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AssigneeSilverbrook Research Pty Ltd
InventorsKia Silverbrook, Angus John North, Gregory John McAvoy
Estimating the term…
An inkjet printhead that has an elongate chassis, first groups of apertures spaced along the elongate chassis, an ink distribution unit defining a plurality of ink distribution passages and second groups of apertures in fluid communication with respective ink distribution passages, the ink distribution unit being mounted to the elongate chassis so that the first group of apertures and the second group of apertures coincide and, a plurality of printhead modules for ejecting ink supplied through the ink distribution passages and the aligned first and second groups.
An inkjet printhead comprising:
Dependencies are inferred from the claim text.
From the US filing history. Foreign family members aren’t listed.
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Structure thereof only for on-demand ink jet heads: structure of ink jet print heads with thermal bend detached actuators
Control methods or devices therefor, e.g. driver circuits, control circuits: reducing costs
Control methods or devices therefor, e.g. driver circuits, control circuits: reducing demand in current or voltage
Control methods or devices therefor, e.g. driver circuits, control circuits: detecting current
Term ended 23 Nov 2022 (estimated)
The present invention relates to a thermal ink jet printhead, to a printer system incorporating such a printhead, and to a method of ejecting a liquid drop (such as an ink drop) using such a printhead.
The present invention involves the ejection of ink drops by way of forming gas or vapor bubbles in a bubble forming liquid. This principle is generally described in U.S. Pat. No. 3,747,120 (Stemme).
There are various known types of thermal ink jet (bubblejet) printhead devices. Two typical devices of this type, one made by Hewlett Packard and the other by Canon, have ink ejection nozzles and chambers for storing ink adjacent the nozzles. Each chamber is covered by a so-called nozzle plate, which is a separately fabricated item and which is mechanically secured to the walls of the chamber. In certain prior art devices, the top plate is made of Kapton™ which is a Dupont trade name for a polyimide film, which has been laser-drilled to form the nozzles. These devices also include heater elements in thermal contact with ink that is disposed adjacent the nozzles, for heating the ink thereby forming gas bubbles in the ink. The gas bubbles generate pressures in the ink causing ink drops to be ejected through the nozzles.
Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying representations. The drawings are described as follows.
FIG. 1 is a schematic cross-sectional view through an ink chamber of a unit cell of a printhead according to an embodiment of the invention, at a particular stage of operation.
FIG. 2 is a schematic cross-sectional view through the ink chamber FIG. 1, at another stage of operation.
In the description than follows, corresponding reference numerals, or corresponding prefixes of reference numerals (i.e. the parts of the reference numerals appearing before a point mark) which are used in different figures relate to corresponding parts. Where there are corresponding prefixes and differing suffixes to the reference numerals, these indicate different specific embodiments of corresponding parts.
Overview of the Invention and General Discussion of Operation
With reference to FIGS. 1 to 4, the unit cell 1 of a printhead according to an embodiment of the invention comprises a nozzle plate 2 with nozzles 3 therein, the nozzles having nozzle rims 4, and apertures 5 extending through the nozzle plate. The nozzle plate 2 is plasma etched from a silicon nitride structure which is deposited, by way of chemical vapor deposition (CVD), over a sacrificial material which is subsequently etched.