Paper Feeding Roller Clutch Control for Jam Detection Accuracy

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing image forming apparatuses often erroneously detect delays in recording medium conveyance as paper jams, leading to inaccurate jam detection and potential operational disruptions.

Innovation Solution

The implementation of a clutch control mechanism in the paper feeding and registration rollers, which includes a clutch system that switches between conveying and stopping the rotation of the rollers based on control signals, ensuring accurate detection of paper jams and preventing erroneous jam detection by conveying the recording medium a predetermined distance before registration, thereby reducing the likelihood of jam errors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the permissible feeding time is adjusted based on accumulated paper nonfeeding occurrences, then the detection accuracy of paper jams is improved, but the risk of erroneously detecting conveyance delays as jams increases

Engineering Contradiction:
Improvejam detection accuracyVSAvoidoperational reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system performs preliminary conveyance of the recording medium by the paper feeding roller before the image forming operation starts. This preliminary action ensures the medium is properly positioned and engaged, preventing erroneous jam detection during subsequent operations while maintaining accurate jam detection capabilities.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system dynamically adjusts the clutch control state of the paper feeding roller based on operational phase. During the preliminary conveyance phase, the roller is activated; during image forming, the system monitors without activating, allowing distinction between deliberate conveyance delays and actual jams.

Inventive Principle:
Principle #15Dynamics

2Productivity

If the paper feeding roller is activated at the start of image formation, then the recording medium is conveyed properly, but conveyance delay is likely to be erroneously detected as a jam

Engineering Contradiction:
Improveconveyance efficiencyVSAvoidjam detection accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The paper feeding roller performs preliminary conveyance before image forming starts, ensuring the recording medium is already in position and engaged. This eliminates the need to activate the roller at image formation start, thereby preventing conveyance delays from being misinterpreted as jams while maintaining productivity.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If the recording medium is not conveyed upon starting image formation, then erroneous jam detection is reduced, but the paper feeding process is delayed

Engineering Contradiction:
Improvejam detection accuracyVSAvoidconveyance delay
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The system performs the conveyance action in advance during the preliminary phase, so that when image forming starts, the recording medium is already in the correct position. This eliminates both the conveyance delay during image forming and the risk of erroneous jam detection, as the medium is properly engaged before monitoring begins.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP2924507B1Image forming apparatus and image forming method
Publication Date: 2019.03.06 RICOH CO LTD
  • EP2924507B1 patent drawingFigure 1
  • EP2924507B1 patent drawingFigure 2
  • EP2924507B1 patent drawingFigure 3A~3B

AI summary

An image forming apparatus includes a storage unit configured to store a recording medium; a conveyance unit configured to convey the recording medium from the storage unit; an image formation unit configured to perform an image formation for forming an image to be transferred onto the recording medium conveyed from the storage unit; and a detection unit configured to detect a start of the image formation. Upon the detection unit detecting the start of the image formation, the conveyance unit moves the recording medium by a predetermined distance from the storage unit.