US3610592A
Expired / Lapsed
US
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Method and apparatus for estimating errors in pyrometer readings
Assignee: United States Steel Corp
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Filing: 1969-07-29
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Granted: 1971-10-05
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Expires: 1989-07-29
Abstract
Abstract Apparatus for and a method of determining the proper emittance factor for the combined thermal radiation from a body (disposed in a heating cavity defined by the walls of a furnace means and heated to a predetermined temperature by heating means associated with the furnace means) and the reflected thermal radiation from the walls to measure the temperature of the body with a minimum range of temperature error, are disclosed. The apparatus has sight tube means disposed in one of the walls and in registry with the body, and a body-temperature-measuring pyrometer having a high temperature to emittance factor ratio sensitivity disposed in the sight of tube means. The bodytemperature-measuring pyrometer has a first predetermined body emittance factor for the body determined for the body by the ratio method. An emittance correcting pyrometer having a lower temperature to emittance factor ratio sensitivity than the bodytemperature-measuring pyrometer is disposed adjacent the bodytemperature-measuring pyrometer in the sight tube means. The emittance-correcting pyrometer has a second predetermined emittance factor for the body determined for the body by the ratio method. Mirror means are in said sight tube means for directing a portion or one wavelength band of the combined thermal radiation to the body-temperature-measuring pyrometer and another portion or other wavelength band of the combined thermal radiation to the emittance-correcting measuring pyrometer. The body-temperature-measuring pyrometer is operable to measure the temperature of the body with a first range of stepped emittance factors in the range from the first predetermined body emittance factor to 1.00 to determine a first measured temperature range for the body with a first temperature error range. The emittancecorrecting pyrometer is operable to measure the temperature of the body with a second range of stepped emittance factors in the range from the second predetermined emittance factor to 1.00 to determine a range of emittance-correcting factors corresponding to the first measured temperature range. This range of emittancecorrecting factors indicates one half-portion of the halfportions defined by the first predetermined emittance factor and the midpoint between the first predetermined emittance factor and 1.00 and the midpoint and 1.00 of the first range of stepped emittance factors in which an adjusted emittance factor for the body-measuring pyrometer lies. The body temperature pyrometer is then set at the midpoint of the one half-portion as such adjusted emittance factor to measure the temperature of the body within the minimum range of temperature error. The method includes the steps of directing a portion or one wavelength band of the combined thermal radiation to a body temperature-measuring pyrometer having a high temperature to emittance factor ratio sensitivity and a first predetermined body emittance factor the the body as determined for the body by the ratio method and another portion or other wavelength band of the combined thermal radiation to an emittance-correcting measuring pyrometer having a lower temperature to emittance factor ratio sensitivity than the body-temperature-measurIng pyrometer and a second predetermined body emittance factor for the body as determined for the body by the ratio method; measuring the temperature of the body with a first range of stepped emittance factors in the range from the first predetermined body emittance factor to 1.00 to determine a first measured temperature range for the body with a first temperature error range; and measuring the temperature of the body with a second range of stepped emittance factors in the range from the second predetermined emittance factor to 1.00 to determine a range of second emittance factors corresponding to the first measured temperature range. The range of second emittance factors for the emittancecorrecting pyrometer in the first measured temperature range indicates one half-portion of the half-portions defined by the first predetermined emittance factor and the midpoint between the first predetermined emittance factor and 1.00 and the midpoint and 1.00 of the first range of stepped emittance factors in which an adjusted emittance factor lies. Also included are the steps of setting the body temperature pyrometer at the midpoint of the one half-portion as such adjusted emittance factor, and measuring the temperature of the body with the minimum range of temperature error.
Inventors
- 👤 Thomas P Murray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:14
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/60
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
425 words
In combination: a. furnace means having walls which define a heating cavity, b. a body disposed in said heating cavity, c. heating means associated with said furnace means for heating said body to a predetermined temperature, and d. apparatus communicating with said heating cavity for determining the proper emittance factor for said apparatus for the combined thermal radiation from said body and the reflected thermal radiation from said walls so that said apparatus will measure the temperature of said body with a minimum range of temperature error, said apparatus having: 1. sight tube means disposed in one of said walls and in registry with said body, 2. a body-temperature-measuring pyrometer having a bodytemperature-measuring sensor and a recording means, said bodytemperature-measuring sensor 2 having a high temperature to emittance factor ratio sensitivity and being disposed in said sight tube means, a. said indicating body-temperature-measuring pyrometer having a first predetermined body emittance factor for said body determined for said body by the ratio method, 3. an emittance-correcting pyrometer having an emittancecorrecting sensor connected to said recording means, said emittance-correcting sensor having a temperature to emittance factor ratio sensitivity than said body-temperature-measuring sensor and being disposed adjacent said body-temperaturemeasuring pyrometer in said sight tube means. a. said emittance-correcting pyrometer having a second predetermined emittance factor for said body determined for said body by the ratio method, 4. mirror means in said sight means for directing a portion of said combined thermal radiation to said body temperature measuring pyrometer and another portion of said combined thermal radiation to said emittance-correcting pyrometer, 5. said body temperature pyrometer being operable to measure the temperature of said body with a first range of stepped emittance factors in the range from said first predetermined body emittance factor to 1.00 to determine a first indicated temperature range for said body with a first temperature error range, 6. said emittance-correcting pyrometer being operable to measure the temperature of said body with a second range of stepped emittance factors in the range from said second predetermined emittance factor to 1.00 to determine an indicating range of reflected emittance factors corresponding to said first indicated temperature range, a. said range of reflected emittance factors indicating in which one half-portion of the range of emittance factors defined by said first predetermined emittance factor an adjusted emittance factor lies, 7. said body temperature pyrometer being set at the midpoint of said one half-portion of said first range of emittance factors as such adjusted emittance factors to measure the temperature of said body with said minimum range of temperature error.
Claim 2
Dependent Claim
425 words
In combination: a. furnace means having walls which define a heating cavity, b. a body disposed in said heating cavity, c. heating means associated with said furnace means for heating said body to a predetermined temperature, and d. apparatus communicating with said heating cavity for determining the proper emittance factor for said apparatus for the combined thermal radiation from said body and the reflected thermal radiation from said walls so that said apparatus will measure the temperature of said body with a minimum range of temperature error, said apparatus having: 1. sight tube means disposed in one of said walls and in registry with said body, 2. a body-temperature-measuring pyrometer having a bodytemperature-measuring sensor and a recording means, said bodytemperature-measuring sensor 2 having a high temperature to emittance factor ratio sensitivity and being disposed in said sight tube means, a. said indicating body-temperature-measuring pyrometer having a first predetermined body emittance factor for said body determined for said body by the ratio method, 3. an emittance-correcting pyrometer having an emittancecorrecting sensor connected to said recording means, said emittance-correcting sensor having a temperature to emittance factor ratio sensitivity than said body-temperature-measuring sensor and being disposed adjacent said body-temperaturemeasuring pyrometer in said sight tube means. a. said emittance-correcting pyrometer having a second predetermined emittance factor for said body determined for said body by the ratio method, 4. mirror means in said sight means for directing a portion of said combined thermal radiation to said body temperature measuring pyrometer and another portion of said combined thermal radiation to said emittance-correcting pyrometer, 5. said body temperature pyrometer being operable to measure the temperature of said body with a first range of stepped emittance factors in the range from said first predetermined body emittance factor to 1.00 to determine a first indicated temperature range for said body with a first temperature error range, 6. said emittance-correcting pyrometer being operable to measure the temperature of said body with a second range of stepped emittance factors in the range from said second predetermined emittance factor to 1.00 to determine an indicating range of reflected emittance factors corresponding to said first indicated temperature range, a. said range of reflected emittance factors indicating in which one half-portion of the range of emittance factors defined by said first predetermined emittance factor an adjusted emittance factor lies, 7. said body temperature pyrometer being set at the midpoint of said one half-portion of said first range of emittance factors as such adjusted emittance factors to measure the temperature of said body with said minimum range of temperature error.
Claim 3
Dependent Claim
55 words
a body-temperature-measuring pyrometer having a body-temperature-measuring sensor and a recording means, said body-temperature-measuring sensor 2 having a high temperature to emittance factor ratio sensitivity and being disposed in said sight tube means, a. said indicating body-temperature-measuring pyrometer having a first predetermined body emittance factor for said body determined for said body by the ratio method,
Claim 4
Dependent Claim
55 words
a body-temperature-measuring pyrometer having a body-temperature-measuring sensor and a recording means, said body-temperature-measuring sensor 2 having a high temperature to emittance factor ratio sensitivity and being disposed in said sight tube means, a. said indicating body-temperature-measuring pyrometer having a first predetermined body emittance factor for said body determined for said body by the ratio method,
Claim 5
Dependent Claim
121 words
Apparatus for determining the proper emittance factor for said apparatus for the combined thermal radiation from a body, disposed in a heating cavity defined by the walls of a furnace means and heated to a predetermined temperature by heating means associated with said furnace means, and the reflected thermal radiation from said walls so that said apparatus will measure the temperature of said body with a minimum range of temperature error, said apparatus having: a. sight tube means disposed in one of said walls and in registry with said body, b. a body-temperature-measuring pyrometer having a body-temperature-measuring sensor and a recording means, said body-temperature-measuring sensor a high temperature to emittance factor ratio sensitivity and being disposed in said sight tube means,
Claim 6
Dependent Claim
121 words
Apparatus for determining the proper emittance factor for said apparatus for the combined thermal radiation from a body, disposed in a heating cavity defined by the walls of a furnace means and heated to a predetermined temperature by heating means associated with said furnace means, and the reflected thermal radiation from said walls so that said apparatus will measure the temperature of said body with a minimum range of temperature error, said apparatus having: a. sight tube means disposed in one of said walls and in registry with said body, b. a body-temperature-measuring pyrometer having a body-temperature-measuring sensor and a recording means, said body-temperature-measuring sensor a high temperature to emittance factor ratio sensitivity and being disposed in said sight tube means,
Claim 7
Independent Claim
255 words
The method of determining a low error emittance factor for a radiation pyrometer for the combined thermal radiation from a body, disposed in a heating cavity defined by the walls of a furnace means and heated to a predetermined temperature by heating means associated with said furnace means, and the reflected thermal radiation from said walls to measure the temperature of said body with a minimum range of temperature error, said method including the steps of: a. directing a portion of said combined thermal radiation to a body-temperature-measuring pyrometer having a high temperature to emittance factor ratio sensitivity and a first predetermined body emittance factor for said body as determined for said body by the ratio method and another portion of said combined thermal radiation to an emittance-correcting pyrometer having a lower temperature to emittance factor ratio sensitivity than said body-temperature-measuring pyrometer, and a second predetermined body emittance factor for said body as determined for said body by the ratio method, b. measuring the temperature of said body by said body-temperature-measuring pyrometer with a first range of stepped emittance factors in the range from said first predetermined body emittance factor to 1.00 to determine a first indicated temperature range for said body with a first temperature error range, c. measuring the temperature of said body by said emittance-correcting pyrometer with a second range of stepped emittance factors in the range from said second predetermined emittance factor to 1.00 in order to determine a range of reflected emittance factors corresponding to said first indicated temperature range,
Claim 8
Independent Claim
255 words
The method of determining a low error emittance factor for a radiation pyrometer for the combined thermal radiation from a body, disposed in a heating cavity defined by the walls of a furnace means and heated to a predetermined temperature by heating means associated with said furnace means, and the reflected thermal radiation from said walls to measure the temperature of said body with a minimum range of temperature error, said method including the steps of: a. directing a portion of said combined thermal radiation to a body-temperature-measuring pyrometer having a high temperature to emittance factor ratio sensitivity and a first predetermined body emittance factor for said body as determined for said body by the ratio method and another portion of said combined thermal radiation to an emittance-correcting pyrometer having a lower temperature to emittance factor ratio sensitivity than said body-temperature-measuring pyrometer, and a second predetermined body emittance factor for said body as determined for said body by the ratio method, b. measuring the temperature of said body by said body-temperature-measuring pyrometer with a first range of stepped emittance factors in the range from said first predetermined body emittance factor to 1.00 to determine a first indicated temperature range for said body with a first temperature error range, c. measuring the temperature of said body by said emittance-correcting pyrometer with a second range of stepped emittance factors in the range from said second predetermined emittance factor to 1.00 in order to determine a range of reflected emittance factors corresponding to said first indicated temperature range,
Claim 9
Dependent Claim
60 words
an emittance-correcting pyrometer having an emittance-correcting sensor connected to said recording means, said emittance-correcting sensor having a temperature to emittance factor ratio sensitivity than said body-temperature-measuring sensor and being disposed adjacent said body-temperature-measuring pyrometer in said sight tube means. a. said emittance-correcting pyrometer having a second predetermined emittance factor for said body determined for said body by the ratio method,
Claim 10
Dependent Claim
60 words
an emittance-correcting pyrometer having an emittance-correcting sensor connected to said recording means, said emittance-correcting sensor having a temperature to emittance factor ratio sensitivity than said body-temperature-measuring sensor and being disposed adjacent said body-temperature-measuring pyrometer in said sight tube means. a. said emittance-correcting pyrometer having a second predetermined emittance factor for said body determined for said body by the ratio method,
Claim 11
Dependent Claim
33 words
mirror means in said sight means for directing a portion of said combined thermal radiation to said body temperature measuring pyrometer and another portion of said combined thermal radiation to said emittance-correcting pyrometer,
Claim 12
Dependent Claim
33 words
mirror means in said sight means for directing a portion of said combined thermal radiation to said body temperature measuring pyrometer and another portion of said combined thermal radiation to said emittance-correcting pyrometer,
Claim 13
Dependent Claim
28 words
The apparatus recited in claim 2 and having chopping means ahead of said mirror means and operating at a fixed frequency for periodically interrupting the combined thermal radiation.
Claim 14
Dependent Claim
17 words
The apparatus recited in claim 4 wherein said body temperature measuring sensor generates first alternating electrical signals.
Claim 15
Dependent Claim
49 words
said body temperature pyrometer being operable to measure the temperature of said body with a first range of stepped emittance factors in the range from said first predetermined body emittance factor to 1.00 to determine a first indicated temperature range for said body with a first temperature error range,
Claim 16
Dependent Claim
49 words
said body temperature pyrometer being operable to measure the temperature of said body with a first range of stepped emittance factors in the range from said first predetermined body emittance factor to 1.00 to determine a first indicated temperature range for said body with a first temperature error range,
Claim 17
Dependent Claim
77 words
said emittance-correcting pyrometer being operable to measure the temperature of said body with a second range of stepped emittance factors in the range from said second predetermined emittance factor to 1.00 to determine an indicating range of reflected emittance factors corresponding to said first indicated temperature range, a. said range of reflected emittance factors indicating in which one half-portion of the range of emittance factors defined by said first predetermined emittance factor an adjusted emittance factor lies,
Claim 18
Dependent Claim
77 words
said emittance-correcting pyrometer being operable to measure the temperature of said body with a second range of stepped emittance factors in the range from said second predetermined emittance factor to 1.00 to determine an indicating range of reflected emittance factors corresponding to said first indicated temperature range, a. said range of reflected emittance factors indicating in which one half-portion of the range of emittance factors defined by said first predetermined emittance factor an adjusted emittance factor lies,
Claim 19
Dependent Claim
24 words
The apparatus recited in claim 5 and having a first preamplifier means connected to said body-temperature-measuring detector for amplifying said first alternating electrical signals.
Claim 20
Dependent Claim
18 words
The apparatus recited in claim 5 and having first filter means for filtering said first alternating electrical signals.
Claim 21
Dependent Claim
39 words
said body temperature pyrometer being set at the midpoint of said one half-portion of said first range of emittance factors as such adjusted emittance factors to measure the temperature of said body with said minimum range of temperature error.
Claim 22
Dependent Claim
39 words
said body temperature pyrometer being set at the midpoint of said one half-portion of said first range of emittance factors as such adjusted emittance factors to measure the temperature of said body with said minimum range of temperature error.
Claim 23
Dependent Claim
17 words
The apparatus recited in claim 4 wherein said reflected emittance correcting sensor generates second alternating electrical signals.
Claim 24
Dependent Claim
25 words
The apparatus recited in claim 8 and having a second preamplifier means connected to said reflected emittance-correcting detector for amplifying said second alternating electrical signals.
Claim 25
Dependent Claim
18 words
The apparatus recited in claim 8 and having second filter means for filtering said second alternating electrical signals.
Claim 26
Dependent Claim
16 words
The method recited in claim 3 and including the step of chopping said combined thermal radiation.
Claim 27
Dependent Claim
22 words
The method recited in claim 11 and including the step of producing first alternating electrical signals from said body temperature measuring detector.
Claim 28
Dependent Claim
17 words
The method recited in claim 12 and including the step of amplifying said first alternating electrical signals.
Claim 29
Dependent Claim
17 words
The method recited in claim 12 and including the step of recording said first alternating electrical signals.
Claim 30
Dependent Claim
17 words
The method recited in claim 12 and including the step of filtering said first alternating electrical signals.
Claim 31
Dependent Claim
21 words
The method recited in claim 11 and including the step of producing second alternating electrical signals from said reflected emittance-correcting pyrometer.
Claim 32
Dependent Claim
17 words
The method recited in claim 16 and including the step of amplifying said second alternating electrical signals.
Claim 33
Dependent Claim
17 words
The method recited in claim 16 and including the step of recording said second alternating electrical signals.
Claim 34
Dependent Claim
17 words
The method recited in claim 16 and including the step of filtering said second alternating electrical signals.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-04 | 1975-04-05 | 1975-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-04 | 1979-04-05 | 1979-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-04 | 1983-04-05 | 1983-10-05 | $7700.00 | Window Closed / Lapsed |