Abstract:
Example embodiments disclosed herein relate to a printhead cap assembly. An example includes a rigid base member and a mount gimbaled with respect to the rigid base member and configured to define a recess including a side. The printhead cap assembly additionally includes a sealing member configured to include a retention feature positioned in the recess and engaging the side to orient and couple the sealing member to the mount so that the sealing member retains an original shape.

Description:
BACKGROUND 
       [0001]    A challenge exists to deliver quality and value to consumers, for example, by providing imaging devices such as inkjet printers that are cost effective. Additionally, businesses may desire to enhance the reliability of such imaging devices. Further, businesses may desire to improve the performance of one or more components of such imaging devices. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0002]    The following detailed description references the drawings, wherein: 
           [0003]      FIG. 1  shows a perspective view of an example of a printhead cap assembly. 
           [0004]      FIG. 2  shows an exploded perspective view of an example of a printhead cap assembly. 
           [0005]      FIG. 3  shows an example of a cross-sectional view of the printhead cap assembly of  FIG. 1  taken along line  3 - 3 . 
           [0006]      FIG. 4  shows an enlarged view of an example of a mounting flange or retention feature. 
           [0007]      FIG. 5  shows an example of a cross-sectional view of the printhead cap assembly of  FIG. 1  taken along line  5 - 5 . 
           [0008]      FIG. 6  shows an example of a cross-sectional view of the printhead cap assembly of  FIG. 1  taken along line  6 - 6 . 
           [0009]      FIG. 7  shows an example of a vent plug. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    Inkjet printing devices utilize a service station to help maintain the performance of inkjet printheads. One of the components of such service stations is a cap assembly that protects the printheads during periods of non-use. The cap assembly helps prevent debris from accumulating on the printheads, thereby keeping them clean. The cap assembly also seals the printheads to help prevent the nozzles of the printheads from drying out which can clog them. 
         [0011]    One of the components of such printhead cap assemblies is the sealing member which directly contacts the printheads. This sealing member is attached to a mount of the cap assembly. The means used to attach the sealing member to the mount should not distort it, otherwise the cap assembly may not adequately protect the printheads due to one or more gaps caused by such distortion. 
         [0012]    A perspective view of an example of a printhead cap assembly  10  is shown in  FIG. 1 . As can be seen in  FIG. 1 , printhead cap assembly  10  includes a rigid base member  12 , a mount  14 , and a sealing member  16 , each of which is discussed in more detail below. The example of printhead cap assembly  10  shown in  FIG. 1  is designed for a page-wide array of three printheads each with drop ejectors and nozzles (not shown), one of each of which is enclosed and capped by lip  182  of sealing member  16  at respective general locations  18 ,  20 , and  22 . Other embodiments of printhead cap assemblies in accordance with the present invention may be designed for more or less printheads (including a single printhead), linearly arranged, as illustrated, staggered, or side by side. 
         [0013]    An exploded perspective view of an example of printhead cap assembly  10  is shown in  FIG. 2 . As can be seen in  FIG. 2 , rigid base member  12  includes a stiffener  24  made from metal or plastic and a plate  26  disposed on stiffener  24  which may also be made from metal or plastic. The combination of stiffener  24  and plate  26  of base member  12  are designed to attach cap assembly  10  to a service station (not shown in  FIG. 2 ) of a printing device (also not shown in  FIG. 2 ) and also to provide support to the other components of cap assembly  10 . Stiffener  24  includes openings  28  and  30  on end  32  and openings  34  and  36  on end  38  through which fasteners (not shown) may be disposed into attachment features  40  and  42  on end  44  of plate  26  and attachment features  46  and  48  on end  50  of plate  26  to couple stiffener  24  to plate  26 . 
         [0014]    Bosses  52 ,  54 ,  56 , and  58  are formed on or attached to plate  26  on which respective biasing members  60 ,  62 ,  64 , and  66  are positioned. Although not shown in  FIG. 2 , similar bosses are formed on or attached to bottom side  68  of mount  14 . Mount  14  attaches to plate  26  via, pairs of side members  70 ,  72 ,  74 , and  76  each of which is formed to define a respective opening  78 ,  80 ,  82 , and  84  through which pairs of side tabs  86 ,  88 ,  90 , and  92  of plate  26  are respectively disposed. Although not shown in  FIG. 2 , it is to be understood that side  94  of plate  26  includes a set of side tabs  86 ,  88 ,  90 , and  92  that correspond to side tabs  86 ,  88 ,  90 , and  92  on side  96 . 
         [0015]    The above-described manner of attaching mount  14  to plate  26  allows side tabs  86 ,  88 ,  90 , and  92  to slide within openings  78 ,  80 ,  82 , and  84  as biasing members  60 ,  62 ,  64 , and  66  are compressed and relaxed. It also creates a gimbal assembly that permits mount  14  of cap assembly  10  to deflect and move freely upon engagement with one or more printheads that may not be perfectly aligned in all three axes while still maintaining an adequate seal around them. It additionally helps prevent damage to these printheads potentially caused by contact with cap assembly  10 . 
         [0016]    As can also be seen in  FIG. 2 , mount  14  is configured to include or define openings, recesses or cavities  98 ,  100 ,  102 ,  104 ,  106 , and  108  each of which includes a respective wall, side, or edge  110 ,  112 ,  114 ,  116 ,  118 , and  120 . As discussed more fully below, sealing member  16  is configured to include retention features or mounting flanges located on bottom  122  in the generally indicated positions  124 ,  126 ,  128 ,  130 ,  132 , and  134 . These retention features or mounting flanges are disposed or otherwise positioned in openings  98 ,  100 ,  102 ,  104 ,  106 , and  108  to orient or align and couple or attach sealing member  16  to mount  14 . 
         [0017]    As can be additionally seen in  FIG. 2 , an ambient vent  136  is formed in sealing member  16  and is configured to communicate with the ambient environment. A vent plug  138  is disposed or positioned in ambient vent  136 . Pads  140 ,  142 , and  144  are respectively disposed or positioned in respective wells  146 ,  148 , and  150  and secured therein by tabs  152 ,  154 ,  156 ,  158 ,  160 ,  162 ,  164 ,  166 ,  168 ,  170 ,  172 , and  174 , as shown in  FIG. 1 . Pads  140 ,  142 , and  144  are designed to absorb ink that may remain on capped printheads (not shown in  FIG. 1 ) after servicing or that may drool or drain from the nozzles thereof (also not shown in  FIG. 1 ) while the printheads are capped. 
         [0018]      FIG. 3  shows an example of a cross-sectional view of printhead cap assembly  10  taken along line  3 - 3  of  FIG. 1 . An outline of an exemplary printhead  176  has been added for illustration. Printhead  176  is part of printing device  178  which has also been added in  FIG. 3  for purposes of illustration. As can be seen in  FIG. 3  and discussed above, a boss  180  is formed on or attached to bottom side  68  of mount  14  around which biasing member  62  is positioned. Similar bosses (not shown in  FIG. 3 ) exist on bottom side  68  of mount  14  for biasing members  60  and  66 . 
         [0019]    As can be seen in  FIG. 3 , sealing member  16  of cap assembly  10  is configured to include a lip  182  that contacts face  184  of printhead  176  to complete the function of sealing the nozzles (not shown) thereof. Lip  182  may be made from an elastomeric material to facilitate such sealing and also to provide a certain amount of deflection or give upon contact with face  184  of printhead  176 . Further deflection is provided by biasing member  62  which is compressible. Openings  186  and  188  in stiffener  24  provide clearance for side members  72  during any such further deflection. Although not shown in  FIG. 3 , it is to be understood that similar openings in stiffener  24  may be provided for side members  70 ,  74 , and  76  (shown in  FIG. 2 ). 
         [0020]    As can further be seen in  FIG. 3 , sealing member  16  is configured to include a mounting flange or retention feature  190  located on bottom  122  at position  128  (see  FIG. 2 ). An enlarged view of mounting flange or retention feature  190  is shown in  FIG. 4 . As can be seen in  FIG. 4 , mounting flange or retention feature  190  is disposed or otherwise positioned in opening  102  of mount  14  to orient or align and couple or attach seating member  16  to mount  14 . Mounting flange or retention feature  190  includes a dart  192  which is designed to engage and grip wall  114  of mount  14  thereby attaching and accurately aligning sealing member  16  to mount  14 . Although not shown in  FIGS. 3 and 4 , it is to be understood that cap assembly  10  includes additional mounting flanges or retention features (like mounting flange or retention feature  190 ) located at generally indicated positions  124 ,  126 ,  130 ,  132 , and  134  (see  FIG. 2 ). 
         [0021]    A cross-sectional view of printhead cap assembly  10  taken along line  5 - 5  of  FIG. 1  is shown in  FIG. 5 .  FIG. 5  provides a different perspective of cap assembly  10  than that shown in  FIG. 3 . For example, tabs  152  and  156  are shown which are used to hold pad  140  within well  146 . As another example, portion  194  is shown rather than an opening, recess, or cavity for a retention feature or mounting flange. Portion  194  provides support for bottom  196  of seat member  16 . 
         [0022]    A cross-sectional view of printhead cap assembly  10  taken along line  6 - 6  of  FIG. 1  is shown in  FIG. 6 . As can be seen in  FIG. 6 , one end  198  of biasing member  64  is disposed on boss  56  and the other end  200  of biasing member  64  is positioned adjacent bottom side  68  of mount  14  within the cavity  202  defined by downwardly depending, generally cylindrical member  204 . Member  204  helps maintain lateral stability of biasing member  64 . 
         [0023]    As can also be seen in  FIG. 6  and as discussed above, ambient vent  136  is formed in sealing member  16 . Vent plug  138  is disposed or positioned in cavity, recess, or opening  206  defined by ambient vent  136 . Ambient vent  136  and vent plug  138  allow for gaseous communication with the ambient environment. As can further be seen in  FIG. 6 , ambient vent  136  is configured to include a retention feature or flange  208  that engages bottom side  68  of mount  14  to help secure sealing member  16  to mount  14 . Retention feature or flange  208  includes a dart in the example shown in  FIG. 6 . 
         [0024]      FIG. 7  shows an enlarged view of vent plug  138 . As can be seen in  FIG. 7 , vent plug  138  is configured to include a labyrinth channel  210 . Labyrinth channel  210  extends around circumference  212  of vent plug  138  in a spiraling or serpentine manner from end  214  to end  216 , as shown. Vent plug  138  helps prevent water vapor transmission from capped printheads to the ambient environment while labyrinth channel  210  allows a sufficient quantity of ambient air to flow to help compensate for barometric fluctuations, pressure changes due to temperature excursions, and pressure changes due to altitude excursions that may occur during transportation and general use. 
         [0025]    Although several examples have been described and illustrated in detail, it is to be clearly understood that the same are intended by way of illustration and example only. These examples are not intended to be exhaustive or to limit the invention to the precise form or to the exemplary embodiments disclosed. Modifications and variations may well be apparent to those of ordinary skill in the art. For example, although a single ambient vent  136  and vent plug  138  have been shown, other exemplary embodiments of the cap assembly of the present invention may include two or more such ambient vents and plugs. The spirit and scope of the present invention are to be limited only by the terms of the following claims. 
         [0026]    Additionally, reference to an element in the singular is not intended to mean one and only one, unless explicitly so stated, but rather means one or more. Moreover, no element or component is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.