Patent US3694628A successfully refreshed from Google Patents.
US3694628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible heating unit with separately replaceable heating elements
Assignee: IND HEATER CO Inc
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Filing: 1971-12-14
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Granted: 1972-09-26
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Expires: 1991-12-14
Abstract
Abstract An elongated flexible heating unit for spiral wrapping around items to be annealed or heat treated contains a plurality of heating elements in parallel circuit so that a heat treating cycle may be carried to completion even if there should be failure of an individual heating element. Novel junction boxes at opposed ends of the heating unit facilitate both easy coupling to available sources of electrical power and easy replacement of individual heating elements. Articulating spacer and protective elements longitudinally of the unit are of heat conducting ceramic material throughout the major portion of the length of the unit and of heat insulating ceramic in the lead portions adjacent the junction boxes.
Inventors
- 👤 Thomas A Mcgwire
- 👤 Emilio A Racinez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:08
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/40; H05B3/54; H05B3/56; H05B3/02; H05B3/06; H05B3/565
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
118 words
A heating unit of elongated flexible structure adapted for spiral wrapping around weld zones and structures to be heat treated, said heating unit comprising a plurality of juxtaposed ceramic bodies having aligned apertures receiving at least three closely spaced parallel flexible heating elements, abutting surfaces of said ceramic bodies having interfitting curvatures providing great flexibility longitudinally of the unit, said heating elements terminating in electrically insulating junction boxes at opposed ends of said unit, said junction boxes having adjustable means for individually and detachably coupling said heating elements therewith, and each of said junction boxes including other adjustable means for detachably joining electrical leads from one pole of a power source with said heating elements in parallel circuit.
Claim 2
Dependent Claim
118 words
A heating unit of elongated flexible structure adapted for spiral wrapping around weld zones and structures to be heat treated, said heating unit comprising a plurality of juxtaposed ceramic bodies having aligned apertures receiving at least three closely spaced parallel flexible heating elements, abutting surfaces of said ceramic bodies having interfitting curvatures providing great flexibility longitudinally of the unit, said heating elements terminating in electrically insulating junction boxes at opposed ends of said unit, said junction boxes having adjustable means for individually and detachably coupling said heating elements therewith, and each of said junction boxes including other adjustable means for detachably joining electrical leads from one pole of a power source with said heating elements in parallel circuit.
Claim 3
Dependent Claim
53 words
A heating unit as defined in claim 1, wherein the ceramic bodies throughout the major portion of the length of said unit have high heat conducting properties, while ceramic bodies in end portions of said unit adjacent the junction boxes have heat insulating properties, and said junction boxes are of heat insulating material.
Claim 4
Dependent Claim
48 words
A heating unit as defined in claim 2, wherein the heat insulating ceramic bodies adjacent said junction boxes are of cylindrical bead-like structure receiving individual heating elements, thereby facilItating attachment and detachment of individual heating elements without disturbing the coupling of other heating elements with said junction boxes.
Claim 5
Dependent Claim
105 words
A heating unit as defined in claim 1, wherein said junction boxes each comprise a block of heat insulating material having a plurality of parallel electrically conductive metal tubes extending therethrough, one face of said block having a plurality of recesses extending perpendicularly to and spaced longitudinally of each of said tubes, each of said tubes having a plurality of threaded apertures coaxial with said recesses, and threaded anchoring means in each of said apertures with the actuating heads thereof exposed at but embedded in said recesses providing the means for individually and detachably securing said heating elements and power leads to said junction box.
Claim 6
Dependent Claim
30 words
A heating unit as defined in claim 4, wherein said electrically conductive metal tubes are of sufficient inner diameter to receive overlapped portions of said heating elements and power leads.
Claim 7
Dependent Claim
49 words
A heating unit as defined in claim 5, wherein there are at least three threaded apertures and anchoring means for each of said tubes with at least one of said apertures and anchoring means being positioned to register with overlapped portions of the engaged heating element and power lead.
Claim 8
Dependent Claim
111 words
A heating unit as defined in claim 1, wherein the ceramic bodies throughout the major heating portion of said unit are of substantially uniform dimension in two directions and much elongated in a third direction, with uniformly spaced apertures extending through one of the short dimensions thereof, opposed apertured surfaces of said bodies having corresponding concave and convex curvature throughout the length thereof permitting relative sliding movement between juxtaposed ceramic bodies to vary the common plane of said apertures in adjacent bodies, and between the heating portion of said unit and said junction boxes individual heating elements are enveloped by a series of bead-like cylindrical bodies of heat insulating ceramic material.
Claim 9
Dependent Claim
26 words
A heating unit as defined in claim 7, wherein opposed surfaces of said elongated ceramic bodies paralleling the apertures therein are substantially parallel to each other.
Claim 10
Dependent Claim
49 words
A heating unit as defined in claim 8, wherein said last named surfaces at at least one side of said unit have a slightly concave curvature extending throughout the length thereof providing increased surface contact in the spiral wrapping of said unit around cylindrical structures to be heat treated.
Claim 11
Dependent Claim
62 words
A heating unit as defined in claim 1, wherein flexibility of said unit permits spiral wrapping with either of the opposed elongated surfaces thereof in engagement with a structure to be heat treated, and surfaces of said ceramic bodies on at least one side of said unit being specially contoured to provide enhanced surface contact with particular structures to be heat treated.
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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) | 1975-09-26 | 1976-03-27 | 1976-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-26 | 1980-03-27 | 1980-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-26 | 1984-03-27 | 1984-09-26 | $7700.00 | Window Closed / Lapsed |