Abstract:
A fluid ejection system includes a plurality of cartridges each including a fluid ejection device, and a carriage adapted to hold the cartridges. The carriage includes a carriage darn including a plurality of openings and a plurality of panels. Each of the openings accommodate one of the cartridges, and each of the panels have a surface oriented substantially parallel with a front face of the fluid ejection device  0 ° F. the one of the cartridges and at least one substantially straight edge extending substantially completely along a side of the one of the cartridges.

Description:
THE FIELD OF THE INVENTION 
     The present invention relates generally to inkjet printers, and more particularly to an inkjet printer including a carriage dam which controls the accumulation of the ink aerosol in the inkjet printer during printer. 
     BACKGROUND OF THE INVENTION 
     As illustrated in FIG. 1, a portion of a conventional inkjet printer  90  includes a printer carriage  91  and a plurality of print cartridges  92  installed in the printer carriage. Each print cartridge includes a printhead  93  which ejects or fires ink drops  94  through a plurality of orifices or nozzles  95  and toward a print medium  96 , such as a sheet of paper, so as to print a dot of ink on the print medium. Typically, the orifices are arranged in one or more columns or arrays such that properly sequenced ejection of ink from the orifices causes characters or other images to be printed upon the print medium as the print cartridge and the print medium are moved relative to each other. In one arrangement, the print medium is supported by a platen or roller  97  as the print cartridge traverses the print medium to create a band or swath of print on the print medium. 
     During printing, the ink drops generate a fine mist or fog of relatively small ink particles  98  suspended in air. Unfortunately, these small ink particles, referred to as ink aerosol, can accumulate on components of the inkjet printer and cause functional failures and/or cosmetic defects. The ink aerosol, for example, can cause corrosion of electrical contacts or traces of the print cartridges which, in turn, can lead to failure of the print cartridges. In addition, the ink aerosol can accumulate, for example, on the sides of the print cartridges such that when a user of the inkjet printer attempts to remove one or more of the print cartridges from the printer carriage, the accumulated ink aerosol is transferred onto the hands of the user thereby creating a messy operation. 
     The ink aerosol can also accumulate on media transport surfaces of the inkjet printer and be transferred to the print medium such that the print medium is marked or marred during printing. For example, when the printer carriage and print cartridges traverse the print medium during printing, the printer carriage may move beyond the edge of the print medium. As such, ink aerosol can accumulate on the platen or roller of the inkjet printer. Thus, when a subsequent sheet of print medium is routed through the inkjet printer, ink aerosol accumulated on the platen or roller may be transferred to the print medium. 
     Accordingly, a need exists for an inkjet printer which controls the accumulation of ink aerosol, generated during printing, on components of the inkjet printer. 
     SUMMARY OF THE INVENTION 
     One aspect of the present invention provides a fluid ejection system which includes a plurality of cartridges each including a fluid ejection device, and a carriage adapted to hold the cartridges. The carriage includes a carriage darn including a plurality of openings and a plurality of panels. Each of the openings accommodate one of the cartridges, and each of the panels have a surface oriented substantially parallel with a front bite of the fluid ejection device of the one of the cartridges and at least one substantially straight edge extending substantially completely along a side of the one of the cartridges. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side schematic view of a portion of a prior art inkjet printer; 
     FIG. 2 is a side schematic view of one embodiment of a portion of an inkjet printer including a carriage dam according to the present invention; 
     FIG. 3 is a bottom schematic view of the inkjet printer of FIG. 2; 
     FIG. 4 is a bottom perspective view of one embodiment of a carriage dam according to the present invention; 
     FIG. 5 is a top perspective view of the carriage dam of FIG. 4; and 
     FIG. 6 is a side schematic view of one embodiment of a portion of a service station assembly interacting with a portion of the carriage dam of FIG.  4 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “left,” “right,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. The inkjet printer and related components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. 
     FIGS. 2 and 3 illustrate one embodiment of a portion of an inkjet printer  10  for printing on a print medium  12 . Inkjet printer  10  includes a printer carriage  20  and a plurality print cartridges  30 . Print medium  12  includes a print region  14  within which print  16  in the form of characters and/or graphics is created as relative movement between print cartridges  30  and print medium  12  occurs during printing. Print medium  12  is any type of suitable material, such as paper, cardstock, transparencies, Mylar, and the like. 
     During printing, print medium  12  is held stationary as printer carriage  20  and print cartridges  30  move in a printing direction, as indicated by arrow  29 , to traverse print medium  12  and create print  16 . Upon completing a row of print  16 , print medium  12  is advanced in a direction substantially perpendicular to the printing direction indicated by arrow  29  (i.e., in and out of the plane of the paper). Thereafter, print medium  12  is held stationary as printer carriage  20  and print cartridges  30  move in a printing direction, as indicated by arrow  29 ′, opposite the printing direction indicated by arrow  29 , to traverse print medium  12  and create another row of print  16 . 
     Printer carriage  20  is slidably supported within a housing (not shown) of inkjet printer  10  for travel back and forth across print medium  12 , and print cartridges  30  are installed in printer carriage  20  for movement with printer carriage  20  during printing. Printer carriage  20 , including print cartridges  30 , has a scan axis  21  along which printer carriage  20  and, therefore, print cartridges  30  traverse during printing. 
     Print cartridges  30  each include a printhead  32  having a front face  34  in which a plurality of ink orifices or nozzles  36  are formed in a manner well known to those skilled in the art. It is understood that printhead  32  may include one or more columns or other arrays of ink orifices  36 . In one embodiment, ink orifices  36  of printhead  32  are arranged in one or more columns  37 . As such, each column  37  of ink orifices  36  is oriented substantially perpendicular to scan axis  21 . 
     Example embodiments of printhead  32  include a thermal printhead, a piezoelectric printhead, a flex-tensional printhead, or any other type of inkjet ejection device known in the art. If printhead  32  is, for example, a thermal printhead, printhead  32  typically includes a substrate layer (not shown) having a plurality of resistors (not shown) which are operatively associated with ink orifices  36 . Upon energization of the resistors, in response to command signals delivered by a controller (not shown) to a respective print cartridge  30 , drops of ink  38  are ejected through ink orifices  36  toward print medium  12 . 
     Print cartridges  30  may eject the same or differing colors of ink drops  38  during printing. In addition, all or less than all print cartridges  30  may be operated at one time. While inkjet printer  10  is illustrated as including four print cartridges  30 , it is within the scope of the present invention for inkjet printer  10  to include any number of print cartridges  30 . 
     Ink drops  38  are ejected through ink orifices  36  and from printhead  32  into a print zone  15  with an intended ink drop trajectory. Print zone  15  is defined as being between printhead  32  and print medium  12 , and encompasses ink drops  38 . As such, print zone  15 , as well as print region  14  of print medium  12 , move with print cartridges  30  during printing. In one embodiment, ink drops  38  generate ink aerosol  39  in the form of a fine mist or fog of relatively small ink particles suspended in air. It is understood that the representation of ink aerosol  39 , as illustrated in FIG. 1, for example, has been exaggerated for clarity of the invention. 
     Printer carriage  20  has a leading end  22  and a trailing end  24  when printer carriage  20  moves along scan axis  21  in the printing direction indicated by arrow  29  and a leading end  22 ′ and a trailing end  24 ′ when printer carriage  20  moves along scan axis  21  in the printing direction indicated by arrow  29 ′, opposite the printing direction indicated by arrow  29 . In addition, since print cartridges  30  and, therefore, printhead  32  are installed in printer carriage  20  for movement with printer carriage  20  during printing, scan axis  21  represents a scan axis of print cartridges  30 . 
     In one embodiment, printer carriage  20  includes a carriage shell  26  and a carriage dam  28 . Carriage shell  26  is configured to hold print cartridges  30  and is mounted in inkjet printer  10  for lateral movement relative to print medium  12 . As such, carriage shell  26  supports print cartridges  30  for movement back and forth across print medium  12 . Thus, carriage shell  26  and print cartridges  30  traverse print medium  12  along scan axis  21 . 
     Carriage dam  28  is joined to carriage shell  26  and extends between leading end  22  of printer carriage  20  and trailing end  24  of printer carriage  20 . In one embodiment, carriage dam  28  includes a plate  280  which extends between leading end  22  of printer carriage  20  and trailing end  24  of printer carriage  20 . In one embodiment, carriage dam  28  is formed integrally with carriage shell  26 . In another embodiment, however, carriage dam  28  is formed separately from carriage shell  26 . As such, carriage dam  28  is secured or attached to carriage shell  26  for movement with carriage shell  26  during printing. 
     Plate  280  has a plurality of openings  281  defined therein. Openings  281  are each sized and configured to accommodate one print cartridge  30  such that printhead  32  of a respective print cartridge  30  is accessible and/or extends through a respective opening  281 . Openings  281  are spaced laterally from each other along scan axis  21  such that carriage dam  28  includes a plurality of panels  282  each formed by a portion of plate  280  adjacent to one or more openings  281  in plate  280 . 
     Plate  280  and, more specifically, panels  282  form a surface  283  of carriage dam  28  which is oriented substantially parallel with front face  34  of printhead  32  of print cartridges  30  when print cartridges  30  are supported by carriage shell  26 . As such, surface  283  of carriage dam  28  is oriented substantially parallel with print region  14  of print medium  12  during printing. 
     Preferably, panels  282  of carriage dam  28  are each positioned laterally of and adjacent to print cartridges  30  when print cartridges  30  are supported by carriage shell  26 . As such, panels  282  are positioned and extend between adjacent print cartridges  30 . Panels  282  each have at least one edge  284  which is oriented substantially perpendicular to scan axis  21 . In addition, edge  284  of each panel  282  is oriented substantially parallel with column  37  of ink orifices  36  of adjacent print cartridges  30 . 
     In one embodiment, printer carriage  20  and, more specifically, carriage shell  26  supports and/or holds print cartridges  30  such that a gap  40  is formed between adjacent print cartridges  30 . As such, a pocket  42  is formed between adjacent print cartridges  30 . Preferably, panels  282  of carriage dam  28  substantially block gap  40  between adjacent print cartridges  30 . As such, pocket  42  between adjacent print cartridges  30  is substantially closed by carriage dam  28 . 
     During printing, as described above, printer carriage  20  and, therefore, print cartridges  30  traverse print medium  12  in the printing directions indicated by arrows  29  and  29 ′. As such, ink drops  38  are ejected from printhead  32  of one or more print cartridges  30 . As ink drops  38  are ejected during printing, ink aerosol  39  is generated. Thus, with carriage dam  28 , ink aerosol  39  accumulates on surface  283  of panels  282  of carriage dam  28 . Ink aerosol  39 , therefore, accumulates on carriage dam  28  rather than print cartridges  30 . 
     FIGS. 4 and 5 illustrate another embodiment of carriage dam  28 . Carriage dam  28 ′, similar to carriage dam  28 , accommodates a plurality of print cartridges  30  (only one of which is illustrated in the drawings). Reference herein to carriage dam  28 , therefore, is also applicable to carriage dam  28 ′. While carriage dam  28 ′ is illustrated as accommodating six print cartridges  30 , it is within the scope of the present invention for inkjet printer  10  to include any number of print cartridges  30  and, therefore, for carriage dam  28 ′ to accommodate any number of print cartridges  30 . 
     In one embodiment, carriage dam  28 ′ includes a pair of rails  285  which extend between leading end  22  of printer carriage  20  and trailing end  24  of printer carriage  20  when carriage dam  28 ′ is joined to carriage shell  26 . Rails  285  are spaced from each other in a direction substantially perpendicular to scan axis  21  of printer carriage  20 . As such, panels  282  of carriage dam  28 ′ extend between rails  285  and are spaced laterally from each other along scan axis  21  to form openings  281  which accommodate print cartridges  30 . Preferably, rails  285  are oriented substantially parallel with scan axis  21  of printer carriage  20 . In addition, panels  282  of carriage dam  28 ′ extend between rails  285  in a direction substantially perpendicular to scan axis  21 . 
     In one embodiment, as illustrated in FIG. 6, inkjet printer  10  includes a service station assembly  50 . Service station assembly  50 , as is known in the art, includes a rubber blade or wiper  52  which is periodically passed over printhead  32  of a respective print cartridge  30  to wipe and clean front face  34  and, therefore, ink orifices  36  of excess ink. Thus, with carriage dam  28 , wiper  52 , as illustrated in FIG. 6, may be periodically passed over a respective panel  282  of carriage dam  28  to wipe and clean surface  283  of panel  282  of ink aerosol  39 . 
     By providing printer carriage  20  with carriage dam  28 , carriage dam  28  controls the accumulation of ink aerosol  39  in inkjet printer  10 . More specifically, panels  282  of carriage dam  28  block gaps  40  between adjacent print cartridges  30  and close pockets  42  formed between adjacent print cartridges  30 . As such, ink aerosol  39  generated during printing accumulates on carriage dam  28  and, more specifically, panels  282  of carriage dam  28  rather than print cartridges  30 . Thus, wiper  52  of service station assembly  50  may be used to remove accumulated ink aerosol  39  from surface  283  of panels  282 . Surface  283  of panels  282 , therefore, provides a serviceable surface of carriage dam  28 . 
     By blocking gaps  40  between adjacent print cartridges  30 , carriage dam  28  reduces or eliminates the accumulation of ink aerosol  39  on, for example, the sides of print cartridges  30 . Thus, potential functional failures caused by the accumulation of ink aerosol on, for example, electrical contacts provided on the sides of print cartridges  30  are avoided. In addition, the mess created by the accumulation of ink aerosol on the sides of print cartridges  30  is avoided. Furthermore, by closing pockets  42  between adjacent print cartridges  30 , carriage dam  28  reduces an amount of free-floating ink aerosol  39  in inkjet printer  10  by reducing areas where ink aerosol  39  can drift. Thus, by providing carriage dam  28 , ink aerosol  39  accumulates on carriage dam  28  rather than floating freely within inkjet printer  10  and accumulating on other components of inkjet printer  10  such as a platen or roller of inkjet printer  10 . Carriage dam  28 , therefore, controls the accumulation of ink aerosol  39  in inkjet printer  10  during printing. 
     Although specific embodiments have been illustrated and described herein for purposes of description of the preferred embodiment, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent implementations calculated to achieve the same purposes may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. Those with skill in the chemical, mechanical, electromechanical, electrical, and computer arts will readily appreciate that the present invention may be implemented in a very wide variety of embodiments. This application is intended to cover any adaptations or variations of the preferred embodiments discussed herein. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.