Patent Publication Number: US-7905572-B2

Title: Apparatus for mounting a removable ink tank in an imaging apparatus

Description:
FIELD OF THE INVENTION 
     The present invention relates to an imaging apparatus, and, more particularly, to an apparatus for mounting a removable ink tank in an imaging apparatus. 
     BACKGROUND OF THE INVENTION 
     An imaging apparatus, such as an ink jet printer, forms an image on a print medium, such as paper, by applying ink to the print medium. The ink may be contained in one or more replaceable supply cartridges. Examples of such replaceable supply cartridges include a replaceable ink tank and an ink jet printhead cartridge. An ink jet printhead cartridge, for example, includes both an ink tank and an ink jet micro-fluid ejection device, whereas an ink tank does not include the micro-fluid ejection device. 
     One such ink jet printer mounts a plurality of ink tanks, with each ink tank containing a supply of a particular color of ink, e.g., black, cyan, magenta, and yellow. Each ink tank is mounted to a micro-fluid ejection device that is separately mounted to the printhead carrier, and is commonly referred to as an on-carrier ink tank system. In an on-carrier ink tank system, the ink is transferred from the tank to the micro-fluid ejection device through as series of fluid interfaces. The ink typically is suspended in the tank in a felt or foam. Care must be taken to ensure firm mounting of each removable ink tank in relation to the printhead assembly, so as to, for example, facilitate the formation of an adequate seal between each ink tank and the printhead assembly at the fluid interface. 
     SUMMARY OF THE INVENTION 
     The present invention provides an apparatus for mounting a removable ink tank in an imaging apparatus, such as for example, an ink jet printer. 
     The invention, in one form thereof, is directed to an apparatus for mounting a removable ink tank having an ink output port to a printhead body that mounts a micro-fluid ejection device, the printhead body defining a filtered ink/air reservoir. The apparatus includes a filter cap configured for attachment to the printhead body. The filtered ink/air reservoir is located in a region between the filter cap and the micro-fluid ejection device. The filter cap has a filter cap body configured to operably engage the ink output port of the removable ink tank and has an ink tank latching mechanism configured to secure the removable ink tank to the filter cap in a releasable manner. 
     The invention, in another form thereof, is directed to an imaging apparatus configured for mounting a removable ink tank having an ink output port. The imaging apparatus includes a printhead carrier configured for reciprocating motion along a main scan axis. A printhead body is mounted to the printhead carrier. The printhead body defines a filtered ink/air reservoir. A micro-fluid ejection device is attached to the printhead body. A filter cap is attached to the printhead body. The filtered ink/air reservoir is located in a region between the filter cap and the micro-fluid ejection device. The filter cap has a filter cap body configured to operably engage the ink output port of the removable ink tank and has an ink tank latching mechanism configured to secure the removable ink tank to the filter cap in a releasable manner. 
     The invention, in another form thereof, is directed to a removable ink tank configured to be mounted to a printhead carrier of an imaging apparatus, wherein a printhead body having a micro-fluid ejection device is mounted to the printhead carrier, the printhead body defining a filtered ink/air reservoir and having a filter cap attached to the printhead body, the filtered ink/air reservoir being located in a region between the fiber cap and the micro-fluid ejection device, the filter cap having a filter cap body and an ink tank latching mechanism. The removable ink tank includes a base configured with an ink output port. A side wall structure has a bottom end and a top end opposite to the bottom end, the bottom end being attached to the base, and has a front wall and a rear wall opposite to the front wall. A cover is attached to the top end of the side wall structure. A latching tab extends outwardly from a first region of the removable ink tank near an intersection of the cover and the top end of the side wall structure along the front wall. The latching tab is positioned to engage the ink tank latching mechanism of the filter cap. A rib extends outwardly from a second region of the removable ink tank near an intersection of the base and the bottom end of the side wall structure along the rear wall. The rib is located to engage a portion of the printhead carrier. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a diagrammatic depiction of an imaging system embodying the present invention. 
         FIG. 2A  is a perspective view of the printhead carrier of  FIG. 1 , with the printhead assembly and ink tanks removed. 
         FIG. 2B  is a bottom view of the ink tanks of  FIG. 2A . 
         FIG. 3  is a perspective view of the printhead carrier of  FIG. 1  with the printhead assembly installed. 
         FIG. 4  is a side partial section view of the printhead assembly and a color ink tank, with a portion broken away, and with the ink tank partially installed in the printhead assembly. 
         FIG. 5  is a side partial section view of the printhead assembly and a monochrome ink tank, with a portion broken away, and with the ink tank fully installed in the printhead assembly. 
         FIG. 6  is a side partial section view of a printhead assembly and an ink tank, illustrating removal of the ink tank from the printhead assembly. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , there is shown a diagrammatic depiction of an imaging system  10  embodying the present invention. Imaging system  10  may include a host  12  and an imaging apparatus  14 . Imaging apparatus  14  communicates with host  12  via a communications link  16 . Communications link  16  may be established by a direct cable connection, wireless connection or by a network connection such as for example an Ethernet local area network (LAN). 
     Alternatively, imaging apparatus  14  may be a standalone unit that is not communicatively linked to a host, such as host  12 . For example, imaging apparatus  14  may take the form of an all-in-one, i.e., multifunction, machine that includes standalone copying and facsimile capabilities, in addition to optionally serving as a printer when attached to a host, such as host  12 . 
     Host  12  may be, for example, a personal computer including an input/output (I/O) device, such as keyboard and display monitor. Host  12  further includes a processor, input/output (I/O) interfaces, memory, such as RAM, ROM, NVRAM, and a mass data storage device, such as a hard drive, CD-ROM and/or DVD units. During operation host  12  may include in its memory a software program including program instructions that function as an imaging driver, e.g., printer driver software, for imaging apparatus  14 . Alternatively, the imaging driver may be incorporated, in whole or in part, an imaging apparatus  14 . 
     In the embodiment of  FIG. 1 , imaging apparatus  14  includes a controller  18 , a print engine  20  and a user interface  22 . 
     Host  12  is in communication with controller  18  of imaging apparatus  14  via communications link  16 . The imaging device facilitates communication between imaging apparatus  14  and host  12 , and may provide formatted print data to imaging apparatus  14 , and more particularly, to print engine  20 . Alternatively, however, all or a portion of the imaging driver may be located in controller  18  of imaging apparatus  14 . For example, where imaging apparatus  14  is a multifunction machine having standalone capabilities, controller  18  of imaging apparatus  14  may include the imaging driver configured to support a copying function, and/or a fax-print function, and may be further configured to support a printer function. 
     Controller  18  includes a processor unit and associated memory, and may be formed as an Application Specific Integrated Circuit (ASIC). Controller  18  communicates with print engine  20  via a communications link  24 . Controller  18  communicates with user interface  22  via a communications link  26 . Communications link  24  and  26  may be established, for example, by using standard electrical cabling or bus structures, or by wireless connection. 
     Print engine  20  may be, for example, an ink jet print engine configured for forming an image on a sheet of print media  28 , such as a sheet of paper, transparency or fabric. 
     Print engine  20  may include, for example, a reciprocating printhead carrier  30 . Referring now also to  FIGS. 2A and 3 , a printhead carrier  30  is mechanically and electrically configured to mount and carry at least one printhead assembly  32  that includes at least one ink jet micro-fluid ejection device  34 . Printhead carrier  30  transports printhead assembly  32 , and in turn ink jet micro-fluid ejection device  34 , in a reciprocating manner in a bi-directional main scan direction, i.e., axis,  36  over an image surface of the sheet of print media  28  during a printing operation. 
     Printhead assembly  32  is configured to mount and carry a plurality of removable ink tanks  38 , and to facilitate an ink transfer from one or more of the plurality of ink tanks  38  to micro-fluid ejection device  34 . The plurality of ink tanks  38  may include, as in the example of  FIGS. 1 ,  2 A, and  3 , a monochrome ink tank  38 - 1 , e.g., containing black ink, and three color ink tanks  38 - 2 ,  38 - 3 ,  38 - 4 , e.g., containing cyan, magenta, and yellow inks. Micro-fluid ejection device  34  may include an ink jet nozzle array for each color of ink. 
     As best shown in  FIGS. 2A and 4 , printhead assembly  32  includes a printhead body  40  and a filter cap  42 . Micro-fluid ejection device  34  is attached to a snout portion  44  of printhead body  40 . Printhead body  40  is configured to define individual filtered ink/air reservoirs  46  that are in fluid communication with micro-fluid ejection device  34 . Filter cap  42  is attached to printhead body  40  via a hermetic seal, such as by welding or adhesive attachment. Each filtered ink/air reservoir  46  is located in a region between filter cap  42  and micro-fluid ejection device  34 . Each filtered ink/air reservoir  46 , for example, stores air that is ingested during printing. 
     Referring to  FIGS. 2A ,  3  and  4 , filter cap  42  has a filter cap body  48  configured with a plurality of fluid interface devices  50 , individually identified as fluid interface device  50 - 1 , fluid interface device  50 - 2 , fluid interface device  50 - 3 , and fluid interface device  50 - 4  that operably engages and facilitates fluid communication with the respective ink output ports of ink tanks  38 - 1 ,  38 - 2 ,  38 - 3  and  38 - 4 , respectively. 
     As shown, for example, in  FIG. 4  including color ink tank  38 - 2 , fluid interface device  50 - 2  includes a standpipe  51 - 2  in fluid communication with filtered ink/air reservoir  46 - 2  via a filter  52 - 2 , and carries a wick  54 - 2 . Referring to  FIG. 2B , ink tanks  38 - 1 ,  38 - 2 ,  38 - 3  and  38 - 4  include a respective ink output port  56 - 1 ,  56 - 2 ,  56 - 3  and  56 - 4 . Wick  54 - 2 , for example, facilitates fluid communication with ink output port  56 - 2  of ink tank  38 - 2 . For example, the ink in ink tank  38 - 2  is suspended in a felt or foam, and is transferred to wick  54 - 2  when wick  54 - 2  contacts the felt, or foam, contained in ink tank  38 - 2 . Also, wick  54 - 2  is in fluid communication with filter  52 - 2 . Filter  52 - 2  acts as the seal for filtered ink/air reservoir  46 - 2  above the via of the chip forming a portion of micro-fluid ejection device  34 . Each of the plurality of fluid interface devices  50  and the plurality of ink tanks  38  is similarly configured as described above with respect to fluid interface device  50 - 2  and ink tank  38 - 2 . 
     Referring to  FIGS. 2A and 3 , filter cap  42  further includes ink tank latching mechanisms  58 - 1 ,  58 - 2 ,  58 - 3  and  58 - 4  configured to secure, in a releasable manner, the respective removable ink tanks  38 - 1 ,  38 - 2 ,  38 - 3 , and  38 - 4  to filter cap  42 , and in turn, to printhead assembly  32  and printhead carrier  30 . Each of ink tank latching mechanisms  58 - 1 ,  58 - 2 ,  58 - 3  and  58 - 4  includes a respective of cantilever arm  60 - 1 ,  60 - 2 ,  60 - 3 , and  60 - 4  that has a proximal end  62  and a distal end  64 . Proximal end  62  of each cantilever arm is attached to filter cap body  48  of filter cap  42 . Distal end  64  is the free end of individual cantilever arms  60 - 1 ,  60 - 2 ,  60 - 3 , and  60 - 4 . Distal end  64  of each of cantilever arms  60 - 1 ,  60 - 2 ,  60 - 3 , and  60 - 4  has a respective latch feature  66 - 1 ,  66 - 2 ,  66 - 3 ,  66 - 4 , which in this embodiment is in the form of an opening defining a respective latch surface  68 - 1 ,  68 - 2 ,  68 - 3  and  68 - 4  for engaging a portion of the respective removable ink tanks  38 - 1 ,  38 - 2 ,  38 - 3 , and  38 - 4 . 
     Referring to  FIGS. 2A ,  2 B and  3 , ink tank  38 - 1  includes a base  70 - 1  configured with ink output port  56 - 1 . Ink tank  38 - 1  also includes a side wall structure  72 - 1  having a bottom end  74  and a top end  76  opposite to the bottom end  74 . Bottom end  74  of side wall structure  72 - 1  is attached to base  70 - 1 . Side wall structure  72 - 1  includes a front wall  78 - 1  and a rear wall  80 - 1  opposite to front wall  78 - 1 . A cover  82 - 1  is attached to the top end  76  of side wall structure  72 - 1 . A latching tab  84 - 1  extends outwardly from a region of the removable ink tank near an intersection of the cover  82 - 1  and the top end  76  of side wall structure  72 - 1  along front wall  78 - 1 . Latching tab  84 - 1  is positioned to engage ink tank latching mechanism  58 - 1  of filter cap  42 . A rib  86 - 1  extends outwardly from a region of the removable ink tank near an intersection of base  70 - 1  and the bottom end  74  of side wall structure  72 - 1  along rear wall  80 - 1 . Rib  86 - 1  may be formed integral with ink tank  38 - 1 , or may formed as part of a façade attached to ink tank  38 - 1 , but in either case is considered to be a part of ink tank  38 - 1 . Rib  86 - 1  is located to engage a portion of the printhead carrier  30 . Rib  86 - 1  may be formed, for example, as a key member having a shape or location that distinguishes one type of ink tank from another type of ink tank. The term “type” refers to, for example, the color of ink and/or the composition of the ink contained in the ink tank. 
     Ink tank  38 - 2  includes a base  70 - 2  configured with ink output port  56 - 2 . Ink tank  38 - 2  includes a side wall structure  72 - 2  having bottom end  74  and top end  76  opposite to the bottom end  74 . Bottom end  74  of side wall structure  72 - 2  is attached to base  70 - 2 . Side wall structure  72 - 2  includes a front wall  78 - 2  and a rear wall  80 - 2  opposite to front wall  78 - 2 . A cover  82 - 2  is attached to the top end  76  of side wall structure  72 - 2 . A latching tab  84 - 2  extends outwardly from a region of the removable ink tank near an intersection of the cover  82 - 2  and the top end  76  of side wall structure  72 - 2  along front wall  78 - 2 . Latching tab  84 - 2  is positioned to engage ink tank latching mechanism  58 - 2  of filter cap  42 . A rib  86 - 2  extends outwardly from a region of the removable ink tank near an intersection of base  70 - 2  and the bottom end  74  of side wall structure  72 - 2  along rear wall  80 - 2 . Rib  86 - 2  may be formed integral with ink tank  38 - 2 , or may formed as part of a façade attached to ink tank  38 - 2 , but in either case is considered to be part of ink tank  38 - 2 . Rib  86 - 2  is located to engage a portion of the printhead carrier  30 . Rib  86 - 2  may be formed, for example, as a key member that distinguishes one type of ink tank from another type of ink tank. 
     Ink tank  38 - 3  includes a base  70 - 3  configured with ink output port  56 - 3 . Ink tank  38 - 3  includes a side wall structure  72 - 3  having bottom end  74  and top end  76  opposite to the bottom end  74 . Bottom end  74  of side wall structure  72 - 3  is attached to base  70 - 3 . Side wall structure  72 - 3  includes a front wall  78 - 3  and a rear wall  80 - 3  opposite to front wall  78 - 3 . A cover  82 - 3  is attached to the top end  76  of side wall structure  72 - 3 . A latching tab  84 - 3  extends outwardly from a region of the removable ink tank near an intersection of the cover  82 - 3  and the top end  76  of side wall structure  72 - 3  along front wall  78 - 3 . Latching tab  84 - 3  is positioned to engage ink tank latching mechanism  58 - 3  of filter cap  42 . A rib  86 - 3  extends outwardly from a region of the removable ink tank near an intersection of base  70 - 3  and the bottom end  74  of side wall structure  72 - 3  along rear wall  80 - 3 . Rib  86 - 3  may be formed integral with ink tank  38 - 3 , or may formed as part of a façade attached to ink tank  38 - 3 , but in either case is considered to be a part of ink tank  38 - 3 . Rib  86 - 3  is located to engage a portion of the printhead carrier  30 . Rib  86 - 3  may be formed, for example, as a key member that distinguishes one type of ink tank from another type of ink tank. 
     Ink tank  38 - 4  includes a base  70 - 4  configured with ink output port  56 - 4 . Ink tank  38 - 4  includes a side wall structure  72 - 4  having bottom end  74  and top end  76  opposite to the bottom end  74 . Bottom end  74  of side wall structure  72 - 4  is attached to base  70 - 4 . Side wall structure  72 - 4  includes a front wall  78 - 4  and a rear wall  80 - 4  opposite to front wall  78 - 4 . A cover  82 - 4  is attached to the top end  76  of side wall structure  72 - 4 . A latching tab  84 - 4  extends outwardly from a region of the removable ink tank near an intersection of the cover  82 - 4  and the top end  76  of side wall structure  72 - 4  along front wall  78 - 4 . Latching tab  84 - 4  is positioned to engage ink tank latching mechanism  58 - 4  of filter cap  42 . A rib  86 - 4  extends outwardly from a region of the removable ink tank near an intersection of base  70 - 4  and the bottom end  74  of side wall structure  72 - 4  along rear wall  80 - 4 . Rib  86 - 4  may be formed integral with ink tank  38 - 4 , or may formed as part of a façade attached to ink tank  38 - 4 , but in either case is considered to be a part of ink tank  38 - 4 . Rib  86 - 4  is located to engage a portion of the printhead carrier  30 . Rib  86 - 4  may be formed, for example, as a key member that distinguishes one type of ink tank from another type of ink tank. 
     As can be best seen in  FIG. 4 , printhead carrier  30  includes a pivot mechanism  88  positioned to engage and receive each of the ribs  86 - 1 ,  86 - 2 ,  86 - 3  and  86 - 4  of ink tanks  38 - 1 ,  38 - 2 ,  38 - 3 , and  38 - 4 , respectively. Pivot mechanism  88  may be configured with a slot  90  defining a keying feature to selectively receive only a specific ink tank having a proper key member corresponding to the keying feature at a particular location within printhead carrier  30 . For example, each of ribs  86 - 1 ,  86 - 2 ,  86 - 3  and  86 - 4  may have a unique shape to serve as a respective key member, and the shape of the slot  90  of pivot mechanism  88  may be defined to only accommodate ink tanks  38 - 1 ,  38 - 2 ,  38 - 3 , and  38 - 4  in a particular sequence across the width of printhead assembly  32 . 
     Alternatively, each of ink tanks  38 - 1 ,  38 - 2 ,  38 - 3 , and  38 - 4  may have a key pocket, such as key pocket  89 - 2  shown in  FIG. 4  near an intersection of base  70 - 2  and the bottom end  74  of side wall structure  72 - 2  along rear wall  80 - 2 . Likewise, printhead carrier  30  may include a corresponding number of upwardly extending key protrusions, such as key protrusion  91 - 2  shown in  FIG. 4 , each of which being configured to be selectively received only by a corresponding one of the key pockets of ink tanks  38 - 1 ,  38 - 2 ,  38 - 3 , and  38 - 4 . 
       FIGS. 4 and 5  illustrate an ink tank loading sequence using ink tanks  38 - 1  and  38 - 2  as example. 
     Referring now to  FIG. 4 , using color ink tank  38 - 2  as the example, as ink tank  38 - 2  is installed in printhead assembly  32 , rib  86 - 2  located in a lower portion of rear wall  80 - 2  of ink tank  38 - 2  is inserted into slot  90  of pivot mechanism  88  of printhead carrier  30 . At this stage, base  70 - 2  of ink tank  38 - 2  engages an associated spring  92  extending upwardly from the floor of filter cap  42 . This process is similar for each of the color ink tanks  38 - 2 ,  38 - 3 ,  38 - 4 , and monochrome ink tank  38 - 1 . 
     As shown in  FIG. 5 , using monochrome ink tank  38 - 1  as the example, during ink tank mounting the user presses downwardly on cover  82 - 1  of ink tank  38 - 1  in direction  94  toward the filter cap body  48  of filter cap  42 , and in turn pivots ink tank  38 - 2  downwardly about pivot mechanism  88  of printhead carrier  30 , while compressing the associated spring  92 , and deflecting cantilever arm  60 - 1  in direction  96 . An ink tank  38 - 1  moves downward in direction  94 , the apex of the front wall  78 - 1  and base  70 - 1  of ink tank  38 - 1  contacts a ramp feature  95  in the front of filter cap  42 , which causes ink tank  38 - 1  to slide rearward, to move and firmly seat rib  86 - 1  of rear wall  80 - 1  of ink tank  38 - 1  into slot  90  of pivot mechanism  88  of printhead carrier  30 . The sliding action occurs before wick  54 - 1  contacts ink tank  38 - 1  so that wick  54 - 1  does not roll over. The front wall  78 - 1  of ink tank  38 - 1  slides along the rib feature provided by cantilever arm  60 - 1  as ink tank  38 - 1  is inserted. This causes ink tank  38 - 1  to have a mostly vertical motion in direction  94  (e.g., perpendicular to the upper surface of wick  54 - 1 ) as ink tank  38 - 1  comes into contact with wick  54 - 1 . This reduces any scrubbing action of ink tank  38 - 1  against wick  54 - 1  and reduces the possibility of wick  54 - 1  buckling and deforming. 
     When ink tank  38 - 1  is pushed in direction  94  a sufficient distance for latching tab  84 - 1  extending outwardly from an upper portion of front wall  78  of ink tank  38 - 1  to engage the opening of latch feature  66 - 1 , cantilever arm  60 - 1  springs back in direction  98 . In turn, latching tab  84 - 1  of ink tank  38 - 1  is received in the opening of latch feature  66 - 1 . When the pressure exerted in direction  94  is relieved, the associated spring  92  supplies an upward force in direction  100 , wherein latching tab  84 - 1  firmly engages latch surface  68 - 1  of latch feature  66 - 1 , and ink tank  38 - 1  is latched in the installed position. 
     This process described above with respect to  FIG. 5  is similar for each of monochrome ink tank  38 - 1  and color ink tanks  38 - 2 ,  38 - 3 ,  38 - 4 . 
       FIG. 6  illustrates the removal of an ink tank, with ink tank  38 - 1  being used as an example. This process described with respect to  FIG. 6  is similar for each of monochrome ink tank  38 - 1  and color ink tanks  38 - 2 ,  38 - 3 ,  38 - 4 . 
     To remove ink tank  38 - 1 , the user applies a force in direction  96  to the distal end  64  of cantilever arm  60 - 1 , until latching tab  84 - 1  of ink tank  38 - 1  is no longer engaged with the opening of latch feature  66 - 1  of cantilever arm  60 - 1 . At this time, the associated spring  92  causes a displacement of the front end of ink tank  38 - 1  in direction  100  to the position illustrated in  FIG. 4 , whereby exposing at least a portion of the sidewall structure  72 - 1  of ink tank  38 - 1 . The exposed portion of the sidewall structure  72 - 1  of ink tank  38 - 1  then may be grasped by a user to rotate ink tank  38 - 1  out of printhead carrier  30 . 
     While this invention has been described with respect to embodiments of the invention, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.