Sheet Feed Speed Detection for Stack Setting Failure in Printers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sheet conveying devices in image forming apparatuses face challenges in accurately measuring the conveying speed of sheets due to potential misalignment or interference when multiple sheets are fed, leading to reduced accuracy in determining the setting failure state.
Innovation Solution
A sheet conveying device with a lift portion, sheet supply portion, and detection portion that includes an acquisition processing portion to measure the conveying speed of sheets when the stack is lifted, and a determination processing portion to determine the setting failure state based on this speed information, ensuring accurate detection and maintenance timing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple sheets are fed simultaneously, then productivity is improved, but measurement precision of conveying speed deteriorates due to misalignment and interference
Solution Approach 1:
The patent segments the sheet feeding process into distinct phases: a first sheet is fed separately to establish baseline conveying speed, followed by subsequent sheets fed in sequence. This segmentation allows the system to measure conveying speed under controlled single-sheet conditions while still achieving multi-sheet productivity through the continuous feeding of additional sheets after the initial measurement phase.
2Measurement precision
If conveying speed measurement is performed during stack lifting, then measurement timing is optimized, but device complexity increases due to coordination requirements
Solution Approach 1:
The patent merges the conveying speed measurement function with the existing sheet conveying mechanism by utilizing the conveying member and detection portion already present in the system. The measurement is performed during the natural stack lifting operation rather than requiring a separate measurement device, thereby optimizing measurement timing without significantly increasing device complexity.
3Reliability
If setting failure detection is performed continuously, then reliability is improved, but loss of time increases due to frequent measurements
Solution Approach 1:
The patent implements periodic setting failure detection by measuring conveying speed at specific intervals during the sheet feeding process, particularly during stack lifting phases. This periodic measurement approach maintains reliable detection of setting failures while minimizing the total time spent on measurements compared to continuous monitoring, as measurements are taken only when relevant information can be obtained from the natural conveying cycle.
Data Source
AI summary
A sheet conveying device includes a sheet supply portion, a detection portion, an acquisition processing portion, and a determination processing portion. The sheet supply portion supplies an uppermost sheet in a stack of sheets lifted by a lift portion to a conveying path. The detection portion detects the sheet supplied by the sheet supply portion on the conveying path. The acquisition processing portion acquires, when the stack of sheets is lifted by the lift portion, speed information related to a conveying speed of the sheet by the sheet supply portion using the detection portion. The determination processing portion determines whether or not the stack of sheets is in a setting failure state based on the speed information acquired by the acquisition processing portion.