Hp Indigo B.v.

Hewlett-Packard Development Company, L.p.

Vitaly Portnoy

Michel Assenheimer

Amiran Lavon

Yoav Nachmias

Eric G Nelson

Amir Ofir

Maya Bar-Sadeh

Ido Finkelman

Liran Fanny Haim

Brian Schmitz Tani

Nailson Boaz Costa Leite

Miriel Cohen

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 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

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 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.

Wet null cycle printing

In an example, a method of controlling voltage applied to a print blanket within a printing device includes printing a print job. During the printing, a null cycle trigger is received. In response to the trigger, a print blanket bias voltage is reduced from a print bias level to a null bias level.

Adjustments to print blanket bias voltages

An apparatus is provided for controlling a liquid electrophotography printer (LEP). The LEP may include a plurality of ink developers, IDs, to transfer charged ink to a photoreceptor, by virtue of a potential difference between the engaged ID and the photoreceptor selectively dischargeable to allow an image to be formed on a print medium in use through printing a spread of plural color separations thereon each corresponding to ink from one of a plurality of engaged IDs. the apparatus may comprise a print controller to, in use monitor an order of color separations to be printed onto the print medium. The print controller may also detect in the order of color separations an empty separation of an ID followed by a printing separation of the same ID, an empty separation representing a separation in which no image is formed on the photoreceptor and the engaged ID is at a voltage different to the voltage of the ID for a printing separation so as to, in the empty separation, substantially wet the photoreceptor and substantially not transfer ink thereto. The print controller may also, in response to the detection, replace in the order of the color separations the ID for the empty separation with a different ID.

Empty separation printing

A photo drum may be to receive a color separation. A controller may be to change a location of the color separation on the photo drum from a first location to a second location when a separation location history for the color separation is outside of a threshold range.

Growing community of inventors

Ness Ziona, Israel

Vitaly Portnoy