WO2010087839A1

WO2010087839A1 - Print cartridge air discharge

Info

Publication number: WO2010087839A1
Application number: PCT/US2009/032506
Authority: WO
Inventors: P. Mark Haines
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2009-01-29
Filing date: 2009-01-29
Publication date: 2010-08-05

Abstract

A print cartridge (24, 224) discharges or vents air from a volume (72, 272) between a filter (46, 246) and a print head (42, 242).

Description

PRINT CARTRIDGE AIR DISCHARGE

BACKGROUND

[0001] Some print cartridges are factory filled with ink or liquids. While in the cartridge, the liquids or inks in the print cartridges may degrade components of the cartridge. During use, air built up within the cartridge may inhibit printing performance.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Figure 1 is a sectional view schematically illustrating a printing system including a print cartridge at a first point during filling of the print cartridge according to an example embodiment.

[00031 Figure 2 is a sectional view schematically illustrating the printing system oi^~

Figure 1 at a second point during filling of the print cartridge according to an example embodiment.

[0004] Figure 3 is a sectional view schematically illustrating the printing system of

Figure 1 during printing with the print cartridge according to an example embodiment.

[00051 Figure 4 is a sectional view schematically illustrating a valving system of (he print cartridge of Figure 1 in a closed position according to an example embodiment.

[0006] Figure 5 is a sectional view schematically illustrating a valving system of the print cartridge of Figure 1 in an open position according to an example embodiment.

10007] Figure 6 is a flow diagram of a method for filling the print cartridge of Figure I according to an example embodiment.

[0008] Figure 7 is a sectional view of an example embodiment of the printing system of

Figure I in a printing position according to an example embodiment.

[0009] Figure 8 is a top plan view of a lower half of a crown of a print cartridge of (he printing system oi^' Figure 7 according to an example embodiment. [0010] Figure 9 is a bottom plan view of the lower half of the crown of Figure 8 according to an example embodiment.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

[0011] Figures 1-5 schematically illustrate a printing system 20 according to an example embodiment. Priming system 20 includes a printer 22 and a print cartridge 24. In the example illustrated, print cartridge 24 is configured to be mounted in printer 22 in a vertical orientation for printing onto a print medium 26 supported in a vertical orientation. As will be described hereafter, print cartridge 24 is configured to be filled with liquid or ink while mounted within printer 22 in the same vertical orientation. During such filling, air is discharged or vented. In the particular embodiment illustrated, print cartridge 24 additionally provides an enlarged internal volume for storing or warehousing air during use of the print cartridge 24. As a result, print cartridge 24 may be shipped from the factory while empty, may be filled by an end-user and may provide enhanced printing performance.

[0012] Printer 22, schematically shown, supports print cartridge 24, services print cartridge 24 and positions print medium 26 relative to print cartridge 24 while print cartridge 24 is in a vertical orientation. For purposes of this disclosure, a print cartridge is in the "vertical orientation" when the print head(s) or nozzles of the print cartridge extend in a substantially vertical or inclined (greater than 45 degrees with respect to horizontal) plane. Printer 22 includes service station 28 (shown in Figures 1 and 2), media transport 30 (shown in Figure 3), dock 32, liquid source 34, air discharge 36 and controller 38.

[0013] Service station 28 comprises a part of printer 22 configured to service print cartridge 24. Service station 28 includes a capper 39 configured to cap or seal nozzles of one or more print heads of print cartridge 24. In one embodiment, print cartridge 24 is moved to a servicing position opposite to capper 39 which is stationary. In another embodiment, capper 39 is moved to a servicing position opposite to print cartridge 24. [0014] Media transport 30 (shown in Figure 3) comprises one or more devices are structured configured to transport, reposition or otherwise move print medium 26 and to support print medium 26 in a vertical orientation opposite to print cartridge 24. Media transport 30 may comprise one or more belts, rollers, movable trays and the like. [0015] Dock 32 comprises one more structures configured to mount and support print cartridge 24 substantially opposite to media transport 30 and opposite to print medium 26 being supported by media transport 30. In one embodiment, dock 32 comprises a substantially stationary structure. In another embodiment, dock 32 may be provided as part of a carriage that moves or scans across print medium 26 and across media transport 30. Although dock 32 is schematically illustrated as being mounted to print cartridge 24 on an underside of print cartridge 24, dock 32 may alternatively be mounted to or extend along multiple sides or faces of print cartridge 24 and may be mounted to print cartridge 24 on other sides of print cartridge 24. Dock 32 may have a variety of shapes, sizes and configurations.

[0016] Liquid source 34 comprises a source or supply of liquid for print cartridge 24. Liquid source 34 is provided as part of or is sufficiently close to printer 22 so as to be fluidly connected to print cartridge 24 while print cartridge 24 is mounted to dock 32. In other embodiments, liquid source 34 may be separate from printer 22 such as a separate fill station that may be operated by a retailer or an end-user of print cartridge 24, wherein the retailer or end-user receives an empty print cartridge 24 from a manufacturer, distributor or wholesaler.

[0017] In one embodiment, liquid source 34 supplies liquid ink to print cartridge 24. In particular embodiment, the ink supplied by liquid source 34 may contain methyl ethyl ketone (MEK), acetone, ethel acetate and alcohols. In other embodiments, liquid source 34 may deliver other liquids for printing to cartridge 24. In some embodiments, liquid source 34 is in communication with controller 38 and supplies liquid to cartridge 24 under the control of controller 38.

[0018] Air discharge 36 comprises a device configured to receive air removed or discharged from print cartridge 24. In one embodiment, air discharge 36 may be additionally configured to supply pressurized air to print cartridge 24. In one embodiment, air discharge 36 is provided as part of or is sufficiently close to printer 22 so as to be pneumatically connected to print cartridge 24 while print cartridge 24 is mounted to dock 32. In other embodiments, liquid source 34 may be separate from printer 22 such as a separate fill station that may be operated by a retailer or an end-user of print cartridge 24, wherein the retailer or end-user receives an empty print cartridge 24 from a manufacturer, distributor or wholesaler.

[0019] In one embodiment, air discharge 36 stores or warehouses the received air which may contain contaminants or volatiles. In one embodiment, air discharge 36 may filter received air prior to storage or prior to discharge to atmosphere. In one embodiment, air discharge 36 may include a vacuum source to assist in withdrawing air from print cartridge 24. In j^et other embodiments, air discharge 36 may be omitted, wherein air discharge from print cartridge 24 is released directly to atmosphere. [0020J Controller 38 comprises one or more processing units configured to generate control signals at least directing the filling of print cartridge 24. In one embodiment, controller 38 is further configured to generate control signals directing priming of print cartridge 24, printing by print cartridge 24 and/or the positioning of print medium 26 by media transport 30. Controller 38 may communicate with various components of print cartridge 24 and/or media transport 30 and a wired fashion or in a wireless fashion. [0021] For purposes of this application, the term "processing unit" shall mean a presently developed or future developed processing unit that executes sequences of instructions contained in a memory. Execution of the sequences of instructions causes the processing unit to perform steps such as generating control signals. The instructions may be loaded in a random access memory (RAM) for execution by the processing unit from a read only memory (ROM), a mass storage device, or some other persistent storage. In other embodiments, hard wired circuitry may be used in place of or in combination with software instructions to implement the functions described. For example, controller 38 may be embodied as part of one or more application-specific integrated circuits (ASICs). Unless otherwise specifically noted, the controller is not limited to any specific combination of hardware circuitry and software, nor to any particular source for the ins tractions executed by the processing unit. [0022] Print cartridge 24 comprises body 40, print head 42, lower chamber 44, filter 46, upper chamber 48, liquid supply passage 50, air discharge passage 52, air bypass passage 54, vent passage 56, sensor 58 and valve systems 62, 64 (schematically illustrated). Body 40 comprises one or more structures which cooperate to form or enclose the remaining components of cartridge 24. In particular, body 40 forms lower chamber 44, upper chamber 48, liquid supply passage 50, air discharge passage 52, air bypass passage 54, vent passage 56. Body 40 supports and encloses print head 42, filter 46, sensor 58 and valve systems 62, 64. Although body 40 is schematically illustrated as a single piece, body 40 may alternatively be formed from multiple members bonded, welded, fastened or otherwise joined to one anoiher.

[0023] Print head 42 comprises one or more print heads having nozzles 68 through which liquid is selectively ejected or discharged. In one embodiment, print head 42 may comprise one or more therm oresistive inkjet print heads. In another embodiment, print head 42 may comprise one or more piezo resistive inkjet print heads. In other embodiments, print head 42 may comprise other types of print heads configured to selectively eject liquid.

[0024] As shown by Figure 3, print head 42 is mounted to and supported by body 40 so as to extend in a substantially vertical orientation when print cartridge 24 is mounted to dock 32 and when print cartridge 24 is ejecting liquid onto print medium 26 positioned by printer 22. In the particular example illustrated, print head 42 is supported by body 40 so as to extend in a vertical plane (90° from horizontal) when print cartridge 24 is mounted to dock 32. In other embodiments, printhead 42 may be supported by body 40 in other vertical orientations. For example, in other embodiments, cartridge 24 (also known as a pen) may be oriented to fire drops downward in the vertical plane. The cartridge 24 and print head 42 will also work rotated up to 45 degrees upward. [0025] Lower chamber 44 extends opposite to print head 42. Lower chamber 44 is located at a lower end of print cartridge 24, below upper chamber 48, when print cartridge 24 is mounted or docked to dock 32. Lower chamber 44 includes volumes 70 and 72 which are separated from one another by filter 46. Volume 70 receives liquid from liquid source 34 through liquid supply passage 50. Volume 72 extends adjacent to print heads 42 and receives liquid from volume 70 after the liquid has passed through filter 46. Filter 46 filters such liquid prior to the liquid being presented to print heads 42. [0026] Upper chamber 48 is located at an upper end of print cartridge 24, above lower chamber 44. Upper chamber 48 provides a volume or warehouse for storing additional liquid after such liquid is passed through filter 46. Upper chamber 48 additionally provides a volume or warehouse for containing air within print cartridge 24 at a location removed or spaced from print head 42. In the embodiment illustrated, the volume provided by upper chamber 48 serves as an intermediate holding chamber or air purge chamber for containing air prior to its discharge through air discharge passage 52. Λs a result, air built up within print cartridge 24 during printing or throughout the life of print cartridge 24 is removed from print head 42, reducing or eliminating depriming, dry fire and otherwise premature failure.

[0027] According to one embodiment, upper chamber 48 has a volume of at least about 3 cc (3 milliliters) and the nominally about 5 cc (5 milliliters). In other embodiments, upper chamber 48 may have other dimensions. In some embodiments, upper chamber 48 may be omitted.

[0028] Liquid supply passage 50 comprises a liquid passage extending from an external port 76 to an outlet port 78 εit volume 70 of lower chamber 44. External port 76 is configured to mate or be fluidly connected to liquid source 34 so as to receive liquid from liquid source 34. In one embodiment, port 76 may include a septum for receiving a needle associated with liquid source 34. In another embodiment, port 76 may include a needle for being inserted into a septum associated with liquid source 34. In other embodiments, other fluid connection arrangements may be employed. [0029] Air discharge passage 52 comprises a pneumatic passage (a passage configured to guide and direct air or gaseous flow) pneumatically connected directly to each of volumes 70 and 72 of lower chamber 44. In other words, air discharge passage 52 is pneumatically connected to each of volumes 70 and 72 such that fluid may flow from volume 70 to air discharge passage 52 without having to pass through filter 46 and volume 72 and such that fluid may flow from volume 72 to air discharge passage 52 without having to pass through filter 46 and volume 70. This direct pneumatic connection facilitates removal of air from each of volume 70, 72 during filling and when filter 46 is wet, wherein we1 filter 46 may otherwise inhibit the flow of air across filter 46.

[0030] In the example illustrated, air discharge passage 52 is pneumatically connected to a first discharge port 80 of volume 70 and to a second air discharge port 82 of a volume 72. In the particular example illustrated, air discharge passage 52 is pneumatically connected to ports 80 and 82 via intermediate volumes or passages. For example, air discharge passage 52 is pneumatically connected to port 80 via air bypass passage 54 and upper chamber 48 through a port 88 in upper chamber 48. Air discharge passage 52 is pneumatically connected to port 82 via vent passage 56 and upper chamber 48. In other embodiments, air discharge passage 52 alternatively be pneumatically connected directly to ports 80 and 82 without intermediate volumes or passages. [0031] Air discharge passage 52 is further pneumatically connected to air discharge 36 through an air discharge port 86. Air discharge port 86 is configured to mate or be fluidly connected to air discharge 36. In one embodiment, port 86 may include a septum for receiving a needle associated with air discharge 36. In another embodiment, port 86 may include a needle for being inserted into a septum associated with air discharge 36. In other embodiments, other fluid connection arrangements may be employed. In yet another embodiment, port 86 may comprise a simple opening through which air is discharged to atmosphere.

[0032] Air bypass passage 54 comprises a liquid and pneumatic passage extending from volume 70 of lower chamber 44 to upper chamber 48. In particular, passage 54 extends from port 80 of volume 70 to port 88. Port 80 of volume 70 of lower chamber 44 is located vertically above port 78. As a result, as liquid or ink fills volume 70, air within volume 70 at a top of volume 70 is discharged through port 80 and through air bypass passage 54 to upper chamber 48 through port 88 and air discharge passage 52. Air bypass passage 54 inhibits or prevents liquid from bypassing filter 46 when valve 64 is closed.

[0033] Vent passage 56 comprises a liquid and pneumatic passage extending from port 82 of volume 72 to upper chamber 48 through a port 90 of upper chamber 48. Vent passage 56 permits liquid within volume 72 to continue to rise and flow into upper chamber 48 through passage 56. Because port 82 and vent passage 56 extend from an upper portion of volume 72, air within volume 72 naturally rises and is discharged from volume 72 through port 82 and passage 56 into upper chamber 48 where the air can be further discharged through port 85 and air discharge passage 52. As a result, a greater storage area or volume for collecting air on the print head side of filter 46 is provided. As noted above, this additional volume collects air built up within print cartridge 24 during printing or throughout the life of print cartridge 24 and removes air from print head 42, reducing or eliminating depriming, dry fire and otherwise premature failure. [00341 Sensor 58 comprises a liquid sensing device configured to sense a liquid or the presence of liquid. Sensor 58 is located and supported within upper chamber 48 at a maximum or near maximum level to which liquid is to fill upper chamber 48. Based upon signals from sensor 58, controller 38 generates control signals directing the actuation of valve systems 62, 64. In another embodiment, sensor 58 may be off board in passage 52 or in the fluid line between port 86 and air discharge 36. In the example illustrated, chamber 48 will not fill with liquid above the line level with outlet 85 regardless where the sensor 58 is located. Air above that level is trapped and cannot escape. Continued ink fill will cause ink to flow out passage 52 to port 86 where an ink air separator provided by air discharge would capture it. In such a embodiment, a sensor 58 in either passage 52 or between passage 52 and air discharge 36 would detect the presence of liquid, thereupon detection of the liquid, controller 38 may stop the fill process.

[0035] Valve system 62, 64 each comprise valving mechanisms configured to selectively, in response to control signals from controller 38, open and close port 78 and ports 85, 88, respectively. For example, in one embodiment, valve systems 62 and 64 open ports 78, 85 and 88 during filling of cartridge 24 with liquid from liquid source 34. This allows air being displaced by the liquid filling chambers 44 and 48 to be discharged through air discharge passage 52. When sufficiently filled, valve systems 62, 64 may be used to close ports 78, 85 and 88, wherein a back pressure may be created within volume 44, 48 to inhibit liquid drool through nozzles 68. In one embodiment, valve systems 62, 64 further assist in forming or regulating such back pressure. In particular embodiments, valve systems 62, 64 may be further utilized to selectively open and close ports 78, 85 and 88 to facilitate priming of nozzle 68.

[0036] Figures 4 and 5 schematically illustrate one example of valve system 62. In the example shown, valve system 62 includes paddles 92, 93, valve seat 94, bias 96, bag 98 and pressure source 100. Paddles 92, 93 comprise members movably supported by body 40. Paddle 92 supports valve seat 94. Paddle 92 is movably supported by body 40 for movement between a closing or sealing position (shown in Figure 4) in which valve seat 94 seals or closes off port 78 and an open position or state (shown in Figure 5) in which valve seat 94 is withdrawn from port 78. In the particular embodiments illustrated, paddles 92, 94 pivot about axes 102, 103 between the open position and the closed position. In other embodiments, paddles 92, 93 may move between such positions in other manners. In some embodiments in which other means are used to actuate or move paddle 92, paddle 93 may be omitted.

[0037] Valve seat 94 comprises a member configured to seal off or close an associated port or ports. A valve seat 94 is carried by paddle 92. In one embodiment, valve seat 94 comprises a compressible elastomeric member configured to be pivoted between the open position and the closed position. In other embodiments, valve seat 94 may have other configurations.

[0038] Bias 96 comprises one or more members configured to resiliently bias valve scat 94 to the closed position shown in Figure 4. In the example illustrates, bias 96 comprises a tension spring having opposite ends connected to paddles 92, 93 on an opposite side of axes 102, 103 as valve seat 94. In other embodiments, bias 96 may comprise other types of springs or other resilient biasing members.

[0039] Bag 98 comprises one or more structure defining an internal volume bound or surrounded by a flexible or stretchable outer wall, allowing bag 98 to expand and contract in response to pressure variations within its internal volume. Bag 98 is supported between paddles 92, 93 below axes 102, 103. The pressure within bag 98 may be controlled or varied by pressure source 100. The volume or space occupied by bag 98 within volume 70 also varies in response to the internal pressure applied to bag 98. Λs a result, the size of bag 98 maiy be varied or controlled to vary or regulate back pressure within volume 70 about the exterior of bag 98.

[0040] Pressure source 100 comprises a source of pressurized fluid, such as air or gas, in fluid communication with the interior of bag 98. In response to control signals received from controller 38 (shown in Figure 1), pressure source 100 inflates or deflates bag 98 to move or pivot paddles 92, 93 and to regulate the back pressure within volume 70. In the embodiment illustrated, as shown by Figure 4, deflation of bag 98 allows bias 96 to return paddles 92, 93 to their original default position, positioning valve seat 94 in the closed position. As shown by Figure 5, inflation of bag 98 by pressure source 100 causes bag 98 to expand against bias 96 to pivot paddles 92, 93 to withdraw valve scat 94 from port 78 to the open position. In other embodiments, actuation of valve seat 94 between the open position and the closed position may be achieved using bag 98 in other fashions or using other actuators for moving valve seat 94.

[0041] Valve system 64 is substantially identical to valve system 62 except that valve seat 94 of valve system 64 is configured to concurrently close or seal both ports 85 and 88 when in the closed position or state. Bias 96 of valve system 64 has a slightly larger spring force or spring constant as compared to bias 96 of valve system 62 such that upon deflation of bag 98, paddle 92 and valve seat 94 pivot from the withdrawn or open position to the closed position earlier in time as compared to paddle 92 and valve seat 94 of valve system 62 during deflation of bag 98. In other embodiments, bias 96 of valve system 64 may have a spring force or spring constant substantially equal to or even greater than that of bias 96 of valve system 62, wherein valve seat 94 of valve system 62 is moved in other fashions to the closed position at an earlier point in time during deflation of bag 98. For example, bag 98 of valve system 64 may also have a smaller volume or size as compared to bag 98 of valve system 62, wherein the smaller size of bag 98 causes valve seat 94 to move to the closed position at an earlier point in time during deflation of bag 98. In yet other embodiments, separate pressure systems 100 may be provided for each of bags 98 of systems 62, 64, wherein the inflation of bag 98 of system 64 is initiated at an earlier point in time as compared to deflation of bag 98 of system 62. In all other aspects, valve system 64 is substantially identical to valve system 62. In other embodiments, valve system 64 may be different than valve system 62. [0042] Figure 6 is a flow diagram illustrating one example method 120 for providing, filling, and using print cartridge 24. As indicated by step 122, cartridge 24, while empty or substantially empty, is vertically loaded or mounted in printer 22. In other words, print cartridge 24 is loaded such that print head 42 is in a substantially vertical orientation when mounted to dock 32. Upon being loaded onto dock 32 (also referred to as a printer pocket) in printer 22, print cartridge 22 is capped as shown in Figures 1 and 2. Because cartridge 24 is loaded into the printer while empty, cartridge 24 is devoid of liquid or ink which may be corrosive or damaging to print head 42 or other components of print cartridge 24 during shipment, when being inventoried or during retail display. As a result, cartridge 24 may have a prolonged life and may achieve enhanced print quality during its life.

[0043] Once print cartridge 24 has been loaded or mounted to dock 32, print cartridge 24 may be filled with liquid. Steps 124-132 outline a remainder of the method in which the cartridge 24 is filled. As indicated by step 124, valve system 62 and 64 are actuated or moved to open positions in which ports 78, 85 and 88 are each opened. In the example illustrated in which valve systems 62 and 64 are configured as shown in Figures 4 and 5, controller 38 generates control signals directing pressure source 100 to apply blow prime pressure to bag 98 of each of valve system 62 and 64 so as to inflate bags 98. Upon being sufficiently inflated, bags 98 pivot paddles 92, 93 against bias 96 to pivot or withdraw of seat 94 out of the sealing contact with ports 78, 85 and 88, opening ports 78, 85 and 88.

[0044] As indicated by step 126, lower chamber 44 is initially filled with liquid. The filling of chamber 44 is shown in Figure 1. To fill chamber 44, controller 38 generates control signals directing liquid source 34 to supply pressurized liquid or ink to ink supply passage 50. In one embodiment, the pressurized liquid is delivered to a needle which directs the pressurized liquid into ink supply passage 50. The pressurized liquid flows through ink passage 50 into lower chamber 44 as indicated by arrows 140, pushing existing air ahead of it. As the liquid 127 fills lower chamber 44, air above liquid 127 is vented from chamber 44. In particular, air within volume 70 flows through passage 54 into upper chamber 48 as indicated by arrows 142. Air within volume 72 is vented through passage 56 into upper chamber 48 as indicated by arrows 145. Even though filter 46 may become wet and may inhibit the passage of air across filter 46, air on both sides of filter 46 is vented towards their discharge passage 52. Air within upper chamber 48 is further discharged through air discharge passage 52 to air discharge 36 as indicated by arrows 147.

[0045] As indicated by step 128 and shown in Figure 2, once liquid being supplied through the supply passage 50 has completely or substantially filled lower chamber 44, the liquid passes through passage 56 and begins to fill upper chamber 48. Upper chamber 48 provides additional liquid storage capacity for cartridge 24. As upper chamber 48 is filled with liquid, air continues to be pushed through air discharge passage 52 to air discharge 36 as indicated by arrows 146.

[0046] As indicated by steps 130 and 132 in Figure 6 and shown by Figure 3, valve systems 62 and 64 move to closed positions closing ports 78, 85 and 88. In the example illustrated, sensor 58 detects liquid or ink at a preselected fill level or height within upper chamber 48. Although sensor 58 is illustrated in located within upper chamber 48 such that the desire to level is located within upper chamber 48, in other embodiments, sensor 50 may be located at other locations depending upon a desired fill level or location. For example, in other embodiments, sensor 50 may be located within their discharge passage 146. In one embodiment, sensor 58 may be located proximate to ports 76 so as to provide a fill signal when liquid or ink is proximate to discharge ports 76 or proximate to a needle from air discharge 36.

[0047] In response to signals from sensor 58, controller 38 generates control signals stopping the supply of additional liquid by liquid source 34. Controller 38 further generates control signals aduating valve systems 62 and 64 to the closed positions. In the example illustrated in which valve system 62 and 64 are as shown in Figures 4 and 5, controller 38 generates control signals directing pressure source 100 (associated with each of valve system 62, 64) to depressurize and deflate each of bags 98 of system 62, 64. In one embodiment, this may be simply venting air within each of bags 98 to atmosphere. As shown by Figure 4, such deflation allows bias 96 to move valve seat 94 of each of systems 62, 64 to a closed slate or position. As a result, liquid within chambers 44 and 48 displaces the reduced volume occupied by each of the bags 98. This establishes a back pressure to minimize or inhibit liquid or ink drool. As shown in Figure 3, print cartridge 24 may be moved to a printing position opposite to media transport 30, wherein a print medium 26 may be positioned opposite to print head 42 for printing. [0048] To prime nozzle 68 of print head 42, controller 38 generates control signals actuating valve system 62 to the opened state or position and further directing liquid source 34 to supply additional liquid to cartridge 24. Concurrently with the actuation of valve system 62 to an open position, controller 30 may also generate control signals actuating valve systems 64 to the open state to vent additional air from cartridge 24. [0049] Print cartridge 24 further facilitates removal of liquid from print cartridge 24 at the end of its life. To drain liquid or ink from print cartridge 24 at the end of his life, controller 38 generates control signals directing pressure source 100 of systems 62 and 64 to inflate bags 98 or to otherwise open ports 78, 85 and 88. Controller 38 further generates control signals directing air discharge 36 to alternatively supply pressurized air through port 86. If cartridge 24 is capped and liquid supply 36 is depressuri/ed, liquid or ink is pushed back into liquid supply 34, removing most of the remaining liquid or ink

- U- from cartridge 24 at the end of its life. In other embodiments, one or more of such steps may be omitted or may be rearranged in order. fOOSO] Although print cartridge 24 is well suited for vertical loading into a printer, in other embodiments, print cartridge 24 may be horizontally loaded into a printer. If filled in the horizontal position, both volumes/chambers 44,48 fill at the same time but the end result is the same. Air is purged out the top, transferred to the third volume and purged out passage 52.

[0051] Figures 7-9 illustrate print cartridge 224, a particular example of print cartridge 24. Figure 7 illustrates print cartridge 224 mounted in printer 22. Figures 8 and 9 illustrate a top portion of print cartridge 224. Print cartridge 224 is configured to be utilized in a printer including printer 22 or other similar printers. Like print cartridge 24, print cartridge 224 is configured to be filled with liquid or ink while mounted within printer 22 in a vertical orientation. During such filling, air is discharged or vented. In the particular embodiment illustrated, print cartridge 224 additionally provides an enlarged internal wall human for storing air during use of the print cartridge 124. As a result, print cartridge 224 may be shipped from the factory while empty, may be filled by an end-user and may provide enhanced printing performance.

[0052] Print cartridge 224 comprises body 240, print head 242, lower chamber 244, filter 246, upper chamber 248, liquid supply passage 250, air discharge passage 252, air bypass passage 254, vent passage 256, sensor 258 and valve systems 262, 264. Body 240 comprises one or more structures which cooperate to form or enclose the remaining components of cartridge 224. In particular, body 240 forms lower chamber 244, upper chamber 248, liquid supply passage 250, air discharge passage 252, air bypass passage 254, vent passage 256. Body 240 supports and encloses print head 242, filter 246, sensor 258 and valve systems 262, 264.

[0053] In the particular example illustrated, body 240 includes a lower portion 330 and a crown 332. Lower portion 330 forms lower chamber 244, upper chamber 246 and vent passage 256. Lower portion 330 has an open top or side (facing to the right in Figure 7). [0054] Crown 332 covers or caps the open side of lower portion 330. Crown 332 further provides liquid supply passage 250, air discharge passage 252 and air bypass passage 254. According to one embodiment, crown 332 is formed from an upper half and a lower half 338 (shown in Figures 7 and 8), wherein the two halves substantially mirror one another to form opposite sides of liquid supply passage 250, air discharge passage 252 and air bypass passage 254. Although not shown, the upper half of crown 332 has a lower face mirroring the upper face of the bottom half of crown 332. Figure 8 illustrates a top side or top face of a lower crown half 338 while Figure 9 illustrates a bottom side or bottom face of the lower crown half 338. The top side or top face of crown half 338 faces away from chambers 244 and 148. In other embodiments, crown 332 may be formed from greater or fewer parts.

[0055] Print head 242 comprises one or more print heads having nozzles through which liquid is selectively ejected or discharged. In one embodiment, print head 242 may comprise one or more thermoresistive inkjet print heads. In another embodiment, print head 242 may comprise one or more piezo resistive inkjet print heads. In other embodiments, print head 242 may comprise other types of print heads configured to selectively eject liquid.

[0056] As shown by Figure 7, print head 242 is mounted to and supported by body 240 so as to extend in a substantially vertical orientation when print cartridge 224 is mounted to dock 32 and when print cartridge 224 is ejecting liquid onto print medium 26 positioned by printer 22. In the particular example illustrated, print head 242 is supported by body 240 so as to extend in a vertical plane (90° from horizontal) when print cartridge 224 is mounted to dock 32. In other embodiments, print head 242 may be supported by body 240 in other vertical orientations.

[0057] Lower chamber 244 extends opposite to print head 242. Lower chamber 244 is located at a lower end of print cartridge 224, below upper chamber 248, when print cartridge 224 is mounted or docked to dock 32. Lower chamber 244 includes volumes 270 and 272 which are separated from one another by filter 246. Volume 270 receives liquid from liquid source 34 through liquid supply passage 250. Volume 272 extends adjacent to print head 242 and receives liquid from volume 270 after the liquid has passed through filter 246. Filter 246 filters such liquid prior to the liquid being presented to print head 242.

[0058] Upper chamber 248 is located at an upper end of print cartridge 224, above lower chamber 244. Upper chamber 248 provides a volume for storing additional liquid after such liquid is passed through filter 246. Upper chamber 248 additionally provides a volume or warehouse for containing air within print cartridge 24 at a location removed or spaced from print head 242. In the embodiment illustrated, the volume provided by upper chamber 248 serves as an intermediate holding or air purge chamber for containing air prior to its discharge through air discharge passage 252. As a result, air built up within print cartridge 224 during printing or throughout the life of print cartridge 224 is removed from print head 422, reducing or eliminating depriming, dry fire and otherwise premature failure.

[0059] According to one embodiment, upper chamber 48 has a volume of at least about 3 cc (3 milliliters) and nominally about 5 cc (5 milliliters). In other embodiments, upper chamber 248 may have other dimensions. In some embodiments, upper chamber 248 may be omitted.

[0060] As most clearly shown in Figure 8, liquid supply passage 250 comprises a liquid passage extending from an external port 276 to an outlet port 278 at volume 270 of lower chamber 244. External port 276 is configured to mate or be fluidly connected to liquid source 234 so as to receive liquid from liquid source 234. In one embodiment, port 276 may include a septum (not shown) for receiving a needle associated with liquid source 34. In another embodiment, port 276 may include a needle for being inserted into a septum associated with liquid source 34. In other embodiments, other fluid connection arrangements may be employed.

[0061] As most clearly shown in Figure 8, air discharge passage 252 comprises a pneumatic passage (a passage configured to guide and direct air or gaseous flow) pneumatically connected directly to each of volumes 270 and 722 of lower chamber 244. In other words, air discharge passage 252 is pneumatically connected to each of volumes

46- 270 and 272 such that fluid may flow from volume 270 to air discharge passage 252 without having to pass through filter 246 and volume 272 and such that fluid may flow from volume 272 to air discharge passage 252 without having to pass through filter 246 and volume 270. This direct pneumatic connection facilitates removal of air from each of volumes 270, 272 during filling and when filter 246 is wet, wherein wet filter 246 may otherwise inhibit the flow of air across filter 246.

[0062] In the example illustrated, air discharge passage 252 is pneumatically connected to a first discharge port 280 of volume 270 and a second air discharge port 282 of a volume 272. In the particular example illustrated, air discharge passage 252 is pneumatically connected to ports 280 and 282 via intermediate volumes or passages. For example, air discharge passage 252 is pneumatically connected to port 280 via air bypass passage 254 and upper chamber 248 through a port 288 in upper chamber 248. Λir discharge passage 252 is pneumatically connected to port 282 via vent passage 256 and upper chamber 248. In other embodiments, air discharge passage 52 may alternatively be pneumatically connected directory to ports 280 and 282 without intermediate volumes or passages.

[0063] Air discharge passage 252 is further pneumatically connected to air discharge 36 (shown in Figure 1) through an air discharge port 286. Air discharge port 286 is configured to mate or be fluidly connected to air discharge 36. In one embodiment, port 286 may include a septum for receiving a needle associated with air discharge 36. In another embodiment, port 286 may include a needle for being inserted into a septum associated with air discharge 36. In other embodiments, other fluid connection arrangements may be employed. In yet another embodiment, port 286 may comprise a simple opening through which air is discharged to atmosphere. [0064] Air bypass passage 254 comprises a liquid and pneumatic passage extending from volume 270 of lower chamber 244 to upper chamber 248. In particular, passage 254 extends from port 280 of volume 270 to port 288. Port 280 of volume 270 of lower chamber 244 is located vertically above port 278. As a result, as liquid or ink fills volume 270, air within volume 270 at a top of volume 720 is discharged through port 280 and through air bypass passage 254 to upper chamber 248 through port 288 and air discharge passage 252.

[0065] Vent passage 256 comprises a liquid and pneumatic passage extending from port 282 of volume 272 to upper chamber 248 through a port 290 of upper chamber 248. Vent passage 256 permits liquid within volume 272 to continue to rise and flow into upper chamber 248 through passage 256. Because port 282 and vent passage 256 extend from an upper portion of volume 272, air within volume 272 naturally rises and is discharged from volume 272 through port 282 and passage 256 into upper chamber 248 where the air can be further discharged through port 285 and air discharge passage 252. As a result, a greater storage area or volume for collecting air on the print head side (the side of filter 246 closest to print head 242) of filter 246 is provided. As noted above, this additional volume collects air built up within print cartridge 224 during printing or throughout the life of print cartridge 224 and removes air from print head 242, reducing or eliminating depriming, dry fire and otherwise premature failure. [0066] Sensor 258 comprises a liquid sensing device configured to sense a liquid or the presence of liquid. Sensor 258 is located and supported within upper chamber 248 at a maximum or near maximum level to which liquid is to fill upper chamber 48. Based upon signals from sensor 258, controller 38 generates control signals directing the actuation of valve system 262, 264.

[0067] Valve system 262, 264 each comprise valving mechanisms configured to selectively, in response to control signals from controller 38, open and close port 278 and ports 285, 288, respectively. For example, in one embodiment, valve systems 262 and 264 open ports 278, 285 and 288 during filling a cartridge 224 with liquid from liquid source 34. This allows air being displaced by the liquid filling chambers 244 and 248 to be discharged through air discharge passage 252. When sufficiently filled, valve systems 262, 264 may be used to close ports 278, 285 and 288, wherein a back pressure may be created within volume 244, 248 to inhibit liquid drool through nozzles of print head 242. In the example illustrated, valve systems 262, 264 further assist in forming or regulating such back pressure. In particular embodiments, valve systems 262, 264 may be further utilized to selectively open and close ports 278, 285 and 288 to facilitate priming of the nozzles.

[0068] Valve systems 262, 264 are substantially similar to valve system 62 shown in Figures 4 and 5. As shown by Figure 7, valve systems 262, 264 each include paddles 292, 93 (schematically shown in Figure 4), valve seat 294, bias 296, bag 298 (schematically shown) and pressure source 100 (provided as part of printer 22). Paddles 292, 93 comprise members movably supported by body 240. Paddle 292 of each system 262, 264 supports valve seat 294. Paddle 292 of valve system 262 is movably supported by body 240 for movement between a closing or sealing position (shown in Figure 7) in which valve seat 294 seals or closes off port 78 and an open position or state in which valve seat 94 is withdrawn from port 78 (similar to the position of valve seat 94 shown in Figure 5). Paddle 292 of valve system 264 is movably supported by body 240 for movement between a closing or sealing position (shown in Figure 7) in which valve seat 294 seals or closes off ports 285, 288 and an open position or state in which valve seat 94 is withdrawn from port 285, 288 (similar to the position of valve seat 94 shown in Figure 5). In the particular embodiments illustrated, paddles 292, 93 pivot about axis 202 between the open position and the closed position. In other embodiments, paddles 292, 93 may move between such positions in other manners. In some embodiments in which other means are used to actuate or move paddle 292, paddle 93 may be omitted. [0069] Valve seat 294 comprises a member configured to seal off or close an associated port or ports. A valve seat 294 is carried by paddle 92. In one embodiment, valve seat 294 comprises a compressible elastomeric member configured to be pivoted between the open position and the closed position. In other embodiments, valve seat 294 may have other configurations.

[0070] Bias 296 of each system 262, 264 comprises one or more members configured to resiliently bias valve seat 294 to the closed position shown in Figure 7. In the example illustrates, bias 296 comprises a tension spring having opposite ends connected to paddles 292, 93 on an opposite side of axes 202as valve seat 294. In other embodiments, bias 296 may comprise other types of springs or other resilient biasing members at other locations. For example, bias 296 may alternatively comprise a compression spring on the same side of axis 20 to as valve seat 294.

[0071] Bag 298 of each of systems 262, 264 comprises one or more structure defining an internal volume pounded by a flexible or stretchable outer wall, allowing bag 298 to expand and contract in response to pressure variations within its internal volume. Bag 298 is supported between paddles 292, 93 below axis 202. The pressure within bag 298 may be controlled or varied by pressure source 100. The volume or space occupied by bag 298 within volume 270 and within upper chamber 248 also varies in response to the internal pressure applied to bag 298. As a result, the size of bags 298 may be varied or controlled to vary or regulate back pressure within volume 270 and within upper chamber 248 about the exterior of bags 298.

[0072] Pressure source 100 is described above with respect to Figures 4 and 5. Λs noted above, pressure source 100 comprises a source of pressurized fluid, such as air or gas, in fluid communication with the interior of bag 98. In response to control signals received from controller 38 (shown in Figure seven), pressure source 100 inflates or deflates bags 298 to move or pivot paddles 292, 93 and to regulate the back pressure within volume 70 and within upper chamber 248. Deflation of bag 298 allows bias 296 to return paddles 292, 93 to their original default position, positioning valve seat 294 in the closed position. Inflation of bag 298 of each of systems 262, 264 by pressure sources 100 causes bags 298 to expand against bias 296 to pivot paddles 292, 93 to withdraw valve seat 294 of system 262 from port 278 to the open position and to withdraw valve seat 294 of system 264 from ports 285, 288 to the open position. In other embodiments, actuation of valve seat 294 of each of systems 262, 264 between the open position and the closed position may be achieved using bag 298 in other fashions or using other actuators for moving valve seat 294. Although Figure 7 illustrates a single pressure source 100, in other embodiments, multiple separate pressure sources may be used for each of systems 262, 264.

[0073] As noted above, valve system 264 is substantially identical to valve system 262. However, in the example illustrated, valve seat 294 of valve system 264 is configured to concurrently close or seal both ports 285 and 288 when in the closed position or state. Bias 296 of valve system 64 has a slightly larger spring force or spring constant as compared to bias 926 of valve system 262 such that upon deflation of bag 298, paddle 292 and valve seat 294 pivot from the withdrawn or open position to the closed position earlier in time as compared to paddle 292 and valve seat 294 of valve system 262. In other embodiments, the earlier closing of ports 285, 288 may be achieved in other fashions. For example, in other embodiments, system 264 may include a bag 298 that is smaller than the bag 298 of system 262.

[0074] Although the present disclosure has been described with reference to example embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the claimed subject matter. For example, although different example embodiments may have been described as including one or more features providing one or more benefits, it is contemplated that the described features may be interchanged with one another or alternatively be combined with one another in the described example embodiments or in other alternative embodiments. Because the technology of the present disclosure is relatively complex, not all changes in the technology are foreseeable. The present disclosure described with reference to the example embodiments and set forth in the following claims is manifestly intended to be as broad as possible. For example, unless specifically otherwise noted, the claims reciting a single particular element also encompass a plurality of such particular elements.

Claims

WHAT IS CLAIMED IS:

L A print cartridge (24, 224) comprising: a print head (42, 242); a first volume (72, 272) adjacent to the print head (42, 242); a second volume (70, 270); a filter (46, 246) between the first volume (72, 272) and the second volume (70, 270) to filter liquid flow from the second volume (70, 270) to the first volume (72, 272); a liquid supply passage (50, 250) connected to the second volume (70, 270); and an air discharge passage connected to the first volume (72, 272) through a first port (82, 282) on a first side of the filter (46, 246) and connected to the second volume (70, 270) through a second port (80, 280) on a second side of the filter (46, 246).

2. The print cartridge of claim 1 further comprising: a first valve (62, 262) configured to selectively open and close the liquid supply passage (50, 250); and a second valve (64, 264) configured to selectively open and close the air discharge passage (85, 285).

3. The print cartridge of claim 2 further comprising a first selectively inflatable and deflatable bag (98, 298) in the second volume (70, 270) configured to actuate the first valve (62, 262).

4. The print cartridge of claim 3 further comprising: a third volume (48, 248) between the air discharge passage (52, 252) and the first volume (72, 272), the third volume (48, 248) connected to the first port (82, 282); and a second selectively inflatable and deflatable bag (98, 298) in the third volume (48, 248) configured to actuate the second valve (64, 264).

5. The print cartridge of claim 1 further comprising: a third volume (48, 248) between the air discharge passage (52, 252) and the first volume (72, 272), the third volume (48, 248) connected to the first port (82, 282); and an air bypass passage (54, 254) extending from the second port (80, 280) to the third volume (48, 248).

6. The print cartridge of claim 5 further comprising a vent passage (56, 256) extending from the first port (82, 282) to the third volume (48, 248).

7. The print cartridge of claim 5, wherein the third volume (48, 248) has a volume of at least about 5 cc.

8. The print cartridge of claim 5 further comprising: a first valve (62, 262) configured to selectively open and close the liquid supply passage (50, 250); a second valve (64, 264) configured to selectively open and close the air discharge passage (52, 252); a first selectively inflatable and deflatable bag (98, 298) in the second volume (70, 270) configured to actuate the first valve (62, 262); and a second selectively inflatable and deflatable bag (98, 298) in the third volume (48, 248) configured to actuate the second valve (64, 264).

9. The print cartridge of claim 8, wherein deflation of the first bag (98, 298) actuates the first valve is configured to open the liquid supply passage (50, 250) and wherein deflation of the second bag (98, 298) actuates the second valve (64, 264) to open the air discharge passage (52, 252).

10. The print cartridge of claim 9, wherein the second valve (64, 264) is configured to open the liquid supply passage (50, 250) before the first valve (62, 262) opens the air discharge passage (52, 252).

11. The print cartridge of claim 8, wherein the second valve (64, 264) closes the air bypass passage (54, 254) concurrently with closing of the air discharge passage (52, 252).

12. The print cartridge of claim 8, further comprising paddles (292, 93) on opposite sides of the second inflatable bag (98, 298), wherein the second valve (64, 264) includes a valve seat (294) carried by one of the paddles (292, 93).

13. The print cartridge of claim 1 , wherein the print cartridge is configured to be supported by a printer (22) in an orientation such that the print head (42, 242) extends in a vertical plane.

14. The print cartridge of claim 13, wherein the print cartridge (24, 224) is configured to also operate when supported by the printer in a second orientation in which the print head (42, 242) extends in a substantially horizontal plane.

15. The print cartridge of claim 1, wherein the third volume (48, 248) overlies the first volume during printing.