Incremental printing of symbolic information – Ink jet – Ejector mechanism
Reexamination Certificate
1999-03-04
2001-02-06
Nguyen, Thinh (Department: 2861)
Incremental printing of symbolic information
Ink jet
Ejector mechanism
C347S005000
Reexamination Certificate
active
06183063
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to ink jet printers and, in particular, to a printer cartridge orientation which is suitable for increased printing speeds and improved print quality.
BACKGROUND OF THE INVENTION
Ink jet printers comprise two basic types, namely, printers having movable printheads which traverse the print media and deposit ink droplets in a defined pattern on each swath of the printer cartridge and printers having substantially fixed page wide printheads which contain an array of nozzles along the length of the printhead.
In a moveable printhead design, one or more printer cartridges each containing a printhead are attached to a movable carriage which traverses the print media as the media moves transverse to the carriage movement through the printer. Use of multiple printer cartridges rather than a single cartridge attached to a movable carriage greatly increases print speed. However, in order to obtain the highest quality printing, alignment between the print cartridges is critical and is often difficult to maintain over the life of the printer. As the print cartridges are changed, slight misalignment of the cartridges occurs thereby degrading the print quality. The alignment problems associated with multiple printer cartridges are not present when using a single print cartridge, however, a single cartridge printer cannot print at the higher speeds obtainable by use of multiple printer cartridges.
In an effort to increase printer speed without sacrificing print quality, page wide printhead arrays having a length equal to, or slightly less, than the width of print media have been developed. The page wide printhead arrays are set at about 90 degrees or substantially perpendicular to the direction of travel of print media through the printer. Such large or page wide printhead arrays greatly increase the printing speeds but require a higher density of nozzles on the printhead in order to obtain the same print quality obtained by the use of a movable printhead. Moveable printheads do not suffer from lower print quality for printheads having the same nozzle density as the page wide printheads because such printheads can be moved across the print media to create a higher density of ink droplets on the media.
One disadvantage of a page wide printhead array is the difficulty associated with manufacturing such a printhead with a sufficiently high density of nozzles sufficient to produce the desired print quality. Providing a high density of nozzles on the printhead is complicated by the routing requirements for the electrical tracing to the ink ejection devices and for the ink channels and flow features on the printheads for flow of ink to the nozzle chambers adjacent each nozzle.
Another disadvantage of page wide printheads oriented perpendicular to the direction of travel of the print media is that such printheads consume excessive amounts of power because all or a significantly large percentage of the nozzles of the printhead must operate simultaneously to provide full ink coverage on the print media, such as for a fully printed page.
An object of the invention is therefore to provide an improved high speed, high quality printer.
Another object of the invention is to provide a printer having an improved page wide printhead array.
A further object of the invention is to provide a printer which improves print quality without sacrificing print speed.
Still another object of the invention is to reduce the power consumption of a page wide printhead device.
Another object of the invention is to reduce the manufacturing costs and difficulties associated with producing page wide printhead arrays.
SUMMARY OF THE INVENTION
With regard to the above and other objects, the invention provides an ink jet printer including a print media movement device for moving a print media having a printed width through the printer along a print media path and a printhead cartridge attached to the printer at an angle between 0° and 90° relative to an axis perpendicular to an axis along the direction of the media path through the printer, the cartridge having a length sufficient to print substantially the entire width of the printed width across the print media wherein the cartridge contains one or more printheads along at least a portion of the length thereof, each printhead having one or more nozzle arrays.
In another aspect the invention provides a method for printing which comprises providing a printer containing a media carriage, a print media disposed in the carriage and an elongate cartridge removably attached to the printer and disposed across the carriage at an acute angle relative to an axis perpendicular to a direction of movement of the print media through the printer, wherein the cartridge contains a plurality of printheads along at least a portion of the length thereof, each printhead containing at least one nozzle array and energizing ink imparting devices on the printhead to effect ejection of ink from the printhead in a pattern sufficient to produce indicia on the print media.
For the purposes of this invention, the “angle” means the smallest angle made by an axis along the length of the printhead relative to an axis perpendicular to path of the print media through the printer.
An advantage of the printer according to the invention is that ink droplets forming the printed indicia may be ejected from only a portion of the cartridge at a time, thereby significantly reducing power consumption yet producing a fully printed media. In a conventional printer, the page wide cartridge is disposed at an angle so that the cartridge lies substantially perpendicular to an axis along the direction of movement of the print media through the printer. Accordingly, in order to print an entire line of indicia across the print media at one time, a substantial number of nozzles along the length of the printhead must be activated or fired at the same time. Another advantage is that the angled printhead of the invention need not contain as high a density of nozzles as a similar printhead disposed perpendicular to the paper path in order to provide the same print quality.
Alternatively, the manufacturing costs for printers may be significantly reduced because the invention enables construction of a printhead having increased nozzle-to-nozzle spacing along the printhead without sacrificing print resolution. Because the invention enables production of high resolution printheads with increased nozzle spacing, it is easier and less costly to manufacture the printhead as compared to conventional printheads which are mounted substantially perpendicular to the paper path.
REFERENCES:
patent: 4612554 (1986-09-01), Poleshuk
patent: 5160945 (1992-11-01), Drake
patent: 5192959 (1993-03-01), Drake et al.
patent: 5365645 (1994-11-01), Walker et al.
patent: 5440332 (1995-08-01), Good
patent: 5568169 (1996-10-01), Dudek et al.
patent: 5619622 (1997-04-01), Audi et al.
patent: 5638108 (1997-06-01), Nacman et al.
Bolash John Philip
Campbell Michael Clark
Eade Thomas Jon
Lexmark International Inc.
Luedeka Neely & Graham
Nguyen Thinh
Sanderson Michael T.
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