Fluid Reservoir for Inkjet Printers with Dual-Cavity Pressure Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing inkjet printer fluid-supply systems face challenges with air pressurization requiring robust and costly packaging, potential contamination, cavitation issues with fluid pumps, and safety concerns in explosive environments, while also struggling to maintain controlled pressure and ink quality, especially when the packaging is located far from the printer.

Innovation Solution

A fluid reservoir utilizing a suction principle with a pressure-retaining function that allows for the use of 'bag-in-box' packaging, providing controlled pressure without air contact, minimizing cavitation, and separating electrical components from the ink system, enabling operation in explosive environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stress or pressure

If air pressurization is used to supply ink to the printer, then controlled ink pressure is achieved, but the packaging must be robust and expensive to withstand pressurization

Engineering Contradiction:
Improveink pressure controlVSAvoidpackaging robustness
Core Design Contradiction:
Stress or pressureVSStrength

Solution Approach 1:

The system is divided into two separate functional parts: a robust pressure chamber that withstands high air pressure and a separate packaging container that only needs to hold ink. The pressure chamber acts as an intermediary that decouples the pressure control function from the packaging, allowing the packaging to be simple while the pressure chamber provides the required pressure control.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The pressure chamber serves as an intermediary component between the air pressure source and the ink packaging. It receives high-pressure air, regulates the pressure, and transfers it to the ink system without requiring the packaging itself to withstand high pressures. This mediator absorbs the mechanical stress while maintaining controlled ink delivery.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Stress or pressure

If air pressurization is used, then controlled pressure is obtained, but the air may contaminate the ink or cause over-saturation leading to printing problems

Engineering Contradiction:
Improveink pressure controlVSAvoidink contamination
Core Design Contradiction:
Stress or pressureVSObject-affected harmful factors

Solution Approach 1:

The pressure chamber with its sealed design acts as an intermediary that isolates the ink from direct contact with pressurizing air. The chamber provides a controlled environment where pressure can be applied through liquid transmission or regulated air pockets without allowing air bubbles to enter the ink stream, thus preventing contamination and over-saturation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The pressure chamber creates a controlled, inert environment for ink storage and delivery. By sealing the ink in this protected space and using liquid pressure transmission or filtered air pockets, the system maintains an atmosphere that does not contaminate the ink, preventing oxidation, bubble formation, and other air-related degradation.

Inventive Principle:
Principle #39Inert atmosphere (Inert environment)

3Adaptability or versatility

If the packaging is placed far below the inkjet printer, then installation flexibility is improved, but pressure is lost due to elevation difference

Engineering Contradiction:
Improvepackaging placement flexibilityVSAvoidink pressure
Core Design Contradiction:
Adaptability or versatilityVSStress or pressure

Solution Approach 1:

The pressure chamber acts as a pressure boosting intermediary located near the printer. It receives ink from distant packaging under minimal pressure and actively pressurizes it to the required level before delivery. This intermediary compensates for the pressure loss due to elevation, allowing flexible packaging placement while maintaining adequate ink pressure at the print head.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system replaces reliance on passive gravitational pressure with an active pressure control mechanism in the pressure chamber. Instead of depending on the packaging being positioned at a specific height to generate sufficient pressure, the chamber uses regulated air pressure or a small pump to actively maintain the required pressure regardless of packaging location.

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

4Ease of manufacture

If fluid pumps are used to draw ink from packaging, then packaging requirements are reduced, but cavitation occurs creating bubbles that block conduits

Engineering Contradiction:
Improvepackaging simplicityVSAvoidcavitation bubbles
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The harmful cavitation effect is extracted and eliminated by replacing the pump's direct suction action with a pressure-driven flow system. The pump is removed entirely or replaced with a passive pressure equalization mechanism that allows ink to flow without creating the low-pressure zones that cause cavitation. This extracts the problematic function while retaining the beneficial packaging simplicity.

Inventive Principle:
Principle #2Taking out (Extraction)

5Stress or pressure

If pumps and shunts are used to control pressure, then pressure control is achieved, but high shear forces destroy sensitive ink components

Engineering Contradiction:
Improvepressure controlVSAvoidshear forces on ink
Core Design Contradiction:
Stress or pressureVSObject-affected harmful factors

Solution Approach 1:

The system uses pneumatic pressure control through regulated air pressure in the pressure chamber instead of mechanical pumps and shunts. This hydraulic/pneumatic approach provides smooth, controllable pressure without the high shear forces generated by mechanical pumping action. The ink flows under gentle pressure gradients that preserve sensitive components while achieving the required pressure control.

Inventive Principle:
Principle #29Pneumatics and hydraulics

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

This solution allows for environmentally friendly packaging options, maintains ink quality, reduces shear forces, and ensures continuous printing without interruptions, even when the packaging is far from the printer, while keeping the system safe and efficient.

Implementation Method 1

The first cavity (29) is located gravitationally above the second cavity (30)

Methodology Applied
Scientific EffectGravity: Gravitation

Implementation Method 2

a vacuum source (58-60) for creating a pressure difference

Methodology Applied
Scientific EffectPressure difference: Pressure Gradient

Data Source

PatentEP2771191B1Fluid reservoir, a system for fluid supply comprising said reservoir and use of said reservoir in a system for supply of ink to an ink jet printer
Publication Date: 2016.12.07 INKIT
  • EP2771191B1 patent drawingFigure 1~2
  • EP2771191B1 patent drawingFigure 3~4
  • EP2771191B1 patent drawingFigure 5~6

AI summary

The present invention relates to a fluid reservoir (21), said fluid reservoir (21) comprising at least one first cavity (29) and one second cavity (30) in fluidic communication with each other and adapted to accommodate fluid (7), the fluid reservoir (21) further being connected to a fluid-container system (7, 8, 9, 11, 22), a fluid consumer (5) in fluidic communication with at least the second cavity (30), a pressurization system (1, 2) adapted to generate a substantially constant pressure, and a vacuum system (58, 59, 60) adapted to generate a pressure below ambient pressure, the fluid reservoir (21) being designed so that either said pressurization system (1, 2) or said vacuum system (58, 59, 60) can be made to alternately affect the pressure in the first cavity (29), and the fluid reservoir (21) being designed so that said pressurization system (1, 2) can be made to affect the pressure in the second cavity (30), that said vacuum system (58, 59, 60) generates a relative pressure below ambient pressure in the first cavity (29), causing fluid (7) from the fluid-container system (7, 8, 9, 1 1, 22) to flow into the first cavity (29), that said pressurization system (1, 2) causes fluid (7) in the first cavity (29) to flow into the second cavity (30) and generates a feed of fluid (7) to the fluid consumer (5). The invention further comprises a fluid-supply system (64) comprising a fluid reservoir (21) according to the invention, and the use of such a fluid reservoir 21 in a fluid-supply system (64) for inkjet printers.