Asymmetric Ejection Guide for Document Skew Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Sheet-feed type image reading apparatuses face document skewing due to uneven transport forces, which can lead to distorted read images, as the transport load on one side of the document is heavier than the other, causing insufficient force on the lighter side.
Innovation Solution
The image reading apparatus employs a transport-force-applying mechanism that applies a greater transport force to one side of the document than the other, with an asymmetrically positioned ejection guide that reduces the transport load on the lighter side, preventing excessive reduction of the transport force and potential distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the transport force applied to the first-directional side of the document is increased to suppress skewing, then the document stability during transport is improved, but the guide excessively reduces the transport force applied to the second-directional side, causing distortion of the read image
Solution Approach 1:
The guide is positioned asymmetrically within the document transport route, specifically located closer to the first-directional side than to the second-directional side. This asymmetric positioning allows the guide to provide necessary support and stability to the document during transport without excessively interfering with the transport force applied to the second-directional side, thereby preventing both skewing and read image distortion
Solution Approach 2:
The guide is strategically positioned only on one side (first-directional side) of the document transport route rather than symmetrically on both sides. This localized positioning provides targeted support where needed while leaving the second-directional side relatively free from excessive transport load, maintaining the balance between document stability and transport force distribution
Data Source
AI summary
An image reading apparatus includes: a document transport route along which a document inserted into the image reading apparatus from a front side is transported backward; a reader that reads an image of the document; an ejection guide that upwardly guides the document being fed after the document is ejected backward from the document transport route; and a transport-force-applying mechanism that applies a transport force to the document. The transport force applied by the transport-force-applying mechanism to a first side of the document is greater than the transport force applied by the transport-force-applying mechanism to a second side of the document, the first side being positioned on a first-directional side in a width direction intersecting a document transport direction, the second side being positioned a second-directional side that is opposite to the first-directional side. The ejection guide is positioned asymmetrically toward the first-directional side in the width direction.