LAMP ELECTRODE AND METHOD FOR DELIVERING MERCURY

Abstract

A lamp electrode adapted to deliver mercury during an assembly process has a supporting electrical lead attached to the proximal end of a metallic shell. The proximal and a distal ends of the metallic shell each lie along a central axis. A container with a vitreous plug in a sealed end contains a substance for delivering mercury upon heating of the container. The sidewall of the container is attached to the electrical lead. The longitudinal axis of the container is skewed relative to the electrical lead to orient the container in a direction to reduce discharge of mercury directly toward the metallic shell. The container is heated to open it and discharge a mercury dose from the sealed end, which is prone to opening upon heating of the container.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above brief description as well as other objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side view of a container in accordance with principles of the present invention;

FIG. 2 is an exploded, cross-sectional view of the container of FIG. 1;

FIG. 3 is a side view of a lamp electrode in accordance with principles of the present invention and employing the container of FIG. 1;

FIG. 4 is a detailed side view of a fragment of the shell, lead, and container of FIG. 3;

FIG. 5 is a side view taken along line 5-5 of FIG. 4;

FIG. 6 is a schematic diagram of a mechanism for sealing the container of FIG. 1;

FIG. 7 is an apparatus for welding containers of the type shown in FIG. 1 to a lead of the type shown in FIG. 3;

FIG. 8 is a side view of an implement shown in FIG. 7;

FIG. 9 is a side view of a lamp electrode that is an alternate to that of FIG. 3;

FIG. 10 is a fragmentary side view taken along line X-X of FIG. 9;

FIG. 11 is a side view of a portion of an electrode that is an alternate to that of FIG. 10;

FIG. 12 is a side view taken along line XII-XII of FIG. 11;

FIG. 13 is a side view of a portion of an electrode that is an alternate 10 to that of FIGS. 10 and 11;

FIG. 14 is a side view of a portion of an electrode that is an alternate to those previously illustrated;

FIG. 15 is a side view of a portion of an electrode that is an alternate to those previously illustrated; and

FIG. 16 is a side view of a portion of an electrode that is an alternate to those previously illustrated.

Claims

1. A lamp electrode adapted to deliver mercury during an assembly process, comprising: an electrode subassembly including:(a) a metallic shell having a proximal end and a distal end each lying along a central axis,(b) a supporting electrical lead attached to the proximal end of said metallic shell, and(c) a vitreous tube fused onto said electrical lead to surround said shell; anda container having a sidewall, a sealed end, and a longitudinal axis, said container containing a substance for delivering mercury upon heating of said container, said container being attached to said electrode subassembly and spaced proximally from said metallic shell, the longitudinal axis of the container being skewed to avoid parallelism relative to said central axis in order to orient said container in a direction to reduce discharge of mercury directly toward said metallic shell.

2. A lamp electrode according to claim 1 wherein said sealed end is prone to opening upon heating of said container.

3. A lamp electrode according to claim 1 wherein said container is spaced proximally from said metallic shell by an offset distance in order to avoid premature mercury delivery from said container upon heating of said shell.

4. A lamp electrode according to claim 1 wherein the sidewall of said container is attached to said electrical lead.

5. A lamp electrode according to claim 1 wherein said electrode subassembly comprises a rod attached to said shell, said container being attached to said rod.

6. A lamp electrode according to claim 1 wherein said container contains in addition to the mercury delivering substance an inert gas.

7. A lamp electrode according to claim 1 wherein said container has opposite said sealed end an opposite end that is further from said shell than said sealed end, said sealed end being prone to opening upon heating of said container.

8. A lamp electrode according to claim 7 wherein said sealed end of said container is further from said central axis than the opposite end of said container.

9. A lamp electrode according to claim 7 wherein said longitudinal axis of said container intersects a plane transverse to the central axis at an acute angle of at most 85°.

10. A lamp electrode according to claim 1 wherein said container comprises: a cup; anda annular header with a flange sealingly attached to said cup, said cup having a mouth with an outwardly projecting lip and a domed bottom, said sidewall being shaped substantially cylindrically.

11. (canceled)

12. A lamp electrode adapted to deliver mercury during an assembly process, comprising: an electrode subassembly including:(a) a metallic shell having a proximal end and a distal end each lying along a central axis,(b) a supporting electrical lead attached to the proximal end of said metallic shell, and(c) a vitreous tube fused onto said electrical lead to surround said shell; anda container containing a substance for delivering mercury upon heating of said container, said container having a sealed end with a vitreous plug, said container being supported on said electrode subassembly.

13. A lamp electrode according to claim 12 wherein said sealed end is prone to opening upon heating of said container.

14. A lamp electrode according to claim 12 wherein said plug comprises lead-free glass that is prone to melting upon heating of said container.

15. A lamp electrode according to claim 12 wherein said plug comprises glass that is prone to one or more of melting, fracturing, or dislodging upon heating of said container.

16. A lamp electrode according to claim 12 wherein said plug is color coded to indicate the quantity of mercury delivering substance in said container.

17. A lamp electrode according to claim 12 wherein said container has a metallic cup that is attached to said electrical lead.

18. A lamp electrode according to claim 12 wherein said electrode subassembly comprises a rod attached to said shell, said container being attached to said rod.

19. A lamp electrode according to claim 12 wherein said container has opposite said vitreous plug an opposite end that is further from said shell than said sealed end.

20. A lamp electrode according to claim 12 wherein said container comprises: a cup and an annular header sealingly attached to said cup, said vitreous plug being centrally mounted in said header.

21. A lamp electrode according to claim 20 wherein said header has a flange, said cup having a mouth with an outwardly projecting lip and a domed bottoms, said sidewall being cylindrically shaped.

22-37. (canceled)