Method and apparatus for preventing nozzle clogging in ink jet printing apparatus
AssigneeRicoh Company, Ltd.
InventorsShuzo Matsumoto, Takeo Murai, Mitsumi Fujii
Life of this patent
Estimating the term…
Abstract
An ink-jet printing apparatus and method in which a head unit having at least one nozzle ejects ink drops on demand, a sheet transporting path disposed below the head unit transports a sheet through the head unit, and an ink deposit unit disposed below the sheet transporting path is arranged to directly receive ink drops ejected form the nozzle when a nozzle-clog-preventing/ink ejection operation is executed. A controller initiates and stops the nozzle-clog-preventing/ink ejection operation based on whether or not a sheet is detected by sheet detecting elements disposed adjacent to the head unit.
Claims12
An ink jet printing apparatus comprising:
- at least one print head including a plurality of nozzles arranged to eject ink drops in response to receiving a signal;
- a sheet transporting path disposed below said at least one print head, said sheet transporting path configured and adapted to transport one or more individual sheets toward and past said at least one print head;
- an ink deposit disposed below said sheet transporting path and arranged to receive ink drops ejected from said nozzles when a nozzle clog-preventing ink ejection is executed;
- a print head and operating controller, operatively connected to said at least one print head to control said at least one print head;
- a sheet detecting device, comprising at least one of at least one pair of sheet detecting elements, operatively connected with said print head operating controller, wherein
- said sheet detecting elements are positioned adjacent to said at least one print head, and are configured and adapted to detect that a sheet having an image thereon has been ejected from below said at least one print head, to detect a new sheet that is to be transported under said at least one print head, and to communicate the presence or absence of a sheet between said at least one print head and said ink deposit to said print head operating controller, wherein
- said print head operating controller is configured and adapted to initiate said nozzle clog-preventing ink ejection by said at least one print head when said sheet detecting device detects that a sheet having an image thereon has been ejected from below said at least one print head, and to stop said nozzle clog-preventing ejection when said sheet detecting device detects that a new sheet is to be transported under said at least one print head.
A method of preventing or reducing clogging in an ink jet printer print head, the method comprising the steps of:
- positioning an ink jet printer print head over an ink deposit in an ink jet printer;
- transporting a sheet on a sheet transporting path to a print position between said print head and said ink deposit;
- printing an image on said sheet, and ejecting said sheet;
- detecting ejection of said sheet with a first sheet detecting element, and communicating said ejection of said sheet to a print head operating controller;
- initiating a nozzle clog-preventing ink ejection from said print head into said ink deposit with said print head operating controller upon communicating said ejection of said sheet to said print head operating controller;
- detecting a new sheet on said sheet transporting path with a second sheet detecting element before said sheet is transported to said print position, and communicating said detection of said sheet to said print head operating controller;
- and
- stopping said nozzle clog-preventing ink ejection from said print head into said ink deposit with said print head operating controller upon communicating said detection of said sheet to said print head operating controller.
Dependencies are inferred from the claim text.