Patent Publication Number: US-6220701-B1

Title: Ink cartridge and method of disassembling the same

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an ink cartridge for use with an ink jet printer, which is produced in view of recycle of resources, and a method of disassembling the same. 
     2. Prior Art 
     Conventionally, an ink cartridge to be removably loaded in an ink jet printer was proposed e.g. by Japanese Laid-Open Patent Publication (Kokai) No. 8-132636. The ink cartridge is a type which is connected to a print head by inserting a head needle provided on a print head side of an ink jet printer into an ink delivery port of the ink cartridge. The ink cartridge includes a cartridge casing comprised of a lower casing serving as a casing body and an upper casing serving as a casing lid, and an ink-absorbent material filling the cartridge casing. The ink delivery port is formed through a bottom of the lower casing, and a filter is arranged inward of the ink delivery port between the ink delivery port and the ink-absorbent material. Further, the ink delivery port has a rubber packing mounted on an inner periphery thereof for intimate contact with the head needle connected to the ink cartridge. 
     The upper casing is formed with an ink-charging port and an air inlet port both extending through a top wall thereof, and a meandering air groove continuous with the air inlet port in the top surface thereof. Further, a delivery port-sealing film is affixed to the bottom surface of the lower casing by thermo-compression bonding such that it seals the ink delivery port, and an air inlet port-sealing film are affixed to the top surface of the upper casing by thermo-compression bonding such that it seals the ink-charging port, the air inlet port, and the meandering air groove. 
     The upper and lower casings, the delivery port-sealing film, and the air inlet port-sealing film are formed of polypropylene, whereas the ink-absorbent material, the filter, and the rubber packing are formed of urethane, stainless steel, and a synthetic rubber, respectively. 
     In order to disassemble the conventional ink cartridge constructed as above, for the purpose of recycle, it is required to separate the upper and lower casings, the delivery port-sealing film, and the air inlet port-sealing film (i.e. the component parts formed of polypropylene), each of which is recyclable, from the other component parts which cannot be recycled. To do this, first, the cartridge casing is cut so as to take out the ink-absorbent material and the filter therefrom. However, when the cartridge casing is cut, the ink-absorbent material is cut together with the cartridge casing, which makes assortment of the disassembled component parts troublesome. Further, the ink-absorbent material and the filter are taken out from a portion of the cartridge casing cut open, whereas the rubber packing is required to be taken out after the delivery port-sealing film being peeled off, in a direction opposite to the direction in which the ink-absorbent material is removed. This also makes the separation and assortment of the disassembled component parts troublesome. 
     SUMMARY OF THE INVENTION 
     It is a first object of the invention to provide an ink cartridge having a construction which allows easy disassembly of the ink cartridge as well as easy assortment of disassembled component parts of the same according to their materials. 
     It is a second object of the invention to provide a method of disassembling the ink cartridge. 
     To attain the first object, according to a first aspect of the invention, there is provided an ink cartridge comprising: 
     a casing body, the casing body having a bottom formed with an ink delivery port extending therethrough; 
     a casing lid joined to the casing body, the casing lid being formed with an air inlet port extending therethrough; 
     the casing body and the casing lid forming a cartridge casing, 
     an ink-absorbent material filling the cartridge casing; 
     a delivery port-sealing film sealing the ink delivery port; 
     an air inlet port-sealing film sealing the air inlet port; and 
     a filter arranged within the casing body at a location inward of the ink delivery port by being inserted thereto from an ink-absorbent material side such that the filter is located between the ink delivery port and the ink-absorbent material, 
     wherein the casing body, the casing lid, the delivery port-sealing film, and the air inlet port-sealing film are formed of a resin material of the same kind, and 
     wherein a gap is provided between an underside of the casing lid and a top surface of the ink-absorbent material, for allowing the cartridge casing to be cut thereacross. 
     According to this ink cartridge, a gap is created between the underside of the casing lid and the top surface of the ink-absorbent material for allowing the cartridge casing to be cut thereacross. This makes it possible to cut the cartridge casing in two without cutting the ink-absorbent material. Further, the ink-absorbent material and the filter accommodated within the cartridge casing can be simultaneously and easily taken out from an opening of a cut portion of the cartridge casing. 
     Preferably, the underside of the casing lid is formed with a rib protruding downward for holding down the ink-absorbent material. 
     According to this preferred embodiment, it is possible to positively prevent the ink-absorbent material from invading the gap e.g. due to vibration. Further, it is possible to prevent part of the ink-absorbent material from being drawn into the air inlet port when the cartridge casing is evacuated via the air inlet port during manufacturing, thereby preventing ink absorbed in the ink-absorbent material from being sucked via the air inlet port. 
     Preferably, the resin material of the same kind is an identical recyclable resin material. 
     According to this preferred embodiment, it is possible to easily recycle the identical recyclable resin material after the ink cartridge is used up. 
     For example, the identical recyclable resin material is polypropylene. 
     To attain the second object, according to a second aspect of the invention, there is provided a method of disassembling an ink cartridge according to the first aspect of the invention. 
     The method is characterized by comprising the steps of: 
     holding the ink cartridge in a vertically upside-down position; 
     cutting the ink cartridge horizontally across the gap; and 
     extruding the filter and the ink-absorbent material by inserting a pusher from the ink delivery port. 
     According to this method, an ink cartridge held in a vertically upside-down position is cut horizontally across the gap, and a casing lid-side portion of the ink cartridge casing falls. Therefore, it is possible to easily cut the ink cartridge in two such that the casing lid-side portion is separated and falls from the remaining portion without cutting the ink-absorbent material to mix the same with the casing lid side portion of the cartridge casing. Further, when the filter and the ink-absorbent material are extruded by inserting the pusher from the ink delivery port, they also fall, whereby they are easily separated from the casing body. That is, the ink cartridge can be properly disassembled in a single cutting operation and a single extruding operation. 
     Preferably, the step of cutting the ink cartridge and the step of extruding the filter and the ink-absorbent material are carried out in respective different work areas. 
     According to this preferred embodiment, even if cuttings are produced e.g. by sawing of the cartridge, it is possible to positively collect the cuttings together with the casing lid. 
     The above and other objects, features, and advantages of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is a top plan view of an ink cartridge according to an embodiment of the present invention; 
     FIG. 1B is a longitudinal sectional view of the ink cartridge: 
     FIG. 1C is a transverse sectional view of the ink cartridge: 
     FIG. 2A is a perspective view showing the top of the ink cartridge; 
     FIG. 2B is a perspective view showing the bottom of the ink cartridge; and 
     FIGS. 3A to  3 C are explanatory views showing a sequence of steps of disassembling the ink cartridge. 
    
    
     DETAILED DESCRIPTION 
     The invention will now be described in detail with reference to the drawings showing embodiments thereof. An ink cartridge according to the present invention is used for color printing. FIGS. 1A to  1 C show the construction of the ink cartridge, while FIGS. 2A and 2B show appearances of the ink cartridge in perspective. As shown in these figures, the ink cartridge  1  has a cartridge casing  2  generally in the form of a rectangular parallelepiped. The cartridge casing  2  is comprised of a lower casing  2   a  serving as a casing body, and an upper casing  2   b  serving as a casing lid. The upper and lower casings  2   b  and  2   a  are each formed of polypropylene, and the upper casing  2   b  is welded (by vibration welding) to the lower casing  2   a  in a manner closing an open upper end of the lower casing  2   a  to form a unitary member. 
     The cartridge casing  2  has an inside thereof divided by three partition walls  3  into four ink reservoirs  4 . The four ink reservoirs  4  contain cyan, magenta, yellow, and black inks, respectively, each of which is stored in a state absorbed in an ink-absorbent material  5 . The ink-absorbent materials  5  are formed e.g. of urethane foam. 
     The lower casing  2   a  has a bottom thereof formed with four ink delivery ports  6  opening into the respective ink reservoirs  4 . The ink cartridge  1  is tightly connected to a print head in surface contact therewith (or removed from the same) via the respective ink delivery ports  6 . Further, on an underside surface of the bottom of the lower casing  2   a , there are formed a pair of protect ribs  7 ,  7  protruding downward and extending longitudinally on opposite sides of a row of the four ink delivery ports  6 . A delivery port-sealing film  8  of polypropylene for sealing the four ink delivery ports  6  is affixed by thermo-compression bonding to a zone of the underside surface of the bottom of the lower casing  2   a  between the pair of protect ribs  7 , 7 . The delivery port-sealing film  8  is peeled off immediately before the ink cartridge is put into use. 
     The ink delivery ports  6  each have a filter  9  arranged therein at a location downstream of the ink-absorbent material  5  in a manner facing an opening of the ink delivery port  6 . The ink absorbed in the ink-absorbent material  5  is supplied to the print head through the filter  9 . The filter  9  and the ink-absorbent material  5  are mounted into the lower casing  2   a  from the upper end of the same in the mentioned order. 
     The upper casing  2   b  has four ink-charging ports  11  and four air inlet ports  12  formed therethrough in a manner corresponding to the respective four ink delivery ports  6 . Further, formed in a top surface of the upper casing  2   b  are four meandering air grooves  13 , each of which has a proximal end continuous with a corresponding one of the air inlet ports  12 . On the other hand, distal ends of the four meandering air grooves  13  are located close to the center of the top surface of the upper casing  2   b . When a portion of an air inlet port-sealing film  14 , referred to hereinafter, covering the distal ends of the four meandering air grooves  13  is peeled off, the air inlet ports  12  are made open to the atmosphere via the meandering air grooves  13 . 
     More specifically, the upper casing  2   b  has the air inlet port-sealing film  14  affixed to the whole top surface thereof by thermo-compression bonding, for sealing the ink-charging ports  11 , the air inlet ports  12 , and the meandering air grooves  13 , and when a portion of the air inlet port-sealing film  14  covering the distal ends of the meandering air grooves  13  is torn off along perforations or the like, the distal ends of the meandering air grooves (meandering passages)  13  are made open to the atmosphere. As the inks within the ink cartridge  1  are supplied to the print head, air is drawn in through each of the meandering air grooves  13  by an amount equivalent to an amount of a corresponding ink supplied to the print head, and introduced into a corresponding ink reservoir of the ink cartridge  1  via a corresponding one of the air inlet ports  12 . The meandering air grooves  13  are provided for preventing evaporation of solvent contained in each ink. The air inlet port-sealing film  14  is formed of polypropylene. 
     The upper casing  2   b  has an underside surface thereof formed with four pairs of spacer ribs  15  protruding downward into the respective ink reservoirs  4 . The pairs of spacer ribs  15  are integrally formed with the upper casing  2   b , for holding down the respective ink-absorbent materials  5 . Each of the spacer ribs  15  is formed to have a sufficient protrusion dimension for providing a gap  16  between the underside surface of the upper casing  2   b  and a top surface of the ink-absorbent material  5 . This gap  16  is provided so as to allow the cartridge casing  2  to be cut thereacross. More specifically, as described in detail hereinafter, the ink cartridge  1  is cut horizontally (i.e. along a plane extending in parallel with the upper casing  2   b ) across the gap  16  when the ink cartridge  1  is disassembled. In FIG. 1C, reference numeral  17  designates a positioning projection for preventing the ink cartridge  1  from being erroneously mounted with the front side and the rear side reversed, in a cartridge holder arranged on a print head side of an ink jet printer. 
     Next, the method of disassembling the ink cartridge  1  will be described with reference to FIGS. 3A to  3 C. As described above, the upper and lower casings  2   b ,  2   a  of the ink cartridge  1 , the delivery port-sealing film  8 , and the air inlet port-sealing film  14  are formed of polypropylene which is recyclable, while the ink-absorbent materials  5  and the filters  9  are formed of other materials, respectively. Therefore, according to this disassembling method, the upper and lower casings  2   b ,  2   a  and the two films  8 ,  14  are disassembled completely separate from the ink-absorbent materials  5  and the filters  9 . 
     First, as shown in FIG. 3A, the ink cartridge  1  is turned upside down and held in this position, i.e. a vertically upside-down position by a holding jig  21 . Then, the ink cartridge  2  is cut horizontally across the gaps  16  e.g. by using a sawing cutter  22 . When the ink cartridge  1  is cut, the upper casing  2   b  and an upper end portion of the lower casing  2   a  continuous therewith are separated and fall. At the same time, portions of the spacer ribs  15  cut off from the upper casing  2   b  separate from the respective ink-absorbent materials  5  and also fall (see FIG.  3 B). On the other hand, the ink-absorbent materials  5  filled in the ink cartridge  1  in a compressed state cannot fall even when the ink cartridge  1  is cut. 
     The remainder of the ink cartridge  1  held by the holding jig  21  is carried to another work area. Then, a cylindrical pusher  23  is inserted into the ink cartridge  1  from each of the ink delivery ports  6  to extrude the filter  9  and the ink-absorbent material  5  from the lower casing  2   a . The filter  9  and the ink-absorbent material  5  are extruded from the lower casing  2   a  and fall (FIG.  3 C). When the above-mentioned sequence of disassembling operations is completed, the lower casing  2   a  held by the holding jig  21 , as well as the upper casing  2   b  (including the air inlet port-sealing film  14 ) and the spacer ribs  15  which were cut off in the first work area are collected together with cuttings. Further, the filters  9  and the ink-absorbent materials  5  are collected separately from the above component parts. In general, an ink cartridge  1  to be disassembled is a used-up one with a delivery port-sealing film  8  already peeled off. Therefore, it is preferable that the delivery port-sealing film  8  is collected separately by a special method therefor. 
     As described above, according to the present embodiment, the spacer ribs  15  are provided to hold down the ink-absorbent materials  5  such that the gap  16  is created which is large enough to permit the ink cartridge  1  to be cut thereacross between the underside surface of the upper casing  2   b  and the top surface of the ink-absorbent material  5 . In disassembling the used cartridge  1 , the ink cartridge  1  is cut horizontally across the gap  16 . Therefore, it is possible to cut the ink cartridge  1  without cutting the ink-absorbent materials  5 , as a result of which the disassembled component parts can be assorted according to their materials with ease. Additionally, since the cutting of the ink cartridge  1  and the extrusion of the filters  9  and the ink-absorbent materials  5  from the ink cartridge  1  are carried out in different work areas, cuttings produced during the cutting can also be collected positively. 
     Further, since the filter  9  and the ink-absorbent material  5  are mounted into each of the ink reservoirs  5  from the upper end of the lower casing  2   a  in the mentioned order, it is possible to extrude the filter  9  and the ink-absorbent material  5  from the ink cartridge  1  easily in a single extruding operation. This facilitates disassembly of the ink cartridge  1  and assortment of the component parts of the same according to their materials, thereby enabling positive recycle of resources. 
     Although in the above embodiment, the upper and lower casings, the delivery port-sealing film, and the air inlet port-sealing film are each formed of polypropylene, this is not limitative, but it goes without saying that they may be formed of any other suitable recyclable resin. 
     It is further understood by those skilled in the art that the foregoing is a preferred embodiment of the invention, and that various changes and modifications may be made without departing from the spirit and scope thereof.