Incremental printing of symbolic information – Ink jet – Fluid or fluid source handling means
Reexamination Certificate
1999-04-13
2001-05-01
Le, N. (Department: 2861)
Incremental printing of symbolic information
Ink jet
Fluid or fluid source handling means
Reexamination Certificate
active
06224198
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a method and apparatus for refilling disposable ink cartridges of ink jet printheads from ink reservoirs located off-board the printhead carriages. The pressure in ink lines connecting the off board reservoirs to the cartridges is monitored prior to and during a refill operation so that refilling is prohibited or stopped if an ink line is open to atmospheric pressure.
BACKGROUND OF THE INVENTION
To reduce printhead carriage mass so as to obtain high carriage accelerations and velocities, ink jet printers are provided with ink reservoirs located off-board the carriages, ink in these reservoirs being used to replenish ink drawn from the printhead cartridge reservoirs during printing. The refill may take place continuously or intermittently. For continuous refilling, the off-board reservoirs may be connected via hoses to the printhead cartridges as shown for example in U.S. Pat. No. 5,369,429. For intermittent refilling as shown in U.S. Pat. Nos. 5,136,305, 4,967,207 and 4,968,998, the printheads are moved to a refill station where the printhead cartridges are refilled with ink from the off-board reservoirs.
Ink leakage is a particular concern in network printers using the intermittent type refill system. Such printers are frequently left running unattended for extended periods of time and, generally speaking, have larger off-board ink reservoirs. Therefore, the potential for catastrophic ink spillage exists if a leak should occur during a period when the printer is running unattended.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a refill system for intermittently refilling a cartridge reservoir of an ink jet printer from an off-board ink supply, the system providing checks for catastrophic and slow leaks prior to initiating each refill operation.
Another object of the invention is to provide a refill system for intermittently refilling the cartridge reservoir of an ink jet printer from an off-board ink supply via an ink flow path, the refill system being characterized in that the ink flow path is monitored for leaks both before and during each refill operation.
A further object of the invention is to provide a refill system for intermittently refilling the cartridge reservoir of an ink jet printer from an off-board ink supply via an ink flow path, the system being characterized in that, after each refill operation, ink is purged from the ink flow path and the path is vented to the atmosphere.
According to the invention, a refill system for intermittently refilling the cartridge reservoir of an ink jet printer from an off-board ink supply comprises an ink flow path connected to the ink supply for dispensing ink into the cartridge reservoir; a pressure detector; an air pump; a pressure control valve for selectively connecting the ink flow path and the ink supply to the air pump; a controller responsive to the pressure detector for controlling the pump and the pressure control valve to apply air at a test pressure from the pump to the ink flow path to check for leaks in the ink flow path, and apply air at an ink feed pressure from the pump to the ink supply to feed ink from the ink supply through the ink flow path to the cartridge reservoir. A dispensing valve blocks the ink flow path during the interval the test pressure is being applied and vents the ink flow path to the atmosphere after a refill operation is completed. The control valve is a multiport valve having positions for connecting the ink flow path to the atmosphere or to the pump, and positions for applying atmospheric pressure or pressure from the pump to the off-board ink supply.
In accordance with one aspect of the invention, the air displacement required to raise the pressure in the ink flow path from atmospheric pressure to the ink flow pressure is measured and utilized as an indication of the volume of ink in the off-board ink supply prior to initiating an ink transfer.
In accordance with a further aspect of the invention, an ink level sensor is provided in the cartridge reservoir for sensing the level of ink therein. During a refill operation the controller monitors the ink level sensor to determine if the ink level is continuously rising. If the ink level is not continuously rising, the refill operation is terminated and an indicator is set. In an alternative embodiment, one of two indicators may be set depending on the saved indication of the volume of ink in the off-board ink supply prior to initiating the ink transfer.
REFERENCES:
patent: 4432005 (1984-02-01), Duffield et al.
patent: 4437104 (1984-03-01), Hudson
patent: 4558326 (1985-12-01), Kimura et al.
patent: 4610202 (1986-09-01), Ebinuma et al.
patent: 4631556 (1986-12-01), Watanabe et al.
patent: 4636814 (1987-01-01), Terasawa
patent: 4702287 (1987-10-01), Higie et al.
patent: 4967207 (1990-10-01), Ruder
patent: 4968998 (1990-11-01), Allen
patent: 5136305 (1992-08-01), Ims
patent: 5282495 (1994-02-01), Chamberlain
patent: 5369429 (1994-11-01), Erickson
patent: 5504510 (1996-04-01), Miyakawa
patent: 5944066 (1999-08-01), Viard
patent: 5-318760 (1993-12-01), None
Cook William Paul
Denton Gary Allen
Griffin, Jr. B. Franklin
Le N.
Lexmark International Inc.
Nghiem Michael
LandOfFree
Method and apparatus for refilling ink jet cartridges with... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for refilling ink jet cartridges with..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for refilling ink jet cartridges with... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2487618