Inkjet Print Head Gas Flow Module for Height Variation
Solution Overview
Problem
Ink jet printing at elevated heights above substrates with significant height variations faces issues such as wood-grain defects and sustainability defects due to unsteady air flows and ink accumulation, which affect print quality and stability.
Innovation Solution
A system that includes a print head with nozzles and a gas flow module to provide a controlled flow of gas, such as helium, through the gap between the print head and the substrate, stabilizing the gas flow and reducing defects by mitigating unsteady laminar flows and ink displacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If ink jet printing is performed at elevated heights above substrates with significant height variations, then the ability to print onto substrates with large variations in height is improved, but unsteady air flows cause wood-grain defects and sustainability defects
Solution Approach 1:
A gas flow module is introduced to actively manage the air flow environment in the gap between the print head and substrate. The module includes gas flow nozzles that inject gas to create controlled laminar flow, and suction nozzles that remove excess gas and ink particles. This pneumatic control system stabilizes the air flow to prevent wood-grain defects while maintaining the elevated printing height capability.
Solution Approach 2:
The gas flow module changes the physical parameters of the air flow in the gap by injecting gas at controlled rates and applying suction at specific positions. This modifies the flow velocity, turbulence levels, and pressure distribution to create stable laminar flow conditions that eliminate defects while preserving the ability to print on height-varied substrates.
2Adaptability or versatility
If printing is performed at elevated heights, then printing on substrates with large height variations is enabled, but ink accumulation on the nozzle plate occurs causing sustainability defects
Solution Approach 1:
The gas flow module uses suction nozzles positioned to create negative pressure in the gap region. This suction force actively removes ink particles and excess gas from the gap, preventing ink accumulation on the nozzle plate. The pneumatic system maintains a clean printing environment that eliminates sustainability defects.
Solution Approach 2:
The suction nozzles extract harmful elements (ink particles and excess gas) from the gap between the print head and substrate. By removing these accumulated materials in real-time, the system prevents ink buildup on the nozzle plate and maintains continuous printing capability without sustainability defects.
3Device complexity
If no gas flow control is used, then the system is simpler, but unsteady laminar flows cause wood-grain defects
Solution Approach 1:
The gas flow module introduces pneumatic control elements (gas flow nozzles and suction nozzles) to actively manage air flow stability. This added complexity in the gas flow control system directly addresses and eliminates wood-grain defects by creating stable laminar flow conditions, justifying the increased device complexity through improved print quality.
Solution Approach 2:
The gas flow module creates a controlled feedback system where gas injection and suction work together to maintain stable flow conditions. The suction nozzles respond to and remove disturbances in the air flow, creating a self-regulating system that maintains print quality consistency even with the added complexity of active gas flow management.
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 controlled gas flow reduces wood-grain defects and sustainability issues, improving print quality by maintaining drop momentum and reducing ink accumulation on the nozzle plate, thereby enhancing the stability and consistency of the printing process.
Implementation Method 1
stabilizing the gas flow and reducing defects by mitigating unsteady laminar flows
Implementation Method 2
The gas flow module is configured to provide a flow of low density gas through the gap... maintaining drop momentum
Data Source
AI summary
A system includes a print head including multiple nozzles formed in a bottom surface of the print head. The nozzles are configured to eject a liquid onto a substrate. The system includes a gas flow module configured to provide a flow of gas through a gap between the bottom surface of the print head and the substrate. The gas flow module can include one or more gas nozzles configured to inject gas into the gap. The gas flow module can be configured to apply a suction to the gap.