Liquid filament for incandescent lights

Patent metadata

Field	Value
Publication number	US-9723702-B2
Application number	US-201615299401-A
Country	US
Kind code	B2
Filing date	Oct 20, 2016
Priority date	Aug 29, 2014
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A filament for a light bulb includes a tube and a filament material within the tube, wherein the filament material is configured to be in a liquid state while the light bulb is in use.

First claim

What is claimed is:

1. A method of generating light, comprising:
providing energy to a filament material via a supply wire; and
causing, from the energy, the filament material to achieve a liquid state, the filament material being contained in a tube;
wherein the tube is in a bulb containing a gas configured to counteract evaporation of at least one of the tube and the filament material.

2. The method of claim 1 , wherein the filament material is electrically conductive while in the liquid state.

3. The method of claim 1 , wherein the tube is thicker at each end than at a location between the two ends.

4. The method of claim 1 , wherein a first outer surface of the tube and a second outer surface of the tube are configured such that a temperature of the tube is lower at each end of the tube than at a location between the two ends.

5. The method of claim 1 , wherein a first thickness and outer diameter of the tube and a second thickness and outer diameter of the tube are configured such that a stress on the tube is lower at each end of the tube than at a location between the two ends.

6. The method of claim 1 , wherein the tube includes a cap having a thickness configured to at least one of (a) reduce a stress of the tube at at least one of the ends of the tube, (b) reduce the temperature of the tube at at least one of the ends of the tube, or (c) reduce the temperature of the supply wire.

7. The method of claim 1 , wherein the filament material includes at least one of tungsten, hafnium, or rhenium.

8. The method of claim 1 , wherein the filament has a designed emissivity, and wherein the designed emissivity is relatively high in the visible wavelengths and relatively low in at least one of ultraviolet wavelengths and infrared wavelengths.

9. The method of claim 1 , wherein the gas includes at least one of nitrogen gas, a nitrogen donating gas, or a carbon donating gas.

10. The method of claim 1 , wherein the tube is in a bulb containing a liquid.

11. The method of claim 10 , wherein the liquid at least one of affects one or more properties of the light emitted, cools the tube, and cools the filament material.

12. The method of claim 1 , further comprising:
ceasing to provide energy to the filament material; and
causing, from a lack of energy, the filament material to achieve a solid state, the filament material being contained in the tube.

13. A method for generating incandescent light using a filament material that melts when in use, comprising:
providing energy to the filament material via a supply wire;
controlling the amount of energy provided to the filament material using a control circuit; and
causing, from the energy, the filament material to achieve a liquid state, the filament material being contained in a tube;
wherein the tube includes a cap having a thickness configured to at least one of (a) reduce a stress of the tube at at least one of the ends of the tube, (b) reduce the temperature of the tube at at least one of the ends of the tube, or (c) reduce the temperature of the supply wire.

14. The method of claim 13 , wherein the filament material is electrically conductive while in the liquid state.

15. The method of claim 13 , wherein the tube is a highly refractory material.

16. The method of claim 13 , wherein the filament material includes a metal.

17. The method of claim 13 , wherein the filament material has a designed emissivity, and wherein the designed emissivity is relatively high in the visible wavelengths and relatively low in at least one of ultraviolet wavelengths and infrared wavelengths.

18. The method of claim 13 , wherein an emissivity of the filament material is controlled by the control circuit.

19. The method of claim 18 , wherein the control circuit is configured to control the emissivity of the filament material by controlling the amount of energy provided to the filament material.

20. The method of claim 13 , wherein the tube is in a bulb containing a vacuum.

21. The method of claim 13 , further comprising:
ceasing, through control by the control circuit, to provide energy to the filament material; and
causing, from a lack of energy, the filament material to achieve a solid state, the filament material being contained in the tube.

22. A method, comprising:
generating light using a filament material contained in a container, wherein the filament material is a solid material that changes into a liquid state when provided with energy from a supply wire;
wherein the container contains an inert gas.

23. The method of claim 22 , wherein the container is in a bulb containing a liquid.

24. The method of claim 22 , wherein the inert gas includes at least one of argon, nitrogen, and helium.

25. The method of claim 22 , wherein the container is a tube.

26. The method of claim 22 , further comprising ceasing to provide energy to the filament material; and
causing, from a lack of energy, the filament material to achieve a solid state, the filament material being contained in the container.

27. The method of claim 22 , wherein the filament material is configured to incandesce.

28. A method, comprising:
generating light using a filament material contained in a container, wherein the filament material is a solid material that changes into a liquid state when provided with energy from a supply wire;
wherein energy radiated by the filament material is absorbed by the container.

29. The method of claim 28 , wherein the container radiates visible light in response to absorbing the energy radiated by the filament material.

30. The method of claim 28 , wherein the container is opaque to at least a portion of the energy radiated by the filament material.

31. The method of claim 22 , wherein an inner surface of the container comprises a microstructure configured as a nucleation site for re-solidification of the filament material.

32. The method of claim 1 , wherein the tube includes at least one of hafnium carbide, hafnium nitride, or tantalum 4 hafnium carbide 5.

Assignees

• Elwha Llc

Inventors

• Hyde Roderick A
• Kare Jordin T
• Tuckerman David B
• Weaver Thomas A
• Wood Jr Lowell L
• Zare Richard N

Classifications

• H01K1/58

  Cooling arrangements · CPC title

• H01K1/10

  Bodies of metal or carbon combined with other substance · CPC title

• H01K1/50

  Selection of substances for gas fillings; Specified pressure thereof · CPC title

• H01K1/28

  Envelopes; Vessels · CPC title

• H01K1/62

  One or more circuit elements structurally associated with the lamp · CPC title