US4530520A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically weldable bushings
Assignee: WAVIN AG
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Filing: 1984-03-08
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Granted: 1985-07-23
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Expires: 2004-03-08
Abstract
Abstract A bushing for joining the ends of fluid line conduits, or similar elements, comprising a body of thermoplastic, in which is embedded, in helical form, a resistance wire. The wire has a low coefficient of thermal expansion, permitting the thermoplastic material to melt and weld prior to the expansion thereof.
Inventors
- 👤 Heniz Nyffeler
- 👤 Rudolf Buri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:09
CPC Classifications
B; B29; B29C; B29C65/00; B29C65/02; B29C65/34; B29C65/3404; B29C65/342; B29C65/3472; B29C65/3476; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/114; B29C66/1142; B29C66/50; B29C66/51; B29C66/52; B29C66/522; B29C66/5221; B29C66/5229; B29C66/70; B29C66/73; B29C66/739; B29C66/7392; B29C66/73921; F; F16; F16L; F16L47/00; F16L47/02; F16L47/03; B29C65/3468
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
40 words
An electrically weldable bushing for connecting conduit line elements comprising a body formed of thermoplastic material, having filament wire embedded therein, said filament wire comprising a nickel-iron alloy having a coefficient of thermal expansion of less than 10×10 -6 /°C.
Claim 2
Dependent Claim
40 words
An electrically weldable bushing for connecting conduit line elements comprising a body formed of thermoplastic material, having filament wire embedded therein, said filament wire comprising a nickel-iron alloy having a coefficient of thermal expansion of less than 10×10 -6 /°C.
Claim 3
Dependent Claim
24 words
The bushing according to claim 1, characterized in that the filament wire has a coefficient of thermal expansion of less than 2.0×10 -6 /°C.
Claim 4
Dependent Claim
27 words
The bushing according to claim 2, wherein said body is cylindrical and said filament wire is embedded in a helical coil in proximity to the inner wall.
Claim 5
Dependent Claim
36 words
The bushing according to claim 3, wherein said bushing body is formed of two concentric parts, the inner part having a thread surface into which said wire is laid, and the outer part matingly conforming thereto.
Claim 6
Dependent Claim
17 words
The bushing according to claim 2, wherein said bushing body is integrally formed with a line element.
Claim 7
Dependent Claim
19 words
The bushing according to claim 1, characterized in that the filament wire has a negative coefficient of thermal expansion.
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) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |