provided in the space. In a low-pressure steam discharge lamp comprising an inner tube substantially or completely sealed, and one electrode provided on each side of the sealed end of the inner tube, at least one of the inner tubes A low-pressure steam discharge lamp characterized in that the length of the inner tube is larger than the length of the outer tube by bending the book shape into a roughly U-shape, and the open end of the inner tube is provided near the outer tube stem. 2. A low-pressure steam discharge lamp according to claim 1, characterized in that a luminescent material is provided on the inner wall surface of the inner tube. 3. A low-pressure steam discharge lamp according to claim 1, characterized in that a luminescent material is provided on the inner surface of the outer tube stem and near the open end of the roughly U-shaped inner tube. 4. Scope of % Allowance Required Low pressure steam discharge lamp according to item 1, characterized in that a light reflecting material is provided on the inner or outer surface of the outer tube stem and near the open end of the roughly U-shaped inner tube. discharge lamp. 5.% The low-pressure steam discharge lamp according to claim 1, characterized in that the inner or outer surface of the outer bulb is frosted glass-like or coated with a light-diffusing substance. 6. A low-pressure steam discharge lamp according to claim 1, characterized in that the opening end of the inner tube is formed thick or thin. 7.% The low-pressure steam discharge lamp according to claim 1 is characterized in that a cylinder having at least one opening is provided, and the opening S is disposed near the opening of the inner tube of the discharge lamp. Low pressure steam discharge lamp. 8. A low-pressure steam discharge lamp according to claim 1, characterized in that another electrode is provided near the opening of the inner tube. 9. A low-pressure steam discharge lamp according to claim 1, characterized in that one or more automatically activated ignition devices are provided within the airtight space. 10. In the low-pressure steam discharge lamp according to claim 1, the inner tube is integrated by partially connecting the open ends of the inner tube, and one or more ventilation holes are provided. Characteristic low pressure steam discharge lamp. 11. A low-pressure steam discharge lamp according to claim 1, characterized in that a metal forming a mercury amalgam is provided near the electrodes. 12. A low-pressure steam discharge lamp according to claim 1, characterized in that the open ends of the inner tubes are arranged facing each other. 13. The low-pressure steam discharge lamp according to claim 1, characterized in that a light-reflecting layer is provided on the outer surface of the outer bulb stem.