Abstract: Examples include a method for priming a printhead that comprises a bag associated with a pump. A first control signal, which corresponds to a first target pressure, is applied to the pump. Directly after the application of the first control signal, a second control signal, which corresponds to a second target pressure, is applied to the pump. The second target pressure is lower than the first target pressure.

Abstract: Disclosed herein is a print head maintenance assembly, a printing device and a method of controlling a print head maintenance assembly in a printing device. The print head maintenance assembly comprises a maintenance cartridge comprising a positioning flag, wherein the maintenance cartridge is movable along a maintenance path in a direction of movement; and a sensor to detect the positioning flag to determine the position of the maintenance cartridge along the maintenance path.

Abstract: Methods to wipe a print head are described. In an example of a method, an amount of treatment fluid is determined based on a temperature of the print head and the print head is wiped with the determined amount of treatment fluid and a wiping medium.

Abstract: Example apparatus is disclosed, including apparatus for print head maintenance, the apparatus comprising a print mead maintenance device to perform a print head maintenance operation on a print head during a printing process, and a controller to cause the print head maintenance device to perform the print head maintenance operation with a parameter based on an amount of print agent applied by the print head.

Abstract: There is provided a maintenance apparatus to, while in a service zone, perform a cleaning operation of a set of printheads within a carriage. The maintenance apparatus comprises a cleaning structure and an actuation mechanism. The actuation mechanism is arranged to position the cleaning structure between an engaged configuration and a disengaged configuration. The disengaged configuration is activated by a first triggering element associated to the carriage interacting with the actuation mechanism subsequent to a cleaning operation. The engaged configuration is activated by a second triggering element as the carriage moves away from the service zone.

Abstract: There is provided a maintenance apparatus to, while in a service zone, perform a cleaning operation of a set of printheads within a carriage. The maintenance apparatus comprises a cleaning structure and an actuation mechanism. The actuation mechanism is arranged to position the cleaning structure between an engaged configuration and a disengaged configuration. The disengaged configuration is activated by a first triggering element associated to the carriage interacting with the actuation mechanism subsequent to a cleaning operation. The engaged configuration is activated by a second triggering element as the carriage moves away from the service zone.

Abstract: Example apparatus is disclosed, including apparatus for print head maintenance, the apparatus comprising a print mead maintenance device to perform a print head maintenance operation on a print head during a printing process, and a controller to cause the print head maintenance device to perform the print head maintenance operation with a parameter based on an amount of print agent applied by the print head.

Abstract: Disclosed herein is a print head maintenance assembly, a printing device and a method of controlling a print head maintenance assembly in a printing device. The print head maintenance assembly comprises a maintenance cartridge comprising a positioning flag, wherein the maintenance cartridge is movable along a maintenance path in a direction of movement; and a sensor to detect the positioning flag to determine the position of the maintenance cartridge along the maintenance path.

Abstract: Methods to wipe a print head are described. In an example of a method, an amount of treatment fluid is determined based on a temperature of the print head and the print head is wiped with the determined amount of treatment fluid and a wiping medium.

Abstract: In an example, a print apparatus includes a printhead carriage to receive a printhead comprising a print agent ejection nozzle, a drop detector to acquire a signal indicative of variations in a parameter detected by the drop detector over a period of drop detection, a memory to hold a print agent ejection signature, and processing circuitry. The processing circuitry includes a convolution module to convolve the drop detector signal with the print agent ejection signature, and the processing circuitry is to determine, from an output of the convolution module, an indication of similarity between the drop detector signal and the print agent ejection signature.

Abstract: In an example, a printhead maintenance apparatus includes a pump, a current monitor and processing circuitry. The pump may be provided to increase a pressure in a printhead, and the current monitor may monitor a current consumption of the pump. The processing circuitry may determine a rate of change of current consumption of the pump, and compare the rate of change of current consumption to a predetermined threshold.

Abstract: In an example, a printhead maintenance apparatus includes a pump, a current monitor and processing circuitry. The pump may be provided to increase a pressure in a printhead, and the current monitor may monitor a current consumption of the pump. The processing circuitry may determine a rate of change of current consumption of the pump, and compare the rate of change of current consumption to a predetermined threshold.

Abstract: A print head monitoring system includes a fly-by spitting station, the fly-by spitting station receiving droplet of printing agent from a print head when the print head passes over the fly-by spitting station, and a drop detector which is located at the fly-by spitting station.

Abstract: In an example, a print apparatus includes a printhead carriage to receive a printhead comprising a print agent ejection nozzle, a drop detector to acquire a signal indicative of variations in a parameter detected by the drop detector over a period of drop detection, a memory to hold a print agent ejection signature, and processing circuitry. The processing circuitry includes a convolution module to convolve the drop detector signal with the print agent ejection signature, and the processing circuitry is to determine, from an output of the convolution module, an indication of similarity between the drop detector signal and the print agent ejection signature.