Invented by Aaron Barclay, Peter D. Schuller, Jordan Paul Nadeau, Shawn Michael Koop, Stratasys Inc
The Stratasys Inc invention works as followsA 3D printer includes a gantry configured for movement in a plane substantially parallel with a build plane. The system comprises a platen configured for supporting a part that is being built layer by layer, the platen being configured to move substantially in the direction normal to the build plan. The system comprises a head carriage supported by the gantry, wherein the carriage has a first member that supports a retaining device. The retaining device includes at least one extension from the support and a camming element that is rotatably mounted to the support and can be moved around an axis. The camming element has an arcuate camming face with increasing radial distances from the axis. The system comprises at least a print head with a housing that has a first surface to engage at least one member, and a secondary surface to engage arcuate camming surfaces. The camming members can be positioned between a non-engaging first position, where the atleast one print head is removed from the support member, and an engaging second position, where the camming members engages the second face of the print heads and the first face of the print heads engages at least one member, causing a frictional contact therebetween.
Background for 3D printer coupling to attach print head to carriage
The present disclosure is a system for additive manufacturing that prints three-dimensional (3D), parts and supports structures. The present disclosure is a coupling that allows a printhead to be attached and detached from a carriage head in a 3D printer.
Additive Manufacturing, or 3D Printing, is a general process where a 3D object is created by adding material rather than subtracting it as is done in traditional machining. An additive manufacturing system’s basic operation is to slice a 3D computer model into thin sections, translate the results into 2D position data and feed the data into control equipment that manufactures a 3-dimensional structure using an additive build style. Additive Manufacturing encompasses a variety of methods for fabrication. These include fused deposition modelling, ink jetting, selective laser melting, powder/binder jetting and stereolithographic techniques. “Using one or more of these additive manufacturing techniques, an additive manufacturing system (commonly known as 3D printer) can print a solid three-dimensional object in virtually any shape from a digital representation of the object.
In a fused-deposition-modeling additive manufacturing system, the printed part can be built from a digital model of the part by extruding flowable material along toolpaths. The material is extruded by an extrusion head carried by the print head and deposited onto a substrate as a series of roads. The extruded material is fused to the previously deposited material and solidifies when temperature drops. The position of the printhead relative to the substrate after each layer has been formed is increased along an axis perpendicular to build plane.
In the fabrication of printed parts using layers of part material, support layers or structures will be built under overhanging parts or in cavities that are not supported by part material. The same techniques used to deposit the part material can be used to build a support structure. The host computer creates additional geometry that acts as a supporting structure for overhanging or empty-space segments in the printed part. The support material is then deposited by a second nozzle in accordance with the generated geometry. The support material adheres during fabrication to the material of the part, but is easily removed from the printed part after the printing process has been completed.
An aspect relates to the 3D printer with a gantry that is configured to move along a plane parallel to a building plane. The system includes an edging platen that is designed to support the part as it is built layer by layer. The system includes a head-carrier carried by the gantry, wherein the carriage has a support member that carries a retaining device configured to accept a removable printhead. The retaining device includes at least one extension from the support element and a camming component rotatably mounted to the support element and movable around an axis. The camming element has an arcuate surface that increases in radial distance away from the axis. The camming surface is movable between two positions: a non-engaging one where the print head can be removed from the support member, and an engaging second position, where the camming surface engages with the second surface of the print head, and the first surface of that print head engages at least one of the members and causes frictional engagement.
Another aspect” of the disclosure is a 3D-printer with a gantry that moves in a plane parallel to the build plane. The system comprises a platen that is designed to support an object being built layer by layer, and the platen can move in a direction that is substantially normal to a build plane. The system includes a gantry that supports a head carriage. On the head carriage, there is a support member with a first retention mechanism. The first retaining device includes a support member with a first pin and a support member with a second pin, where the second pin is offset from the first pin. The first retaining device includes a camming element that is rotatably attached between the first pin, and the second pin. It is laterally offset to the first and second pins. The camming element has an arcuate camming face with an increasing radial separation from the axis. The system comprises at least one printing head, with a housing that has a first surface to engage both the first and second pins and a second surface to engage an arcuate camming area. The camming element is movable between two positions: a non-engaging first position, where the atleast one printhead is removed from the support member, and a second engaging position, where the camming element engages the second surface of the printhead and the first pin engages both the first and second sides of the printhead, resulting in a frictional contact.
The 3D printer can include a support member with a second retaining mechanism that is essentially a mirror of the first system. The system can include a second head with a configuration that is similar to that of the first head. Both the first head and the second head may have securing features located on their first and/or second sides, so that they can be attached to the carriage using either the second or first retaining system.
The following terms, unless otherwise specified, have the meanings given below.
The terms “preferred”, “preferably”, and “example” are used. “The terms ‘preferred?, ‘preferably?,?example? and?exemplary?” Refers to certain embodiments of an invention that could provide certain benefits under certain circumstances. Other embodiments can also be exemplary or preferred, depending on the circumstances. The recitation or one or more exemplary or preferred embodiments is not meant to imply other embodiments as not being useful or exclude them from the scope.
Directional orientations, such as ‘above’, ‘below?, top?, bottom? and the like, are made in reference to a layer printing direction of a 3-D part. In certain embodiments, the layer printing direction is along the vertical Z-axis. The terms “above”, “below”, “top”, and so on are used in these embodiments based on the vertical Z-axis. In embodiments where the 3D part layers are printed along another axis (such as a horizontal x or y axis), the terms “above”, “below”, “top”, and “bottom” are relative to that axis.
The terms “about” and “substantially? The terms?about? “The terms “substantially” and “measurable values” are used in this document to describe measurable values or ranges that can be expected due to known variations in the field (e.g. limitations and variability in measurements).
All patents, publications and other documents cited herein have been incorporated as references.
The present disclosure is a mechanism to mount a printhead on a head-carrier carried by an additive manufacturing system (commonly known as a 3D Printer). The present disclosure comprises a head carriage with left and right retaining mechanisms that frictionally secure first and second prints heads to the carriage. The retaining mechanism frictionally engages the left and the right print heads to substantially prevent movement in the x y z planes and pitch, roll, and yaw relative the head carriage.
The present disclosure has many advantages over the receptacle-based retaining system that used a physical interference fitting to mount the printhead to the carriage. The present disclosure has a simpler design which leads to greater reliability. The complexity has been reduced, so there are fewer components, and no precision parts, as compared to prior receptacle-based designs. This results in a more reliable connection between the printhead and the carriage.
Furthermore, the present disclosure permits close placement of print heads and, therefore, a more compact configuration for the head and a smaller footprint overall. When two print heads were positioned side by side in the receptacle-based retaining system of prior art, the adjacent sidewalls of the receptacles would displace the heads at least the thickness of two adjacent sidewalls. The present disclosure is advantageous because it allows multiple print heads, either side by side or close together, to be mounted to the carriage without requiring a receptacle. The packing density for print heads using the disclosed retaining mechanism is higher than the previous receptacle-style designs.
The interface disclosed between the printhead and carriage can be used in any new 3D Printer. “Also, 3D printers from the past can be retrofitted with the disclosed print head and carriage.
The present disclosure can be used with any extrusion-based 3-D printer. As an example, FIG. The 3D printer 10 shown in Figure 1 has a print plane that is substantially horizontal. The part being printed is indexed in the direction of a vertically oriented part as it is printed layer by layer using two print heads, 18A and 18B. The 3D printer 10 illustrated uses two consumables assemblies 12. Each consumable assembly 12 is a container device that can be easily loaded, removed, and replaced. It contains a supply for a consumable material to print with system 10. One of the consumables 12 typically contains a filament for a part, while the other contains a filament for a support. Each consumable 12 supplies filament to a print head 18A, 18B. Both consumable assemblies 12 can have the same structure. The consumable filament may be retained on a wound coil, a coil-less coil or another supply arrangement as described in Swanson and others, U.S. Pat. No. 8,403,658; Turley et al. U.S. Pat. No. No. 7,063,285: Taatjes et al., U.S. Pat. No. 7,938,356; and Mannella et al., U.S. Pat. Nos. Nos.
Each printhead 18A and18B is a removable, easily replaceable and loadable device that comprises a housing which retains a Liquefier Assembly 20 with a nozzle 14. Each print head 18A or 18B is configured for receiving a consumable, melting the material in the liquefier 20 to produce a liquid material and depositing the liquid material through a nozzle 14 of the liquefier 20. Swanson et. al., U.S. Pat. No. 6,004,124; LaBossiere, et al., U.S. Pat. No. 7,604,470; Leavitt, U.S. Pat. No. 7,625,200; and Batchelder et al., U.S. Pat. No. 8,439,665. Patent Publication Nos. Other suitable liquefier assemblies include those disclosed in U.S. Patent Publications Nos. WO2016014543A.
Guide tube (16) interconnects consumable assemblies 12 and print heads 18A or18B. A drive mechanism of print heads 18A or18B (or 3D printers 10) draws successive segments from consumable assemblies 12, through guide tubes 16, to the liquefier 20 assembly of print head 18.A or 18.B. In this embodiment, the guide tube 16 is a part of system 10 and not a sub-component. In other embodiments guide tube 16 may be a component of consumable assemblies 12 and can be exchanged from and to system 10 for each consumable assembly. During the build process, the segments of consumable material that are driven through print heads 18A and 18B are heated in liquefier 20. The material is then extruded in layers through the nozzle tip 14.
The “Example 3D Printer 10” prints models or parts and their support structures (e.g. 3D part 22) using the filaments of consumable assemblies 12 and part filaments. This is done by layer-based additive manufacturing. Stratasys, Inc., Eden Prairie, Minn., developed fused deposition modelling systems under the trademark “FDM” that are suitable 3D printers 10.Click here to view the patent on Google Patents.