Patent US4685569A successfully refreshed from Google Patents.
US4685569A
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Method of detecting and sorting pieces of insulating materials admixed in small pieces of conductive materials
Assignee: Kanzaki Paper Manufacturing Co Ltd
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Filing: 1984-09-17
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Granted: 1987-08-11
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Expires: 2004-09-17
Abstract
Abstract A method of detecting and sorting pieces of insulating materials admixed in small pieces of conductive materials, which comprises detecting and amplifying the surface potentials of the conductive materials and the insulating materials by a surface potentiometer on the basis of a time differentiation method, inputting the signal to a comparator, and sensing the presence of the insulating materials. This method is utilized to detect and sort plastics admixed in pulp and papermaking materials or cereals.
Inventors
- 👤 Shigeyoshi Osaki
- 👤 Shin-ichi Nagata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:00
CPC Classifications
B; B07; B07C; B07C5/00; B07C5/34; B07C5/344; G; G01; G01N; G01N27/00; G01N27/60; B07C2501/00; B07C2501/0036; B07C2501/0054; Y; Y10; Y10S; Y10S209/00; Y10S209/933
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
191 words
A method of detecting and sorting pieces of insulating material admixed in small pieces of conductive material which comprises distributing said material in a thin layer on an electrically conductive surface, conveying said materials forward on said conveying surface, measuring the value proportional to the change of surface charge carried on said materials by means of a surface potentiometer having electrodes disposed above and across the width of said conveying surface, said electrodes being connected via a resistance with an input terminal of a differentiation type amplifier having a feed back resistor connected in parallel therewith, the output current of said amplifier being applied via resistance to a main amplifier having a sensitivity setting element, the output current of said main amplifier being applied to a comparator, inputting said amplified current into said comparator, sending an output signal generated by said comparator to a timer when the voltage of said inputted amplified current exceeds a reference value set in said comparator, and, in response to said output signal received from said comparator, delivering from said timer an output signal according to the set time thereof to effect a subsequent sorting operation.
Claim 2
Independent Claim
191 words
A method of detecting and sorting pieces of insulating material admixed in small pieces of conductive material which comprises distributing said material in a thin layer on an electrically conductive surface, conveying said materials forward on said conveying surface, measuring the value proportional to the change of surface charge carried on said materials by means of a surface potentiometer having electrodes disposed above and across the width of said conveying surface, said electrodes being connected via a resistance with an input terminal of a differentiation type amplifier having a feed back resistor connected in parallel therewith, the output current of said amplifier being applied via resistance to a main amplifier having a sensitivity setting element, the output current of said main amplifier being applied to a comparator, inputting said amplified current into said comparator, sending an output signal generated by said comparator to a timer when the voltage of said inputted amplified current exceeds a reference value set in said comparator, and, in response to said output signal received from said comparator, delivering from said timer an output signal according to the set time thereof to effect a subsequent sorting operation.
Claim 3
Dependent Claim
34 words
The method as claimed in claim 1, wherein a corona discharge is applied to said thin layer of materials distributed on said conveying surface prior to measuring the surface potential carried on said materials.
Claim 4
Dependent Claim
32 words
The method as claimed in claim 1 wherein said materials distributed on said conveying surface are subject to a dust removing operation prior to measuring the surface potential carried on said materials.
Claim 5
Dependent Claim
16 words
The method as claimed in claim 3 wherein said materials are subjected to a vibrating feeder.
Claim 6
Dependent Claim
16 words
The method as claimed in claim 3 wherein said materials are subjected to an air shower.
Claim 7
Dependent Claim
17 words
The method as claimed in claim 3 wherein said materials are subjected to an ionic air shower.
Claim 8
Dependent Claim
31 words
The method as claimed in claim 1 wherein said insulating material is a plastic and said conductive material is one from the group consisting of pulp and papermaking materials and cereals.
Claim 9
Independent Claim
198 words
A method of detecting and sorting pieces of insulating material admixed in small pieces of conductive material which comprises distributing said materials in a thin layer on an electrically conductive conveying surface, conveying said materials forward on said conveying surface, measuring the value proportional to the change of surface charge carried on said materials by means of a surface potentiometer having electrodes disposed above and across the width of said conveying surface, said electrodes being connected via a resistance with an input terminal of a differentiation type amplifier having a feed back resistor connected in parallel therewith, the output current of said amplifier being applied via resistance to a main amplifier having a sensitivity setting element, the output current of said main amplifier being applied to a comparator, inputting said amplified current into said comparator, sending an output signal generated by said comparator to a timer when the voltage of said inputted amplified current exceeds a reference value set in said comparator, and, in response to said output signal received from said comparator, delivering from said timer an output signal according to the set time thereof to cause the movement of the conveying surface to stop for sorting.
Claim 10
Independent Claim
198 words
A method of detecting and sorting pieces of insulating material admixed in small pieces of conductive material which comprises distributing said materials in a thin layer on an electrically conductive conveying surface, conveying said materials forward on said conveying surface, measuring the value proportional to the change of surface charge carried on said materials by means of a surface potentiometer having electrodes disposed above and across the width of said conveying surface, said electrodes being connected via a resistance with an input terminal of a differentiation type amplifier having a feed back resistor connected in parallel therewith, the output current of said amplifier being applied via resistance to a main amplifier having a sensitivity setting element, the output current of said main amplifier being applied to a comparator, inputting said amplified current into said comparator, sending an output signal generated by said comparator to a timer when the voltage of said inputted amplified current exceeds a reference value set in said comparator, and, in response to said output signal received from said comparator, delivering from said timer an output signal according to the set time thereof to cause the movement of the conveying surface to stop for sorting.
Claim 11
Independent Claim
198 words
A method of detecting and sorting pieces of insulating material admixed in small pieces of conductive material which comprises distributing said materials in a thin layer on an electrically conductive conveying surface, conveying said materials forward on said conveying surface, measuring the value proportional to the change of surface charge carried on said materials by means of a surface potentiometer having electrodes disposed above and across the width of said conveying surface, said electrodes being connected via a resistance with an input terminal of a differentiation type amplifier having a feed back resistor connected in parallel therewith, the output current of said amplifier being applied via resistance to a main amplifier having a sensitivity setting element, the output current of said main amplifier being applied to a comparator, inputting said amplified current into said comparator, sending an output signal generator by said comparator to a timer when the voltage of said inputted amplified current exceeds a reference value set in said comparator, and, in response to said output signal received from said comparator, delivering from said timer an output signal according to the set time thereof to cause said materials to be selectively discharged from said conveying surface.
Claim 12
Independent Claim
198 words
A method of detecting and sorting pieces of insulating material admixed in small pieces of conductive material which comprises distributing said materials in a thin layer on an electrically conductive conveying surface, conveying said materials forward on said conveying surface, measuring the value proportional to the change of surface charge carried on said materials by means of a surface potentiometer having electrodes disposed above and across the width of said conveying surface, said electrodes being connected via a resistance with an input terminal of a differentiation type amplifier having a feed back resistor connected in parallel therewith, the output current of said amplifier being applied via resistance to a main amplifier having a sensitivity setting element, the output current of said main amplifier being applied to a comparator, inputting said amplified current into said comparator, sending an output signal generator by said comparator to a timer when the voltage of said inputted amplified current exceeds a reference value set in said comparator, and, in response to said output signal received from said comparator, delivering from said timer an output signal according to the set time thereof to cause said materials to be selectively discharged from said conveying surface.
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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) | 1990-08-10 | 1991-02-09 | 1991-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-10 | 1995-02-09 | 1995-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-10 | 1999-02-09 | 1999-08-11 | $7700.00 | Window Closed / Lapsed |