EP0276106A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for controlling the amount of moisture associated with a web of moving material
Assignee: Voith Paper Automation Inc
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Filing: 1988-01-18
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Granted: —
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Expires: 2008-01-18
Abstract
Abstract A moisture measurement and control system controlling the amount of moisture in paper being manufactured by papermaking machinery, for example, linerboard, utilizes a standard scanning moisture sensor to calibrate a nonscanning moisture sensor to thus provide very fast and accurate moisture measurements for each zone of the moving paper. The measurement is communicated to a fast response time moisture profiler, for example, of the quartz heater type. In addition, the nonscanning moisture measurement unit, which utilizes capacitive electrodes, has improved accuracy due to its electrode arrangement and signal processing technique.
Inventors
- 👤 Pekka M. Typpo
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 19:18
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/22; G01N27/226; G01N27/223; G01N33/00; G01N33/34; G01N33/346; G01R; G01R27/00; G01R27/02; G01R27/26; G01R27/2605
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
171 words
A method using a fixed moisture sensor for controlling the amount of moisture that is associated with a web of moving material where a scanning moisture sensor scans across zones or slices of said web in a cross direction (CD) perpendicular to the machine direction of movement of said web to provide, sequentially, moisture values for each of said zones and also including a moisture profiler for controlling said amounts of moisture in said zones and having a response time much faster than the time required for a single cross direction scan by said scanning moisture sensor, said method comprising the following steps: measuring the amount of moisture in each of said zones substantially continuously by use of a said fixed moisture sensor located at each zone; calibrating said measured moisture by said fixed sensor by comparing with a said moisture value from said scanning moisture sensor to provide a calibration constant; and utilizing said calibration constant by correcting said measured moisture from said fixed sensor to control said moisture profiler.
Claim 2
Independent Claim
171 words
A method using a fixed moisture sensor for controlling the amount of moisture that is associated with a web of moving material where a scanning moisture sensor scans across zones or slices of said web in a cross direction (CD) perpendicular to the machine direction of movement of said web to provide, sequentially, moisture values for each of said zones and also including a moisture profiler for controlling said amounts of moisture in said zones and having a response time much faster than the time required for a single cross direction scan by said scanning moisture sensor, said method comprising the following steps: measuring the amount of moisture in each of said zones substantially continuously by use of a said fixed moisture sensor located at each zone; calibrating said measured moisture by said fixed sensor by comparing with a said moisture value from said scanning moisture sensor to provide a calibration constant; and utilizing said calibration constant by correcting said measured moisture from said fixed sensor to control said moisture profiler.
Claim 3
Dependent Claim
47 words
A method as in Claim 1 where said fixed moisture sensor includes capacitive electrodes and a juxtaposed reference electrode and where said step of measuring said amounts of moisture by said fixed sensor includes the step of differencing signals from said capacitive electrodes and said reference electrode.
Claim 4
Dependent Claim
22 words
A method as in Claim 2, including the step of adding external capacitance to said reference electrode to provide a null signal.
Claim 5
Dependent Claim
24 words
A method as in Claim 2 or Claim 3, including the step of providing a ground plane for said capacitive electrodes for electrical isolation.
Claim 6
Dependent Claim
36 words
A method as in Claim 3 or Claim 4, where said external capacitance is ratioed against a reference electrode to capacitive electrode caoacitance which varies with temperature proportionately with the capacitance of said capacitive electrodes themselves.
References Cited (Backward Citations)
No citation records indexed.
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