Abstract: An additive manufacturing system includes a slip clutch coupled to an actuator of a mechanical driver that feeds solid extrusion material into a heater for supplying thermoplastic material to a manifold in an extruder head. A speed of the actuator can be set to enable the actuator to operate at a rotational speed that is slightly greater than the rotational speed of the mechanical mover. This configuration enables the pressure of the thermoplastic material in the manifold of the extruder head to be in a predetermined range no matter how many nozzles are opened in the extruder head.

Abstract: A printer is configured with at least two printheads that are separated from one another in a cross-process direction by an integral multiple of printhead widths. This configuration enables parallel swaths of material to be ejected and then movement of the printheads in the cross-process direction by a distance corresponding to one or more integral numbers of the printhead width enables the area between the swaths to be completed and the area outside of the original swaths printed.

Abstract: A three-dimensional object printing system improves the interlayer adhesion of an object. The printing system includes a platform on which a three-dimensional object is built. A material applicator in the printing system expels material to form layers of the object on the platform. The material applicator also includes a heater configured to heat the layer of the object ahead of the material applicator when the material applicator moves in a first direction and a second direction, both directions being parallel to the platform.

Abstract: An additive manufacturing system operates at least one ejector and an extruder to form three-dimensional objects with photopolymer material and thermoplastic material. The system operates to deposit the two materials in a layer-by-layer manner. The photopolymer material provides high resolution finishes on the objects and the thermoplastic material enables strong and stable formation of internal portions of the objects.

Abstract: A pin actuated printhead includes an orifice through which a material is ejected, a chamber to hold the material to be ejected, a channel connecting the chamber to the orifice, and an actuated pin, to enter the orifice and to eject the material from the orifice. The printhead is configured to eject a material with a viscosity of 10,000 cP or more at an elevated temperature.

Abstract: A three-dimensional object printer includes a multi-nozzle extruder, at least one extrusion material supply, and a dispenser that provides extrusion material from the extrusion material supply to each of a plurality of channels, each channel supplying extrusion material to at least one nozzle in the multi nozzle extruder. The dispenser includes an inlet to receive extrusion material from at least one extrusion material supply, an outlet configured to direct the extrusion material to a channel in the plurality of channels, and an actuator configured to move the outlet into alignment with each channel in the plurality of channels.

Abstract: A 3D printer including a pin actuated printhead having an orifice through which a material is ejected, a material chamber to hold the material to be ejected, a channel connecting the material chamber to the orifice, a pin chamber, and an actuated pin within the pin chamber, wherein the actuated pin extends through the pin chamber to eject the material from the orifice. The printhead is configured to eject a material with a viscosity of 10,000 cP or more at an elevated temperature. The 3D printer further includes a material delivery system having a filament driver and a filament heater.

Abstract: A multi-nozzle extrusion printhead includes a chamber with an inlet to receive an extrusion material and a plurality of outlets fluidly coupled to the chamber. The printhead also includes a plurality of valves that control flow of extrusion material through the fluid outlets to nozzles in the printhead. Each valve includes a member and an electromechanical actuator configured to move the member to a first position to block a flow of the extrusion material through one of the fluid outlets and nozzles and to a second position to enable the flow of the extrusion material through the fluid outlet and nozzles.

Abstract: A method of operating a multi-nozzle extrusion printhead includes operating with a controller a first actuator to produce relative movement between the printhead and an image receiving surface along a predetermined path for one layer of a three-dimensional printed object. The method further includes first printing an outline of a given layer and then printing the interior of the given layer using a plurality of extrusion nozzles. The method further optionally includes extruding material through a portion of the plurality of nozzles and turning on or off individual nozzles to ensure the swaths printed in the interior conform to the profile of the outline.

Abstract: A three-dimensional object printer uses stereolithography to form a structure and then embed one or more objects in the structure. The printer includes a controller that operates a source of ultraviolet (UV) radiation to cure a portion of a liquid photopolymer at an interface between the liquid photopolymer and the external surface of an embedded object with reference to a meniscus formed between the liquid photopolymer and the external surface of an embedded object. The incorporation of the embedded object speeds formation of the final object and increases the durability of the final object.

Abstract: A three-dimensional object printer includes a controller that operates at least one ejector to place a layer of photopolymer material on a substrate. The controller is configured to cure the ejected photopolymer layer partially and position fiber on the cured layer before continuing to eject photopolymer material onto the fibers. The fibers can be loose or organized into a mesh. The pieces of mesh position on a cured layer can be pre-cut or a cutting device can be operated to cut pieces of mesh having a shape that corresponds to the shape of the layer of photopolymer material. The fibers reinforce the layers of photopolymer material and add strength and durability to the overall part being formed with the photopolymer material.

Abstract: A pin actuated printhead includes an orifice through which a material is ejected, a chamber to hold the material to be ejected, a channel connecting the chamber to the orifice, and an actuated pin, to enter the orifice and to eject the material from the orifice. The printhead is configured to eject a material with a viscosity of 10,000 cP or more at an elevated temperature.

Abstract: What is disclosed is a method for monitoring a subject for cardiac arrhythmia such as atrial fibrillation using an apparatus that can be comfortably worn by the subject around an area of exposed skin where a photoplethysmographic (PPG) signal can be registered. In one embodiment, the apparatus is a reflective or transmissive wrist-worn device with emitter/detector pairs fixed to an inner side of a band with at least one illuminator emitting source light at a specified wavelength band. The illuminator is paired to a respective photodetector comprising one or more sensors that are sensitive to a wavelength band of its paired illuminator. The photodetector measures intensity of sensed light emitted by a respective illuminator. The signal obtained by the sensors comprises a continuous PPG signal. The continuous PPG signal analyzed for peak-to-peak pulse points from which the existence of cardiac arrhythmia such as atrial fibrillation event can be determined.

Abstract: A printhead including a plurality of actuators, wherein each actuator of the plurality of actuators includes a plurality of drive electrodes, a plurality of diaphragms, and a single nozzle. Each drive electrode is uniquely paired with one of the diaphragms. In an embodiment, the printhead may be configured so that all drive electrodes for a single actuator always activate simultaneously to eject ink from the single nozzle. In another embodiment, the printhead may be configured so that each drive electrode of the plurality of drive electrodes for a single actuator are individually addressable and may be fired independently of the other drive electrodes of the single actuator.

Abstract: A printing device includes an array of printheads, an actuator, and a controller. The actuator is configured to move the printheads between: a first distance from a surface on which an ink image is to be formed that enables the printheads to eject ink and form a portion of the ink image on the surface; and a second distance from the surface that is greater than the first distance. Both the first and second distances are within a print zone of the printing device. The controller is configured to identify at least one printhead that is not used for a portion of a print job, and is further configured to operate the actuator to move the identified printhead to the second distance from the surface.

Abstract: According to aspects illustrated herein, a system, a printmaking device, and a method for pre-curling and registering media are provided herein. The system includes a media curler system and a deskew mechanism. The media curler system pre-curls at least one of lead edge and a trail edge of a sheet before delivery to a media hold-down transport. The deskew mechanism is coupled to the media curler system for pivoting the media curler system about a pivot axis to deskew the sheet. The pivot axis extends perpendicular to the media transport path. In operation, as the lead edge enters the pre-curling and registration system, the media curler system pre-curls the sheet towards the media hold-down transport. As the sheet is being pre-curled, the deskew mechanism pivots the media curler system about the pivot axis to correct any skew errors in the sheet.

Abstract: A printhead including a plurality of actuators, wherein each actuator of the plurality of actuators includes a plurality of drive electrodes, a plurality of diaphragms, and a single nozzle. Each drive electrode is uniquely paired with one of the diaphragms. In an embodiment, the printhead may be configured so that all drive electrodes for a single actuator always activate simultaneously to eject ink from the single nozzle. In another embodiment, the printhead may be configured so that each drive electrode of the plurality of drive electrodes for a single actuator are individually addressable and may be fired independently of the other drive electrodes of the single actuator.

Abstract: A printhead including a venting system and an actuator array, wherein each actuator may include an actuator air chamber. The venting system includes an air path that vents each actuator air chamber to the atmosphere. The printhead further includes a dryer configured to remove moisture from air within the air path. The dryer may include a passive desiccant, an active resistive heater, or both.

Abstract: A printhead including a venting system and an actuator array, wherein each actuator may include an actuator air chamber. The venting system includes an air path that vents each actuator air chamber to the atmosphere. The printhead further includes a dryer configured to remove moisture from air within the air path. The dryer may include a passive desiccant, an active resistive heater, or both.

Abstract: Embodiments described herein are directed to a reflex printing system with improved image quality. A media transport moves a media substrate or an intermediate belt along a media path in a process direction past the two or more print heads, which deposit inks onto the media substrate or the intermediate belt. A velocity measuring device directly measures and transmits the speed of the surface of belt or media that is to receive the image to a controller, which sends print commands to the two or more print heads to control the frequency of the printing. The inks deposited on the media substrate or intermediate belt have a color registration of from 10 to 20 microns.