CN115148576A - Foil sealed short arc mercury lamp - Google Patents
Foil sealed short arc mercury lamp Download PDFInfo
- Publication number
- CN115148576A CN115148576A CN202210947732.6A CN202210947732A CN115148576A CN 115148576 A CN115148576 A CN 115148576A CN 202210947732 A CN202210947732 A CN 202210947732A CN 115148576 A CN115148576 A CN 115148576A
- Authority
- CN
- China
- Prior art keywords
- foil
- electrode support
- support rod
- length
- cap
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J61/00—Gas-discharge or vapour-discharge lamps
- H01J61/02—Details
- H01J61/36—Seals between parts of vessels; Seals for leading-in conductors; Leading-in conductors
- H01J61/361—Seals between parts of vessel
Landscapes
- Vessels And Coating Films For Discharge Lamps (AREA)
Abstract
The invention provides a foil-sealed short-arc mercury lamp with a low incidence of cracks in the sealed portion. A foil-sealed short-arc mercury lamp (1) is a foil-sealed discharge lamp (rated power 13.5 kW), and is provided with a sealing body (3), an anode (4), a cathode (5), a lead bar (7), a cap (9), and beads (6). The sealing body (3) is filled with mercury and xenon gas, and has sealing portions (3 a) at both ends. A cap (9) made of glass is disposed on the sealing portion (3 a). 5 pieces of molybdenum metal foil (13) are provided on the outer periphery of the cap (9). The length (Lb) of the bead (6) is 55mm, and the cap length (Lc) is 40mm (Lb > Lc). Bead length (Lb)/cap length (Lc) (hereinafter referred to as bead-cap ratio) =1.38.
Description
Technical Field
The present invention relates to a foil-sealed short arc mercury lamp, and more particularly to a foil-sealed short arc mercury lamp that suppresses floating near a sealed portion.
Background
Patent document 1 discloses a foil-sealed mercury short arc lamp in which mercury is less likely to aggregate during lighting.
In recent years, the foil-sealed mercury short arc lamp is required to have higher illuminance, and the breakage of the sealed portion is a problem due to the higher load on the lamp.
The cause of the breakage will be briefly described. The sealing of the sealing portion is performed by fusing a molybdenum foil to glass, but the molybdenum foil at the fused portion is peeled from the glass (hereinafter referred to as a floating foil) due to the high load applied to the sealing portion accompanying the high load applied to the lamp. The glass around the gap formed by the floating foil is subjected to thermal stress and internal pressure stress by mercury gas up to several tens of atmospheres at the time of lighting, and thus the vicinity of the sealed portion is broken.
In particular, on the cathode side, in addition to the load due to such thermal stress and internal pressure stress, the following chemical factors are also present: cations such as mercury and metal impurities contained in the glass member are attracted to negative charges, and these damage the bonding between the glass and the molybdenum foil in the seal portion.
Patent document 2 discloses the following technique: by forming the straight portion and the flat portion in the nearly cylindrical glass member, the non-welded region formed between the glass and the molybdenum foil is reduced, and the strength of the seal portion is improved.
Documents of the prior art
Patent document
Patent document 1: japanese patent laid-open No. 2012-186121
Patent document 2: japanese patent laid-open No. 2020-24893
Disclosure of Invention
Problems to be solved by the invention
However, when the glass member of patent document 2 is used, since the linear portion and the flat surface portion are formed, a corner portion is inevitably generated in the nearly cylindrical glass member. Such a corner portion has a problem that cracks or chips are generated in a manufacturing process for forming the sealing portion. Patent document 2 merely improves the strength of the seal portion and does not reduce the load itself on the seal portion.
The invention aims to provide a foil-sealed short-arc mercury lamp which is not easy to generate floating foil.
Means for solving the problems
(1) The foil-sealed short-arc mercury lamp of the present invention includes: a glass sealing body having sealing portions at both ends; an electrode support rod having an electrode at a front end thereof; a glass electrode support rod holding member which is disposed in the sealing portion and supports an end portion of the electrode support rod on the side opposite to the tip end of the electrode support rod; a glass electrode support rod intermediate support member which is disposed adjacent to the electrode side of the electrode support rod holding member and supports the middle of the electrode support rod; 2 or more metal foils disposed on the outer periphery of the electrode support bar holding member and electrically connected to the electrode support bar; wherein the axial length of the electrode support rod intermediate support member is made longer than the length of the electrode support rod holding member. Therefore, floating foil can be prevented, and a foil-sealed short arc mercury lamp with a low crack incidence can be provided.
(2) In the foil-sealed type short arc discharge lamp of the present invention, the length of the intermediate support member of the electrode support bar in the axial direction/the length of the electrode support bar holding member > 1. Therefore, floating foil can be prevented, and a foil-sealed short arc mercury lamp with a low crack incidence can be provided.
(3) In the foil-sealed short arc discharge lamp of the present invention, the rated power is 8kW or more and the mercury amount is 40mg/mL or more. Therefore, a foil-sealed short arc mercury lamp that can prevent foil floating and thus has a low crack occurrence rate can be provided in a so-called large lamp.
Terms used in the claims and corresponding relations between components in the embodiments will be described. The "electrode support rod holding member" corresponds to the cap 9, and the "electrode support rod intermediate support member" corresponds to the bead 6.
Drawings
FIG. 1: an explanatory diagram showing the structure of the sealing part of the short arc discharge lamp 1 of the present invention is shown.
FIG. 2: the drawings are for explaining the temperature measurement method.
FIG. 3: a diagram showing a difference between the first embodiment and the second embodiment.
Detailed Description
1. First embodiment
Fig. 1 shows a main sectional view of a short-arc discharge lamp 1 according to the invention. The short arc discharge lamp 1 is a foil-sealed discharge lamp (rated power 13.5 kW), and includes a sealing body 3, an anode 4, a cathode 5, a lead bar 7, a cap 9, and beads 6.
The sealing body 3 is filled with mercury and xenon gas, and has sealing portions 3a at both ends. A cap 9 made of glass is disposed in the sealing portion 3a. The cap 9 has a proximal end into which the lead bar 7 is inserted at a distal end thereof, and the cap 9 supports the lead bar 7. On the outer periphery of the cap 9, 5 pieces of molybdenum metal foil 13 were provided as a conductive member for conducting electricity to the cathode 5. A metal plate 15 having a through hole into which the lead bar 7 is inserted is provided at the tip of the cap 9.
In the present embodiment, the amount of mercury is 40mg/mL and the gas is 700Torr.
The lead bar 7 and the cap 18 are electrically connected to the metal foil 13, the electric board (not shown), the rear lead bar 17, and the cap 18, whereby the cathode 5 provided at the tip of the lead bar 7 can be externally energized.
The beads 6 will be described with reference to fig. 1B. The bead 6 is made of glass, and has substantially the same diameter as the metal plate 15 at the tip of the cap 9 at one end on the cap 9 side. Further, a through hole 29 into which the lead bar 7 is inserted is provided in the center.
In the present embodiment, the length Lb of the bead 6 is set to 55mm, and the cap length Lc is set to 40mm (Lb > Lc). Bead length Lb/cap length Lc (hereinafter referred to as bead-cap ratio) =1.38. Incidentally, conventionally, lb was 35mm, and the cap length Lc was 60mm (bead-cap ratio was 0.6).
Further, 3 lamps of the conventional standard and 2 lamps of the bead/cap ratio of the embodiment shown in fig. 1 were produced, and the length of the floating foil was measured for these 5 lamps.
In each lamp, 5 metal foils were used on the cathode side, and floating foils were likely to be present on the front side and the back side, respectively. That is, the floating foil length (axial distance from the end of the metal gasket 15 on the base side on the cathode side) and the occurrence of cracks were examined for 5 pieces × 2 (front and back) =50 in total.
With respect to the bead-cap ratio lamps of the embodiment shown in fig. 1, 2 lamps were lit for 1000 hours, and 1 lamp had no floating foil.
In contrast, as shown in table 1, the lighting time of each of the 3 conventional lamps was 169 hours. The number of 1 floating foils having no cracks and 3mm or less was 9 (comparative example 1). In addition, the number of floating foils having cracks and 34mm or less was 10 in 1 (comparative example 2). The number of the other 1 floating foils having no cracks and no more than 22mm was 10 (comparative example 3).
TABLE 1
The lighting test was performed in an excessive input state (a state in which the input power is 14.2kW with respect to the rated power of 13.5kW and the periphery of the seal portion is covered with the tubular member having the wool fabric on the inner wall), and in general, even if the rated power is 13.5kW, the lighting test was initially used from about 10kW, and therefore the input power of 14.2kW was 1.4 times or more the excessive input state.
The reason why the floating foil is reduced is not clear, but the inventors believe that the temperature of the fused portion is reduced by reducing the temperature of the metal foil 13 at the time of lighting, that is, by increasing the length of the beads to keep the distance between the metal foil and the light-emitting portion as the heat source, and thereby the temperature of the fused portion is reduced, and thus the destruction of the bond between the quartz glass and the molybdenum foil by the metal cations that have migrated to the sealed portion can be suppressed. The floating foil of the seal portion and the breakage associated therewith are considered to be caused by the following two influences: the strength is reduced by the destruction of the bonding interface due to the chemical reaction between the product (Mo — O — Si compound) at the bonding interface between the quartz glass and the molybdenum foil and the metal cation transferred to the sealing portion, and by the stress deformation due to the difference in thermal expansion between the metal foil and the glass. By lowering the temperature, the chemical reaction rate is lowered and the stress deformation is also reduced, so that the strength reduction due to two factors is alleviated and the breakage can be prevented.
It is conventionally thought that if the axial length of the bead 6 is increased, the mercury that has not evaporated accumulates in the gap between the through hole 29 and the lead bar 7, and the problem of an increase in the startup time arises. However, even if the bead-cap ratio is set to 1 or more as in the present invention, there is no particular disadvantage described above.
The inventors measured the temperature of the metal foil 13. The temperature measurement method in the present embodiment will be described with reference to fig. 2.
The short arc discharge lamp 1 is vertically disposed in a cubic lamp housing 50 having a side of about 1m such that the anode 4 is positioned above. In order to prevent the influence of light radiated from the cathode 5, a light shielding box 51 covering the vicinity of the sealing portion on the cathode 5 side is provided in the lamp housing 50. The inner surface of the light shielding box 51 is coated with black body paint. A radiation thermometer (a 6261 manufactured by FLIR corporation) (not shown) is installed through the measurement window 53 of the globe 50 so as to be perpendicular to the metal foil 13. The emissivity was set to 0.37.
After the short arc discharge lamp 1 was turned on at a voltage of 108V and a dc current of 92.6A to be in a steady state, the temperature after 4 milliseconds had elapsed since the lamp was turned off was measured by a radiation thermometer. This is to prevent the arc light at the time of lamp lighting from affecting the measured value.
In the temperature measurement, the voltage 108V and the dc current 92.6A are turned on to have the same input power as those used under a constant condition of general illuminance. That is, even if the rated power is 13.5kW, the rated power is initially used at about 10kW, and when the illuminance decreases with use, the rated power is increased for use.
The temperature of the metal foil 13 is reduced by about 40 degrees on average in the short-arc discharge lamp 1 compared to the existing products.
In order to confirm the correlation between the foil floating and the cracks in the seal portion, the inventors examined the floating foil length and the crack occurrence rate for 51 lamps (5 foils/root, and 510 total positions on the front side and the back side) collected from customers in the past. The results are shown in Table 2. Of the 51, 4 developed cracks. In addition, cracks were generated from 2 foils as starting points in 1 of the 4 foils.
TABLE 2
| Crack(s) | Time of use | TABLE 1 | TABLE 2 | TABLE 3 | TABLE 4 | TABLE 5 | Back 1 | Back 2 | Back 3 | Back 4 | Back 5 | |
| 1 | Is provided with | 140 | 3 | 8 | 8 | 30 | 30 | 25 | 33 | 33 | 33 | 33 |
| 2 | Is free of | 536 | 4 | 4 | 4 | 4 | 4 | 3 | 2 | 3 | 3 | 3 |
| … | … | … | … | … | … | … | … | … | … | … | … | … |
| 31 | Is free of | 1344 | 3 | 3 | 3 | 3 | 3 | 0 | 0 | 0 | 0 | 0 |
| 32 | Is provided with | 873 | 2 | 4 | 5 | 2 | 0 | 3 | 22 | 5 | 21 | 3 |
| 33 | Is free of | 1344 | 4 | 4 | 4 | 4 | 5 | 0 | 0 | 0 | 0 | 0 |
| 34 | Is free of | 1018 | 7 | 7 | 5 | 5 | 5 | 11 | 20 | 22 | 8 | 6 |
| 35 | Is provided with | 405 | 2 | 2 | 3 | 3 | 2 | 0 | 0 | 0 | 30 | 0 |
| 36 | Is free of | 461 | 1 | 2 | 2 | 2 | 2 | 0 | 3 | 2 | 2 | 2 |
| … | … | … | … | … | … | … | … | … | … | … | … | … |
| 50 | Is free of | 666 | 8 | 8 | 8 | 8 | 8 | 6 | 7 | 5 | 5 | 6 |
| 51 | Is provided with | 1000 | 4 | 4 | 4 | 4 | 4 | 4 | 19 | 16 | 4 | 5 |
For 510 of table 2, the statistical results are shown in table 3. In this way, in the conventional product, 109/510=21.4% had no floating foil, and in addition, floating foil was generated. In addition, regarding the case where cracks were generated among them, for foils having a floating foil length of 26mm or more, 63% of them were cracked; for the foil with the length of the floating foil ranging from 21mm to 25mm, 17 percent of the floating foil generates cracks; for foils with a floating foil length of 16-20 mm, 14% of them are cracked; for foils with a floating foil length of 1 to 5mm, 1% cracks occurred.
TABLE 3
Thus, the longer the length of the foil, the higher the incidence of cracking. In contrast, the crack occurrence rate of the lamp without the floating foil was 0 even in the conventional lamp.
In addition, the crack ratio means: the number of parts having cracks is 10 in total, and the denominator indicates the data interval in which the parts are distributed. In this case, 5 is a foil having a floating foil length of 26mm or more.
2. Second embodiment
In the first embodiment, the taper length of the tip of the cap 9 was 21mm, but a short arc discharge lamp having a taper length of 4mm was manufactured. The taper angle of the cap 9 is 10 to 46 degrees in terms of calculation. Fig. 3A and B show seal part diagrams of the first and second embodiments. 5 short arc discharge lamps were produced using the seal part member diagram.
In this embodiment, even when the lighting was performed for 120 hours in the above-described over-input test (in a state where the input power was 14.2kW with respect to the rated power of 13.5kW and the periphery of the seal portion was covered with the tubular member having the wool lining on the inner wall), the foil was "free" and "no" crack was found.
By increasing the taper angle of the cap 9 in this manner, the possibility of floating the foil becomes low as described below.
Generally, the cross section of the foil in the width direction becomes thinner toward the end (blade edge). This is to improve the adhesion of the end portion. However, in the tapered portion of the bead, the side faces of the metal foils were cut off in order to avoid overlapping of 5 pieces of metal foils with each other. As a result, the blade portion also disappears. The portion where the blade does not exist is liable to cause foil floating. If the length of the tapered portion can be shortened, the length of the portion where the blade does not exist is shortened, and therefore the possibility of foil floating is reduced.
3. Other embodiments
In the present embodiment, a short-arc mercury lamp having a rated power of 13.5kW is explained. However, the rated power is not limited thereto.
Generally, the higher the rated power, the higher the internal pressure; the higher the internal pressure, the more likely the floating foil occurs. However, even if the rated power is high, the cracks may not be generated as much. This is because even if the rated power is high, there is a lamp whose internal pressure is not so high. The inventors examined conventional lamps and found that when the rated power is 8kW or more and the mercury amount per unit volume exceeds 40mg/mL, a floating foil is generated to such an extent that cracks are generated. Therefore, the present invention is useful for a foil-sealed short arc mercury lamp having a rated power of 8kW or more and a mercury amount of 40mg/mL or more.
In the present embodiment, the case where the bead cap ratio is 1.38 has been described, but the present invention is not limited thereto, and the bead cap ratio may be 1 or more.
In the present embodiment, the bead caps are made larger than those of the related art, thereby preventing floating of the foil. Therefore, the length of the bead can be extended without changing the distance from the reference surface to the cathode.
Description of the symbols
Short arc discharge lamp
Sealing body
Sealing part
Anode of a new design
Cathode
Bead
7
A cap
A metal foil
A metal plate
A light-shielding box.
Claims (3)
1. A foil-sealed short-arc mercury lamp, comprising:
a glass sealing body having sealing portions at both ends;
an electrode support rod having an electrode at a front end thereof;
a glass electrode support rod holding member which is disposed in the sealing portion and supports an end portion on the opposite side to the tip end of the electrode support rod;
a glass electrode support rod intermediate support member which is disposed adjacent to the electrode side of the electrode support rod holding member and supports the middle of the electrode support rod;
2 or more metal foils disposed on the outer periphery of the electrode support bar holding member and electrically connected to the electrode support bar;
wherein the axial length of the electrode support rod intermediate support member is made longer than the length of the electrode support rod holding member.
2. A foil-sealed short-arc mercury lamp, comprising:
a glass sealing body having sealing portions at both ends;
an electrode support rod having an electrode at a front end thereof;
a glass electrode support rod holding member which is disposed in the sealing portion and supports an end portion on the opposite side to the tip end of the electrode support rod;
a glass electrode support rod intermediate support member which is disposed adjacent to the electrode side of the electrode support rod holding member and supports the middle of the electrode support rod;
2 or more metal foils disposed on the outer periphery of the electrode support bar holding member and electrically connected to the electrode support bar;
characterized in that the length of the electrode support bar intermediate support member in the axial direction/the length of the electrode support bar holding member > 1 is set.
3. Foil-sealed short arc mercury lamp according to claim 1 or 2,
the rated power is more than 8kW and the mercury amount is more than 40 mg/mL.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210947732.6A CN115148576A (en) | 2022-08-05 | 2022-08-05 | Foil sealed short arc mercury lamp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210947732.6A CN115148576A (en) | 2022-08-05 | 2022-08-05 | Foil sealed short arc mercury lamp |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115148576A true CN115148576A (en) | 2022-10-04 |
Family
ID=83414490
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210947732.6A Pending CN115148576A (en) | 2022-08-05 | 2022-08-05 | Foil sealed short arc mercury lamp |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115148576A (en) |
-
2022
- 2022-08-05 CN CN202210947732.6A patent/CN115148576A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100822583B1 (en) | High pressure discharge lamp | |
| US6903509B2 (en) | Ultrahigh pressure discharge lamp of the short arc type with improved metal foil to electrode connection arrangement | |
| JP2007134055A (en) | Arc tube for discharge lamp apparatus | |
| EP1134781A2 (en) | High-voltage discharge lamp | |
| US6891332B1 (en) | Arc tube capable of preventing occurrence of leak due to cracks and manufacturing method therefore | |
| EP1296356B1 (en) | Super-high pressure discharge lamp of the short arc type | |
| JPWO2008129745A1 (en) | Foil seal lamp | |
| KR102190649B1 (en) | Discharge lamp | |
| US6825614B2 (en) | Short-arc discharge lamp | |
| CN115148576A (en) | Foil sealed short arc mercury lamp | |
| US20090295290A1 (en) | Metal lead-through structure and lamp with metal lead-through | |
| US20100295448A1 (en) | Vehicle discharge lamp | |
| JP7149631B2 (en) | Foil-sealed short-arc mercury lamp | |
| US8222817B2 (en) | Arc tube for discharge bulb and discharge bulb including the same | |
| CN109314038B (en) | UV low-pressure mercury lamp with amalgam deposit | |
| US20070035252A1 (en) | Current bushing system for a lamp | |
| JP7141692B2 (en) | Sealing structure for discharge lamp, and discharge lamp provided with the structure | |
| CN207852614U (en) | Discharge lamp | |
| JP3634692B2 (en) | Discharge bulb | |
| JP2008004385A (en) | Discharge lamp for automobile | |
| KR20070093969A (en) | Cold cathode fluorescent lamp | |
| JP5773252B2 (en) | Short arc type discharge lamp | |
| US8022630B2 (en) | High intensity discharge lamp with corrosion-resistant electrical connector | |
| JP2012084244A (en) | Long arc type discharge lamp | |
| JP5956790B2 (en) | Discharge lamp |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |