US4547659A
Expired / Lapsed
US
⏱️ 0.0 years remaining
PTC Heater assembly
Assignee: Raychem Corp
•
Filing: 1983-12-05
•
Granted: 1985-10-15
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Expires: 2003-12-05
Abstract
Abstract A PTC heater assembly comprises at least one PTC heater surrounded by an envelope of high thermal conductivity, thus greatly increasing the power output of the heater under operating conditions. In a preferred assembly a strip heater, comprising (i) an elongate strip of a conductive polymer PTC composition, (ii) electrodes embedded in said strip, and (iii) an insulating jacket, is sandwiched between a pair of metal, e.g. aluminum, sheets.
Inventors
- 👤 David F. Leary
- 👤 Alan Brigham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:42
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/40; H05B3/54; H05B3/56
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
109 words
A heater assembly which comprises (a) a PTC heater which has a passive power rating of 70 to 200 watts/foot and which comprises (i) an elongate strip of a conductive polymer PTC composition; (ii) two elongate, parallel electrodes in physical and electrical contact with said strip; and (iii) an electrically insulating jacket which surrounds said strip and said electrodes; and (b) an envelope which substantially surrounds and is in intimate thermal contact with said PTC heater, which is electrically insulated from said elongate strip and said electrodes by said insulating jacket, and which is composed of a material having a thermal conductivity of at least 0.3 Cal/cm. °C. sec.
Claim 2
Dependent Claim
109 words
A heater assembly which comprises (a) a PTC heater which has a passive power rating of 70 to 200 watts/foot and which comprises (i) an elongate strip of a conductive polymer PTC composition; (ii) two elongate, parallel electrodes in physical and electrical contact with said strip; and (iii) an electrically insulating jacket which surrounds said strip and said electrodes; and (b) an envelope which substantially surrounds and is in intimate thermal contact with said PTC heater, which is electrically insulated from said elongate strip and said electrodes by said insulating jacket, and which is composed of a material having a thermal conductivity of at least 0.3 Cal/cm. °C. sec.
Claim 3
Dependent Claim
39 words
A heater assembly according to claim 1 wherein said heater assembly has an active power output at 50° F. which is at least 1.5 times the active power output at 50° F. of the PTC heater without the envelope.
Claim 4
Dependent Claim
15 words
A heater assembly according to claim 1 wherein said envelope is composed of a metal.
Claim 5
Dependent Claim
12 words
A heater assembly according to claim 3 wherein said metal is aluminum.
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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) | 1988-10-14 | 1989-04-15 | 1989-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-14 | 1993-04-15 | 1993-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-14 | 1997-04-15 | 1997-10-15 | $7700.00 | Window Closed / Lapsed |