Fuser Heater Power Control for Flicker Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrophotographic imaging devices generate significant flicker and harmonics during fusing operations due to large power draws, which can affect health and electronic equipment, and existing solutions fail to adequately reduce these issues without compromising temperature control.
Innovation Solution
A fuser assembly with a heater member and a backup member, equipped with temperature sensors and a power control unit that calculates and adjusts power levels using a power mapping function to select actual power levels that minimize flicker, and independently controls heating elements using predetermined half-cycle waveform patterns to optimize power delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the fuser assembly draws large amounts of power to heat the fuser during fusing operations, then the temperature control performance is improved, but severe harmonics and noticeable flicker are generated
Solution Approach 1:
The patent applies periodic action by using half-cycle waveform patterns to control the heating elements. Instead of continuous power delivery, the system switches power in controlled half-cycles, creating a periodic action that reduces harmonics and flicker while maintaining effective heating. The controller selectively activates heating elements during specific half-cycles of the AC waveform, transforming the continuous heating process into a periodic one that is more harmonically friendly.
Solution Approach 2:
The patent implements dynamics by making the power delivery system adjustable and adaptive. The controller dynamically selects from multiple half-cycle waveform patterns and adjusts the duty cycle based on temperature feedback and power level requirements. This dynamic control allows the system to optimize between temperature control performance and harmonics/flicker reduction in real-time, rather than using a fixed power delivery method.
2Use of energy by moving object
If the fuser assembly draws large amounts of power during fusing operations, then the heating efficiency is improved, but voltage variations are generated which affect the electrical grid
Solution Approach 1:
The system uses periodic half-cycle waveform patterns to deliver power in controlled bursts rather than continuously. This periodic action allows the heating elements to receive sufficient energy for efficient heating while distributing the power demand over time, thereby reducing instantaneous voltage variations on the electrical grid.
Solution Approach 2:
The controller dynamically adjusts the power delivery profile by selecting different half-cycle patterns and duty cycles based on real-time conditions. This dynamic adaptation allows the system to maintain high heating efficiency when needed while reducing voltage variations during grid-sensitive periods, optimizing the balance between heating performance and grid impact.
3Measurement precision
If the power control unit continuously adjusts power levels to maintain temperature control, then the temperature precision is improved, but the complexity of the control system increases
Solution Approach 1:
The control system uses periodic half-cycle waveform patterns with predetermined characteristics stored in memory. Rather than requiring complex real-time calculations for each power adjustment, the controller selects from pre-characterized waveform patterns, simplifying the control logic while maintaining temperature precision through feedback-based pattern selection.
Solution Approach 2:
The system performs preliminary action by pre-storing multiple half-cycle waveform patterns with known characteristics in memory. This allows the controller to select appropriate patterns based on temperature feedback without requiring complex real-time generation or calculation of waveforms, reducing control system complexity while maintaining precision through informed pattern selection.
4Stability of the object's composition
If multiple heating elements are controlled independently to improve temperature distribution, then the uniformity of heating is improved, but the device complexity increases
Solution Approach 1:
The system applies periodic action by controlling multiple heating elements through coordinated half-cycle waveform patterns. Different elements can be activated in different half-cycles or with different duty cycles within the same pattern, enabling independent control for improved temperature distribution while using the periodic framework to manage complexity.
Solution Approach 2:
The controller dynamically adjusts the operation of multiple heating elements based on temperature feedback from sensors. Each element can be independently controlled with different duty cycles and waveform patterns, allowing the system to optimize temperature distribution across the fuser assembly while adapting to real-time thermal conditions.
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 solution effectively reduces flicker and harmonics while maintaining temperature control performance, ensuring compliance with strict geographical requirements and minimizing adverse effects on health and electronic equipment.
Implementation Method 1
The heater member includes at least one heating element
Implementation Method 2
at least one temperature sensor positioned to sense a temperature of the heating element
Data Source
AI summary
An apparatus includes a fuser assembly including a heater member. The heater member includes at least one heating element and at least one temperature sensor to sense a temperature of the heating element. A first power control unit is coupled to the at least one temperature sensor and operative to calculate at least one power level for the at least one heating element based upon at least one set-point temperature therefor and the temperature sensed by the at least one temperature sensor. A second power control unit is coupled to the first power control unit, receives the calculated at least one power level and selects, based upon the calculated power level, at least one actual power level from a stored plurality of predetermined power levels. The second power control unit controls a power for the at least one heating element based upon the selected at least one actual power level.