US3857017A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Unitary thermal reference source
Assignee: DYNARAD
•
Filing: 1972-04-20
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Granted: 1974-12-24
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Expires: 1992-04-20
Abstract
Abstract A thermal reference source in which the interrelated functions of heater, radiator, and temperature sensor are provided by a unitary and integrally formed structure. The reference is formed of a homogeneous, temperature sensitive resistive material shaped to define a radiative cavity and includes terminals for connection to an associated control circuit. Temperature changes are sensed in a substantially instantaneous manner and rapid control easily maintained.
Inventors
- 👤 C Whittier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:44
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/20; G05D23/24; G05D23/2401; G01; G01J; G01J5/00; G01J5/52; G01J5/53; H; H05; H05B; H05B3/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
114 words
A thermal reference comprising: a generally hollow, cylindrical structure open at each end and formed of an electrically resistive material having a significantly non-zero resistance temperature coefficient; said cylindrical structure having an elbow curve in a portion thereof whereby an interior surface of said structure occludes the view through said cylindrical structure from end to end; first and second terminals on said structure at said ends for receiving electrical current; means for applying electrical current to said structure at said first and second terminals to provide a distributed current through said structure; the flow of electrical current through said structure being directly operative to simultaneously affect the temperature, radiation, and resistance of said structure.
Claim 2
Dependent Claim
114 words
A thermal reference comprising: a generally hollow, cylindrical structure open at each end and formed of an electrically resistive material having a significantly non-zero resistance temperature coefficient; said cylindrical structure having an elbow curve in a portion thereof whereby an interior surface of said structure occludes the view through said cylindrical structure from end to end; first and second terminals on said structure at said ends for receiving electrical current; means for applying electrical current to said structure at said first and second terminals to provide a distributed current through said structure; the flow of electrical current through said structure being directly operative to simultaneously affect the temperature, radiation, and resistance of said structure.
Claim 3
Dependent Claim
38 words
The thermal reference of claim 1 further including: means for sensing the resistance of said structure between said terminals; and means for controlling the application of current to said structure to maintain a predetermined resistance for said material.
Claim 4
Dependent Claim
164 words
A unitary thermal reference source comprising: an elongated unitary structure open at at least one end and formed of an electrically resistive material having a non-zero resistance temperature coefficient and having a cavity therein terminating at said at least one open end in an aperture from which thermal energy is radiated; first and second electrical terminals affixed and in electrical contact with respective opposite ends of said elongated structure; and means for applying electrical current directly to said structure at said first and second electrical terminals to provide a distributed current flow through said structure; the flow of electrical current through said structure being directly operative to simultaneously affect the temperature, radiation and resistance of said structure; said means for applying electrical current to said terminals further including means for controlling the current applied to said first and second terminals in response to the resistance of said structure between said terminals and operative to maintain said resistance of said structure at a predetermined value.
Claim 5
Dependent Claim
164 words
A unitary thermal reference source comprising: an elongated unitary structure open at at least one end and formed of an electrically resistive material having a non-zero resistance temperature coefficient and having a cavity therein terminating at said at least one open end in an aperture from which thermal energy is radiated; first and second electrical terminals affixed and in electrical contact with respective opposite ends of said elongated structure; and means for applying electrical current directly to said structure at said first and second electrical terminals to provide a distributed current flow through said structure; the flow of electrical current through said structure being directly operative to simultaneously affect the temperature, radiation and resistance of said structure; said means for applying electrical current to said terminals further including means for controlling the current applied to said first and second terminals in response to the resistance of said structure between said terminals and operative to maintain said resistance of said structure at a predetermined value.
Claim 6
Dependent Claim
96 words
The thermal reference of claim 3 wherein said current controlling means further includes: a resistivE bridge having said structure as one leg thereof connected between said first and second terminals; means for applying electrical current to a first pair of opposite nodes of said bridge; means for sensing the potential difference between a second pair of opposite nodes of said bridge; and means responsive to the sensed potential difference for regulating the current applied to said first pair of opposite nodes of said bridge so as to maintain said sensed potential difference at a predetermined value.
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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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |