Image Forming Apparatus Adaptive Throughput Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heating fixing apparatuses in electrophotographic recording systems face challenges in maximizing throughput while preventing excessive temperature rises that can damage apparatus components, especially when continuously processing small size papers.
Innovation Solution
The image forming apparatus incorporates a system with multiple temperature detecting portions and adaptive conveyance control, which adjusts throughput by changing conveyance speed and interval based on detected temperature thresholds, ensuring the heating member operates within safe temperature limits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the heater operates continuously at high power to maintain target temperature, then the fixing performance is improved, but excessive temperature rise occurs at non-paper feeding portions causing apparatus damage
Solution Approach 1:
The heater is divided into multiple independent heating zones along the longitudinal direction, each controlled by separate temperature detecting members (main thermistor and sub thermistors). This segmentation allows differential power control where paper feeding portions maintain high temperature for fixing while non-paper feeding portions reduce power to prevent excessive temperature rise and apparatus damage.
Solution Approach 2:
Different power control strategies are applied to different regions of the heater. Paper feeding portions (center region) receive full power to maintain target temperature for optimal fixing, while non-paper feeding portions (end regions) receive reduced power when no paper is present, preventing thermal damage to apparatus components without affecting fixing performance in active regions.
2Temperature
If the conveyance speed is reduced to allow temperature control response, then the temperature stability is improved, but the throughput decreases
Solution Approach 1:
The conveyance speed is made dynamically adjustable based on real-time temperature conditions. The control system monitors temperatures at multiple zones and adjusts conveyance speed adaptively: maintaining higher speeds when temperatures are stable and reducing speed only when necessary to prevent excessive temperature rise, thereby optimizing the balance between temperature stability and throughput.
Solution Approach 2:
Temperature detecting members continuously monitor heater temperature and feed this information back to the control system, which adjusts conveyance speed in response to temperature deviations. This feedback mechanism ensures temperature stability is maintained only when necessary, allowing higher throughput during normal operating conditions while preventing excessive temperature rise through responsive speed adjustment.
3Measurement precision
If multiple temperature detecting members are used to monitor different zones, then the temperature control precision is improved, but the device complexity increases
Solution Approach 1:
The temperature monitoring system is segmented into strategic locations (center and ends) corresponding to paper feeding and non-paper feeding zones. This segmented approach provides sufficient temperature control precision for each functional region without requiring continuous monitoring across the entire heater length, balancing measurement precision with device complexity.
Solution Approach 2:
Temperature detecting members are positioned at critical locations where temperature variations most impact performance: the main thermistor at the center monitors paper feeding zone temperature for optimal fixing, while sub thermistors at the ends monitor non-paper feeding zones to prevent excessive temperature rise. This localized monitoring strategy achieves necessary temperature control precision with minimal number of sensors.
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 effectively prevents apparatus damage from excessive temperature rises and maximizes throughput by optimizing conveyance control in response to temperature changes during continuous processing of small size papers.
Implementation Method 1
a heating member, a heating rotating member that is heated by the heating member
Implementation Method 2
the fixing portion fixing the toner image, which has been formed on the recording material nipped and conveyed by the nip, onto the recording material by heating using heat of the heating member
Implementation Method 3
a first temperature detecting portion that detects a temperature at a center of the heating member in a longitudinal direction of the heating member, a second temperature detecting portion that detects a temperature at an end portion of the heating member
Data Source
AI summary
When a toner image is continuously formed on a plurality of recording materials, and the toner image is fixed onto the recording materials, a conveyance control portion changes throughput, which is the number of recording materials to be conveyed per unit time, from first throughput to second throughput, which is slower than the first throughput, when a second detection temperature detected by a second temperature detecting portion that detects a temperature at an end of a heating member in a longitudinal direction of the heating member perpendicular to a conveyance direction of the recording materials exceeds a first threshold, and changes the throughput from the second throughput to third throughput, which is slower than the second throughput, when the second detection temperature exceeds a second threshold, which is higher than the first threshold, after the recording material conveyed at the second throughput reaches the nip.