Interleaved Nozzle Array for Gas Impingement Drying
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas impingement units in ink jet printing face inefficiencies in drying or curing treatments and media transport, particularly in cut sheet printers, with high-velocity gas currents causing media lift and increased energy losses.
Innovation Solution
The gas impingement unit employs an array of interleaved nozzles and vent openings that allow gas to escape normally from the media surface, reducing the need for high-velocity cross flows and enhancing media holding force, while incorporating a recirculation system to manage gas flow efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the gas flow rate per surface area of the media is increased to improve drying or curing efficiency, then the curing intensity is improved, but a high-velocity gas current is produced that flows over the media surface and tends to dislocate or lift the media
Solution Approach 1:
The nozzle array is segmented into multiple zones with nozzles directed at different angles (e.g., 0°, 45°, 90°) relative to the media transport direction. This segmentation allows the gas flow to be divided into multiple directional components, enabling effective drying/curing while distributing the gas flow more evenly and reducing high-velocity cross flows that cause media lift.
Solution Approach 2:
Different regions of the nozzle array have nozzles with different orientations tailored to local requirements. For example, nozzles at the leading edge may be directed at different angles than those at the trailing edge, optimizing the drying effect locally while maintaining media stability throughout the entire media surface.
2Productivity
If the gas flow rate is increased to reduce drying time, then the productivity is improved, but the energy losses increase due to high-velocity gas currents
Solution Approach 1:
The segmented nozzle arrangement with multiple angles allows the system to achieve effective drying at lower overall gas flow rates. By directing gas at optimal angles in different zones, the drying efficiency is maximized without requiring high-velocity flows that would waste energy.
3Stability of the object's composition
If a box-shaped nozzle array is used to provide comprehensive gas coverage, then the curing uniformity is improved, but the device complexity and gas flow resistance increase
Solution Approach 1:
Rather than using a solid box-shaped array, the system employs segmented nozzle arrays with multiple angular zones. This segmentation achieves comprehensive gas coverage and uniform curing while reducing the overall gas flow resistance compared to a enclosed box structure, and simplifying the device design.
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 design significantly increases gas flow rate and curing intensity without energy losses, ensuring reliable media transport and reduced paper jams, even without vacuum assistance.
Implementation Method 1
The hot air that has been blown onto the surface of the media transfers a certain amount of heat onto the media
Implementation Method 2
absorbs and carries away the water vapor (in case of water-based ink) that evaporates from the surface of the media
Implementation Method 3
the vent openings are arranged for allowing gas that has been blown out from the nozzles to escape in the direction normal to the support and transport surface
Implementation Method 4
the momentum of the gas that impinges on the media and is then deflected into the vent openings create a force that assists in firmly holding the media on the support and transport surface
Data Source
Figure 1
Figure 2~3
AI summary
A gas impingement unit comprising a gas source (10) and an array (24) of nozzles (20) connected to the gas source (10) and directed onto a support and transport surface (14) arranged for supporting sheet- or web-like media (16) and moving them in a transport direction (A) past the array of nozzles, wherein the nozzles (20) are evenly distributed over an area of the support and transport surface (14), characterized in that said array (24) is an array of interleaved nozzles (20) and vent openings (22), wherein the vent openings (22) are arranged for allowing gas that has been blown out from the nozzles (20) to escape in a direction normal to the support and transport surface (14).