In an inkjet printer, when an estimated viscosity of a first ink in a first nozzle is less than a threshold value, a power supply generates a first drive voltage, and when the estimated viscosity of the first ink is the threshold value or more, the power supply generates a second drive voltage higher than the first drive voltage. Moreover, at a time of vibrating a meniscus of a second ink in a second nozzle, when the first drive voltage is generated by the power supply, there is output to a drive element a first meniscus vibration signal, and when the second drive voltage is generated, there is output a second meniscus vibration signal by which energy imparted to the second ink by the drive element when applied to the drive element at an identical voltage level will be smaller compared to the first meniscus vibration signal.

An inkjet printer configures the printheads in a printhead module in an orientation that attenuates a temperature differential between the ink drops ejected by adjacent printheads at a stitch area between the adjacent printheads. The reduced temperature differential helps ensure that the contrasts between the two inks ejected by the adjacent printheads is sufficiently similar that image quality is not adversely impacted.

Devices and method for performing temperature measurements in a printhead. In one embodiment, a printhead includes at least one row of jetting channels configured to jet droplets of a print fluid using piezoelectric actuators. A drive circuit includes an input voltage generator that applies a step voltage to a piezoelectric actuator of a jetting channel, and an output voltage detector that detects an output voltage across the piezoelectric actuator over time in response to the step voltage. The drive circuit also includes a temperature detector that determines a voltage response to the step voltage at the piezoelectric actuator based on the output voltage over time, and determines a temperature measurement for the piezoelectric actuator based on the voltage response of the piezoelectric actuator.

A temperature acquisition section (acquisition module) acquires a temperature of an environment in which a printer device is used. A printing condition acquisition section (acquisition module) acquires information relating to printing conditions of the printer device. A conveyance load estimation section (estimation module) estimates a conveyance load when a stepping motor (motor) provided in the printer device conveys a printing paper (print medium) based on the information acquired by the temperature acquisition section and the printing condition acquisition section. A current value setting section (setting module) sets a current value to be applied to the stepping motor based on the conveyance load estimated by the conveyance load estimation section. A motor control section (control module) controls the stepping motor by applying the current value set by the current value setting section to the stepping motor.

A drive unit is configured to generate a drive signal for driving a liquid ejecting head unit. The drive unit includes a drive board on which a drive circuit configured to generate the drive signal is mounted; a thermal conductive material that is in contact with the drive circuit on an opposite side in relation to the drive board; a water cooling mechanism that is in contact with the thermal conductive material on an opposite side in relation to the drive circuit; a pump that causes liquid in the water cooling mechanism to flow; and a control circuit that controls operation of the pump. The control circuit switches a direction in which the pump causes the liquid to flow between a forward direction and a reverse direction that is an opposite of the forward direction.

According to an embodiment of this invention, an element substrate which is included in a printhead, comprises: a heater configured to heat ink and discharge ink from a nozzle; a temperature sensor provided in correspondence with the heater; an electric current source configured to energize the temperature sensor with an electric current based on an electric current value specified by an externally input first signal; and a determination circuit configured to determine an ink discharge status of the nozzle based on a voltage output from the temperature sensor energized with the electric current and a threshold voltage specified by an externally input second signal, and output a determination result signal.

A printing apparatus includes a printhead having a nozzle to eject liquid and an actuator associated with the nozzle. A controller is provided to activate a recovery sequence including heating the printhead without firing drops in a first phase, activating the actuator to fire 1000 drops or more from the nozzle in a second phase after the first phase, and heating the printhead and applying pressure to expel liquid from the nozzle in a third phase after the second phase.

Devices and method for performing temperature measurements in a printhead. In one embodiment, a printhead includes at least one row of jetting channels configured to jet droplets of a print fluid using piezoelectric actuators. A drive circuit includes an input voltage generator that applies a step voltage to a piezoelectric actuator of a jetting channel, and an output voltage detector that detects an output voltage across the piezoelectric actuator over time in response to the step voltage. The drive circuit also includes a temperature detector that determines a voltage response to the step voltage at the piezoelectric actuator based on the output voltage over time, and determines a temperature measurement for the piezoelectric actuator based on the voltage response of the piezoelectric actuator.

The controller obtains temperature data based on a temperature sensor when the controller is in an energized state and stores temperature history information of the obtained temperature data in a storage. The controller determines whether there occurs a non-energized state after a previous purge operation, estimates the temperature data in the non-energized state based on the temperature history information when the non-energized state exists after previous execution of the purge operation, and sets a purge condition of a next purge operation based on an elapsed time from previous execution of the purge operation and the temperature history information stored in the storage, sets the purge condition based on the estimated temperature data in the non-energized state in addition to the elapsed time and the temperature history information when there exists the non-energized state after the previous execution of the purge operation.

An object of the present invention is to quickly correct a temperature sensor for an ejection head by, both efficiently and in a brief time, estimating a detected temperature of the temperature sensor for the ejection head in a case where the temperature of the ejection head of liquid becomes sufficiently close to an environment temperature. The temperature of a print head 1 is detected by a diode sensor 17 and the environment temperature is detected by a thermistor 10. Based on a change in the detected temperature of the diode sensor 17 at the time of filling of ink for the print head 1, the detected temperature of the diode sensor 17 in a case where the temperature of the print head 1 becomes close to the environment temperature is estimated as an estimated detected temperature. Based on a difference between the estimated detected temperature and the environment temperature, a correction value of the detected temperature of the diode sensor 17 is set.