Abstract: Certain examples relate to controlling recirculation processes in a printing apparatus. An example printing material cartridge includes a reservoir storing printing material to supply a printing apparatus; memory; and instructions for controlling a recirculation process in the printing apparatus, the instructions stored in the memory, the recirculation process to cause the printing material to move between the reservoir and a second printing material cartridge, the second printing material cartridge separately replaceable from the printing material cartridge in the printing apparatus.

Abstract: An example printing fluid circulation system includes a first circuit to circulate a printing fluid through a printhead in a first direction and a second circuit to circulate the printing fluid through the printhead in a second direction opposite to the first direction. The first circuit is activated during a first mode to circulate the printing fluid from a first reservoir to a second reservoir. The second circuit is activated during a second mode different from the first mode to circulate the printing fluid from the first reservoir to the second reservoir.

Abstract: Certain examples relate to mixing and/or supply cartridges for printing apparatus. One example implementation includes a reservoir to receive printing material from a printing apparatus and to return the received printing material to the printing apparatus. A storage medium stores a reservoir printing material level parameter indicative of the amount of printing material in the reservoir; a recirculation cycle counter indicative of the number of recirculation events experienced by the cartridge; a maximum recirculation cycle parameter indicative of the maximum number of recirculation events that may be experienced by the cartridge.

Abstract: A printing device and method is described comprising: selectively generating a negative fluid pressure between one of one or more printing fluid supplies and a first one of first and second ports of a printhead; selectively generating a positive fluid pressure between one of said printing fluid supplies and a second one of the first and second ports of the printhead; and providing a first pulsed signal to a first priming pump associated with a first one of the first and second ports, wherein the first one of said first and second ports of the printhead is opened under the control of said first priming pump, such that printing fluid within the printhead exits the printhead through the first one of the first and second ports.

Abstract: A printing fluid delivery system comprising a fluid pump having an inlet and an outlet, a valve connected to the outlet of the fluid pump, and a controller to close the valve while the fluid pump is driven to increase the pressure at the outlet of the fluid pump based on a service condition and to open the valve based on a predefined relief condition to relieve the pressure at the outlet of the fluid pump.

Abstract: The present disclosure refers to a method of monitoring a fluid supply system, the system including a collapsible fluid reservoir to contain a supply of fluid and an outer container to enclose the collapsible fluid reservoir and to receive pressurized gas that pressurizes the supply of fluid, the method comprising a controller to: control a gas pressure pump to feed the fluid to or from the fluid reservoir, the gas pressure pump operating in pressurization cycles; monitor a parameter of the pressurization cycles; and determine a fill state of the fluid reservoir as a function of the monitored parameter.

Abstract: An example printing fluid circulation system includes a first circuit to circulate a printing fluid through a printhead in a first direction and a second circuit to circulate the printing fluid through the printhead in a second direction opposite to the first direction. The first circuit is activated during a first mode to circulate the printing fluid from a first reservoir to a second reservoir. The second circuit is activated during a second mode different from the first mode to circulate the printing fluid from the first reservoir to the second reservoir.

Abstract: An example printing material cartridge includes a reservoir storing printing material to supply a printing apparatus and a storage medium storing process instructions for controlling the recirculation process in the printing apparatus.

Abstract: An example printing fluid circulation circuit for a printing system comprises a first circuit port to supply printing fluid to, or receive printing fluid from, a first fluid port of a printhead and a second circuit port to supply printing fluid to, or receive printing fluid from, a second fluid port of a printhead. The printing fluid circulation circuit is to operate in a first mode to concurrently supply printing fluid from the first reservoir to the first circuit port and from the second circuit port to a second reservoir, and in a second mode to concurrently supply printing fluid from the first reservoir to the second circuit port and from the first circuit port to the second reservoir.

Abstract: Certain examples relate to controlling recirculation processes in a printing apparatus. An example printing material cartridge includes a reservoir storing printing material to supply a printing apparatus; memory; and instructions for controlling a recirculation process in the printing apparatus, the instructions stored in the memory, the recirculation process to cause the printing material to move between the reservoir and a second printing material cartridge, the second printing material cartridge separately replaceable from the printing material cartridge in the printing apparatus.

Abstract: Certain examples relate to mixing and/or supply cartridges for printing apparatus. One example implementation includes a reservoir to receive printing material from a printing apparatus and to return the received printing material to the printing apparatus. A storage medium stores a reservoir printing material level parameter indicative of the amount of printing material in the reservoir; a recirculation cycle counter indicative of the number of recirculation events experienced by the cartridge; a maximum recirculation cycle parameter indicative of the maximum number of recirculation events that may be experienced by the cartridge.

Abstract: Certain examples relate to mixing and/or supply cartridges for printing apparatus. One example implementation includes a reservoir to receive printing material from a printing apparatus and to return the received printing material to the printing apparatus. A storage medium stores a reservoir printing material level parameter indicative of the amount of printing material in the reservoir; a recirculation cycle counter indicative of the number of recirculation events experienced by the cartridge; a maximum recirculation cycle parameter indicative of the maximum number of recirculation events that may be experienced by the cartridge.

Abstract: A printing device and method is described comprising: selectively generating a negative fluid pressure between one of one or more printing fluid supplies and a first one of first and second ports of a printhead; selectively generating a positive fluid pressure between one of said printing fluid supplies and a second one of the first and second ports of the printhead; and providing a first pulsed signal to a first priming pump associated with a first one of the first and second ports, wherein the first one of said first and second ports of the printhead is opened under the control of said first priming pump, such that printing fluid within the printhead exits the printhead through the first one of the first and second ports.

Abstract: In an example, a pressure system includes a fluid movement device, a buffer reservoir coupled to the fluid movement device, and a first fluid interface coupled to the buffer reservoir. In that example, the first fluid interface is able to couple to a pressurizable chamber of a print fluid container (that can apply force on a print fluid bag of the print fluid container).

Abstract: Certain examples relate to mixing and/or supply cartridges for printing apparatus. One example implementation includes a reservoir to receive printing material from a printing apparatus and to return the received printing material to the printing apparatus. A storage medium stores a reservoir printing material level parameter indicative of the amount of printing material in the reservoir; a recirculation cycle counter indicative of the number of recirculation events experienced by the cartridge; a maximum recirculation cycle parameter indicative of the maximum number of recirculation events that may be experienced by the cartridge.

Abstract: Certain examples relate to controlling recirculation processes in a printing apparatus. One example implementation includes a printing material cartridge comprising a reservoir storing printing material to supply a printing apparatus and a storage medium storing process instructions for controlling the recirculation process in the printing apparatus.

Abstract: Operating a fluid delivering system in a printer, wherein the fluid delivering system comprises a fluid supply including a fluid bag which contains a fluid to be delivered to a fluid delivering tube connected to a printhead, and a closed pressurizing volume which surrounds the fluid bag to expel fluid from the fluid bag to the fluid delivering tube when applying pressure from a pressurizing system to the pressurizing volume, wherein pressure in the pressurizing system relative to atmosphere is measured by a first sensor, and wherein a second sensor provides an output signal which indicates a pressure difference between the pressurizing system and the fluid delivering tube, comprising disconnecting the pressurizing volume of the fluid supply from the pressurizing system, providing a connection of the pressurizing volume to atmosphere to transmit atmospheric pressure to the fluid, generating pressure in the pressurizing system, performing measurements of the pressure in the pressurizing system relative to atmos

Abstract: A differential pressure sensor is used for measuring or identifying a pressure difference, for example to determine a movement or speed of fluid in a fluid conduit or printer re-circulation conduit. The differential pressure sensor determines the difference between an air pressure and a fluid pressure, wherein the fluid is moving in a flow channel. The flow channel includes a surface conveying a fluid between a first port and second port. An opening in the surface of the flow channel provides a fluid communication between the differential pressure sensor and fluid. Moreover, the sensor is arranged in air communication with the pressure box, such as to allow the differential pressure sensor to identify the pressure difference between the air pressure in the pressure box and the fluid pressure in the flow channel.

Abstract: An example printing fluid circulation circuit for a printing system comprises a first circuit port to supply printing fluid to, or receive printing fluid from, a first fluid port of a printhead and a second circuit port to supply printing fluid to, or receive printing fluid from, a second fluid port of a printhead. The printing fluid circulation circuit is to operate in a first mode to concurrently supply printing fluid from the first reservoir to the first circuit port and from the second circuit port to a second reservoir, and in a second mode to concurrently supply printing fluid from the first reservoir to the second circuit port and from the first circuit port to the second reservoir.

Abstract: Operating a fluid delivering system in a printer, wherein the fluid delivering system comprises a fluid supply including a fluid bag which contains a fluid to be delivered to a fluid delivering tube connected to a printhead, and a closed pressurizing volume which surrounds the fluid bag to expel fluid from the fluid bag to the fluid delivering tube when applying pressure from a pressurizing system to the pressurizing volume, wherein pressure in the pressurizing system relative to atmosphere is measured by a first sensor, and wherein a second sensor provides an output signal which indicates a pressure difference between the pressurizing system and the fluid delivering tube, comprising disconnecting the pressurizing volume of the fluid supply from the pressurizing system, providing a connection of the pressurizing volume to atmosphere to transmit atmospheric pressure to the fluid, generating pressure in the pressurizing system, performing measurements of the pressure in the pressurizing system relative to atmos