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:
Aug. 05, 1997
Filed:
May. 22, 1996
Mark Hirst, Boise, ID (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A system of the present invention includes an ambient condition sensor for estimating the consumption of toner, developer, or similar printing supply in an electrostatic or ink jet printer. In a preferred embodiment, the ambient condition being monitored is relative humidity, though in other embodiments other indicators of ambient air conductivity or break down voltage are measured. Consumption is estimated by classifying each pixel to be printed according to the number of neighbors of that pixel, accumulating a sum according to each classification, multiplying each accumulated sum by a weight that accounts for its classification, and calculating an overall sum of the weighted products. The overall sum is then scaled by a factor that accounts for the conductivity of ambient air as measured by the sensor to provide an incremental estimate of consumption. The scaling factor is determined by empirical studies. A warning such as 'low toner' is displayed on the printing device and on a remote console when the integrated incremental estimates of consumption surpass a limit.