US3890221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Translucency/opaque sorting
Assignee: Sortex Company of North America Inc
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Filing: 1973-12-14
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Granted: 1975-06-17
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Expires: 1993-12-14
Abstract
Abstract A method and apparatus for sorting particles according to the degree of transparency thereof wherein the particles are passed seriatim through a viewing zone or chamber and are illuminated therein from one side to produce a shadow pattern on a plurality of photosensors opposite the illuminating source. The photosensors scan across the shadow pattern a plurality of times as the particles pass through the viewing zone. The photosensors in ''''gray'''' areas of the shadow pattern produce one signal and photosensors in ''''black'''' areas of the shadow produce a second signal. Each type of signal is counted and the counts are integrated as multiple scans are made across the moving shadow pattern to give an indication of the relative gray and black areas in the shadow pattern. Particles whose black areas exceed gray areas by a predetermined amount are sorted from the remainder of the particles whose black areas are less than the gray areas by a predetermined amount.
Inventors
- 👤 Urs Muehlethaler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:51
CPC Classifications
B; B07; B07C; B07C5/00; B07C5/34; B07C5/342; B07C5/3422; Y; Y10; Y10S; Y10S209/00; Y10S209/908
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
143 words
A METHOD OF SORTING PARTICLES ACCORDING TO THEIR DEGREE OF TRANSPARENCY COMPRISING THE STEPS OF: PASSING EACH PARTICLE SERIATIM THROUGH A VIEWING ZONE; ILLUMINATING ONE SIDE OF THE PARTICLES TO PRODUCE A SHADOW PATTERN ON A SURFACE IN SAID VIEWING ZONE, THE SHADOW PATTERN OF AT LEAST SOME PARTICLES HAVING A FIRST AREA OF A FIRST LEVEL OF LIGHT ATTENUATION AND A SECOND AREA OF A SECOND LEVEL OF LIGHT ATTENUATION DIFFERENT FROM SAID FIRST LEVEL, EACH OF SAID FIRST AND SECOND AREAS BEING LESS THAN THE TOTAL AREA OF THE SHODOW PATTERN OF SAID PARTICLES, MEASURING THE RELATIVE SIZES OF THE FIRST AND SECOND AREAS OF LIGHT ATTENUATION; AND SORTING THOSE PARTICLES WHICH PRODUCE A SHADOW PATTERN WHOSE RATIO OF FIRST AREA TO SECOND AREA EXCEEDS A PREDETERMINED VALUE FROM OTHER PARTICLES WHOSE SHADOW PATTERN PRODUCES A RATIO BELOW THE PREDETERMINED VALUE.
Claim 2
Independent Claim
143 words
A METHOD OF SORTING PARTICLES ACCORDING TO THEIR DEGREE OF TRANSPARENCY COMPRISING THE STEPS OF: PASSING EACH PARTICLE SERIATIM THROUGH A VIEWING ZONE; ILLUMINATING ONE SIDE OF THE PARTICLES TO PRODUCE A SHADOW PATTERN ON A SURFACE IN SAID VIEWING ZONE, THE SHADOW PATTERN OF AT LEAST SOME PARTICLES HAVING A FIRST AREA OF A FIRST LEVEL OF LIGHT ATTENUATION AND A SECOND AREA OF A SECOND LEVEL OF LIGHT ATTENUATION DIFFERENT FROM SAID FIRST LEVEL, EACH OF SAID FIRST AND SECOND AREAS BEING LESS THAN THE TOTAL AREA OF THE SHODOW PATTERN OF SAID PARTICLES, MEASURING THE RELATIVE SIZES OF THE FIRST AND SECOND AREAS OF LIGHT ATTENUATION; AND SORTING THOSE PARTICLES WHICH PRODUCE A SHADOW PATTERN WHOSE RATIO OF FIRST AREA TO SECOND AREA EXCEEDS A PREDETERMINED VALUE FROM OTHER PARTICLES WHOSE SHADOW PATTERN PRODUCES A RATIO BELOW THE PREDETERMINED VALUE.
Claim 3
Dependent Claim
36 words
A method of sorting particles according to claim 1 wherein the first and second areas are measured by taking repeated scans across the shadow pattern of each particle as the particle passes through the viewing zone.
Claim 4
Dependent Claim
21 words
A method of sorting particles according to claim 2 wherein the particles pAss in a free-fall manner through the viewing zone.
Claim 5
Dependent Claim
75 words
A method of sorting particles according to claim 1 wherein the respective areas of first and second levels of light attenuation are measured by scanning across each shadow pattern a plurality of times as the particle passes through the viewing zone, the width of each of the first and second areas is detected during each scan and the detected width of each scan is integrated to give a value of each area of each particle.
Claim 6
Independent Claim
172 words
An apparatus for sorting particles according to the degree of transparency thereof comprising in combination: means for passing each particle seriatim through a viewing means; means for illuminating one side of each particle in said viewing means to produce a shadow pattern on a surface in the viewing means, the shadow pattern of at least some particles having a first area of a first level of light attenuation and a second area of a second level of light attenuation different than the first level, each of the first and second areas of light attenuation being less than the total area of the shadow pattern of said particles; means for measuring the relative size of the first and second areas of light attenuation for each particle in the viewing means; and means for sorting each particle which produces a shadow pattern whose ratio of first area to second area exceeds a predetermined value for other particles which produce a shafow pattern whose ratio of first to second area is below the predetermined value.
Claim 7
Independent Claim
172 words
An apparatus for sorting particles according to the degree of transparency thereof comprising in combination: means for passing each particle seriatim through a viewing means; means for illuminating one side of each particle in said viewing means to produce a shadow pattern on a surface in the viewing means, the shadow pattern of at least some particles having a first area of a first level of light attenuation and a second area of a second level of light attenuation different than the first level, each of the first and second areas of light attenuation being less than the total area of the shadow pattern of said particles; means for measuring the relative size of the first and second areas of light attenuation for each particle in the viewing means; and means for sorting each particle which produces a shadow pattern whose ratio of first area to second area exceeds a predetermined value for other particles which produce a shafow pattern whose ratio of first to second area is below the predetermined value.
Claim 8
Dependent Claim
21 words
An apparatus according to claim 5 wherein the passing means delivers the particles in a free-fall manner to the viewing means.
Claim 9
Dependent Claim
18 words
An apparatus for sorting particles according to claim 5 wherein the illuminating means includes a strip light source.
Claim 10
Dependent Claim
27 words
An apparatus for sorting particles according to claim 7 wherein the measuring means comprises a strip of photosensors aligned to receive light from the strip light source.
Claim 11
Dependent Claim
23 words
An apparatus according to claim 5 wherein the measuring means comprises a strip of photosensors aligned to receive light from the illumination means.
Claim 12
Dependent Claim
99 words
An apparatus for sorting particles according to claim 9 wherein the measuring means further comprises means to scan across the strip of photosensors, each photosensor producing an output signal representative of the value of light received thereby at the time of each scan, and means for counting the output signals representative of the first level of light attenuation and the output of signals representing the second level of light attenuation; and means for comparing the number of signals representative of the first level of light intensity to the number of signals representative of the second level of light intensity.
Claim 13
Dependent Claim
105 words
An apparatus for sorting particles according to claim 10 wherein the comparing means further includes means for integrating the number of signals representative of all photosensors reporting the first level of light attenuation on a plurality of scans as the particle passes through the viewing zone, and for integrating the signals representative of all photosensors reporting the second level of light attenuation on a plurality of scans across the photosensors as the particle passes through the viewing zone; means for operating said sorting means responsive to the integrated ratio of the first level of light attenuation signals to the second level of light attenuation signals.
Claim 14
Dependent Claim
25 words
An apparatus for sorting particles according to claim 11 and further comprising means to divide the number of signals representative of the second light intensity.
Claim 15
Dependent Claim
22 words
An apparatus according to claim 10 and further comprising means to divide the number of signals representative of the second light intensity.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |