A liquid ejection head includes a print element substrate having an ejection port surface in which a plurality of ejection ports are arranged and a temperature control unit that controls a temperature of the ejection port surface. The print element substrate ejects a liquid from the plurality of ejection ports onto a medium moved by the liquid ejection head relatively to the liquid ejection head. The ejection port surface includes a region on a downstream side of the ejection port surface in a direction in which the medium relatively moves when the medium is viewed from the liquid ejection head, and includes a region on an upstream side of the ejection port surface in the relative moving direction. The temperature control unit control the temperature of the ejection port surface so that a temperature of the downstream side region becomes higher than a temperature of the upstream side region.

Systems and method of maintaining a uniform temperature distribution in an inkjet head. The inkjet head includes a plurality of ink channels that jet droplets of a liquid material onto a medium using piezoelectric actuators. A temperature controller includes a non-jetting pulse generator that provides non-jetting pulses to one or more of the piezoelectric actuators to generate heat. The non-jetting pulses cause the piezoelectric actuators to actuate without jetting a droplet from its corresponding ink channel.

A print apparatus is disclosed. The print apparatus comprises a plurality of printing elements; and a temperature control unit, controllable by processing circuitry, to increase an operating temperature of a first printing element in the plurality of printing elements by a defined amount relative to an operating temperature of a second printing element in the plurality of printing elements. A method and a machine-readable medium are also disclosed.

A distance between the first circuit and the second circuit is a first distance, a distance between the first circuit and the temperature detection circuit is a second distance longer than the first distance, and a distance between the second circuit and the temperature detection circuit is a third distance longer than the first distance.

In one example, a warming system for a region of multiple ejector elements on an inkjet printhead includes a warming circuit having a heating element distinct from any of the ejector elements and a controller programmed to selectively energize the heating element only upon determining none of the ejector elements in the region is active.

A printing apparatus includes a liquid ejecting unit capable of ejecting ink, which is a liquid, onto a medium and capable of reciprocating in a width direction (X-axis direction) of the medium, a medium support unit that supports the medium on a support face, a medium width detection unit that detects a width of the medium supported on the support face, a plurality of heating units that are provided along the width direction of the medium and heat the medium support unit, and a control unit capable of individually controlling the plurality of heating units. The control unit controls an output of each of the heating units in accordance with the width of the medium detected by the medium width detection unit.

A thermal inkjet printing device includes a fluidic die having a thermal sensor and a processor coupled to the fluidic die. The processor is to receive temperature data from the thermal sensor and determine a flow rate of liquid printing agent through the fluidic die based on the temperature data and an operating parameter for the fluidic die.

An embodiment of the present invention provides an ink jet printing apparatus including: a print head including a printing element array provided with printing elements each configured to generate thermal energy required to eject an ink, a supply flow channel provided along the printing element array and configured to supply the ink to the respective printing elements, an opening provided to the supply flow channel and configured to cause the ink to flow in, and heating units provided along the supply flow channel and configured to heat the ink inside the supply flow channel; and a heating control unit configured to carry out heating control of the heating units based on a heating pattern determined based on heating intensity distribution, the heating intensity distribution representing heating intensities corresponding to the respective heating units and representing the heating intensities corresponding to positions in a direction of the printing element array.

A printer includes an ink ejecting section that ejects ink from a nozzle, an ink circulation path including an ink flow path through which the ink can be supplied to an ink ejecting section and an ink return path through which the ink supplied to the ink ejecting section is returned, a warming device including a temperature control module provided in the ink circulation path, where the warming device can heat the ink in the temperature control module, and a feed pump that can flow the ink in the ink circulation path, wherein the flow rate of the ink, in the ink circulation path, heated by the warming device is adjusted.

A printing apparatus that performs printing by using a print head includes a first power supply, a second power supply, and a control unit. The first power supply supplies a first voltage to the print head through a first supply line. The second power supply supplies a second voltage to the print head through a second supply line. The control unit supplies the first voltage from the first power supply without supplying a voltage from the second power supply at the time of an inspection of the print head, and executes a process action concerning a current leakage when a voltage exceeding a predetermined first threshold is generated on the second supply line.