Fixing Belt Speed Control Using Pressure Roller Expansion Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image forming apparatuses do not effectively estimate the expansion amount of pressure rollers and control their linear velocity to maintain optimal fixing belt operation.
Innovation Solution
An image forming apparatus that includes a fixing member, heater, pressure member, fixing motor, temperature detector, expansion amount estimating section, and controller, which estimates the expansion amount of the pressure roller based on temperature and controls the fixing motor to adjust the linear velocity accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the linear velocity of the pressure roller is not controlled based on expansion amount, then the device complexity is reduced, but the image quality and fixing consistency deteriorate due to sheet slack or tension
Solution Approach 1:
The patent replaces direct mechanical measurement of pressure roller expansion with a thermal model-based estimation system. The expansion amount estimating section calculates expansion based on heater temperature and pre-stored expansion characteristics, substituting complex mechanical sensing with thermal field analysis and computational estimation.
Solution Approach 2:
The patent changes the control parameter from direct mechanical expansion measurement to temperature-based estimation. By using heater temperature as the primary input parameter and applying pre-stored expansion characteristics, the system transforms the control approach from mechanical sensing to thermal parameter monitoring and calculation.
2Manufacturing precision
If the linear velocity of the pressure roller is controlled based on temperature, then the image quality improves, but the measurement precision requirement increases
Solution Approach 1:
The patent creates a virtual model of pressure roller expansion by storing expansion characteristics that correlate temperature with expansion amount. Instead of directly measuring expansion, the system uses this pre-established thermal-expansion model to estimate the current expansion state based on temperature readings, effectively copying the expansion behavior through computational modeling.
Solution Approach 2:
The patent introduces an expansion amount estimating section as an intermediary between temperature measurement and velocity control. This intermediary component processes temperature data through stored expansion characteristics to generate an estimated expansion amount, which then serves as the basis for velocity adjustment, mediating between thermal sensing and mechanical control.
3Measurement precision
If expansion amount estimation is implemented, then the linear velocity control precision improves, but the device complexity increases due to additional control sections
Solution Approach 1:
The patent replaces potential mechanical expansion sensors and direct expansion measurement systems with a computational estimation approach. The expansion amount estimating section uses temperature data and pre-stored characteristics to calculate expansion, substituting mechanical sensing infrastructure with thermal-based computational modeling.
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
Enables precise control of the pressure roller's linear velocity for driving the fixing belt, improving toner image fixation quality by preventing slack or tension in sheets and ensuring consistent image quality across various paper types.
Implementation Method 1
The heater heats the fixing member.
Implementation Method 2
The pressure member applies pressure to the fixing member to form a nip.
Implementation Method 3
The temperature detector measures a temperature of the heater.
Implementation Method 4
The expansion amount estimating section estimates an expansion amount based on a relationship between the temperature and an expansion amount of the pressure member.
Data Source
AI summary
An image forming apparatus (2) includes a fixing belt (240), a heater (241), a pressure roller (242), a fixing motor (243), a temperature sensor (244), an expansion amount estimating section (34), and a fixing motor controller (246). The fixing belt (240) fixes a toner image on a sheet S. The heater (241) heats the fixing belt (240). The pressure roller (242) applies pressure to the fixing motor (243). The fixing motor (243) drives the pressure roller (242). The temperature sensor (244) measures a temperature of the heater (241). The expansion amount estimating section (34) estimates an expansion amount based on a relationship between a temperature of the heater (241) and an expansion amount of the pressure roller (242). The fixing motor controller (246) performs control of driving the fixing motor (243) based on the expansion amount of the pressure roller (242).