Central Roll Pressure Sensor Integration in Paper Press Nips

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Press arrangements with a central roll and multiple press nips face challenges in accurately measuring pressure distribution due to high costs and complexities of existing pressure sensor systems, leading to potential calibration errors and inefficient pressure measurement.

Innovation Solution

Embedding multiple pressure sensors, such as Bragg grating sensors, within the central roll allows for precise measurement of pressure profiles across multiple press nips as the roll rotates, enabling accurate pressure distribution analysis in a simple and cost-effective manner.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If pressure sensors are installed in each press roller to measure pressure distribution, then measurement precision is improved, but device complexity and cost increase significantly

Engineering Contradiction:
Improvepressure distribution measurementVSAvoidsensor installation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Multiple pressure sensors that would traditionally be distributed across multiple press rollers are merged into a single central roller. The central roller contains all pressure sensors arranged side by side, eliminating the need for separate sensor installations in each press roller while maintaining the ability to measure pressure distribution across multiple press nips.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The central roller serves multiple functions: it forms multiple press nips with different counter-press rollers and simultaneously houses all pressure sensors needed to measure pressure distribution across all press nips. This multi-functional design reduces overall system complexity while maintaining measurement capabilities.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Measurement precision

If multiple pressure sensors are distributed across multiple press rollers, then pressure measurement coverage is improved, but manufacturing cost increases

Engineering Contradiction:
Improvepressure profile measurementVSAvoidmanufacturing cost
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent combines multiple pressure sensors into a single centralized location (the central roller) rather than distributing them across multiple press rollers. This reduces the total number of sensor installation sites and simplifies manufacturing while maintaining comprehensive pressure measurement coverage across all press nips.

Inventive Principle:
Principle #5Merging (Combining)

3Force

If hydraulic pressure is used to drive press rollers, then pressing force is improved, but measurement accuracy deteriorates due to calibration deviations

Engineering Contradiction:
Improvepressing forceVSAvoidpressure measurement accuracy
Core Design Contradiction:
ForceVSMeasurement precision

Solution Approach 1:

The patent replaces the indirect hydraulic pressure measurement system with direct mechanical pressure sensing. Pressure sensors embedded in the central roller directly measure the actual contact pressure in each press nip, eliminating calibration deviations between hydraulic pressure settings and actual pressure distribution.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution enables exact and reliable determination of pressure profiles across each press nip, improving calibration accuracy and reducing operational costs by using a single central roll with embedded sensors, which can differentiate pressure signals based on unique Bragg wavelengths and precise rotational positioning.

Implementation Method 1

The multiple pressure sensors are fiber optic pressure sensors, in particular Bragg grating sensors

Methodology Applied
Scientific EffectBragg grating: Bragg Diffraction

Data Source

PatentEP3149240B1Press arrangement
Publication Date: 2019.08.14 VOITH PATENT GMBH
  • EP3149240B1 patent drawingFigure 1~2
  • EP3149240B1 patent drawingFigure 3

AI summary

The invention relates to a press arrangement (6) for a machine for producing and/or processing a fibrous web, in particular a paper, board, or tissue web, comprising at least one central roller (12) and a first and a second counter pressing unit, wherein the first counter pressing unit forms a first press nip (10) together with the central roller (12) and the second counter pressing unit forms a second press nip (11) together with the central roller (12). The central roller (12) comprises a plurality of pressure sensors (19) embedded in the central roller (12) and arranged adjacently to each other in a machine transverse direction, by means of which pressure sensors the pressure profile in the machine transverse direction in the first and in the second press nip (10, 11) can be determined. The invention further relates to a method for operating such a press arrangement.