Hewlett-packard Company

Other

Hewlett-packard Development Company, L.p.

Ronald A Juve

Jason M Quintana

James M Brenner

Algird M Gudaitis

Rick Minoru Tanaka

Robert R Hay

Matias Negatu

George S Kaufman

Diane M Dancer

An embodiment of a printing system is provided with an inkjet printhead having plural portions each having an ink-ejecting nozzle. The printing system includes plural heater elements each associated with one of the plural portions to pre-warm ink dispensed by the nozzle of the associated portion in response to a pre-warming signal. The printing system also includes a controller configured to generate the pre-warming signal for one or more heater elements based on a selection criteria for generating the pre-warming signal only when the nozzle of said associated portion is required to eject ink during an upcoming print swath.

Pre-warming portions of an inkjet printhead

A method of an embodiment of the invention is disclosed that determines the average power utilization for inkjet printing a print swath. In response to determining that the average power utilization exceeds a threshold, an average power reduction action is performed.

Performing power reduction action when average power utilization for inkjet printing a swath exceeds a threshold

Optical encoder system and method for use in printing devices

A circuit and method for improving the reliability of ink jet printers in the presence of ink shorts is provided. Ground and supply voltage contacts at the electrical interconnect to the ink pens are separated by at least one electrical contact that connects a higher impedance circuit such as a data line to provide warning of the ink short in order to take corrective action before any damage to the printer occurs. Resistive isolation between each of the data lines allows the data signals to continue to reach the other pens in the presence of an ink short. After the ink short has been detected and an alarm signal generated, adaptive re-mapping of the data to utilize the remaining good pens and data lines to maximum advantage which allows the printer to continue printing. The data for the affected pen could be adaptively remapped to the remaining good pens to provide continued printing. The data can also be adaptively re-mapped to remaining good data lines to also provide for continued printing.

Method for improving ink jet printer reliability in the presence of ink

One embodiment of this invention has an electronic circuit which is configured to count the elapsed time in minutes since the initiation of a nursing session. The elapsed time is indicated on a visual display (23) which also includes a right/left breast subdisplay (23d) for indicating the breast from which the baby last fed, which is also the breast to be used when the baby starts feeding again. Breast feeding timer (10) includes a reference clock (11), a clock counter (14), an alarm counter (16), a three digit digital display (23), including a separate right/left subdisplay (23d), an audible alarm (26), and plurality of switches for controlling and initiating stop, start, reset, alarm program, and right/left selection display functions.

Breast feeding timer

An audio compression circuit for limiting an audio television signal in a linear fashion at a pre-established maximum level is disclosed. The circuit includes a series resistance circuit for establishing a predetermined resistance on an amplifier to establish a supply voltage through a detection and level adjustment circuit. The detection and level adjustment circuit increases the supply voltage to a relatively higher reference voltage, which is shifted through a level adjustment circuit to a control voltage, which control voltage is greater than a threshold voltage of a field effect transistor. The field effect transistor is a significant aspect of a shunt circuit connected in parallel to the detection and level adjustment circuit. The shunt circuit acts in response to the control voltage to vary the resistance across the drain and source of the field effect transistor to prevent the outlet voltage to a loudspeaker from exceeding a predetermined level established by the level adjustment circuit.

Audio compression circuit for television audio signals

An electrostatic voltmeter for measuring the electrostatic potential on a photosensitive drum has a detector capacitively coupled to the drum for providing an output signal in response to the potential on the drum. An AC voltage source is coupled in circuit with the drum and the detector for applying an AC signal across the surface-to-detector capacitance. Circuitry coupled to the detector determines the detector gain in response to the value of the AC component of the output signal and the value of the applied AC signal. The product of the reciprocal of the detector gain and the value of the DC component of the output signal is representative of the electrostatic potential on the surface.

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Brush Prairie, WA, United States of America

Ronald A Juve