Abstract: 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.

Abstract: 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.

Abstract: In one example a method comprises moving, by a processor, a photoreceptor of a print apparatus. The photoreceptor is movable between a fully engaged position in which the photoreceptor is to engage a transfer member of the print apparatus to transfer an image from the photoreceptor to the transfer member and a fully disengaged position in which the photoreceptor is remote from the transfer member. The method comprises moving, by a processor, the photoreceptor to an intermediate position between the fully engaged and fully disengaged positions. The method comprises engaging, by a processor, a cleaning system of the print apparatus with the photoreceptor when the photoreceptor is in the intermediate position.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: There is disclosed a device such as a printer or temperature control device for a printer. The device may comprise a photoreceptor. The device may further comprise a heat exchanger to regulate a temperature of the photoreceptor. The device may further comprise a temperature regulator to measure a temperature of a surface of the photoreceptor and control the heat exchanger based on the measured temperature. The device may further comprise a superior temperature controller to, during a pre-print phase of a print action, inhibit the control of the heat exchanger by the temperature regulator and control the heat exchanger to provide a specified amount of heat exchange.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus comprises a counter to determine a number of impressions already printed by a component in a printing device; and a controller, coupled to the counter, to use the number of impressions already printed and information relating to lifespan performance of the component in a printing device, to determine an estimated number of remaining impressions for the component, and to communicate the estimated number of remaining impressions to a user. The information relating to lifespan performance provides an indication of an estimated number of remaining impressions, for the number of impressions already printed, derived from statistical lifespan data selected in dependence on a lifespan threshold corresponding to the number of impressions already printed.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.