Liquid ejector cleaning method and liquid ejector
AssigneeSeiko Epson Corporation
InventorMitsutaka Iwasaki
Life of this patent
Estimating the term…
Abstract
Recording head of a printer is sealed by a cap connected with a gear pump. Fluid is discharged from a nozzle through the cap by a negative pressure being generated by the gear pump. The gear pump is driven at a first rotational speed to suck the fluid in the cap and to discharge the fluid from the nozzle. Subsequently, the gear pump is driven at a second rotational speed lower than the first rotational speed and then it is stopped. This prevents backflow of the fluid to a liquid ejection head and breakage of a liquid meniscus in the nozzle of the liquid ejection head occurring when cleaning of the liquid ejection head is ended.
Claims20
A method for cleaning a liquid ejector including a liquid ejection head for ejecting liquid from a nozzle, the method comprising:
- sealing the liquid ejection head with a cap device;
- generating negative pressure with a gear pump connected to the cap device, and discharging fluid from the liquid ejection head with the negative pressure;
- suctioning fluid from the cap device with the gear pump so that a suction amount of the fluid per unit time becomes equal to a first suction amount in order to discharge fluid from the nozzle;
- and
- continuously following said suctioning, suctioning fluid from the cap device by changing the suction amount of the fluid per unit time from the first suction amount to a smaller second suction amount.
A liquid ejector comprising:
- a liquid ejection head including a nozzle for ejecting a liquid;
- a cap device for sealing the liquid ejection head;
- a gear pump, connected to the cap device, for generating negative pressure and discharging fluid out of the liquid ejection head with the negative pressure in a state in which the cap device seals the liquid ejection head, wherein the liquid ejector:
- suctions fluid from the cap device with the gear pump so that a suction amount of the fluid per unit time becomes equal to a first suction amount in order to discharge fluid from the nozzle;
- and
- continuously afterwards, suctions fluid from the cap means device by changing the suction amount of the fluid per unit time from the first suction amount to a smaller second suction amount.
A method for cleaning a liquid ejector including a liquid ejection head for ejecting liquid from a nozzle, the method comprising:
- sealing the liquid ejection head with a cap means device;
- generating negative pressure with a gear pump connected to the cap means device and suctioning fluid from the cap means device in a first suction amount per unit time with the negative pressure;
- determining whether or not fluid has been discharged from the nozzle;
- and
- changing the suction amount per unit time from the first suction amount to a smaller second suction amount when determining that fluid has been discharged from the nozzle.
The liquid ejector according to 9, further comprising:
- a flow passage for guiding liquid to the nozzle;
- and
- a valve device arranged upstream from the nozzle in the flow passage;
- wherein the valve device includes a pressure chamber, for storing liquid, and a flexible member, displaced in accordance with a pressure difference between an interior and exterior of the pressure chamber, and the valve device opens and closes based on the displacement of the flexible member.
Dependencies are inferred from the claim text.