Doctor Blade Holder Profiling Plate for Non-Uniform Roll Pressure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional doctor blade holders struggle to make precise adjustments on non-uniform roll surfaces, such as Yankee rolls, leading to inconsistencies in blade positioning and pressure distribution, which can cause blade chatter and vibration.

Innovation Solution

A doctor blade holder system with a profiling plate and adjustment mechanisms that allow for small localized adjustments, using spherical mounting arrangements and clamping bars to maintain precise contact with the roll surface, accommodating variations in roll diameter and ensuring even pressure distribution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If adjustment screws are provided at spaced apart locations to adjust doctor blade position, then the doctor blade can be positioned closer to the roll surface at specific locations, but this introduces inconsistencies in pressure distribution and compromises other portions of the doctor blade holder

Engineering Contradiction:
Improvedoctor blade position accuracyVSAvoidpressure distribution uniformity
Core Design Contradiction:
Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The patent employs a flexible doctor blade holder that can dynamically adapt its shape to match the contour of the roll surface. The flexibility allows the holder to conform to diameter variations along the roll length, enabling uniform pressure distribution across the entire blade contact area while maintaining precise positioning capability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the physical state of the doctor blade holder from rigid to flexible, allowing it to deform and adapt to the roll surface profile. This parameter change enables the holder to maintain consistent contact pressure across varying roll diameters without requiring multiple adjustment points that would create pressure inconsistencies.

Inventive Principle:
Principle #35Parameter changes

2Stability of the object's composition

If the doctor blade holder is made rigid for stable mounting, then mounting stability is improved, but the ability to accommodate non-uniform roll surfaces is reduced

Engineering Contradiction:
Improvemounting stabilityVSAvoidroll surface accommodation
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The doctor blade holder transitions from a static rigid structure to a dynamic flexible structure that can adapt its shape while maintaining stable mounting. The flexibility is designed to allow controlled deformation along the length of the holder, enabling it to follow the roll surface contour while remaining firmly mounted.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent utilizes a flexible doctor blade holder that acts as a compliant element between the rigid mounting structure and the non-uniform roll surface. This flexible component absorbs the geometric variations of the roll while maintaining stable mounting connections at the ends, effectively decoupling mounting stability from surface adaptability.

Inventive Principle:
Principle #30Flexible shells and thin films

3Manufacturing precision

If multiple adjustment mechanisms are added to accommodate roll diameter variations, then positioning accuracy on non-uniform surfaces improves, but device complexity increases

Engineering Contradiction:
Improveblade-to-roll contact precisionVSAvoidadjustment mechanism complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent extracts the adjustment function from multiple discrete adjustment mechanisms and consolidates it into the inherent flexibility of the doctor blade holder itself. The flexible holder naturally adapts to roll surface variations without requiring active adjustment mechanisms, thereby reducing device complexity while maintaining positioning precision.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The flexible doctor blade holder performs self-adjustment by passively conforming to the roll surface profile through its flexibility. This self-service capability eliminates the need for complex external adjustment mechanisms, as the holder automatically adapts to diameter variations along the roll length through its inherent mechanical properties.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3425111B1Doctor blade holder system
Publication Date: 2023.05.17 KADANT INC
  • EP3425111B1 patent drawingFigure 1
  • EP3425111B1 patent drawingFigure 2
  • EP3425111B1 patent drawingFigure 3

AI summary

The invention provides a doctor blade holder system that includes a doctor blade support structure, an adjustment profiling plate, and a series of adjustment mechanisms. The doctor blade support structure includes an elongated slot for receiving a doctor blade and a separate elongated slot to house mounting hardware. The adjustable profiling plate causes pressure to be applied to the working blade in a continuous manner along the length of the working blade, wherein the profiling plate is mounted to a holder mounting plate with a series of pairs of mounting structures allowing unconstrained flexure, or rotation, of the profiling plate with respect to holder mounting plate around two axes. The series of adjustment mechanisms attach to the holder mounting plate and acting on the profiling plate, wherein the adjustment mechanisms are capable of displacing the profiling plate in a bi-directional manner.