Patent US6537347B2 successfully refreshed from Google Patents.
US6537347B2
Expired / Lapsed
US
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Method for deciding on the timing of replacing a chemical filter, filter life detection sensor, chemical filter unit, and semiconductor manufacturing apparatus
Assignee: Tokyo Electron Ltd
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Filing: 2002-01-24
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Granted: 2003-03-25
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Expires: 2022-01-24
Abstract
Abstract A chemical filter unit 10 is made of a chemical filter 12 and a filter life detection sensor 1 . The filter life detection sensor 1 is provided with an adsorption state detection sensor 3 and a reference sensor 4 to which a flow of air is blocked. The sensors 3 and 4 are made of the same filter material as the chemical filter 12 with a pair of electrodes sandwiching the filter material. An oscillation circuit, in which the sensors 3 and 4 constitute a part of the oscillating conditions, detects changes in impedance of the sensors 3 and 4 based on the changes in oscillation frequencies. A measurement of the adsorption state detection sensor 3 is corrected with a measurement of the reference sensor 4 in order to remove effects of temperature and humidity, obtain a measurement corresponding to the amount of adsorption of chemical substances, and decide on the timing of replacing the chemical filter based on the corrected measurement.
Inventors
- 👤 Satoshi Motouji
- 👤 Iichi Hirao
- 👤 Teruyuki Hayashi
- 👤 Misako Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:15
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/02; B01D53/04; B01D53/0454; Y; Y10; Y10S; Y10S95/00; Y10S95/90; Y10S95/901
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
123 words
A method for deciding on timing of replacing a chemical filter placed in a ventilation path for removing contaminants from air, comprising: providing sensors constituted of a same material as said chemical filter; and taking a measurement of an impedance of said material constituting said sensors, wherein: an adsorption state detection sensor through which air containing contaminants flows and a reference sensor to which a flow of air is blocked serve as said sensors; said measurement of said impedance of said material constituting said adsorption state detection sensor is corrected with said measurement of said impedance of said material constituting said reference sensor, thereby obtaining a corrected measurement; and said timing of replacing said chemical filter is decided based upon said corrected measurement.
Claim 2
Independent Claim
123 words
A method for deciding on timing of replacing a chemical filter placed in a ventilation path for removing contaminants from air, comprising: providing sensors constituted of a same material as said chemical filter; and taking a measurement of an impedance of said material constituting said sensors, wherein: an adsorption state detection sensor through which air containing contaminants flows and a reference sensor to which a flow of air is blocked serve as said sensors; said measurement of said impedance of said material constituting said adsorption state detection sensor is corrected with said measurement of said impedance of said material constituting said reference sensor, thereby obtaining a corrected measurement; and said timing of replacing said chemical filter is decided based upon said corrected measurement.
Claim 3
Dependent Claim
52 words
A method for deciding on timing of replacing a chemical filter according to claim 1 , further comprising: providing an oscillation circuit including said sensor as a part of oscillating conditions, wherein: said measurement of said impedance is taken based upon an oscillation frequency or an oscillation amplitude of said oscillation circuit.
Claim 4
Dependent Claim
27 words
A method for deciding on timing of replacing a chemical filter according to claim 1 , wherein: said chemical filter is of an activated charcoal fiber type.
Claim 5
Dependent Claim
48 words
A filter life detection sensor constituted of a same material as a chemical filter placed in a ventilation path for removing contaminants from air, comprising: an adsorption state detection sensor through which air containing contaminants flows; and a reference sensor to which a flow of air is blocked.
Claim 6
Dependent Claim
48 words
A filter life detection sensor constituted of a same material as a chemical filter placed in a ventilation path for removing contaminants from air, comprising: an adsorption state detection sensor through which air containing contaminants flows; and a reference sensor to which a flow of air is blocked.
Claim 7
Dependent Claim
52 words
A filter life detection sensor constituted of a same material as a chemical filter placed in a ventilation path for removing contaminants from air, comprising: an adsorption state detection sensor through which air containing contaminants flows; a reference sensor; and an air cleaning reference sensor placed in front of said reference sensor.
Claim 8
Dependent Claim
52 words
A filter life detection sensor constituted of a same material as a chemical filter placed in a ventilation path for removing contaminants from air, comprising: an adsorption state detection sensor through which air containing contaminants flows; a reference sensor; and an air cleaning reference sensor placed in front of said reference sensor.
Claim 9
Dependent Claim
41 words
A filter life detection sensor constituted of a same material as a chemical filter placed in a ventilation path for removing contaminants from air, comprising: a reference sensor; and an adsorption state detection sensor placed in front of said reference sensor.
Claim 10
Dependent Claim
41 words
A filter life detection sensor constituted of a same material as a chemical filter placed in a ventilation path for removing contaminants from air, comprising: a reference sensor; and an adsorption state detection sensor placed in front of said reference sensor.
Claim 11
Dependent Claim
58 words
A chemical filter unit, comprising: a chemical filter for cleaning air; an adsorption state detection sensor which is constituted of a same material as said chemical filter and through which air containing contaminants flows; and a reference sensor which is constituted of a same material as said chemical filter and to which a flow of air is blocked.
Claim 12
Dependent Claim
58 words
A chemical filter unit, comprising: a chemical filter for cleaning air; an adsorption state detection sensor which is constituted of a same material as said chemical filter and through which air containing contaminants flows; and a reference sensor which is constituted of a same material as said chemical filter and to which a flow of air is blocked.
Claim 13
Dependent Claim
66 words
A semiconductor manufacturing apparatus, comprising a chemical filter unit, said chemical filter unit comprising: a chemical filter for cleaning air; an adsorption state detection sensor which is constituted of a same material as said chemical filter and through which air containing contaminants flows; a reference sensor which is constituted of a same material as said chemical filter and to which a flow of air is blocked.
Claim 14
Dependent Claim
66 words
A semiconductor manufacturing apparatus, comprising a chemical filter unit, said chemical filter unit comprising: a chemical filter for cleaning air; an adsorption state detection sensor which is constituted of a same material as said chemical filter and through which air containing contaminants flows; a reference sensor which is constituted of a same material as said chemical filter and to which a flow of air is blocked.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2006-03-24 | 2006-09-23 | 2007-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-03-24 | 2010-09-23 | 2011-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-03-24 | 2014-09-23 | 2015-03-25 | $7700.00 | Window Closed / Lapsed |