Double-Fold Roller Drive Layout for Quiet Sheet Post-Processing

Solution Overview

Problem

Conventional sheet post-processing apparatuses experience issues with speed and quietness due to the driven roller moving away from the driving roller, causing gear pitch variation during the folding process.

Innovation Solution

The apparatus includes a configuration where one of the driving and driven rollers pivots about a pivoting shaft to maintain pressed contact, with direct coupling of the driving shaft to one roller's rotation shaft and indirect coupling via transmission gears to the other roller, enhancing the speed and quietness of the folding process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the driven roller pivots about a pivoting shaft to be pressed against the driving roller via a spring, then the nip portion is formed for folding the sheet, but the driven roller may move away from the driving roller causing gear pitch variation which impairs speed and quietness

Engineering Contradiction:

Improvecontact stabilityVSAvoidfolding speed

Core Design Contradiction:

ReliabilityVSSpeed

Solution Approach 1:

The patent replaces the spring-based mechanical urging system with a motor-driven system. A driving motor is coupled to the pivoting shaft to actively rotate it, replacing the passive spring mechanism. This active control ensures the driven roller maintains pressed contact with the driving roller without the gear pitch variation that occurs with spring-based systems, thereby improving both reliability and speed.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a gear train as an intermediary mechanism between the driving motor and the rollers. The gear train includes a driving transmission gear coupled to the driving motor's driving shaft, and a driven transmission gear coupled to the pivoting shaft. This intermediary gear mechanism transmits power while maintaining synchronized rotation and pressed contact between the driving and driven rollers, eliminating gear pitch variation and improving folding speed and quietness.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the driven roller pivots about a pivoting shaft to be pressed against the driving roller via a spring, then the nip portion is formed for folding the sheet, but the gear pitch varies which impairs quietness of the folding process

Engineering Contradiction:

Improvecontact stabilityVSAvoidnoise

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent replaces the spring-based mechanical urging system with a motor-driven system. A driving motor is coupled to the pivoting shaft to actively rotate it, replacing the passive spring mechanism. This active control ensures the driven roller maintains pressed contact with the driving roller without the gear pitch variation that occurs with spring-based systems, thereby improving both reliability and speed.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a gear train as an intermediary mechanism between the driving motor and the rollers. The gear train includes a driving transmission gear coupled to the driving motor's driving shaft, and a driven transmission gear coupled to the pivoting shaft. This intermediary gear mechanism transmits power while maintaining synchronized rotation and pressed contact between the driving and driven rollers, eliminating gear pitch variation and improving folding speed and quietness.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 apparatus enhances the speed and quietness of the folding process by ensuring the said contact, with direct coupling of the rollers through a gear train, reducing gear pitch variation and improving operational efficiency.

Implementation Method 1

a driving motor, a driving shaft of the driving motor being directly coupled to one of the rotation shaft of the driving roller and the pivoting shaft

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

the other of the rotation shaft of the driving roller and the pivoting shaft being coupled to the driving shaft via a driving transmission gear

Methodology Applied

Scientific EffectGear mechanism: Gear

Implementation Method 3

one of the driving and driven rollers pivoting about a pivoting shaft so as to be pressed against the other

Methodology Applied

Scientific EffectLeverage: Lever

Data Source

PatentEP4674797A1Sheet post-processing apparatus

Publication Date: 2026.01.07 KYOCERA DOCUMENT SOLUTIONS INC

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AI summary

A sheet post-processing apparatus includes a sheet conveyance passage (3, 5, 7) along which a sheet (S) is conveyed and a driving roller (111) and a driven roller (112, 113) that are arranged opposite each other across a folding conveyance passage (102, 106) branching off the sheet conveyance passage (3, 5, 7) and that are kept in pressed contact with each other. The sheet post-processing apparatus double-folds the sheet (S) passing through a nip portion (N1, N2) between the driving and driven rollers (111; 112, 113) and conveys the double-folded sheet (S). The nip portion (N1, N2) is formed with one of the driving and driven rollers (111; 112, 113) pivoting about a pivoting shaft (112b) to be pressed against the other. To one of the rotation shaft (111a) of the driving roller (111) and the pivoting shaft (112b), the driving shaft of the driving motor is directly coupled. The other of the rotation shaft (111a) of the driving roller (111) and the pivoting shaft (112b) is coupled to the driving shaft via a driving transmission gear.