US4135053A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heating assembly for a heat treating furnace
Assignee: Ipsen International Inc
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Filing: 1977-12-23
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Granted: 1979-01-16
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Expires: 1997-12-23
Abstract
Abstract Graphite heating rods are disposed within a radiant tube which contains nitrogen under pressure to prevent oxidation of the rods. The pressure in the tube is sensed and nitrogen is admitted into or exhausted from the tube depending upon whether the pressure drops below or rises above a safe range. Only as much nitrogen is introduced into the tube as is necessary to replenish that which might be lost through normal leakage and thus only a comparatively small quantity of nitrogen is required to protect the graphite rods.
Inventors
- 👤 William W. Kastilahn
- 👤 Robert R. Garrett
- 👤 Vernon L. Park
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:18
CPC Classifications
F; F27; F27D; F27D11/00; F27D11/02; H; H05; H05B; H05B3/00; H05B3/62; H05B3/64
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
85 words
A heating assembly comprising a closed tube, an electrical resistance heating element disposed in said tube, means for admitting a flow of protective gas into said tube and for exhausting a flow of said gas out of said tube, and means for sensing the pressure of the gas in said tube and for causing gas to be admitted into said tube when said pressure is below a predetermined range and to be exhausted out of said tube when said pressure is above said predetermined range.
Claim 2
Dependent Claim
85 words
A heating assembly comprising a closed tube, an electrical resistance heating element disposed in said tube, means for admitting a flow of protective gas into said tube and for exhausting a flow of said gas out of said tube, and means for sensing the pressure of the gas in said tube and for causing gas to be admitted into said tube when said pressure is below a predetermined range and to be exhausted out of said tube when said pressure is above said predetermined range.
Claim 3
Dependent Claim
27 words
A heating assembly as defined in claim 1 further including means for producing a warning signal if said pressure remains below said range beyond a predetermined time.
Claim 4
Dependent Claim
27 words
A heating assembly as defined in claim 1 further including means for producing a warning signal if said pressure remains above said range beyond a predetermined time.
Claim 5
Dependent Claim
49 words
A heating assembly as defined in claim 1 further including means for producing a first warning signal if said pressure remains below said range beyond a predetermined time, and means for producing a second and distinctive warning signal if said pressure remains above said range beyond a predetermined time.
Claim 6
Dependent Claim
163 words
A heating assembly comprising a closed tube, an electrical resistance heating element disposed in said tube, a source of protective gas, an inlet valve which is operable when opened to admit gas from said source into said tube and which is operable when closed to cut off the flow of gas from said source to said tube, an exhaust valve which is operable when opened to vent gas out of said tube and which is operable when closed to cut off the flow of gas out of said tube, and means for sensing the pressure in said tube and for causing said inlet valve to be opened and said exhaust valve to be closed when said pressure is below a predetermined range, for causing said inlet valve to be closed and said exhaust valve to be opened when said pressure is above said predetermined range and for causing both of said valves to be closed when said pressure is within said predetermined range.
Claim 7
Dependent Claim
163 words
A heating assembly comprising a closed tube, an electrical resistance heating element disposed in said tube, a source of protective gas, an inlet valve which is operable when opened to admit gas from said source into said tube and which is operable when closed to cut off the flow of gas from said source to said tube, an exhaust valve which is operable when opened to vent gas out of said tube and which is operable when closed to cut off the flow of gas out of said tube, and means for sensing the pressure in said tube and for causing said inlet valve to be opened and said exhaust valve to be closed when said pressure is below a predetermined range, for causing said inlet valve to be closed and said exhaust valve to be opened when said pressure is above said predetermined range and for causing both of said valves to be closed when said pressure is within said predetermined range.
References Cited (Backward Citations)
US2320172A
Cited
US3053919A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-01-15 | 1982-07-17 | 1983-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-15 | 1986-07-17 | 1987-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-15 | 1990-07-17 | 1991-01-16 | $7700.00 | Window Closed / Lapsed |