Patent Grant
6910763
1. Field of the Invention
The invention relates generally to an ink storage unit and, more particularly, to an ink storage unit that can prevent reverse ink flowing causing ink leakage.
2. Description of the Related Art
Due to its advanced development, inkjet printing technology is broadly implemented in many types of printing apparatuses such as printers or facsimile machines. Inkjet printing technology principally consists of an inkjet print head that produces a high pressure to eject ink droplets out of the print head on the printed document, thereby forming an ink point thereon. By an adequate disposition of the numerous ink points on the printed documents, characters or graphics hence are formed. To continuously supply the inkjet print head with ink, an ink storage unit is traditionally used to store ink.
To prevent ink leakage out of the ink storage unit, a method of the prior art uses a pressure regulator that is disposed within an ink tank of the ink storage unit. The pressure regulator adequately regulates a pressure differential between the interior and the exterior of the ink tank by creating a negative pressure that keeps the ink from leaking out. Another method known in the prior art is to arrange an ink storage body made of porous material such as sponge or fabric within the ink tank. Via capillary action of the porous ink storage body, the ink can be stored and retained within the ink tank.
The introduction of ink within the ink tank 110 is usually achieved via ink injection by means of a syringe inserted through the air inlet 116 to the lower half of the ink storage body 120. However, ink stored in the ink storage body 120 may flow along the interface 130 between the outer surface of the ink storage body 120 and the inner sidewall of the ink tank and leak out through the air inlet 116. Therefore, the prior art further disposes a notch 121 on the outer surface of the ink storage body 120 facing the air inlet 116. The outer surface of the ink storage body 120 at that location is thereby separated a higher distance from the air inlet 116. Ink flowing through the interface 130 thus cannot contact with the air inlet 116 at the location of the notch 121 and, consequently, ink leakage is prevented.
However, the above disposition becomes deficient when the ink storage unit 100 is subject to significant external shaking, and ink leakage through the air inlet 116 hence still occurs.
An aspect of the invention is therefore to provide an ink storage unit that can effectively prevent ink leakage through the air inlet.
To accomplish the above and other objectives, an ink storage unit of the invention comprises an ink tank that defines an inner confinement space in which is placed an ink storage body to store and retain ink. The ink tank respectively includes an air inlet through which air passage into the ink tank is enabled, and an ink outlet through which ink output is achieved. The ink storage body is comprised of a first end portion approximately close to the air inlet and a second end portion approximately close to the ink outlet and relatively farther from the air inlet. An outer surface of the ink storage body includes a plurality of notches distributed along an interface between the ink storage body and the ink tank, thereby forming a plurality of gaps that locally separate the outer surface of the ink storage body from the sidewall of the ink tank to cut off ink flowing there along.
In accordance with the above objectives of the invention, the ink storage body is alternatively comprised of a first ink storage portion separated from a second ink storage portion via a spacing member. The first ink storage portion is placed approximately close to the air inlet and the second ink storage portion is placed approximately close to the ink outlet and relatively farther from the air inlet. The spacing member creates a spacing gap between the first and second ink storage portions so that reverse ink flowing causing ink leakage through the air inlet is prevented.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
The following detailed description of the embodiments and examples of the present invention with reference to the accompanying drawings is only illustrative and not limiting. Wherever possible in the following description and accompanying drawings, like reference numerals and symbols will refer to like elements and parts unless otherwise described.
Referring to
To prevent ink leakage through the air inlet 216, usually caused by an ink flow along an interface 230 between the ink storage body 220 and an inner sidewall of the ink tank 210, a plurality of notches 221b are formed on the ink storage body 220. More particularly, the notches 221b are distributed along the outer surface of the ink storage body 220 at first and second end portions 220a, 220b thereof. The first end portion 220a designates a portion of the ink storage body 220 that is approximately close to the air inlet 216, and the second end portion 220b designates a portion of the ink storage body 220 that is approximately close to the ink outlet 214 and relatively farther from the air inlet 216. The disposition of notches 221b hence creates a distribution of gaps 232 that cut off the continuity of the interface 230 to the air inlet 216. Via adequate geometry, curvature and depth of the gaps 232, the ink flowing path along the interface 230 is lengthened meanwhile the progression of ink flow is hampered. Reverse ink flow causing leakage through the air inlet 216 is thereby substantially reduced. An adequate geometry of the gaps 232 may be, for example, a circular recess that runs around the outer surface of the ink storage body 220 from the first portion 220a to the second end portion 220b.
Referring to
As illustrated in
As shown in FIG. 2 and
As described above, the invention therefore provides an ink storage unit that effectively prevents ink leakage through the air inlet due to ink flowing along the interface between the ink tank and the ink storage body received therein. For this purpose, an embodiment of the invention provides an ink storage body that is comprised of a plurality of notches formed on an outer surface thereof. The disposition of notches hence forms a distribution of gaps along the interface between the ink storage body and the ink tank that lengthens the ink flowing path to the air inlet and further hampers the progression of ink flow. Another embodiment of the invention provides an ink storage body that is comprised of first and second ink storage portions separated from each other via a spacing member placed there between, the first ink storage portion being close to the air inlet while the second ink storage portion being close to the ink outlet. The above spacing member creates a spacing gap between the first ink storage portion and the second ink storage portion that effectively prevents ink leakage to the air inlet.
It should be apparent to those skilled in the art that other structures that are obtained from various modifications and variations of various parts of the above-described embodiments of the invention would be possible without departing from the scope and spirit of the invention as illustrated herein. Therefore, the above description of embodiments and examples only illustrates specific ways of making and performing the invention that, consequently, should cover variations and modifications thereof, provided they fall within the inventive concepts as defined in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 91208003 U | May 2002 | TW | national |
This application is a divisional of a prior application Ser. No. 10/064,611, filed Jul. 31, 2002, now U.S. Pat. No. 6,817,706 which claims the priority benefit of Taiwan application serial no. 91208003, filed on May 31, 2002.
| Number | Name | Date | Kind |
|---|---|---|---|
| 6224200 | Higuma et al. | May 2001 | B1 |
| 20030020790 | Kotaki et al. | Jan 2003 | A1 |
| 20030052951 | Ujita et al. | Mar 2003 | A1 |
| 20030146960 | Chiu et al. | Aug 2003 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20040104983 A1 | Jun 2004 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10064611 | Jul 2002 | US |
| Child | 10707141 | US |
