Secondary Transfer Power Supply Segmentation for Image Forming Apparatus

Solution Overview

Problem

Existing image forming apparatuses face challenges in increasing secondary transfer voltage without incurring significant design constraints, power source size increases, and cost increases due to the need for high voltage transformers and complex wiring arrangements.

Innovation Solution

An image forming apparatus that applies a transfer voltage between an image holder and a transferer using two power sources with opposite polarities, allowing for increased transfer voltage while maintaining compact design and low costs by reversing polarity for each sheet of paper.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If transfer voltage is increased to achieve high productivity, then paper conveyance speed increases, but power source size and cost increase due to high voltage transformer and high voltage wiring requirements

Engineering Contradiction:

Improvepaper conveyance speedVSAvoidpower source size

Core Design Contradiction:

ProductivityVSVolume of stationary object

Solution Approach 1:

The power source is segmented into two separate power sources with opposite polarities. Each power source operates at a lower voltage level, eliminating the need for high voltage transformers and high voltage wiring, thus reducing power source size while maintaining high transfer voltage capability through the combined voltage difference between the two power sources.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of applying high voltage to a single component, the invention inverts the approach by applying low voltage from two power sources with opposite polarities. The transfer voltage is achieved through the voltage difference between the two power sources rather than using a single high voltage source, thereby avoiding high voltage transformer requirements.

Inventive Principle:

Principle #13The other way round (Inversion)

2Productivity

If transfer voltage is increased to achieve high productivity, then paper conveyance speed increases, but design constraints increase due to insulation distance and wiring arrangement requirements

Engineering Contradiction:

Improvepaper conveyance speedVSAvoiddesign constraints

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The power source is segmented into two separate power sources with opposite polarities. Each power source operates at a lower voltage level, eliminating the need for high voltage transformers and high voltage wiring, thus reducing power source size while maintaining high transfer voltage capability through the combined voltage difference between the two power sources.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of applying high voltage to a single component, the invention inverts the approach by applying low voltage from two power sources with opposite polarities. The transfer voltage is achieved through the voltage difference between the two power sources rather than using a single high voltage source, thereby avoiding high voltage transformer requirements.

Inventive Principle:

Principle #13The other way round (Inversion)

3Productivity

If transfer voltage is increased to achieve high productivity, then paper conveyance speed increases, but cost increases due to high voltage transformer and high voltage wiring requirements

Engineering Contradiction:

Improvepaper conveyance speedVSAvoidcost

Core Design Contradiction:

ProductivityVSEase of manufacture

Solution Approach 1:

The power source is segmented into two separate power sources with opposite polarities. Each power source operates at a lower voltage level, eliminating the need for high voltage transformers and high voltage wiring, thus reducing power source size while maintaining high transfer voltage capability through the combined voltage difference between the two power sources.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of applying high voltage to a single component, the invention inverts the approach by applying low voltage from two power sources with opposite polarities. The transfer voltage is achieved through the voltage difference between the two power sources rather than using a single high voltage source, thereby avoiding high voltage transformer requirements.

Inventive Principle:

Principle #13The other way round (Inversion)

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

Enables higher transfer voltage in the secondary transfer process without enlarging the power source or increasing costs, reducing design constraints and preventing paper sheets from clinging together due to balanced electric charge.

Implementation Method 1

a transfer voltage is applied between the intermediate transfer belt and a secondary transfer roller, and the toner image is transferred from the intermediate transfer belt to a sheet of paper

Methodology Applied

Scientific EffectElectrostatic transfer: Electrostatic Induction

Data Source

PatentUS10025235B2Image forming apparatus with power supplies for secondary transfer unit

Publication Date: 2018.07.17 KONICA MINOLTA INC

AI summary

An image forming apparatus includes: an image holder that holds a toner image; a transferer that is disposed opposite to the image holder so as to be in contact with the image holder and transfers the toner image from the image holder onto a recording sheet that is going through a contact part where the transferer contacts the image holder, by applying a transfer voltage between the transferer and the image holder; a first power source that applies a voltage of a first polarity to the image holder; and a second power source that applies a voltage of a second polarity, which is reverse to the first polarity, to the transferer.