Incremental printing of symbolic information – Ink jet – Ejector mechanism
Patent
1991-09-09
1996-10-01
Brase, Sandra L.
Incremental printing of symbolic information
Ink jet
Ejector mechanism
347 73, B41J 2085
Patent
active
055614523
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
In one form of continous multi-jet ink jet printer, the ink jets, as they break up into coplanar trains of droplets, are passed adjacent to respective electrodes, in a face of a charging electrode. Each electrode is connected to a respective lead so that appropriate charging potentials can be provided in accordance with the charging programme to the individual jets.
In view of the small dimensions involved, there being typically four or more jets per millimeter, it is very difficult to provide charging electrodes of sufficient accuracy and properly connected to their respective leads but insulated from one another.
Such electrodes and leads have previously been prepared by expensive and tedious photoresist and etching techniques, but these have not been entirely successful in providing clearly defined edges to the very narrow and narrowly spaced electrodes and leads.
SUMMARY OF THE INVENTION
In accordance with a first apsect of the present invention, a method of forming a charging electrode assembly for a continous multi-jet ink jet printer, the electrode assembly including a substrate plate of electrically insulating material provided with a series of parallel electrodes extending across an edge of the plate and a series of parallel strip leads extending across a face of the plate, each lead being aligned with and terminating at a respective one of the electrodes; comprises providing a layer of metal plating over at least the edge and the face of the plate, and removing portions of the plating material to leave the electrodes and leads, the boundary edges of the electrodes and leads being delimited by removing the plating portions so as to leave, at each boundary edge, the plating only on one of two surface portions of the substrate material which surface portions intersect at a corner edge of the substrate material formed by the intersection of the edge or face of the plate with a side of a respective one of a series of grooves cut in and across the edge and face of the plate parallel to the electrodes and leads.
The grooves may be cut before or after the plating. Thus in one application of the invention, the series of parallel grooves are cut in and across the face of the substrate plate, at least the edge and face of which are then metal plated. The edge and face are then ground to remove the metal plating from the edge and face, except in the grooves in which the electrodes and leads are formed by the residual metal plating.
If the electrode assembly is of comb-shaped kind, in which the jets pass through respective notches defined between adjacent pairs of teeth of the comb, the series of slots in the plate edge will be a series of notches which will be lined with the metal plating, the grinding removing excess metal from the exposed edges of the comb teeth between the notches.
In an alternative application of the invention, the grooves may be cut after the edge and face of the substrate plate have been provided with a layer of metal plating. The grooves will then be deep enough to cut through the layer of metal plating and extend slightly into the substrate material, leaving the electrodes and leads in the lands between the grooves. Indeed, it would be possible to combine the two alternative techniques and to produce the electrodes in pregrooved portions of the plate edge and the leads between post grooved portions of the plate face, or vice versa.
In all cases, however, the grooves can be cut very accurately in the plate, which may be made of a ceramic material, so that the electrode assembly can be prepared comparatively simply with a good guarantee that the edges of the electrodes and leads will be clearly defined with small tolerances.
The opposite face of the plate may also be provided with a layer of metal plating, in which case at least that metal plating on that face is ground off so that it is spaced from the metal of the electrodes, the remaining metal layer on that face being useful for earthing purposes.
It is important that the ink jets are aligned absolut
REFERENCES:
patent: 4194211 (1980-03-01), Hoffman et al.
patent: 4223321 (1980-09-01), Kenworthy
patent: 4324117 (1982-04-01), Schwob et al.
patent: 4347522 (1982-08-01), Bahl et al.
patent: 4378631 (1983-04-01), Head et al.
patent: 4419674 (1983-12-01), Bahl et al.
patent: 4560991 (1985-12-01), Schutrum
Brase Sandra L.
Videojet Systems International Inc.
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