US3678249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heater element
Assignee: ARC O VEC Inc
•
Filing: 1970-10-21
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Granted: 1972-07-18
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Expires: 1990-10-21
Abstract
Abstract An electrical resistance heater is disclosed in an elongated tubular form wherein at least one resistance heating unit is coiled within a tubular housing. The resistance heating units include a coiled metallic sheath containing an internally coiled resistance wire that is fixed in the sheath by a mass of magnesium oxide. The heating units are similarly fixed in the tubular housing. Heating units coiled with a variable pitch and plural heating units of different characteristics are disclosed to accomplish different heat zones within the apparatus.
Inventors
- 👤 Thomas H Lennox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:47
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/40; H05B3/42; H05B3/48
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
122 words
An electric heater, comprising: an elongated metallic outer housing tube means having one end closed; a plurality of resistance heating units helically coiled in axial alignment within said outer tube means and each including an elongated coiled metallic sheath means, a resistance wire coiled within said sheath means, and a first non-conductive inorganic mass disposed within said sheath means to support said resistance wire within said metallic sheath means, the resistor wire of each of said heating units having terminals extending through the open end of the housing tube means for connecting to appropriate sources of electrical energy; and a second non-conductive inorganic mass disposed within said outer tube means to support said resistance heating unit coiled within said outer tube means.
Claim 2
Dependent Claim
122 words
An electric heater, comprising: an elongated metallic outer housing tube means having one end closed; a plurality of resistance heating units helically coiled in axial alignment within said outer tube means and each including an elongated coiled metallic sheath means, a resistance wire coiled within said sheath means, and a first non-conductive inorganic mass disposed within said sheath means to support said resistance wire within said metallic sheath means, the resistor wire of each of said heating units having terminals extending through the open end of the housing tube means for connecting to appropriate sources of electrical energy; and a second non-conductive inorganic mass disposed within said outer tube means to support said resistance heating unit coiled within said outer tube means.
Claim 3
Dependent Claim
32 words
An electric heater according to Claim 1 wherein said resistance heating units are coiled to define differently spaced helical forms to provide a variation in heat along the length of said heater.
Claim 4
Dependent Claim
17 words
An electric heater according to Claim 1 wherein said resistance heating unit comprises a bifiler helical configuration.
Claim 5
Dependent Claim
17 words
An electric heater according to Claim 1 wherein said inorganic masses comprise mineral in fine particle form.
Claim 6
Dependent Claim
17 words
An electric heater according to Claim 1 wherein said inorganic masses comprise compacted particles of magnesium oxide.
Claim 7
Dependent Claim
21 words
An electrical heater according to claim 1 further including sensor means fixed within at least one of said resistance heating units.
Claim 8
Dependent Claim
27 words
An electric heater according to claim 1 wherein at least one of said resistance heating units comprises a bifilar helical configuration coiled within said outer tube means.
Claim 9
Dependent Claim
28 words
An electric heater according to claim 1 wherein at least one of said resistance heating units further includes linear lengths extending through another of said resistance heating units.
Claim 10
Dependent Claim
21 words
An electric heater according to claim 1 wherein said inorganic masses each comprise particles of magnesium oxide compacted into a mass.
Claim 11
Dependent Claim
27 words
An electric heater according to claim 1 wherein said terminals comprise cold connection leads extending through a non-conductive mass contiguous said open end of the housing tube.
Claim 12
Dependent Claim
22 words
An electric heater according to claim 1 wherein said sheath means comprises material selected from the metals stainless steel and nickel alloys.
References Cited (Backward Citations)
US1350910A
Cited
US1451880A
Cited
US2371696A
Cited
US2725457A
Cited
US3307017A
Cited
US3340382A
Cited
US3461275A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |