Inkjet Printer Bypass Line for Pressure Regulation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Inkjet printers face challenges with air bubbles in printheads, leading to print artifacts and ink wastage due to complex and inefficient fluid distribution systems, especially in larger printheads that require higher ink flow rates and pressure regulation, which is costly and unreliable for multi-color systems.

Innovation Solution

A fluid distribution system with a first container, a connector for the printhead, and a second container that maintains fluid pressure independently of the first container's level, using an umbrella valve and restrictor to control fluid flow, ensuring negative pressure at the printhead nozzles and efficient ink usage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If larger printheads are used to increase print speeds, then productivity is improved, but the required ink supply flow rate increases causing larger pressure drop and changing drop ejection characteristics

Engineering Contradiction:

Improveprint speedVSAvoidpressure drop in ink

Core Design Contradiction:

ProductivityVSStress or pressure

Solution Approach 1:

The fluid distribution system is segmented into multiple independent fluid paths, each with its own pressure regulation. This allows each path to maintain optimal pressure for drop ejection while supplying sufficient flow to larger printhead nozzles, resolving the contradiction between high productivity and pressure stability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A bypass line acts as an intermediary component that provides an alternative fluid path. This bypass line with its own pressure regulation can compensate for pressure drops in the main ink supply path, ensuring stable pressure at the printhead nozzles even when high flow rates are required for larger printheads.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Stress or pressure

If individual pressure regulators are integrated into each printhead, then pressure control is improved, but device complexity and cost increase significantly for multi-color printheads

Engineering Contradiction:

Improvepressure controlVSAvoidnumber of pressure regulators

Core Design Contradiction:

Stress or pressureVSDevice complexity

Solution Approach 1:

The bypass line pressure regulator serves multiple functions: it regulates pressure for the bypass path, compensates for main supply pressure drops, and can independently adjust to maintain optimal pressure at different printhead locations. This multi-functionality reduces the total number of regulators needed while maintaining effective pressure control.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The bypass line is merged with the existing fluid distribution architecture rather than being a completely separate system. This integration allows the bypass pressure regulator to work in conjunction with the main supply system, reducing overall system complexity while maintaining pressure control capabilities.

Inventive Principle:

Principle #5Merging (Combining)

3Manufacturing precision

If air bubbles are removed from printhead, then print quality is improved, but ink consumption increases due to active priming and purging

Engineering Contradiction:

Improveprint qualityVSAvoidink consumption

Core Design Contradiction:

Manufacturing precisionVSLoss of substance

Solution Approach 1:

The bypass line acts as an intermediary path that allows ink to be drawn through the printhead nozzles without requiring active priming or purging operations. This enables air bubbles to be removed more efficiently with lower ink consumption by utilizing the bypass pressure regulation to create appropriate flow conditions.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The system replaces active mechanical priming and purging mechanisms with a passive bypass line pressure-regulated flow system. This substitution reduces ink consumption while maintaining the ability to remove air bubbles from the printhead, improving print quality without the associated ink wastage.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 system simplifies and enhances fluid distribution, reducing ink wastage, improving print quality by maintaining consistent pressure and preventing air bubbles, thus addressing the inefficiencies of existing systems.

Implementation Method 1

the pressure drop in the ink from the ink inlet on the printhead to nozzles remote from the inlet can change the drop ejection characteristics

Methodology Applied

Scientific EffectHydrostatic pressure:

Implementation Method 2

using an umbrella valve and restrictor to control fluid flow

Methodology Applied

Scientific EffectFlow restriction:

Implementation Method 3

ensuring negative pressure at the printhead nozzles

Methodology Applied

Scientific EffectNegative pressure:

Data Source

PatentUS8991955B2Inkjet printer having bypass line

Publication Date: 2015.03.31 MEMJET TECH LTD

AI summary

An inkjet printer includes: an ink container having an outlet port and a return port; a printhead having a first ink port and a second ink port; a first ink line interconnecting the outlet port and the first ink port; a second ink line interconnecting the return port and the second ink port; a bypass line interconnecting the first and second ink lines; a valve system for controlling fluid flow through the first ink line and the bypass line; and a controller for controlling the valve system. During printing, the controller is configured to open the first ink line and the bypass line.