Sheet Roll Diameter Estimation via Tensioner Position Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for estimating the diameter of a sheet roll in printing apparatuses are inaccurate due to changes in the sheet's posture caused by the tensioner, making it difficult to estimate the roll diameter based on conveyance amount and rotation amount without direct measurement.
Innovation Solution
A sheet conveyor system that includes a holder, rotation measuring device, conveyance roller, tensioner, position detector, and controller, which estimates the sheet roll diameter by combining conveyance amount, rotation amount, and tensioner position data to accurately determine the roll diameter without direct measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the tensioner is used to apply tension to the sheet, then the sheet conveyance is stabilized, but the sheet posture changes making diameter estimation inaccurate
Solution Approach 1:
A position detector is introduced as an intermediary device to detect the tensioner position. This additional measurement channel provides information about sheet posture changes, enabling the controller to compensate for these changes and accurately estimate the sheet roll diameter despite the tensioner-induced posture variations.
Solution Approach 2:
The system implements feedback control by using the position detector to continuously monitor tensioner position and feeding this information back to the controller. The controller then adjusts the diameter estimation based on this feedback, compensating for posture changes and maintaining accurate measurement despite the tensioning action.
2Device complexity
If the diameter is estimated based on conveyance amount and rotation amount, then direct measurement is avoided, but the estimation becomes inaccurate due to sheet posture changes
Solution Approach 1:
The position detector serves as an intermediary measurement device that indirectly provides information about sheet posture without requiring direct contact with the sheet roll. This allows the system to maintain the non-contact estimation approach while improving accuracy through additional positional data.
Solution Approach 2:
The system replaces direct mechanical measurement of the sheet roll diameter with an estimation system based on conveyance amount, rotation amount, and position detection. This substitution uses electrical and optical sensing (position detector) rather than direct mechanical contact, maintaining simplicity while improving accuracy through computational estimation.
3Device complexity
If the tensioner position is not detected, then the system is simpler, but the diameter estimation cannot compensate for posture changes
Solution Approach 1:
The position detector is positioned as an intermediary component between the tensioner and the control system. It provides essential positional information without requiring complex integration with the tensioner mechanism itself, adding minimal structural complexity while enabling accurate compensation for posture changes in the diameter estimation algorithm.
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
Enables accurate estimation of the sheet roll diameter, ensuring precise control and operation of the printing process even when the sheet's posture changes, improving the reliability of the image forming system.
Implementation Method 1
The movable part is displaced upon receiving urging force from an elastic material such as a spring to apply appropriate tension to the sheet
Data Source
AI summary
A sheet conveyor includes: a holder that detachably holds a sheet roll; a rotation measuring device that measures a rotation amount of the sheet roll; a conveyance roller that conveys a sheet pulled out from the sheet roll held by the holder; a tensioner that is provided between the holder and the conveyance roller and that contacts with the sheet pulled out from the sheet roll toward the conveyance roller; a position detector that detects a position of the tensioner; a motor that generates driving force for rotating the conveyance roller; and a controller that controls the motor. The controller estimates a diameter of the sheet roll based on a conveyance amount of the sheet caused by rotation of the conveyance roller, a rotation amount of the sheet roll measured by the rotation measuring device, and a position of the tensioner detected by the position detector.