Nip Plate Rib Height Variation for Wrinkle Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing fixing devices in electrophotography systems cause wrinkles in printed sheets due to a speed difference between the sheet's widthwise ends and middle portion, resulting from uneven pressure distribution during the heating process.
Innovation Solution
The configuration includes a nip plate with ribs of varying heights to distribute loads evenly across the sheet, ensuring consistent pressure and reducing the force difference between the upstream and downstream ends of the nip portion, thereby minimizing wrinkles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If the middle portion of the nip member is offset toward the pressing member to counteract bending, then the nip member maintains contact pressure, but speed difference causes wrinkles on the sheet
Solution Approach 1:
The patent applies local quality by making the nip plate concave in the widthwise direction at its middle portion, creating a localized geometric feature that compensates for bending without offsetting the entire nip member. This localized modification maintains uniform pressure distribution while preventing wrinkle formation.
2Stability of the object's composition
If the nip member is made more rigid to prevent bending, then structural stability improves, but the middle portion cannot flex to maintain contact under pressing member load
Solution Approach 1:
The patent applies curvature by forming the nip plate with a concave shape in the widthwise direction. This curved geometry allows the rigid nip plate to maintain contact with the pressing member under load, as the concave shape enables the middle portion to flex locally while the overall structure remains stable.
3Manufacturing precision
If the nip member is offset to maintain contact pressure, then pressure uniformity improves, but wrinkle formation increases due to speed difference
Solution Approach 1:
The patent solves the problem by transitioning from a one-dimensional offset approach to a two-dimensional solution. Instead of offsetting the nip member in the longitudinal direction, the invention introduces a widthwise concave dimension that allows the middle portion to contact the pressing member while maintaining uniform pressure distribution and preventing wrinkles.
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 design effectively reduces wrinkles by ensuring a more uniform force distribution across the sheet, maintaining image quality and reducing mechanical stress on the printing process.
Implementation Method 1
These structures of the fixing device allow a sheet to be heated by the heater while conveyed between the endless belt and the pressing member
Data Source
AI summary
A fixing device includes an endless belt, a girder disposed inside of a loop of the endless belt and extending in the width direction, a plate disposed between the girder and the endless belt, a pressing member disposed outside of the loop of the endless belt, a heater disposed inside the loop pf the endless belt, a first support disposed between the plate and the girder, and a second support disposed between the plate and the girder while being away from the first support. The first height of the second support is greater than the second height of the second support. A first difference between the first height of the first support and the second height of the first support is less than a second difference between the first height of the second support and the second height of the second support.