JP2019067753A - Low pressure mercury lamp and method of manufacturing the same - Google Patents

Abstract

To provide a low pressure mercury lamp in which amalgam in a luminous tube is stably fixed at a predetermined position and which maintains ultraviolet light intensity high. and a method of manufacturing the low pressure mercury lamp.SOLUTION: A method of manufacturing f a low pressure mercury lamp according to the present invention includes an amalgam fixing method comprising: inserting an electrode mount having a metallic press into a luminous tube; positioning the metallic press in the vicinity of a recess formed in the inner surface of the luminous tube; pinch-sealing the end of the luminous tube; sealing amalgam into the luminous tube through an exhaust pipe; evacuating the luminous tube; heating-welding the amalgam to the metallic press and the recess formed in the luminous tube, thereby fixing the amalgam to the recess of the luminous tube.SELECTED DRAWING: Figure 3C

Description

  The present invention relates to a low pressure mercury lamp and a method of manufacturing the same.

  The low pressure mercury lamp is a lamp using an arc discharge in which the mercury vapor pressure in the luminous tube during lighting is 100 Pa or less. Low-pressure mercury lamps are mainly used in running water sterilizers, ultraviolet oxidized water treatment devices, and the like. As a representative example of a water treatment tank using a low pressure mercury lamp, there is a running water sterilization treatment apparatus used in a septic tank for beverages, and an ultraviolet oxidation water treatment apparatus for producing ultrapure water used in semiconductor production.

  The ultraviolet oxidation water treatment apparatus will be described as an example. FIG. 1A is a view showing a horizontal water treatment tank 10-1 in which a plurality of water cooling jackets (also referred to as "sleeves") 6 are arranged in the horizontal direction. On the other hand, FIG. 1B is a view showing a vertical water treatment tank 10-2 in which a plurality of water cooling jackets 6 are vertically arranged. In any of the water treatment tanks 10-1 and 10-2, water to be treated is supplied from the water supply port 2 to the inside of the water treatment tank, subjected to ultraviolet light treatment while passing around the water cooling jacket 6, and from the drainage port 4 It is drained to the outside. In a large scale plant water treatment tank, hundreds of low pressure mercury lamps 8 are provided, and the amount of water to be treated reaches up to 400,000 tons / day.

  FIG. 2A is a view for explaining the configuration of a low pressure mercury lamp. Inside each water cooling jacket 6, as shown in FIG. 2A, one light emitting tube 8-1 having bases 12-1 and 12-2 at both ends is inserted, and the bases 12-1 and 12-2 are inserted. Is in contact with the inner circumferential surface of the water cooling jacket 6.

The luminous efficiency of the low pressure mercury lamp 8 is determined by the coldest temperature of the lamp located near the bases 12-1 and 12-2. While the lamp is on, by cooling the bases 12-1 and 12-2 to maintain the coldest temperature of the lamp at a predetermined temperature (35 to 45 ° C.), the lamp can be turned on at high illuminance.
The low pressure mercury lamp 8 contains mercury or amalgam (an alloy of mercury and another metal).

JP-A-2006-209993 "Method of manufacturing low-pressure mercury vapor discharge lamp and low-pressure mercury vapor discharge lamp" (publication date 2006/08/10) Applicant: Nippon Electric Co., Ltd. (patent No. 4621508) JP-A-2010-535396 "Low-pressure mercury discharge lamp with amalgam capsule with amalgam chamber" (published on 2010/11/18) Applicant: Corning Krekka Philips Electronics NV (Patent No. 5174148)

  In the low pressure mercury lamp, in order to stably maintain the luminous efficiency of the lamp, it is preferable to fix the amalgam to the coldest portion located in the vicinity of the electrode in the luminous bulb. For this reason, the amalgam was fixed by heating and welding to the inner wall of the light emitting tube positioned at the coldest portion.

However, the amalgam may move from a predetermined location of the light emitting tube when the lamp is turned on in an external force such as vibration during transportation of the lamp or in the vertical water treatment tank.
When the amalgam moves from a predetermined location of the arc tube, the mercury vapor pressure in the arc tube fluctuates at the time of lamp light emission, deviates from the proper operating temperature, and the amount of ultraviolet radiation is attenuated.

  Therefore, an object of the present invention is to provide a low-pressure mercury lamp in which the amalgam in the luminous bulb is stably fixed at a predetermined position and the ultraviolet intensity is maintained high, and a method of manufacturing the same.

  In view of the above object, in the method for manufacturing a low pressure mercury lamp according to the present invention, in one aspect of the invention, an electrode mount having a metallic clamp is inserted into a luminous bulb, and the metallic clamp is formed on the inner surface of the luminous bulb. Positioning in the vicinity of the recessed portion, pinching the end of the light emitting tube, sealing amalgam into the light emitting tube via an exhaust pipe, evacuating the light emitting tube, and holding the amalgam in the metal retainer And fixing the heat sink to the recess formed in the light emitting tube to fix the light emitting tube to the recess of the light emitting tube.

  Further, in the low pressure mercury lamp according to the present invention, according to one aspect of the present invention, there is provided an arc tube having a recess formed on the inner surface in the vicinity of each end, a metal presser, and an electrode mount inserted in the arc tube. And an amalgam positioned in the recess, wherein the metal retainer is disposed to cover at least a portion of the amalgam.

Furthermore, in the low pressure mercury lamp according to the present invention, the amalgam may be positioned and fixed in the recess by heat welding.
Furthermore, in the low pressure mercury lamp according to the present invention, the metal holder may be provided with a metal foil having elasticity.
Furthermore, in the low pressure mercury lamp according to the present invention, the metal holder may have an elastic metal foil.

Furthermore, in the low pressure mercury lamp according to the present invention, the metal foil may be formed of a metal selected from the group consisting of molybdenum Mo, tungsten W, nickel Ni, niobium Nb, and aluminum Al.
Furthermore, in the low pressure mercury lamp according to the present invention, the electrode mount may have a glass stay, and the metal foil may be attached to a lead rod held by the glass stay.
Furthermore, in the low pressure mercury lamp according to the present invention, a part of the lead rod may extend in the direction of a recess formed in the light emitting tube.
Furthermore, in the low pressure mercury lamp according to the present invention, the lead bar includes a first lead bar fixed to the glass stay and a second lead bar connected to the first lead bar, The metal foil may be attached to the tip of the second lead rod.

  According to the present invention, it is possible to provide a low pressure mercury lamp in which the amalgam in the luminous bulb is stably fixed at a predetermined position and the ultraviolet intensity is maintained high, and a method of manufacturing the same.

FIG. 1A is a view showing an ultraviolet oxidized water treatment apparatus in which a low pressure mercury lamp is used, and is a view for explaining a horizontal water treatment tank in which a plurality of water cooling jackets are arranged in the horizontal direction. FIG. 1B is a view showing an ultraviolet oxidized water treatment apparatus in which a low pressure mercury lamp is used, and is a view for explaining a vertical water treatment tank in which a plurality of water cooling jackets are arranged in the vertical direction. FIG. 2A is a view for explaining the configuration of a low pressure mercury lamp. FIG. 2B is a view for explaining the positional relationship between the arc tube, the base, and the water cooling jacket in the vicinity of the end of the arc tube of the low pressure mercury lamp shown in FIG. 2A. FIG. 3A is a side view of a single electrode mount with a metal hold down on one side. FIG. 3B is a front view of a single electrode mount with a metal hold down on one side. FIG. 3C is a partial cross-sectional view of the vicinity of the end portion of the light emitting tube as viewed from a plane including the lamp axis of the light emitting tube of the low pressure mercury lamp shown in FIG. 2A. FIG. 3D is a partial cutaway view near the end of the arc tube as viewed in a plane including the lamp axis of the low pressure mercury lamp in a vertical relationship with the cut surface of FIG. 3C. FIG. 4A is a schematic view for explaining the state of the light emitting tube in which the amalgam is fixed by using the concave portion of the light emitting tube and the metal press of the electrode mount. FIG. 4B is a schematic view of the concave portion of the light emitting tube as viewed from directly above. FIG. 4C is a schematic view as seen from directly above the state in which the amalgam that has entered the recess of the light emitting tube is fixed using the metal press of the electrode mount. FIG. 5 is a flow chart for explaining the method for fixing the amalgam according to this embodiment among the methods for manufacturing a low pressure mercury lamp.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention according to the present invention will be described in detail with reference to the accompanying drawings with respect to embodiments of a low pressure mercury lamp and a method of manufacturing the same. In the figure, the same reference numerals are given to the same elements, and duplicate explanations are omitted.

Low pressure mercury lamp
(Structure of low pressure mercury lamp)
FIG. 2A is a view showing a low pressure mercury lamp 8. The luminous tube 8-1 of the low pressure mercury lamp 8 is formed of quartz glass. An amalgam is enclosed in the inside of the luminous tube 8-1. Amalgam is an alloy containing, in addition to mercury Hg, at least one metal of indium In, bismuth Bi, tin Sn, and lead Pb. In general, the proportion of the other metals is less than 5% by weight with respect to mercury Hg.

  In addition, although the light emitting tube shown to FIG. 2A is a straight tube | pipe type, it is not limited to this. The present embodiment is also applicable to arc tubes of other shapes such as U-shaped, W-shaped and M-shaped because the structure of the electrode portion is the same.

  The low pressure mercury lamp 8 is provided with bases (bases) 12-1 and 12-2 at both ends of the light emitting tube 8-1, and the light emitting tube in which the bases 12-1 and 12-2 are the coldest parts of the light emitting tube. Covering the end. The bases 12-1 and 12-2 fix the light emitting tube 8-1 and are a cover for preventing breakage of the end of the light emitting tube. The bases 12-1 and 12-2 are formed of a ceramic, a metal, and an elastic resin having resistance to ultraviolet light (for example, a fluorine resin).

(Structure in which the low pressure mercury lamp is positioned and held in the water cooling jacket)
FIG. 2B is a view for explaining the structure in which the low pressure mercury lamp is positioned and held at a predetermined position in the water cooling jacket. Here, (A) is a partial sectional view cut along the lamp axis near the lamp end, and (B) is a B-B sectional view.

  The light emitting tube 8-1 is disposed inside the water cooling jacket 6. The water cooling jacket 6 is provided for insulation between the lamp and the water to be treated and for lamp breakage protection, and is made of a member (for example, quartz glass) having ultraviolet transparency.

  The light emitting tube 8-1 is attached to the base 12-2 at one end. The base 12-2 is held at a predetermined position inside the water cooling jacket 6 by the base positioning and holding member 16. The opposite end of the lamp is of similar construction.

  As shown in FIG. 2B, the bases 12-1 and 12-2 support the arc tube 8-1 in contact with the water cooling jacket 6. Therefore, the coldest part of the arc tube 8-1 is both the temperature of the high temperature arc tube 8-1 at the time of lighting and the temperature of the low temperature base 12 in contact with the water cooling jacket 6 cooled with the water to be treated. to be influenced. The water temperature of the water to be treated is usually about 25 ° C.

  In general, the ultraviolet light output of the low pressure mercury lamp 8 depends on the vapor pressure of the amalgam in the arc tube when the lamp is lit. By controlling the temperature of the coldest portion of the luminous tube wall, the mercury vapor pressure inside the lamp can be controlled. By maintaining the coldest part of the arc tube wall at about 40 ° C. and maintaining the amalgam at about 80-120 ° C., the ultraviolet light output of wavelength 254 nm emitted from the low pressure mercury lamp 8 is maximized.

(Amalgam fixing means)
FIG. 3A is a side view of a single electrode mount with a metal hold down on one side. FIG. 3B is a front view of a single electrode mount with a metal hold down on one side. The low pressure mercury lamp 8 is AC driven, and the opposite end has the same electrode mount structure.

  The anode 22-1 is joined to the tip of the electrode lead wire 22 extending from the outside of the arc tube. In front of the anode 22-1, a filament 22-2 coated with an electron emitting material is bonded. The electrode lead wire 22 is held and held from both sides by a stay 24 formed of two glass members.

A metal presser 18 constituting a part of the electrode mount is attached to a first lead rod 18-1 formed of molybdenum Mo held by a glass stay 24 and the tip of the first lead A second lead rod 18-2 formed of nickel Ni, and a plate-like metal foil 18-3 at the tip of the second lead rod. A portion of the first lead rod 18-1 is bent in an L-shape and extends in the direction of the recess 20 formed in the light emitting tube 8-1. A second lead rod 18-2 is attached to the tip of the first lead rod 18-1, and a plate-like metal foil 18-3 is attached to the tip of the second lead rod. Reference numeral 3 covers at least a part of the recess 20 of the arc tube 8-1.
The metal foil 18-3 is formed of any of molybdenum Mo, tungsten W, nickel Ni, niobium Nb, and aluminum Al. The reasons for selecting these materials are as follows.
(1) A material that does not form amalgam with mercury
(2) A high melting point material that can withstand the heating and melting process of step 7 of the manufacturing method described later;
(3) A material having a certain elasticity and having a function of suppressing amalgam.

  Next, a state in which the electrode mount shown in FIGS. 3A and 3B is positioned in the arc tube and then the sealed amalgam is welded to the arc tube recess and the metal presser will be described. FIG. 3C is a partially cut view of the vicinity of the end of the light emitting tube as seen in a plane including the recess 20 of the light emitting tube 8-1 of the low pressure mercury lamp shown in FIG. 2A and including the lamp axis. FIG. 3D is a partial cutaway view of the vicinity of the end of the light emitting tube as viewed in a plane including the lamp axis of the low pressure mercury lamp 8 in a vertical relationship with the cut surface of FIG. 3C. In the vicinity of the end of the light emitting tube 8-1, a recess 20 is formed from the inner surface.

One specification of the embodiment of the low pressure mercury lamp 8 is as follows.
Lamp: straight tube type, lamp power 110 W, lamp current 1.38 A, lamp length (between base ends) 1,020 mm, lamp diameter φ 17 mm,
Recess shape: Rounded square with 5 mm length x 5 mm width x 1 mm depth squared first metal lead rod 18-1: φ 0.4 mm x 7 mm (total length)
Metal rebar second lead rod 18-2: φ 0.6 mm × 3 mm
Metal foil of metal press: Width 5 mm × thickness 35 μm × length 10 mm

  FIG. 4A is a schematic view illustrating the state of the light emitting tube 8-1 in which the amalgam 26 is fixed by using the concave portion 20 of the light emitting tube 8-1 and the metal presser 18 of the electrode mount. A recess 20 is formed on the inner surface of the quartz light emitting tube 8-1. The amalgam 26 is fixed to the inside of the recess 20 by using a metal retainer 18 and welded to both. Here, FIG. 4A (a) shows a state in which the metal presser 18 a covers about 1⁄3 of the opening area of the recess 20. In FIG. 4A (b), the metal retainer 18b covers about 2/3 of the opening area of the recess 20.

When covering about one third of FIG. 4A (a), the surface shape of the amalgam 26 is as shown by the reference numeral 26a. The amalgam 26 is welded to both the recess 20 and the metal retainer 18a. When covering about 2/3 of FIG. 4A (b), the surface shape of the amalgam 26 is as shown by the reference numeral 26b. The amalgam 26 is welded to both the recess 20 and the metal retainer 18b.
The difference between the surface shapes 26a and 26b is the variation due to the size of the contact area of the metal presser 18 with the recess.

  FIG. 4B is a schematic view of the recess 20 of the light emitting tube as viewed from directly above. The size of the recess 20 is typically a square with rounded corners of 5 mm long × 5 mm wide × 1 mm deep, but this size and shape are illustrative but not limited thereto.

  FIG. 4C is a schematic view as seen from directly above the state in which the amalgam 26 that has entered the recess 20 of the luminous tube is fixed using the recess 20 and the metal presser 18 of the electrode mount.

(Method of manufacturing low pressure mercury lamp)
FIG. 5 is a flow chart for explaining the method for fixing the amalgam according to this embodiment among the methods for manufacturing a low pressure mercury lamp.

In step S1, at the time of manufacture of the light emitting tube, concave portions are respectively formed in the coldest portion of the lamp near both ends. The concave portion is formed by pressing from the inside using a dedicated jig while heating from the outside of the arc tube.
In step S2, an electrode mount is formed. In the anode welding step of the electrode mount, a metal retainer is attached.
In step S3, the electrode mount is inserted into the light emitting tube, and the metal holder is positioned and fixed so as to cover the recess of the light emitting tube.
In step S4, the arc tube is pinch sealed.
In step S5, an additive including amalgam is enclosed in the luminous bulb via the exhaust pipe.
In step S6, the inside of the luminous bulb is exhausted via the exhaust pipe. After that, the exhaust pipe is chipped off and removed.
In step S7, the amalgam is positioned and fixed in the light emitting tube recess. While moving the lamp, move the amalgam into the arc tube recess and heat the arc tube recess from the outside in this state to melt the amalgam and weld it to the metal press of the electrode mount and the tube recess and fix it Let

[Summary]
As mentioned above, although the embodiment of the low pressure mercury lamp concerning the present invention and its manufacturing method was described, these are illustration for understanding the present invention, and do not limit the scope of the present invention at all. With respect to these embodiments, additions, deletions, modifications and improvements that can be easily made by those skilled in the art are within the scope of the present invention. The scope of the present invention is defined by the appended claims.

2: water supply port, 4: drainage port, 6: water cooling jacket, 8: low pressure mercury lamp, 8-1: arc tube, 10-1: horizontal water treatment tank, 10-2: vertical water treatment tank, 12, 12 -1, 12-2: base, 16: holding member, 18, 18a, 18b: metal presser, 18-1: first lead bar, 18-2: second lead bar, 18-3: metal foil 20: recessed portion 22: electrode lead wire 22-1: anode 22-4: filament 24: stay 26: amalgam 26a, 26b: amalgam surface

Claims (8)

In a method of manufacturing a low pressure mercury lamp,
Insert an electrode mount with a metal retainer into the arc tube,
Positioning the metal retainer in the vicinity of a recess formed on the inner surface of the light emitting tube;
Pinch sealing the end of the arc tube,
Amalgam is enclosed in the luminous bulb via an exhaust pipe,
Exhaust the luminous tube,
A method of manufacturing an amalgam, comprising a method of fixing the amalgam to the concave portion of the light emitting tube by heating and welding the amalgam to the metal press and the concave portion formed in the light emitting tube. In low pressure mercury lamps,
An arc tube in which a recess is formed on the inner surface near each end;
An electrode mount having a metal press and inserted into the luminous bulb;
And amalgam positioned in the recess.
The low-pressure mercury lamp, wherein the metal presser is arranged to cover at least a part of the amalgam. In the low pressure mercury lamp according to claim 2,
The low pressure mercury lamp, wherein the amalgam is positioned and fixed in the recess by heat welding. In the low pressure mercury lamp according to claim 2 or 3,
The low-pressure mercury lamp, wherein the metal holder comprises an elastic metal foil. In the low pressure mercury lamp according to claim 4,
The low-pressure mercury lamp, wherein the metal foil is formed of a metal selected from the group consisting of molybdenum Mo, tungsten W, nickel Ni, niobium Nb, and aluminum Al. In the low pressure mercury lamp according to claim 4 or 5,
The electrode mount has a stay made of glass,
The low-pressure mercury lamp, wherein the metal foil is attached to a lead rod held by the glass stay. In the low pressure mercury lamp according to claim 6,
A low pressure mercury lamp, wherein a part of the lead rod extends in the direction of a recess formed in the light emitting tube. In the low pressure mercury lamp according to claim 6 or 7,
The reed bar includes a first reed bar fixed to the glass stay and a second reed bar connected to the first reed bar.
The low-pressure mercury lamp, wherein the metal foil is attached to the tip of the second lead rod.

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