The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 27, 1995
Filed:
Oct. 29, 1993
John M Wade, Poway, CA (US);
Brian P Canfield, San Diego, CA (US);
Kurt K Andersen, Manchester, MO (US);
Hanno Ix, Escondido, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. Warming voltage pulses are applied to the printhead to warm the printhead to a temperature that is at least as high as a temperature that would be produced pursuant to ink firing pulses of a predetermined voltage, a predetermined pulse width, and a predetermined pulse frequency. A continuous series of ink firing pulses are then applied to the printhead, starting with a pulse energy substantially equal to the predetermined reference pulse energy and a pulse frequency equal to the predetermined pulse frequency, and then incrementally decreasing the pulse energy of the ink firing pulses. The temperature of the printhead is repeatedly sampled while the ink firing pulses are applied to the ink firing resistors to produce a set of temperature samples respectively associated with the decreasing pulse energies. A thermal turn on energy is determined from the temperature samples, and the printhead is operated at a pulse energy that is greater than the thermal turn on energy and in a range that provides a desired print quality while avoiding premature failure of the heater resistors.