US3720826A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tubular electric discharge lamp with integral protective-insulating sleeve
Assignee: Philips North America LLC
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Filing: 1970-05-05
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Granted: 1973-03-13
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Expires: 1990-05-05
Abstract
Abstract A rigid open-ended sleeve of plastic or other light-transmitting material is suspended in telescoped spaced-apart relationship with the glass envelope of an electric lamp by slipping the sleeve over a pair of spaced rubber grommets that compressively grip the envelope. The grommets effect a force fit with the sleeve and the latter is retained in place on the lamp solely by the grommets. In the case of a fluorescent lamp or other type of low-pressure electric discharge lamp, the sleeve serves both as a protective shield against accidental breakage of the envelope and as an insulating jacket which permits the lamp to operate efficiently at low ambient temperatures (-18*C for example). The sleeve can be fabricated from colored plastic or glass to provide a low-cost fluorescent lighting unit that emits light of a selected color and is thus especially adapted for use in outdoor decorative lighting applications.
Inventors
- 👤 J Gilmore
- 👤 R Epting
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:16
CPC Classifications
F; F21; F21V; F21V29/00; F21V17/00; F21V17/04
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
222 words
A lighting unit comprising, in combination; an electric lamp having a tubular glass envelope, a protective shield for said envelope consisting of a rigid tubular open-ended sleeve of light-transmitting plastic that (a) is larger than and is suspended in spaced-apart telescoped relationship with said envelope, (b) is shorter than said lamp, and (c) expands and contracts to a greater degree than said glass envelope under varying ambient temperature conditions, and means retaining said plastic sleeve on the lamp in the aforesaid relationship with said envelope comprising a plurality of narrow band-like members of resilient material that encircle the envelope at spaced points along its length and are located between said envelope and sleeve, said retaining members being of such size that they compressively grip the encircled parts of the envelope and are in tight frictional engagement with the overlying encircling portions of said sleeve so that the sleeve is securely anchored in place on the lamp solely by said retaining members, the retaining members that are located at the ends of said lamp being disposed inwardly a predetermined distance from the respective ends of both the sleeve and envelope such that the plastic sleeve is free and able to expand and contract relative to the glass envelope under varying ambient temperature conditions without forcing the outermost retaining members off of said lamp.
Claim 2
Dependent Claim
222 words
A lighting unit comprising, in combination; an electric lamp having a tubular glass envelope, a protective shield for said envelope consisting of a rigid tubular open-ended sleeve of light-transmitting plastic that (a) is larger than and is suspended in spaced-apart telescoped relationship with said envelope, (b) is shorter than said lamp, and (c) expands and contracts to a greater degree than said glass envelope under varying ambient temperature conditions, and means retaining said plastic sleeve on the lamp in the aforesaid relationship with said envelope comprising a plurality of narrow band-like members of resilient material that encircle the envelope at spaced points along its length and are located between said envelope and sleeve, said retaining members being of such size that they compressively grip the encircled parts of the envelope and are in tight frictional engagement with the overlying encircling portions of said sleeve so that the sleeve is securely anchored in place on the lamp solely by said retaining members, the retaining members that are located at the ends of said lamp being disposed inwardly a predetermined distance from the respective ends of both the sleeve and envelope such that the plastic sleeve is free and able to expand and contract relative to the glass envelope under varying ambient temperature conditions without forcing the outermost retaining members off of said lamp.
Claim 3
Dependent Claim
222 words
A lighting unit comprising, in combination; an electric lamp having a tubular glass envelope, a protective shield for said envelope consisting of a rigid tubular open-ended sleeve of light-transmitting plastic that (a) is larger than and is suspended in spaced-apart telescoped relationship with said envelope, (b) is shorter than said lamp, and (c) expands and contracts to a greater degree than said glass envelope under varying ambient temperature conditions, and means retaining said plastic sleeve on the lamp in the aforesaid relationship with said envelope comprising a plurality of narrow band-like members of resilient material that encircle the envelope at spaced points along its length and are located between said envelope and sleeve, said retaining members being of such size that they compressively grip the encircled parts of the envelope and are in tight frictional engagement with the overlying encircling portions of said sleeve so that the sleeve is securely anchored in place on the lamp solely by said retaining members, the retaining members that are located at the ends of said lamp being disposed inwardly a predetermined distance from the respective ends of both the sleeve and envelope such that the plastic sleeve is free and able to expand and contract relative to the glass envelope under varying ambient temperature conditions without forcing the outermost retaining members off of said lamp.
Claim 4
Dependent Claim
222 words
A lighting unit comprising, in combination; an electric lamp having a tubular glass envelope, a protective shield for said envelope consisting of a rigid tubular open-ended sleeve of light-transmitting plastic that (a) is larger than and is suspended in spaced-apart telescoped relationship with said envelope, (b) is shorter than said lamp, and (c) expands and contracts to a greater degree than said glass envelope under varying ambient temperature conditions, and means retaining said plastic sleeve on the lamp in the aforesaid relationship with said envelope comprising a plurality of narrow band-like members of resilient material that encircle the envelope at spaced points along its length and are located between said envelope and sleeve, said retaining members being of such size that they compressively grip the encircled parts of the envelope and are in tight frictional engagement with the overlying encircling portions of said sleeve so that the sleeve is securely anchored in place on the lamp solely by said retaining members, the retaining members that are located at the ends of said lamp being disposed inwardly a predetermined distance from the respective ends of both the sleeve and envelope such that the plastic sleeve is free and able to expand and contract relative to the glass envelope under varying ambient temperature conditions without forcing the outermost retaining members off of said lamp.
Claim 5
Dependent Claim
130 words
The combination of claim 1 wherein; said electric lamp comprises a fluorescent lamp that contains an ionizable medium and a pair of spaced electrodes which are connected to terminals that are located at and protrude beyond the respective ends of the lamp envelope and are anchored in base members fastened to the ends of said envelope, said open-ended plastic sleeve is of substantially the same length as the envelope and is so positioned that said base members and terminals are exposed, said retaining members comprise rubber grommets that are spAced inwardly from the respective base members, and the distance the outermost grommets are spaced inwardly from the respective ends of the sleeve and base members is correlated with the length of the lamp and increases as the lamp length increases.
Claim 6
Dependent Claim
24 words
The combination of claim 2 wherein; said open-ended sleeve is composed of polycarbonate resin, and said rubber grommets are of substantially uniform wall thickness.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |