Abstract:
A method of operating an additive manufacturing system feeds solid extrusion material into a heater using a slip clutch coupled to an actuator of a mechanical driver to supply thermoplastic material into a manifold in an extruder head. The method sets a speed of the actuator so the actuator operates at a rotational speed that is slightly greater than the rotational speed of the mechanical mover. This method helps maintain the pressure of the thermoplastic material in the manifold of the extruder head in a predetermined range no matter how many nozzles are opened in the extruder head.
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:
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:
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 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:
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 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.
Abstract:
Provided herein is a document processing system with improved paper path alignment and superior media hold-down capability, which minimizes undesirable electrostatic fields in the print zone. The document processing system includes a first belt module including a first roller and a second roller with a tack belt in surrounding engagement with the first roller and the second roller. The processing system further includes a second belt module, which includes a third roller and a fourth roller with a media transport belt in surrounding engagement with the third roller and the fourth roller. A mounting support for the first belt module is also included herein, the mounting support is designed to allow the first module to self-align relative to the second transport.
Abstract:
Embodiments described herein are directed to a system for reducing velocity transits in a printing system caused by media entering into a transfer nip. The system includes: an imaging drum, a variable speed motor, a transfix roll, a transfix nip, a media transport, a thickness sensor, a skew sensor, a media sensor, a switching means and a controller. Media thickness and/or media skew measurements are used in a feedforward control scheme to increase the imaging drum torque when the media sensor detects a media immediately before it is engaged by the transfer nip.