3D Printer Surface Finish Control via Selective Leveling

Solution Overview

Problem

Three-dimensional object printers produce uniformly specular surfaces, which can be undesirable for objects requiring non-reflective or gripping finishes, leading to issues with glare and surface irregularities.

Innovation Solution

A three-dimensional object printer system with multiple ejector heads, a leveling device, and a curing device, controlled by a controller that varies the surface finish by suspending leveling operations near the surface and using modified rendered data to form layers with specific textures, such as anisotropic structures or halftoning, to create diffused or directional gloss finishes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If leveling is performed on every layer to ensure a level foundation, then surface uniformity is improved, but surface finish variety is reduced

Engineering Contradiction:

Improvesurface uniformityVSAvoidsurface finish variety

Core Design Contradiction:

Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The patent applies different surface finish treatments to different regions of the printed object. The leveling device is selectively positioned and operated only in specific areas where a level foundation is needed, while other areas maintain their natural ejected surface texture. This allows the system to provide both uniform surfaces where required and varied finishes where desired, resolving the contradiction between surface uniformity and finish variety.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system dynamically adjusts the leveling operation based on the printing process state. The controller monitors the layer formation process and suspends leveling operations when detecting that the next layer to be formed is within a predetermined number of layers before an exposed surface is formed. This dynamic control allows the system to maintain surface uniformity during critical phases while preserving surface finish variety in final layers, resolving the contradiction between these two requirements.

Inventive Principle:

Principle #15Dynamics

2Manufacturing precision

If conventional leveling is used to create a homogenous finish, then surface uniformity is improved, but glare reduction is worsened

Engineering Contradiction:

Improvesurface uniformityVSAvoidglare

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The patent applies different surface finish treatments to different regions of the printed object. The leveling device is selectively positioned and operated only in specific areas where a level foundation is needed, while other areas maintain their natural ejected surface texture. This allows the system to provide both uniform surfaces where required and varied finishes where desired, resolving the contradiction between surface uniformity and finish variety.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system changes the surface finish parameters by controlling the ejector operation parameters. By modifying the rendered data that controls ejector firing patterns, the system creates surface structures with specific optical properties that reduce glare while maintaining necessary uniformity. This parameter-based control allows differentiation between surfaces that need uniformity and those that need glare reduction.

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If leveling is suspended to create varied surface finishes, then surface finish variety is improved, but surface uniformity is worsened

Engineering Contradiction:

Improvesurface finish varietyVSAvoidsurface uniformity

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent applies different surface finish treatments to different regions of the printed object. The leveling device is selectively positioned and operated only in specific areas where a level foundation is needed, while other areas maintain their natural ejected surface texture. This allows the system to provide both uniform surfaces where required and varied finishes where desired, resolving the contradiction between surface uniformity and finish variety.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The system performs preliminary leveling actions on earlier layers to establish a uniform foundation, then suspends leveling for final layers where surface finish variety is desired. This preliminary action ensures that the base structure maintains necessary uniformity while allowing the final surfaces to exhibit varied finishes, resolving the contradiction between surface uniformity and finish variety.

Inventive Principle:

Principle #10Preliminary action

4Manufacturing precision

If leveling is performed on all layers, then surface uniformity is improved, but productivity is reduced

Engineering Contradiction:

Improvesurface uniformityVSAvoidprinting speed

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

Instead of performing leveling on every single layer (excessive action), the system applies leveling only to the extent necessary - suspending the operation when detecting that the next layer is within a predetermined number of layers before an exposed surface is formed. This partial application of leveling maintains sufficient surface uniformity for structural integrity while eliminating unnecessary leveling operations that would reduce printing productivity.

Inventive Principle:

Principle #16Partial or excessive action

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

Enables the production of three-dimensional objects with varied surface finishes that reduce glare and provide gripping surfaces without introducing noticeable undulations, achieving a more diffuse light reflection and enhanced texture variability.

Implementation Method 1

ejectors fluidly connected to a supply of a material to enable the ejectors to eject material towards the platen

Methodology Applied

Scientific EffectMaterial deposition: Deposition (physical)

Implementation Method 2

a curing device... to operate the plurality of ejectors in each of the at least two printheads to form portions of layers of an object supported by the platen

Methodology Applied

Scientific EffectCuring: Photopolymerisation

Data Source

PatentUS11059225B2Method and system for applying a finish to three-dimensional printed objects

Publication Date: 2021.07.13 GENESEE VALLEY INNOVATIONS LLC

AI summary

A three-dimensional object printer varies the finish in exposed surfaces of a printed object. The printer includes a controller operatively connected to at least two ejector heads, a leveling device, a curing device, and an actuator that is operatively connected to a member to which the at least two ejector heads, the leveling device, and the curing device are mounted. The controller is configured to detect a next layer to be formed being within a predetermined number of layers before an exposed surface is formed, to modify rendered data for the layers within the predetermined number of layers received from the source of rendered data, and to operate a plurality of ejectors in the at least two ejector heads with reference to the modified rendered data to apply a finish to the exposed surface.