Fluid ejection devices, such as printheads or dies in inkjet printing systems, typically use thermal resistors or piezoelectric material membranes as actuators within fluidic chambers to eject fluid drops (e.g., ink) from nozzles, such that properly sequenced ejection of ink drops from the nozzles causes characters or other images to be printed on a print medium as the printhead and the print medium move relative to each other. It is typically undesirable to hold ink within the fluidic chambers for prolonged periods of time without either firing or recirculating because the water or other fluid in the ink may evaporate. In addition, when pigment-based inks are held in the fluidic chambers for prolonged periods of time, the pigment may separate from the fluid vehicle in which the pigment is mixed. These issues may result in altered drop trajectories, velocities, shapes and colors, all of which can negatively impact the print quality of a printed image.
Features of the present disclosure are illustrated by way of example and not limited in the following figure(s), in which like numerals indicate like elements, in which:
For simplicity and illustrative purposes, the present disclosure is described by referring mainly to an example thereof. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be readily apparent however, that the present disclosure may be practiced without limitation to these specific details. In other instances, some methods and structures have not been described in detail so as not to unnecessarily obscure the present disclosure. As used herein, the terms “a” and “an” are intended to denote at least one of a particular element, the term “includes” means includes but not limited to, the term “including” means including but not limited to, and the term “based on” means based at least in part on.
Additionally, It should be understood that the elements depicted in the accompanying figures may include additional components and that some of the components described in those figures may be removed and/or modified without departing from scopes of the elements disclosed herein. It should also be understood that the elements depicted in the figures may not be drawn to scale and thus, the elements may have different sizes and/or configurations other than as shown in the figures.
Disclosed herein are printing systems and methods for controlling operation of the printing systems. Generally speaking, the printing systems and methods disclosed herein are directed to data driven recirculation of fluid in a fluid ejection device having a drop ejecting element and fluid circulating element, in which the fluid circulating element is in fluid communication with the drop ejecting element via a fluid circulation channel. More particularly, the printing systems may include a logic device that may be integrated into a fluid ejection assembly (or printhead) and is to receive an instruction data stream addressed to the drop ejecting element. The logic device may determine whether the instruction data stream includes an indication as to whether the drop ejecting element is to be energized. In response to a determination that the instruction data stream includes an indication that the drop ejecting element is to be energized, the logic device may energize the drop ejecting element. However, in response to a determination that the instruction data stream does not include an indication that the drop ejecting element is to be energized, the logic device may energize the fluid circulating element. In this regard, the logic device may energize the fluid circulating element without receiving a direct instruction to do so. Recirculation of the fluid through the fluid ejection device may therefore be data driven.
As discussed in greater detail herein below, energization of the fluid circulating element is intended to result in the circulation of fluid through a firing chamber, to thus keep the fluid in the firing chamber fresh, i.e., maintain desired fluid properties. In addition, in instances in which the fluid circulating element is a thermal resistor, energization of the fluid circulating element may also result in a warming of the fluid. In one regard, therefore, through implementation of the printing systems and methods disclosed herein, the fluid may be warmed through activation or energization of the fluid circulating element, in which a separate instruction to activate the fluid circulating element may not be needed. Instead, the logic device may activate the fluid circulating element when the logic device receives an instruction data stream that is addressed to the drop ejecting element but does not contain an instruction for the drop ejecting element to be energized, i.e., does not contain data for the drop ejecting element. In this regard, the amount of bandwidth required to enable warming by activating the fluid circulating element may be significantly lower than is needed to separately instruct the fluid circulating element to be energized for purposes of recirculation and/or warming. Moreover, and as discussed in greater detail herein below, activation of the fluid circulating element may further be controlled based upon various settings and conditions of the printing system and thus may not always be activated when the instruction data stream includes an instruction addressed to a drop ejecting element but contains no data.
With reference first to
The print media 118 may be any type of suitable sheet or roll material, such as paper, card stock, transparencies, Mylar, and the like. The nozzles 116 may be arranged in one or more columns or arrays such that properly sequenced ejection of ink from the nozzles 116 causes characters, symbols, and/or other graphics or images to be printed on print media 118 as the printhead assembly 102 and print media 118 are moved relative to each other.
The ink supply assembly 104 may supply fluid ink to the printhead assembly 102 and, in one example, includes a reservoir 120 for storing ink such that ink flows from the reservoir 120 to the printhead assembly 102. The ink supply assembly 104 and the printhead assembly 102 may form a one-way ink delivery system or a recirculating ink delivery system. In a one-way ink delivery system, substantially all of the ink supplied to the printhead assembly 102 is consumed during printing. In a recirculating ink delivery system, only a portion of the ink supplied to printhead assembly 102 is consumed during printing and ink that is not consumed during printing may be returned to the ink supply assembly 104.
In one example, the printhead assembly 102 and the ink supply assembly 104 are housed together in an inkjet cartridge or pen. In another example, the ink supply assembly 104 is separate from printhead assembly 102 and supplies ink to the printhead assembly 102 through an interface connection, such as a supply tube. In either example, the reservoir 120 of ink supply assembly 104 may be removed, replaced, and/or refilled. Where the printhead assembly 102 and the ink supply assembly 104 are housed together in an inkjet cartridge, the reservoir 120 includes a local reservoir located within the cartridge as well as a larger reservoir located separately from the cartridge. The separate, larger reservoir serves to refill the local reservoir. Accordingly, the separate, larger reservoir and/or the local reservoir may be removed, replaced, and/or refilled.
The mounting assembly 106 is to position the printhead assembly 102 relative to the media transport assembly 108, and the media transport assembly 108 is to position the print media 118 relative to the printhead assembly 102. Thus, a print zone 122 may be defined adjacent to the nozzles 116 in an area between the printhead assembly 102 and the print media 118. In one example, the printhead assembly 102 is a scanning type printhead assembly. In this example, the mounting assembly 106 includes a carriage for moving the printhead assembly 102 relative to the media transport assembly 108 to scan across the print media 118. In another example, the printhead assembly 102 is a non-scanning type printhead assembly. In this example, the mounting assembly 106 fixes the printhead assembly 102 at a prescribed position relative to the media transport assembly 108. Thus, the media transport assembly 108 may position the print media 118 relative to the printhead assembly 102.
The electronic controller 110 may include a processor, firmware, software, one or more memory components including volatile and non-volatile memory components, and other printer electronics for communicating with and controlling the printhead assembly 102, the mounting assembly 106, and the media transport assembly 108. The electronic controller 110 may receive data 124 from a host system, such as a computer, and may temporarily store the data 124 in a memory (not shown). The data 124 may be sent to the inkjet printing system 100 along an electronic, infrared, optical, or other information transfer path. The data 124 may represent, for example, a document and/or file to be printed. As such, the data 124 may form a print job for the inkjet printing system 100 and may include one or more print job commands and/or command parameters.
In one example, the electronic controller 110 controls the printhead assembly 102 for ejection of ink drops from the nozzles 116. Thus, the electronic controller 110 may define a pattern of ejected ink drops which form characters, symbols, and/or other graphics or images on the print media 118. The pattern of ejected ink drops may be determined by the print job commands and/or command parameters.
The printhead assembly 102 may include a plurality of printheads 114. In one example, the printhead assembly 102 is a wide-array or multi-head printhead assembly. In one implementation of a wide-array assembly, the printhead assembly 102 includes a carrier that carries the plurality of printheads 114, provides electrical communication between the printheads 114 and the electronic controller 110, and provides fluidic communication between the printheads 114 and the ink supply assembly 104.
In one example, the inkjet printing system 100 is a drop-on-demand thermal inkjet printing system in which the printhead 114 is a thermal inkjet (TIJ) printhead. The thermal inkjet printhead may implement a thermal resistor ejection element in an ink chamber to vaporize ink and create bubbles that force ink or other fluid drops out of the nozzles 116. In another example, the inkjet printing system 100 is a drop-on-demand piezoelectric inkjet printing system in which the printhead 114 is a piezoelectric inkjet (PIJ) printhead that implements a piezoelectric material actuator as an ejection element to generate pressure pulses that force ink drops out of the nozzles 116.
According to an example, the electronic controller 110 includes a flow circulation module 126 stored in a memory of the electronic controller 110. The flow circulation module 126 may be a set of instructions and may execute on the electronic controller 110 (i.e., a processor of the electronic controller 110) to control the operation of one or more fluid actuators integrated as pump elements within the printhead assembly 102 to control circulation of fluid within the printhead assembly 102, as described in greater detail herein below.
With reference now to
According to an example, a plurality of portions similar to the portion depicted in
In one example, the fluid ejection chamber 202 is formed in or defined by a barrier layer (not shown) provided on the substrate 206, such that the fluid ejection chamber 202 provides a “well” in the barrier layer. The barrier layer may be formed, for example, of a photoimageable epoxy resin, such as SU8.
According to an example, a nozzle or orifice layer (not shown) is formed or extended over the barrier layer such that a nozzle opening or orifice 210 formed in the orifice layer communicates with the fluid ejection chamber 202. The nozzle opening or orifice 210 may be of a circular, non-circular, or other shape.
The drop ejecting element 204 may be any device that is to eject fluid drops through the nozzle opening or orifice 210. Examples of suitable drop ejecting elements 210 include thermal resistors and piezoelectric actuators. A thermal resistor, as an example of a drop ejecting element, may be formed on a surface of a substrate (substrate 206), and may include a thin-film stack including an oxide layer, a metal layer, and a passivation layer such that, when activated, heat from the thermal resistor vaporizes fluid in a fluid ejection chamber 202, thereby causing a bubble that ejects a drop of fluid through the nozzle opening or orifice 210. A piezoelectric actuator, as an example of a drop ejecting element, may include a piezoelectric material provided on a moveable membrane communicated with a fluid ejection chamber 202 such that, when activated, the piezoelectric material causes deflection of the membrane relative to the fluid ejection chamber 202, thereby generating a pressure pulse that ejects a drop of fluid through the nozzle opening or orifice 210.
As illustrated in
The fluid circulating element 214 may form or represent an actuator to pump or circulate (or recirculate) fluid through the fluid circulation channel 212. The fluid circulating element 214 may thus be a thermal resistor or a piezoelectric actuator. In one regard, fluid from the fluid feed slot 208 may circulate (or recirculate) through the fluid circulation channel 218 and through the fluid ejection chamber 202 based on flow induced by the fluid circulating element 214. As such, fluid may circulate (or recirculate) between the fluid feed slot 208 and the fluid ejection chamber 202 through the fluid circulation channel 218. Circulating (or recirculating) fluid through the fluid ejection chamber 202 may help to reduce ink blockage and/or clogging in the fluid ejection device 200 as well as to keep the fluid in the fluid ejection chamber 202 fresh, i.e., reduce or minimize pigment separation, water evaporation, etc.
Also illustrated in
As illustrated in
An example of a fluid ejection device 200 having a 2:1 nozzle-to-pump ratio is shown in
In the examples illustrated in
With reference now to
Each of the drop ejecting elements 304a-304n and the fluid circulating elements 306a-306n may be assigned a respective address. As such, an instruction data stream 310 may include an address of one of the drop ejecting elements 304a-304n or the fluid circulating elements 306a-306n. In addition, the logic device 302 may send a firing signal, e.g., energize, a particular one of the drop ejecting elements 304a-304n or the fluid circulating elements 306a-306n based upon the address identified in a received data stream 310. Although individual drop ejecting elements 304a-304n and fluid circulating elements 306a-306n are depicted in
The drop ejecting elements 304a-304n and the fluid circulating elements 306a-306n may be organized into groups referred to as primitives. Each primitive may include a group of adjacent drop ejecting elements 304a-304n and their corresponding fluid circulating elements 306a-306n. A primitive may include any reasonably suitable number of drop ejecting elements 304a-304n and their corresponding fluid circulating elements 306a-306n, for instance, groups of six, eight, ten, twelve, fourteen, sixteen, and so on. By way of example, during a printing cycle, the logic device 302 may send a firing signal to one address in a primitive at a time.
In a particular example, the logic device 302 may receive an instruction data stream 310 that includes an address of a drop ejecting element 304a. The logic device 302 may receive the data stream 310, for instance, as data from a host 124 (
However, and according to an example, in response to a determination that the data stream 310 does not indicate that the drop ejecting element 304a is to eject a droplet of fluid, the logic device 302 may send a signal, e.g., energize, the fluid circulating element 306a corresponding to the drop ejecting element 304a. The logic device 302 may thus energize the fluid circulating element 306a even though the data stream 310 did not include an instruction to energize the fluid circulating element 306a. As such, instead of requiring a separate signal to energize the fluid circulating element 306a, the logic device 302 may use the signal intended for the drop ejecting element 304a to energize the fluid circulating element 306a. In one regard, through implementation of this feature, the bandwidth required to activate the fluid circulating element 306a may be significantly reduced as compared with requiring that the logic device 302 require receipt of a separate signal to activate the fluid circulating element 306a.
As discussed above, activation or energization of the fluid circulating element 306a may cause the fluid contained in the fluid ejection chamber 202 and the fluid circulation channel 212 to be circulated or recirculated without causing fluid in the fluid ejection chamber 202 from being ejected through a nozzle 210. Thus, in one regard, by energizing the fluid circulating element 306a when the corresponding drop ejecting element 304a is not energized, the fluid in the fluid ejection chamber 202 may be recirculated, which may keep that fluid fresh. In addition, in instances in which the fluid circulating elements 306a-306n are thermal resistors, energization of the fluid circulating elements 306a-306n may heat the fluid in the fluid circulation channel 212 as well as surrounding areas of the fluid circulating elements 306a-306n. Thus, in another regard, by energizing the fluid circulating elements 306a-306n when the corresponding drop ejecting elements 304a-304n are not energized, heat may still be applied to the fluid in the fluid circulation channels 212 and the fluid ejection chambers 202 to, for instance, maintain their temperatures above predetermined levels, which may improve nozzle performance.
As also shown in
With reference now to
The descriptions of the methods 400 and 500 are made with reference to the features depicted in
At block 402, a logic device 302 may receive a data stream 310 addressed to a drop ejecting element 304a of a fluid ejection device 200. As discussed above, the fluid ejection device 200 may have a fluid circulating element 306a (shown as element 214 in
At block 404, the logic device 302 may determine whether the data stream 310 indicates that the drop ejecting element 304a is to eject a droplet of fluid. For instance, the data stream 310 may include a bit or bits that identify the address of the drop ejecting element 304a and a data bit, in which the data bit may be set to 1 if the drop ejecting element 304a is to be energized and to 0 if the drop ejecting element 304a is not to be energized. Alternatively, the data bit may be set to 0 if the drop ejecting element 304a is to be energized and to 1 if the drop ejecting element 304a is not to be energized.
At block 406, in response to a determination that the data stream 310 does not indicate that the drop ejecting element 304a is to be energized, the logic device 302 may energize the fluid circulating element 306a corresponding to the drop ejecting element 304a. As discussed above, energizing the fluid circulating element 306a in this manner may reduce the amount of bandwidth required in a printing system 300 to recirculate fluid and/or heat fluid in a fluid ejection device 200.
Turning now to
At block 504, the logic device 302 may determine whether the data stream 310 indicates that the drop ejecting element 304a is to be energized, e.g., eject a droplet of fluid. Block 504 may be similar to block 404 in
At block 508, in response to a determination that the drop ejecting element 304a is not to be energized, the logic device 302 may determine whether a recirculation warming mode of the primitive in which the drop ejecting element 304a forms part is active. That is, for instance, the data input/settings 312 may indicate whether the logic device 302 is to implement warming of a primitive (or a portion of a die, the entire die, etc.) through energization of the fluid circulation elements 306a-306n. The recirculation warming mode may be set manually or automatically. When set manually, a user may input a setting to the logic device 302 as to whether the recirculation warming mode is active. In an automatic setting, a temperature sensor may be provided in or on the fluid ejection device 200 and the recirculation warming mode may be activated, for instance, when the temperature detected by the temperature sensor falls below a predetermined temperature level. Likewise, the recirculation warming mode may not be activated, for instance, when the temperature detected by the temperature sensor exceeds the predetermined temperature level.
In response to a determination that the recirculation warming mode is active, the logic device 302 may determine whether to override the active setting of the recirculation warming mode, as indicated at block 510. That is, the logic device 302 may determine whether to energize the fluid circulation element 306a even though the recirculation warming mode is active (block 508) and the drop ejecting element 304a is not to be energized (block 504). The logic device 302 may determine that the recirculation warming mode is not to be overridden at block 510, for instance, if the logic device 302 determines that the drop ejecting element 304a and/or the fluid circulating element 306a have not been energized at least a predetermined number of times within a predetermined period of time. In other words, the logic device 302 may determine that the fluid circulating element 306a is to be energized if the logic device 302 determines that the temperature of the fluid in the fluid ejection device 200 containing the drop ejecting element 304a may be at a temperature that is below a predetermined temperature, even though a temperature sensor located elsewhere has detected a different temperature.
In any case, in response to a determination that the activation of the recirculation warming mode is not to be overridden, the logic device 302 may energize the fluid circulating element 306a as indicated at block 512. However, if the logic device 302 determines that the active setting of the recirculation warming mode is to be overridden, the logic device 302 may not energize the fluid circulating element 306a, as indicated at block 514. The logic device 302 may determine that the active setting of the recirculation warming mode is to be overridden, for instance, if the logic device 302 determines that the drop ejecting element 304a and/or the fluid circulating element 306a have been energized at least a predetermined number of times within a predetermined period of time. In other words, the logic device 302 may determine that the fluid circulating element 306a is not to be energized if the logic device 302 determines that the temperature of the fluid in the fluid ejection device 200 containing the drop ejecting element 304a may be at a temperature that is above a predetermined temperature, even though a temperature sensor located elsewhere has detected a different temperature.
In another example, however, the logic device 302 may skip block 510 and may energize the fluid circulating element 306a at block 512 in response to a determination that the recirculation warming mode is active at block 508.
With reference back to block 508, in response to a determination that the recirculation warming mode is not active, the logic device 302 may determine whether to override the inactive setting of the recirculation warming mode, as indicated at block 516. That is, the logic device 302 may determine whether to energize the fluid circulating element 306a even though the recirculation warming mode is inactive (block 508) and the drop ejecting element 304a is not to be energized (block 504). The logic device 302 may determine that the inactive setting of the recirculation warming mode is not to be overridden at block 516, for instance, if the logic device 302 determines that the drop ejecting element 304a and/or the fluid circulating element 306a have not been energized at least a predetermined number of times within a predetermined period of time. In other words, the logic device 302 may determine that the fluid circulating element 306a is to be energized if the logic device 302 determines that the temperature of the fluid in the fluid ejection device 200 containing the drop ejecting element 304a may be at a temperature that is below a predetermined temperature, even though the recirculation warming mode is set to be inactive.
In any case, in response to a determination that the activation of the recirculation warming mode is to be overridden at block 516, the logic device 302 may energize the fluid circulating element 306a as indicated at block 512. However, if the logic device 302 determines that the inactive setting of the recirculation warming mode is not to be overridden, the logic device 302 may not energize the fluid circulating element 306a, as indicated at block 514. The logic device 302 may determine that the inactive setting of the recirculation warming mode is not to be overridden, for instance, if the logic device 302 determines that the drop ejecting element 304a and/or the fluid circulating element 306a have been energized at least a predetermined number of times within a predetermined period of time. In other words, the logic device 302 may determine that the fluid circulating element 306a is not to be energized if the logic device 302 determines that the temperature of the fluid in the fluid ejection device 200 containing the drop ejecting element 304a may be at a temperature that is above a predetermined temperature, even though a temperature sensor located elsewhere has detected a different temperature.
In another example, however, the logic device 302 may skip block 516 and may not energize the fluid circulating element 306a at block 514 in response to a determination that the recirculation warming mode is inactive at block 508.
The method 500 may end for the drop ejecting element 304a and the fluid circulating element 306a following either of blocks 512 and 514. In addition, the logic device 302 may receive another data stream containing an address of another drop ejecting element 304b and may implement the method 500 for that drop ejecting element 304b and its corresponding fluid circulating element 306b. The logic device 302 may cycle through the addresses of each of the drop ejecting elements 304b-304n prior to addressing the drop ejecting element 304a or the fluid circulating element 306a in a subsequent print cycle. In this regard, a sufficient amount of time may be afforded to the fluid ejection device 200 containing the drop ejecting element 304a and the fluid circulating element 306a to receive a new batch of fluid from the fluid slot 208.
Some or all of the operations set forth in the methods 400 and 500 may be contained as utilities, programs, or subprograms, in any desired computer accessible medium. In addition, the methods 400 and 500 may be embodied by computer programs, which may exist in a variety of forms both active and inactive. For example, they may exist as machine readable instructions, including source code, object code, executable code or other formats. Any of the above may be embodied on a non-transitory computer readable storage medium.
Examples of non-transitory computer readable storage media include computer system RAM, ROM, EPROM, EEPROM, and magnetic or optical disks or tapes. It is therefore to be understood that any electronic device capable of executing the above-described functions may perform those functions enumerated above.
Turning now to
The computer readable medium 608 may be any suitable medium that participates in providing instructions to the processor 602 for execution. For example, the computer readable medium 608 may be non-volatile media, such as an optical or a magnetic disk; volatile media, such as memory. The computer-readable medium 608 may also store machine readable instructions 612, which, when executed by the processor 602 may cause the processor 602 to perform some or all of the methods 400 and 500 depicted in
Although described specifically throughout the entirety of the instant disclosure, representative examples of the present disclosure have utility over a wide range of applications, and the above discussion is not intended and should not be construed to be limiting, but is offered as an illustrative discussion of aspects of the disclosure.
What has been described and illustrated herein is an example of the disclosure along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Many variations are possible within the spirit and scope of the disclosure, which is intended to be defined by the following claims—and their equivalents—in which all terms are meant in their broadest reasonable sense unless otherwise indicated.
The present application is the U.S. National Stage under 35 U.S.C. § 371 of International Patent Application No. PCT/U.S.2015/058406, filed Oct. 30, 2015, the disclosure of which is hereby incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2015/058406 | 10/30/2015 | WO | 00 |