JP5243930B2 - Low pressure mercury vapor discharge single-neck fluorescent lamp - Google Patents

Description

  The present invention relates to a low-pressure mercury vapor discharge single-neck fluorescent lamp using a U tube, and when the ambient temperature is 25 ° C., the coldest point, which is the coldest part in the discharge tube, has a self-heating and ambient temperature. The present invention relates to a low-pressure mercury vapor discharge single-neck fluorescent lamp that does not perform mercury amalgam regulation and maximizes the brightness of the lamp so as to be optimal in correlation.

A conventional low-pressure discharge lamp using a U-tube is configured as shown in FIG. 6 and FIG. 7 showing a low-pressure discharge lamp bent once, and the arc tube 1 formed of a U-tube has two longitudinal directions. Tube sections 2, 3 and transverse tube section 4 are provided. U-shaped bent portion of the arc tube 1 has an outer generatrix M _Q in the transverse tube section 4 is linear, and configured to extend substantially perpendicular to the outer generating line M _L in both the longitudinal tube section 2 and 3 Has been. The diameter D _L of the longitudinal tube sections 2 and 3 is 12 mm, the diameter D _Q of the transverse tube section 4 is selected at its center and D _Q / _DL is approximately 1.2, It is sufficient that _DQ is equal to or larger than the diameter D _L. Furthermore, the tube transition between the longitudinal tube sections 2, 3 and the transverse tube section 4 extends such that the ratio of the diameter D _{LQ to} the diameter D _{Q at the} tube bend is about 1.2. The diameter D _LQ only needs to be larger than the diameter D _Q.

  FIG. 8 is a graph showing the temperature distribution of the low-pressure discharge lamp bent once in FIGS. 6 and 7 and measured at an ambient temperature of about 25 ° C. FIG. From the figure, the cold spot that determines the mercury vapor pressure during lamp operation is present in the tube bends 5 and 6 and its temperature is approximately 40 ° C. The temperature increases to 70 ° C. in the direction of the sealed end with the electrode. The central part of the transverse tube section 4 is 45 ° C., 5 ° C. higher than the cold spot.

In this way, an optimum mercury vapor pressure is achieved during lamp operation by the cold portions in the outer tube bending portions 5 and 6 (see, for example, Patent Document 1).
Japanese Examined Patent Publication No. 2-53906 JP 2002-15701 A JP 2002-270134 A Japanese Utility Model Publication No. 9-70

A conventional low-pressure discharge lamp using a U-tube has a diameter D _Q equal to or larger than a diameter D _L and a diameter D _LQ larger than the diameter D _Q so that the longitudinal tube sections 2, 3 and the horizontal Although the coldest spot temperature is lowered by extending the pipe transition portion between the directional pipe section 4 outward, the result of the verification (details will be described later) shows that the coldest spot temperature is still 5-10. ℃ too high.

  As an improvement measure, for example, there is means for adding a chevron portion in the length direction of the lamp in the transverse tube section 4, which has the effect of lowering the coldest spot temperature, but the total length becomes longer, so there is no compatibility and practical use. It lacks sex.

  Further, as another improvement measure, the coldest spot temperature can be lowered by providing the vertical pipe sections 2 and 3 in the vicinity of the horizontal pipe section 4 with protrusions in the perpendicular direction. In a lamp using a U tube, the protruding portions of each other may come into contact with each other and crack, which is inferior in productivity and impossible.

  The present invention has been made to solve the above-described problems, and is a low-pressure mercury capable of lowering the coldest point temperature to an optimum temperature without lowering the equipment mounting rate, increasing the manufacturing failure rate, and so on. An object of the present invention is to provide a vapor discharge single-piece fluorescent lamp.

The low-pressure mercury vapor discharge single-neck fluorescent lamp according to the present invention uses a U tube with a tube outer diameter of 16 mm or less and a lamp current of 290 mA or more, and each U tube extends at intervals close to each other in parallel. A straight longitudinal tube section, a transverse tube section connecting the respective longitudinal tube sections, and a tube bend at the transition between the longitudinal tube section and the transverse tube section. In a low-pressure mercury vapor discharge single-neck fluorescent lamp that does not regulate mercury vapor pressure, a discharge path is formed on the outer bus _MLQ side of the bent portion of the transition between the vertical tube section and the horizontal tube section. The tube inner diameter at the center of the transverse tube section is D _Q , and the tube inner diameter of the cross section perpendicular to the discharge path at the tube bending portion (inside the tube from the inner bus to the outer bus _MLQ direction) When the distance is D _LQ ,
D _LQ > D _Q
It is characterized by satisfying.

Further, the low-pressure mercury vapor discharge single-neck fluorescent lamp according to the present invention uses a U tube with a tube outer diameter of 16 mm or less and a lamp current of 290 mA or more, and each U tube extends at intervals close to each other. Two straight longitudinal tube segments, one transverse tube segment connecting each longitudinal tube segment, and a tube bend at the transition between the longitudinal tube segment and the transverse tube segment In a low-pressure mercury vapor discharge single-neck fluorescent lamp that does not regulate mercury vapor pressure, a constricted portion on the outer bus _MLQ side of the bent portion of the transition portion between the vertical tube section and the horizontal tube section The tube inner diameter is D _L , the tube inner diameter of the central portion of the transverse tube section is D _Q , and the tube inner diameter of the cross section orthogonal to the discharge path in the tube bent portion (from the inner bus line of the tube bent portion to the outer bus _MLQ direction) tube length) to _{D LQ,} the width of the narrowed portion w, the length of the narrowed portion _{(D L} When the same direction) was used as a h and,
D _LQ > D _Q
0.1D _L ≤ w ≤ 0.2D _L
0.03D _LQ ≤ h ≤ 0.10D _LQ
It is characterized by satisfying.

  In addition, the low-pressure mercury vapor discharge single-neck fluorescent lamp according to the present invention is characterized by comprising a 2U tube having a tube outer diameter of 12 mm.

  By configuring the low-pressure mercury vapor discharge single-piece fluorescent lamp according to the present invention as described above, it is possible to reduce the coldest spot temperature to the optimum temperature without reducing the equipment mounting rate, increasing the manufacturing defect rate. it can.

Embodiment 1 FIG.
1 to 5 are diagrams showing Embodiment 1, FIG. 1 is a diagram showing a configuration of a low-pressure mercury vapor discharge single-piece fluorescent lamp, and FIG. 2 is a tip portion of a low-pressure mercury vapor discharge single-piece fluorescent lamp compared with a conventional one. FIG. 3 is a partial cross-sectional view of one U tube of the 3U tube fluorescent lamp used for the verification, and FIG. 4 is orthogonal to the discharge path at the tube transition portion between the vertical tube section and the horizontal tube section. FIG. 5 is a diagram comparing the ambient temperature and relative illuminance with a conventional one.

  The low-pressure mercury vapor discharge single-neck fluorescent lamp in the first embodiment extends the tube transition portion between the longitudinal tube sections 2 and 3 and the lateral tube section 4 to the outside, and the longitudinal tube sections 2 and 3. Characterized by the shape of the tube bends 5, 6 at the transition between the transverse tube section 4. The tube bent portions 5 and 6 are provided with constricted portions, and the constricted portions are unlikely to become discharge paths, so that the coldest spot is formed here, and the coldest spot temperature can be remarkably lowered.

  The overall structure of the low-pressure mercury vapor discharge single-piece fluorescent lamp is the same as the conventional one as shown in FIG. However, the arc tube 1 uses three U tubes, and each U tube includes two longitudinal tube sections 2 and 3 and a lateral tube section 4. The tube outer diameter of the U tube is 12 mm.

  As shown in FIG. 2, the fluorescent lamp of the present embodiment has a transition tube between the longitudinal tube sections 2 and 3 and the transverse tube section 4 as can be seen from the conventional example shown in FIG. The bends 5 and 6 are extended outwards, and a throttle 7 is provided at the tube bends 5 and 6 at the transition between the longitudinal tube sections 2 and 3 and the transverse tube section 4. The restricting portion 7 may have any shape that does not easily become a discharge path while the arc tube 1 is lit and can store liquid mercury.

Next, the specifications of an embodiment of a low-pressure mercury vapor discharge single-neck fluorescent lamp (model name FHT57EX-N) actually produced as a prototype will be described.
As shown in FIGS. 3 and 4, each U tube of the prototype 3U tube fluorescent lamp has a tube outer diameter of 12 mm, a tube inner diameter D _L = 9.4 mm, and a tube inner diameter D _{Q at} the center of the transverse tube section 4. = 11.5 mm, (outer generatrix _{M LQ} direction tract distance from the inside _bus) tube inner diameter of the cross-section perpendicular to the discharge path in the tube bending portion 5,6 D LQ = 14.85mm, width w = 1 diaphragm portion 7. 9 mm, the length of the diaphragm 7 (the same direction as D _LQ ) h = 0.45 mm. The throttle portion 7 is provided on the outer bus _MLQ side of the tube bending portions 5 and 6.

For comparison, a sample in which the narrowed portion 7 is not provided in the tube bending portions 5 and 6 was also prototyped (conventional example). The specifications are the same as those of the example except that the tube bending portions 5 and 6 do not have the throttle portion 7. Therefore,
D _LQ = 14.85 mm> D _Q = 11.5 mm> D _L = 9.4 mm
Therefore, the conditions of Patent Document 1 shown in the background art are satisfied.

FIG. 5 shows the result of the lighting test of the lamps of the above examples and conventional examples.
In a 3U tube fluorescent lamp having a tube outer diameter of 12 mm, the relative illuminance is greatest when the coldest spot temperature is 52 ° C. at an ambient temperature of 25 ° C.
In the conventional 3U tube fluorescent lamp, at the ambient temperature of 25 ° C., the coldest spot temperature becomes 60 ° C., and the relative illuminance deviates from the peak as shown in FIG.
On the other hand, in the 3U tube fluorescent lamp of the example, at the ambient temperature of 25 ° C., the coldest spot temperature becomes 52 ° C., and the relative illuminance almost coincides with the peak as shown in FIG.
There is a difference of about 8 ° C. in the ambient temperature at which the relative illuminance peaks between the example and the conventional example. This corresponds to the difference in the coldest spot temperature at an ambient temperature of 25 ° C. (60−52 = 8 ° C.).

From this verification, it can be seen that the coldest spot temperature is significantly lowered by providing the narrowed portion 7 on the outer bus _MLQ side of the tube bent portions 5 and 6 as in the embodiment.

From the above verification results, the conditions for lowering the coldest spot temperature are summarized as follows:
Width w ≦ 0.2D _L of diaphragm 7 (In the embodiment, since width w = 1.9 mm and D _L = 9.4 mm, w = 0.2D _L , and the diaphragm 7 is unlikely to be a discharge path. in order, the w ≦ 0.2D _L from a technical common sense).
However, if w of the diaphragm portion 7 is too small, the glass becomes thin, causing a problem in strength. Therefore, there is a lower limit, after all,
0.1D _L ≤ w ≤ 0.2D _L
Is one condition.

The length h of the diaphragm 7 is 0.03D _LQ ≦ h (in the embodiment, h = 0.45 mm and D _LQ = 14.85 mm, so 0.03D _LQ = h, and the diaphragm 7 In order to become the coldest point, 0.03D _LQ ≦ h from technical common sense).
However, if the h of the diaphragm portion 7 is too large, the glass becomes thin, causing a problem in strength. Therefore, there is an upper limit, after all,
0.03D _LQ ≤ h ≤ 0.10D _LQ
Is one other condition.

In addition, the relationship between the tube inner diameter D _LQ and the tube inner diameter D _Q of the cross section perpendicular to the discharge path in the tube bending portions 5 and 6 is as follows.
D _LQ / D _Q > 1.2 (In the embodiment, D _LQ = 14.85 mm, D _Q = 11.5 mm, D _LQ / D _Q = 1.29, and D _LQ should be longer. Is obvious). Therefore,
D _LQ / D _Q > 1.2
Is another condition.

A lateral tube section inner tube diameter D _Q of the central portion of 4, for the relationship between the inner tube diameter D _L, the case of providing the outer generatrix M throttle portion 7 on the _LQ side of the pipe bending portion 5, 6 as examples , D _Q <D _L, it is estimated that the coldest spot temperature is lowered by the narrowed portion 7, so that it is not particularly necessary.

  The verification was performed using a 3U tube fluorescent lamp with a tube outer diameter of 12 mm. However, the above conditions could be satisfied even with a 2U tube fluorescent lamp with an outermost diameter of 16 mm and an optimum cold spot temperature of 50 ° C. at an ambient temperature of 25 ° C. Thus, the coldest spot temperature can be lowered to a temperature close to the optimum. Therefore, the tube outer diameter of 16 mm is a target.

  Moreover, although it is lamp current, if less than 290 mA, since the heat_generation | fever of a lamp | ramp is small, the problem regarding a cold spot will not generate | occur | produce. Therefore, fluorescent lamps having a lamp current of 290 mA or more are targeted.

  In addition, the target single-piece fluorescent lamp is a low-pressure mercury vapor discharge single-piece fluorescent lamp that does not regulate mercury vapor pressure.

FIG. 2 shows the first embodiment, and is a diagram showing a configuration of a low-pressure mercury vapor discharge single-piece fluorescent lamp. It is a figure which shows Embodiment 1, and is a perspective view near the front-end | tip part of the low pressure mercury vapor discharge single-piece | base fluorescent lamp compared with the conventional one. It is a figure which shows Embodiment 1, and is a fragmentary sectional view of one U pipe | tube of the 3U pipe | tube fluorescent lamp used for verification. It is a figure which shows Embodiment 1, and is a figure which shows the shape of the cross section orthogonal to the discharge path in the division pole part of the transition part between a vertical direction pipe | tube division and a horizontal direction pipe | tube division. It is a figure which shows Embodiment 1, and is a figure which compared ambient temperature and relative illumination intensity with the conventional one. It is a figure of the low pressure discharge lamp which has the edge part with the conventional nozzle | cap | die. It is sectional drawing of the low voltage | pressure discharge tube which has not attached the nozzle | cap | die provided with the conventional discharge tube bent once. It is a figure which shows the temperature distribution of the conventional low pressure discharge lamp.

Explanation of symbols

  1 Arc tube, 2, 3 Longitudinal tube section, 4 Transverse tube section, 5, 6 Bent part, 7 Constriction part.

Claims (2)

In a low-pressure mercury vapor discharge single-neck fluorescent lamp with a lamp current of 290 mA or more and no mercury vapor pressure regulation by mercury amalgam.
It has a U tube made of glass with a tube outer diameter of 16 mm or less,
The U tube is
A pair of tube bends that bend the discharge path halfway;
A pair of throttle portions formed in a projecting manner on the outside of the pair of tube bent portions,
The throttle portion is provided on the outer bus _MLQ side of the tube bending portion, and has a recess that is difficult to form a discharge path from the tube inner wall of the tube bending portion toward the tube outer wall,
The narrowed portion has a protruding portion formed in a protruding shape from the tube outer wall of the tube bending portion toward the outside corresponding to the recess ,
The U tube is
The inner tube diameter and D _L, when the width of the narrowed portion and a w,
0.1D _L ≤ w ≤ 0.2D _L
While satisfying
When the tube inner diameter of the cross-section perpendicular to the discharge path in the tube bends have the narrowed portion and D _LQ, and the length of the narrowed portion in the same direction as the D _LQ is h,
0.03D _LQ ≤ h ≤ 0.10D _LQ
A low-pressure mercury vapor discharge single-neck fluorescent lamp characterized by satisfying The low-pressure mercury vapor discharge single base fluorescent lamps, 3U tube outer diameter 12 mm, or, claim 1 Symbol placement of the low-pressure mercury vapor discharge single base fluorescent lamps, characterized by being configured with 2U tube outer tube diameter 16mm .

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