A method of operating a printing system includes identifying groups of nozzles of a plurality of nozzles of a printhead device. The method also includes ejecting fluid drops by the printhead device from nozzles thereof and along corresponding firing paths. The method also includes controlling movement of a detector carriage including a plurality of drop detectors of a drop detector array with respect to the printhead device by a control module to align each one of the drop detectors with the respective firing paths corresponding to the respective nozzles at a predetermined time. The method also includes sensing the firing paths corresponding to the nozzles to detect a presence of the fluid drops by the drop detectors such that each one of the drop detectors senses at a same time a respective firing path corresponding to a respective nozzle for a plurality of groups of nozzles.

In an implementation, a printhead includes a printhead die molded into a molding. The die has a front surface exposed outside the molding to dispense fluid drops through nozzles and an opposing back surface covered by the molding except at a channel in the molding through which fluid may pass directly to the back surface. The die also has a nozzle health sensor molded into the molding to detect defective nozzles in the printhead die.

A printer has a print head check unit that performs an ink ejection check to confirm whether or not ink is being ejected normally from nozzles, the printer sets a flag F to 1 so as to start an ink ejection check and starts a paper feed process. When the processes has been terminated, the printer starts printing. Accordingly, ink ejection check takes place concurrently with the paper feed process, the overall time required for the processes can be reduced. In this way, the overall time required for the processes of the ejection check of the print recording liquid and an image forming process can be reduced. Further, the ink ejection check may be performed in parallel with or partly overlapping with a process of receiving print data, a process of conversion into print data, a process of ejecting paper after printing, or a flashing process.

In some examples, a method includes, in response to a fluid firing unit being operated according to a normal printing mode, applying a first voltage to the fluid firing unit to fire the fluid firing unit during a printing operation. The method further includes determining, using a sensor, whether a predetermined condition is met, and in response to determining that the predetermined condition is met, operating the fluid firing unit according to a recovery mode in which a second voltage higher than the first voltage is applied to the fluid firing unit to clean the fluid firing unit.

A liquid discharging apparatus includes a liquid discharging head that discharges a liquid from a nozzle, a control circuit that controls a discharge operation of the liquid discharging head, a nozzle omission detection mechanism that detects a discharge fault of the nozzle, a maintenance mechanism that performs a maintenance operation, which ejects the liquid from the nozzle of the liquid discharging head, and a display device that displays a setting screen relating to the discharge operation of the liquid discharging head. The control circuit executes the discharge operation of the liquid discharging head on the basis of the operation mode selected by a user using the operation mode selection screen for selecting a plurality of operation modes in which a situation in which a transition to the maintenance operation is performed in a case in which the discharge fault is detected, differs, on the display device.

A system includes a processor that executes computer executable components stored in a memory. The system includes a first component to receive data generated by at least one sensor. The system further includes a second component to generate an array that determines between activating one of a purge routine and a diagnostic routine on a printhead based on the array. The array is a function of the data. The system further includes a control component operable to selectively activate the purge routine on the printhead based on the determination.

When inspection driving is performed by a liquid ejection head, a signal output circuit outputs a determination signal indicating whether a nozzle is an abnormal nozzle. The inspection driving is driving the liquid ejection head to eject liquid from the nozzle for checking whether the nozzle is the abnormal nozzle. A recovery device performs a recovery operation of discharging liquid from the nozzle. A controller is configured to: in response to receiving a first signal, perform the inspection driving and, in response to determining that the determination signal transmitted from the signal output circuit indicates that the abnormal nozzle exists, store flag information in a memory, the flag information indicating that the recovery operation needs to be performed; and in response to receiving a second signal different from the first signal and determining that the memory stores the flag information, control the recovery device to perform the recovery operation.

A liquid ejection apparatus includes a liquid ejection head having a plurality of nozzles, a determination circuit, a clock, and a controller. The controller is configured to determine whether the clock is in an on or off state. In response to determining that the clock is in an on state, the controller is configured to perform an inspection process at a first time. In the inspection process, the controller drives the liquid ejection head to eject liquid from a nozzle of the plurality nozzles and receive a determination signal that is output from the determination circuit in response to ejection of liquid from the nozzle of the plurality of nozzles. In response to determining that the clock is in an off state, the controller is configured to perform the inspection process at a predetermined time that is a time after the clock is returned to an on state.

A liquid ejection apparatus includes a first circuit to output a determination signal indicating that ejecting ink is in failure, a second circuit to output a temperature signal indicating a temperature, a recovery device to perform a recovery operation, and a controller. The controller causes a recovery device to perform a first recovery operation based on a first failure-nozzle data in response to determining that a first temperature and a second temperature satisfy a predetermined condition.

Ink is circulated through a circulation flow path between a print head and an ink tank. Detection operation for detecting an ink ejection state in an ejection opening in the print head is performed. The ink circulation and the detection operation are simultaneously performed by performing the detection operation in response to a start of the ink circulation.