Patent classifications
B29K2105/0067
Method for manufacturing molded article and device for manufacturing molded article
[Problem] The present invention relates to a manufacturing method for obtaining a molded article having an expanded layer in the molded article, wherein an expanding agent and device used to manufacture a resin having expansion properties, and a means for increasing expansion ratio are provided. [Solution] In the present invention, an expanding agent placed in a heating cylinder of a molding machine is configured as a liquid, the volume of the expanding agent is controlled, and the expanding agent is injected into a molten resin in the heating cylinder of the molding machine. The volume of the injected expanding agent can thereby be accurately measured each time. When a low-boiling liquid such as water, an alcohol, or an ether is used as the injected expanding agent, all of the liquid is vaporized by the temperature of the heating cylinder of the molding machine, and no residue thereof is therefore left in the molded article. When sodium bicarbonate water is used as the injected expanding agent, solvent water vaporizes and water vapor also becomes expandable gas, which is less expensive than using sodium bicarbonate as the expanding agent for a master batch using the resin that is to be molded.
Ripple reduction in an additive manufacturing system
An assembly for use in an additive manufacturing system to print a three-dimensional part that includes an extruder comprising a gear and a motor that turns the gear, wherein rotation of the gear regulates a flow of material out of the extruder. A controller, provides a control signal to the motor to control the rate at which the motor turns the at least one gear and incorporates a time-varying signal into the control signal to reduce ripples in the material output by the extruder.
SYSTEMS AND METHODS FOR MANUFACTURING BULKED CONTINUOUS FILAMENT
Systems for manufacturing bulked continuous carpet filament from polymer, where the systems are configured for: (1) melting polymer (e.g., derived from post-consumer PET bottles) to create a first single stream of polymer melt; (2) separating the first single stream of polymer melt into multiple streams of polymer melt; (3) exposing the multiple streams of polymer melt to a pressure of between about 0 millibars and about 5 millibars; (4) allowing the multiple streams of polymer melt to fall into a receiving section of a melt processing unit; (5) recombining the multiple streams of polymer melt into a second single stream of polymer melt; and (6) providing the second single stream of polymer melt to one or more spinning machines that are configured to form the second single stream of polymer melt into bulked continuous carpet filament.
Insert to reduce weld line appearance defect in injection molding
A method of forming a part includes locating an insert at an angle within a mold cavity, sending a quantity of molten resin through the mold cavity to form a first melt front, and sending another quantity of molten resin through the mold cavity to form a second melt front such that the first melt front meets the second melt front at a weld line and each front flows along opposite sides of the insert. The mold cavity can define opposed internal surfaces and the insert can be disposed at an angle between the internal surfaces at the weld line. Also, one end of the insert can be fixedly located to one of the opposed internal surfaces and another end of the insert can float within the mold cavity.
Methods for manufacturing bulked continuous filament from recycled PET
A method of manufacturing bulked continuous carpet filament that includes providing a polymer melt and separating the polymer melt from the extruder into at least eight streams. The multiple streams are exposed to a chamber pressure within a chamber that is below approximately 25 millibars, or another predetermined pressure. The streams are recombined into a single polymer stream. Polymer from the polymer stream is then formed into bulked continuous carpet filament.
SYSTEMS AND METHODS FOR MANUFACTURING BULKED CONTINUOUS FILAMENT FROM COLORED RECYLED PET
A system comprising: (1) a grinding unit configured to receive and grind recycled PET bottles into a group of polymer flakes comprising up to about ten percent colored polymer flakes and balance substantially clear polymer flakes; (2) a washing unit configured to wash the group of polymer flakes; and (3) an extruder configured to extrude material in a plurality of different extrusion streams. The extruder may be further configured to: (1) receive a concentrate-polymer mixture comprising a mixture of the polymer flakes and a color concentrate; (2) melt the concentrate-polymer mixture to produce a polymer melt; (3) reduce a pressure within the extruder; and (4) pass the polymer melt through the extruder so that the polymer melt is divided into the plurality of extrusion streams. The system may then filter the polymer melt through at least one filter and form the polymer melt into bulked continuous carpet filament.
Ribbon liquefier and method of use in extrusion-based digital manufacturing systems
A ribbon liquefier comprising an outer liquefier portion configured to receive thermal energy from a heat transfer component, and a channel at least partially defined by the outer liquefier portion, where the channel has dimensions that are configured to receive the ribbon filament, and where the ribbon liquefier is configured to melt the ribbon filament received in the channel to at least an extrudable state with the received thermal energy to provide a melt flow. The dimensions of the channel are further configured to conform the melt flow from an axially-asymmetric flow to a substantially axially-symmetric flow in an extrusion tip connected to the ribbon liquefier.
Filament swapping in three-dimensional printing
An extruder is fitted with a connector for coupling and decoupling with a filament feed source, such as a filament tube. When connected, the extruder and filament tube are aligned to define a feed path for a filament. A tool rack includes a plurality of filament tubes secured within respective openings. The tool rack may facilitate coupling and decoupling operations between the extruder and filament sources. For example, the tool rack may define an insertion path that engages a filament tube during insertion, and that secures the filament tube against an excursion from the insertion path. The extruder may disengage the coupling by initiating a motion along the insertion path and then moving off of the insertion path to decouple the filament tube and the extruder. In this manner, filaments may be swapped through engaging and disengaging the extruder with different filament tubes on the tool rack.
SYSTEMS AND METHODS FOR MANUFACTURING BULKED CONTINUOUS FILAMENT FROM COLORED RECYCLED PET
Methods of manufacturing bulked continuous carpet filament which, in various embodiments, comprise: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) adding one or more color concentrates to the flakes; (E) passing the group of flakes through an MRS extruder (400) while maintaining the pressure within the MRS portion (420) of the MRS extruder (400) below about 25 millibars; (F) passing the resulting polymer melt through at least one filter (450) having a micron rating of less than about 50 microns; and (G) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.
Systems and methods for manufacturing bulked continuous filament
A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) passing the group of flakes through an MRS extruder while maintaining the pressure within the MRS portion of the MRS extruder below about 1.5 millibars; (E) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (F) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.