Apparatus, systems and methods for use in three-dimensional printing are shown and described. Various embodiments of the invention allow for more precise and controlled delivery of heat to achieve interlayer drying; isolation of the working region from the outside for reasons of cleanliness and in connection with the vapors of organic solvents; better control of the temperature of the working region; better accuracy in the flowrates of binder fluid dispensed; matching of delivered flowrates for multiple dispensers; verification of delivered flowrate or drops; provision for easier changeover of the machine from one powder to another; cleanability; and other needs.

Apparatus, systems and methods for use in three-dimensional printing

The invention relates to apparatus (10) and methods for producing three-dimensional objects and auxiliary systems used in conjunction with the aforementioned apparatus and methods. The apparatus and methods involve continuously printing radially about a circular and/or rotating build table (12) using multiple printheads (48). The apparatus and methods also include optionally using multiple build tables. The auxiliary systems relate to build material supply, printhead cleaning, diagnostics, and monitoring operation of the apparatus.

Apparatus and methods for 3D printing

The invention relates to apparatus and methods for producing three-dimensional objects and auxiliary systems used in conjunction with the aforementioned apparatus and methods. The apparatus and methods involve 3D printing and servicing of the equipment used in the associated 3D printer.

Apparatus and methods for servicing 3D printers

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

An image-forming device has a plurality of cylindrical image-carrying members, and an optical scanning unit. The plurality of cylindrical image-carrying members is provided in a main casing for rotating about respective rotational axes. The rotational axes are parallel to one another and juxtaposed in a single direction. The optical scanning unit is provided in the main casing and has a plurality of laser generators, a single rotatable polygon mirror, a plurality of mirrors, and a plurality of lenses. The plurality of laser generators is provided one-to-one relationship to the plurality of image-carrying members to emit respective laser beams. The single rotatable polygon mirror deflects the respective laser beams to scan the respective image-carrying members therewith. The plurality of mirrors is provided one-to-one relationship to the plurality of image-carrying members to guide the respective laser beams along respective optical paths to the respective image-carrying members. The plurality of lenses is provided one-to-one relationship to the plurality of image-carrying members and provided in the respective optical paths and between the respective mirrors and the respective image-carrying members. Distances from the respective mirrors to the respective image-carrying members being equal to one another.

Image-forming device

An isolated amplifier, typically a biomedical amplifier, includes a main amplifier having inputs for receiving signals, a circuit for sensing a common mode voltage received by the inputs from the electrodes and providing a compensation voltage representative of the common mode voltage, and a capacitance to chassis ground for receiving a voltage representative of the compensation voltage. The circuit and the capacitance cause the amplifier power supply voltages to track the common mode voltage. The capacitance permits the feedback loop gain to be increased, thereby reducing common mode voltage errors.

Virtual right leg drive and augmented right leg drive circuits for common mode voltage reduction in ECG and EEG measurements

A pen alignment method for a multi-pen printer is provided, the method including directing a first pen to print a first pattern of a first color, directing a second pen to print a second pattern of a second color in a predetermined relative alignment with the first pattern to form a test block, determining an actual hue of the test block via spectral analysis of the test block using a color sensor, and comparing the actual hue of the test block with an expected hue of the test block to determine whether the first and second pens are misaligned relative to each other, wherein the expected hue of the test block is the hue that would be detected if the first pen and second pen were correctly aligned.

Pen alignment using a color sensor

A compact optical sensing system is used in hardcopy devices for scanning and/or printing images, for instance, using inkjet printing technology in desktop printing or in photographic printers appearing in grocery and variety stores. Several light emitting diodes (“LEDs”) illuminate a sheet of print media, and one or more photodiodes receive light reflected from the sheet. The photodiode generates signals in response to the light received, and the hardcopy device uses these signals to adjust printing parameters for optimal print quality. Using a chip-on-board process, the bare silicon die for each component is wire bonded directly to a printed circuit board assembly, allowing at least four LEDs (blue, green, red and soft-orange) to be grouped closely together in a space smaller than that occupied by a factory-made, single-packaged LED. A calibrating system uses a white target covered for cleanliness by a windowed door which is opened/closed by a printhead carriage.

Calibrating system for a compact optical sensor

A simple, yet accurate way of determining calibration values for correcting the characteristic sinusoidal feed errors of a printer or other recording device (such as a fax machine, plotter, etc.). A sheet of calibration media is employed for facilitating the calculation of the calibration values. The sheet is used in a way that prevents the calibration media errors from affecting the calculation. In particular, the sheet of calibration media is fed twice through the printer, and position data is collected each time. The data is processed in a way that cancels the attendant calibration media errors so that the calculated calibration values precisely correct the characteristic sinusoidal feed errors of that printer.

Calibration of a media advance system

An environmental condition detection system for a hardcopy device, such as an inkjet printing mechanism, includes an environmental condition sensor having an optical property which changes in response to a change in an environmental condition, for instance humidity or temperature. The system also has an optical sensor which detects changes in the optical property and generates a signal for a controller that responds by changing an operating parameter of the hardcopy device. A hard copy device having such a environmental condition detection system is also provided, along with a method of determining an environmental condition within which a hardcopy device is operating.

Algird M. Gudaitis

Papers

Virtual right leg drive and augmented right leg drive circuits for common mode voltage reduction in ECG and EEG measurements

Pen alignment using a color sensor

Calibrating system for a compact optical sensor

Calibration of a media advance system

Environmental factor detection system for inkjet printing