Intermediate Transfer Member Cleaning With a Pyrolysis Station

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The intermediate transfer member in Liquid Electro-Photographic (LEP) printers is prone to contamination from print agent residue, dust, and machine oil, which significantly reduces print quality.

Innovation Solution

A system and method utilizing a rotatable endless cleaning surface and a pyrolysis station to clean the intermediate transfer member by converting residue to ash, including a rotatable endless cleaning surface that engages with the blanket to transfer residue, moves into a pyrolysis station for heating, and uses ash evacuation components to remove the ash.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the intermediate transfer member is cleaned frequently to maintain print quality, then print quality is improved, but the printing process is disrupted

Engineering Contradiction:
Improveprint qualityVSAvoidprinting process continuity
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The cleaning system performs preliminary cleaning actions during idle periods or between print jobs, preparing the intermediate transfer member for the next printing cycle without disrupting active printing. The system proactively removes residue before it accumulates to problematic levels, maintaining print quality while minimizing interruptions to the printing process.

Inventive Principle:
Principle #10Preliminary action

2Manufacturing precision

If a cleaning system is added to remove residue from the intermediate transfer member, then print quality is improved, but device complexity increases

Engineering Contradiction:
Improveprint qualityVSAvoidcleaning system structure
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical scraping or wiping systems with a thermal field-based pyrolysis system. Instead of using mechanical contact to remove residue, the system uses controlled heating to thermally decompose the residue into volatile components that can be evacuated, thereby simplifying the mechanical structure while achieving effective cleaning.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a heating element as an intermediary between the residue on the intermediate transfer member and the cleaning process. The heating element mediates the transformation of residue from a adhered state to a volatile state, enabling removal without direct mechanical contact and reducing overall system complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of substance

If pyrolysis heating is applied to convert residue to ash, then residue removal is improved, but energy consumption increases

Engineering Contradiction:
Improveresidue removalVSAvoidheating energy consumption
Core Design Contradiction:
Loss of substanceVSUse of energy by moving object

Solution Approach 1:

The system dynamically adjusts the heating temperature and duration parameters based on the type and amount of residue detected. By optimizing these parameters, the system achieves effective pyrolysis and residue removal while minimizing energy consumption, avoiding excessive heating that would waste energy without providing additional cleaning benefit.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Instead of continuous heating, the system applies pyrolysis heating periodically or in pulses during idle periods or between print jobs. This periodic action allows the intermediate transfer member to cool between heating cycles, reducing cumulative energy consumption while still achieving thorough residue removal over time.

Inventive Principle:
Principle #19Periodic action

4Productivity

If the cleaning surface is made rotatable and endless to facilitate continuous cleaning, then cleaning efficiency is improved, but device complexity increases

Engineering Contradiction:
Improvecleaning efficiencyVSAvoidrotatable endless cleaning surface
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The rotatable endless cleaning surface serves multiple functions: it contacts the intermediate transfer member for cleaning, transports the cleaned surface through the pyrolysis heating zone, and provides a continuous working surface for ongoing cleaning operations. This multi-functionality justifies the added complexity by eliminating the need for separate cleaning, heating, and transport mechanisms.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 frequent and continuous blanket cleaning without disrupting the printing process, improving print quality, extending blanket life, and facilitating easy residue collection with minimal consumables.

Implementation Method 1

The pyrolysis station is for receiving the rotatable endless cleaning surface, and is to cause the rotatable endless cleaning surface to be heated to convert the residue to an ash

Methodology Applied
Scientific EffectPyrolysis: Pyrolysis

Implementation Method 2

The pyrolysis station includes a heating element for converting the residue to ash while the rotatable endless cleaning surface is within the chamber

Methodology Applied
Scientific EffectHeating: Heating

Data Source

PatentEP4237911B1Intermediate transfer member cleaning
Publication Date: 2025.10.22 HEWLETT PACKARD DEVELOPMENT COMPANY LP
  • EP4237911B1 patent drawingFigure 1
  • EP4237911B1 patent drawingFigure 2
  • EP4237911B1 patent drawingFigure 3

AI summary

In an example of the disclosure, an intermediate transfer member cleaning system includes an intermediate transfer member ("blanket"), an endless cleaning surface, and a pyrolysis station. The blanket is to receive a thermoplastic print agent from a photoconductive element. The endless cleaning surface can be positioned to rotatably engage with the blanket to transfer a residue of the thermoplastic print agent from the blanket to the endless cleaning surface. The endless cleaning surface can be moved away from the blanket to enter a pyrolysis station. The pyrolysis station is for receiving the endless cleaning surface, for heating the endless cleaning surface to convert the residue to ash, and for removing the ash.