Hp Indigo B.v.

Hewlett-packard Development Company, L.p.

Hewlett-packard Indigo B.v.

Michel Assenheimer

Vitaly Portnoy

Amiran Lavon

Yoav Nachmias

Eric G Nelson

Dmitry Maister

Amir Ofir

Liran Fanny Haim

Dror Kella

Martin Chauvin

Ziv Gilan

Gideon Amir

Uri Lidai

Sagi Daren

Assaf Berman

Maya Bar-Sadeh

Barry J Oldfield

Doron Schlumm

Gil Bar-Haim

Sasi Moalem

Asaf Shoshani

Itzik Kent

Kobi Shkuri

Ido Finkelman

Giries Kadis

Elad Taig

Gilad Tzori

Yossi Cohen

Haggai Abbo

Peter Forgacs

Yossi Yaacobov

Brian Schmitz Tani

Nailson Boaz Costa Leite

Dorit Shalev

Naama Barak

Michael Levy

Uri Levy

Maya Bourla-Sadeh

Miriel Cohen

Orly Cohen

Roni Yehuda

A print apparatus is disclosed. The print apparatus includes a photoconductive surface to receive a latent image representative of an image to be printed onto a printable substrate; a charging component to apply a voltage is to be applied to the photoconductive surface as the charging component moves relative to the photoconductive surface; and processing circuitry to receive data indicative of a measurement of a first current resulting from the voltage applied by the charging component; determine, responsive to detecting an increase in the measured first current relative to a reference current, the increase being greater than a first defined threshold current, that there exists a point defect under affecting the latent image; and generate instruction data responsive to determining that there exists a point defect under affecting the latent image. A method and a machine-readable medium are also disclosed.

Determining the existence of point defects in print apparatuses

A printing device includes a printing engine to selectively output print material, a replaceable item of the printing engine, and a subsystem for the printing engine. A machine learning model is used to control controllable parameters of the subsystem for the printing engine, based on physical characteristic measurements of the printing device, to maximize a lifespan of the replaceable item.

Printing device parameter control using machine learning model, in order to maximize replaceable item lifespan

A computer-implemented method is disclosed. The method includes receiving a first indication that a first replaceable component of a print apparatus has been replaced; receiving, prior to any print impressions being made using the print apparatus since receiving the first indication, a second indication of an intention to replace a second replaceable component of the print apparatus; retrieving data regarding previous replacements of replaceable components of the print apparatus; determining, based on the retrieved data, whether or not replacement of the second replaceable component is to be restricted; and responsive to determining that replacement of the second replaceable component is to be restricted, restricting replacement of the second replaceable component. An apparatus and a machine-readable medium are also disclosed.

Restricting replacement of components

In an example, a method includes receiving, by at least one processor, an instruction to print a user specified printing task to at least one media sheet. Print operation instructions may be determined. Such print operation instructions may comprise instructions to control a print apparatus to print the user specified printing task and instructions to control a print apparatus to carry out at least one cleaning operation, wherein the cleaning operation comprises duplex printing a print media sheet.

Print operations comprising user specified printing tasks and cleaning operations

In one example, a method comprises measuring, by a processor, the flow rate of a cleaning fluid to clean at least a portion of a printing apparatus. The measured flow rate is compared to a desired flow rate. When the measured flow rate is outside of a first deviation from the desired flow rate, but within a second deviation from the desired flow rate, then the method in this example comprises changing the operation of a component of a printing apparatus.

Determining cleaning fluid flow at a print apparatus

A printing device having a heating apparatus arranged to heat an image substrate, a temperature sensor associated with the image substrate, and a processor communicatively coupled to the heating apparatus. During a simulation mode of the printing device, the processor determines the heating power of the heating apparatus, predicts a temperature of the image substrate based on the heating power, compares the predicted temperature to a measured temperature of the image substrate by the temperature sensor, determines a calibration offset when the measured temperature deviates from the predicted temperature, and selectively generates a control signal for use in calibrating the temperature sensor based on the calibration offset.

Calibration of a temperature sensor of a printing device

A printing device containing a heating apparatus that heats an image substrate, a temperature sensor associated with the image substrate and a processor communicatively coupled to the heating apparatus. The processor determines the heating power of the heating apparatus, compares the heating power to a predetermined power range, determines a status of the temperature sensor when the heating power is outside the predetermined power range, and triggers a response mode of the printing device based on the determined status of the temperature sensor.

Status of a temperature sensor of a printing device

In an example, a method for controlling termination of a print procedure subsequent to a node reset within print apparatus including a plurality of nodes includes identifying the node at which the reset occurred, and controlling operation within the print apparatus by way of a selected node. The selected node is different from the identified node and selected responsive to the identification of the identified node for operation of a component of the print apparatus as part of a termination procedure.

Print termination

A printing device includes a print blanket to transfer an ink image onto print media on an impression drum. Responsive to receiving a null cycle trigger during printing, the impression drum is repositioned to a null position to reduce contact between a print blanket and the impression drum.

Contact control of print blanket to impression drum

Certain examples described herein relate to splice detection. In certain cases, a splice is detected in a web being conveyed towards a transfer member of the printing system. In certain cases, a print frame is identified from a sequence of pending print frames using successive repeat lengths of the sequence and a distance of the splice from the transfer member. The identified print frame is to be transferred from the transfer member across the splice. In certain cases, writing of the identified print frame onto a photo-imaging plate of the printing system is deferred. In certain examples, the web is disengaged from the transfer member following transfer of an image of a print frame preceding the identified print frame. The web is re-engaged with the transfer member so as to transfer an image of the identified print frame to the web from the transfer member after the splice is conveyed beyond the transfer member.

Splice detection

According to examples, a method comprises receiving, at a processor, print job data relating to a print job to be performed by a print apparatus, the print job data defining order in which a plurality of colour separation images are to be transferred onto an imaging surface of the print apparatus. The method may comprise determining, based on the print job data, a number of null segments to be inserted into the print job and a location at which each null segment is to be inserted amongst the plurality of colour separation images. A print apparatus and a machine-readable machine are also disclosed.

Null segments in print jobs

Example implementations provide a method of controlling an ink developer used in electro-photography; the method comprising, following cessation of printing, varying a plurality of voltages associated with movement of ink within the ink developer at temporally disparate times.

Controlling ink developer voltages

An example system includes a power supply. The power supply is electrically coupled to an electrode, a developer roller, and a cleaner roller. The system also includes a controller. The controller is to instruct the power supply to reduce, at a first time, a magnitude of an electrode voltage supplied to the electrode. The controller also is to instruct the power supply to set, at a second time, a developer roller voltage and a cleaner roller voltage each to about a wet null voltage.

Wet null voltages

In one example of the disclosure, it is determined that an amount of print agent remaining in a print agent container of a print apparatus is below a threshold level. An amount of print solution is transferred from a print solution reservoir of the print apparatus, or an amount of print solution solvent is transferred from a solvent reservoir of the print apparatus, into the print agent container. At least some of the remaining print agent is caused to dissolve into the amount of print solution or print solution solvent to forma rinse solution. The rinse solution is transferred from the print agent reservoir to the print solution reservoir.

Transferring print agent in print apparatus

In an example, a method of wetting a print blanket includes receiving a null cycle trigger during a printing session. The method also includes maintaining printing voltages on a forecast BID (binary ink developer) that has been prepared to print a next color separation onto a photoreceptor, and applying wet null voltages to a non-forecast BID. The method then includes engaging the non-forecast BID with the photoreceptor to transfer fluid other than ink to the photoreceptor during the null cycle.

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Kfar Sava, Israel

Michel Assenheimer