An ink cartridge for a printer

<u>Background of the Invention</u>

0001The subject invention is directed toward the art of ink jet printers and, more particularly, to an improved ink storage cartridge for such printers.

0002Cartridges for a print head of an ink jet printer which contain a porous ink storage body have an opening in a cover for admitting air. For reducing evaporation losses, it has been proposed to provide the inner surface of the cover with a long capillary groove. One end of the groove ends in a fill opening, and the other end communicates with a vent hole through the cover. The groove is covered by a foil. On the outside surface of the cover, a label is sealed over the fill opening. For shipment, the vent hole is sealed by an adhesive tape.

0003GB-A-2 293 141 discloses an ink cartridge provided with a foil seal that is made up of two portions connected by a neck portion. When one of the portions is removed from the cartridge it is separated from the remaining portion at the neck portion.

<u>Summary of the Invention</u>

0004The object of the present invention is to simplify the manufacturing of a cartridge of the type described.

0005According to the present invention, the cartridge comprises a casing having a cover with a vent opening for admitting air into the interior of the casing. The outer face of the cover has a capillary groove with a first portion of the groove having a first end communicating with the opening and a second end communicating with an S-shaped second portion of the groove. The second portion includes three transverse branches and two connecting branches. The second portion ends at a location spaced from an edge of the cover. The outer face of the cover is covered by a sealed-on foil which overlaps one edge of the cover adjacent the second portion of the groove. Two cuts in the foil extend from opposed edges of the foil into areas between each of the transverse branches.

0006For shipment, the vent opening is completely sealed. Before or after insertion of the cartridge into the print head, the area of the foil with the overlapping edge is torn off. The foil then tears through from the end of the first cut towards the second cut and is peeled off. The S-shaped portion now communicates with the atmosphere.

0007Still other advantages and benefits of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description.

<u>Brief Description of the Drawings</u>

0008The invention may take physical form in certain parts and arrangements of parts, a preferred embodiment and method of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof, and wherein: <ul id="ul0001" list-style="none" compact="compact"><li>FIGURE 1 shows a top view on the cover of the cartridge according to the invention; and,</li><li>FIGURE 2 is a partial cross section through the cartridge.</li></ul>

<u>Detailed Description of the Preferred Embodiment</u>

0009Referring now to the drawings wherein the showings are for the purposes of illustrating the preferred embodiment of the invention only and not for purposes of limiting same, the cartridge <b>1</b> of the preferred embodiment shown in FIGURES 1 and 2 comprises a casing <b>2</b> with lateral walls <b>4</b> on the free ends of which a cover <b>5</b> is sealed, such as by being welded thereto. The cartridge contains a porous body <b>12</b>, e.g., of foamed synthetic material such as polyethylene. The cover has a recessed opening <b>13</b> for filling the body <b>12</b> with ink before shipment and for admitting air to a recessed space <b>14</b> of the body <b>12</b> during use of the cartridge in a print head of an ink jet printer. The recess <b>25</b> of the opening <b>13</b> is used to center and seal a filling tube for supplying the ink.

0010A narrow capillary is formed in the outer face <b>27</b> of the cover <b>5</b>. The capillary groove has a first portion <b>26</b> with a first end <b>28</b> that extends into the recess <b>25</b> and is thereby connected to the opening <b>13</b>. The other end <b>29</b> is connected to a second portion that comprises an S-shaped narrow capillary channel <b>30</b> with three transverse branches <b>31, 32, 33</b> parallel to the transverse edges <b>34</b> of the cover, and two connecting branches <b>35, 36</b> which are perpendicular to the transverse branches <b>31 - 34</b>. The channel <b>30</b> ends at a location spaced from the edge <b>34.</b> Preferably, the first portion <b>26</b> of the capillary groove has a meandering or zig-zag form.

0011A foil <b>42</b> is sealed onto the outer face <b>27</b> of the cover <b>5</b>. The foil <b>42</b> may be of aluminum coated with a thermoplastic for heat sealing or it may be a laminated or unlaminated thermoplastic foil. Alternatively, an adhesive tape may be used. The foil could also be coated with a hot melt adhesive. An end area <b>43</b> of the foil <b>42</b> overlaps the transverse edge <b>34</b> of the cover <b>5</b> adjacent the channel. Two transverse cuts <b>44</b>, <b>45</b> are cut through the foil <b>42</b> starting from opposed longitudinal edges <b>46</b>, <b>47</b> of the foil <b>42</b> and ending in the region between each two adjacent transverse branches <b>31, 32</b> and <b>32, 33</b>. The area of the foil <b>42</b> to the left of the cut <b>45</b> in FIGURE 1 is printed as a label for the cartridge. The area to the right of the cut <b>45</b> is torn off before use of the cartridge <b>1</b> in a printer. To this end, the foil <b>42</b> is grabbed at the overlapping area <b>43</b> and peeled off the cover <b>5</b> until the cut <b>44</b> is reached. Then the foil <b>42</b> is torn through starting from the inner end of cut <b>44</b>. Since the cuts <b>44, 45</b> overlap by a substantial amount in their longitudinal direction, the tear line <b>48</b> which may be at an arbitrary angle to the longitudinal edges (indicated with dotted lines in FIGURE 1) will automatically end at the cut <b>45</b>. Thus, the branch <b>32</b> of the channel <b>30</b> is open to the atmosphere. The remaining foil <b>42</b> to the left of cuts <b>44, 45</b> remains as a label on the cover <b>5</b> and as an outside seal for the capillary groove and part of the channel <b>30</b>. In case the user tears the area <b>43</b> sideways, the tear line <b>48</b> crosses one of the branches <b>35</b> or <b>31</b>.

0012The same opening <b>13</b> is used for ink filling during production and for air admittance during use. A single foil is used as a label, as a seal for the fill opening, as a cover for the capillary groove, and as a hermetic seal for shipment. Therefore, an economic manufacturing of the cartridge is achieved. Because of the two overlapping cuts <b>44, 45</b>, the foil <b>42</b> can be torn off in the length direction of the cover <b>5</b>. Therefore, no overlap over the longitudinal edge <b>46</b> is required to the right of cut <b>44</b>. This enables an inexpensive production of the labels from a continuous band.