Oscillation control circuit and inkjet head

Abstract

To provide an oscillation control circuit that can perform precursor control and printing control in a self-contained manner.SOLUTION: An oscillation control circuit comprises: a print data controller that receives and outputs print data; a precursor controller that generates and outputs precursor data; an interval controller that counts a resting time after printing or precursor driving is completed; and an adjustment controller that adjusts and controls the controllers. The print data controller notifies the adjustment controller of starting and completion of the printing. The precursor controller notifies the adjustment controller of the starting and completion of the precursor driving. After being notified of the completion of the printing or the precursor driving, the adjustment controller instructs the interval controller to start to count the resting time. The interval controller notifies the adjustment controller of completion of the counting, at a timing when the resting time reaches an interval set value. When being notified of completion of the counting, the adjustment controller instructs the precursor controller to output the precursor data.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to a swing control circuit and an inkjet head. [Background technology]

[0002] Generally, an inkjet head has a pressure chamber that contains ink, an actuator that expands and contracts the pressure chamber, and a head drive circuit that drives the actuator. The head drive circuit expands and contracts the pressure chamber with the actuator, thereby ejecting ink from a nozzle that communicates with the pressure chamber.

[0003] It is generally known that ink jet head drive control requires ink oscillation control (precursor control), which is a drive that prevents ink from being ejected at regular intervals even when the drive is paused, in order to prevent ink from sticking and maintain ejection performance.

[0004] Until now, for this precursor control, control has been performed in which precursor data is transferred from the print control device at a timing determined by the characteristics of the inkjet head, even though ink is not being ejected.

[0005] On the other hand, when printing is performed, precursor control is not necessary. Therefore, the print control device must manage the pause state and interval of the inkjet head, and adjust the print data and precursor data before transferring them. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-050492 Summary of the Invention [Problem to be solved by the invention]

[0007] Precursor control is undesirable for print control devices because it is a redundant control due to the unique characteristics of the inkjet head. Furthermore, it requires complex control resources and algorithms for coordination with print control and downtime management. This differs from traditional control and can lead to problems. Furthermore, the increased control resources are undesirable from a cost perspective.

[0008] For this reason, there is a demand for oscillation control that performs precursor control and printing control self-containedly on the inkjet head side.

[0009] The problem to be solved by the present invention is to provide a technique for performing precursor control and printing control self-containedly on the inkjet head side. [Means for solving the problem]

[0010] The oscillation control circuit according to the embodiment includes a print data controller that receives and outputs print data from an external device, a precursor controller that generates and outputs precursor data, an interval controller that counts the pause time from the end of printing or precursor drive, and an arbitration controller that arbitrates and controls the print data controller, precursor controller, and interval controller. The print data controller notifies the arbitration controller of the start and end of printing. The precursor controller notifies the arbitration controller of the start and end of precursor drive. Upon receiving notification of either the end of printing or the end of precursor drive, the arbitration controller instructs the interval controller to start counting the pause time. The interval controller notifies the arbitration controller of the end of counting when the pause time reaches the interval setting value. Upon receiving notification of the end of counting, the arbitration controller instructs the precursor controller to output precursor data.

[0011] The inkjet head according to the embodiment includes a pressure chamber that stores ink, a nozzle that communicates with the pressure chamber, an actuator that expands and contracts the pressure chamber to eject ink from the nozzle, a head drive circuit that drives the actuator, and the above-mentioned oscillation control circuit. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a block diagram showing an example of the configuration of a typical inkjet printer. [Figure 2] FIG. 2 is a block diagram showing an example of the configuration of a head and a print control device according to a conventional example. [Figure 3] FIG. 3 is a timing chart showing an outline of the operation in a configuration example of a head and a print control device according to a conventional example. [Figure 4] FIG. 4 is a block diagram showing an example of the configuration of a head and a print control device according to the embodiment. [Figure 5] FIG. 5 is a timing chart showing an outline of the operation in the example configuration of the head and print control device according to the embodiment. [Figure 6] FIG. 6 is a timing diagram of an example of an operation for executing printing during a pause time in an example of the configuration of a head and a print control device according to an embodiment. [Figure 7] FIG. 7 is a timing diagram of an example of an operation in which precursor driving is performed after a pause time has elapsed in an example of the configuration of a head and a print control device according to an embodiment. [Figure 8] FIG. 8 is a timing diagram of an example of an operation in which printing is performed simultaneously with the lapse of a pause time in an example configuration of a head and a print control device according to an embodiment. [Figure 9] FIG. 9 is a timing diagram of an example of an operation in which printing is performed while the precursor is being driven after the pause time has elapsed, in an example configuration of a head and a print control device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] (inkjet printer) First, an example of the configuration of a typical inkjet printer 200 will be described with reference to Fig. 1. Fig. 1 is a block diagram showing an example of the configuration of the inkjet printer 200. In addition to the inkjet printer 200, Fig. 1 also shows a print control device 300. In the following description, the inkjet printer 200 will be abbreviated as printer 200, and the inkjet head 100 will be abbreviated as head 100.

[0014] The printer 200 has a head 100. The head 100 has a head drive circuit 110 and an actuator group 120. The actuator group 120 has a plurality of actuators. Each actuator is a drive element that expands and contracts a pressure chamber that contains ink, causing ink droplets to be ejected from a nozzle that communicates with the pressure chamber. For example, each actuator is a piezoelectric drive element made of PZT (lead zirconate titanate). The head drive circuit 110 is a circuit that generates a drive signal for the actuator group 120. Each actuator of the actuator group 120 operates in accordance with the drive signal supplied from the head drive circuit 110 to expand and contract a pressure chamber, causing ink droplets to be ejected from a nozzle.

[0015] In addition to the head 100, the printer 200 has a processor 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, an operation panel 204, a communication interface 205, a conveying motor 206, a motor drive circuit 207, a pump 208, and a pump drive circuit 209. In the drawings, the interface is abbreviated as "IF."

[0016] The printer 200 also has bus lines 210 such as an address bus and a data bus. The processor 201, ROM 202, RAM 203, operation panel 204, communication interface 205, motor drive circuit 207, pump drive circuit 209, and head drive circuit 110 are connected to the bus line 210 directly or via input / output circuits, and can send and receive data to and from each other.

[0017] The processor 201 corresponds to the central part of the computer. The processor 201 controls each part to realize various functions of the printer 200 in accordance with an operating system and application programs. The processor 201 is, for example, a CPU (Central Processing Unit).

[0018] The ROM 202 corresponds to the read-only main memory of the computer. The ROM 202 stores the operating system and application programs. The ROM 202 may also store data necessary for the processor 201 to execute processes for controlling each unit.

[0019] The RAM 203 corresponds to the rewritable main memory of the computer. The RAM 203 stores data necessary for the processor 201 to execute processing. The RAM 203 is also used as a work area where information is rewritten as needed by the processor 201. The work area includes an image memory where print data is expanded.

[0020] The operation panel 204 has an operation section and a display section. The operation section has function keys such as a power key, a paper feed key, and an error reset key. The display section can display various statuses of the printer 200.

[0021] The communication interface 205 is an interface for communicating with external devices. The communication interface 205 is used, for example, for communication with the print control device 300, which transmits head drive data to the printer 200. The communication interface 205 also transmits a signal notifying the print control device 300 when an error occurs in the printer 200, for example. The communication interface 205 communicates with the print control device 300 via a wired or wireless network, for example, a LAN (Local Area Network). The print control device 300 is a control server or PC that controls the printer 200, etc.

[0022] A motor drive circuit 207 controls the driving of the transport motor 206. The transport motor 206 functions as a drive source for a transport mechanism that transports recording media such as printing paper. When the transport motor 206 starts, the transport mechanism begins transporting the recording media. The transport mechanism transports the recording media to a printing position using the head 100. After printing, the transport mechanism ejects the recording media from an ejection port (not shown) to the outside of the printer 200.

[0023] A pump drive circuit 209 controls the driving of the pump 208. When the pump 208 is driven, ink in an ink tank (not shown) is supplied to the head 100.

[0024] The head drive circuit 110 drives the actuator group 120 of the head 100 based on print data. The actuator group 120 expands and contracts pressure chambers that contain ink, causing ink droplets to be ejected from nozzles that communicate with the pressure chambers. In this way, the head 100 ejects ink onto a recording medium transported by a transport mechanism, and prints an image or the like on the recording medium.

[0025] (Head and print control device according to a conventional example) Next, a head 100 and a print control device 300 according to a conventional example will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of the configuration of a head 100 and a print control device 300 according to a conventional example.

[0026] The head 100 has a head drive circuit 110 and an actuator group 120. The head drive circuit 110 and the actuator group 120 have been described above. The head 100 has an interval setting value. The interval setting value is a setting value that specifies the time from the end of printing or the end of precursor drive to the start of the next precursor drive. The interval setting value is a value unique to the head 100. For example, the interval setting value differs depending on the type of head 100.

[0027] The print control device 300 outputs head drive data to the head drive circuit 110 of the head 100. The head drive data includes print data and precursor data. The print control device 300 outputs the print data to the head drive circuit 110 at any timing. The arbitrary timing is, for example, timing based on a print instruction input from the outside. The print control device 300 also outputs precursor data to the head drive circuit 110 at a predetermined timing. The predetermined timing is the timing when the downtime after the end of printing or precursor drive reaches the interval setting value. The print control device 300 outputs print data with priority over precursor data.

[0028] For this purpose, the print control device 300 includes a print data generator 301, a precursor data generator 302, an interval and arbitration controller 303, and a switch 304.

[0029] The interval and arbitration controller 303 arbitrates and controls the print data generator 301 , precursor data generator 302 , and switch 304 .

[0030] The print data generator 301 generates print data under the control of the interval and arbitration controller 303 , and outputs the generated print data to the switch 304 .

[0031] The precursor data generator 302 generates precursor data under the control of the interval & arbitration controller 303 , and outputs the generated precursor data to the switch 304 .

[0032] Under the control of the interval & arbitration controller 303, the switch 304 selects and outputs either the print data input from the print data generator 301 or the precursor data input from the precursor data generator 302 as head drive data.

[0033] The interval & arbitration controller 303 instructs the print data generator 301 to generate print data according to the externally input print content at a timing based on the externally input print instruction. In response to this, the print data generator 301 generates the print data.

[0034] The interval & arbitration controller 303 has a function of counting the downtime after printing or precursor driving ends. The interval & arbitration controller 303 instructs the precursor data generator 302 to generate precursor data when the downtime reaches the interval setting value. In response to this, the precursor data generator 302 generates precursor data.

[0035] The interval & arbitration controller 303 controls the switch 304 so that print data is output with priority over precursor data. That is, the switch 304 outputs nothing when there is no input, outputs print data when only print data is input, outputs precursor data when only precursor data is input, and outputs print data when print data and precursor data are input simultaneously.

[0036] The head drive circuit 110 of the head 100 includes a data controller 111 and a drive controller 112 .

[0037] The print control device 300 outputs head drive data to the data controller 111 of the head drive circuit 110 .

[0038] The data controller 111 recognizes the start byte of the input head drive data, separates the setting data from the print data, converts the data, manages the printing process, etc., generates the data necessary to generate the drive waveform, and outputs this to the drive controller 112.

[0039] Based on the data input from the data controller 111, the drive controller 112 generates drive waveforms for driving each actuator of the actuator group 120 and outputs these to the actuator group 120. The drive waveforms include a print waveform and a precursor waveform. The drive controller 112 outputs either the print waveform or the precursor waveform to the actuator group 120.

[0040] Each actuator of the actuator group 120 is driven in accordance with the input drive waveform, expanding and contracting a pressure chamber that contains ink, and ejecting ink from a nozzle that communicates with the pressure chamber.

[0041] Next, an overview of the operation of the head 100 and print control device 300 according to a conventional example will be described with reference to Fig. 3. Fig. 3 is a timing diagram showing an overview of the operation of an example configuration of the head 100 and print control device 300 according to a conventional example. Note that in some parts of the drawing, print data is abbreviated as "print" and precursor data as "pre."

[0042] In the pause times in Figure 3, FF represents the interval setting value, and xx represents a value smaller than FF. In the period Ta, the pause time has not reached the interval setting value. In contrast, in periods Tb, Tc, and Td, the pause time has reached the interval setting value. The timing diagram in Figure 3 shows the following:

[0043] During the period Ta, before the pause time reaches the interval setting value, the print control device 300 stops counting the pause time and outputs print data as head drive data to the head drive circuit 110 of the head 100. In response to this, the head drive circuit 110 outputs a print waveform as a drive waveform to the actuator group 120.

[0044] During period Tb, the pause time reaches the interval setting value. At that timing, the print control device 300 outputs precursor data as head drive data to the head drive circuit 110. In response to this, the head drive circuit 110 outputs a precursor waveform as a drive waveform to the actuator group 120.

[0045] During period Tc, the downtime reaches the interval setting value. At that timing, the print control device 300 outputs print data as head drive data to the head drive circuit 110. In response to this, the head drive circuit 110 outputs a print waveform as a drive waveform to the actuator group 120.

[0046] During period Td, the pause time reaches the interval setting value. At that timing, the print control device 300 outputs precursor data as head drive data to the head drive circuit 110. Thereafter, before the precursor drive ends, the print control device 300 outputs print data as head drive data to the head drive circuit 110. In response to this, the head drive circuit 110 first outputs a precursor waveform as a drive waveform to the actuator group 120, and then halfway through outputs a print waveform as a drive waveform to the actuator group 120.

[0047] In this conventional example configuration of the head 100 and print control device 300, the interval and arbitration controller 303 manages the downtime of the head 100 and outputs print data and precursor data as head drive data to the head drive circuit 110 of the head 100. The head drive data is transferred to the head drive circuit 110 as data that merges the print data and precursor data. The head drive circuit 110 that receives the head drive data cannot distinguish whether the head drive data is print data or precursor data. Therefore, if the print data and precursor data are not correctly selected and transferred, not only will the head not be able to demonstrate its inherent performance due to a control error, but there is also the risk of print quality problems such as mis-ejection or non-ejection occurring.

[0048] (Head and print control device according to an embodiment) Next, the head 100 and print control device 300 according to the embodiment will be described with reference to Fig. 4. Fig. 4 is a block diagram showing an example of the configuration of the head 100 and print control device 300 according to the embodiment.

[0049] The head 100 has a head drive circuit 110 and an actuator group 120. The head drive circuit 110 and the actuator group 120 have been described above. The head drive circuit 110 has a data controller 111 and a drive controller 112. The data controller 111 and the drive controller 112 have been described above. The head 100 has its own interval setting value. The interval setting value has been described above.

[0050] The head 100 performs precursor control and printing control in a self-contained manner. To this end, the head 100 has a swing control circuit 130. The swing control circuit 130 has a print data controller 131, a precursor controller 132, an interval controller 133, an arbitration controller 134, and a switch 135.

[0051] For example, the swing control circuit 130, or the swing control circuit 130 and the head drive circuit 110, can be configured by a programmable device such as an FPGA (Field-Programmable Gate Array).

[0052] For example, the print data controller 131, precursor controller 132, interval controller 133, and switch 135 operate asynchronously with each other. Of course, the print data controller 131, precursor controller 132, interval controller 133, and switch 135 may also operate synchronously with each other. The arbitration controller 134 arbitrates and controls the print data controller 131, precursor controller 132, interval controller 133, and switch 135.

[0053] The print control device 300 outputs head drive data to the oscillation control circuit 130 of the head 100. The head drive data is print data. For this reason, the print control device 300 has a print data generator 301. The print data generator 301 generates print data at any timing and outputs the generated print data to the print data controller 131 of the oscillation control circuit 130. The any timing is, for example, timing based on a print instruction input from outside.

[0054] The print data controller 131 receives print data from the print control device 300 under the control of the arbitration controller 134, and outputs the received print data to the switch 135. The print data controller 131 also notifies the arbitration controller 134 of the start and end of printing. The start and end of printing correspond to the start and end of output of print data, respectively. Although the timing of the start and end of printing does not strictly coincide with the timing of the start and end of output of print data, they are treated as synonymous here.

[0055] The precursor controller 132 generates precursor data under the control of the arbitration controller 134 and outputs the generated precursor data to the switch 135. The precursor controller 132 also notifies the arbitration controller 134 of the start and end of precursor driving. The start and end of precursor driving correspond to the start and end of precursor data output, respectively. Although the timing of the start and end of precursor driving and the timing of the start and end of precursor data output do not strictly coincide, they are treated as synonymous here.

[0056] Under the control of the arbitration controller 134, the interval controller 133 counts the downtime from the end of printing or precursor driving. Upon receiving notification of either the end of printing or the end of precursor driving, the arbitration controller 134 instructs the interval controller 133 to start counting the downtime. In response, the interval controller 133 starts counting the downtime. The interval controller 133 notifies the arbitration controller 134 of the end of counting when the downtime reaches the interval setting value. In response to the count end notification, the arbitration controller 134 instructs the precursor controller 132 to output precursor data. In response, the precursor controller 132 generates precursor data. The arbitration controller 134 also instructs the interval controller 133 to stop counting the downtime. In response, the interval controller 133 stops counting the downtime.

[0057] The print data controller 131 and precursor controller 132 operate based on the head clock. In contrast, the interval controller 133 operates based on an interval clock that has a lower frequency than the head clock. This is because it takes a relatively long time for the interval controller 133 to count the downtime, and the resolution of the downtime count can be coarse. This makes it possible to simplify the circuit configuration of the interval controller 133.

[0058] Under the control of the arbitration controller 134, the switch 135 selects either the print data input from the print data controller 131 or the precursor data output from the precursor controller 132 as head drive data, and outputs the selected head drive data to the data controller 111 of the head drive circuit 110.

[0059] The arbitration controller 134 controls the switch 135 so that the print data is output with priority over the precursor data. That is, the switch 135 outputs nothing when there is no input, outputs the print data when only the print data is input, outputs the precursor data when only the precursor data is input, and outputs the print data when the print data and precursor data are input simultaneously.

[0060] When the arbitration controller 134 receives a notification to start printing while counting the downtime, it instructs the switch 135 to output the print data. In response to this, the switch 135 outputs the print data. The arbitration controller 134 also instructs the interval controller 133 to stop counting the downtime. In response to this, the interval controller 133 stops counting the downtime.

[0061] When the arbitration controller 134 receives a notification of the start of printing while the precursor is being driven, it instructs the switch 135 to output print data. In response to this, the switch 135 stops outputting the precursor data and outputs the print data. Furthermore, if necessary, the arbitration controller 134 instructs the precursor controller 132 to stop outputting the precursor data. In response to this, the precursor controller 132 stops generating the precursor data.

[0062] Next, an overview of the operation of the head 100 and print control device 300 according to the embodiment will be described with reference to Fig. 5. Fig. 5 is a timing diagram showing an overview of the operation of an example configuration of the head 100 and print control device 300 according to the embodiment. Note that in some of the drawings, print data is abbreviated as "print" and precursor data as "pre."

[0063] The meaning of the pause time in Figure 5 is the same as in Figure 3. That is, in the pause time in Figure 5, FF means the interval setting value, and xx means a value smaller than FF. In the period Ta, the pause time has not reached the interval setting value. In contrast, in the periods Tb, Tc, and Td, the pause time has reached the interval setting value. The timing diagram in Figure 5 shows the following.

[0064] During period Ta, before the downtime reaches the interval setting value, print data, which is head drive data, is input from the print control device 300 to the swing control circuit 130 of the head 100. In response, the swing control circuit 130 stops counting the downtime and outputs the print data as head drive data to the head drive circuit 110. The head drive circuit 110 outputs a print waveform as a drive waveform to the actuator group 120.

[0065] During period Tb, the pause time reaches the interval setting value. At that timing, the oscillation control circuit 130 outputs precursor data as head drive data to the head drive circuit 110. The head drive circuit 110 outputs a precursor waveform as a drive waveform to the actuator group 120.

[0066] During period Tc, the pause time reaches the interval setting value. At that timing, precursor controller 132 outputs precursor data to switch 135. Also, print data, which is head drive data, is input from print control device 300 to print data controller 131 of oscillation control circuit 130. In response to this, print data controller 131 outputs the print data to switch 135. Also, interval controller 133 stops counting the pause time. Because switch 135 prioritizes print data over precursor data, it outputs the print data as head drive data to head drive circuit 110. Head drive circuit 110 outputs a print waveform as a drive waveform to actuator group 120.

[0067] During period Td, the pause time reaches the interval setting value. At that timing, the oscillation control circuit 130 outputs precursor data as head drive data to the head drive circuit 110. Thereafter, before precursor drive ends, print data, which is head drive data, is input to the oscillation control circuit 130 from the print control device 300. In response to this, the oscillation control circuit 130 stops counting the pause time and outputs print data as head drive data to the head drive circuit 110. The head drive circuit 110 initially outputs a precursor waveform as a drive waveform to the actuator group 120, and then halfway through outputs a print waveform as a drive waveform to the actuator group 120.

[0068] In this configuration example of the head 100 and print control device 300 according to the embodiment, unlike the configuration example of the head 100 and print control device 300 according to the conventional example, management of the head 100's downtime and precursor control are self-contained on the head 100 side. Also, because the only head drive data input to the head 100 is print data, there is very little risk of control errors occurring, and the head's inherent performance can easily be demonstrated. Furthermore, because the print control device 300 basically only needs to have the print data generator 301, the head 100 according to the embodiment can be connected to a wide variety of print control devices 300 without having to choose a specific print control device 300.

[0069] Next, an example of operation in which printing is performed during a pause time in the head 100 and print control device 300 according to the embodiment will be described with reference to Fig. 6. Fig. 6 is a timing diagram of an example of operation in which printing is performed during a pause time in the example configuration of the head 100 and print control device 300 according to the embodiment. The timing diagram in Fig. 6 shows the following.

[0070] During period Ta, at the last clock of the pause time clock (pause time count = xx < FF), the swing control circuit 130 outputs the print data L1 as head drive data to the head drive circuit 110. Also, at the timing when period Ta ends, the swing control circuit 130 stops counting the pause time. After that, the swing control circuit 130 outputs the print data L2 and the dummy print data as head drive data to the head drive circuit 110.

[0071] The head drive circuit 110 outputs the print waveform of the print data L1 as the drive waveform to the actuator group 120. The head drive circuit 110 starts outputting the print waveform of the print data L1 at the timing of the start of the input of the print data L2. The head drive circuit 110 continues to output the print waveform of the print data L1 for a period equal to the time interval between the start of the input of the print data L1 and the start of the input of the print data L2.

[0072] Next, the head drive circuit 110 starts outputting the print waveform of the print data L2 at the timing of the start of the input of the dummy print data. The head drive circuit 110 continues to output the print waveform of the print data L2 for a period equal to the time interval between the start of the input of the print data L2 and the start of the input of the dummy print data. After that, the interval controller 133 starts counting the pause time again. Note that the head drive circuit 110 does not output a print waveform for the dummy print data.

[0073] Next, while referring to FIG. 7, an operation example of performing a precursor drive after the pause time in the head 100 and the print control device 300 according to the embodiment will be described. FIG. 7 is a timing diagram in an operation example of performing a precursor drive after the pause time in a configuration example of the head and the print control device according to the embodiment. The timing diagram of FIG. 7 shows the following.

[0074] During period Tb, the pause time reaches the interval setting value at the last clock of the pause time clock (pause time count = FF). At that timing, the oscillation control circuit 130 outputs precursor data P1 to the head drive circuit 110 as head drive data. The oscillation control circuit 130 also finishes counting the pause time. Thereafter, the oscillation control circuit 130 outputs precursor data P2 and dummy precursor data to the head drive circuit 110 as head drive data.

[0075] The head drive circuit 110 outputs the precursor waveform of precursor data P1 as a drive waveform to the actuator group 120. The head drive circuit 110 starts outputting the precursor waveform of precursor data P1 at the timing when input of precursor data P2 starts. The head drive circuit 110 continues outputting the precursor waveform of precursor data P1 for a period equal to the time interval between the start of input of precursor data P1 and the start of input of precursor data P2.

[0076] Next, the head drive circuit 110 starts outputting the precursor waveform of precursor data P2 at the timing when the input of the dummy precursor data starts. The head drive circuit 110 continues outputting the precursor waveform of precursor data P2 for a period equal to the time interval between the start of input of precursor data P2 and the start of input of the dummy precursor data. Thereafter, the interval controller 133 starts counting the pause time again at the timing when the output of the precursor waveform of precursor data P2 ends. Note that the head drive circuit 110 does not output a precursor waveform for the dummy precursor data.

[0077] Next, an example of operation in which printing is performed simultaneously with the lapse of a pause time in the head 100 and print control device 300 according to the embodiment will be described with reference to Fig. 8. Fig. 8 is a timing diagram of an example of operation in which printing is performed simultaneously with the lapse of a pause time in the example configuration of the head and print control device according to the embodiment. The timing diagram in Fig. 8 shows the following.

[0078] During period Tc, the pause time reaches the interval setting value at the last clock of the pause time clock (pause time count = FF). At that timing, precursor controller 132 outputs precursor data P1 to switch 135. Also, print data controller 131 outputs print data L1 to switch 135. Also, interval controller 133 stops counting the pause time. Because switch 135 prioritizes print data L1 over precursor data P1, it outputs print data L1 to head drive circuit 110 as head drive data.

[0079] Thereafter, the precursor controller 132 outputs precursor data P2 and dummy precursor data to the switch 135. In addition, the print data controller 131 outputs print data L2 and dummy print data to the switch 135. The switch 135 outputs the print data L2 and dummy print data to the head drive circuit 110 as head drive data.

[0080] The head drive circuit 110 outputs the print waveform of the print data L1 as a drive waveform to the actuator group 120. The head drive circuit 110 starts outputting the print waveform of the print data L1 at the timing when the input of the print data L2 starts. The head drive circuit 110 continues outputting the print waveform of the print data L1 for a period equal to the time interval between the start of the input of the print data L1 and the start of the input of the print data L2.

[0081] Next, the head drive circuit 110 starts outputting the print waveform of print data L2 at the timing when the input of the dummy print data begins. The head drive circuit 110 continues outputting the print waveform of print data L2 for a period equal to the time interval between the start of input of print data L2 and the start of input of the dummy print data. Thereafter, the interval controller 133 starts counting the pause time again at the timing when the output of the print waveform of print data L2 ends. Note that the head drive circuit 110 does not output a print waveform for the dummy print data.

[0082] Next, an example of operation in which printing is performed while the precursor is driven after the pause time has elapsed in the head 100 and print control device 300 according to the embodiment will be described with reference to Figure 9. Figure 9 is a timing diagram of an example of operation in which printing is performed while the precursor is driven after the pause time has elapsed in the example configuration of the head and print control device according to the embodiment. The timing diagram in Figure 9 shows the following.

[0083] During period Tc, the pause time reaches the interval setting value at the last clock of the pause time clock (pause time count = FF). At that timing, precursor controller 132 outputs precursor data P1 to switch 135. Also, print data controller 131 outputs print data L1 to switch 135. Also, interval controller 133 stops counting the pause time. Switch 135 outputs print data L1 to head drive circuit 110 as head drive data.

[0084] Thereafter, the precursor controller 132 outputs the precursor data P2 and the dummy precursor data to the switch 135. The head drive circuit 110 outputs the precursor waveform of the precursor data P1 as a drive waveform to the actuator group 120. The head drive circuit 110 starts outputting the precursor waveform of the precursor data P1 at the timing when the input of the precursor data P2 starts. The head drive circuit 110 continues outputting the precursor waveform of the precursor data P1 for a period equal to the time interval between the start of the input of the precursor data P1 and the start of the input of the precursor data P2.

[0085] While the precursor controller 132 is outputting precursor data P2, the print data controller 131 outputs print data L1 to the switch 135. Because the switch 135 prioritizes print data L1 over precursor data P2, after the print data L1 is input, while the precursor data P2 is being output, the print data controller 131 outputs print data L2 and dummy print data to the switch 135. The switch 135 outputs the print data L2 and dummy print data to the head drive circuit 110 as head drive data.

[0086] The head drive circuit 110 outputs the print waveform of the print data L1 as a drive waveform to the actuator group 120. Note that the head drive circuit 110 does not output the precursor waveform of the partially input precursor data P2 as a drive waveform. The head drive circuit 110 starts outputting the print waveform of the print data L1 at the timing when the input of the print data L2 starts. The head drive circuit 110 continues outputting the print waveform of the print data L1 for a period equal to the time interval between the start of the input of the print data L1 and the start of the input of the print data L2.

[0087] Next, the head drive circuit 110 starts outputting the print waveform of print data L2 at the timing when the dummy print data starts to be input. The head drive circuit 110 continues outputting the print waveform of print data L2 for a period equal to the time interval between the start of input of print data L2 and the start of input of the dummy print data. After that, the interval controller 133 starts counting the pause time again. Note that the head drive circuit 110 does not output a print waveform for the dummy print data.

[0088] (effect) According to the embodiment, the print control device 300 does not need to transfer or control precursor data for oscillation control, which is determined by the characteristics of the head 100. As a result, the print control device 300 can transfer print data and perform printing at the timing originally required. As a result, the print control device 300 does not need to perform oscillation control for the head 100, and the print control device 300 has a general configuration, which greatly simplifies the configuration. Furthermore, the head 100 can self-contain oscillation control, which is determined by the characteristics of the head 100. As a result, the head 100 can be connected without having to select a print control device 300.

[0089] That is, according to the embodiment, a technique is provided in which precursor control and printing control are performed self-containedly on the head 100 side.

[0090] Although several embodiments of the present invention have been described, these embodiments 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 scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0091] 100...inkjet head or head, 110...head drive circuit, 111...data controller, 112...drive controller, 120...actuator group, 130...oscillation control circuit, 131...print data controller, 132...precursor controller, 133...interval controller, 134...arbitration controller, 135...switcher, 200...inkjet printer or printer, 201...processor, 202...ROM, 203...RAM, 204...operation panel, 205...communication interface, 206...conveyor motor, 207...motor drive circuit, 208...pump, 209...pump drive circuit, 210...bus line, 300...print control device, 301...print data generator, 302...precursor data generator, 303...arbitration controller, 304...switcher.

Claims

1. An oscillation control circuit for an inkjet head, a print data controller that receives and outputs print data from an external device; a precursor controller that generates and outputs precursor data; an interval controller for counting the rest time from the end of printing or precursor driving; an arbitration controller that arbitrates and controls the print data controller, the precursor controller, and the interval controller; The print data controller notifies the arbitration controller of the start and end of printing; The precursor controller notifies the arbitration controller of the start and end of precursor driving; the arbitration controller receives a notification of either the end of printing or the end of precursor driving and instructs the interval controller to start counting a pause time; the interval controller notifies the arbitration controller of the end of counting when the pause time reaches the interval setting value; Upon receiving notification of the end of counting, the arbitration controller instructs the precursor controller to output precursor data. Oscillation control circuit.

2. a switch for selecting and outputting either the print data input from the print data controller or the precursor data input from the precursor controller as head drive data; the arbitration controller controls the switch so as to output the print data with priority over the precursor data; 2. The oscillation control circuit according to claim 1.

3. When the arbitration controller receives a notification of the start of printing while counting the pause time, instructing the interval controller to stop counting the downtime; instructing the switch to output print data; 3. The oscillation control circuit according to claim 2.

4. When the arbitration controller receives a notification of the start of printing while the precursor is being driven, instructing the switch to output print data; 3. The oscillation control circuit according to claim 2.

5. a pressure chamber that contains ink; a nozzle communicating with the pressure chamber; an actuator that expands and contracts the pressure chamber to eject ink from the nozzle; a head drive circuit that drives the actuator; and a swing control circuit according to any one of claims 1 to 4. Inkjet head.

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