US1937722A - Dust and smoke density measuring device - Google Patents
Dust and smoke density measuring device Download PDFInfo
- Publication number
- US1937722A US1937722A US55719231A US1937722A US 1937722 A US1937722 A US 1937722A US 55719231 A US55719231 A US 55719231A US 1937722 A US1937722 A US 1937722A
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- United States
- Prior art keywords
- windows
- window
- chamber
- radiation
- dust
- Prior art date
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- Expired - Lifetime
Links
- 239000000428 dust Substances 0.000 title description 18
- 239000000779 smoke Substances 0.000 title description 18
- 230000005855 radiation Effects 0.000 description 46
- 239000007789 gas Substances 0.000 description 29
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 238000010438 heat treatment Methods 0.000 description 6
- 230000004048 modification Effects 0.000 description 6
- 238000012986 modification Methods 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 239000007859 condensation product Substances 0.000 description 4
- 230000008021 deposition Effects 0.000 description 4
- 239000011521 glass Substances 0.000 description 4
- 230000005494 condensation Effects 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 2
- 230000002939 deleterious effect Effects 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005485 electric heating Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 239000005297 pyrex Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N21/15—Preventing contamination of the components of the optical system or obstruction of the light path
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N21/15—Preventing contamination of the components of the optical system or obstruction of the light path
- G01N2021/152—Scraping; Brushing; Moving band
Description
1933- A. w. smdu ET AL- 1,937,122
DUST AND SMOKE DENSITY MEASURING DEVICE Filed Aug. 14. 1931 2 Sheets-Sheet 1 Dec. 5, 1933. A. w. SIMON ET AL DUST AND SMOKE DENSITY MEASURING DEVICE 2 Sheets-Sheet 2 Filed Aug mvzsm'mw ALFWEE WALTER 5mm ELEM Patented D 5, 3 1,937,722
UNITED STATES PATENT OFFICE DUST AND SMOKE DENSITY MEASURING DEVICE Alfred Walter Simon, Birmingham, Leonard Car-others Kron, Ensley, and Henry Raymond, Pratt City, Ala.
I Application August 14, 1931. Serial No. 557,192
Claims. (CI. 88-14) This invention relates to dust or smoke conof the present invention reference should be centration meter devices such as is disclosed in made to the accompanying drawings wherein:
copending application Serial No. 890,634, filed Fig.1 is a sectional side elevation view of one September 5, .1929. 1 end of the dust concentration'meter. device illus- 6 In the above identified copending application trating one modification of the improved window 60 a dust or smoke. concentration meter device is cleaning feature of the present invention; disclosed in which a beam of radiation is passed Fig. 2 shows a cross-sectional view of the same through a. predetermined known and constant illustrating a second modification;
distance, the smoke or. dust containing gas or a Fig. 3 illustrates a third modification;
representative sample thereof is passed through Fig. 4 is a cross-sectional view of the same; 65
the beam and the emergent radiation utilized by and means of a light sensitive device to energize Fig. 5 is a longitudinal section disclosing the recording or indicating mechanism, graduated to entire meter device of the present invention with indicate the density of the gas. the electrical circuits shown schematically.
In the apparatus disclosed the beam of light Referring to Fig. 1, the details of the invention 70 is projected through a light permeable window for carrying out the heating of the window with for a predetermined distance, thence through a a hot air stream are shown. In this figure, 1 glass window to the radiation sensitive device. represents one end of the dust meter device of The smoke or dust laden gases are circulated bethe above identified application, in particular,
tween the two windows. To prevent the dust the end carrying the Mazda lamp or light source; and smoke from collecting upon and interfering 2 is the radiation permeable window, the surwith the transmission of the radiation through face of which opposite to the light source 5 is to the windows mechanical wiping means are probe kept free of moisture. A second window 3 is vided to keep the windows clean. interposed between the first window 2 and the It is found however that when the smoke or lamp 5 and lens 6 (the lens 6 itself might per- 80 dust'containing gases are wet" or moist with form this function if of heat resisting glass). water, or volatile substances such as oil, tar, Thru the cylindrical chamber4 between the two parafines and the like, the windows tend to bewindows 2, 3, heated air is circulated. "Ihis come clouded or smeared. with the condensates heated air comes from an air line 7, passes thru of such substances and that the mechanical wipa heater 8, and then enters the space 4 thru the, 85 ing means are not entirely effective in keeping pipe 9 and leaves thru the pipe 10.. In place of the windows clean. heated air, dry steam or other light permeable It is one of the objects of this invention to imgas can be used. The air if not perfectly clean prove the mechanical cleaning of the light can be filtered in any convenient manner before transparent windows of the above identified admission to the chamber 4.
application. A second modification of the present invention It is another object of this invention to prois illustrated in Fig. 2 wherein two small water vide means to eliminate deleterious condensate jets are played upon the window surface, the jets materials from the light transparent windows of so shaped as to spread the water well over the 40 the above identified application. windows and symmetrically placed with respect 95 It is another object of this invention to imto the wiper blade and the light beam so as not prove the operating characteristics of the dust to interfere with either. The water absorbs concentration meter of the above identified apsome of the light and heat energy from the lamp plication. 5, but this, as long as it is a constant fraction, is
Other objects and advantages will become apimmaterial, since it is corrected for in setting parent as the invention is more fully disclosed. the meter device to a clear reading. In order to In accordance with the objects of the present keep this fractional part constant, the water flow invention we propose to supplement the wipers must be kept substantially constant. by a stream of water or other liquid solvent to In Fig. 2, 20 indicates the casing of the meter the condensing materials which is directed upon device in section; 21, the surface of the window 105 the windows; or to keep the windows hot by any facing the gas stream; 22, the blade of the wiper convenient means so that moisture or other confor the window; 23, the spring and holder for. densate materials will not be apt to condense the wiper blade 24, the shaft actuating the upon or to remain therein if it does condense. wiper; and 25, the water sprays for the windows.
Before further disclosing the nature and scope Means such as outlet 26 can be provided to carry off the water from the interior of the recorder pipe 20.
The second alternative (Fig. 3) is particularly practical, where the moisture is not excessive and comprises means to keep the surface of the window hot to prevent the condensation of moisture thereon, and to evaporate any condensate droplets which might accidentally be deposited on the windows.
Referring to Fig. 3, one means of keeping the window warm comprises suitable electric heating elements placed adjacent the windows. The glass must be a heat resisting glass such as pyrex, or quartz. A second means may comprise, for example, a stream of heated air impinging on the window to keep it hot. These two means may be combined to form the complete modification shown in Fig. 3. Since hot air might effect the thermopile, or the light, if it came in contact with it, the double window should be used, the second window being interposed between the lamp or thermopile and the hot air chamber. This makes it possible to keep the first window hot and still have the light or thermopile chamber cold. If desired, these light or thermopile elements can be placed some distance from the window so that the hot air will not afiect them. The hot air can be supplied by heating electrically and forcing it thru by means of a small fan, or better, air from a compressed air line can be used after being passed thru a suitable heating arrangement, such as is indicated in Fig. 1 at 8.
In place of heated air impinging on the windows the latter can also be heated by means of the heating coil placed along its periphery, the center of the window being heated by heat conducted from the periphery of the window to the center by the air stream. This is specifically shown in Fig. 3, where 31 represents the window and 35 the heating coil. The latter is embedded in a refractory and pressed close to the surface of the window adjacent the casing 30. The heated or unheated air is conducted in by one of the pipes 32 and leaves by the other. Fig. 4 is a cross-sectional view of the same.
Referring to Fig. 5 the meter device of the present invention is shown mounted to record the density of gases flowing in a conduit, pipe, smokestack or the like 40. The gas chamber 41 of the meter is substantially a by-pass conduit for pipe 40, the gases flowing in pipe 40 being conducted thereto by means of conduit 42 and therefrom by conduit 43 substantially as indicated by arrows.
As shown, at each end of chamber 41 are the radiation permeable windows 22' spaced a determined distance apart. These windows it is desired to maintain substantially free from deleterious and radiation obscuring deposits and condensate materials from the gases flowing through the chamber. Mechanical wiping means 22-22' have been utilized but it has been found that with certain types of gases these are not entirely effective due to the fact that most gases contain radiation absorbing volatile fluids such as water, tar and the like which tend to condense thereon. Accordingly means must be provided as illustrated in Figs. 1 to 4 inclusive to prevent the condensation of these materials upon the window faces.
In Fig. 5 the specific means disclosed is the means substantially set forth in Fig. l and the same numerals applied in Fig. 1 are applied in Fig. 5. The meansdisclosed in Figs. 2 to 4 inclusive however may be substituted therefor without departing essentially from the nature and scope of the present invention.
In operation the radiation evolved from light source 5 energized by electric current from source 44 passes through lens 6 and thence through light permeable windows 3 and 2 spaced apart to form a heating chamber suitable for the purposes of the present invention. The radiation then passes through chamber 41 through light permeable windows 2'--3' spaced similarly as are windows 32, then through lens 6' where it is concentrated upon radiation sensitive device 45. The current flow in device 45 in response to variations in the radiation falling thereon energizes measuring and/or recording instrument 46. In the heat chambers between the light permeable windows 3-2 and 2'-3, heated air is passed substantially as is shown and heretofore described with respect to Fig. 1. Mechanical wiping means 22-22 operates to continuously maintain the face of windows 2-2 adjacent the gas stream substantially free from radiation absorbing deposits from the flowing gas stream while the heated air prevents the condensation of light obscuring condensates thereon from the gas stream. In this manner, the true density of the gas flowing between windows 2-2 can be at all time accurately determined.
'It is apparent from the above specification and drawings that there may be many modifications and departures made of the present invention without departing essentially from the nature and scope thereof as may be set forth in the accompanying claims.
What is claimed:
1. A dust concentration meter device comprising a chamber, means to pass smoke laden gases into and out of said chamber, two radiation transparent windows disposed in opposite walls of said chamber between which the smoke laden gases are conducted, wiper means to maintain the inside faces of said windows substantially free from radiation absorbing deposits, means to mechanically operate said wiper means, means to project a fluid upon the said inside faces of said windows, means to drain said fluid from said chamber, means disposed adjacent one of said windows and exteriorly said chamber to project radiation through said window into said chamber and through the opposite window, radiation sensitive means disposed adjacent the said opposite window and exteriorly said chamber to receive the projected radiation, and means to measure the amount of said received radiation.
2. A dust concentration meter device comprising a chamber, means to pass smoke laden gases into and out of said chamber, two radiation transparent windows disposed in opposite walls of said chamber between which the smoke laden gases are conducted, wiper means to maintain the inside faces of said windows substantially free from radiation absorbing deposits, means to mechanically operate said wiper means, means to heat said windows to a temperature sufiicient to prevent the deposition on said inside window faces of radiation absorbing condensation products from said gases, means disposed adjacent one of said Windows and exteriorly said chamber to project radiation through said window into said chamber and through the opposite window, radiation sensitive means disposed adjacent the said opposite window and exteriorly said chamber to receive the projected radiation and means to measure the amount of said received radiaion.
3. A dust concentration meter device comprising a chamber, means to pass smoke laden gases into and out of said chamber, two radiation transparent windows disposed in opposite walls of said chamber between which the smoke laden gases are conducted, wiper means to maintain the inside faces of said windows substantially free from radiation absorbing deposits, means to mechanically operate said wiper means, means to direct a stream of heated air against the outside faces of said windows to heat said windows to a temperature sutficient to prevent the deposition on said inside window faces of radiation absorbing condensation products from said gases, means disposed adjacent one of said windows and exteriorly said chamber to project radiation through said window into said chamber and through the opposite window, radiation sensitive means disposed adjacent the said opposite window and exteriorly said chamber to receive the projected radiation and means to measure the amount of said received radiation.
4. A dust concentration meter device comprising a chamber, means to pass smoke laden gases into and out of said chamber, two radiation transparent windows disposed in opposite walls of said chamber between which the smoke laden gases are conducted, wiper means to maintain the inside faces of said windows substantially free from radiation absorbing deposits, means to mechanically operate said wiper means, means to position an electrical heater element adjacent the outer faces of said windows to heat said windows to a temperature suflicient to prevent the deposition on said inside window faces of radiation absorbing condensation products from said gases, means disposed adjacent one of said windows and exteriorly said chamber to project radiation through said window into said chamber and through the opposite window, radiation sensitive means disposed adjacent the said opposite window and exteriorly said chamber to receive the/projected radiation and means to measure the amount of said re ceived radiation.
5. A dust concentration meter device comprising a chamber, means to pass smoke laden gases into and out of said chamber, two radiation transparent windows disposed in opposite walls of said chamber between which the smoke laden gases are conducted, wiper means to maintain the inside faces of said windows substantially free from radiation absorbing deposits, means to mechanically operate said wiper means, means to direct a flow of air across the outside faces of said windows and means to heat said air to a temperature suflicient to prevent the deposition on said inside window faces of radiation absorbing condensation products fromsaid gases, means disposed adjacent one of said windows and exteriorly said chamber-t0 project radiation through said window into said chamber and through the opposite window, radiation sensitive means disposed adjacent the said opposite window and exteriorly said-chamber to receive the projected radiation and means to measure the amount of said received radiation.
ALFRED WALTER SIMON. LEONARD CAROTHERS KRON. HENRY RAYMOND.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US55719231 US1937722A (en) | 1931-08-14 | 1931-08-14 | Dust and smoke density measuring device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US55719231 US1937722A (en) | 1931-08-14 | 1931-08-14 | Dust and smoke density measuring device |
Publications (1)
Publication Number | Publication Date |
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US1937722A true US1937722A (en) | 1933-12-05 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US55719231 Expired - Lifetime US1937722A (en) | 1931-08-14 | 1931-08-14 | Dust and smoke density measuring device |
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Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2419914A (en) * | 1944-11-30 | 1947-04-29 | Airdesign & Fabrication Inc | Method and apparatus for detecting suspended matter in fluids |
US2470511A (en) * | 1944-07-12 | 1949-05-17 | James B Shaver | Detection of impurities |
US2483876A (en) * | 1947-01-21 | 1949-10-04 | William J Boyer | Photometric apparatus |
US2513283A (en) * | 1946-09-28 | 1950-07-04 | C O Two Fire Equipment Co | Photoelectric convection smoke detector |
US2856542A (en) * | 1954-12-02 | 1958-10-14 | Mcpheeters August Earnest | Apparatus for preventing the entry of foreign matter in photoelectric cell unit |
US2878716A (en) * | 1955-06-24 | 1959-03-24 | Elliott Brothers London Ltd | Rotary window for gas inspection |
US2927218A (en) * | 1958-09-26 | 1960-03-01 | Linderman Engineering Company | Pinhole detector |
US2932747A (en) * | 1957-07-23 | 1960-04-12 | United States Steel Corp | Self-cleaning light receiver for pin hole detector |
US3020795A (en) * | 1959-05-14 | 1962-02-13 | Du Pont | Fluid inspection apparatus |
US3094625A (en) * | 1959-11-06 | 1963-06-18 | Cornell Aeromautical Lab Inc | Photoelectric apparatus for measuring the size of particles |
US3251999A (en) * | 1962-11-26 | 1966-05-17 | Oscar Mayer & Company Inc | Photoelectric system for measuring the density of smoke |
DE1244327B (en) * | 1960-10-13 | 1967-07-13 | Marconi Co Ltd | Method and device for cooling an observation window for furnaces and for preventing deposits on the side of the window facing the furnace interior |
US3628028A (en) * | 1968-03-01 | 1971-12-14 | Honeywell Inc | Window cleaning apparatus for photometric instruments |
US3666951A (en) * | 1969-04-16 | 1972-05-30 | Hell Rudolf Dr Ing | Device for detecting defects in continuous web material |
US3714445A (en) * | 1969-11-06 | 1973-01-30 | Inst Nat Rech Agrenomique | Apparatus for optical measurements of microbial cultures |
US3851333A (en) * | 1969-07-31 | 1974-11-26 | S Fishman | Spray injection for testing an ultrasonic liquid level detector |
US4292530A (en) * | 1980-03-03 | 1981-09-29 | Minnesota Mining And Manufacturing Company | Developer material level sensor |
EP0337108A2 (en) * | 1988-04-11 | 1989-10-18 | Westinghouse Electric Corporation | Method and apparatus for periodically obtaining accurate opacity monitor readings of an exhaust gas stream |
AT396999B (en) * | 1985-05-08 | 1994-01-25 | Strahlen Umweltforsch Gmbh | SYSTEM FOR TURBIDIMETRIC MEASUREMENT AND CONTROL OF MICROORGANISMS |
US6390016B1 (en) * | 1999-08-09 | 2002-05-21 | Penberthy, Inc. | Sight flow indicator |
US20140268157A1 (en) * | 2013-03-13 | 2014-09-18 | Campbell Scientific, Inc. | Open-path gas analyzer with environmental protection |
US20220155216A1 (en) * | 2020-11-18 | 2022-05-19 | Kidde Technologies, Inc. | Clean gas curtain to prevent particle buildup during concentration measurement |
-
1931
- 1931-08-14 US US55719231 patent/US1937722A/en not_active Expired - Lifetime
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2470511A (en) * | 1944-07-12 | 1949-05-17 | James B Shaver | Detection of impurities |
US2419914A (en) * | 1944-11-30 | 1947-04-29 | Airdesign & Fabrication Inc | Method and apparatus for detecting suspended matter in fluids |
US2513283A (en) * | 1946-09-28 | 1950-07-04 | C O Two Fire Equipment Co | Photoelectric convection smoke detector |
US2483876A (en) * | 1947-01-21 | 1949-10-04 | William J Boyer | Photometric apparatus |
US2856542A (en) * | 1954-12-02 | 1958-10-14 | Mcpheeters August Earnest | Apparatus for preventing the entry of foreign matter in photoelectric cell unit |
US2878716A (en) * | 1955-06-24 | 1959-03-24 | Elliott Brothers London Ltd | Rotary window for gas inspection |
US2932747A (en) * | 1957-07-23 | 1960-04-12 | United States Steel Corp | Self-cleaning light receiver for pin hole detector |
US2927218A (en) * | 1958-09-26 | 1960-03-01 | Linderman Engineering Company | Pinhole detector |
US3020795A (en) * | 1959-05-14 | 1962-02-13 | Du Pont | Fluid inspection apparatus |
US3094625A (en) * | 1959-11-06 | 1963-06-18 | Cornell Aeromautical Lab Inc | Photoelectric apparatus for measuring the size of particles |
DE1244327B (en) * | 1960-10-13 | 1967-07-13 | Marconi Co Ltd | Method and device for cooling an observation window for furnaces and for preventing deposits on the side of the window facing the furnace interior |
US3251999A (en) * | 1962-11-26 | 1966-05-17 | Oscar Mayer & Company Inc | Photoelectric system for measuring the density of smoke |
US3628028A (en) * | 1968-03-01 | 1971-12-14 | Honeywell Inc | Window cleaning apparatus for photometric instruments |
US3666951A (en) * | 1969-04-16 | 1972-05-30 | Hell Rudolf Dr Ing | Device for detecting defects in continuous web material |
US3851333A (en) * | 1969-07-31 | 1974-11-26 | S Fishman | Spray injection for testing an ultrasonic liquid level detector |
US3714445A (en) * | 1969-11-06 | 1973-01-30 | Inst Nat Rech Agrenomique | Apparatus for optical measurements of microbial cultures |
US4292530A (en) * | 1980-03-03 | 1981-09-29 | Minnesota Mining And Manufacturing Company | Developer material level sensor |
AT396999B (en) * | 1985-05-08 | 1994-01-25 | Strahlen Umweltforsch Gmbh | SYSTEM FOR TURBIDIMETRIC MEASUREMENT AND CONTROL OF MICROORGANISMS |
EP0337108A2 (en) * | 1988-04-11 | 1989-10-18 | Westinghouse Electric Corporation | Method and apparatus for periodically obtaining accurate opacity monitor readings of an exhaust gas stream |
EP0337108A3 (en) * | 1988-04-11 | 1990-12-27 | Westinghouse Electric Corporation | Method and apparatus for periodically obtaining accurate opacity monitor readings of an exhaust gas stream |
US6390016B1 (en) * | 1999-08-09 | 2002-05-21 | Penberthy, Inc. | Sight flow indicator |
US20140268157A1 (en) * | 2013-03-13 | 2014-09-18 | Campbell Scientific, Inc. | Open-path gas analyzer with environmental protection |
US20220155216A1 (en) * | 2020-11-18 | 2022-05-19 | Kidde Technologies, Inc. | Clean gas curtain to prevent particle buildup during concentration measurement |
US11781969B2 (en) * | 2020-11-18 | 2023-10-10 | Kidde Technologies, Inc. | Clean gas curtain to prevent particle buildup during concentration measurement |
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