Patent Application
20100171789
This application claims priority under 35 U.S.C. ยง119(a) of Korean Patent Application No. 10-2009-0000846, filed on Jan. 6, 2009, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present general inventive concept relates to a nozzle capping device of an inkjet printer that prevents a nozzle for ejecting ink droplets from being dried and clogged.
2. Description of the Related Art
In general, an inkjet printer is a printing device that prints predetermined images by ejecting ink droplets onto desired locations on a printing medium and can be classified as either a shuttle type inkjet printer or an array type inkjet printer. A shuttle type inkjet printer includes a print head including a single nozzle chip, and prints by reciprocally moving the print head along the width direction of a printing medium. An array type inkjet printer includes a plurality of nozzle chips arranged along the width direction of a printing medium, and prints line by line. Recently, printers having an array type head are preferred due to increased printing speeds.
Meanwhile, if printing jobs using an inkjet print head have not been performed for a long period of time, ink in a droplet ejection hole of a nozzle chip, i.e., a nozzle, may dry, and thus the nozzle may become clogged. In this case, droplets are not ejected from the nozzle, preventing a clear color image from being printed. Thus, an inkjet printer includes a capping device that covers the nozzle chip so as to prevent the nozzle chip from being exposed to external air while printing jobs are not being performed. The capping device surrounds and covers the nozzle chip of the inkjet print head so that ink in the nozzle does not dry and solidify due to the nozzle chip being exposed to external air, similar to a cap of an ink pen.
However, it is difficult to completely prevent ink from becoming dry by merely covering the nozzle chip. In particular, since the array type inkjet printer having the plurality of nozzles chips arranged along the width direction of a printing medium has recently been preferred, it is required to increase the size of the capping device in order to wholly cover an array type inkjet print head, which conventionally may fail to tightly seal the inkjet print head and dries the nozzle faster than expected due to a gap between the capping device and the nozzle. Thus, a capping device needs to stably prevent a nozzle from being dried even when printing jobs have not been performed for a long period of time.
The present general inventive concept provides a nozzle capping device of an inkjet printer including a cap covering a nozzle chip of an inkjet head and a humidity supply unit to supply humidity to an inner space formed by the cap covering the nozzle chip and the inkjet head.
Additional features and utilities of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept.
The humidity supply unit may include a storage unit to store a liquid and a connection tool connected to the storage unit to supply the humidity to the inner space formed by the cap and the inkjet head.
The connection tool may include a connection unit to selectively connect the inner space formed by the cap and the inkjet head and a connection hole formed in the storage unit to connect the inner space formed by the cap and the inkjet head and the storage unit.
The connection unit may include a pin valve to elastically close the connection hole, wherein, when the cap covers the nozzle chips, the pin valve is elastically pushed against by the inkjet head and thus the connection hole is opened.
The connection unit may include a slider to slidably move and close the connection hole, wherein, if the slider slidably moves, the hole is opened and thus the inner space formed by the cap and the inkjet head and the storage unit is connected to each other.
The liquid may be one selected from the group consisting of water and non-color ink.
The storage unit may be one selected from the group consisting of a case formed of a hard material, a flexible bag that expands and contracts, and a porous unit that sponges up liquid.
The storage unit may include a remnant detecting sensor to measure remaining amounts of liquid in the storage unit.
The nozzle capping device may further include a liquid supplementing unit to supplement more of the liquid into the storage unit according to a signal generated by the remnant detecting sensor.
The nozzle capping device may further include a hygrometer to measure the humidity of the inner space formed by the cap and the inkjet head.
Embodiments of the present general inventive concept further include a nozzle capping device of an image forming apparatus, including a printhead with a plurality of nozzle chips to eject ink therefrom, and a capping unit to provide continuous humidity to the plurality of nozzle chips when capping the nozzle chips.
The above and other features and advantages of the present general inventive concept will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
Reference will now be made in detail to the exemplary embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below in order to explain the present general inventive concept by referring to the figures.
Referring to
Referring to
Two pin valves 14 may be used to elastically cover the connection holes 11a and 12a and function as connection units. When the body 10 is spaced apart from the print head 20, the pin valves 14 may close the connection holes 11a and 12a. When the body 10 approaches the print head 20 to allow the cap 11 to cover the nozzle chips 21, the pin valves 14 may open the connection holes 11a and 12a.
A method of operating the nozzle capping device of the present exemplary embodiment will now be described.
When a printing job is performed, the body 10 of the nozzle capping device may be spaced apart from the print head 20 in order for nozzles of the nozzle chips 21 to normally eject ink onto a sheet (not illustrated).
In a printing standby state after the printing job is completed, the body 10 may approach the print head 20 according to the driving of the motor 30 and thus the cap 11 may surround and cover the nozzle chips 21 to form the inner space with the print head 20, preventing the nozzle chips 21 from exposure to external air. The pin valves 14 may be pressed by the print head 20, and thus the connection holes 11a and 12a closed by the packing unit 14a may be opened, as illustrated in
Therefore, the humidity of the inner space that surrounds the nozzle chips 21 can remain constant, thereby stably preventing nozzles from being dried and clogged.
Other exemplary embodiments of the nozzle capping device will now be described.
Referring to
Referring to
In the present embodiment, the storage units 12 may be cases formed of a hard material including a liquid storage space. For example, a plastic material may be used as the hard material. However, the storage units 12 may be flexible bags that flexibly expand and contract. A film material such as vinyl may be used as a material of the flexible bag. The film material may be sufficiently durable so that air or liquid does not leak. The flexible bag formed of the film material may store liquid. In addition, the storage units 12 may also be porous members containing liquid. A sponge may be used as a material of the porous member. The porous member formed of the sponge may be used as a storage unit by sponging up water or non-color ink.
Therefore, the nozzle capping devices of the above exemplary embodiments can sufficiently prevent nozzles from being clogged by continuously supplying humidity to an inkjet printer even when printing jobs have not been performed for a long period of time, thereby achieving a stable performance of the inkjet printer.
While the present general inventive concept has been particularly illustrated and described with reference to exemplary embodiments thereof, it will be understood by one of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present general inventive concept as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2009-0000846 | Jan 2009 | KR | national |
