Liquid Ejection Maintenance Unit VOC Capture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current liquid ejection apparatuses are ineffective in significantly reducing the discharge of volatile organic compounds (VOC) due to high printing speeds, leading to concerns about exceeding regulatory discharge limits.
Innovation Solution
A liquid ejection apparatus with a maintenance unit of high airtightness, equipped with multiple filters to capture VOCs, including a filter on the waste liquid container's atmosphere-open side, and a suction unit that rapidly applies negative pressure to the liquid ejection head, directing discharged liquids and gases through a series of filters to minimize VOC emissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a filter is provided only in the exhaust duct, then the structure is simple, but volatile organic compounds are discharged from other openings in the housing
Solution Approach 1:
The filter system is segmented into multiple independent filter units positioned at different locations: one filter in the exhaust duct and additional filters at other housing openings. This segmentation allows VOC capture at multiple discharge points simultaneously, preventing VOC escape from any opening while maintaining modular simplicity in each filter unit's design
Solution Approach 2:
Filter units are introduced as intermediary components between the housing interior and external environment at multiple openings. These filter intermediaries intercept and adsorb VOC molecules before they can escape to the outside, effectively blocking the harmful discharge path without requiring fundamental changes to the housing structure or printing mechanism
2Productivity
If printing speed is increased to high speeds, then productivity improves, but the amount of volatile organic compounds discharged increases
Solution Approach 1:
Filter units are pre-installed at all potential VOC discharge points before printing operations begin. This preliminary preparation ensures that as soon as VOCs are generated during high-speed printing, they are immediately intercepted by the pre-positioned filters, preventing any delay in VOC capture and allowing maximum printing speed without compromising emission control
Solution Approach 2:
The system converts the harmful effect of increased VOC generation from high-speed printing into a manageable challenge by deploying multiple filter units strategically positioned to capture the increased VOC load. The higher VOC concentration generated during fast printing is transformed into a controlled filtration process, where the filters efficiently adsorb the increased amount of VOCs, thereby converting the potential harm of high-speed operation into a solvable filtration task
3Object-affected harmful factors
If multiple filters are provided at different positions, then VOC capture is improved, but device complexity increases
Solution Approach 1:
The filter units are designed as inexpensive, easily replaceable components that can be quickly installed and removed without complex mounting mechanisms. Each filter unit functions as a disposable or periodically replaceable element, allowing multiple filters to be deployed at different housing positions without significantly increasing overall system complexity or cost, as each individual filter unit remains simple and straightforward to maintain
Solution Approach 2:
Filter units utilize porous filtering materials that provide high surface area for VOC adsorption within a compact form factor. This porous structure enables effective VOC capture in small, space-efficient filter units that can be positioned at multiple locations without occupying excessive space or adding significant weight, thereby maintaining relative simplicity in the overall filter system configuration while achieving comprehensive VOC coverage
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 configuration significantly reduces VOC emissions by effectively capturing VOCs within the maintenance unit and preventing their volatilization, ensuring compliance with discharge regulations even at high printing speeds.
Implementation Method 1
a filter for adsorbing the VOC is provided in an exhaust duct of a printer
Implementation Method 2
the suction unit reduces pressure and accumulates negative pressure in the buffer tank, which causes the negative pressure to be rapidly applied to the inside of the cap, and thereby causes the liquid to be discharged from the liquid ejection head
Implementation Method 3
a combustion unit that causes the oxygen of the collected volatile organic compounds to be reacted using a platinum catalyst and to be combusted
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
A liquid ejection apparatus includes: a liquid ejection head having a nozzle which ejects a liquid containing volatile organic compounds to a medium; and a maintenance unit that has a cap, which forms a closed space including an opening of the nozzle, and a suction unit that suctions a fluid from the closed space, and that performs maintenance for discharging the liquid from the nozzle by reducing pressure of the closed space. The maintenance unit is provided with a filter for adsorbing volatile organic compounds contained in the liquid discharged from the liquid ejection head.