Sealed beam headlamp and method for testing its serviceability
AssigneeCooper Industries, Inc.
InventorRichard DuBois, Jr.
Life of this patent
Estimating the term…
Abstract
A sealed beam lamp having an outer envelope defining a gas-tight enclosure filled with an inert nonreactive gas at a pressure in the range of 5 to 50 Torrs, and an illuminating burner capsule mounted within the enclosure. The integrity of the gas-tight enclosure as well as the pressure of the gas is verified by creating a predetermined electrical potential within the enclosure to form a glow discharge in the gas if the gas pressure is within a predetermined range indicating the lamp is serviceable and an arc discharge if the gas pressure is in excess of the range indicating the lamp is defective.
Claims15
A sealed beam lamp, comprising:
- an envelope having an outer shell defining a gas-tight enclosure;
- an illuminating bulb having a lighting filament sealed within said bulb;
- bulb support means mounted on said outer shell for securing said illuminating bulb within said gas-tight enclosure;
- means for conducting electrical current coupled to said lighting filament and extending through said outer shell to selectively energize said lighting filament;
- said gas-tight enclosure being filled with a relatively nonreactive gas at a pressure in the range of 5 to 50 Torrs.
A sealed beam lamp, comprising:
- a gas-tight envelope having an outer shell;
- a burner capsule having a bulb enclosure and a lighting filament sealed within said bulb enclosure;
- a plurality of members for conducting electricity extending through said outer shell, said member for conducting electricity further including means for securing said bulb to at least one of said members for conducting electricity and for securing said bulb enclosure within said gas-tight envelope, said members for conducting electricity further being electrically coupled to said lighting filament for energizing said lighting filament;
- and
- said gas-tight envelope being filled with a relatively nonreactive gas at a pressure in the range of 5 to 50 Torrs.
In a process for manufacturing a sealed beam lamp including an envelope having an outer shell which defines a gas-tight enclosure having a sealable gas filling port opening into the enclosure through the outer shell, a burner capsule having a bulb enclosure and a lighting filament sealed within the bulb enclosure, bulb enclosure support means mounted on the outer shell for securing said bulb enclosure within the gas-tight enclosure, and circuit means connected with the lighting filament and extending through the outer shell to accommodate energization of the lighting filament when the sealed beam lamp is in use, the final assembly and inspection comprising the steps of;
- filling the gas-tight enclosure through the gas filling port with a relatively nonreactive gas at a pressure in the range of 5 to 50 Torrs;
- closing-off the gas filling port to seal and maintain the gas within the enclosure at 5 to 50 Torrs;
- and
- creating a predetermined electrical potential within the enclosure;
- whereupon, formation of a glow discharge in the gas indicates that the envelope is sealed and the gas pressure is within the range of 5 to 50 Torrs, and formation of an arc discharge indicates that the gas pressure is above 5 to 50 Torrs.
Dependencies are inferred from the claim text.