Bernoulli Force Rollers for Inkjet Media Wrinkle Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In digitally controlled inkjet printing systems, the expansion and contraction of receiver media due to moisture introduction lead to wrinkles, which affect image quality, and existing solutions fail to provide adequate traction and stability, especially when minimal wrap is possible around guiding rollers.
Innovation Solution
A wrinkle-reduction system using media-guiding rollers with grooves and air sources to create a Bernoulli force, drawing the media toward the roller surface, providing increased traction and stability, and allowing for lateral stretching and steering of the media.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the receiver media is advanced through the system with contact between the receiver media and contact surface of rollers, then the receiver media is guided through the printing system, but friction between the receiver media and rollers prevents the receiver media from sliding freely in the cross-track direction, resulting in localized buckling and wrinkles
Solution Approach 1:
The patent employs an air bearing system where pressurized air is supplied through porous material or holes in the roller contact surface. This creates a thin air cushion between the receiver media and the roller, eliminating direct mechanical contact and friction. The air bearing allows the media to float smoothly over the roller surface while maintaining precise positional control, thereby preventing wrinkles and flutes from forming during transport through the printing system.
2Quantity of substance
If drying is used to remove moisture from the receiver media, then moisture content is reduced, but dimensional characteristics of the receiver media change, adversely affecting image quality
Solution Approach 1:
The patent modifies the drying process parameters by controlling the temperature, air flow rate, and exposure time to achieve moisture removal while minimizing dimensional changes. By optimizing these parameters, the system effectively reduces moisture content to prevent wrinkles during media expansion and contraction, while maintaining the dimensional stability required for high-quality image production.
3Device complexity
If minimal wrap is used around guiding rollers, then the printing system design is simplified and space is reduced, but adequate traction and stability are not provided, leading to increased wrinkles and fluttering
Solution Approach 1:
The air bearing system enables minimal wrap around guiding rollers while maintaining adequate traction and stability. The pressurized air cushion provides continuous support and control over the receiver media, preventing wrinkles and fluttering even when the media wraps only a small portion of the roller. This pneumatic support mechanism allows the system to achieve both simplified design with minimal wrap and reliable media control.
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
The system effectively reduces wrinkles and fluttering, maintaining image quality by ensuring sufficient traction and stability even with minimal wrap, and can steer the media to prevent cross-track drift.
Implementation Method 1
an air source for providing an air flow into the grooves in the media-guiding roller, the air flow being directed between the first side of the media and the exterior surface of the media-guiding roller thereby producing a Bernoulli force to draw the media toward the exterior surface of the media-guiding roller
Data Source
AI summary
A wrinkle-reduction system includes two media guiding rollers located in proximity to first and second edges of a media, each media guiding roller having a corresponding roller axis and having one or more grooves formed around its exterior surface. The media travels along a transport path past the media-guiding rollers with a first side of the media facing the exterior surface of the web-guiding rollers. Air sources provide an air flow into the grooves in the media-guiding rollers, the air flow being directed between the first side of the media and the exterior surface of the media-guiding rollers thereby producing a Bernoulli force to draw the media toward the media-guiding rollers. The first roller axis is not parallel to the second roller axis such that when the air sources are activated the media guiding rollers impart a lateral stretching force to the media in the cross-track direction.