An image forming apparatus includes a printhead in which a plurality of element substrates for discharging a print material are arranged; a heating unit that maintains a temperature within the element substrate at a target temperature for each of the plurality of element substrates; a detection unit that detects the temperature within the element substrate for each of the plurality of element substrates; and a control unit that, for each of the plurality of element substrates, compares a highest temperature within the element substrate that is detected by the detection unit with a predetermined threshold, and if the highest temperature exceeds the predetermined threshold, sets the target temperature for the element substrate at a temperature which is higher than a target temperature set when the highest temperature does not exceed the predetermined threshold and lower than the predetermined threshold.

A droplet ejecting device includes: a first nozzle group consisting of N pieces of first nozzles aligned in a first direction; a second nozzle group consisting of N pieces of second nozzles aligned in the first direction and at the same positions in the first direction as the first nozzles; and a controller. The controller is configured to determine whether an ejection quantity per unit time is not smaller than a first threshold. When the ejection quantity is equal to or greater than the first threshold, a first combination of N pieces of nozzles from among the N pieces of first nozzles and the N pieces of second nozzles is selected. When the ejection quantity is smaller than the first threshold, a second combination of N pieces of nozzles from among the N pieces of first nozzles and the N pieces of second nozzles is selected.

A control circuit for a thermally-activated microfluidic ejection element and a method of dispensing a fluid composition from the same is provided. The thermally-activated microfluidic ejection element includes a plurality of nozzles and a thermal actuator associated with each nozzle, and a control circuit that includes: a logic circuit that increments through a pre-determined sequence, wherein the sequence is defined by the physical layout of the thermally-activated microfluidic ejection element; a first input in electrical communication with the logic circuit; a second input in electrical communication with each thermal actuator, wherein the first input and second input are used to select and energize each thermal actuator on the thermally-activated microfluidic ejection element.

A printing apparatus according to the present invention includes a printhead with a plurality of print elements for generating energy used for printing an image on a print medium, a first temperature detection element and a second temperature detection element at positions different in a direction of a print element array in which the plurality of print elements are arrayed. The apparatus corrects a signal concerning a head temperature based on an output from the first temperature detection element, and corrects, based on the corrected signal concerning the head temperature, a signal concerning a head temperature output from the second temperature detection element.

One embodiment of the present invention is a printing apparatus including: a print head having a printing element column in which a plurality of printing elements for ejecting ink from ejection ports is arrayed and performing printing on a printing medium by ejecting ink based on print data; a sensor that detects temperature of the print head; an acquisition unit configured to acquire information indicating a number of dots to be printed by printing elements corresponding to a predetermined area in the printing element column; and a control unit configured to control a printing operation of the print head based on temperature detected by the sensor and the number of dots acquired by the acquisition unit, and the printing apparatus performs printing on the printing medium by ejecting ink from the print head while the print head and the printing medium are moving relatively.

A fluid dispensing method, the method comprising steps of: providing a system comprising a reservoir, a micro-fluidic thermal inkjet print head in fluid communication with the reservoir, a controller and a power source in electrical communication with the controller and the print head, the reservoir containing a fluid, the micro-fluidic thermal inkjet print head comprising nozzles; heating the fluid in the microfluidic device to a temperature of about 40 C to 75 C in less than about 1000 ms; activating the print head to fire the nozzles about 200 fires/nozzle at a first frequency; subsequent to step c, activating the print head to fire the nozzles at a second frequency, the second frequency substantially less than the first frequency; and subsequent to step d, activating the print head to fire the nozzles at a third frequency substantially greater than the first frequency.

An apparatus that transfers data to a recording head having a plurality of recording elements includes a transfer unit for transferring recording data to which a series of commands is attached in synchronization with a clock. The series of commands includes a stop command for temporarily stopping transfer of the recording data for a predetermined period in accordance with power-distribution timing of the recording elements.

A liquid ejecting head including: a first liquid ejecting portion configured to eject a liquid; a second liquid ejecting portion configured to eject a liquid; a first supply flow path configured to supply the liquid to the first liquid ejecting portion and the second liquid ejecting portion; and a temperature detection element for measuring a temperature of the liquid. The first supply flow path includes a common portion to which the liquid is supplied; a first branch portion that communicates with the common portion at a communication position, and that supplies the liquid from the common portion to the first liquid ejecting portion; and a second branch portion that communicates with the common portion at the communication position, and that supplies the liquid from the common portion to the second liquid ejecting portion. The temperature detection element is disposed at a vicinity of the communication position.

A heater includes: a planar heat generator; a power supply circuit that controls supply of power to the planar heat generator; a plurality of temperature sensors that is provided on the planar heat generator and measures a temperature; and a hardware processor that detects abnormality of the temperature sensor in a case where a difference in temperature measured by each of two of the temperature sensors out of the plurality of temperature sensors exceeds an abnormality threshold value after a predetermined waiting time has elapsed since the supply of power to the planar heat generator is stopped.

There is provided an image recording apparatus including a carriage, a head, a velocity sensor, and a controller. The controller obtains velocity data of the carriage from the velocity sensor, determines a threshold value based on the velocity data, records an image on a recording medium, and suspends a recording pass when the controller has determined that a velocity indicated by the velocity data is lower than a velocity corresponding to the threshold value. The controller can execute a first recording mode and a second recording mode in which the velocity of the carriage is faster than that of the first recording mode. The velocity data for the first recording mode is obtained in a warm-up time after a recording command is received until recording of the image is started. The velocity data for the second recording mode is obtained in other time other than the warm-up time.