Abstract: A printing apparatus has a transfer member to receive an image and transfer the image to a substrate, and an airflow management unit disposed adjacent to the transfer member to define a channel between the transfer member and the airflow management unit. The airflow management unit has an injection mechanism to inject airflow into the channel, a suction mechanism to remove the airflow from the channel, and a vortex generator to generate a vortex within the channel.

Abstract: An example method comprises identifying, by a processor, a gap in a housing of a printing apparatus and positioning an inlet of a conduit inside the housing proximate the gap. The inlet is fluidly connected to a fan, and the fan is powered to create a pressure differential across the housing to minimize the amount of air inside the housing being able to escape the housing via the gap.

Abstract: Disclosed is a method to mitigate deterioration of printing fluid in a tank of a printer. The method comprises: draining printing fluid from a tank of a printer, and stopping the draining before the tank is empty, wherein the printing fluid comprises solids suspended in imaging oil, filtering the printing fluid drained from the tank, to separate at least some of the solids from the imaging oil, passing the filtered imaging oil to a reservoir; and then passing imaging oil from the reservoir to the tank. Also disclosed is a printer and a system to perform the method.

Abstract: A print apparatus is disclosed. The print apparatus comprises a container-receiving unit for receiving a reusable print agent container; a print agent reservoir for storing print agent to be consumed by the print apparatus during a printing operation; a pump for transferring print agent between a reusable print agent container positioned in the container-receiving unit and the print agent reservoir; and processing circuitry. The processing circuitry is to operate the pump to transfer print agent of a first concentration from the reusable print agent container to the print agent reservoir; and, responsive to determining that a volume of print agent of the first concentration in the reusable print agent container has fallen below a threshold volume, operate the pump to transfer a volume of print agent of a second, lower concentration from the print agent reservoir to the reusable print agent container. A method and a machine-readable medium are also disclosed.

Abstract: Disclosed is a method to mitigate deterioration of printing fluid in a tank of a printer. The method comprises: draining printing fluid from a tank of a printer, and stopping the draining before the tank is empty, wherein the printing fluid comprises solids suspended in imaging oil, filtering the printing fluid drained from the tank, to separate at least some of the solids from the imaging oil, passing the filtered imaging oil to a reservoir; and then passing imaging oil from the reservoir to the tank. Also disclosed is a printer and a system to perform the method.

Abstract: Herein is disclosed a method for concentrating a liquid electrostatic ink composition, the method comprising replacing a first liquid carrier in a liquid electrostatic ink composition with a second liquid carrier, wherein the liquid electrostatic ink composition comprises chargeable toner particles dispersed in the first liquid carrier; and removing the second liquid carrier to produce a concentrated liquid electrostatic ink composition, wherein the second liquid carrier has a boiling point below 100° C. and wherein the second liquid carrier has a lower boiling point than the first liquid carrier. Also disclosed herein is a concentrated liquid electrostatic ink composition producible according to the method.

Abstract: An example method comprises identifying, by a processor, a gap in a housing of a printing apparatus and positioning an inlet of a conduit inside the housing proximate the gap. The inlet is fluidly connected to a fan, and the fan is powered to create a pressure differential across the housing to minimize the amount of air inside the housing being able to escape the housing via the gap.

Abstract: Disclosed is a method to mitigate deterioration of printing fluid in a tank of a printer. The method comprises: draining printing fluid from a tank of a printer, and stopping the draining before the tank is empty, wherein the printing fluid comprises solids suspended in imaging oil, filtering the printing fluid drained from the tank, to separate at least some of the solids from the imaging oil, passing the filtered imaging oil to a reservoir; and then passing imaging oil from the reservoir to the tank. Also disclosed is a printer and a system to perform the method.

Abstract: A print apparatus is disclosed. The print apparatus comprises a container-receiving unit for receiving a reusable print agent container; a print agent reservoir for storing print agent to be consumed by the print apparatus during a printing operation; a pump for transferring print agent between a reusable print agent container positioned in the container-receiving unit and the print agent reservoir; and processing circuitry. The processing circuitry is to operate the pump to transfer print agent of a first concentration from the reusable print agent container to the print agent reservoir; and, responsive to determining that a volume of print agent of the first concentration in the reusable print agent container has fallen below a threshold volume, operate the pump to transfer a volume of print agent of a second, lower concentration from the print agent reservoir to the reusable print agent container. A method and a machine-readable medium are also disclosed.

Abstract: Disclosed is a method to mitigate deterioration of printing fluid in a tank of a printer. The method comprises: draining printing fluid from a tank of a printer, and stopping the draining before the tank is empty, wherein the printing fluid comprises solids suspended in imaging oil, filtering the printing fluid drained from the tank, to separate at least some of the solids from the imaging oil, passing the filtered imaging oil to a reservoir; and then passing imaging oil from the reservoir to the tank. Also disclosed is a printer and a system to perform the method.

Abstract: An example method of collecting liquid carrier from a vapour in a printing system includes: heating a vapour carrying a liquid carrier and passing the heated vapour carrying liquid carrier through a volume of liquid carrier. Liquid carrier carried in the heated vapour condenses into the volume of liquid carrier as it passes through the volume of liquid carrier.

Abstract: In an example, a condenser apparatus to condense vapored fluid has a gas inlet, a mesh, a cooling element, and a gas outlet. The mesh is configured to carry a layer of condensed fluid. The cooling element is configured to cool the layer of condensed fluid. The mesh is configured to let pass through vapored fluid and to create bubbles including vapored fluid in the layer of condensed fluid.

Abstract: In an example, a condenser apparatus to condense vapored fluid has a gas inlet, a mesh, a cooling element, and a gas outlet. The mesh is configured to carry a layer of condensed fluid. The cooling element is configured to cool the layer of condensed fluid. The mesh is configured to let pass through vapored fluid and to create bubbles including vapored fluid in the layer of condensed fluid.

Abstract: An example method of collecting liquid carrier from a vapour in a printing system includes: heating a vapour carrying a liquid carrier and passing the heated vapour carrying liquid carrier through a volume of liquid carrier. Liquid carrier carried in the heated vapour condenses into the volume of liquid carrier as it passes through the volume of liquid carrier.

Abstract: Capacitances are measured for a level measurement capacitive sensor (18) spanning from a lower end to a higher end of a fluid level measurement range (30), a first capacitive calibration sensor (20) below the fluid level measurement range (30), and a second capacitive calibration sensor (22) above the fluid level measurement range (30). A degree to which the lower end of the fluid level measurement range (30) is immersed in a first fluid and the upper end of the fluid level measurement range (30) is immersed in a second fluid is determined based on a capacitance of the level measurement capacitive sensor (18), a first calibration value characterizing the first fluid and derived from a capacitance of the first capacitive calibration sensor (20), and a second calibration value characterizing the second fluid and derived from a capacitance of the second capacitive calibration sensor (22).

Abstract: A method for determining a pump setpoint for delivering a desired volumetric flow rate of a substance through a channel comprises measuring a first volumetric flow rate through the channel for a first pump setpoint. The pump setpoint for delivering the desired volumetric flow rate is determined based on previously obtained performance curves of the pump and a flow resistance of the channel. Each performance curve represents the relation between flow rate and pressure at the pump's exit for a different setpoint. The flow resistance of the channel is determined based on said first volumetric flow rate and on the performance curves of the pump.

Abstract: Image forming apparatus and methods are disclosed which include identifying a first ink density of ink in an ink tank by a density sensor unit disposed in the ink tank. The image forming apparatus and methods also include identifying an ink weight of ink in an intermediate reservoir by a weight sensor unit. The image forming apparatus and methods also include determining a second ink density of the ink in the intermediate reservoir based at least on the identified first ink density by the density sensor unit and the identified ink weight of the ink in the intermediate reservoir by the weight sensor unit.

Abstract: An image forming system includes a segregation tank to store a first imaging oil having a first percent purity, a reservoir to store a second imaging oil having a second percent purity, a slope identification module to identify a first slope value, and a slope comparison module to determine whether the first slope value is at least one of equal to, greater than, and less than a threshold slope value within a threshold slope range. The image forming system also includes a ratio adjustment module to obtain a variable ratio value corresponding to a ratio of a first amount of the first imaging oil to a second amount of the second imaging oil based on a determination by the slope comparison module.

Abstract: Image forming apparatus and methods are disclosed which include identifying a first ink density of ink in an ink tank by a density sensor unit disposed in the ink tank. The image forming apparatus and methods also include identifying an ink weight of ink in an intermediate reservoir by a weight sensor unit. The image forming apparatus and methods also include determining a second ink density of the ink in the intermediate reservoir based at least on the identified first ink density by the density sensor unit and the identified ink weight of the ink in the intermediate reservoir by the weight sensor unit.

Abstract: A method includes moving a first end portion of a charging member with respect to a photoconductive member to obtain a first electrical discharge event corresponding to conduction of an electrical current from the charging member to the photoconductive member. The method also includes identifying a first adjustment value corresponding to a distance in which the first end portion moved toward the photoconductive member to obtain the first electrical discharge event. The method also includes moving a second end portion of the charging member with respect to the photoconductive member to obtain a second electrical discharge event corresponding to conduction of an electrical current from the charging member to the photoconductive member. The method also includes identifying a second adjustment value corresponding to a distance in which the second end portion moved toward the photoconductive member to obtain the second electrical discharge event.