Abstract: An apparatus, method, and a fluid ejection system for detecting electrical shorts in piezoelectric printheads are described. An apparatus includes a piezoelectric actuator, a transistor whose drain is connected to the piezoelectric actuator, a diode that is connected to a source and the drain of the transistor, a detection circuit configured to detect whether a voltage at the drain of the transistor is above a predefined voltage, and a disabling circuit configured to turning off the transistor in response to detecting that voltage at the drain of the transistor is above the predefined voltage.

Abstract: In general, in one aspect, the invention features a method for driving a droplet ejection device having an actuator, including applying a multipulse waveform that includes two or more drive pulses to the actuator to cause the droplet ejection device to eject a single droplet of a fluid, wherein a frequency of the drive pulses is greater than a natural frequency, fj, of the droplet ejection device.

Abstract: Among other things, the disclosure features a system for use in fluid jetting. The system comprises a first print module comprising a first row of nozzles, a second print module comprising a second row of nozzles, and a controller to receive a first data packet from a remote device at a first moment and a second data packet from the remote device at a second moment after the first moment. Upon receipt of the first data packet, the controller is configured to cause at least some nozzles in the first row, at a third moment, to eject fluid droplets onto a line on a substrate. Upon receipt of the second data packet, the controller is configured to cause at least some nozzles in the second row, at a fourth moment separated from the third moment by a time delay, to eject fluid droplets onto the line on the substrate.

Abstract: Please replace the abstract at page 29 with the following amended abstract: Among other things, the disclosure features a system for use in fluid jetting. The system comprises a first print module comprising a first row of nozzles, a second print module comprising a second row of nozzles, and a controller to receive a first data packet from a remote device at a first moment and a second data packet from the remote device at a second moment after the first moment. Upon receipt of the first data packet, the controller is configured to cause at least some nozzles in the first row, at a third moment, to eject fluid droplets onto a line on a substrate. Upon receipt of the second data packet, the controller is configured to cause at least some nozzles in the second row, at a fourth moment separated from the third moment by a time delay, to eject fluid droplets onto the line on the substrate.

Abstract: An electronic architecture for an imaging data path allows for printing on objects that are unevenly spaced. The architecture uses a rolling image buffer into which images are copied. A hardware trigger can optionally be used in conjunction with the rolling image buffer to prevent any printing mismatches that could otherwise be caused by a software delay. The trigger relates the physical location of the object to a virtual location in the image buffer.

Abstract: Systems and techniques for printing on a workpiece. In one implementation, a data pump is used to create a packet of image data for a print head assembly. The data pump includes multiple state machines to receive image data from an image buffer on a computer, and a serializer to gather image data from each of the state machines. Each of the state machines is configured to send image data to the serializer at a different instance in time. The serializer is configured to arrange the gathered image data according to when the serializer received the image data from each of the state machines. The data pump also includes an optical fiber communication interface to connect with a communication channel.

Abstract: Fluid ejection apparatuses and processes for making the same are disclosed. An apparatus for ejecting fluid droplets includes a substrate having a plurality of flow paths formed therein, each flow path including a respective pumping chamber and a respective nozzle, and the respective nozzle being configured to eject fluid droplets through a first surface of the substrate in response to actuation of the respective pumping chamber; and an actuation assembly including a drive electrode layer over a second surface of the substrate opposite to the first surface, a piezoelectric layer over the drive electrode layer, and a reference electrode layer over the piezoelectric layer, the drive electrode layer being patterned to define an individually controllable drive electrode over each of two or more pumping chambers in the substrate, and the reference electrode layer including a continuous reference electrode spanning the two or more pumping chambers in the substrate.

Abstract: A device for depositing drops includes a head configured to eject drops on a region of a substrate; a stage configured to hold the substrate while the head ejects drops on the region of the substrate; a first transporting device configured to transport the substrate in a transporting direction onto the stage; and a second transporting device configured to transport the substrate in the transporting direction off the stage. The stage and at least one of the first transporting device or the second transporting device are movable together in the transporting direction.

Abstract: Ink jet printheads and printhead components having a body that include a flow path, a piezoelectric actuator having a piezoelectric layer fixed to the body and an impedance feature in the flow path are described. The impedance feature includes a plurality of posts arranged in a first row, at least one post in the first row of posts having a downstream surface that is concave.

Abstract: An electronic architecture for an imaging data path allows for printing on objects that are unevenly spaced. The architecture uses a rolling image buffer into which images are copied. A hardware trigger can optionally be used in conjunction with the rolling image buffer to prevent any printing mismatches that could otherwise be caused by a software delay. The trigger relates the physical location of the object to a virtual location in the image buffer.

Abstract: Systems and techniques for printing. In one implementation, a method includes printing, at substantially the same time, a first image on a first workpiece and a second image on a second workpiece.

Abstract: Techniques, systems, and computer program products for transmitting data between a computer system and an external printing device. A technique may include generating a data packet in accordance with a communications protocol such that generating the data packet includes encoding the data packet according to a second layer of the protocol in a frame format according to a third layer of the protocol, transmitting the data packet from the computer system to the external printing device according to the first layer of the protocol; and decoding the data packet in accordance with the second layer of the protocol. The protocol can be defined to include three layers. In that protocol, a first layer may define transmission line, transmitters, and receivers for transmission, the second layer may define encoding and decoding, and the third layer may define a frame format of the data packet.

Abstract: A printer is described that has a configurable memory to which waveform definitions are uploaded just prior to a printing process. The printer manufacturer can program a printer controller with waveforms that have been created by the printer manufacturer, instead of waveforms pre-programmed by the printhead manufacturer.

Abstract: A method for causing ink to be ejected from an ink chamber of an ink jet printer includes causing a first bolus of ink to be extruded from the ink chamber; and following lapse of a selected interval, causing a second bolus of ink to be extruded from the ink chamber. The interval is selected to be greater than the reciprocal of the fundamental resonant frequency of the chamber, and such that the first bolus remains in contact with ink in the ink chamber at the time that the second bolus is extruded.

Abstract: Techniques, systems, and computer program products for transmitting data between a computer system and an external printing device. A technique may include generating a data packet in accordance with a communications protocol such that generating the data packet includes encoding the data packet according to a second layer of the protocol in a frame format according to a third layer of the protocol, transmitting the data packet from the computer system to the external printing device according to the first layer of the protocol; and decoding the data packet in accordance with the second layer of the protocol. The protocol can be defined to include three layers. In that protocol, a first layer may define transmission line, transmitters, and receivers for transmission, the second layer may define encoding and decoding, and the third layer may define a frame format of the data packet.

Abstract: Systems and techniques for printing on a workpiece. In one implementation, a data pump is used to create a packet of image data for a print head assembly. The data pump includes multiple state machines to receive image data from an image buffer on a computer, and a serializer to gather image data from each of the state machines. Each of the state machines is configured to send image data to the serializer at a different instance in time. The serializer is configured to arrange the gathered image data according to when the serializer received the image data from each of the state machines. The data pump also includes an optical fiber communication interface to connect with a communication channel.

Abstract: An apparatus, method, and a fluid ejection system for detecting electrical shorts in piezoelectric printheads are described. An apparatus includes a piezoelectric actuator, a transistor whose drain is connected to the piezoelectric actuator, a diode that is connected to a source and the drain of the transistor, a detection circuit configured to detect whether a voltage at the drain of the transistor is above a predefined voltage, and a disabling circuit configured to turning off the transistor in response to detecting that voltage at the drain of the transistor is above the predefined voltage.

Abstract: A fluid ejector includes a fluid ejection module and an integrated circuit element. The fluid ejection module includes a substrate having a plurality of fluid paths, a plurality of actuators, and a plurality of conductive traces, each actuator configured to cause a fluid to be ejected from a nozzle of an associated fluid path. The integrated circuit element is mounted on the fluid ejection module and is electrically connected with the conductive traces of the fluid ejection module such that an electrical connection of the module enables a signal sent to the fluid ejection module to be transmitted to the integrated circuit element, processed on the integrated circuit element, and output to the fluid ejection module to drive the actuator.

Abstract: Techniques, systems, and computer program products that facilitate image printing. A technique may include receiving an image to be printed, using a first software component to selectively pre-process the image depending on a format of the image, and using a second software component to generate image queues from the pre-processed image. In that technique, each image queue includes at least one portion of image data associated with an association of print elements that corresponds to a configuration of print elements at a printing device. The technique may be implemented in a scalable system, by having multiple first software components and multiple second software components, where each of the first and/or second components can reside on a separate computer system.

Abstract: Systems and techniques for printing on a workpiece. In one implementation, a data pump is used to create a packet of image data for a print head assembly. The data pump includes multiple state machines to receive image data from an image buffer on a computer, and a serializer to gather image data from each of the state machines. Each of the state machines is configured to send image data to the serializer at a different instance in time. The serializer is configured to arrange the gathered image data according to when the serializer received the image data from each of the state machines. The data pump also includes an optical fiber communication interface to connect with a communication channel.