Dual Temperature Sensor Fuser Error Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image forming apparatuses face challenges in accurately sensing the temperature of a fuser to prevent overheating and detecting abnormalities in temperature sensors, which can lead to product liability and inefficient operation.
Innovation Solution
The implementation of a dual-temperature sensor system, where a first temperature sensor directly measures the fuser's surface temperature and a second sensor measures ambient temperature to compensate for errors, coupled with a protection circuit that compares sensed and compensated temperatures to detect overheating and sensor abnormalities, ensuring accurate temperature control and preventing fuser overheating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single temperature sensor is used to measure fuser temperature, then the device complexity is low, but the measurement precision and reliability are insufficient due to inability to detect sensor abnormalities
Solution Approach 1:
The temperature sensing function is segmented into two separate sensors: a first temperature sensor for measuring fuser temperature and a second temperature sensor for measuring ambient temperature. This segmentation allows each sensor to perform its specific function optimally while enabling the system to detect abnormalities by comparing the two measurements.
Solution Approach 2:
The second temperature sensor acts as an intermediary reference that provides ambient temperature data. By comparing the first sensor's reading against the second sensor's ambient reference, the system can detect when the first sensor fails or provides erroneous readings, thus improving measurement reliability without directly modifying the first sensor.
2Reliability
If temperature sensor abnormalities are not detected, then the device complexity remains low, but the reliability and safety deteriorate due to potential overheating and product liability
Solution Approach 1:
The protection circuit implements feedback by continuously monitoring the output signals from both temperature sensors and comparing them against each other and against safe operating thresholds. When the first temperature sensor reading exceeds the second sensor reading by more than a predetermined threshold, or when either reading exceeds safe limits, the circuit generates feedback signals to trigger protective actions.
Solution Approach 2:
The protection circuit provides beforehand cushioning by detecting sensor abnormalities before they cause dangerous overheating conditions. The circuit is designed to detect failures in advance and trigger protective measures such as reducing power to the fuser or shutting down the heating element, thereby preventing catastrophic failures and ensuring safety.
3Reliability
If dual temperature sensors with protection circuit are implemented, then the reliability and measurement precision improve, but the device complexity and manufacturing cost increase
Solution Approach 1:
The second temperature sensor serves multiple functions: it provides ambient temperature reference for detecting first sensor abnormalities, acts as a backup temperature reference, and enables the protection circuit to detect both sensor failures and actual overheating conditions. This multi-functionality justifies the additional component by providing multiple safety and monitoring capabilities from a single sensor.
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 enables precise temperature monitoring and control, preventing overheating and detecting sensor abnormalities, thus enhancing the reliability and safety of the image forming apparatus by reducing the risk of product liability and ensuring optimal operation.
Implementation Method 1
a first temperature sensor that directly measures the fuser's surface temperature
Implementation Method 2
a second sensor measures ambient temperature to compensate for errors
Data Source
AI summary
An image forming apparatus including a print engine, a power supply device, a plurality of temperature sensors, and a processor. The print engine including a fuser. The power supply device to selectively provide power to the fuser. The plurality of temperature sensors including a first temperature sensor and a second temperature sensor to sense temperature of the fuser. The processor to control power supplied to the fuser based on a value measured by at least one temperature sensor from among the plurality of temperature sensors. The processor is to identify whether the at least one temperature sensor of the plurality of temperature sensors has an abnormality based on a first measured temperature value and a second measured temperature value of the plurality of temperature sensors.