Sheet Ejecting Device Air Layer Alignment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional sheet processing devices face challenges in preventing sheets with high surface smoothness, such as coated paper, from cohering due to static electricity, which affects stackability and alignment accuracy.

Innovation Solution

A sheet ejecting device with a blowing unit that aligns sheets orthogonally to their ejection direction and blows air between them to form an air layer, reducing coherence and improving alignment accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If fans are used to blow air onto the back side of ejected sheets to prevent buckling, then buckling in the transfer direction is prevented, but sheets cohere to each other due to static electricity

Engineering Contradiction:

Improvebuckling preventionVSAvoidcoherence due to static electricity

Core Design Contradiction:

ShapeVSObject-generated harmful factors

Solution Approach 1:

A grounded metal plate is introduced as an intermediary between the ejected sheets and the grounding path. This metal plate provides a controlled discharge path for static electricity from the sheets without requiring direct contact between sheets and grounding elements, thereby preventing coherence while maintaining buckling prevention through air blowing

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The mechanical contact-based grounding method is replaced with an electrical field-based grounding system. The metal plate creates an electrical field that facilitates static charge dissipation without mechanical contact, separating the functions of buckling prevention (air blowing) and static discharge (electrical field)

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Productivity

If sheets are stacked closely together to improve space utilization, then productivity is improved, but alignment accuracy deteriorates due to coherence and misalignment

Engineering Contradiction:

ImprovestackabilityVSAvoidalignment accuracy

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The metal plate serves as a mediator that enables close stacking of sheets by providing a common grounding reference. All sheets discharge to the same potential through the plate, preventing electrostatic attraction between adjacent sheets and maintaining alignment accuracy even at high stacking densities

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The electrical potential parameter of the sheets is actively controlled by providing a grounded reference. By maintaining all sheets at the same electrical potential through the metal plate, the sheets remain electrically neutral relative to each other, preventing coherence and preserving alignment accuracy during close stacking

Inventive Principle:

Principle #35Parameter changes

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

The air layer formed between sheets prevents cohering and misalignment, enhancing the stackability and alignment precision of sheets with high surface smoothness.

Implementation Method 1

a blowing unit configured to be provided to the aligning unit and blow a wind toward the ejected sheet

Methodology Applied

Scientific EffectAir layer formation: Air Lubrication

Data Source

PatentUS9533852B2Sheet ejecting device, image forming system, and sheet ejecting method

Publication Date: 2017.01.03 RICOH CO LTD

AI summary

A sheet ejecting device includes: a sheet ejecting unit configured to eject a sheet; a stacking unit on which the sheet that is ejected by the ejecting unit is stacked; an aligning unit configured to align the sheet in a direction orthogonal to the direction in which the sheet is ejected; and a blowing unit configured to be provided to the aligning unit and blow a wind toward the ejected sheet.