Printhead Filter Membrane Pore Clusters

Solution Overview

Problem

Particulate contamination in printing systems, particularly in printheads with small diameter nozzles, leads to blockages and reduced printing quality, and existing filters often cause significant pressure loss and are difficult to manufacture using MEMS fabrication techniques.

Innovation Solution

A printhead design incorporating a nozzle plate with liquid chambers and a filter membrane featuring pore clusters, where each nozzle is connected to a liquid chamber and a pore cluster, allowing for effective filtration while minimizing pressure loss and facilitating MEMS fabrication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional filters are used to reduce particulate contamination, then printing quality and reliability improve, but pressure loss increases significantly

Engineering Contradiction:

Improveprinting qualityVSAvoidpressure loss

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The filter membrane is segmented into multiple discrete pores arranged in clusters, where each pore acts as an independent filtration element. This segmentation allows the liquid flow to be distributed across many small pathways rather than forced through a single dense filter structure, reducing overall pressure loss while maintaining filtration capability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the filter membrane have different pore densities and configurations. Pore clusters are strategically positioned to provide varying levels of filtration in different areas, allowing optimal balance between particulate removal and pressure drop across the entire filter structure.

Inventive Principle:

Principle #3Local quality

2Reliability

If filters with small pore sizes are used to filter particulates effectively, then printing quality improves, but manufacturing difficulty increases

Engineering Contradiction:

Improveparticulate filtrationVSAvoidmanufacturing difficulty

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The filter is implemented as a porous membrane structure with controlled pore sizes and distributions. This porous material approach enables effective particulate filtration through physical barrier mechanisms while being compatible with various manufacturing techniques including MEMS fabrication processes.

Inventive Principle:

Principle #31Porous materials

Solution Approach 2:

The filter membrane is segmented into multiple discrete pores arranged in clusters, where each pore acts as an independent filtration element. This segmentation allows the liquid flow to be distributed across many small pathways rather than forced through a single dense filter structure, reducing overall pressure loss while maintaining filtration capability.

Inventive Principle:

Principle #1Segmentation

3Reliability

If dense filtration is applied to prevent nozzle blockages, then reliability improves, but pressure drop increases

Engineering Contradiction:

Improvenozzle reliabilityVSAvoidpressure drop

Core Design Contradiction:

ReliabilityVSStress or pressure

Solution Approach 1:

The filter membrane is segmented into multiple discrete pores arranged in clusters, where each pore acts as an independent filtration element. This segmentation allows the liquid flow to be distributed across many small pathways rather than forced through a single dense filter structure, reducing overall pressure loss while maintaining filtration capability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The harmful function of high pressure drop is extracted from the filtration process by separating the filtration function into multiple discrete pore clusters. This allows the beneficial filtration effect to be maintained while removing the adverse pressure loss characteristic through distributed flow paths.

Inventive Principle:

Principle #2Taking out (Extraction)

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 design reduces particulate contamination, maintains high jet straightness, and allows for efficient liquid flow with minimal pressure drop, enhancing printing quality and reliability.

Implementation Method 1

The filter, for example, a filter membrane, includes a plurality of pores grouped in a plurality of pore clusters

Methodology Applied

Scientific EffectFiltration: Filter (physical)

Data Source

PatentUS8534818B2Printhead including particulate tolerant filter

Publication Date: 2013.09.17 EASTMAN KODAK CO

AI summary

A printhead includes a nozzle plate, a filter, and a plurality of walls. Portions of the nozzle plate define a plurality of nozzles. The filter, for example, a filter membrane, includes a plurality of pores grouped in a plurality of pore clusters. Each of the plurality of walls extends from the nozzle plate to the filter membrane to define a plurality of liquid chambers positioned between the nozzle plate and the filter membrane. Each liquid chamber of the plurality of liquid chambers is in fluid communication with a respective one of the plurality of nozzles. Each liquid chamber of the plurality of liquid chambers is in fluid communication with the plurality of pores of a respective one of the plurality of pore clusters. The respective one of the plurality of pore clusters includes two pore sub-clusters spaced apart from each other by a non-porous portion of the filter membrane.