Fuser Heater Control via Media-Synchronized On-Off Cycles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fixing devices in electrophotographic image forming apparatuses face variations in fixing performance due to insufficient heating and temperature inconsistencies along the fuser and pressure members, particularly with low-heat capacity equipment, leading to uneven heat distribution and quality issues.
Innovation Solution
A fixing device with a rotatable fuser and pressure member, heated by a controller that adjusts the heater power supply through synchronized on-off switching control cycles, ensuring the equation T1+T2=C*X is maintained, where T1 is the media passage time, T2 is the interval time, C is the control cycle duration, and X is a positive integer, allowing for correction of the duty ratio with a decreasing positive correction factor to stabilize temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If a small-sized, thin-walled fixing roller with low heat capacity is used, then energy efficiency and warm-up time are improved, but temperature uniformity and fixing performance stability deteriorate
Solution Approach 1:
The heater is controlled to operate in periodic on-off cycles synchronized with the conveyance of recording media. The controller turns the heater on during media passage time T1 and off during interval time T2, creating a periodic heating pattern that maintains temperature uniformity while energy is only consumed when needed, thus resolving the contradiction between energy efficiency and temperature stability
Solution Approach 2:
The controller uses feedback from temperature sensing to adjust heater operation timing. By monitoring the thermal state and synchronizing heater activation with media conveyance cycles (T1+T2=C×X), the system maintains optimal temperature uniformity across the fixing roller surface while minimizing energy consumption through precise on-off control
2Temperature
If the fuser roller circumferential length is made longer than the recording sheet, then heat distribution uniformity is improved, but device complexity and manufacturing difficulty increase
Solution Approach 1:
Instead of extending the fuser roller length, the invention uses periodic heating control synchronized with media conveyance. The heater operates in cycles matching T1 (media passage) and T2 (interval), ensuring uniform heat distribution across the roller surface through time-based control rather than spatial extension, thereby avoiding increased manufacturing complexity
Solution Approach 2:
The invention changes the control parameters of the heating system (timing, duration, cycle frequency) rather than changing the physical dimensions of the fuser roller. By adjusting the heater operation parameters to synchronize with media conveyance (T1+T2=C×X), uniform heat distribution is achieved without increasing roller length or manufacturing difficulty
3Reliability
If synchronized on-off switching control is implemented, then temperature stability and fixing performance are improved, but control complexity increases
Solution Approach 1:
The controller implements periodic on-off switching based on the relation T1+T2=C×X, where T1 is media passage time, T2 is interval time, C is control cycle duration, and X is a positive integer. This periodic control pattern synchronizes heater operation with media conveyance, maintaining temperature stability through predictable cyclic operation rather than complex real-time adjustments
Solution Approach 2:
The controller pre-calculates and sets the heater operation timing based on known media conveyance parameters (T1, T2, C, X). By establishing the control pattern in advance according to the synchronized cycle relation, the system achieves temperature stability through predetermined timing rather than complex adaptive control algorithms
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 solution ensures consistent and optimal heat application to recording media, reducing variations in fixing performance and maintaining high-quality imaging by synchronizing heater activation with media conveyance and adjusting for temperature changes, thus enhancing energy efficiency and image quality.
Implementation Method 1
The heater (5) is disposed inside the heat roller (4) to heat the fuser belt (3)
Implementation Method 2
heat from the fuser member causes the toner particles to fuse and melt
Data Source
AI summary
A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween, through which multiple recording media, each spaced apart from each other by an interval distance in a conveyance direction, are sequentially conveyed at a conveyance speed. The heater is disposed adjacent to the fuser member to heat the fuser member. The controller is operatively connected to the heater to control power supply to the heater through a series of on-off switching control cycles, each including an on-time during which the heater power supply is on, and an off-time during which the heater power supply is off, in synchronization with conveyance of the recording medium.