Drive waveform provision system

Abstract

To provide a drive waveform provision system for providing setting value data to generate an appropriate drive waveform by minimizing a trouble and time required by a user of an inkjet head.SOLUTION: According to an embodiment, a drive waveform provision system includes a communication part for performing communication with an external terminal through a cloud, and a response part for creating response information to reception information from the external terminal. The response part provides the external terminal with an interface for receiving a use condition of an inkjet head, a physical property value of ink and inputs of a kind of a drive waveform at the request for providing setting value data of a drive waveform of the inkjet head. The response part provides the external terminal with the setting value data calculated on the basis of the use condition and the physical property value in the case that the kind of the drive waveform is a drive waveform for AL measurement. Also, the response part provides the external terminal with the setting value data calculated on the basis of the use condition, the physical property value and an actual measurement AL value in the case that the kind of the drive waveform is an optimal drive waveform.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION An embodiment of the present invention relates to a drive waveform providing system. [Background technology]

[0002] A liquid ejection device having an inkjet head generally forms an image on a print medium being transported by inputting a drive signal to a drive element such as a piezoelectric element of the inkjet head to eject a liquid such as ink from the nozzles. The drive signal is generated by a drive circuit of the inkjet head based on a drive waveform. The drive waveform is generated based on setting value data.

[0003] Conventionally, the drive waveform of an inkjet head is determined by, for example, having the user of the inkjet head evaluate the ink ejection while varying the parameters of the drive waveform using the ink that is actually used, thereby measuring, for example, the flight state of ink droplets and the print quality.

[0004] There is also a method for estimating AL from the ink's physical properties and determining the drive waveform without evaluating the ink ejection, by utilizing the correlation between the ink's physical properties and the inkjet drive waveform. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2021-160314 [Patent Document 2] Japanese Patent Publication No. 2022-95531 Summary of the Invention [Problem to be solved by the invention]

[0006] The method of determining the drive waveform by evaluating the ink ejection is time-consuming and laborious because the ejection evaluation is performed using actual ink and inkjet heads.Furthermore, the ink and its supply system must be discarded every time an ejection evaluation is performed, which is not only time-consuming and labor-intensive but also undesirable from an environmental perspective.

[0007] In the method of determining the drive waveform using correlation, the AL value estimated from the correlation may deviate significantly from the actual value, particularly for inks with distinctive physical properties such as high viscosity, making it impossible to determine an appropriate drive waveform.

[0008] The problem that the present invention aims to solve is to provide a drive waveform providing system that provides setting value data for generating an appropriate drive waveform while minimizing the effort and time required by the user of an inkjet head. [Means for solving the problem]

[0009] A drive waveform providing system according to an embodiment provides setting value data for a drive waveform of an inkjet head, and includes a communication unit that communicates with an external terminal via the cloud and a response unit that creates response information in response to received information received from the external terminal by the communication unit and provides the response information to the external terminal. In response to the received information requesting the provision of setting value data, the response unit provides the external terminal with response information for an interface that accepts input of inkjet head usage conditions, ink physical properties, and the type of drive waveform. When the type of drive waveform is a drive waveform for AL measurement, the response unit provides the external terminal with response information for setting value data calculated based on the usage conditions and physical properties. When the type of drive waveform is an optimal drive waveform, the response unit provides the external terminal with response information for setting value data calculated based on the usage conditions, physical properties, and an actually measured AL value. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram showing an example of the configuration of a droplet ejection device that operates using setting value data provided by a drive waveform providing system according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing an example of the configuration of a head controller of the liquid ejection device shown in FIG. [Figure 3] FIG. 3 is a block diagram showing an example of the configuration of the inkjet head of the liquid ejection device shown in FIG. [Figure 4] FIG. 4 is a block diagram showing a second example of the configuration of the head controller of the liquid ejection device shown in FIG. [Figure 5] FIG. 5 is a block diagram showing a second example of the configuration of the inkjet head of the liquid ejection device shown in FIG. [Figure 6] FIG. 6 is a flowchart showing a procedure for selecting setting value data for an inkjet head using a conventional method. [Figure 7] FIG. 7 is a block diagram showing the functional configuration of a driving waveform providing system according to the embodiment. [Figure 8] FIG. 8 is a block diagram showing the functional configuration of a web server of the driving waveform providing system shown in FIG. [Figure 9] FIG. 9 is a block diagram showing the functional configuration of the authentication server of the driving waveform providing system shown in FIG. [Figure 10] FIG. 10 is a block diagram showing the functional configuration of the application server and the web API server of the driving waveform providing system shown in FIG. [Figure 11] FIG. 11 is a block diagram showing the functional configuration of a database server of the driving waveform providing system shown in FIG. [Figure 12] FIG. 12 is a block diagram showing the hardware configuration of a computer that constitutes the driving waveform providing system shown in FIG. [Figure 13] FIG. 13 is a flowchart showing the flow of processing of a set value data calculation program executed by the driving waveform providing system. [Figure 14] FIG. 14 shows a UI screen for inputting parameters that is displayed on the screen of a PC. [Figure 15] FIG. 15 is a diagram showing a correlation formula between ink specific gravity and AL. [Figure 16] FIG. 16 is a functional block diagram showing the process from input of parameters to output of setting value data. [Figure 17] FIG. 17 is a flowchart showing the process flow from input of parameters to output of setting value data. [Figure 18] FIG. 18 is a diagram showing an example of a drive waveform for the AL value. [Figure 19] FIG. 19 is a graph showing an example of the relationship between the measured AL and the ejection velocity. DETAILED DESCRIPTION OF THE INVENTION

[0011] A drive waveform providing system according to an embodiment will be described below with reference to the drawings. The drive waveform providing system receives parameters related to an inkjet head and ink from an external terminal via the cloud, estimates a drive waveform for the inkjet head based on the received parameters, calculates setting value data for generating the estimated drive waveform, and provides the calculated setting value data to the external terminal via the cloud.

[0012] Here, the set value data is digital data, and the drive waveform is a digital waveform pulse. Hereinafter, the set value data for generating the drive waveform may be simply referred to as drive waveform set value data, or simply as drive waveform or set value data.

[0013] The external terminal generates a drive waveform for the inkjet head from the received setting value data, generates an analog drive signal from the generated drive waveform to drive the drive element of the inkjet head, and drives the inkjet head by applying the generated drive signal to the drive element.

[0014] Before describing the drive waveform providing system, a liquid ejection apparatus that operates using setting value data provided by the drive waveform providing system will be described below.

[0015] (Liquid discharge device) 1 is a block diagram showing an example of the configuration of a liquid ejection apparatus 10 that operates using setting value data provided by a drive waveform providing system according to an embodiment. The liquid ejection apparatus 10 is, for example, an inkjet recording apparatus. However, the liquid ejection apparatus 10 is not limited to this, and may be another apparatus such as a copier.

[0016] The liquid ejection device 10 performs various processes such as image formation while transporting a print medium, which is a recording medium.

[0017] The liquid ejection device 10 includes a control unit 11, a display 14, an operation unit 15, a communication interface 16, a transport motor 21, a motor drive circuit 22, a pump 23, a pump drive circuit 24, a plurality of inkjet heads 25, a head controller 26, a system bus 27, and a power supply circuit 28. The liquid ejection device 10 also includes a transport mechanism, a paper feed cassette, a paper discharge tray, etc., which are not shown. Note that in the drawings, the interface is abbreviated as "IF."

[0018] The power supply circuit converts AC power supplied from a commercial power source into DC power, and supplies the DC power to each component in the liquid ejection device .

[0019] The system bus 27 is a communication path between the control unit 11, the display 14, the operation unit 15, the communication interface 16, the motor drive circuit 22, the pump drive circuit 24, and the head controller 26. The control unit 11, the display 14, the operation unit 15, the communication interface 16, the motor drive circuit 22, the pump drive circuit 24, and the head controller 26 are able to send and receive information, data, addresses, control signals, commands, responses, etc. via the system bus 27.

[0020] The control unit 11 performs various controls on the liquid ejection device 10. The control unit 11 includes a processor 12 and a memory 13. The processor 12 is an arithmetic element that executes arithmetic processing. The processor 12 performs various processes based on, for example, programs stored in the memory 13 and data used in the programs. The memory 13 stores the programs, data used in the programs, etc. in a rewritable manner.

[0021] The display 14 is, for example, a display device such as a liquid crystal display, etc. The display 14 displays an image in response to a video signal input from the processor 12, a graphic controller (not shown) for performing image processing, etc.

[0022] The operation unit 15 has an operation member that generates an operation signal based on a user's operation. The operation member may be, for example, a touch sensor, a numeric keypad, a power key, a paper feed key, various function keys, a keyboard, or the like. The touch sensor may be, for example, a resistive touch sensor or a capacitive touch sensor. The touch sensor acquires information indicating a specified position within a certain area. The touch sensor may also be used as a touch panel that is disposed on the top surface of the display 14 and integrated with it. In this case, the touch sensor generates a signal that indicates the touched position on the screen displayed on the display 14.

[0023] The communication interface 16 is an interface for communicating with external devices. The communication interface 16 is used, for example, for communication with an external terminal 30 that transmits print data and register values ​​of setting data to the liquid ejection device 10. The communication interface 16 communicates with the external terminal 30 via a wired or wireless network, for example, a LAN (Local Area Network). The external terminal 30 is a control server, a PC, or the like that controls the liquid ejection device 10.

[0024] The transport motor 21 rotates to operate transport members of a transport mechanism (not shown) for transporting the print medium. The transport members include a transport belt that transports the print medium, multiple rollers (drive rollers and driven rollers) around which the transport belt is stretched, and guides. The transport motor 21 rotates the drive roller to move the transport belt that holds the print medium. The print medium moves along a transport path defined by guides arranged near the transport belt.

[0025] The motor drive circuit 22 is a circuit that drives the transport motor 21. The motor drive circuit 22 drives the transport motor 21 in accordance with a transport control signal input from the control unit 11. The motor drive circuit 22, the transport motor 21, and the transport mechanism transport the print medium taken out from a paper feed cassette (not shown) via multiple inkjet heads 25 to an output tray (not shown). The paper feed cassette is a cassette that stores multiple print media. The output tray is a tray that stores the print media discharged from the liquid ejection device 10.

[0026] The pump 23 supplies ink from an ink tank through an ink supply path to a pressure chamber of the inkjet head 25. The pump 23 is disposed on the ink supply path, which is made up of a tube (not shown) that connects the ink tank and the pressure chamber of the inkjet head 25.

[0027] The pump drive circuit 24 drives the pump 23 in accordance with an ink supply control signal input from the processor 12. The pump 23 supplies ink from an ink tank to a pressure chamber of the inkjet head 25.

[0028] The inkjet head 25 is an image forming unit that ejects ink onto a print medium to form an image. Although not shown, the inkjet head 25 includes actuators, which are driving elements such as piezoelectric elements that eject ink from nozzles, sensors for detecting ink temperature, and a drive circuit for driving the actuators. The inkjet head 25 forms an image by ejecting ink onto a print medium transported by a transport mechanism based on a drive power source and control signals supplied from a head controller 26. A plurality of inkjet heads 25 are provided, each corresponding to a different ink color, such as cyan, magenta, yellow, and black.

[0029] The liquid ejection device 10 receives print data and register values ​​of setting value data from the external terminal 30 via the communication interface 16 and stores them in the memory 13. When setting (configuring) the inkjet head 25, the processor 12 reads the print data and register values ​​of setting value data from the memory 13 and transmits them to the head controller 26.

[0030] The head controller 26 is a circuit that controls the multiple inkjet heads 25 based on the print data and the register values ​​of the setting data. The head controller 26 supplies multiple drive voltages to the inkjet heads 25 based on the register values ​​of the setting data. The head controller 26 also generates control signals based on the print data. The head controller 26 supplies the drive voltages and control signals to the inkjet heads 25 to operate actuators in the inkjet heads 25, thereby ejecting ink from the nozzles of the inkjet heads 25 and forming an image on the print medium.

[0031] (First configuration example of head controller and inkjet head) 2 and 3, a first configuration example of the head controller 26 and inkjet head 25 of the liquid ejection device 10 will be described. Fig. 2 is a block diagram showing the first configuration example of the head controller 26 of the liquid ejection device 10. Fig. 3 is a block diagram showing the first configuration example of the inkjet head 25 of the liquid ejection device 10.

[0032] (head controller) The head controller 26 has a bus bridge 261, a setting value data buffer 262, a print data buffer 263, a control signal generation unit 264, and a drive control unit 265. The drive control unit 265 has a setting value data transfer unit 266, a print data transfer unit 267, and a control signal transfer unit 268.

[0033] The setting value data is input from the system bus 27 to the setting value data buffer 262 via the bus bridge 261. The setting value data buffer 262 temporarily stores the setting value data, performs necessary processing on the setting value data as appropriate, and outputs the setting value data to a setting value data transfer unit 266 of the drive control unit 265. The setting value data transfer unit 266 transfers the setting value data to the inkjet head 25.

[0034] Print data is input from system bus 27 to print data buffer 263 via bus bridge 261. Print data buffer 263 temporarily stores the print data, processes it as needed, and outputs it to print data transfer unit 267 of drive control unit 265. Print data transfer unit 267 transfers the print data to inkjet head 25.

[0035] The control signal generation unit 264 generates a control signal for the inkjet head 25 and outputs it to a control signal transfer unit 268 of the drive control unit 265. The control signal includes a clock signal for determining operation timing, etc. The control signal generation unit 264 also generates a drive voltage to be supplied to the inkjet head 25 and outputs it to the control signal transfer unit 268 of the drive control unit 265. The control signal transfer unit 268 transfers the control signal and drive voltage to the inkjet head 25.

[0036] (inkjet head) The inkjet head 25 has a driver IC 251 and an actuator group 256. The actuator group 256 has a plurality of actuators. Each actuator is a driving element that expands and contracts a pressure chamber that contains ink, and ejects ink droplets from a nozzle that communicates with the pressure chamber. For example, each actuator is a piezoelectric driving element made of PZT (lead zirconate titanate).

[0037] The driver IC 251 is a drive circuit for the inkjet head 25. More specifically, the driver IC 251 is a drive circuit that drives the actuator group 256. The driver IC 251 has a drive signal generation circuit 252 and a data processing circuit 255. The drive signal generation circuit 252 has a drive waveform generation circuit 253 and an analog switch circuit 254.

[0038] The drive signal generation circuit 252 receives set value data from the set value data transfer unit 266. The data processing circuit 255 receives print data from the print data transfer unit 267, and receives a control signal and a drive voltage from the control signal transfer unit 268. The data processing circuit 255 supplies the drive voltage to the drive signal generation circuit 252. The data processing circuit 255 also generates a control signal for the drive signal generation circuit 252 based on the print data and the control signal, and outputs the control signal to the drive signal generation circuit 252. Under the control of the data processing circuit 255, the drive signal generation circuit 252 generates an analog drive signal from the set value data input from the set value data transfer unit 266, and outputs the drive signal to the actuator group 256.

[0039] More specifically, the analog switch circuit 254 has a plurality of switch elements, and the data processing circuit 255 supplies drive voltages of a plurality of levels to the plurality of switch elements in the analog switch circuit 254. The drive waveform generation circuit 253 generates a digital drive waveform in accordance with the set value data and print data, and outputs the drive waveform to the analog switch circuit 254. The analog switch circuit 254 generates an analog drive signal by selectively turning on one of a plurality of switch elements to which different drive voltages are supplied in accordance with the input digital drive waveform. The driver IC 251 outputs the drive signal to the actuator group 256.

[0040] Each actuator of the actuator group 256 operates in accordance with a drive signal input from the driver IC 251, expanding and contracting a pressure chamber that contains ink, and ejecting ink droplets from the nozzle.

[0041] (Second configuration example of head controller and inkjet head) A second configuration example of the head controller 26 and inkjet head 25 of the liquid ejection device 10 will be described below with reference to Figures 4 and 5. Figure 4 is a block diagram showing a second configuration example of the head controller 26 of the liquid ejection device 10. Figure 5 is a block diagram showing a second configuration example of the inkjet head 25 of the liquid ejection device 10. In Figures 4 and 5, components with the same reference numerals as those shown in Figures 2 and 3 are similar components, and detailed description thereof will be omitted. The following description will focus on the differences.

[0042] (head controller) The head controller 26 has a bus bridge 261, a setting value data buffer 2621, a print data buffer 263, a control signal generation unit 264, and a drive control unit 2651. The drive control unit 2651 has a drive waveform generation circuit 2661, a print data transfer unit 267, and a control signal transfer unit 268.

[0043] The setting value data is input from the system bus 27 via the bus bridge 261 to the setting value data buffer 2621. The setting value data buffer 2621 temporarily stores the setting value data, performs necessary processing on the setting value data as appropriate, and outputs the setting value data to the drive waveform generation circuit 2661 of the drive control unit 2651. The drive waveform generation circuit 2661 generates a digital drive waveform in accordance with the setting value data and outputs the drive waveform to the inkjet head 25.

[0044] (inkjet head) The inkjet head 25 has a driver IC 2511 and an actuator group 256. The actuator group 256 has a plurality of actuators. Each actuator is a driving element that expands and contracts a pressure chamber that contains ink, and ejects ink droplets from a nozzle that communicates with the pressure chamber.

[0045] The driver IC 2511 is a drive circuit for the inkjet head 25. More specifically, the driver IC 2511 is a drive circuit that drives the actuator group 256. The driver IC 2511 has an analog switch circuit 2521 and a data processing circuit 2551. The analog switch circuit 2521 receives a digital drive waveform from a drive waveform generation circuit 2661. The data processing circuit 2551 receives print data from a print data transfer unit 267 and a control signal and a drive voltage from a control signal transfer unit 268. The data processing circuit 2551 supplies a drive voltage to the analog switch circuit 2521. More specifically, the analog switch circuit 2521 has multiple switch elements, and the data processing circuit 2551 supplies drive voltages of multiple levels to the multiple switch elements in the analog switch circuit 2521. The data processing circuit 2551 also generates a control signal for the analog switch circuit 2521 based on the print data and the control signal, and outputs the control signal to the analog switch circuit 2521. The analog switch circuit 2521 , under the control of the data processing circuit 2551 , generates an analog drive signal from the digital drive waveform input from the drive waveform generation circuit 2661 , and outputs the drive signal to the actuator group 256 .

[0046] Specifically, the analog switch circuit 2521 generates an analog drive signal by selectively turning on one of a plurality of switch elements to which different drive voltages are supplied. The driver IC 2511 outputs the drive signal to the actuator group 256.

[0047] Each actuator of the actuator group 256 operates in accordance with a drive signal input from a driver IC 2511, expanding and contracting a pressure chamber that contains ink, and ejecting ink droplets from the nozzle.

[0048] (Setting value data selection using conventional methods) Next, a procedure for selecting setting value data for the inkjet head 25 using a conventional method will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the procedure for selecting setting value data for the inkjet head 25 using a conventional method.

[0049] In ACT11, the inkjet head 25 is driven by the basic drive waveform to eject ink and form an image on the print medium.

[0050] In ACT 12, the ink ejection is evaluated based on the size, speed, shape, etc. of the ejected ink droplets, and on the image formed on the printing medium, such as resolution, color reproducibility, clarity, and dot position accuracy.

[0051] In ACT13, the evaluation results are checked. For example, the evaluation results are checked by converting each of the above parameters into a numerical value and comparing the numerical value with a threshold value. For example, if the numerical value of each parameter is deemed better than the threshold value, the evaluation result is deemed OK, and if not, the evaluation result is deemed NG.

[0052] If the evaluation result of the check in ACT 13 is NG (No in ACT 13), the drive waveform is reselected in ACT 14. Next, in ACT 15, the inkjet head 25 is driven using the reselected drive waveform to eject ink and form an image on the printing medium. After that, the operations in ACT 12 and ACT 13 are performed.

[0053] That is, in ACT13, the operations of ACT14, ACT15 and ACT12 are repeated until the evaluation result becomes OK.

[0054] If the evaluation result is OK as a result of the check in ACT13 (Yes in ACT13), then in ACT16 the drive waveform at that time is recognized as the target drive waveform, and the setting value data that generates that drive waveform is selected as the target setting value data.

[0055] (Functional configuration of the driving waveform providing system) Next, the functional configuration of the drive waveform providing system 50 will be described with reference to Fig. 7. Fig. 7 is a block diagram showing the functional configuration of the drive waveform providing system 50 according to an embodiment. The drive waveform providing system 50 is configured from a server and the like on the cloud. In other words, the drive waveform providing system 50 can also be said to be a drive waveform providing server.

[0056] The driving waveform providing system 50 includes a web server 51, an authentication server 52, a firewall 53, an application server 54, a web API server 55, a database server 56, and a database 57. In the drawings, the application server is abbreviated as "AP server" and the database is abbreviated as "DB." The abbreviation for "DB" is not limited to that shown in FIG. 7.

[0057] The web server 51 is the first point of entry for access from the external terminal 30 to the driving waveform providing system 50, and provides a user interface for the external terminal 30. A block diagram showing the functional configuration of the web server 51 is shown in FIG. 8. The web server 51 has a communication function and a user interface providing function. The web server 51 also has a user interface database as a dedicated database in the database 57. Note that in the drawings, the user interface is abbreviated as "UI." In the following description, the user interface may also be abbreviated as "UI." The web server 51 provides a user interface to the external terminal 30, i.e., the PC 31 or the control server 32, and, via this user interface, interacts with each server (the authentication server 52, the application server 54, the web API server 55, and the database server 56) and the database 57 to receive requests from the external terminal 30 and return responses to those requests to the external terminal 30.

[0058] In one example, the external terminal 30 is a PC 31 that controls the liquid ejection device 10. The PC 31 is a user PC or an administrator PC. In this case, the user or administrator operating the PC 31 sends a request to a web server 51, for example, by HTTPS communication, through a user interface screen (UI screen) of a web application (for example, a web browser) displayed on the PC 31, and receives a response from the web server 51. The UI screen of the web application is created using, for example, HTML, CSS, JavaScript (registered trademark), etc.

[0059] In another example, the external terminal 30 is a control server 32 that controls the liquid ejection device 10. In this case, the control server 32 sends a request to a web server 51 using an API published as a web API, and receives a response from the web server 51.

[0060] The database 57 stores various data. The database server 56 manages the database 57. In response to requests from the authentication server 52, the application server 54, and the web API server 55, the database server 56 stores appropriate data in the database 57, or reads appropriate data from the database 57 and provides it to the authentication server 52, the application server 54, and the web API server 55.

[0061] A block diagram showing the functional configuration of the authentication server 52 is shown in Figure 9. The authentication server 52 has a login function. The authentication server 52 also has dedicated databases in its database 57, including a customer database, a user database, a whitelist, and a serial number database. In the drawing, the serial number is abbreviated as "S / N."

[0062] The authentication server 52 receives login information for the external terminal 30 from the web server 51, and permits login for authorized external terminals 30 through cooperation between the login function and a whitelist that holds information on authorized external terminals 30. Furthermore, for new external terminals 30, the authentication server 52 requests input of necessary information using the login function, identifies the access source domain, and permits login after registering the necessary information and the access source domain in the whitelist. The authentication server 52 outputs the authentication result to the firewall 53.

[0063] The authentication server 52 allows the administrator to perform operations with administrator privileges, such as registering users in the user database and accessing each database. After logging in, the authentication server 52 checks the input serial number of the inkjet head against the customer database and serial number database.

[0064] The firewall 53 protects the application server 54 and the web API server 55 from unauthorized access, etc. Based on the authentication result received from the authentication server 52, the firewall 53 permits authorized external terminals 30 to access the application server 54 and the web API server 55.

[0065] The application server 54 provides an execution environment for web applications. The web API server 55 provides APIs.

[0066] Fig. 10 is a block diagram showing the functional configuration of the application server 54 and web API server 55. The application server 54 and web API server 55 have a drive waveform provision function, an ink temperature and viscosity calculation engine, and a drive waveform estimation algorithm. In addition, the application server 54 and web API server 55 have dedicated databases in the database 57, including a coefficient database, a serial number database, an operation log database, and master data. The application server 54 and web API server 55 provide the administrator with an ink temperature and viscosity calculation engine update function and a drive waveform estimation algorithm update function.

[0067] The application server 54 and web API server 55 receive parameters, including the inkjet head 25 usage conditions and ink physical property values, from the logged-in and authenticated external terminal 30. The drive waveform providing function estimates the drive waveform for the inkjet head 25 from parameters, including the usage conditions and physical property values, using an ink temperature and viscosity calculation engine, a dedicated database, and other data analysis-based drive waveform estimation algorithm. The drive waveform estimation algorithm estimates the drive waveform using input variables such as the ink type, ink specific gravity, and inkjet head type. The drive waveform providing function provides setting value data for generating the estimated drive waveform. Furthermore, the drive waveform providing function corrects the setting value data based on the ink viscosity or temperature. Examples of ink types include UV-curable ink, oil-based ink, solvent ink, ceramic ink, and water-based ink.

[0068] Fig. 11 is a block diagram showing the functional configuration of the database server 56. The database server 56 has a data management function, a data update function, and a user management function. The database server 56 also has databases 57, including a coefficient database, a serial number database, a customer database, master data, a user database, an operation log database, master data, a user interface database, and a whitelist. The database server 56 also provides the administrator with a data update function and a user management function.

[0069] In the driving waveform providing system 50 configured in this manner, the web server 51 functions as a communication unit that communicates with the external terminal 30 via the cloud. The web server 51, application server 54, and web API server 55 also function as a response unit that cooperates with the database server 56 and database 57 to create response information in response to received information from the external terminal 30 and provide the response information to the external terminal 30.

[0070] The external terminal 30 transmits to the driving waveform providing system 50 parameters including the usage conditions of the inkjet head 25 of the liquid ejection device 10 and the physical properties of the ink, as well as a request for providing a driving waveform.

[0071] If the access from the external terminal 30 is appropriate, the drive waveform providing system 50 receives parameters via the web server 51, calculates setting value data for generating a drive waveform for the inkjet head 25 in the application server 54 or the web API server 55, and transmits the calculated setting value data to the external terminal 30 via the web server 51.

[0072] When the external terminal 30 is a PC 31 that controls the liquid ejection device 10, the application server 54 receives parameters including the usage conditions of the inkjet head 25 and the physical property values ​​of the ink, and outputs them to the database server 56. The database server 56 stores them in a database 57.

[0073] The application server 54 calculates setting value data for generating a drive waveform for the inkjet head 25. The application server 54 stores the setting value data in a database 57 via a database server 56. The application server 54 also transmits the setting value data to the PC 31 via a firewall 53 and a web server 51.

[0074] The PC 31 transmits the received setting value data to the liquid ejection device 10 automatically or under command of the user of the PC 31. The liquid ejection device 10 receives the setting value data via the communication interface 16 and stores it in the memory 13. When setting (configuring) the inkjet head 25, the processor 12 reads the setting value data from the memory 13 and transmits it to the head controller 26.

[0075] When the external terminal 30 is a control server 32 that controls the liquid ejection device 10, the web API server 55 performs the same operations as the application server 54 described above. That is, the web API server 55 receives parameters including the usage conditions of the inkjet head 25 and the physical property values ​​of the ink, and outputs them to the database server 56. The database server 56 stores the parameters in a database 57 via the database server 56.

[0076] The web API server 55 calculates setting value data for generating a drive waveform for the inkjet head 25. The web API server 55 stores the setting value data in a database 57 via a database server 56. The web API server 55 also transmits the setting value data to the control server 32 via the firewall 53 and the web server 51.

[0077] The control server 32 transmits the received setting value data to the liquid ejection device 10. The liquid ejection device 10 receives the setting value data via the communication interface 16 and stores it in the memory 13. When setting (configuring) the inkjet head 25, the processor 12 reads the setting value data from the memory 13 and transmits it to the head controller 26.

[0078] (Hardware configuration of the driving waveform providing system) The driving waveform providing system 50 may be configured by a computer. Hereinafter, the hardware configuration of a computer 60 that may configure the driving waveform providing system 50 will be described with reference to Fig. 12. Fig. 12 is a block diagram showing an example of the hardware configuration of the driving waveform providing system 50.

[0079] The computer 60 includes a processor 61 , a read only memory (ROM) 62 , a random access memory (RAM) 63 , an auxiliary storage device 64 , an input device 65 , an output device 66 , and a communication device 67 .

[0080] The processor 61, ROM 62, RAM 63, auxiliary memory device 64, input device 65, output device 66, and communication device 67 are electrically connected to each other via a bus 68, and are capable of sending and receiving data and information via the bus 68.

[0081] The processor 61 is configured by a general-purpose hardware processor including, for example, a CPU (Central Processing Unit), a GPU (Graphical Processing Unit), etc. The processor 61 controls the ROM 62, the RAM 63, the auxiliary storage device 64, the input device 65, the output device 66, and the communication device 67 as a whole.

[0082] The ROM 62 is a non-volatile memory that constitutes part of the main storage device. The ROM 62 non-temporarily stores a startup program required when the processor 61 is started. The processor 61 starts up by executing the program in the ROM 62. The ROM 62 is configured, for example, with an EPROM (Erasable Programmable Read Only Memory), and stores various startup settings in addition to the startup program.

[0083] The RAM 63 is a volatile memory that constitutes part of the main storage device. The RAM 63 temporarily stores programs required for processing by the processor 61 and data required for executing the programs. The processor 61 executes the programs in the RAM 63 to perform operations on the data in the RAM 63 and store the results of the operations in the RAM 63.

[0084] The auxiliary storage device 64 is configured by a non-volatile memory such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The auxiliary storage device 64 non-temporarily stores programs to be executed by the processor 61 and data required for executing the programs. The processor 61 loads the programs and data in the auxiliary storage device 64 into the RAM 63 and executes the programs to perform various functions.

[0085] For example, the input device 65 is configured with a keyboard, a mouse, a touch panel, etc. The input device 65 is not limited to this and may be configured with any other input device. For example, the output device 66 is configured with a display, etc. The output device 66 is not limited to this and may be configured with any other output device. The input device 65 and the output device 66 may be configured with an input / output device having the functions of both devices. For example, the input / output device is configured with a tablet, a disk drive, etc.

[0086] The communication device 67 has a function of transmitting and receiving data and information to and from the external terminal 30. For example, the communication device 67 has a receiving device and a transmitting device.

[0087] The program non-temporarily stored in the auxiliary storage device 64 is provided to the computer via, for example, a computer-readable recording medium on which the program is non-temporarily recorded. Such a recording medium is called a non-temporary computer-readable recording medium. For example, the non-temporary computer-readable recording medium is a disk such as a flexible disk, an optical disk (CD-ROM, CD-R, DVD-ROM, DVD-R, etc.), a magneto-optical disk (MO, etc.), or a semiconductor memory.

[0088] The program non-temporarily stored in the auxiliary storage device 64 is read into the auxiliary storage device 64 via the input device 65 through a disk drive if the recording medium is a disk, and then non-temporarily stored. Alternatively, the program may be stored in a server on a network, downloaded from the server, and non-temporarily stored in the auxiliary storage device 64.

[0089] Upon startup, the processor 61 executes a program in the ROM 62 and loads and starts the OS into the RAM 63. Under control of the OS, the processor 61 monitors input instructions, connections to external devices, and the like. Under control of the OS, the processor 61 also sets up a program area and a data area in the RAM 63. In response to an instruction to start the driving waveform providing system 50, the processor 61 loads the driving waveform providing program from the auxiliary storage device 64 into the program area of ​​the RAM 63, and loads data required for executing the driving waveform providing program from the auxiliary storage device 64 into the data area of ​​the RAM 63. The processor 61 calculates data in the data area in accordance with the driving waveform providing program and writes the calculation results to the data area. Through these operations, the processor 61, RAM 63, and auxiliary storage device 64 work together to execute the functions of the web server 51, authentication server 52, firewall 53, application server 54, web API server 55, database server 56, and database 57 of the driving waveform providing system 50.

[0090] The external terminal 30 may also be configured as a computer. The hardware configuration of the external terminal 30 is similar to the hardware configuration of the computer 60.

[0091] (Example of operation of the driving waveform providing system) Next, an example of the operation of the driving waveform providing system 50 will be described with reference to Fig. 13. Fig. 13 is a flowchart showing the processing flow of the example of the operation of the driving waveform providing system 50. Here, for convenience, the description will be given assuming that the external terminal 30 is a PC 31. In the flowchart of Fig. 13, the processing of the external terminal 30 (PC 31 and user) is shown on the left side, and the processing of the driving waveform providing system 50 is shown on the right side. In Fig. 13, the driving waveform providing system is abbreviated as "system".

[0092] When a user inputs an instruction to start using the driving waveform providing system 50 into PC31, PC31 sends a request to start using the driving waveform providing system 50, receives a UI screen for login processing from the driving waveform providing system 50, and in ACT21 displays the UI screen for login processing on the screen to prompt the user to perform the login processing.

[0093] When the user performs the login process, in ACT22, the driving waveform providing system 50 inquires about the user database using the authentication server 52 to perform user authentication process, and in ACT23, checks the authentication result.

[0094] A user database stores, for example, user IDs and passwords associated with those user IDs. Both user IDs and passwords are unique identification information. User IDs and passwords are associated one-to-one.

[0095] If the user ID and password entered on the UI screen for the login process match the user ID and password stored in the user database, the authentication server 52 determines that the authentication result is OK; if they do not match, the authentication result is NG.

[0096] If the authentication result is NG (No in ACT23), the driving waveform providing system 50 instructs the PC 31 to display an error message. In ACT24, the PC 31 displays the error message on the screen and waits for confirmation from the user. When the user confirms the error message, the PC 31 returns to the processing of ACT21 and again displays the UI screen for the login processing on the screen to prompt the user to perform the login processing.

[0097] If the authentication result is OK (Yes in ACT23), the driving waveform providing system 50 permits the login, and then instructs the PC 31 to display a UI screen for serial number input processing of the inkjet head 25. In ACT25, the PC 31 displays the UI screen for serial number input processing on the screen to prompt the user to input the serial number.

[0098] When the user inputs the serial number of the inkjet head 25, in ACT26, the driving waveform providing system 50 uses the authentication server 52 to query the serial number database and perform a serial number verification process, and in ACT27, checks the verification result.

[0099] The serial number database stores the serial numbers of the inkjet heads 25. Each serial number is associated with a corresponding inkjet head 25. For example, the serial number is registered in the serial number database when the inkjet head 25 is purchased.

[0100] If the serial number entered on the UI screen for the serial number input process matches any of the serial numbers registered in the serial number database, the authentication server 52 recognizes that the matching result is OK; if they do not match, the authentication server 52 recognizes that the matching result is NG.

[0101] If the collation result is NG (No in ACT27), the driving waveform providing system 50 instructs the PC 31 to display an error message. In ACT28, the PC 31 displays the error message on the screen and waits for confirmation from the user. When the user confirms the error message, the PC 31 returns to the processing in ACT25 and again displays the UI screen for the serial number input processing on the screen to prompt the user to input the serial number.

[0102] If the collation result is OK (Yes in ACT27), the driving waveform providing system 50 instructs the PC 31 to display a UI screen for parameter input processing. The UI screen for parameter input processing is an interface that accepts input of parameters including the operating conditions of the inkjet head 25, the physical properties of the ink, the measured AL value, and an instruction to provide setting value data for measuring the AL value. In ACT29, the PC 31 displays the UI screen for parameter input processing that accepts input of parameters on the screen, and prompts the user to input parameters.

[0103] The UI screen for parameter input processing is shown in Figure 14. The UI screen for parameter input processing includes a DB selection field, a head selection field, an ink selection field, an operating conditions selection field, an ink temperature and viscosity input field, a waveform selection field, a drive voltage input field, a waveform creation button, a register data creation button, and a head and waveform type and waveform value display field.

[0104] The DB selection field has options (S / N DB, Coefficient DB) to select whether to use the serial number database or the coefficient database, and either the S / N DB or the coefficient DB can be selected using the radio button or option button.

[0105] The head selection field includes a head type selection field, a serial number display field, and an AL rank selection field. The head type selection field allows the head type to be selected using a pull-down function. The serial number display field displays the serial number entered in the UI screen for the serial number input process displayed in ACT25. The AL rank field allows the AL rank to be selected using a pull-down function. AL (acoustic length) is half the time of the natural vibration period of the ink in the pressure chamber of the inkjet head 25, and is also called the pressure propagation time. AL has different values ​​depending on the inkjet head 25. Ranking is performed based on the AL value, and an AL rank is assigned.

[0106] The ink selection field includes an ink type selection field and an ink specific gravity input field. The ink type field allows you to select the ink type using a pull-down function. The ink specific gravity input field allows you to directly input the ink specific gravity value. In addition, the ink specific gravity input field displays a message prompting you to input the recommended range (0.70 to 3.0) in advance.

[0107] The usage condition selection field includes a drop number selection field and a frequency input field. The drop number selection field allows the drop number to be selected using a pull-down function. The drop number selection field may allow the drop number value to be directly input. The frequency input field allows the drive frequency value to be directly input. Furthermore, the frequency input field displays a message in advance prompting the user to input a value within the recommended range (1.0 to 30.0).

[0108] The ink temperature and viscosity input field includes a temperature and viscosity selection field, an input and display field, and an ink temperature and viscosity calculation input button. The temperature and viscosity selection field has options for recommended temperature, desired temperature, and desired viscosity, and users can select one of the recommended temperature, desired temperature, or desired viscosity using radio buttons or option buttons. The display content of the input and display field changes depending on the selection in the temperature and viscosity selection field. The ink temperature and viscosity calculation input button is a UI element that confirms the selection in the temperature and viscosity selection field and the input in the input and display field, and instructs the execution of calculations for ink temperature, viscosity, or both, based on those selections and input values.

[0109] In the example of Figure 14, in response to the selection of the desired temperature in the temperature / viscosity selection field, the input / display fields are displayed as follows: a display field for the ink temperature at a viscosity of 10 mPa·s, an input field for the desired ink temperature, and a display field for the viscosity at the desired ink temperature. In this case, the user enters the ink temperature in the input field for the desired ink temperature, and clicks the ink temperature / viscosity calculation input button to instruct the execution of the calculation. As a result, the calculation results are displayed in the display field for the ink temperature at a viscosity of 10 mPa·s and the display field for the viscosity at the desired ink temperature.

[0110] Also, for example, if the recommended temperature is selected in the temperature / viscosity selection field, a display field for the ink temperature at a viscosity of 10 mPa·s, a display field for the recommended ink temperature, and a display field for the viscosity at the recommended ink temperature are displayed as input / display fields, and the user can simply click the ink temperature / viscosity calculation input button to instruct the execution of the calculation without entering any input.As a result, the calculation results are displayed in the display field for the ink temperature at a viscosity of 10 mPa·s, the display field for the recommended ink temperature, and the display field for the viscosity at the recommended ink temperature.

[0111] The waveform selection field has options for estimated waveform, waveform for AL measurement, and optimal waveform, and users can select one of these options using radio buttons or option buttons. The estimated waveform option is a UI element that instructs the drive waveform providing system 50 to provide setting value data for a drive waveform estimated using an AL value estimated based on the ink's physical properties, etc. The AL measurement waveform option is a UI element that instructs the drive waveform providing system 50 to provide setting value data for a drive waveform used for AL measurement. The optimal waveform option has an input field for an actual measured AL value and is a UI element that instructs the drive waveform providing system 50 to provide setting value data for a drive waveform estimated using the input value in the actual measured AL value input field. In this case, the drive waveform estimated by the drive waveform providing system 50 includes the actual measured AL value as an input variable for the drive waveform estimation algorithm, and therefore can be said to be an optimal drive waveform or a drive waveform close to optimal for the inkjet head 25. For this reason, in the waveform selection field, an option that forms a triplet with the estimated waveform and waveform for AL measurement options is referred to as the optimal waveform. That is, the optimum waveform option is a UI element that instructs the drive waveform providing system 50 to provide the setting value data of the optimum drive waveform. When selecting the optimum waveform, it is essential to input the measured AL value in the input field.

[0112] The drive voltage input field allows input of a drive voltage value. The waveform creation button is a UI element that instructs the drive waveform providing system 50 to provide drive waveform setting value data. The register data creation button is a UI element that instructs the drive waveform providing system 50 to provide register data of drive waveform setting value data.

[0113] The head waveform type and waveform value display field displays the waveform type and its elements selected based on the various parameters described above, as well as the pulse value of the waveform value calculated based on the various parameters described above.

[0114] The user inputs ink physical property values ​​and inkjet head 25 usage conditions from the parameter input processing UI screen shown in Fig. 14. The ink physical property values ​​and inkjet head 25 usage conditions also include values ​​related to printing conditions and print quality, and are not limited to those shown on the parameter input processing UI screen. In other words, the parameter input processing UI screen is an example of a UI screen and may be changed as appropriate.

[0115] When the user has completed inputting the parameters and instructs the drive waveform providing system 50 to provide the setting value data of the drive waveform via the waveform creation button, or to provide the register data of the setting value data of the drive waveform via the register data creation button, in ACT30 the drive waveform providing system 50 performs an input parameter check process using the application server 54.

[0116] If the check result is NG (NG in ACT30), the driving waveform providing system 50 instructs the PC 31 to display an error message. In ACT31, the PC 31 displays the error message on the screen and waits for confirmation from the user. When the user confirms the error message, the PC 31 returns to the processing of ACT29 and displays a UI screen for parameter input processing on the screen to prompt the user to input parameters.

[0117] An example of a case where the check result is NG (NG in ACT30) is when the optimal waveform is selected in the waveform selection field on the UI screen for parameter input processing shown in FIG. 14, but no value is entered in the input field for the measured AL value.

[0118] If the check result is OK (OK in ACT30), the driving waveform providing system 50 performs calculation processing of the temperature and viscosity of the ink using the application server 54 in ACT32.

[0119] Next, in ACT33, the drive waveform providing system 50 uses the drive waveform estimation algorithm and a dedicated database to estimate the drive waveform of the inkjet head 25 based on the parameters inputted into the UI screen for the parameter input process shown in Figure 14, which is displayed on the PC 31 in ACT29, by the application server 54.

[0120] Here, if an estimated waveform is selected in the waveform selection field of the UI screen for the parameter input process shown in Figure 14, which is displayed on PC 31 in ACT 29, the drive waveform estimated by the drive waveform providing system 50 will be a drive waveform estimated by a drive waveform estimation algorithm from input variables including the estimated AL value. Also, if an AL measurement waveform is selected, the drive waveform estimated by the drive waveform providing system 50 will be a drive waveform for AL measurement estimated by a drive waveform estimation algorithm from input variables that do not include the actually measured AL value. Also, if an optimal waveform is selected, the drive waveform estimated by the drive waveform providing system 50 will be a drive waveform estimated by a drive waveform estimation algorithm from input variables including the actually measured AL value. This drive waveform is an optimal or close-to-optimal drive waveform for the inkjet head 25 because the actually measured AL value is reflected in the estimated result.

[0121] Next, in ACT34, the drive waveform providing system 50 calculates setting value data for generating a drive waveform using the application server 54. The drive waveform providing system 50 transmits the setting value data to the PC 31 using the web server 51. This completes the process of providing the drive waveform setting value data to the PC 31 by the drive waveform providing system 50.

[0122] (Correlation formula between ink specific gravity and AL) Figure 15 shows the correlation equation between ink specific gravity and AL. AL is determined by the ink and the inkjet head 25. As can be seen from this figure, there is a strong correlation between ink specific gravity and AL. Therefore, based on the relationship between this equation and the ink evaluation results from the head shipping inspection, the unique AL for each inkjet head 25 can be calculated. The head shipping inspection ink evaluation results are the results of AL measurements, drive voltage measurements, and print measurements of the inkjet head 25 using test ink during the shipping inspection of the inkjet head 25. In the following explanation, the test ink will be referred to as test ink. The AL of the inkjet head 25 measured using the test ink will be referred to as test ink AL. Unlike the test ink AL, the ink AL is the AL of the ink actually used. The ink AL is calculated by an estimate based on the test ink AL. Furthermore, in the following explanation, the drive voltage measured using the test ink will be referred to as the test ink voltage. Unlike the test ink voltage, the ink voltage is the drive voltage of the ink actually used. The ink voltage is calculated by an estimate based on the test ink voltage.

[0123] (Process functions from parameter input to setting value data output) Next, the process from inputting parameters to outputting setting value data will be described with reference to Fig. 16. Fig. 16 is a functional block diagram showing the process from inputting parameters to outputting setting value data. For convenience, the description here will be given assuming that the external terminal is PC 31 and its user.

[0124] In ACT41, parameters such as ink physical property values ​​(ink type, ink specific gravity, ink temperature, ink viscosity, etc.) and inkjet head 25 usage conditions (head type, head specific value, serial number, AL rank, head driving voltage, number of ejected drops, frequency, etc.) are entered on the head / ink input screen (head selection field, ink selection field, usage condition selection field, drive voltage input field on the UI screen shown in Figure 14).

[0125] In ACT42, parameters required for estimating a drive waveform (estimated waveform, AL measurement waveform, or optimum waveform) for which setting value data is desired to be provided are input on the waveform input screen (waveform selection field on the UI screen shown in FIG. 14).

[0126] ACT43 calculates waveform element values ​​based on the parameters entered on the head / ink input screen and waveform input screen. Waveform element value calculations include calling coefficients, calculating AL values, calculating boost (ejection speed amplification pulse) values, and calculating drive voltage values. Calculating waveform element values ​​first estimates the specific AL determined by the ink and inkjet head 25 from the ink type, ink specific gravity, inkjet head 25 usage conditions, and the ink specific gravity-AL relationship. Next, each waveform element value is estimated based on the calculation formula derived from the AL and ink evaluation result data.

[0127] Optionally, in ACT44, the desired temperature, three temperatures, and three viscosities are input on the temperature and viscosity input screen (the ink temperature and viscosity input field on the UI screen shown in Figure 14). Then, in ACT45, the temperature and viscosity are calculated based on the input parameters.

[0128] In ACT46, waveform value voltage correction is performed on the results of the waveform element value calculation and the temperature / viscosity calculation. In waveform value voltage correction, the waveform element value and drive voltage value are corrected based on the ink temperature under the operating conditions and the ink viscosity at that time. In other words, the calculation results of the temperature / viscosity calculation are used to perform corrections on the calculation results of the waveform element value calculation. Specifically, the viscosity value finally calculated in the temperature / viscosity calculation is used to correct the AL value, boost value, and drive voltage value.

[0129] In ACT47, each waveform value is calculated. In this calculation, each waveform value is calculated from the AL value and boost value. Specifically, the pulse time of all waveforms is estimated and calculated using a calculation formula that analyzes the ink evaluation result data using methods such as regression and classification.

[0130] In ACT48, register conversion is performed on the waveform values ​​to obtain set value data. That is, by converting the waveform values ​​into register data, set value data for generating a drive waveform for the inkjet head 25 is obtained. Finally, the set value data is output.

[0131] (Process flow from parameter input to setting value data output) Next, the process flow from inputting parameters to outputting setting value data will be described with reference to Fig. 17. Fig. 17 is a flowchart showing the process flow from inputting parameters to outputting setting value data. The process from inputting parameters to outputting setting value data is mainly performed by the application server 54.

[0132] In ACT51, the application server 54 transmits an instruction to display the UI screen for the parameter input processing shown in Fig. 14 to the PC 31. Upon receiving the instruction to display the UI screen for the parameter input processing, the PC 31 displays the UI screen for the parameter input processing on the screen to prompt the user to input parameters.

[0133] When the user inputs the appropriate parameters, in ACT52, the application server 54 obtains the ink's physical properties (ink type, ink specific gravity, ink temperature, ink viscosity, etc.), the inkjet head 25 usage conditions (head type, head specific values, serial number, AL rank, head drive voltage, number of ejected drops, frequency, etc.), the type of drive waveform for which the user desires to provide setting value data, etc.

[0134] Next, in ACT 53, the application server 54 performs an AL value estimation calculation. In the AL value estimation calculation, the AL value is estimated based on the ink type, ink specific gravity, usage conditions of the inkjet head 25, and the ink specific gravity-AL relational expression. AL is a value specific to the inkjet head 25 and is determined by the ink and the inkjet head 25.

[0135] Next, in ACT54, the application server 54 determines the type of drive waveform for which it desires to provide setting value data. Specifically, the application server 54 determines whether the waveform selected in the waveform selection field on the UI screen shown in Fig. 14 is a waveform for AL measurement, an estimated waveform, or an optimum waveform.

[0136] If the result of the determination in ACT54 is that the selected waveform is a waveform for AL measurement, the application server 54 proceeds to the process of ACT64.

[0137] If the result of the determination in ACT54 is that the selected waveform is an estimated waveform, the application server 54 proceeds to the process in ACT56.

[0138] Furthermore, if the determination result in ACT 54 is that the selected waveform is the optimum waveform, the application server 54 acquires the measured AL value in ACT 55. Specifically, the application server 54 acquires the input value in the input field for the measured AL value of the optimum waveform option in the waveform selection field on the UI screen shown in FIG.

[0139] In ACT56, the application server 54 performs a waveform element value estimation calculation. The application server 54 estimates and calculates each waveform element value based on a calculation formula derived from the AL specific to the inkjet head 25 and the ink evaluation result data. When the selected waveform is an estimated waveform, the application server 54 uses the AL value estimated and calculated in ACT53 as the AL value in the waveform element value estimation calculation, and when the selected waveform is an optimal waveform, the application server 54 uses the actually measured AL value obtained in ACT55.

[0140] Furthermore, in ACT 57, the application server 54 performs a drive voltage value estimation calculation, which estimates the drive voltage value from the head characteristic value, the ink specific gravity, and the ink viscosity.

[0141] In ACT58, the application server 54 checks whether the ink temperature and ink viscosity have been input. Specifically, the application server 54 checks the input contents in the ink temperature and viscosity input field on the UI screen shown in Fig. 14. If the ink temperature and ink viscosity have been input (if yes in ACT58), the process proceeds to ACT59. If the ink temperature and ink viscosity have not been input (if no in ACT58), the process proceeds to ACT63.

[0142] In ACT59, the application server 54 checks the input contents of the ink temperature and ink viscosity. If ink viscosity has been input (if viscosity has been input in ACT59), the process proceeds to ACT61 and ACT62. If ink viscosity has not been input (if only temperature has been input in ACT59), the process proceeds to ACT60.

[0143] In ACT60, the application server 54 estimates and calculates the ink viscosity from the ink temperature, and then proceeds to the processing of ACT61 and ACT62.

[0144] In ACT61, the application server 54 performs waveform element value correction. In the waveform element value correction, the waveform element value is corrected based on the ink temperature under the usage conditions and the ink viscosity at that ink temperature. Then, the process proceeds to ACT63.

[0145] Furthermore, in ACT 62, the application server 54 performs drive voltage value correction, which corrects the drive voltage value based on the ink temperature under the use conditions and the ink viscosity at that ink temperature.

[0146] In ACT 63, the application server 54 calculates each waveform value. In calculating each waveform value, the pulse time of all waveforms is estimated and calculated using a calculation formula obtained by analyzing the ink evaluation result data using a method such as regression or classification.

[0147] Next, in ACT64, the application server 54 performs drive waveform data conversion. In the drive waveform data conversion, the waveform value is converted into register data to obtain setting value data for generating the drive waveform of the inkjet head 25. Finally, the setting value data is output.

[0148] (Example of operation) An example of an operation for outputting setting value data from the UI screen of the parameter input process shown in FIG. 14 through the process of the flowchart in FIG. 17 will be described below.

[0149] The formula for deriving the input variable and output waveform value is derived through statistical processing of past measured data, and the output value is derived from a combination of the following multiple linear equations for the input value.

[0150] ax1 = minimum AL value of test ink + an1 - formula (1) ax2 = minimum AL value of test ink + an2 - formula (2) ay1=c11*ink specific gravity+c12 - Equation (3) ay2=c21*ink specific gravity+c22 - Equation (4) AL_slope=(ay2-ay1) / (ax2-ax1) - Equation (5) AL_intercept=ay1-AL_slope*ax1 - Equation (6) Test ink AL value = Test ink minimum AL value + Test ink AL rank value - Equation (7) Ink AL_value = AL_slope * Test ink AL value + AL_intercept - Equation (8) In the above formulas (1) and (2), ax1 and ax2 are the AL rank values ​​of the test ink for the head-specific value, and an1 and an2 are the AL rank values ​​of the test ink that are representative of each inkjet head 25.

[0151] In the above formulas (3) and (4), ay1 and ay2 are the AL values ​​for the input ink specific gravity for ax1 and ax2. c11, c12, c21, and c22 are coefficients determined by the head type and ink type, and are called up when the head type and ink type are input on the input screen in Figure 14.

[0152] An example of the values ​​of the constants and coefficients for the above combination of head type and ink type is an1=AL4, n2=AL6, c11=0.491, c12=1.128, c21=0.495, and c22=1.167.

[0153] Equations (1) and (2) are used to determine the relationship between the head-specific value and the AL value for the test ink, and equations (3) and (4) are used to determine the relationship between the head-specific value and the AL value for the ink specific gravity. Equations (5) and (6) are the slope and intercept of the equation used to determine the AL value using equations (1) to (4). Equation (7) is used to derive the AL value for the test ink for the AL rank value desired for the inkjet head 25, and equation (8) is used to derive the AL value for the input specific gravity using the AL_slope, AL_intercept, and AL value of the test ink determined using equations (5) to (7).

[0154] The boost values ​​are determined by coefficients c13, c14, c23, and c24, which are determined by the head type and ink type, and the boost values ​​for each head specific value are by1 and by2. by1=c13*ink specific gravity+c14 - Equation (9) by2=c23*ink specific gravity+c24 - Equation (10) Then, the AL value in equations (1) and (2) is taken as the x-axis, and by1 and by2 are taken as the y-axis, and the same calculation as for AL is performed.

[0155] Correction based on temperature and viscosity takes top priority when a viscosity value is entered, and is calculated as follows: Ink voltage = test ink voltage + voltage addition variable + voltage correction coefficient 1 * (ink viscosity - recommended viscosity value). In the above formula, the voltage addition variable is a variable determined by the head type, head specific value, and ink type, and voltage correction coefficient 1 is a coefficient that corrects the voltage value according to the viscosity value.

[0156] If there is no viscosity input but there is a temperature input, the formula is Ink voltage = Test ink voltage + Voltage addition variable + Voltage correction coefficient 2 * (Ink temperature in pressure chamber - Recommended ink temperature). In the above formula, Voltage correction coefficient 2 is a coefficient that corrects the voltage value according to the temperature value.

[0157] If temperature and viscosity are not entered, no correction will be made.

[0158] As an example of calculating each waveform value, calculations are performed to allocate each waveform value as follows: drive pulse_1 = boost value, drive pulse_2 = AL value, drive pulse_3 = 2*AL value, drive pulse_4 = 0.5*boost value - 0.4*AL value + 1.8, drive waveform cycle time = 5*AL value.

[0159] Finally, based on the type of head and its waveform value, the waveform is converted into digital register data according to its voltage pulse and each pulse time, and the setting value data is acquired and output.

[0160] (Procedure for using the drive waveform providing system) First, since the user does not have an actually measured AL value, they need to obtain setting value data for the drive waveform for AL measurement. To do this, the user accesses the drive waveform providing system 50, inputs the necessary parameters on the UI screen for parameter input processing shown in Figure 14, and selects the waveform for AL measurement in the waveform selection field, thereby requesting the provision of setting value data for the drive waveform for AL measurement. In response to the request, the drive waveform providing system 50 provides the setting value data for the drive waveform for AL measurement to the user.

[0161] FIG. 18 shows an example of a drive waveform for AL value. The drive waveform for AL measurement is a waveform pulse in which Draw and Release are repeated. The pulse time of Draw is 1 UL, and the pulse time of Release is 3 UL. Here, UL is an abbreviation for Unit Length, which is the smallest unit of pulse time. The drive waveform providing system 50 provides the user with setting value data for generating the drive waveform for AL measurement shown in FIG. 18.

[0162] The user performs an ink ejection evaluation using the provided setting value data of the drive waveform for AL measurement. The ink ejection evaluation is performed, for example, as follows: The drive voltage is fixed at a constant value, and the ink ejection speed is measured while the AL is varied. This obtains the relationship between the measured AL and the ejection speed. The measured AL value that provides the fastest ejection speed in the obtained relationship between the measured AL and the ejection speed is the optimal AL value.

[0163] Fig. 19 shows a graph illustrating an example of the relationship between the measured AL and the ejection speed. In the graph of measured AL vs. ejection speed shown in Fig. 19, the ejection speed is fastest when the measured AL value is 1.64 μs. Therefore, the measured AL value of 1.64 μs is the optimal AL value.

[0164] After obtaining the information on the optimum measured AL value, the user then accesses the drive waveform providing system 50, enters the necessary parameters on the UI screen for parameter input processing shown in Fig. 14, selects the optimum waveform in the waveform selection field, and enters the optimum measured AL value obtained in the discharge evaluation in the input field for the measured AL value, requesting provision of the optimum drive waveform setting value data. The drive waveform providing system 50 calculates the drive waveform setting value data using the measured AL value, and provides the user with the optimum drive waveform setting value data that meets their request.

[0165] When calculating waveform element values, the driving waveform providing system 50 uses equation (8): ink AL_value = AL_slope * test ink AL_value + AL_intercept. When a user requests setting value data for a driving waveform for AL measurement, the system uses an estimated AL value for the ink AL_value. When a user requests setting value data for an optimal driving waveform, the system uses an optimal measured AL value for the ink AL_value. This allows the driving waveform providing system 50 to provide setting value data for a driving waveform that meets the user's needs.

[0166] (effect) In the drive waveform providing system 50 according to the embodiment, a user can receive the setting value data of the drive waveform for AL measurement from the drive waveform providing system 50, use the data to determine the optimum actually measured AL value, and then pass the data to the drive waveform providing system 50, thereby receiving the setting value data of the optimum drive waveform. In other words, according to the embodiment, a drive waveform providing system 50 is provided that provides setting value data for generating an optimum drive waveform with minimal effort and time required by the user.

[0167] (others) The program executed by the driving waveform providing system according to the embodiment may be transferred in a state stored in an electronic device, or may be transferred in a state not stored in an electronic device. In the latter case, the program may be transferred via a network, or may be transferred in a state stored in a storage medium. The storage medium is a non-transitory tangible medium. The storage medium is a computer-readable medium. The storage medium may be in any form, such as a CD-ROM or a memory card, as long as it is capable of storing the program and is computer-readable.

[0168] Although the embodiments of the present invention have been described, they are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims. [Explanation of symbols]

[0169] 10...liquid ejection device, 11...control unit, 12...processor, 13...memory, 14...display, 15...operation unit, 16...communication interface, 21...conveyance motor, 22...motor drive circuit, 23...pump, 24...pump drive circuit, 25...inkjet head, 26...head controller, 27...system bus, 28...power supply circuit, 30...external terminal, 31...PC, 32...control server, 50...drive waveform providing system, 51...web server, 52...authentication server, 53...firewall, 54...application server, 55...web API server, 56...database server, 57...database, 60...computer, 61...processor, 62...ROM, 63...RAM , 64...auxiliary storage device, 65...input device, 66...output device, 67...communication device, 68...bus, 251...IC driver, 252...drive signal generation circuit, 253...drive waveform generation circuit, 254...analog switch circuit, 255...data processing circuit, 256...actuator group, 261...bus bridge, 262...setting value data buffer, 263...print data buffer, 264...control signal generation unit, 265...drive control unit, 266...setting value data transfer unit, 267...print data transfer unit, 268...control signal transfer unit, 2511...IC driver, 2521...analog switch circuit, 2551...data processing circuit, 2621...setting value data buffer, 2651...drive control unit, 2661...drive waveform generation circuit.

Claims

1. A driving waveform providing system for providing setting value data of a driving waveform of an inkjet head, a communication unit that communicates with an external terminal via a cloud; a response unit that generates response information in response to reception information received by the communication unit from the external terminal and provides the response information to the external terminal via the communication unit; and The response unit providing, to the external terminal, response information of an interface that accepts input of the inkjet head usage conditions, ink physical property values, and the type of the drive waveform in response to the received information requesting provision of the setting value data; If the type of the drive waveform is a drive waveform for AL measurement, the response information of the setting value data calculated based on the use conditions and the physical property values ​​is provided to the external terminal; If the type of the drive waveform is an optimum drive waveform, the response information of the setting value data calculated based on the use conditions, the physical property value, and the actually measured AL value is provided to the external terminal. Drive waveform providing system.

2. the response unit has a drive waveform estimation algorithm that uses the type of ink, the specific gravity of the ink, and the type of inkjet head as input variables; The driving waveform providing system according to claim 1 .

3. the interface accepts input of the type of the ink, the specific gravity of the ink, and the type of the inkjet head; The driving waveform providing system according to claim 2 .

4. the interface further receives input of the temperature of the ink, the viscosity of the ink, the serial number of the inkjet head, and a unique value of the inkjet head; The driving waveform providing system according to claim 3 .

5. the response unit corrects the setting value data based on the viscosity or temperature of the ink. The driving waveform providing system according to claim 1 .

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