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US 11,235,582 B2Granted
Detecting ink states for printers based on monitored differential pressures
AssigneeHewlett-Packard Development Company, L.P.
InventorsMatthew J. Janssen, James R. Cole, James W. Ring
Life of this patent
Estimating the term…
Abstract
A technique includes coupling outlets of a first ink supply and a second ink supply together to provide ink to a printhead of a printer; and pressurizing the first ink supply and the second ink supply with air so that an air pressure of the first ink supply has a different air pressure than an air pressure of the second ink supply. The technique includes monitoring an ink-to-air differential pressure of the first ink supply or the second ink supply; and detecting an ink state for the printer based on the monitored ink-to-air differential pressure.
Claims14
A method comprising:
- coupling outlets of a first ink supply and a second ink supply together to provide ink to a printhead of a printer;
- pressurizing the first ink supply and the second ink supply with air so that an air pressure of the first ink supply has a different air pressure than an air pressure of the second ink supply;
- monitoring an ink-to-air differential pressure of the first ink supply or the second ink supply;
- and
- detecting an out of ink state for the printer based on the monitored ink-to-air differential pressure, wherein detecting the out of ink state comprises:
- determining a rate at which the ink-to-air differential pressure changes with respect to a volume of ink delivered to the printhead;
- and
- detecting the out of ink state based on the rate at which the ink-to-air differential pressure changes.
5 more elements
An apparatus comprising:
- a print cartridge;
- a primary ink supply to provide ink for the print cartridge at an ink outlet of the primary ink supply, the primary ink supply having an associated first air pressure;
- an auxiliary ink supply to provide ink for the print cartridge at an ink outlet of the auxiliary ink supply, the auxiliary ink supply having an associated second air pressure different than the first air pressure;
- a sensor to sense a differential between the first air pressure and an ink pressure associated with the primary ink supply;
- and
- a controller to detect a state of the primary ink supply based on the sensed differential representing a pressure change from an ink-to-air pressure associated with a full ink level for the primary ink supply near or at a predefined pressure difference between the first air pressure and the second air pressure.
3 more elements
An apparatus comprising:
- a printhead;
- a first ink reservoir to provide ink for the printhead at an ink outlet of the first ink reservoir, the first ink reservoir having an associated first air pressure;
- a second ink reservoir to provide ink for the printhead at an ink outlet of the second ink reservoir, the second ink reservoir having an associated second air pressure different than the first air pressure;
- a sensor to sense a differential between the second air pressure and ink pressure associated with the second ink reservoir;
- and
- a controller to detect an ink state for the first ink reservoir based on the sensed differential.
3 more elements
A method comprising:
- coupling outlets of a first ink supply and a second ink supply together to provide ink to a printhead of a printer;
- pressurizing the first ink supply and the second ink supply with air so that an air pressure of the first ink supply has a different air pressure than an air pressure of the second ink supply;
- monitoring an ink-to-air differential pressure associated with the first ink supply;
- and
- detecting an out of ink state of the first ink supply based on the monitored ink-to-air differential pressure, wherein detecting the out of ink state of the first ink supply comprises detecting whether the differential pressure associated with the first ink supply increases by the pressure difference between the air pressure of the first ink supply and the air pressure of the second ink supply.
2 more elements
An apparatus comprising:
- a print cartridge;
- a primary ink supply to provide ink for the print cartridge at an ink outlet of the primary ink supply, the primary ink supply having an associated first air pressure;
- an auxiliary ink supply to provide ink for the print cartridge at an ink outlet of the auxiliary ink supply, the auxiliary ink supply having an associated second air pressure different than the first air pressure;
- a sensor to sense a differential between the first air pressure and an ink pressure associated with the primary ink supply;
- and
- a controller to detect a state of the primary ink supply based on the sensed differential, wherein the controller to:
- determine a rate of transition of the sensed differential versus a volume of delivered ink based on the sensed differential;
- determine whether the rate exceeds a predetermined threshold;
- and
- detect an out of ink state for the primary ink supply based on a result of the determination.
7 more elements
Dependencies are inferred from the claim text.