Low force ink jet printhead capping system

Information

  • Patent Grant
  • 6517185
  • Patent Number
    6,517,185
  • Date Filed
    Friday, March 9, 2001
    23 years ago
  • Date Issued
    Tuesday, February 11, 2003
    21 years ago
Abstract
A printhead capping system for capping a printhead includes a printhead cap having a plurality of adjoining walls. The plurality of adjoining walls has a proximal end and a distal end. The plurality of adjoining walls defines an interior region. A lip portion is provided having a perimetrical sealing surface. The lip portion extends from the distal end of the plurality of adjoining walls in a cantilever manner in, a direction non-orthogonal to an extent of the plurality of adjoining walls. In cross-section the lip portion tapers in a direction from the distal end toward the perimetrical sealing surface.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to an ink jet printer, and, more particularly, to a low force ink jet printhead capping system for an ink jet printer.




2. Description of the Related Art




Ink jet printers form an image on a print medium by selectively ejecting ink from one or more of a plurality of ink jet nozzles formed in a nozzle plate of an ink jet printhead. In order to maintain the printhead at an acceptable level of performance, ink jet printers typically include a maintenance station for performing scheduled maintenance operations and for providing a sealed environment for the printhead nozzle plate during periods of non-use.




One example of a maintenance station includes a movable maintenance sled including a printhead wiper and a printhead cap. The printhead wiper includes a blade edge for engaging the printhead nozzle plate to remove waste ink and contaminants that have accumulated on the printhead nozzle plate during printing. The cap may used to provide a sealed environment around the ink jet nozzles.




The cap is typically formed as a generally rectangular structure defined by four adjoining walls that extend vertically upwardly from a base, and is made from an elastomer. Commonly, the elastomer cap is placed over the nozzle plate of the printhead to ensure a sufficiently humid environment to avoid undesirable dried ink formation that may plug ink jet nozzles. Such a cap forms a leak-free seal between the printhead nozzles and the ambient environment. Conventionally, this has been done in one of two ways: by forcing the elastomer cap into the printhead with enough force to deform the cap around its sealing lip, or by providing a spring-loaded gimbaling mechanism behind the cap to allow the lip of the cap to “float” with the printhead. The former typically requires large forces to produce sufficient deformation to ensure a reliable seal, due to manufacturing tolerances. The latter typically requires less force, but adds a significant number of parts, thus increasing the cost and complexity of the cap mechanism.




As ink jet printing technology has evolved, the size of the ink jet printheads has been decreasing, while the size of the nozzle plate and the number of ink jet nozzles in the nozzle plate has increased. As a result, the surface area on the printhead available for establishing an effective seal with the cap has diminished. Also, with the larger-sized nozzle plates and the advent of non-planar printhead topography in the regions surrounding the nozzle plate, the amount of capping force exerted by the maintenance sled has had to increase to effect the same degree of sealing.




What is needed in the art is a printhead capping system that can reduce the amount of capping force required to establish and maintain an effective seal around the printhead nozzle plate.




SUMMARY OF THE INVENTION




The present invention provides a printhead capping system that can reduce the amount of capping force required to establish and maintain an effective seal around the printhead nozzle plate.




The invention comprises, in one form thereof, a printhead capping system including a printhead cap having a plurality of adjoining walls. The plurality of adjoining walls has a proximal end and a distal end. The plurality of adjoining walls defines an interior region. A lip portion is provided having a perimetrical sealing surface. The lip portion extends from the distal end of the plurality of adjoining walls in a cantilever manner in a direction non-orthogonal to an extent of the plurality of adjoining walls. In cross-section the lip portion tapers in a direction from the distal end toward the perimetrical sealing surface.




One advantage of the capping system of the present invention is that the printhead cap includes a high compliance sealing lip, which thereby lowers the capping force required to obtain an adequate seal between the printhead and the printhead cap.











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 partial perspective view of an ink jet printer embodying the present invention.





FIG. 2

is a bottom plan view of ink jet printhead cartridges used with the ink jet printer of FIG.


1


.





FIG. 3A

is an exploded view of a first embodiment of a printhead capping system of the present invention.

FIG. 3B

is a top plan view of a printhead cap of FIG.


3


A.





FIG. 4A

is a sectional view of an assembled printhead capping system of

FIG. 3A

taken along line


4


A—


4


A.

FIG. 4B

is an enlargement of a portion of the sectional view of

FIG. 4A

depicting a cross-section of a tapered linear portion of the printhead cap.

FIG. 4C

is a sectional view of a corner portion of the assembled printhead capping system of

FIG. 3A

taken along line


4


C—


4


C depicting a cross-section of a rounded tapered portion of the printhead cap.





FIG. 5

is a perspective view of a second embodiment of a printhead capping system of the present invention.





FIG. 6

is a sectional view of the printhead capping system of

FIG. 5

taken along line


6





6


of FIG.


5


.











Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate preferred embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.




DETAILED DESCRIPTION OF THE INVENTION




Referring to

FIG. 1

, there is shown a portion of an exemplary imaging apparatus in the form of an ink jet printer


10


that embodies the present invention. Ink jet printer


10


includes a frame


11


and a pair of removable ink printhead cartridges


12


and


14


supported by a printhead carrier


16


. While two printhead cartridges are shown, it should be understood that the present invention may be adapted to accommodate any number of cartridges. For example, in an ink jet printer commonly referred to as a “head swapper,” only one printhead cartridge is accommodated by the printer at a time, wherein a color cartridge and a black cartridge are interchanged during CMYK printing.





FIG. 2

shows a bottom view of each of printhead cartridges


12


and


14


. Printhead cartridge


12


includes a printhead


18


mounting an ink jet nozzle plate


20


having a plurality of ink jet nozzles


22


, shown as two columns of dots. Printhead cartridge


14


includes a printhead


24


mounting an ink jet nozzle plate


26


having a plurality of ink jet nozzles


28


, shown as two columns of dots. Each nozzle plate


20


,


26


includes a heater chip (not shown) having a plurality of jetting actuators positioned to form a one-for-one correspondence with the plurality of ink jet nozzles


22


,


28


. The jetting actuators are selectively energized to expel ink from corresponding ones of ink jet nozzles


22


,


28


to form an image on a media sheet


30


(see

FIG. 1

) in manner well known in the art. Sheet


30


may be, for example, paper, cloth or a plastic.




Carrier


16


is driven longitudinally in opposite directions, as indicated by double-headed arrow


31


, in a reciprocating fashion along a guide rod


32


. Guide rod


32


is supported at its opposing ends by frame


11


. Carrier


16


may be driven from any suitable power source (not shown) such as, for example, a motor and gear train, or pulley and belt drive mechanism, that is coupled with carrier


16


to cause carrier


16


to slide along guide rod


32


in a reciprocating manner in response to a rotation direction of the motor, as is well known in the art.




A maintenance station


34


is provided for performing printhead maintenance operations on the ink jet nozzles


22


,


28


of the printheads


18


,


24


, respectively. Such operations include, for example, a printhead spit maintenance operation, a printhead wiping operation and a printhead capping operation. Other services, such as for example, printhead priming and suction, may also be performed if desired, by the inclusion of a vacuum device (not shown) of the type well known in the art.




Maintenance station


34


includes a fixed support housing


36


, which is attached to frame


11


. A movable sled


38


is removably supported within a rectangular-shaped cavity


40


in support housing


36


and is adapted for both longitudinal and vertical movement therein. Mounted to sled


38


is a first printhead wiper


42


, a second printhead wiper


44


, a first printhead capping system


46


and a second printhead capping system


48


.




Support housing


36


includes a first housing wall


50


and a second housing wall


52


. First housing wall


50


has a pair of cam slots


54


and


56


formed therein at opposite ends thereof, and a second housing wall


52


has a cam slot


58


and an open cam surface


60


formed therein at opposite ends thereof




Movable sled


38


includes a carrier engagement member


62


, a first pair of pins


64


positioned symmetrically on opposite sides of sled


38


and extending therefrom, and a second pair of pins


66


positioned symmetrically on opposite sides of sled


38


and extending therefrom. Pins


64


are disposed in cam slots


54


,


58


, respectively, and pins


66


are disposed in cam slot


58


and on open cam surface


60


, respectively. Accordingly, each of pins


64


and


66


functions as a cam follower. Cam slot


54


, cam slot


56


, cam slot


58


and open cam surface


60


(collectively referred to as cams


54


,


56


,


58


,


60


) control vertical motion of the movable sled


38


during the longitudinal movement of sled


38


, based on the cam profile of cams


54


,


56


,


58


,


60


.




Sled


38


is spring biased in a direction toward carrier


16


. As can be seen in

FIG. 1

with reference to

FIG. 2

, a rightward movement of carrier


16


causes carrier


16


to engage carrier engagement member


62


, thereby causing movable sled


38


to move to the right, and pins


64


,


66


ride up the cam surface profile defined by cams


54


,


56


,


58


,


60


. When sled


38


reaches a first plateau defined by cams


54


,


56


,


58


,


60


, printhead wipers


42


,


44


are positioned at a height to perform wiping maintenance on respective ones of printhead nozzle plates


20


,


26


. When sled


38


is moved a second plateau defined by cams


54


,


56


,


58


,


60


, printhead capping systems


46


and


48


have fully engaged the printheads


18


,


24


of the ink cartridges


12


and


14


, respectively, thereby providing a seal around the areas containing nozzle plates


20


,


26


and the associated ink jet nozzles


22


,


28


, respectively. As printhead capping systems


46


,


48


initially come into contact with printheads


18


,


24


, a capping force (Fc) is required to continue to move printhead capping systems


46


and


48


upwardly into a sealing relationship with the printheads


18


,


24


of the printhead cartridges


12


,


14


. However, each of the printhead capping systems


46


and


48


is designed to reduce the capping force over that required to seal a printhead using a typical prior art rectangular elastomer printhead cap.




In the embodiment shown in

FIG. 1

, each of printhead capping systems


46


and


48


are virtually identical. Accordingly, for the sake of brevity, the following detailed discussion is directed to the structure of printhead capping system


46


. However, it is to be understood that any discussion that follows relating to the structure of printhead capping system


46


would also apply to the structure of printhead capping system


48


.





FIG. 3A

is an exploded view of printhead capping system


46


including a cap holder


68


and low force elastomer printhead cap


70


, shown in relation to printhead


18


of printhead cartridge


12


. A sealing surface


72


(also shown in

FIG. 4A

) on printhead


18


surrounding nozzle plate


20


is shown in FIG.


2


.

FIG. 3B

is a top plan view of printhead cap


70


.




Printhead cap


70


is a unitary cup-like structure made of an elastomer material. Printhead cap


70


includes a floor portion


74


, a plurality of adjoining walls


76


,


78


,


80


and


82


, a plurality of mounting tabs referred to collectively as tabs


84


, and a lip portion


86


. The plurality of adjoining walls


76


,


78


,


80


,


82


have a proximal end


88


and a distal end


90


. Proximal end


88


is coupled to a perimeter


92


of floor portion


74


and distal end


90


is spaced from floor portion


74


. Walls


76


,


78


,


80


,


82


define an interior region


94


.




Lip portion


86


is coupled to distal end


90


of the plurality of adjoining walls


76


,


78


,


80


,


82


. Lip portion


86


extends from the plurality of adjoining walls


76


,


78


,


80


,


82


at a perimeter


96


in a cantilever manner in a direction, depicted by arrow


98


, at an angle


100


that is non-orthogonal to a direction of an extent of the plurality of adjoining walls


76


,


78


,


80


,


82


, as depicted by arrow


102


. Lip portion


86


has a perimetrical sealing surface


104


.





FIG. 4A

shows a cross-section of printhead cap


70


taken along a line


4


A—


4


A of FIG.


3


A.

FIG. 4B

is an enlargement of a portion of the cross-section of FIG.


4


A.

FIG. 4C

is an enlargement of a rounded corner cross-section taken along line


4


C—


4


C of FIG.


3


A.




As shown in FIGS.


3


A and


4


A—


4


C, cantilevered lip portion


86


tapers at a shallow angle in a direction from distal end


90


of walls


76


,


78


,


80


,


82


toward perimetrical sealing surface


104


. As can be best seen in relation to

FIG. 3B

, lip portion


86


includes a first linear tapered portion


106


, a second linear tapered portion


108


, a third linear tapered portion


110


and a fourth linear tapered portion


112


arranged in a substantially rectangular configuration. A first rounded tapered portion


114


is positioned between the first and second linear tapered portions


106


,


108


. A second rounded tapered portion


116


is positioned between the second and third linear tapered portions


108


,


110


. A third rounded tapered portion


118


is positioned between the third and fourth linear tapered portions


110


,


112


. A fourth rounded tapered portion


120


is positioned between the first and fourth linear tapered portions


106


,


112


. This tapered cantilevered design advantageously gives lip portion


86


a high compliance characteristic, thereby reducing the required capping force.




Preferably, each of the first, second, third and fourth linear tapered portions


106


,


108


,


110


,


112


has a first cross-sectional area and each of the first, second, third and fourth rounded tapered portions


114


,


116


,


118


,


120


has a second cross-sectional area, wherein the second cross-sectional area of the rounded tapered portions


114


,


116


,


118


,


120


is less than the first cross-sectional area of the first, second, third and fourth linear tapered portions


106


,


108


,


110


,


112


, as shown by comparison of

FIG. 4B

with FIG.


4


C. Also, by comparison of

FIG. 4B

to

FIG. 4C

, dimension D


1


of

FIG. 4C

is less than dimension D


2


of

FIG. 4B

, i.e., first, second, third and fourth rounded tapered portions


114


,


116


,


118


,


120


are thinner than first, second, third and fourth linear tapered portions


106


,


108


,


110


,


112


.




As can be best seen in

FIG. 3B

, each rounded tapered corner portion


114


,


116


,


118


,


120


is defined by a first curve delimiter


122


, a second curve delimiter


124


and a middle curve portion


126


located between first curve delimiter


122


and second curve delimiter


124


. The second cross-sectional area of each rounded tapered corner portion


114


,


116


,


118


,


120


thins from each of the first and second curve delimiters


122


,


124


(where the first cross-sectional area ends) toward a middle curve portion, depicted by a line


126


, where the cross-sectional area is the thinnest and has the smallest cross-sectional area. The purpose of making the cantilevered lip portion


86


thinner at the corners is to even the pressure exerted by the contact of perimetrical sealing surface


104


with sealing surface


72


of printhead


18


.




Referring to

FIGS. 3A and 4A

, cap holder


68


is made of a rigid material, such as plastic, and defines a rigid structure having a base


128


, a wall section


130


and a cantilever portion


132


. A plurality of mounting members


134


extend away from base


128


, and are used to connect cap holder


68


to sled


38


. When printhead cap


70


is seated in cap holder


68


, cantilever portion


132


of cap holder


68


surrounds and is spaced away from lip portion


86


of printhead cap


70


. Thus, with reference to

FIGS. 4A

,


4


B and


4


C, when printhead cap


70


is not in contact with printhead


18


, an outer surface


136


of lip portion


86


does not contact the rigid cantilever portion


132


. However, when printhead cap


70


is in a state of compression by virtue of contact of perimetrical sealing surface


104


of printhead cap


70


with sealing surface


72


of printhead


18


, outer surface


136


of lip portion


86


contacts rigid cantilever portion


132


, such that cantilever portion


132


limits the amount of deflection of lip portion


86


.




Referring to

FIGS. 3A and 4A

, base


128


of cap holder


68


defines a vent path


138


formed as a serpentine groove therein. Also, a plurality of mounting slots


140


are provided in wall section


130


near base


128


. When printhead cap


70


is received into cap holder


68


, tabs


84


of printhead cap


70


are received into mounting slots


140


to hold printhead cap


70


in proper relationship to cap holder


68


. In addition, a vent hole


142


(see

FIG. 3B

) formed in printhead cap


70


is located to be in fluid communication with vent path


138


in cap holder


68


. Thus, vent path


138


and vent hole


142


facilitate fluid communication of interior region


94


with the atmosphere when printhead cap


70


and printhead


18


are in sealing engagement.




While the embodiment described herein uses a tab/slot arrangement for mounting printhead cap


70


to cap holder


68


, those skilled in the art will recognize that other attachment methods, such as using fasteners or adhesives, may be used to effect the attachment.




Thus, the capping system of the present invention provides a printhead cap


70


having a high compliance sealing lip portion


86


, which thereby lowers the capping force (Fc) required to obtain an adequate seal between printhead


18


and printhead cap


70


. Traditional cap systems typically need 150 grams to 300 grams of capping force to obtain adequate compliance and sealing of a printhead. In contrast, the capping system of the present invention permits effective sealing with about 100 grams or less of capping force. By using a thin cantilever section for sealing lip portion


86


, printhead cap


70


is kept to a minimum size and does not extend outside the area of sealing surface


72


of printhead


18


. This space economy allows for multiple printheads to be spaced close to one another.





FIGS. 5 and 6

are directed to a second embodiment of the present invention in which a capping system


146


is shown that is suitable for use in applying suction to a printhead


150


via a vacuum system (not shown) of ink jet printer


10


.




As can be best seen in

FIG. 6

, a printhead


150


includes a nozzle plate


152


, a plurality of standoff members


154


and a sealing region


156


that surrounds nozzle plate


152


. Referring again to

FIG. 5

, printhead


150


includes a plurality of guide channels


158


and


160


located at an outer wall


162


of printhead


150


. Guide channels


158


,


160


are positioned precisely with respect to nozzle plate


152


and the allotted sealing region


156


.




Printhead capping system


146


includes a cap holder


164


and a low force elastomer printhead cap


166


.




Referring to

FIGS. 5 and 6

, cap holder


164


includes a base


168


, a pair of cap mounting walls


170


,


172


, a pair of alignment arms


174


,


176


and a pair of stop posts


178


,


180


. Referring to

FIG. 6

, cap mounting walls


170


,


172


extend upwardly from a central portion


182


of base


168


. As shown in

FIG. 5

, alignment arms


174


,


176


are positioned in a spaced apart relationship and extend upwardly from a first end


184


of base


168


. Alignment arm


174


includes angled surfaces


174




a


and


174




b


, and alignment arm


176


includes angled surfaces


176




a


and


176




b


. A spring


188


is provided to apply a biasing spring force midway between alignment arms


174


and


176


. Stop posts


178


,


180


are positioned in a spaced apart relationship and extend upwardly from a second end


186


of base


168


.




Printhead cap


166


is a unitary cup-like structure made of an elastomer material. Printhead cap


166


includes a plurality of adjoining walls


192


and a lip portion


194


. The plurality of adjoining walls


192


is arranged as a substantially rectangular structure. The plurality of adjoining walls


192


defines a ledge


196


adjacent an interior region


198


, and a pair of mounting slots


200


,


202


. The plurality of adjoining walls


192


has a proximal end


204


and a distal end


206


.




Referring to

FIG. 6

, lip portion


194


is coupled to distal end


206


of adjoining walls


192


. Lip portion


194


extends from the adjoining walls


192


at a perimeter


208


in a cantilever manner in a direction depicted by arrow


210


, and at an angle


212


that is non-orthogonal to a direction of an extent, depicted by arrow


214


, of the plurality of adjacent walls


192


. Lip portion


194


has a perimetrical sealing surface


216


. Lip portion


194


has a substantially triangular cross-section that tapers at a shallow angle in a direction from distal end


206


of walls


192


toward perimetrical sealing surface


216


of lip portion


194


.




Ledge


196


has an extent in the direction indicated by


214


that is less than an extent of lip portion


194


in direction


214


, and a trough


218


is formed between ledge


196


and lip portion


194


.




Printhead cap


166


is installed on cap holder


164


by sliding printhead cap


166


over mounting walls


170


,


172


of cap holder


164


, such that mounting walls


170


,


172


are received in mounting slots


200


,


202


, respective, to form a compression fit. Alternatively, fasteners or adhesive could be used to hold printhead cap


166


to cap holder


164


.




During operation, cap holder


164


is lifted by sled


38


toward engagement with printhead


150


, and alignment arms


174


,


176


engage guide channels


158


,


160


, respectively, of printhead


150


. Alignment arm


174


, including angled surfaces


174




a


and


174




b


, and alignment arm


176


, including angled surfaces


176




a


and


176




b


, combine to provide for left to right and front to rear alignment of printhead cap


166


with printhead


150


, thereby restricting at least three degrees of freedom of movement of cap holder


164


with respect to printhead


150


. The terms left, right, front and rear are used in conjunction with the orientation of printhead capping system


146


and printhead


150


as shown in FIG.


5


. Spring


188


is provided to aid in establishing rotational and front to rear alignment of printhead cap


166


with printhead


150


. The bias spring force is applied midway between the alignment arms


174


,


176


. The action of this spring force keeps alignment arms


174


,


176


biased against guide channels


158


,


160


, respectively, of printhead


150


. As printhead cap


166


continues to rise, perimetrical sealing surface


216


of lip portion


194


of printhead cap


166


makes contact with sealing region


156


on printhead


150


. Thereafter, lip portion


194


deflects with the application of the capping force (Fc) applied by sled


38


. To prevent over-compression of printhead cap


166


, stop posts


178


,


180


contact the face


190


of printhead


150


. Stop posts


178


,


180


also prevent printhead cap


166


from cocking or tilting left to right.




The cross-sectional geometry of lip portion


194


provides for high compliance and a low capping force for a given displacement of lip portion


194


. With this geometry, sealing between printhead


150


and printhead cap


166


can be achieved with the application of a capping force (Fc) of 100 grams or less. This is a significant reduction over the capping force of 150 grams to 300 grams required for capping in the prior art to accomplish a seal on an equivalent capping area.




During an ink jet nozzle priming or suctioning operation, vacuum is applied to interior region


198


of printhead cap


166


. A normal high compliance cap would collapse with application of vacuum. To solve this problem, standoff members


154


of printhead


150


are provided to contact ledge


196


of printhead cap


166


with the application of vacuum to interior region


198


of printhead cap


166


. This prevents the collapse of lip portion


194


and/or the interior of printhead cap


166


with the application of vacuum.




While this invention has been described as having a preferred design, the present invention can 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.



Claims
  • 1. A printhead capping system for capping a printhead, comprising:a cap holder; and a printhead cap being mounted by said cap holder, said printhead cap including: a plurality of adjoining walls having a proximal end and a distal end, said plurality of adjoining walls defining an interior region; and a lip portion having a perimetrical sealing surface, said lip portion extending from said distal end of said plurality of adjoining walls in a cantilever manner in a direction non-orthogonal to an extent of said plurality of adjoining walls, wherein in cross-section said lip portion tapers in a direction from said distal end toward said perimetrical sealing surface.
  • 2. The printhead capping system of claim 1, wherein said lip portion has a first linear tapered portion and a first rounded tapered portion, said first linear tapered portion having a first cross-sectional area and said first rounded tapered portion having a second cross-sectional area, and wherein said second cross-sectional area is at least one of less than said first cross-sectional area and thinner than said first cross-sectional area.
  • 3. The printhead capping system of claim 1, wherein said lip portion comprises a plurality of linear tapered portions and a plurality of rounded tapered corner portions that together define a generally polygonal shape for said perimetrical sealing surface, and wherein at least one of said plurality of linear tapered portions has a first cross-sectional area and at least one of said plurality of rounded tapered corner portions has a second cross-sectional area, and wherein said second cross-sectional area is less than said first cross-sectional area.
  • 4. The printhead capping system of claim 3, wherein each rounded tapered corner portion is defined by a first curve delimiter, a second curve delimiter and a middle curve portion located between said first curve delimiter and said second curve delimiter, said second cross-sectional area of each rounded tapered corner portion thinning from each of said first curve delimiter and said second curve delimiter toward said middle curve portion.
  • 5. The printhead capping system of claim 1, wherein said lip portion includes:a first linear tapered portion, a second linear tapered portion, a third linear tapered portion and a fourth linear tapered portion arranged in a substantially rectangular configuration; and a first rounded tapered portion positioned between the first and second linear tapered portions, a second rounded tapered portion positioned between the second and third linear tapered portions, a third rounded tapered portion positioned between the third and fourth linear tapered portions and a fourth rounded tapered portion positioned between the first and fourth linear tapered portions, wherein at least one of the first, second, third and fourth linear tapered portions has a first cross-sectional area and at least one of the first, second, third and fourth rounded tapered portions has a second cross-sectional area, and wherein said second cross-sectional area is thinner than said first cross-sectional area.
  • 6. The printhead capping system of claim 5, wherein each of said first, second, third and fourth linear tapered portions has said first cross-sectional area and each of said first, second, third and fourth rounded tapered portions has said second cross-sectional area, and wherein said second cross-sectional area is less than said first cross-sectional area.
  • 7. The printhead capping system of claim 1, wherein said plurality of adjoining walls define a ledge adjacent said interior region, said ledge having an extent in a first direction which is less than an extent of said lip portion in said first direction, and wherein a trough is formed between said ledge and said lip portion.
  • 8. The printhead capping system of claim 7, wherein said printhead has a plurality of standoff members extending from said printhead toward said printhead cap, wherein said standoff members contact said ledge to prevent a collapse of said printhead cap.
  • 9. The printhead capping system of claim 1, wherein said cap holder includes a vent path formed therein, and wherein said printhead cap includes a floor portion coupled to said proximal end of said plurality of adjoining walls, said floor portion having an opening formed therein that is positioned to be in fluid communication with said vent path.
  • 10. The printhead capping system of claim 1, wherein said cap holder defines a rigid cantilevered structure positioned around of said printhead cap for limiting an amount of deflection of said lip portion when said perimetrical sealing surface contacts said printhead.
  • 11. The printhead capping system of claim 1, wherein said cap holder is formed from a rigid material, said cap holder defining a rigid cantilevered structure positioned around of said printhead cap, wherein when said printhead cap is not in contact with said printhead, an outer surface of said lip portion does not contact said rigid cantilever structure, and when said printhead cap is in a state of compression by virtue of contact with said printhead, said outer surface of said lip portion contacts said rigid cantilever structure to limit an amount of deflection of said lip portion.
  • 12. The printhead capping system of claim 11, wherein said cap holder includes a vent path formed therein, and wherein said printhead cap includes an opening positioned to be in fluid communication with said vent path.
  • 13. The printhead capping system of claim 1, wherein said cap holder includes a plurality of alignment arms for engaging a corresponding plurality of guide channels formed in said printhead for aligning said printhead cap with said printhead.
  • 14. The printhead capping system of claim 13, wherein said plurality of alignment arms restricts at least three degrees of freedom of movement of said cap holder with respect to said printhead.
  • 15. The printhead capping system of claim 13, wherein said cap holder includes a plurality of stop posts for engaging a face of said printhead to prevent over compression of said lip portion.
  • 16. A printhead cap for capping a printhead, comprising:a plurality of adjoining walls having a proximal end and a distal end, said plurality of adjoining walls defining an interior region; and a lip portion having a perimetrical sealing surface, said lip portion extending from said distal end of said plurality of adjoining walls in a cantilever manner in a direction non-orthogonal to an extent of said plurality of adjoining walls, wherein in cross-section said lip portion tapers in a direction from said distal end toward said perimetrical sealing surface.
  • 17. The printhead cap of claim 16, wherein said lip portion has a first linear tapered portion and a first rounded tapered portion, said first linear tapered portion having a first cross-sectional area and said first rounded tapered portion having a second cross-sectional area, and wherein said second cross-sectional area is at least one of less than said first cross-sectional area and thinner than said first cross-sectional area.
  • 18. The printhead cap of claim 16, wherein said lip portion comprises a plurality of linear tapered portions and a plurality of rounded tapered corner portions that together define a generally polygonal shape for said perimetrical sealing surface, and wherein at least one of said plurality of linear tapered portions has a first cross-sectional area and at least one of said plurality of rounded tapered corner portions has a second cross-sectional area, and wherein said second cross-sectional area is less than said first cross-sectional area.
  • 19. The printhead cap of claim 18, wherein each rounded tapered corner portion is defined by a first curve delimiter, a second curve delimiter and a middle curve portion located between said first curve delimiter and said second curve delimiter, said second cross-sectional area of each rounded tapered corner portion thinning from each of said first curve delimiter and said second curve delimiter toward said middle curve portion.
  • 20. The printhead cap of claim 16, wherein said lip portion includes:a first linear tapered portion, a second linear tapered portion, a third linear tapered portion and a fourth linear tapered portion arranged in a substantially rectangular configuration; and a first rounded tapered portion positioned between the first and second linear tapered portions, a second rounded tapered portion positioned between the second and third linear tapered portions, a third rounded tapered portion positioned between the third and fourth linear tapered portions and a fourth rounded tapered portion positioned between the first and fourth linear tapered portions, wherein at least one of the first, second, third and fourth linear tapered portions has a first cross-sectional area and at least one of the first, second, third and fourth rounded tapered portions has a second cross-sectional area, and wherein said second cross-sectional area is thinner than said first cross-sectional area.
  • 21. The printhead cap of claim 20, wherein each of said first, second, third and fourth linear tapered portions has said first cross-sectional area and each of said first, second, third and fourth rounded tapered portions has said second cross-sectional area, and wherein said second cross-sectional area is less than said first cross-sectional area.
  • 22. The printhead cap of claim 16, wherein said plurality of adjoining walls define a ledge adjacent said interior region, said ledge having an extent in a first direction which is less than an extent of said lip portion in said first direction, and wherein a trough is formed between said ledge and said lip portion.
  • 23. The printhead cap of claim 22, wherein said printhead has a plurality of standoff members extending from said printhead toward said printhead cap, wherein upon application of a vacuum to said interior region said standoff members contact said ledge to prevent a collapse of said printhead cap.
  • 24. The printhead cap of claim 16, wherein said printhead cap includes a floor portion coupled to said proximal end of said plurality of adjoining walls, said floor portion having a vent opening formed therein.
  • 25. An imaging apparatus, comprising:a frame; a printhead coupled to said frame for reciprocating movement in relation to said frame; and a printhead capping system coupled to said frame for capping said printhead, said printhead capping system having a cap holder and a printhead cap being mounted by said cap holder, said printhead cap including: a plurality of adjoining walls having a proximal end and a distal end, said plurality of adjoining walls defining an interior region; and a lip portion having a perimetrical sealing surface, said lip portion extending from said distal end of said plurality of adjoining walls in a cantilever manner in a direction non-orthogonal to an extent of said plurality of adjoining walls, wherein in cross-section said lip portion tapers in a direction from said distal end toward said perimetrical sealing surface.
  • 26. The imaging apparatus of claim 25, wherein said lip portion has a first linear tapered portion and a first rounded tapered portion, said first linear tapered portion having a first cross-sectional area and said first rounded tapered portion having a second cross-sectional area, and wherein said second cross-sectional area is at least one of less than said first cross-sectional area and thinner than said first cross-sectional area.
  • 27. The imaging apparatus of claim 25, wherein said lip portion comprises a plurality of linear tapered portions and a plurality of rounded tapered corner portions that together define a generally polygonal shape for said perimetrical sealing surface, and wherein at least one of said plurality of linear tapered portions has a first cross-sectional area and at least one of said plurality of rounded tapered corner portions has a second cross-sectional area, and wherein said second cross-sectional area is less than said first cross-sectional area.
  • 28. The imaging apparatus of claim 27, wherein each rounded tapered corner portion is defined by a first curve delimiter, a second curve delimiter and a middle curve portion located between said first curve delimiter and said second curve delimiter, said second cross-sectional area of each rounded tapered corner portion thinning from each of said first curve delimiter and said second curve delimiter toward said middle curve portion.
  • 29. The imaging apparatus of claim 25, wherein said lip portion includes:a first linear tapered portion, a second linear tapered portion, a third linear tapered portion and a fourth linear tapered portion arranged in a substantially rectangular configuration; and a first rounded tapered portion positioned between the first and second linear tapered portions, a second rounded tapered portion positioned between the second and third linear tapered portions, a third rounded tapered portion positioned between the third and fourth linear tapered portions and a fourth rounded tapered portion positioned between the first and fourth linear tapered portions, wherein at least one of the first, second, third and fourth linear tapered portions has a first cross-sectional area and at least one of the first, second, third and fourth rounded tapered portions has a second cross-sectional area, and wherein said second cross-sectional area is thinner than said first cross-sectional area.
  • 30. The imaging apparatus of claim 29, wherein each of said first, second, third and fourth linear tapered portions has said first cross-sectional area and each of said first, second, third and fourth rounded tapered portions has said second cross-sectional area, and wherein said second cross-sectional area is less than said first cross-sectional area.
  • 31. The imaging apparatus of claim of claim 25, wherein said plurality of adjoining walls define a ledge adjacent said interior region, said ledge having an extent in a first direction which is less than an extent of said lip portion in said first direction, and wherein a trough is formed between said ledge and said lip portion.
  • 32. The imaging apparatus of claim 31, wherein said printhead has a plurality of standoff members extending from said printhead toward said printhead cap, wherein upon application of a vacuum to said interior region said standoff members contact said ledge to prevent a collapse of said printhead cap.
  • 33. The imaging apparatus of claim 25, wherein said cap holder includes a vent path formed therein, and wherein said printhead cap includes a floor portion coupled to said proximal end of said plurality of adjoining walls, said floor portion having an opening formed therein that is positioned to be in fluid communication with said vent path.
  • 34. The imaging apparatus of claim 25, wherein said cap holder defines a rigid cantilevered structure positioned around of said printhead cap for limiting an amount of deflection of said lip portion when said perimetrical sealing surface contacts said printhead.
  • 35. The imaging apparatus of claim 25, wherein said cap holder is formed from a rigid material, said cap holder defining a rigid cantilevered structure positioned around of said printhead cap, wherein when said printhead cap is not in contact with said printhead, an outer surface of said lip portion does not contact said rigid cantilever structure, and when said printhead cap is in a state of compression by virtue of contact with said printhead, said outer surface of said lip portion contacts said rigid cantilever structure to limit an amount of deflection of said lip portion.
  • 36. The imaging apparatus of claim 35, wherein said cap holder includes a vent path formed therein, and wherein said printhead cap includes an opening positioned to be in fluid communication with said vent path.
  • 37. The imaging apparatus of claim 25, wherein said cap holder includes a plurality of alignment arms for engaging a corresponding plurality of guide channels formed in said printhead for aligning said printhead cap with said printhead.
  • 38. The imaging apparatus of claim 37, wherein said plurality of alignment arms restricts at least three degrees of freedom of movement of said cap holder with respect to said printhead.
  • 39. The imaging apparatus of claim 37, wherein said cap holder includes a plurality of stop posts for engaging a face of said printhead to prevent over compression of said lip portion.
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