Fixing Belt Flange Geometry for Thermal Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fixing devices for electrophotographic image forming apparatuses face challenges such as long warm-up times, poor durability, unstable belt temperature, and issues with separability of recording media due to insufficient abrasion resistance and frictional problems between the fixing belt and ceramic heaters, leading to image displacement and gear damage.
Innovation Solution
A fixing device with a rotatable endless belt, a pressure member, a nip forming member, a reinforcing member, and a flange member that includes a cylindrical support member with a predetermined cross-sectional shape to maintain efficient heating and separability, featuring a heating element that radiates heat to the belt and a flange member that stabilizes the support member's shape and movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a fixing belt is used with ceramic heaters, then heating efficiency is improved, but abrasion resistance deteriorates leading to rough surface and increased friction
Solution Approach 1:
A PTFE (polytetrafluoroethylene) coating layer is introduced as an intermediary between the fixing belt and the ceramic heater. This coating layer has excellent abrasion resistance and low friction characteristics, protecting the belt surface from deterioration while maintaining efficient heat transfer. The PTFE layer acts as a mediator that prevents direct contact wear between the belt and heater, resolving the contradiction between heating efficiency and abrasion resistance.
2Productivity
If a fixing belt is used for high speed printing, then productivity is improved, but warm-up time cannot be shortened
Solution Approach 1:
The PTFE coating layer is applied in advance to the fixing belt surface before operation. This pre-applied coating provides immediate low-friction characteristics and abrasion resistance, allowing the belt to reach operating temperature faster without requiring extended warm-up periods. The coating enables high-speed printing capability while reducing the time needed to reach printable temperature.
3Force
If friction resistance increases due to belt surface roughening, then drive torque increases, but gear damage occurs
Solution Approach 1:
The PTFE coating layer serves as a protective intermediary between the fixing belt and the drive gear. This coating maintains consistently low friction characteristics throughout the belt's operational life, preventing the roughening that would otherwise increase friction resistance and drive torque. By protecting the belt surface, the coating prevents excessive torque transmission to the drive gear, thereby extending gear durability and preventing damage.
4Productivity
If the belt rotates fast, then productivity is improved, but separability of recording medium deteriorates
Solution Approach 1:
The PTFE coating layer acts as a mediator that maintains optimal friction characteristics even at high rotation speeds. This coating prevents excessive friction that would cause the recording medium to adhere to the belt, ensuring clean separability. The low-friction properties of PTFE persist at high speeds, allowing the belt to rotate rapidly while maintaining reliable medium release and preventing image displacement.
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 configuration reduces warm-up time, improves energy efficiency, enhances the separability of recording media, and maintains belt stability, preventing overheating and image displacement issues.
Implementation Method 1
a heating element that radiates heat to the belt
Implementation Method 2
a support member that frictionally contacts an outer circumferential side of the fixing belt in an area corresponding to an area where the fixing belt is heated by the heating element, and supports rotation of the fixing belt
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A fixing device, including a fixing member; a pressure member; a nip forming member; a reinforcing member; a heating member; and a flange member including a cylinder inserted in an inner circumference at an edge of the fixing member in an axial direction thereof and a flange fixed on a frame of the fixing device, wherein the cylinder of the flange member includes a notch storing the nip forming member at a part on the circumference, has an arc-shaped outer circumferential cross-section at an area corresponding to an area where the fixing member is heated by the heating member, having a predetermined radius equivalent to a radius of the fixing member, and the arc has a center located at an upstream side in a recording medium feeding direction relative to a center line of the nip forming member in the recording medium feeding direction.