Electric lamp having an envelope with an intermediate zirconium oxide coated layer
AssigneeU.S. Philips Corporation
InventorsLeo F. M. Ooms, Victor R. Notelteirs
Life of this patent
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Abstract
An electric lamp having a glass lamp vessel 1 with a seal 7 coated with an intermediate coating layer of zirconium oxide 8. Lamp vessel 1 is connected at its seal 7 by a sealing cement 9 to a lamp cap 2. Zirconium oxide coating 8 completely separates seal 7 from sealing cement 9 and reduces mutual adherence therebetween. During operation of the lamp, zirconium oxide coating 8 reduces the thermal load and prevents cracking of seal 7 of lamp vessel 1.
Claims18
An electric lamp comprising a lamp vessel of glass having a silica content of at least 95% by weight, which is sealed in a vacuum-tight manner and has a sealed end portion through which a current supply conductor extends to a lighting source arranged inside the lamp vessel, said current supply conductor being connected to a contact on a lamp cap fixed by a cementing substance disposed around a given area of the sealed end portion of the lamp vessel, characterized by comprising means for reducing adhesion of the cementing substance to said glass while substantially maintaining anchoring of the end portion in the lamp cap, said means comprising an intermediate coating applied to said glass at said area at which it is surrounded by the cementing substance.
An electric lamp comprising:
- a lighting source;
- a lamp vessel of glass having a silica content of at least 95% by weight, having said lighting source arranged therein and being sealed in a vacuum-tight manner, said lamp vessel having at least one sealed end portion;
- a plurality of current supply conductors, each of said current supply conductors extending through one of said at least one sealed end portion and electrically connected to said lighting source;
- at least one lamp cap having at least one electrical contact, each of said current supply conductors being connected to a respective one of said at least one contact of said at least one lamp cap, each of said at least one sealed end portion of said lamp vessel being disposed in a respective one of said at least one lamp cap, and
- a cementing substance disposed around a given area of said at least one sealed end portion, and securing each of said at least one sealed end portion of said lamp vessel in a respective one of said at least one lamp cap;
- and
- an intermediate coating layer applied to said glass of said at least one sealed end portion at said given area at which it is surrounded by said cementing substance, said coating layer completely separating said at least one sealed end portion from said cementing substance, said coating layer causing a reduced adherence between said cementing substance and said given area of said at least one sealed end portion, which is less than an adherence between said cementing substance and said given area of said at least one sealed portion in the absence of said intermediate coating layer.
An electric lamp comprising:
- a lighting source;
- a lamp vessel of glass having a silica content of at least 95% by weight, having said lighting source arranged therein and being sealed in a vacuum-tight manner, said lamp vessel having a sealed end portion;
- a plurality of current supply conductors, each of said current supply conductors extending through said sealed end portion and electrically connected to said lighting source;
- a lamp cap having a plurality of electrical contacts, each of said current supply conductors being connected to a respective one of said contacts of said lamp cap, said sealed end portion being disposed in said lamp cap, and
- a cementing substance disposed around a given area of said sealed end portion, and tightly surrounding and rigidly anchoring said sealed end portion in said lamp cap;
- and
- an intermediate coating layer comprising zirconium oxide applied to said glass of said sealed end portion at said area at which it is surrounded by said cementing substance, said zirconium oxide completely separating said sealed end portion from said cementing substance, said zirconium oxide causing a reduced adherence between said cementing substance and said given area of said sealed end portion, which is less than an adherence between said cementing substance and said given area of said sealed portion in the absence of said zirconium oxide.
Dependencies are inferred from the claim text.