The present invention is directed towards methods and apparatus for handling powder in a 3D printer. The invention includes a means of transporting powder from multiple sources to a powder dispensing apparatus with minimal user intervention, thus reducing contamination of the 3D printer and surrounding area with loose powder, while also providing a means of improving the recycling of powder for re-use.

Apparatus and methods for handling materials in a 3-d printer

Apparatus for producing an object by sequentially forming thin layers of a construction material one on top of the other responsive to data defining the object, the apparatus comprising: a plurality of printing heads each having a surface formed with a plurality of output orifices and controllable to dispense the construction material through each orifice independently of the other orifices; a shuttle to which the printing heads are mounted; a support surface; and a controller adapted to control the shuttle to move back and forth over the support surface and as the shuttle moves to control the printing heads to dispense the construction material through each of their respective orifices responsive to the data to form a first layer on the support surface and thereafter, sequentially the other layers; wherein each printing head is dismountable from the shuttle and replaceable independently of the other printing heads.

Rapid prototyping apparatus

Methods, devices and systems for efficient 3D printing that address conventional inefficiencies while utilizing a single compact device are set forth. Some embodiments utilize a circular-shaped build area revolving symmetrically around a single center point utilizing a continuous helical printing process. In one embodiment a liquid photopolymer for solidification is deposited on a build platform to form the physical object The Build platform is continuously rotated and simultaneously raised in a gradual programmed manner. Focused from below the platform produces a single continuous “layer” of material deposited and bonded in a helical fashion.

3D Printing Using Spiral Buildup

Fused Filament Fabrication (FFF) is the process of 3D printing objects from melted plastic filament. The hot plastic exits a nozzle and fuses with the part just below, adding a layer of material to the object being formed. However, filament can only be deposited on top of an existing surface. Therefore, overhangs require a disposable support structure to be printed, temporarily supporting the threads of plastic that would otherwise hang in empty space. Existing techniques for support generation fall into two categories: The first allow for very reliable prints by enclosing the bottom of the object in a dense structure, at the expense of increased material usage and build times. The second generate thin hierarchical structures connecting to the surface in a sparse number of points. This uses less material, at the expense of reliability: the part might become unstable, the structure itself may become difficult to print, the bottom surface quality degrades. The user therefore has to correct the structure and its parameters for each new object. We propose to exploit the ability of FFF printers to print bridges across gaps. Since bridges are always supported by pillars at their extremities, they are both stronger and more stable than hierarchical tree structures. Our technique first selects the points to support based on overhang and part stability during the entire print process. It then optimizes for a printable scaffolding composed of bridges and vertical pillars, supporting all points. The result is an automated support generation technique using little material while ensuring fine surface quality and stability during the printing process.

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Bridging the gap: automated steady scaffoldings for 3D printing

Devices, systems and methods for three-dimensional model printing. A three-dimensional model printer may, for example, calibrate, optimize, or indicate the need for replacement of or evaluation of one or more printing heads or nozzles of the three-dimensional model printer.

Device, system and method for calibration in three-dimensional model printing

A method for printing and supporting a three-dimensional (3-D) object is provided. The method of printing can include dispensing a first interface material for the construction of the three-dimensional object, dispensing a second interface material to form a support structure for supporting the three-dimensional object and dispensing a third interface material which may be used to separate the support structure from the 3-D object Disclosed also a method for producing a 3-D model containing various kinds of inserts.

Elisha Kritchman

Papers

System and method for printing and supporting three dimensional objects