Hewlett-packard Development Company, L.p.

Hewlett-packard Development, L.p.

Daniel James Magnusson

Robert M Yraceburu

Duane A Koehler

Timothy Jacob Luedeman

Bruce A Axten

Brooke Hoyer

Francisco Alcazar

Alan Shibata

Allan G Olson

Kieran B Kelly

Kris M English

Jody L Clayburn

Stuart A Scofield

Devin Scott Uehling

Robert D Davis

Douglas Harriman

Kenneth B Wade

Jafar N Jefferson

Ian Patrick Anderson

Lorraine T Golob

Saurabh Shripad Bhide

Benjamin Whitney Griffith

Mike Burton

Joseph C O'Banion

R Scott Smith

Kenneth Blaine Wade

Stuart Scofield

According to examples, an apparatus may include a processor that may identify a first period for a heated system, the first period including a first set of power events and a first zero power event for the heated system and may identify a second period for the heated system, the second period including a second set of power events and a second zero power event for the heated system. The processor may also borrow, from the second period, a portion of a second power event of the second set of power events and may apply the borrowed portion of the second power event to a first power event of the first set of power events during the first period to remove the first zero power event from the first period.

Reduce zero power events of a heated system

In some examples, a system can include: a heating device, a Proportional Integral Derivative (PID) controller and a switching mechanism to selectively enable transmission of signals to the heating device based on a real time temperature in proximity to the heating device, wherein the PID controller is to continuously output pulse width modulation (PWM) signals independent of selective transmission of signals by the switching mechanism.

Signals controllers

In some examples, a system is disclosed that includes a roller assembly for a printer. The roller assembly includes a pressure roller, a belt coupled, a drive assembly to rotate the pressure roller and to urge the pressure roller into the belt, a heater to apply heat to the belt, and a temperature sensor to detect a temperature of the belt. In addition, the roller assembly includes a controller to increase a pressure applied to the pressure roller from a first to a second pressure in pressure in response to a temperature of the belt being greater than or equal to a first temperature threshold. Also, the controller is to initiate an advance of a print media to contact the belt in response to the temperature of the belt being greater than or equal to a second, higher temperature threshold.

Heated pressure roller assemblies for printers

Power allocation in printing devices is disclosed. Independent load requests are received from printing device heater systems. A first load request is received from a first heater system and a second load request is received from a second heater system. Power grants are allocated based on a general power arbitration of a power source in response to the independent load requests. The power grants include a first power grant based on the first load request and a second power grant based on the second load request. The power grants are adjusted based on a contextual printing condition. The power grants are adjusted to apportion a measure of the second power grant to the first power grant rather than provide the measure of the second power grant to the second heater system if a print substance density is outside a selected print substance density threshold.

Power allocation in printing devices

According to examples, a heated system may include a heat generating device, a temperature sensor to detect temperature in the heated system, and a controller. The controller may store temperatures detected by the temperature sensor over time and based on a determination that the temperature in the heated system has reached a predefined temperature value, stop application of power to the heat generating device. The controller may also calculate a rate of change of the stored temperatures corresponding to a predefined period of time prior to the application of power to the heat generating device being stopped, may determine a seeding value for a control mechanism of the heat generating device based on the calculated rate of change, and based on aa determination that a predefined condition has occurred, control the control mechanism to apply power to the heat generating device beginning with the determined seeding value.

Control of a heated system temperature

Power allocation in printing devices is disclosed. Independent load requests are received from printing device heater systems. Power grants are allocated based on a general power arbitration of a power source in response to the independent load requests. A power grant is adjusted based on a contextual printing condition to provide an adjusted grant from the power source to a printing device heater system of the printing device heater systems.

Power allocation in printing devices is disclosed. Independent load requests are received from printing device heater systems including an independent load request is received from a printing device heater system of the printing device heater systems. A power allowance of an amount of a power output is allocated to the printing device heater system if a print substance density is outside a print substance density threshold and the independent load request is outside a load threshold.

Power allocation in printing devices is disclosed. A first load request is received from a first heater system having a first thermal time constant and a second load request is received from a second heater system having a second thermal time constant. Power grants are allocated based on a general power arbitration of a power source in response to the independent load requests. The power grants include a first power grant based on the first load request and a second power grant based on the second load request. The power grants are adjusted to apportion a measure of the first power grant to the second power grant rather than provide the measure of the first power grant to the first heater system if a print substance density is within a selected print substance density threshold and the first load request is within a selected load threshold.

Power allocation in printing devices is disclosed. Independent load requests are received from printing device heater systems. Power grants are allocated based on a general power arbitration of a power source in response to the independent load requests. A power grant is adjusted based on a contextual printing condition to provide an adjusted grant from the power source to a printing device heater system of the printing device heater systems. The adjusted grant is based on a power grant limit corresponding with the contextual printing condition.

A sequence of loads within a system is determined during each of multiple time windows based on a determination of each load's temperature to a target value. The sequencing of the loads involves a determination as to whether the length of each time window is long enough to permit all of the loads to be sequentially activated in order to have their temperatures approximate the corresponding target temperatures. In some cases, the sequence of the loads is determined to be one that results in a monotonically changing power profile.

Sequencing of loads using temperature

In some examples, velocity and torque based media motor control may include ascertaining a velocity and torque for a feed roller motor associated with a feed roller, and ascertaining a velocity and torque for a drive roller motor associated with a drive roller that is to receive media from the feed roller. Further, velocity and torque based media motor control may include determining whether the torque for the drive roller motor is greater than a torque target. In response to a determination that the torque for the drive roller motor is greater than the torque target, the torque for the drive roller motor may be reduced to the torque target, and the torque for the drive roller motor may be maintained at the torque target.

Velocity and torque based media motor control

According to an example, a printing system may include printing components, an input voltage engine to determine whether an input voltage level is outside of a predetermined voltage level range, and a printing components engine to control the printing components to operate in one of a normal mode and a reduced throughput mode based upon whether the accessed input voltage level is outside of the predetermined voltage level range.

Printing system reduced throughput mode

In one example, a method for controlling temperature of a print dryer. High power is applied to a heater of the print dryer. A series of temperatures of the print dryer are periodically measured and stored until a target temperature for the print dryer is exceeded. Low power is applied to the heater after the target temperature is exceeded. A rate of temperature change at a time when the target temperature was exceeded is calculated from the stored temperatures. Using the rate, an initial heater duty cycle defining an initial heater power determined. PID control of the heater power is performed, beginning with the initial heater duty cycle, to maintain the print dryer temperature at the target temperature within a predefined accuracy.

Print dryer heater control

A method and apparatus for adjusting the print area by positioning a sheet in an imaging device utilizing length data from a prior sheet. A first sheet length is measured and thereafter utilized to determine the print zone for a subsequent sheet.

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Vancouver, WA, United States of America

Daniel James Magnusson