Printing Fluid Recirculation for Pigment Suspension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Printing fluids in 2D or 3D printers can experience pigment or particle settling and agglomeration when at rest, leading to flow path blockages and reduced printing quality due to increased viscosity or clot formation.
Innovation Solution
A recirculation system is implemented to circulate printing fluids from the printhead back to the supply, maintaining pigment suspension and providing a cooling effect, using a system with fluid pumps, priming pumps, and valves to manage fluid pressure and flow paths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If printing fluid is kept stationary in the printhead, then printing quality is maintained during active printing, but pigment settling and agglomeration occur leading to flow path blockages
Solution Approach 1:
The patent implements periodic recirculation of printing fluid through the printhead during idle periods. The system activates pumps to circulate fluid back through the printhead at scheduled intervals, preventing pigment settling while maintaining printing quality. This periodic action resolves the contradiction by alternating between stationary (during printing) and circulating (during idle) states.
Solution Approach 2:
The system performs preliminary recirculation actions during idle periods before printing operations begin. By circulating fluid in advance, pigments are kept suspended and ready for immediate printing, preventing blockages before they can form. This preliminary action ensures both printing quality and flow path reliability.
2Reliability
If printing fluid is recirculated continuously, then pigment settling is prevented, but energy consumption increases and temperature control becomes challenging
Solution Approach 1:
Instead of continuous recirculation, the system uses periodic recirculation during idle periods only. Pumps are activated at scheduled intervals rather than continuously, significantly reducing energy consumption while still preventing pigment settling. This resolves the contradiction by providing sufficient circulation to maintain pigment suspension without the excessive energy cost of continuous operation.
Solution Approach 2:
The system maintains pigment suspension through carefully timed recirculation cycles that ensure continuous protection against settling during critical idle periods. By optimizing the timing and duration of recirculation, the system achieves reliable pigment suspension with minimal energy expenditure, avoiding both continuous operation and complete stagnation.
3Reliability
If printing fluid is recirculated, then pigment settling is prevented, but system complexity increases due to additional pumps and valves
Solution Approach 1:
The recirculation system uses the existing printhead structure and fluid pathways for dual purposes: normal printing operation and pigment suspension maintenance. The same nozzles and channels used for printing are utilized during recirculation, eliminating the need for separate dedicated recirculation pathways. This reduces system complexity while maintaining reliable pigment suspension.
Solution Approach 2:
The system uses its own existing components (printhead, fluid pathways) to perform the recirculation function, rather than requiring entirely separate dedicated recirculation equipment. By making the printing system itself serve the dual function of printing and pigment suspension, the patent minimizes additional complexity while achieving reliable pigment maintenance.
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 recirculation system effectively prevents pigment settling, maintains fluid quality, and reduces temperature-related degradation, ensuring consistent printing performance by keeping pigments suspended and regulating fluid temperature.
Implementation Method 1
A recirculation system is implemented to circulate printing fluids from the printhead back to the supply, maintaining pigment suspension
Implementation Method 2
providing a cooling effect, using a system with fluid pumps, priming pumps, and valves to manage fluid pressure and flow paths
Data Source
AI summary
A printing device and method is described comprising: selectively generating a negative fluid pressure between one of one or more printing fluid supplies and a first one of first and second ports of a printhead; selectively generating a positive fluid pressure between one of said printing fluid supplies and a second one of the first and second ports of the printhead; and providing a first pulsed signal to a first priming pump associated with a first one of the first and second ports, wherein the first one of said first and second ports of the printhead is opened under the control of said first priming pump, such that printing fluid within the printhead exits the printhead through the first one of the first and second ports.