Patent Application
20210008875
Printing or dispensing devices may cause an amount of fluid to be deposited either onto the surface of a substrate or into wells contained within a substrate. Some printing devices implement an ejection chamber formed within a fluid ejection die that ejects an amount of fluid out of a nozzle and onto a predetermined location on the substrate. This ejection may be caused by any type of ejection device including a piezoelectric device or a resistive device.
The accompanying drawings illustrate various examples of the principles described herein and are part of the specification. The illustrated examples are given merely for illustration, and do not limit the scope of the claims.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings.
Inkjet printing devices may implement a resistive device and/or a piezoelectric device to eject an amount of fluid from the chamber housing these devices through a nozzle, and onto a substrate. A number of factors related to the ejection of the fluid as well as the parameters of the fluid ejection die may determine the quality of the images formed on the surface of the substrate for example, the amount of printing fluid ejected, how the fluid is ejected, how fast the fluid is ejected, the shape of the droplets of ejected print fluid, and other fluid ejection die parameters may determine the quality of images formed on the substrate. These factors may also influence the size and quality of drops delivered from a dispensing system.
Some of these parameters are a product of the physical devices within the fluid ejection die itself including the shape of the chamber formed within the silicon forming the fluid ejection die, the size of the resistive and/or piezoelectric devices used, the shape of the nozzle formed in the fluid ejection die, as well as other physical parameters. In an example, in order to understand how any given ejection device, chamber, and/or nozzle will deposit or eject an amount of printing fluid, a process may be initiated that starts with measuring the operating energy used to eject a measured drop weight of printing fluid. In this process, a representative number of fluid ejection dies would be subjected to such measurements prior to installation. The results of those measurements are then used to encode values onto all of the fluid ejection die produced based on those measurements from the representative fluid ejection dies. However, in this process, there would be no process that would account for variations among both the tested fluid ejection dies and the untested fluid ejection dies. The alternative would be to test every fluid ejection die produced which would result in extended production periods and extra production costs.
Alternatively, the operating characteristics of the fluid ejection dies and specifically the operating energy used, drop weight/volume/velocity of the ejected drops, and drop placement may be determined by measuring a firing pulse used to eject an amount of fluid. This process includes monitoring any temperature in the fluid ejection die as the operating energy is decremented. However, it has been shown through other analysis that this process does not work especially well on thermally efficient fluid ejection dies that use the energy received to a near maximum efficiency.
The present specification and the appended claims describe a method that includes measuring at least one physical parameter of at least one component of a plurality of components of a first fluid ejection die; and calculating an operating energy value to be used to operate the first fluid ejection die based on the at least one physical parameter of the at least one component.
The present specification also describes a computing device that includes a processor; and a data storage device communicatively coupled to the processor wherein the processor receives input of measurements of at least one physical parameter of at least one component of a plurality of components of a first fluid ejection die; and calculates an operating energy value to be used to operate the first fluid ejection die based on the at least one physical parameter of the at least one component.
The present specification further describes a computer program product for determining an operating energy of a fluid ejection die, the computer program product that includes a computer readable storage medium comprising computer usable program code embodied therewith, the computer usable program code to, when executed by a processor measure at least one physical parameter of at least one component of a plurality of components of a first fluid ejection die; calculate an operating energy value to be used to operate the first fluid ejection die based on the at least one physical parameter of the at least one component; and with a look-up table, determine an operating pulse, a voltage, and a pulse width used to operate the first fluid ejection die based on the calculated operating energy value
As used in the present specification and in the appended claims, the term “operating energy” is meant to be understood as any energy used to eject a fluid from a fluid ejection die. The terms firing energy may be used in connection with the term operating energy and may, in some examples, be synonymous with the term operating energy. In an example, the operation energy may include the electrical energy used to fire the resistive devices in the fluid ejection die. In an example, the operating energy may include the electrical energy used to manipulate a piezoelectric device within the fluid ejection die.
As used in the present specification and in the appended claims, the term “parameter” is mean to be understood as any value that characterizes an element of a system. In some examples, parameters of the systems and devices described result in specific operating characteristics of the devices.
As used in the present specification and in the appended claims, the term “printing fluid” is meant to be understood as any fluid that may be ejected from a fluid ejection die. In an example, the printing fluid is an ink. In an example, the printing fluid is a biological fluid that may, in an example, comprise biological components such as cells.
As used in the present specification and in the appended claims, the term “nominal” is meant to be understood as an intended characteristic that varies from an actual characteristic. By way of example, a nominal dimension of a resistive device is a dimension described by manufacturing specifications for the resistive device, where as a manufactured resistive device may vary from the nominal dimension by an amount.
Turning now to the figures,
A fluid ejection die may include any number of elements. These elements may include, but are not limited to any number of passivation layers, any number of resistive devices, any number of piezoelectric devices, any number of nozzle plate layers, any number of bores formed into the nozzle plate to serve as nozzles through which the printing fluid is ejected, the number and length of metal traces formed within the fluid ejection dies, the volume of a print fluid chamber formed within the fluid ejection dies, the volume of the print fluid chambers relative to the size of the resistive devices and/or piezoelectric devices, the volume of any fluid flow paths within the fluid ejection die, any flow characteristics of a fluid through the fluid flow paths, among other parameters.
The method (100) may continue with calculating (110) an operating energy value to be used to operate the first fluid ejection die based on the at least one physical parameter of the at least one component. Any method may be used to calculate the operating energy described herein based on the measured physical parameters of the at least one component. In an example, the operating energy may be calculated using the following equation:
Energy=Energy0[(1+k
Where Energy0 is the nominal energy for a particular fluid ejection die design, kn is the proportionality constant changes in energy per change in film thickness n, and Δtn is the change in film thickness n from the nominal value for the design being measured (105). Eq. 1, in an example, may further include a term describing a measured size of the resistor: length, width, height. In an example, the calculations used by the method (100) may take into consideration thicknesses of the resistive devices/piezoelectric devices as well as any protective layers deposited over a top portion of the resistive devices/piezoelectric devices. Any deviations from a nominal value as a result of variations in the manufacturing process may further be considered in Eq. 1.
In an example, the method (100) may further include calculating a drop volume to be ejected from the fluid ejection die based on measured physical parameters. In this example, the drop volume may be calculated using the following equation:
Volume=Volume0[(1+kbΔb)] Eq. 2
Where Volume0 is the nominal drop volume for a particular fluid ejection die design, kb is the proportionality constant for changes in drop volume per change in bore dimension, and Δb is a change in a bore dimension from the nominal value for the design. In an example, Eq. 2 may include a term for the size of a resistive device. Where the values defining the size of the resistive device deviates from the nominal, it may be due to variations in the manufacturing process.
In an example, the method (100) may include implementing a look-up table to determine an operating pulse, a voltage, and a pulse width used to operate the fluid ejection die based on the calculated operating energy value. The look-up table may be maintained on a data storage device or may be separate from the data storage device. In an example, the calculated (110) operating energy value, the calculated drop volume, the operating pulse, the voltage, and the pulse width may all be stored on the data storage device. These values may be used by a processor during operation of the fluid ejection die. In an example, these values may be directly encoded on to a data storage device placed on the fluid ejection die. In an example, these values may be encoded on a data storage device that is coupled to a pen or a printing fluid supply. In an example, these values may by encoded onto a data storage device of a printing device when the fluid ejection die is a permanent part of the printing device. In an example, these values may be stored on a data storage device communicatively coupled to the fluid ejection die, pen, and/or the printing device over a network.
Additional physical parameters of the elements of the fluid ejection die may also affect the operation of the fluid ejection die and may also be measured and used in calculating the operating energy and/or drop volume described herein. These additional physical parameters include electrical conductivity, heat conductivity, and surface tension, among others. Again, each of these additional parameters as well as those parameters described herein may be used to help predict the operating energy, drop volume, and/or drop velocity as described herein.
The fluid ejection chamber (200) may have a certain number of dimensions associated with it. The fluid ejection chamber (200) may have a chamber length (230), a chamber width (235), and a chamber height (240). As described herein, the physical parameters including the chamber length (230), chamber width (235), and chamber height (240) may be measured. In an example, these measurements may be made while the fluid ejection die has been assembled.
In an example, these dimensions may be measured prior to assembly of the elements described herein. However, in the case of the fluid ejection chamber (200), the chamber length (230), chamber width (235), and chamber height (240) may be determined based on the physical dimensions of the elements forming the fluid ejection chamber (200). For example, the fluid ejection chamber (200) may be formed out of a number of layers: a first layer (245), a second layer (250), and a third layer (255). These layers (240, 245, 250) may each have their respective dimensions measured prior to assembly and the placement of these three layers (240, 245, 250) respective to each other. The physical dimensions of these layers (240, 245, 250) as well as their placement respective to each other may be used to help extrapolate the chamber length (230), the chamber width (235), and the chamber height (240). As a result, the volume of the fluid ejection chamber (200) may be determined. These measurements may be used in a calculation (
The fluid ejection chamber (200) may further include a resistive device (205). The resistive device (205) may also include physical parameters: a resistive device length (220), a resistive device width (225), and a resistive device height (260). These physical parameters (220, 225, 260) may be measured after fabrication of the resistive device (205). In an example, the physical parameters (220, 225, 260) of the resistive device (205) may be measured using any measuring device. The physical parameters (220, 225, 260) of the resistive device (205) may be measured and used to calculate (
In an example, the heating properties of the resistive device (205) may be affected by a number of protective layers (265, 270) covering the resistive device (205).
As described above, the operating energy value, drop volume, and/or drop velocity calculated (
Because the physical parameters (220, 225, 260, 245, 250, 255, 265, 270) described herein may be used to calculate (
In an example, the operating characteristics of a first fluid ejection die resulting from the measurements and calculations described herein may be used to determine an adjustment to the operation of a second fluid ejection die. In this example, the operating characteristics between any given manufactured fluid ejection die may be adjusted in order to match the operating characteristics of other manufactured fluid ejection dies. This adjustment of operating characteristics may be done by addressing the look-up-table described herein in order to determine how to alter, for example, a firing pulse to any given fluid ejection device within any fluid ejection die.
The computing device (300) includes a processor (305). The processor (305) may be one that can execute computer readable program code. Specifically, the processor (305) may execute computer-readable program code in the form of a measurement module (310) and a calculation module (315). The various modules within the computing device (300) comprise executable program code that may be executed separately. In this example, the various modules may be stored as separate computer program products. In another example, the various modules within the computing device (300) may be combined within a number of computer program products; each computer program product comprising a number of the modules.
The measurement module (310), when executed by the processor (305), may receive input of measurements of at least one physical parameter of at least one component of a plurality of components of a first fluid ejection die. As described above, these measurements may be taken before each of the components of the fluid ejection die are assembled together to form the fluid ejection die. The measurements taken may include physical dimension measurements of any of the components, electrical conductivity measurements of any of the components, and thermal conductivity of any of the components, among other measurements described herein.
The processor (305) may then execute the calculation module (315). The calculation module (315) may calculate an operating characteristic associated with the first fluid ejection die based on the at least one physical parameter of the at least one component. The operating characteristics may include an operating energy, a drop volume, a drop velocity, and/or a drop placement. In an example, the operating energy value may be calculated by the calculation module (315) using Equation 1 described herein. In an example, the drop volume may be calculated using Equation 2 described herein. Other equations and processes may be used by the calculation module (315) to derive any number of other operating characteristics and the present specification contemplates those other equations and processes.
The processor (305) may further cause the values associated with the operating characteristics to be stored on a data storage device associated, at least, with the components of the fluid ejection die from which the measurements were taken. In an example, the data storage device may be maintained on the fluid ejection die that has incorporated that component measured. In an example, the data storage device may be maintained on a printing device associated with the fluid ejection die that has incorporated that component measured.
The calculation module (315) and/or the processor (305) may further implement a look-up-table to, determine an operating pulse that includes a voltage and/or a pulse width used to operate the first fluid ejection die based on the calculated operating energy value. Although a look-up table is presented as an example in the present specification, the present specification contemplates the use of any type of data format and/or data device used to determine the operating pulse that includes the voltage and/or pulse width. These values in the look-up table may, therefore, also be maintained on the data storage device and may be used by a printing device during operation of the fluid ejection die. The use of the operating characteristics as well as the operating pulse, voltage, and/or pulse width allows the fluid ejection device to be operated at a most efficient state and allows the printing device to compensate for any drop volume and/or drop velocity variations among the die of any type of pen. Further, during operation, the accuracy of the ejected drops of fluid from the fluid ejection die may be increased. Where the fluid ejected is a printing fluid such as ink, this increases the quality of any printed image on a substrate. Where the fluid is a biological fluid, the accuracy in the amount ejected is improved providing better accuracy in biological testing procedures.
The computing device (300) may be utilized in any data processing scenario including, stand-alone hardware, mobile applications, through a computing network, or combinations thereof. Further, the computing device (300) may be used in a computing network, a public cloud network, a private cloud network, a hybrid cloud network, other forms of networks, or combinations thereof. In one example, the methods provided by the computing device (300) are provided as a service over a network by, for example, a third party. In this example, the service may comprise, for example, the following: a Software as a Service (SaaS) hosting a number of applications; a Platform as a Service (PaaS) hosting a computing platform comprising, for example, operating systems, hardware, and storage, among others; an Infrastructure as a Service (IaaS) hosting equipment such as, for example, servers, storage components, network, and components, among others; application program interface (API) as a service (APIaaS), other forms of network services, or combinations thereof. The present systems may be implemented on one or multiple hardware platforms, in which the modules in the system can be executed on one or across multiple platforms. Such modules can run on various forms of cloud technologies and hybrid cloud technologies or offered as a SaaS (Software as a service) that can be implemented on or off the cloud. In another example, the methods provided by the computing device (300) are executed by a local administrator. In any of these examples, the computing device (300) may be communicatively coupled to a data storage device in order to write to the data storage device those values calculated by the calculation module (315).
The computing device (300) may further include various hardware components. Among these hardware components may be a number of peripheral device adapters and a number of network adapters. These hardware components may be interconnected through the use of a number of busses and/or network connections. In one example, the processor, data storage device, peripheral device adapters, and a network adapter may be communicatively coupled via a bus. The hardware adapters in the computing device (300) enable the processor to interface with various other hardware elements, external and internal to the computing device (300). For example, the peripheral device adapters may provide an interface to input/output devices, such as, for example, display device, a mouse, or a keyboard. The peripheral device adapters may also provide access to other external devices such as an external storage device, a number of network devices such as, for example, servers, switches, and routers, client devices, other types of computing devices, and combinations thereof.
The present system and methods may also include a computer program product for determining an operating energy of a fluid ejection die. The computer program product may include a computer readable storage medium comprising computer usable program code embodied therewith. The computer usable program code, when executed by a processor, may measure at least one physical parameter of at least one component of a plurality of components of a first fluid ejection die. This may be accomplished using the measurement module (310) described herein. Execution of the computer usable program code may, when executed by the processor, calculate an operating energy value to be used to operate the first fluid ejection die based on the at least one physical parameter of the at least one component. This may be accomplished using the calculation module (315) described herein. Additionally, execution of the computing usable program code by the processor may allow the processor to, with a look-up table, determine an operating pulse, a voltage, and a pulse width used to operate the first fluid ejection die based on the calculated operating energy value.
In an example, a calculated operating energy value used to operate a first fluid ejection die may be associated with both a first material source of a first component used to manufacture the first component of the first fluid ejection die. In this example, the calculated operating energy may be used to adjust an operating energy of a second fluid ejection die so that the first and second fluid ejection dies has the same or similar operating characteristics during use.
Aspects of the present system and method are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to examples of the principles described herein. Each block of the flowchart illustrations and block diagrams, and combinations of blocks in the flowchart illustrations and block diagrams, may be implemented by computer usable program code. The computer usable program code may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the computer usable program code, when executed via, for example, the processor (305) of the computing device (300) or other programmable data processing apparatus, implement the functions or acts specified in the flowchart and/or block diagram block or blocks. In one example, the computer usable program code may be embodied within a computer readable storage medium; the computer readable storage medium being part of the computer program product. In one example, the computer readable storage medium is a non-transitory computer readable medium.
The specification and figures describe a method to calculate an operating energy, drop volume, drop velocity, and/or drop placement from measurements of at least one component of a fluid ejection die. The use of the operating characteristics as well as the operating pulse, voltage, and/or pulse width allows the fluid ejection device to be operated at a most efficient state and allows the printing device to compensate for any drop volume and/or drop velocity variations among the die of any type of pen. Further, during operation, the accuracy of the ejected drops of fluid from the fluid ejection die may be increased. Where the fluid ejected is a printing fluid, this increases the quality of any printed image on a substrate. Where the fluid is a biological fluid, the accuracy in the amount ejected is improved providing better accuracy in biological testing procedures.
The preceding description has been presented to illustrate and describe examples of the principles described. This description is not intended to be exhaustive or to limit these principles to any precise form disclosed. Many modifications and variations are possible in light of the above teaching.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2018/021460 | 3/8/2018 | WO | 00 |
