Hp Indigo B.v.

Hewlett-packard Development Company, L.p.

Hewlett-packard Indigo B.v.

Dmitry Maister

Michel Assenheimer

Sasi Moalem

Seongsik Chang

Liran Fanny Haim

Dekel Green

Kobi Shkuri

Yoav Nachmias

Yossi Cohen

Amir Ofir

Orly Cohen

Roni Yehuda

A printing device having a heating apparatus arranged to heat an image substrate, a temperature sensor associated with the image substrate, and a processor communicatively coupled to the heating apparatus. During a simulation mode of the printing device, the processor determines the heating power of the heating apparatus, predicts a temperature of the image substrate based on the heating power, compares the predicted temperature to a measured temperature of the image substrate by the temperature sensor, determines a calibration offset when the measured temperature deviates from the predicted temperature, and selectively generates a control signal for use in calibrating the temperature sensor based on the calibration offset.

Calibration of a temperature sensor of a printing device

A printing device containing a heating apparatus that heats an image substrate, a temperature sensor associated with the image substrate and a processor communicatively coupled to the heating apparatus. The processor determines the heating power of the heating apparatus, compares the heating power to a predetermined power range, determines a status of the temperature sensor when the heating power is outside the predetermined power range, and triggers a response mode of the printing device based on the determined status of the temperature sensor.

Status of a temperature sensor of a printing device

A photoconductive layer in an image forming apparatus is refreshed. A first refreshing cycle is performed, including applying, at a first refresh unit, a first refresh voltage to the photoconductive layer and applying, at a second refresh unit, a second refresh voltage to the photoconductive layer. A second refreshing cycle is performed, including applying, at the first refresh unit, a third refresh voltage to the photoconductive layer, the third refresh voltage being higher than the first refresh voltage and higher than the second refresh voltage. Each of the first and second refreshing cycles electrically bias the photoconductive layer to a refresh polarity opposite to a print polarity applied during a print routine of the image forming apparatus.

Photoconductor refreshing cycles

In one example of the disclosure, it is determined that an amount of print agent remaining in a print agent container of a print apparatus is below a threshold level. An amount of print solution is transferred from a print solution reservoir of the print apparatus, or an amount of print solution solvent is transferred from a solvent reservoir of the print apparatus, into the print agent container. At least some of the remaining print agent is caused to dissolve into the amount of print solution or print solution solvent to forma rinse solution. The rinse solution is transferred from the print agent reservoir to the print solution reservoir.

Transferring print agent in print apparatus

Examples of refreshing a photoconductive layer in an image forming apparatus are described. In one example, a method includes performing a first refreshing cycle comprising applying, at a first refresh unit, a first refresh voltage to the photoconductive layer and applying, at a second refresh unit, a second refresh voltage to the photoconductive layer. A second refreshing cycle is performed including applying, at the first refresh unit, a third refresh voltage to the photoconductive layer, the third refresh voltage being higher than the first refresh voltage and higher than the second refresh voltage. Each of the first and second refreshing cycles electrically bias the photoconductive layer to a refresh polarity opposite to a print polarity applied during a print routine of the image forming apparatus.

In one example, an electrostatic printer includes: a photoconductor member; a charging unit to charge the photoconductor member to a charged voltage; an imaging unit to generate a latent electrostatic image on the photoconductor member by discharging areas of the charged photoconductor member; a developer unit to develop a toner image on the photoconductor member using a developer voltage; and a controller to change the developer voltage and to change the charged voltage dependent on the change of the developer voltage to keep the difference between the developer voltage and the charged voltage constant.

Electrostatic printing system with charged voltage dependent on developer voltage

In one implementation, an image forming apparatus may include a photoconductive unit and a refresh unit. The photoconductive unit may include a photoconductive layer. The photoconductive layer may have a first polarity during a print routine. The refresh unit may apply a voltage to the photoconductive layer to electrically bias the photoconductive layer to have a second polarity during a refresh routine.

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Ness Ziona, Israel

Dmitry Maister