Pivotable Abutment for Sheet Conveyance Jamming

Solution Overview

Problem

Existing image forming apparatuses face challenges in stabilizing the conveyance and separation of sheets with varying hardness, as the abutment in conventional sheet conveying devices may not effectively manage the conveyance of thick or curled sheets, leading to jamming issues.

Innovation Solution

A sheet conveying device with a pivotable abutment supported by a holder, where a biasing member applies force to move the abutment between an abutting and retracted position, and an adjuster controls the biasing force based on sheet thickness, ensuring proper conveyance and preventing jamming by adjusting the spring pressure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the abutment is made fixed to abut on the sheet conveyance path, then the sheet conveyance is stable for normal sheets, but thick or curled sheets cannot be properly conveyed leading to jamming

Engineering Contradiction:

Improvesheet conveyance stabilityVSAvoidadaptability to sheets of varying thickness

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The abutment is designed to pivot between a first position (abutting on the sheet conveyance path) and a second position (retracted from the path). This dynamic positioning allows the abutment to adapt to sheets of varying thickness - maintaining stable conveyance for normal sheets while retracting to accommodate thick or curled sheets, thereby preventing jamming.

Inventive Principle:

Principle #15Dynamics

2Adaptability or versatility

If the abutment is made movable to accommodate thick sheets, then adaptability to varying sheet thickness is improved, but the conveyance stability for normal sheets deteriorates

Engineering Contradiction:

Improveadaptability to sheets of varying thicknessVSAvoidsheet conveyance stability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The abutment pivots between a first position (abutting on the sheet conveyance path) and a second position (retracted from the path). This dynamic positioning allows the abutment to adapt to sheets of varying thickness - maintaining stable conveyance for normal sheets while retracting to accommodate thick or curled sheets, thereby preventing jamming.

Inventive Principle:

Principle #15Dynamics

3Reliability

If the biasing force is increased to ensure abutment contact, then the conveyance reliability is improved, but the risk of jamming thick sheets increases

Engineering Contradiction:

Improveabutment contact reliabilityVSAvoidjamming of thick sheets

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The abutment pivots between a first position (abutting on the sheet conveyance path) and a second position (retracted from the path). This dynamic positioning allows the abutment to adapt to sheets of varying thickness - maintaining stable conveyance for normal sheets while retracting to accommodate thick or curled sheets, thereby preventing jamming.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The biasing force applied to the abutment is made adjustable through an adjuster mechanism. This allows the biasing force parameter to be optimized - providing sufficient force for reliable abutment contact with normal sheets while preventing excessive force that would cause jamming of thick sheets.

Inventive Principle:

Principle #35Parameter changes

4Reliability

If the abutment is constantly pressed against the conveyance path, then the sheet guidance is improved, but shock and jamming of thick sheets occur

Engineering Contradiction:

Improvesheet guidance accuracyVSAvoidshock and jamming

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The abutment pivots between a first position (abutting on the sheet conveyance path) and a second position (retracted from the path). This dynamic positioning allows the abutment to adapt to sheets of varying thickness - maintaining stable conveyance for normal sheets while retracting to accommodate thick or curled sheets, thereby preventing jamming.

Inventive Principle:

Principle #15Dynamics

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 solution ensures stable conveyance and separation of sheets regardless of thickness, reducing shock and preventing jamming by dynamically adjusting the abutment's position and force in response to the sheet's characteristics, enhancing the reliability of the image forming process.

Implementation Method 1

A biasing member applies a biasing force to the abutment. The biasing force moves the abutment from the retracted position toward the abutting position.

Methodology Applied

Scientific EffectElastic force: Elasticity

Data Source

PatentUS11726425B2Sheet conveying device and image forming apparatus

Publication Date: 2023.08.15 RICOH CO LTD

AI summary

A sheet conveying device includes an abutment that abuts on a sheet conveyance path through which a sheet is conveyed. A holder supports the abutment and pivots to move the abutment between an abutting position where the abutment abuts on the sheet conveyance path and a retracted position where the abutment retracts from the sheet conveyance path. A biasing member applies a biasing force to the abutment. The biasing force moves the abutment from the retracted position toward the abutting position. A restrictor restricts motion of the abutment against the biasing force at the abutting position. An adjuster adjusts the biasing force applied to the abutment situated at the abutting position.