BACKGROUND
A challenge exists to deliver quality and value to consumers, for example, by providing reliable printing devices that are cost effective. Further, businesses may desire to enhance the performance of their printing devices, for example, by increasing the speed and accuracy of the functioning of one or more components of such printing devices.
BRIEF DESCRIPTION OF THE DRAWINGS
The following detailed description references the drawings, wherein:
FIG. 1 is a view of an example of a printing device.
FIG. 2 is view of an example of a printing assembly.
FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2.
FIG. 4 is an example of an enlarged view of a member or printhead.
FIG. 5 is an enlarged view of the circled area of FIG. 3.
FIGS. 6
a-6e illustrate an example of a bubble purging assembly.
FIG. 7 is an enlarged view of an alternative example of a portion of a fluid dispenser.
FIG. 8 is an enlarged view of another example of a portion of a fluid dispenser.
FIG. 9 is an enlarged view of a further example of a portion of a fluid dispenser.
FIG. 10 is an enlarged view of yet a further example of a portion of a fluid dispenser.
DETAILED DESCRIPTION
Reliability of fluid dispensers, such as inkjet printheads used in printing devices, is desirable. Quality of fluid dispenser output (e.g., print resolution) is also desirable. Throughput, such as printed output pages per minute, is also a design consideration.
An example of a printing device 10 is shown in FIG. 1. Printing device 10 includes a housing 12 in which components of the printing device 10 are enclosed, a print media input tray 14 that stores a supply of print media (not shown), and an access door 16 that may be opened in the direction of arrow 18 to provide access to interior 20. Printing device 10 additionally includes a printing assembly 22 located in interior 20 that places text and images on print media as it is transported from input tray 14 to print media output tray 24 where it may be collected by end users. As can be seen in FIG. 1, printing assembly 22 is mounted in interior 20 of printing device 10 by a support assembly 26. Printing device 10 additionally includes a user interface 28 for controlling printing device 10 and providing status information to end users. It is to be understood that some components of printing device 10 are not shown in FIG. 1, such as a print media transport mechanism, control electronics, servicing components for printing assembly 22, a duplex mechanism, etc.
An example of a printing assembly 22 is shown in FIG. 2. As can be seen in FIG. 2, printing assembly 22 includes a fluid dispenser 30 and a plurality of fluid containers 32, 34, and 36. Fluid containers 32, 34, and 36 are each configured to store a fluid that is supplied to fluid dispenser 30 via connection assembly 38 shown in FIG. 2. In this example, the fluid is ink of different colors, but may be different in other examples and applications (e.g., fixer, paint, biological material, etc.). Although only three containers are shown in FIG. 2, it is to be understood that four are actually utilized in the illustrated example. It is also to be understood that other examples may utilize a greater or lesser number of fluid containers.
Fluid dispenser 30 includes a plurality of members 40, 42, 44, 46, 48, 50, 52, 54, 56, and 58 each of which includes a plurality of orifices (not shown in FIG. 2) through which the fluid stored in containers 32, 34, and 36 is ultimately ejected. In the example shown, each member 40, 42, 44, 46, 48, 50, 52, 54, 56, and 58 is a printhead, as discussed more fully below. Fluid dispenser 30 additionally includes a fluid delivery assembly 60 that is coupled to fluid containers 32, 34, and 36 and members 40, 42, 44, 46, 48, 50, 52, 54, 56, and 58 to conduct the fluid from containers 32, 34, and 36 to the orifices of members 40, 42, 44, 46, 48, 50, 52, 54, 56, and 58. Fluid delivery assembly 60 is configured to include a bubble purging assembly that conducts any bubbles that result from ejection of the fluid from the orifices, as well as any bubbles arising from increasing a temperature of the fluid, to fluid containers 32, 34, and 36 to help prevent clogging of fluid delivery assembly 60. This, in turn, helps maintain the reliability of printing device 10, as well as its output print quality and throughput.
A cross-sectional view taken along line 3-3 of FIG. 2 is shown in FIG. 3. As can be seen in FIG. 3, fluid delivery assembly 60 includes a manifold 62 that includes plurality of differently slanted fluid passageways 64, 66, 68, and 70 each of which is configured to have a different angle relative to member 44 as shown. Fluid delivery assembly 60 additionally includes a plurality of slots 72, 74, 76, and 78 each of which is coupled to a different respective fluid passageway 64, 66, 68, and 70 of manifold 62 to conduct fluid from fluid passageways 64, 66, 68, and 70 towards the orifices (not shown in FIG. 3) of member 44. In the example shown in FIG. 3, the orientation of the fluid assembly 60 is manifold 62 above member 44, which in turn is above the orifices (not shown). This orientation enables buoyant conveyance of bubbles from the orifices through the member 44 and through the manifold 62. In the example shown in FIG. 3, fluid passageway 64 conducts yellow ink, fluid passageway 66 conducts magenta ink, fluid passageway 68 conducts cyan ink, and fluid passageway 70 conducts black ink.
Slanted fluid passageways 64, 66, 68, and 70 are angled to enable close placement of adjacent staggered members 40, 42, 44, 46, 48, 50, 52, 54, 56, and 58 on print bar 80 (see FIG. 2) of fluid dispenser 30. This grouping of printheads 40, 42, 44, 46, 48, 50, 52, 54, 56, and 58 allows printing device 10 to print across the full width of print media simultaneously which increases the throughput of printing device 10. Manifold 62 of fluid delivery assembly 60 is configured to include additional slots and slanted fluid passageways (neither of which are shown) for each of members 40, 42, 46, 48, 50, 52, 54, 56, and 58 to conduct fluid from containers 32, 34, and 36. The angles and shapes of these additional fluid passageways and slots may be the same or different than those shown for fluid passageways 64, 66, 68, and 70 and slots 72, 74, 76, and 78.
Referring again to FIG. 3, each of fluid passageways 64, 66, 68, and 70 is defined by a different pair of walls or members 82, 84, 86, 88, and 90 of manifold 62, as shown. As can also be seen in FIG. 3, each of slots 72, 74, 76, and 78 is defined by a different pair of walls or members 92, 94, 96, 98, and 100 of printhead 44. As can further be seen in FIG. 3, each of fluid passageways 64, 66, 68, and 70 is configured to have a different cross-sectional width adjacent the respective slot 72, 74, 76, and 78 to which the fluid passageway is coupled.
An enlarged view of member or printhead 44 is shown in FIG. 4. Slots 72, 74, 76, and 78 can be seen, as can respective orifices 102, 104, 106, and 108, referenced above. Printhead 44 additionally includes a plurality of fluid chambers 110, 112, 114, and 116, each of which are coupled to respective slots 72, 74, 76, and 78, and each of which are configured to receive a supply of fluid from a different one of slots 72, 74, 76, 78. In the example shown in FIG. 4, fluid chambers 110 receive yellow ink via slot 72, fluid chambers 112 receive magenta ink from slot 74, fluid chambers 114 receive cyan ink from slot 76, and fluid chambers 116 receive black ink from slot 78.
As can be seen in FIG. 4, printhead 44 additionally includes a plurality of actuators 118, 120, 122, and 124 positioned in respective fluid chambers 110, 112, 114, and 116. Actuators 118, 120, 122, and 124 are configured on actuation to eject a drop of fluid through one of the respective orifices 102, 104, 106, and 108. In the example shown in FIG. 4, actuators 118, 120, 122, and 124 are resistors that are energized to heat the fluid in respective chambers 110, 112, 114, and 116 to a boiling point that forms drops that are ejected through respective orifices 102, 104, 106, and 108.
An enlarged view of the circled area of FIG. 3 is shown in FIG. 5. As can be seen in FIG. 5, members 84 and 86 of manifold 62 (which define fluid passageway 66) are attached to respective walls 94 and 96 of substrate 126 (which define slot 74) by an adhesive 128. In this example, manifold 62 is made from an inert material, such as a plastic or other polymer, metal, or ceramic, each of which tends not to interact with the fluid. Substrate 126 is formed from a suitable semiconductor material such as silicon. As can also be seen in FIG. 5, actuators 120 are positioned on a thinfilm layer 130 that is deposited on substrate 126. In this example, thinfilm layer 130 is made from a suitable material that insulates the conductors going to actuators 120 (not shown) that are positioned therein. Actuators 120 are made from any suitable resistive material, such as tungsten silicon nitride, which heats upon application of power thereto. Member 44 forms both the firing chamber and the orifice plate. Suitable materials for member 44 include a photoimageable epoxy such as SU8 or dielectric materials such as silicon oxide, silicon carbide, or silicon nitride.
An example of a bubble purging assembly of the present invention is illustrated in FIGS. 6a-6e. More specifically, FIG. 6a shows a drop 134 of fluid (not shown) that has been ejected through orifice 104 via energizing actuator 120 to heat the fluid to a sufficient level. This fluid is supplied by one of containers 32, 34, or 36 via fluid passageway 66 and slot 74 to chamber 112. Energizing actuator 120, which leads to ejected drop 134, additionally heats thinfilm layer 130 and silicon 126 which heats the fluid and leads to formation of bubble 136 because the heated fluid has a lower solubility for dissolved air. Additionally bubble 136 may form in fluid chamber 112 either from ejecting drop 134 or ingesting an air bubble during refill of chamber 112. Bubble 136 by itself or in combination with other bubbles (not shown) may clog or block fluid delivery assembly 60 which is undesirable. To help prevent this from occurring, bubbles, such as bubble 136, need to be buoyantly conveyed away from fluid chamber 112 through slot 74 and passageway 66 to a safe air storage location (not shown). The geometric shape of slot 74 and the relative cross-sectional widths of slot 74, adhesive 128, and fluid passageway 66 help achieve this desired result.
As can be seen in FIG. 6b, bubble 136 has traveled from its original position in chamber 112 shown in FIG. 6a to the position in slot 74 that is shown. As can also be seen in FIG. 6b, slot 74 is configured to increase in taper in a direction away from member 44 toward adhesive 128. That is, the cross-sectional width of slot 74 adjacent member 44 is less than the cross-sectional width adjacent adhesive 128. This helps encourage bubble 136 to travel through the fluid in the direction of arrow 138 to the position shown in FIG. 6c.
As can be seen in FIG. 6d, the cross sectional width of adhesive 128 is configured to be greater than the cross-sectional width of adjacent slot 74. This helps facilitate the conveyance of bubble 136 from slot 74 through the fluid toward fluid passageway 66, as generally indicated by arrow 138. As can also be seen, the cross-sectional width of fluid passageway 66 adjacent adhesive 128 is configured to be greater than adhesive 128. This helps facilitate the conveyance of bubble 136 from adhesive 128 into fluid passageway 66, as shown in FIG. 6e. In some examples, a height of adhesive 128 is configured to be approximately less than one-half (½) the cross-sectional width of the opening of adhesive 128. As can be seen in FIG. 6e, fluid passageway 66 is configured to increase in taper in a direction away from member 44 and adhesive 128 toward fluid containers 32, 34, and 36. That is, the cross-sectional width of fluid passageway 66 increases in a direction away from adhesive 128. This helps encourage bubble 136 to travel through the fluid in the direction of arrow 138 to the position shown in FIG. 6e and ultimately to a safe air storage location (not shown).
An enlarged view of an alternative example of a portion of a fluid dispenser 140 is shown in FIG. 7. As can be seen in FIG. 7, fluid delivery assembly 142 of fluid dispenser 140 includes a manifold 144 that is configured to include a plurality of differently slanted fluid passageways 146, 148, 150, and 152 each of which is configured to have a different angle relative to member 154 as shown. Fluid delivery assembly 142 additionally includes a plurality of slots 156, 158, 160, and 162 each of which is coupled to a different respective fluid passageway 146, 148, 150, and 152 of manifold 144 to conduct fluid from fluid passageways 146, 148, 150, and 152 towards orifices 164 of member 154. In this example, slots 156, 158, 160, and 162 are configured to have a substantially similar shape. Additionally, each of fluid passageways 146, 148, 150, and 152 are configured to have a substantially similar cross-sectional width adjacent respective slots 156, 158, 160, and 162, as generally indicated by double arrows 166.
An enlarged view of another example of a portion of a fluid dispenser 168 is shown in FIG. 8. As can be seen in FIG. 8, fluid delivery assembly 170 of fluid dispenser 168 includes a manifold 172 that is configured to include a plurality of differently slanted fluid passageways 174, 176, 178, and 180 each of which is configured to have a different angle relative to member 182 as shown. Fluid delivery assembly 170 additionally includes a plurality of slots 184, 186, 188, and 190 each of which is coupled to a different respective fluid passageway 174, 176, 178, and 180 of manifold 172 to conduct fluid from fluid passageways 174, 176, 178, and 180 towards orifices 192 of member 182. In this example, fluid passageway 174 is configured to have a greater cross-sectional width adjacent slot 184 than fluid passageways 176, 178, and 180 adjacent respective slots 186, 188, and 190, as generally indicated by double arrows 194 and 196. The greater cross-section width 194 enables a bubble the size of the backside of slot 184 to convey through fluid passageway 174. Thus, a bubble of a size, as generally indicated by double arrow 200, is smaller in size than any minimum fluidic width of fluid passageway 174.
An enlarged view of a further example of a portion of a fluid dispenser 202 is shown in FIG. 9. As can be seen in FIG. 9, fluid delivery assembly 204 of fluid dispenser 202 includes a manifold 206 that is configured to include a plurality of differently slanted fluid passageways 208, 210, 212, and 214 each of which is configured to have a different angle relative to member 216 as shown. Fluid delivery assembly 204 additionally includes a plurality of slots 218, 220, 222, and 224 each of which is coupled to a different respective fluid passageway 208, 210, 212, and 214 of manifold 206 to conduct fluid from fluid passageways 208, 210, 212, and 214 towards orifices 226 of member 216. In this example, each of slots 218, 220, 222, and 224 are configured to have a different geometric shape. Also in this example, as can be seen, slot 218 is asymmetrically configured. Additionally, each of fluid passageways 208, 210, 212, and 214 are configured to have a substantially similar cross-sectional width adjacent respective slots 218, 220, 222, and 224, as generally indicated by double arrows 228. Each of the slots 218, 220, 222 and 224 are configured such that the maximum backside dimension is smaller than the minimum fluidic width of fluid passageways 208, 210, 212 and 214 respectively. This is to limit bubble size at the exit of slots 218, 220, 222 and 224 to convey bubbles through passageways 208, 210, 212 and 214 respectively.
An enlarged view of yet a further example of a portion of a fluid dispenser 230 is shown in FIG. 10. As can be seen in FIG. 10, fluid delivery assembly 232 of fluid dispenser 230 includes a manifold 234 that is configured to include a plurality of differently slanted fluid passageways 236, 238, 240, and 242 each of which is configured to have a different angle relative to member 244 as shown. Fluid delivery assembly 232 additionally includes a plurality of slots 246, 248, 250, and 252 each of which is coupled to a different respective fluid passageway 236, 238, 240, and 242 of manifold 234 to conduct fluid from fluid passageways 236, 238, 240, and 242 towards orifices 254 of member 244. In this example, slots 246, 248, 250, and 252 are configured to have a substantially similar shape. Additionally, in this example, fluid passageway 236 is configured to have a greater cross-sectional width adjacent slot 246 than fluid passageways 238, 240, and 242 adjacent respective slots 248, 250, and 252, as generally indicated by double arrows 256 and 258. Further, in this example, cross-sectional width 256 of fluid passageway 236 is configured to be less than cross-sectional width 260 to help facilitate conveyance of bubbles through fluid passageway 236.
Although several examples have been described and illustrated in detail, it is to be clearly understood that the same are intended by way of illustration and example only. These examples are not intended to be exhaustive or to limit the invention to the precise form or to the exemplary embodiments disclosed. Modifications and variations may well be apparent to those of ordinary skill in the art. For example, in another embodiment, actuators 118, 120122, and 124 may be transducers, instead of resistors, that are energized to vibrate which forms drops that are ejected from orifices 102, 104, 106, and 108. As another example, the cross-sectional width of each of the slots can be configured based on the particular fluid passageway to which it is coupled such that the cross-sectional width of slots is relatively narrower for those fluid passageways that have a larger angle relative to the member and that is relatively wider for those fluid passageways that have a smaller angle relative to the member. As a further example, the bubble purging assembly is designed to also remove any bubbles arising in the slots of the fluid delivery system in addition to any of those arising in the fluid chambers. The spirit and scope of the present invention are to be limited only by the terms of the following claims.
Additionally, reference to an element in the singular is not intended to mean one and only one, unless explicitly so stated, but rather means one or more. Moreover, no element or component is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.