Molded Fluid Flow Structure for Printhead Die Assembly

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional adhesive-based assembly processes for inkjet printhead dies become complex and difficult as they shrink in size, limiting the reduction of costs for inkjet pens and print bars.

Innovation Solution

A molded fluid flow structure where the support structure is molded around the printhead die, eliminating the need for adhesives and allowing broader fluid channels that directly supply ink to the die, enabling the use of smaller, thinner, and longer printhead dies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If adhesive-based assembly processes are used for printhead dies, then assembly is possible, but the process becomes complex and difficult as dies get smaller

Engineering Contradiction:

Improveassembly process simplicityVSAvoidassembly process complexity

Core Design Contradiction:

Ease of manufactureVSDevice complexity

Solution Approach 1:

The support structure and fluid flow channels are merged into a single molded component that integrates both structural support and fluid delivery functions, eliminating the need for separate adhesive-based assembly steps

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The molded support structure serves multiple functions simultaneously: it provides mechanical support for the printhead die, forms fluid flow channels, and enables direct fluid delivery without requiring adhesive bonding processes

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Ease of manufacture

If printhead dies are shrunk to reduce cost, then die cost decreases, but adhesive assembly becomes increasingly complex

Engineering Contradiction:

Improvedie costVSAvoidassembly complexity

Core Design Contradiction:

Ease of manufactureVSDevice complexity

Solution Approach 1:

The adhesive-based mechanical assembly system is replaced with a molded integration system where the support structure is formed around the die using compression molding, eliminating adhesive dependency and enabling smaller die sizes

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Volume of moving object

If narrower channels are used to match smaller dies, then die size is reduced, but ink flux decreases and air bubbles block flow

Engineering Contradiction:

Improvedie sizeVSAvoidink flux

Core Design Contradiction:

Volume of moving objectVSProductivity

Solution Approach 1:

The fluid channels are designed to be broader than the die width, creating a dimensional relationship where the channel cross-section exceeds the die footprint, allowing sufficient ink flux while maintaining compact die dimensions

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP3134266B1Fluid flow structure

Publication Date: 2019.10.23 HEWLETT PACKARD DEVELOPMENT COMPANY LP

Figure 1
Figure 2
Figure 3

AI summary

In one example, a fluid flow structure includes a fluid dispensing micro device embedded in a molding having a channel therein through which fluid may flow directly to the device. The device contains multiple fluid ejectors and multiple fluid chambers each near an ejector. Each chamber has an inlet through which fluid from the channel may enter the chamber and an outlet through which fluid may be ejected from the chamber. A perimeter of the channel surrounds the inlets but is otherwise unconstrained in size by the size of the device.