Hewlett-Packard Development Company, L.p.

Hewlett-Packard Company

Other

Xaar Technology Limited

Andrew L Van Brocklin

Peter James Fricke

Daryl E Anderson

Eric T Martin

Adam L Ghozeil

Andrew Koll

David Maxfield

James F Bausch

Greg J Lipinski

Scott A Linn

D Mitchel Hanks

Alexander N Govyadinov

Kenneth James Eldredge

Neel Banerjee

Paul A Liebert

Makarand P Gore

Michael A Pate

Mark Hunter

Chadwick W Stryker

William E Dorogy

James E Ellenson

David Michael Kwasny

Kuohua Wu

Neal W Meyer

Antonio Cruz-Uribe

Sarah Morris Brandenberger

John R Sterner

Steven C Johnson

Cari L Dorsh

Stephan R Clark

Chris Bakker

Darwin Mitchel Hanks

Frederick A Perner

James Michael Gardner

Warren Bruce Jackson

Sterling Chaffins

Vladek P Kasperchik

Kenneth Kay Smith

Lung T Tran

Gregory J May

Jayprakash C Bhatt

Charles Robert Weirauch

Lawrence Nathaniel Taugher

Dustin W Blair

Jefferson Patrick Ward

Glen Allen Oross

William James Allen

David A Champion

Janice H Nickel

Andrew Arthur Hunter

James R Cole

John Christopher Rudin

Dennis M Lazaroff

Stephen Mark Jeapes

S Jonathan Wang

Jeffrey M Valley

Paul H McClelland

Randy Hoffman

Kurt M Ulmer

James William Stasiak

Dennis Raymond Esterberg

Jacques H Helot

Donald W Schulte

Manish Giri

Terry E McMahon

James P Shields

Greg Scott Long

Tony S Cruz-Uribe

Eric Lee Nikkel

P Guy Howard

Chantelle Domingue

Ronald A Hellekson

Robert N K Browning

Kevin P Dekam

John M Koegler, Iii

Marshall Field

Laurence Meade Hubby, Jr

Darrel R Bloomquist

Melinda M Valencia

John Liebeskind

Paul Boerger

Timothy F Myers

John A Devos

James Robert Eaton

David Punsalan

John M Da Cunha

David Pidwerbecki

Kevin Lawrence Colburn

Peter Guy Howard

Judy Bloomquist, Legal Representative

David Pettigrew

Douglas Pederson

Kenneth Michael Kramer

William C Wickes

Michael J Day

Matthew Jason Janssen

Nicholas McGuinness

Susan E Bailey

John Arthur deVos

In an example implementation, a sintering system includes a support structure in a sintering furnace to support a token green object during a sintering process. The system includes wires installed into the furnace and through the support structure to contact the object. An impedance meter is operatively coupled to the wires to determine electrical impedance of the object during the sintering process.

Electrical measurement of a green object during sintering

In an example implementation, a sintering system includes optical fiber installed into a sintering furnace. A support structure inside the furnace is to support a token green object in a predetermined position and to hold a distal end of the fiber adjacent to the predetermined position. A light source is operably engaged at a proximal end of the fiber to transmit light through the fiber into the furnace. A light detector is operably engaged at the proximal end of the fiber to receive reflected light through the fiber that scatters off a surface of the token green object.

Transmitting and detecting light with optical fiber during sintering

According to one example there is provided a non-transitory computer readable storage medium comprising instructions that, when executed by a processor, cause the processor to: obtain an object model; analyse the object model; obtain characteristics of an interface agent; generate a modified object model comprising a support structure and an interface between the support structure and the object, the interface being such that after generation of a 3D printed green part and after sintering thereof, the support structure may be released with a predetermined force; and controlling a 3D printer to generate a 3D printed green part based on the modified object model.

Support structures and interfaces

In an example of a method for three-dimensional (3D) printing, a polymeric or polymeric composite build material is applied. A dielectric agent is selectively applied on at least a portion of the polymeric or polymeric composite build material. The dielectric agent includes a dielectric material having an effective relative permittivity (&#x3b5;) value ranging from 1.1 to about 10,000. A fusing agent is selectively applied on the at least the portion of the polymeric or polymeric composite build material, and the polymeric or polymeric composite build material is exposed to radiation to fuse the at least the portion of the polymeric or polymeric composite build material to form a region of a layer of a 3D part. The region exhibits a dielectric property, a piezoelectric property, or a combination thereof.

Three-dimensional printing

Measuring an inkjet nozzle may include taking at least one impedance measurement after the firing command is sent to detect the presence of a drive bubble and taking another impedance measurement to detect a collapse of the drive bubble.

Detecting a drive bubble formation and collapse

A print head assembly (PHA) includes a microelectromechanical systems (MEMS) die mounted to a substrate with an application specific integrated circuit (ASIC). The die includes an opening defined in the die, a plurality of nozzles adjacent to the opening in fluid communication with the opening, and a pad to receive electrical control signals. The ASIC includes a communication link and a plurality of transmission lines that transmit electrical signals to the MEMS die.

Apparatus with microelectromechanical die and application specific integrated circuit

In some examples, a controller receives impedance sensor values from an impedance sensor in a printhead, determines whether the impedance sensor values correlate to a production of an effective drive bubble for the printhead, and issues a command to modify a firing parameter for a fluid ejector of the printhead based on the impedance sensor values.

Modifying firing parameters for printheads

A printhead circuit for providing pulses for driving two or more actuating elements, the circuit comprising a cold switch drive circuit, for driving an actuating element for a first phase of a first pulse, the cold switch drive circuit having a cold drive switch for selectively coupling a drive waveform to the actuating element during the first phase according to a print signal; and a hot switch drive circuit, for driving the actuating element for a second phase of the first pulse, wherein the hot switch drive circuit is configured to drive the actuating element during the second phase according to an actuating element compensation indication signal.

Printhead circuit

An apparatus includes an amplifier to drive a piezo print nozzle in response to a bias current. A bias adjuster includes a plurality of side legs and a plurality of current mirrors. The bias adjuster varies the bias current in the amplifier based on a variable slew rate associated with an input signal of a print command. The bias adjuster is to selectively mitigate power loss and increase slew rate performance of the amplifier.

Bias current control for print nozzle amplifier

In some examples, a printing system comprises a plurality of microelectromechanical systems (MEMS) dies comprising printing fluid jets, a printhead assembly (PHA) application specific integrated circuit (ASIC), and a substrate comprising the plurality of MEMS dies and the PHA ASIC. The PHA ASIC is to process image data into a plurality of data signals that define a firing pattern, and transmit the data signals through transmission lines on the substrate to the plurality of MEMS dies. The printing fluid jets of the plurality of MEMS dies are to fire in response to the data signals.

Printing system comprising a microelectromechanical die and an application specific integrated circuit

In some examples, a method of regulating a temperature of a printhead includes charging, in a first state of a temperature regulator, an analog memory to a reference voltage that corresponds to a predetermined temperature of the printhead. The temperature regulator monitors, during a second state, the temperature of the printhead, the monitoring including measuring a thermal voltage representing an actual temperature of at least a first local area of a plurality of local areas of the printhead, and comparing, with a comparator, the reference voltage to the thermal voltage to obtain a comparison result for at least the first local area. Based on the comparison result, a series of warming pulses from a warming pulse circuit to at least the first local area is selectively enabled.

Method and apparatus to regulate temperature of printheads

An inkjet printhead device, fluid ejection device and method thereof are disclosed. The fluid ejection device includes a fluid supply chamber to store fluid, an ejection chamber including a nozzle and a corresponding ejection member to selectively eject the fluid through the nozzle, and a channel to establish fluid communication between the fluid supply chamber and the ejection chamber. The fluid ejection device also includes a pressure sensor unit having a sensor plate to output a voltage value corresponding to a cross-sectional area of an amount of fluid in the at least ejection chamber.

Inkjet printhead device, fluid ejection device, and method thereof

In an implementation, a printhead includes a nozzle and a fluid channel. A sensor plate is located within the fluid channel. An impedance measurement circuit is coupled to the sensor plate to measure impedance of fluid within the channel during a fluid movement event that moves fluid past the sensor plate.

Printheads with sensor plate impedance measurement

In some examples, a drive signal generator for a fluid ejection element of a piezoelectric printhead, includes a core amplifier to amplify an input waveform to provide an amplified waveform, and a plurality of rail power circuits, each coupled to a different power input of the core amplifier. Each rail power circuit of the plurality of rail power circuits includes a comparator to compare an instantaneous voltage of the amplified waveform to a subset of a plurality of voltage sources, and a switch to, based on the comparing by the comparator, couple to a respective power input of the core amplifier a voltage source in the subset of the plurality of voltage sources that is closest to the instantaneous voltage and sufficient to generate the amplified waveform.

Printhead waveform voltage amplifier

Growing community of inventors

Corvallis, OR, United States of America

Andrew L Van Brocklin