Xerox Corporation

Tektronix, Inc.

Palo Alto Research Center Inc.

Additive Technologies LLC

Tektronics, Inc.

David Lyell Knierim

Brent Rodney Jones

Ernest I Esplin

Trevor James Snyder

Edward Francis Burress

Barry Daniel Reeves

Richard Guy Chambers

Jasper Kent Wong

David Douglas Martenson

Michael E Jones

James D Buehler

Donald R Titterington

Douglas Dean Darling

Ivan Andrew McCracken

Daniel G Knierim

Bo Wu

Jule W Thomas, Jr

Terrance Lee Stephens

David Paul Platt

John Charles Dalrymple

Chad Johan Slenes

Isaac S Frazier

James Michael Bonicatto

Jonathan Robert Brick

Randall Ray Bridgeman

James Dudley Padgett

Edward F Burke

James Bruce Campbell

Steven Ross Slotto

Guenther W Wimmer

Chu-Heng Liu

Paul J McConville

Jeffrey J Folkins

John Richard Andrews

Peter Johan Nystrom

Lloyd A Williams

Andrew V Hill

Joannes N M deJong

Steven E Ready

Michael Alan Fairchild

Chad David Freitag

Scott J Korn

Stephen Michael Kroon

Gustavo J Yusem

James B Jensen

Bruce K Baur

Joel Chan

Nasser Alavizadeh

Michael Kenneth Oehl

Michael Edward Norkitis

Steven V Korol

Gary L Brown

Christian Carl Gadke

Jennifer Misae Miyamoto

Aaron L Boyce

Harvey J Rosener

Lee M Oien

Nathaniel Morrison

Amy R Bartlett

Elliott A Eklund

Mark Raymond Parker

William Bruce Weaver

John Milton Brookfield

Brent Edward Fleming

Walter Sean Harris

Reid Wayne Gunnell

Brian Edward Williams

David Alan Tence

Mirza Sabanovic

Douglas J Doornink

Russell J Watt

Christine M Greiser

Christian Amoah-Kusi

Curtis Douglass Keller

Gautam Dhar

Blake Terry Weimer

Tygh James Newton

Bradford Stewart

David Scott Allaway

Mark H Cowan

Daniel Mark Platt

A J Rogers

Richard S Meissner

Andrew W Hill

Takahiro Peter Terayama

Monica Louise Maestas

Kenneth Eugene Strohmeyer, Jr

Tesfalem Zewdneh

David D Matenson

Megan Schaffer

Lee D Hills

David Allaway

Christian C Gadke

David D Martenson

Joannes N M Dejong

James B Campbell

A current measurement device includes a shunt having sense leads, the shunt configured to be located in a current path for a current to be measured, and a Rogowski coil at least partially wrapped around the shunt, the current measuring device configured to combine signals from the shunt and the Rogowski coil. A current measurement device includes a shunt having sense leads configured to be located in a current path for a current to be measured, a Rogowski coil in series with the sense leads and at least partially wrapped around the shunt, a compensating pole connected to the Rogowski coil, and an isolation barrier connected to the compensating pole.

Current monitor combining a shunt resistor with a Rogowski coil

A printer includes print heads configured to eject ink drops onto print media to form images, a controller connected to the print heads to control the print heads to eject ink drops to form the images including one or more test images, one or more actuators to cause the print media to pass the print heads, and at least one camera to capture one or more optical images of the print media after the print media passes the print heads, the controller to detect the test images in the optical images and to measure print characteristics in the test image. A method of measuring ink jet print head alignment includes capturing one or more optical images of media containing printed images, detecting optical images that contain specific printed test images, and measuring print characteristics based upon image data derived from the specific printed test images.

Print head angle and stitch alignment during full speed printer operation

An implementation of the present teachings includes a resistor structure for measuring a level of a print material such as a liquid metal print material within a reservoir of a printer such as a magnetohydrodynamic printer. The resistor structure includes a first electrode and a second electrode that are physically and electrically separated from each other. When positioned within the reservoir, the liquid metal physically contacts the first electrode and the second electrode. An electrical resistance between the first and second electrodes changes depending on the level of the print material within the reservoir. As the level of the print material decreases, the electrical resistance between the first electrode and the second electrode increases. The electrical resistance can be measured and used to determine a level of the print material within the reservoir.

Resistive liquid metal level sensing in a magnetohydrodynamic (MHD) jetting system

A system to direct print onto print substrates has a print head, at least one optical image sensor arranged adjacent a print substrate, wherein the print substrate will move in a process direction past the print head, at least one telecentric lens arranged between the print substrate and the at least one optical image sensor, and control circuitry electrically connected to the optical at least one image sensor and the print head, the control circuitry to generate dot clocks to cause the print head to print onto the substrate based upon data from the at least one optical image sensor identifying a position of the print substrate.

Print substrate optical motion sensing and dot clock generation

A print head, has a standardized computer interface to allow the print head to connect directly to a standard computer, an array of jets to deposit ink on a substrate in accordance with image data from the standard computer, a processing element to receive image data through the standardized computer interface, a buffer to store the image data received through the standardized computer interface and to transmit the image data to the array of jets when triggered by a dot clock, the buffer under control of the processing element and having a flexible depth of storage, and a driver to trigger individual ones of the array of jets in accordance with the image data.

Ink jet print head with standard computer interface

A method for measuring an impedance of each of a plurality of piezoelectric actuators of a print head, each piezoelectric actuator connected to electronic selection circuitry of the print head that drives the piezoelectric actuators during a print operation. The method includes generating a waveform to drive a drive rail of the print head, the drive rail connected to the electronic selection circuitry of the print head and measuring an impedance of each of the plurality of piezoelectrical actuators of the print head through the electronic selection circuitry.

Impedance measurement of individual actuators of a piezoelectric print head

An energy recovery circuit in a print head includes at least one waveform rail, an array of piezoelectric actuators selectively electrically connectable to the waveform rail, the piezoelectric actuators creating a capacitive load, at least one pseudo jet capacitive load, selectively coupled to the waveform rail, depending upon how many piezoelectric actuators are connected to the waveform rail, and a first inductor coupled to the waveform rail, wherein the first inductor forms a resonant circuit with a waveform rail capacitance and returns energy to a power supply. A method of recovering energy in a print head includes providing a waveform to an array of piezoelectric actuators that are selectively electrically connectable to a waveform rail, selectively coupling at least one pseudo-jet load to the waveform rail, depending upon how many piezoelectric actuators are connected to the waveform rail, and using an inductor to form a resonant circuit with a waveform rail capacitance and to return energy to a power supply.

Piezoelectric print head drive with energy recovery

A print head, including a plurality of piezoelectric actuators, a pseudo-actuator, a drive rail, electronic selection circuitry connected to each of the plurality of piezoelectric actuators, the pseudo-actuator, and the drive rail, the electronic selection circuitry configured to select at least one of the piezoelectric actuators or the pseudo-actuator to connect to the drive rail, and a controller coupled to the drive rail, the controller configured to generate a waveform to drive the drive rail and measure a signal on the drive rail connected to a piezoelectric actuator, a pseudo-actuator, or without any connected piezoelectric actuators or the pseudo-actuator, and using the resulting measurements to calculate an impedance of a piezoelectric actuator.

Print head with integrated jet impedance measurement

A printing system has a print head shuttle containing a print head mounted on a print guide rail, a support shuttle containing support electronics for the print head mounted on a support guide rail adjacent and parallel to the print guide rail, and at least one electronic signal-carrying cable connected between the support electronics and the print head.

Print head shuttling motion with improved precision

A method, includes receiving native image data at a processor for a printing system having a jet stack including a nozzle plate with an array of jets, formatting the native image data by pixels for each jet within the array of jets to produce ordered image data, scanning the ordered image data to determine timing and frequency of any pre-fire sequences needed for each jet, replacing a portion of the ordered image data for jets that need pre-fire sequences with a predetermined trigger sequence followed by a number and pattern of pre-fire pulses to produce modified image data, and transmit the modified image data.

Ink jet pre-fire waveform control

An inkjet printing system, including an inlet in a print head to receive ink from an ink supply, a plurality of nozzles to eject ink in the print head, an ink pressure sensor disposed in an ink path, the ink pressure sensor configured to determine an ink pressure of the ink in the print head and output a signal indicating the ink pressure, and a controller in the print head configured to receive and process the signal indicating the ink pressure from the ink pressure sensor. The inkjet printing system may also include a memory to store an ink pressure and time profile. The controller may also output a signal to stop ejecting ink from the plurality of nozzles when the ink pressure is either below a negative threshold or above a positive threshold.

Print head having ink pressure sensor

Print head jet stack heating and temperature measurement systems and methods are disclosed that both heat the jet stack and determine a temperature of the jet stack. The heating and temperature determination are performed by a flex circuit that includes multiple layers. One of the layers heats the jet stack and another one of the layers provides data that determines the temperature of the jet stack. The heating layer and the temperature sensing layer are separated by an insulative material in the flex circuit. The temperature of the jet stack can be sent to a print head controller that then determines whether to increase or decrease the temperature of the jet stack.

Systems and methods for heating and measuring temperature of print head jet stacks

A method of bonding two components includes plating a first of the components with a first silver layer, a tin layer, and a second silver layer, plating a second of the components with silver, inserting the first and second components into a pre-heated press, and applying pressure to the components causing the components to bond. A stack of layers has a first component layer, a first silver layer, a tin layer, a second silver layer, a second component silver layer, and a second component layer.

Tin-silver diffusion soldering for thin joints without flux

A method of filling a print head includes drawing a vapor into an empty print head to displace any air in the print head and filling the print head with ink. A method of filling a print head includes connecting a print head to a vacuum pump using a first valve, to a liquid supply using a second valve, and to an ink supply using a third valve, opening the first and second valves, applying vacuum to the print head and liquid supply using the vacuum pump, causing the liquid to generate a vapor that moves into the print head, closing the first valve and the second valve, and opening the third valve to move ink into the print head.

Water-vapor assist for filling aqueous print heads

A fluid sensor has a first electrode, a second electrode, a housing containing the first and second electrodes, such that the electrodes extend from the housing, exposed metal between the first and second electrodes, and a drive signal electrically connected to the second electrode, such that when fluid is present in the reservoir, either the first electrode senses the presence of the fluid, or the drive signal senses presence of the fluid. A fluid sensor has a first electrode, a second electrode, a housing containing the first and second electrodes, a drive signal electrically connected to the second electrode, and sensing circuitry to measure a current from the second electrode to indicate a fluid level.

Fluid level sensor with combined capacitance and conductance

Growing community of inventors

Wilsonville, OR, United States of America

David Lyell Knierim