Inkdrop-volume test using heat-flow effects, for thermal-inkjet

Details Inkdrop-volume test using heat-flow effects, for thermal-inkjet Inkdrop-volume test using heat-flow effects, for thermal-inkjet

1993-11-22

1998-02-03

Fuller, Benjamin R.

Incremental printing of symbolic information

Ink jet

Controller

347 7, B41J 2195

Patent

active

057149895

ABSTRACT:
The invention provides methods of determining ink volume ejected from a printhead, controlling ejected volume, and warning of low ink supply. A printhead is fired to eject ink: this operating step includes heating the ink and head; carrying away heat, in the ejected volume, from the head; and conveying a volume of cooler ink to the head, from a supply, to replace the ejected ink. The method finds the head cooling caused by the carrying-away and conveying; and to this applies a known calibration to find the volume ejected. The heating is roughly equal to that which occurs in printing. Besides the operating step, the method preferably includes finding (a) printhead cooling due to static mechanical thermal drain alone, and (b) printhead thermal response to warming by the same amount of heat as used to fire the pen in the operating step--but without ink ejection. These baseline values are used with the cooling observed in the operating step to isolate the effect of ink ejection and so find the cooling more accurately. The warming can be done by applying electrical energy to printhead-firing resistors, at pulse widths narrower than used for firing--but greater frequency--to inject power equal to that in normal operation. The temperature measurements are made by monitoring a conventional sensing resistor in the pen, and can include fitting a linear slope to the observed temperature-vs.-time relation.

REFERENCES:
patent: 4982199 (1991-01-01), Dunn
patent: 5206668 (1993-04-01), Lo et al.

Affiliated with

Also associated with

Rating

Inkdrop-volume test using heat-flow effects, for thermal-inkjet does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Inkdrop-volume test using heat-flow effects, for thermal-inkjet , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inkdrop-volume test using heat-flow effects, for thermal-inkjet will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-666912