US3877518A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchange coil
Assignee: MARSHALL INDUSTRIES Inc
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Filing: 1971-03-19
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Granted: 1975-04-15
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Expires: 1991-03-19
Abstract
Abstract Aluminum tubes particularly useful in forming heat exchange coils are joined together by first flaring and necking respective tube ends to define tapered mating surfaces to insure maximum wetting of both surfaces by the epoxy which bonds the tubes together when the epoxy coated male tube is inserted axially within the female tube.
Inventors
- 👤 Moshe Y Dreksler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:13
CPC Classifications
F; F16; F16B; F16B11/00; F16B11/006; F16B11/008; B; B21; B21D; B21D39/00; B21D39/04; B21D53/00; B21D53/02; B21D53/08; B21D53/085; F16L; F16L13/00; F16L13/10; F16L13/103; F28; F28F; F28F9/00; F28F9/26; F28F2275/00; F28F2275/02; F28F2275/025; Y; Y10; Y10S; Y10S165/00; Y10S165/454; Y10S165/495; Y10S285/00; Y10S285/915
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
175 words
In a heat exchange coil of the type including a plurality of adjacently positioned first hairpin shaped aluminum tubes carrying internally, a high pressure fluid, and being commonly supported by a plurality of longitudinally spaced heat exchange fins with the straight portions of said tubes exteNding through holes within the fins and with the ends of two separate tubes being joined by a second, U-shaped return bend aluminum tube, the improvement wherein: the ends of one of said tubes are flared and the ends of said other tubes are necked to define axially opposed tapered mating surfaces, and wherein said tubes are coupled together solely by a uniform thickness epoxy adhesive between said mating surfaces to complete a high integrity, fluid seal bond therebetween of sufficient strength to prevent longitudinal separation of the return bend tube from the straight portions of the tubes joined thereto due to the high fluid pressure acting directly on said return bend tube and creating a resultant force tending to longitudinally separate the return bend tube from said hairpin tubes.
Claim 2
Dependent Claim
175 words
In a heat exchange coil of the type including a plurality of adjacently positioned first hairpin shaped aluminum tubes carrying internally, a high pressure fluid, and being commonly supported by a plurality of longitudinally spaced heat exchange fins with the straight portions of said tubes exteNding through holes within the fins and with the ends of two separate tubes being joined by a second, U-shaped return bend aluminum tube, the improvement wherein: the ends of one of said tubes are flared and the ends of said other tubes are necked to define axially opposed tapered mating surfaces, and wherein said tubes are coupled together solely by a uniform thickness epoxy adhesive between said mating surfaces to complete a high integrity, fluid seal bond therebetween of sufficient strength to prevent longitudinal separation of the return bend tube from the straight portions of the tubes joined thereto due to the high fluid pressure acting directly on said return bend tube and creating a resultant force tending to longitudinally separate the return bend tube from said hairpin tubes.
Claim 3
Dependent Claim
80 words
The heat exchange coil as claimed in claim 1, wherein said first tubes are two in number and are coupled together by a second return bend tube and wherein said heat exchange coil further includes threaded aluminum tubular fittings having complementary tapered mating surfaces epoxy bonded to the outside ends of said respective first tubes in identical fashion to that of said return bend tube and acting as the sole means for coupling said fittings to said said first tubes.
Claim 4
Dependent Claim
108 words
The heat exchange coil assembly as claimed in claim 1, wherein said first tubes terminate in male neck portions defining inwardly tapered mating surfaces and said second return bend tube terminates in flared portions defining corresponding outwardly tapering mating surfaces and said assembly further includes threaded tubular aluminum fittings coupled to the outside ends of respective first tubes, said threaded tubular aluminum fittings each including an axially tapered bore which mates with a necked end of said first tube with a uniform thickness epoxy adhesive bonding the mating surfaces therebetween, and acts as the sole means for coupling said fittings to the outside ends of respective first tubes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |