Solid Freeform Fabrication Droplet Merging Dynamics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In solid freeform fabrication, the merging of droplets of modeling and supporting materials during the material jetting process leads to horizontal spreading and mixing, resulting in a deteriorated surface property of the final object due to differing velocity vectors and landing positions, which complicates the removal of the supporting material.
Innovation Solution
The method involves discharging multiple liquid droplets of modeling and supporting materials while the discharging device remains still, allowing the droplets to merge in the air and land on the stage without horizontal vectors, thereby minimizing mixing and improving the surface property of the fabricated object.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple liquid droplets are discharged while moving the discharging device, then fabrication speed is improved, but droplets horizontally spread and mix leading to deteriorated surface property
Solution Approach 1:
The patent applies dynamics by making the discharging device movable during droplet discharge. The device moves in the height direction (Z-axis) during the discharge process, which changes the temporal and spatial characteristics of droplet formation and merging. This dynamic approach allows droplets to merge vertically while minimizing horizontal spreading, thus maintaining surface property while enabling continuous fabrication operation.
2Loss of time
If droplets are merged in the air to form larger droplets, then fabrication time is shortened, but horizontal spreading occurs causing mixing of modeling and supporting materials
Solution Approach 1:
The patent transitions the droplet merging process from horizontal merging to vertical merging by moving the discharging device in the height direction. Instead of merging droplets along the horizontal scanning path, the droplets merge in the vertical dimension during discharge. This dimensional change eliminates horizontal spreading and prevents mixing between modeling material droplets and supporting material droplets, while still achieving the time-saving benefit of merged droplets.
3Productivity
If the discharging device moves during droplet discharge, then fabrication efficiency is improved, but boundary area mixing between materials increases
Solution Approach 1:
The patent uses dynamic movement of the discharging device in the vertical direction during discharge to control droplet formation and placement. This dynamic approach ensures that droplets are discharged and merge primarily in the vertical dimension, maintaining sharp boundaries between modeling material and supporting material regions. The vertical movement compensates for the horizontal scanning motion, preventing material mixing at boundaries while preserving fabrication efficiency.
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 approach enhances the surface quality of the solid freeform fabrication object by reducing the mixing of materials at the boundary area, leading to improved fabrication accuracy and surface properties after the removal of the supporting material.
Implementation Method 1
merging the multiple liquid droplets of the modeling material into a liquid droplet of the modeling material in the air and the multiple liquid droplets of the supporting material into a liquid droplet of the supporting material in the air
Implementation Method 2
the discharging device stands still during at least the discharging to a boundary area of the modeling material and the supporting material on the stage
Implementation Method 3
curing the liquid droplet of the modeling material and the liquid droplet of the supporting material on the stage to form a layered fabrication object
Data Source
AI summary
A method of fabricating a solid freeform fabrication object (17), includes discharging multiple liquid droplets of modeling material and multiple liquid droplets of supporting material to a stage (4) by a discharging device (11;12), merging the multiple liquid droplets of the modeling material into a liquid droplet of the modeling material in the air and the multiple liquid droplets of the supporting material into a liquid droplet of the supporting material in the air, curing the liquid droplet of the modeling material and the liquid droplet of the supporting material on the stage (4) to form a layered fabrication object, and repeating the discharging and the curing to laminate the layered fabrication object (17) to manufacture the solid freeform fabrication object (17), wherein the discharging device (11;12) stands still during at least the discharging to a boundary area of the modeling material and the supporting material on the stage (4).