An example device in accordance with an aspect of the present disclosure includes a first reservoir for a printable composition, a pump fluidically coupled to the first reservoir and a second reservoir, and a valve to prevent backflow from the second reservoir to the pump. The valve is to selectively isolate the second reservoir from the pump based on a threshold pump pressure under which the valve is to close.

A print module includes: a body housing first and second opposed printed circuit boards (PCBs), each of the first and second PCBs having heat-generating electronic components; an air inlet and an air outlet positioned towards an upper part of the body; an air pathway extending between the air inlet and the air outlet; a plurality of heatsinks, each heatsink being thermally coupled with one of the heat-generating components and having an array of cooling fins extending into the air pathway; and an inkjet printhead receiving power and print data from at least one of the first and second PCBs. The inkjet printhead is positioned toward a lower part of the print module.

An inkjet printer includes: an inkjet printhead; an ink line connected to the printhead; and a compliance fluidically communicating with the ink line. The compliance includes sealed flexible bellows configured for dampening ink pressure fluctuations in the ink line.

Priming printheads can, in various examples, include moving a movable member of a printhead from a first position to a second position, measuring a response time of the movable member to move from the first position to the second position, and identifying the printhead as primed.

A liquid ejecting head unit includes a drive unit for ejecting a liquid inside a pressure chamber from a nozzle opening which communicates with the pressure chamber, a common liquid chamber which communicates with a plurality of the pressure chambers, a bubble return flow path for communicating with the common liquid chamber and discharging bubbles inside the common liquid chamber, a confluence point which communicates with a plurality of the bubble return flow paths, a collective return flow path for communicating with the confluence point and discharging the bubbles inside the plurality of bubble return flow paths, and a one-way valve which is provided part way down the bubble return flow path.

An ink circulation system, including an ink cartridge, an ink tank, an ink pump, first, second, and third valves, a print head, a heating assembly, and a positive-negative pressure assembly, is provided. The ink cartridge has an output pipeline and an ink cartridge valve. The ink tank is disposed on one side of the ink cartridge and connected to the output pipeline. The ink pump is connected to the output pipeline and the ink tank through an ink pipeline. The first valve is connected to the ink tank through a first pipeline. The second valve is disposed on the output pipeline. The third valve is connected to the output pipeline and the ink pipeline through a return pipeline. The print head is connected to the ink tank and the return pipeline. The heating assembly is disposed in the ink tank. The positive-negative pressure assembly is connected to the first pipeline.

In accordance with an embodiment, a liquid circulation module comprises a liquid ejection head for ejecting liquid, a storage section connected with the liquid ejection head to store the liquid, a circulation section configured to circulate the liquid in a predetermined circulation path passing through the liquid ejection head and the storage section, a pressure detection section configured to detect pressure in the storage section, a pressure adjusting section configured to adjust pressure in the storage section, and a module controller configured to control a circulation operation of the circulation section and a pressure adjusting operation of the pressure adjusting section independently from a host controller arranged separately from the liquid circulation module and when communicating with the host controller.

An ink-jet printer including a conveyor, a carriage, a recording head, a power supply, an ink receiver, a command receiver, and a controller, is provided. The controller executes the steps of: determining a discharge ink amount that should be discharged to the ink receiver; raising a drive voltage to a first voltage when the discharge ink amount is less than a first threshold value, and raising the drive voltage to a second voltage when the discharge ink amount is the first threshold value or more; performing a flushing process; based on the flushing process after having raised the drive voltage to the second voltage having finished in the case of having raised the drive voltage to the second voltage, stepping down the drive voltage from the second voltage to the first voltage; and based on the flushing process having finished and on the drive voltage being the first voltage, performing a printing process.

A print liquid supply sub-assembly, the print liquid supply sub-assembly to connect to a printer to provide a print liquid to the printer may include a print liquid output to connect to a print liquid input of the printer; a first fluidic channel upstream of the print liquid output comprising a first fluidic valve to prevent the print liquid from entering a supply container upstream of the first fluidic valve; and a second fluidic channel upstream of the print liquid output fluidically coupled to the first fluidic channel comprising a second fluidic valve to selectively prevent the fluid from passing out of the supply container downstream from the second fluidic valve.

A fluid supply component for a replaceable fluid supply may include a channel fluidically coupled to a pliable fluid supply bag; a ball housed within the channel; and a gasket to prevent movement of the ball into the fluid supply bag; wherein the valve prevents fluid from entering the fluid supply bag while the fluid supply bag imparts a negative fluidic pressure.