US3831004A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric heater
Assignee: FAST HEAT ELEMENT Manufacturing Co
•
Filing: 1973-07-27
•
Granted: 1974-08-20
•
Expires: 1993-07-27
Abstract
Abstract A cartridge or band heater having an internally threaded bushing secured thereof affording a secure mounting for electric wires or a conduit containing such wires.
Inventors
- 👤 R Wallstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:27
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/40; H05B3/54; H05B3/56; H05B3/02; H05B3/06; H05B3/565
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
106 words
An electric heater having flexible lead-in wires extending therefrom and an electrical heating element, a metal housing for said element, electrical insulation for said element and wires, and a metal bushing and clamp assembly, said assembly comprising an internally threaded metal bushing fixedly secured at one of its ends to one end of said metal housing and through which said lead-in wires extend, electrically insulated flexible current supply wires electrically connected to said lead-in wires, and an externally threaded rigid clamp fitting through which said supply wires extend, said clamp fitting being screw threaded into said bushing, said supply wires being secured to said clamp fitting.
Claim 2
Dependent Claim
106 words
An electric heater having flexible lead-in wires extending therefrom and an electrical heating element, a metal housing for said element, electrical insulation for said element and wires, and a metal bushing and clamp assembly, said assembly comprising an internally threaded metal bushing fixedly secured at one of its ends to one end of said metal housing and through which said lead-in wires extend, electrically insulated flexible current supply wires electrically connected to said lead-in wires, and an externally threaded rigid clamp fitting through which said supply wires extend, said clamp fitting being screw threaded into said bushing, said supply wires being secured to said clamp fitting.
Claim 3
Dependent Claim
13 words
The heater recited in claim 1, in which the heater is a cartridge.
Claim 4
Dependent Claim
18 words
The heater recited in claim 1, in which the wire connections are enclosed within the bushing and fitting.
Claim 5
Dependent Claim
29 words
The heater recited in claim 1, in which the heater is a band and the bushing is brazed to the outside surface of the band and projects radially therefrom.
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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) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |