JP2011020332A - Fluid injection device, fluid injection head control method in the fluid injection device, and driving waveform generator for fluid injection head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid injection device, a fluid injection head control method and a driving waveform generator, capable of indicating generation timing of a driving waveform to a fluid injection head, without transmitting a timing signal through a timing signal line, from an injection indication part to a waveform generation part. <P>SOLUTION: A control system for a plurality of recording heads 17 includes the N-number of data control substrates 20 (superordinate substrate), and the N×M number of head module substrates 21 (subordinate substrate). A data transfer module 69 in a data control substrate 20 side transfers a data DATA in which a waveform kind data WD (header) generated by a waveform kind data generating part 67 is added to a delivery data SI read out from a buffer 68, at a period synchronized with the timing signal TS generated based on an encoder pulse signal ES by a PLL 66. A driving waveform signal generating circuit 73 in a head module 21 side transmits a driving waveform signal COM to the recording heads 17, at a period synchronized with reception timing of the data DATA. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fluid ejecting apparatus including a fluid ejecting head that ejects a fluid such as ink, such as an ink jet printer, a fluid ejecting head control method in the fluid ejecting apparatus, and a drive waveform generating device for the fluid ejecting head.

  2. Description of the Related Art Conventionally, an ink jet printer including a recording head that ejects ink is known as one of fluid ejecting apparatuses that eject fluid (for example, Patent Document 1). In the printer described in Patent Document 1, ink droplets are ejected by applying a voltage having a predetermined drive waveform to a piezoelectric vibrator provided for each nozzle in the recording head. A drive waveform signal (trapezoidal wave signal) that controls the waveform of the voltage applied to the piezoelectric vibrator is generated and recorded by a drive signal generation circuit (waveform generation unit) provided in the control circuit that controls the recording head. Transmit to the head drive circuit in the head. At this time, ejection data (ejection information) instructing the presence or absence of ejection for each nozzle is sent from the control circuit to the head drive circuit. At this time, the head drive circuit responds to the piezoelectric vibrator corresponding to the nozzle whose ejection data is “0”. By applying a voltage to the piezoelectric vibrator corresponding to the nozzle whose ejection data is “1” without applying a voltage to the nozzle, a nozzle for ejecting ink droplets is selected based on the ejection data.

  Further, a pulse signal (encoder pulse signal) from an encoder that detects a relative position between the recording head and the recording medium (target) is input to the control circuit. A drive waveform signal generation circuit in the control circuit transmits (outputs) a drive waveform signal for each period proportional to the pulse period based on the encoder pulse signal. The control circuit transmits a printing timing signal generated based on the encoder pulse signal to the recording head, and the recording head is controlled to be ejected based on the drive waveform signal and the ejection data at a timing synchronized with the printing timing signal. In addition, although the printer of patent document 1 was provided with one recording head, the serial printer (for example, patent document 2 etc.) provided with several recording head, the line printer (for example, patent document 3), etc. are disclosed. ing.

Japanese Patent Laid-Open No. 2003-1824 JP 2003-118136 A JP 2007-69448 A

  By the way, when a printer having a plurality of recording heads is configured as in Patent Documents 2 and 3 using the recording head and control circuit described in Patent Document 1, a plurality of recording heads and a plurality of control boards are provided. There is a need. In this case, if the control circuit is divided into an upper board having an injection instruction section that mainly gives instructions necessary for control and a lower board that controls the recording head as instructed, for example, the user maker needs the upper board to meet the needs. In addition to being able to set the corresponding instruction content, it is possible to provide the lower substrate and recording head as a general-purpose product common to all user manufacturers. In particular, when a plurality (M) of lower substrates are connected to one upper substrate, the total number of substrates can be reduced, the configuration of the printhead unit and its assembly work can be simplified, and the upper substrate can be connected. It is also possible to suppress the number of lower substrates to a required number less than M.

  Further, the control circuit may be provided with a waveform designation signal transmission unit that transmits a waveform designation signal that designates the waveform of the drive waveform signal, but the waveform designation signal transmission unit that designates the waveform belongs to the injection instruction unit. It is preferable to provide the upper substrate. In addition, it is desirable to provide a waveform generation unit including a drive signal generation circuit that performs a prescribed process for generating a drive waveform signal having a waveform specified by the waveform specification signal on a lower substrate.

  In this case, it is necessary to transmit the pulse period information of the encoder to the drive waveform signal generation circuit of the lower substrate. For example, a configuration is possible in which signal lines from an encoder are individually wired on a plurality (M) of lower substrates. However, since M signal lines are required, an increase in the number of wires is inevitable. Therefore, a configuration is conceivable in which a signal line from the encoder is connected to the upper substrate, and a timing signal having a pulse period that is the same as or proportional to the encoder pulse signal is transmitted from the upper substrate to a plurality of lower substrates. However, this configuration also requires timing signal lines for transmitting M timing signals between the upper board and a plurality (M) of lower boards, and the wiring structure is increased due to the increase in the number of wirings. Complexity and complicated assembly work are inevitable. Because of such problems, the drive waveform signal to the recording head can be transmitted from the injection instruction unit on the upper substrate to the waveform generation unit on the lower substrate without transmitting a timing signal based on the encoder pulse signal through the timing signal line. Realization of a configuration capable of instructing the supply timing of (drive waveform) is desired.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to generate a drive waveform for a fluid ejecting head without transmitting a timing signal from the ejection instruction unit to the waveform generating unit through a timing signal line. It is an object to provide a fluid ejecting apparatus capable of instructing supply timing, a fluid ejecting head control method in the fluid ejecting apparatus, and a drive waveform generating device for the fluid ejecting head.

  In order to solve the above-described problems, the present invention is a fluid ejecting apparatus that receives fluid waveform information relating to a fluid ejecting head that ejects fluid and a drive waveform that drives the fluid ejecting head, and ejects the fluid ejecting head. Based on an ejection instruction unit that performs an instruction regarding timing and a waveform instruction that instructs a driving waveform through a common signal line, and an instruction regarding an ejection timing of the fluid ejection head received through the common signal line and a waveform instruction that instructs a driving waveform And a waveform generation unit that generates a drive waveform and supplies the drive waveform to the fluid ejection head at an instructed timing.

  According to the present invention, the ejection instructing unit receives waveform information relating to the driving waveform for driving the fluid ejecting head, and performs an instruction relating to the ejection timing of the fluid ejecting head and a waveform instruction instructing the driving waveform through a common signal line. . The waveform generation unit generates a drive waveform based on the instruction regarding the ejection timing of the fluid ejection head received through the common signal line and the waveform instruction that instructs the drive waveform, and supplies the drive waveform to the fluid ejection head at the instructed timing. . Therefore, the ejection timing of the fluid ejection head can be instructed without providing a dedicated timing signal line for transmitting the timing signal from the ejection instruction unit to the waveform generation unit. For example, wiring such as a signal line dedicated for timing signal transmission is not necessary, and the number of necessary wirings can be reduced.

In the fluid ejecting apparatus according to the aspect of the invention, it is preferable that the timing at which the data including the waveform instruction is transmitted is an instruction of the ejection timing of the fluid ejecting head.
According to the present invention, since the timing for transmitting data including the waveform instruction is an instruction for the ejection timing of the fluid ejection head, there is no need to transmit a timing signal.

  The fluid ejecting apparatus of the present invention includes a plurality of the waveform generation units, and the ejection instruction unit individually instructs each of the plurality of waveform generation units regarding an ejection timing of the fluid ejection head and a waveform instruction for instructing a drive waveform. It is preferable to carry out.

According to the present invention, the number of waveform generation units connected to the injection instructing unit can be selected according to the required number, so that the waveform generation unit is less likely to be wasted.
The present invention is a fluid ejecting head control method in a fluid ejecting apparatus including a fluid ejecting head that ejects a fluid, wherein the ejection instructing unit receives waveform information relating to a drive waveform for driving the fluid ejecting head, and fluid ejecting A step of performing a command regarding the ejection timing of the head and a waveform command for instructing a driving waveform through a common signal line, and a waveform generation unit instructing an instruction and a driving waveform regarding the ejection timing of the fluid ejection head received through the common signal line And a step of generating a drive waveform based on the waveform instruction to be supplied to the fluid ejecting head at the instructed timing. According to this invention, the same effect as the invention of the fluid ejecting apparatus can be obtained.

  The present invention relates to a drive waveform generation device for a fluid ejection head having a waveform generation unit that generates a drive waveform for driving the fluid ejection head and supplies the generated fluid waveform to the fluid ejection head, and the drive waveform for driving the fluid ejection head The waveform generation unit receives the waveform information about the ejection timing of the fluid ejection head and the waveform instruction for instructing the drive waveform through a common signal line. The gist is to generate a drive waveform based on an instruction related to the ejection timing of the fluid ejecting head and a waveform instruction to instruct a drive waveform, and supply the drive waveform to the fluid ejecting head at the instructed timing. According to the present invention, when the drive waveform generation device and the ejection instruction device are configured in combination, a signal line for a timing signal is not required between the both devices, so that the wiring can be reduced. The same effect as the invention can be obtained.

1 is an electrical configuration block diagram of an ink jet printer according to an embodiment. The perspective view which shows the printer of a serial recording system. FIG. 2 is a schematic plan view showing a line recording type printer. FIG. 3 is a block diagram illustrating an electrical configuration of a recording head unit. Table data. FIG. 3 is a block diagram illustrating a detailed electrical configuration of a main part of the recording head unit. The timing chart which concerns on data transmission. The timing chart of the modification which transmits a drive waveform signal with the reception timing of waveform seed data. The timing chart of the modification different from FIG. 8 which transmits a drive waveform signal with the reception timing of waveform seed data.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. FIG. 1 is an electrical configuration block diagram of an ink jet printer as a fluid ejecting apparatus.
As shown in FIG. 1, an ink jet printer (hereinafter simply referred to as “printer 11”) is communicably connected to the host apparatus 100 and performs printing based on print data PD received from the host apparatus 100. The host device 100 is composed of a personal computer, for example, and includes a main body 101, a monitor 102, and an input device 103. A printer driver 105 is built in the main body 101. The printer driver 105 is a print that can be interpreted by the printer 11 from data (image data or document data) displayed on the monitor 102 when, for example, the user instructs execution of printing by operating the input device 103. Data PD is generated and transmitted to the printer 11.

  Specifically, the printer driver 105 performs resolution conversion processing, color conversion processing, halftone processing, rasterization processing, and the like on image data to be printed, for example, so that one dot has a plurality of gradations (two gradations in this example). Expressed print data (raster data) is generated. The printer driver 105 includes, in the print data, print condition information including paper size, paper type, and print speed mode designation information, and commands for instructing various print operations such as paper feed, print, and paper feed. Print data PD is generated with a header.

  The printer 11 includes a communication interface (hereinafter referred to as “communication I / F 12”), and receives print data PD from the host device 100 via the communication I / F 12. The print data PD received via the communication I / F 12 is temporarily stored in the buffer 13. The control unit 14 interprets a command in the print data PD read from the buffer 13 and causes the printer 11 to perform a printing operation instructed by the command. Further, the control unit 14 sends the print data (raster data) in the print data PD to the distributor 15 (distributor). In the printer 11, only print data for a plurality of lines (for a plurality of lines) can be stored due to the limitation of the data storage area. Therefore, communication is performed between the host apparatus 100 and the printer 11, and the print data PD is transferred line by line every time printing for one line is completed on the printer 11 side and the storage area is vacant.

  As shown in FIG. 1, the printer 11 includes a recording unit 16 for ejecting ink onto a recording medium (for example, paper) as a target. The recording unit 16 of this embodiment is configured by arranging a plurality of recording heads 17 in a predetermined arrangement pattern (however, in FIG. 1, the arrangement pattern is not expressed and is schematically drawn in an arrangement of one row. ing).

  Between the distributor 15 and each recording head 17, as a control system circuit (electronic circuit) for performing ejection control of each recording head 17 based on print data, a data control board 20 as an ejection instruction unit, and a drive waveform A generation module and a head module substrate 21 as a waveform generation unit are provided. Each board 20, 21 is provided with a plurality of connectors (not shown), and up to “M” head module boards 21 can be connected to one data control board 20, and one head module Up to “K” recording heads 17 can be connected to the substrate 21. FIG. 1 shows an example in which the number N of data control boards 20 is “2”, the number M of head module boards 21 is “4”, and the number K of recording heads 17 is “1”. Of course, these N, M, and K can be changed as appropriate. For example, K may be plural (K ≧ 2). When K is plural, the number of head module substrates 21 can be suppressed to the number of recording heads, and the number of parts of the recording head unit can be reduced, so that the assembling work can be simplified. However, it is preferable that M is plural (M ≧ 2). This is because the number of head module substrates 21 connected to the data control substrate 20 can be increased or decreased according to the required number of recording heads 17, and the waste of circuits can be eliminated by reducing the number of head module substrates 21 to the minimum required number. Because.

  By using one distributor 15, N data control boards 20, N × M head module boards 21, and (N × M × K) recording heads 17, the recording head unit can be used for a serial printer. It can also be configured for line printers. The head module substrate 21 and the recording head 17 are connected via a flexible flat cable.

  As shown in FIG. 1, the printer 11 includes an electric motor 24 that is a power source of a moving unit that relatively moves the recording head 17 and the recording medium (paper or the like), and a relative relationship between the recording head 17 and the recording medium. An encoder 25 used for measuring the relative position in the movement direction is provided. The encoder 25 outputs an encoder pulse signal ES including pulses having a pulse number proportional to the relative movement distance between the recording head 17 and the recording medium and a pulse period inversely proportional to the relative movement speed.

  In this embodiment, the control system electronic circuit (control circuit) for driving and controlling the recording head 17 is set to reflect the needs of each user manufacturer (recording method such as serial type / line type and design concept). A relatively flexible data control board 20 that can be set, and a relatively versatile head module board 21 that can perform setting processing according to instructions from the upstream side (that is, the data control board 20) although it cannot be changed. It is divided into. For example, a user manufacturer can construct a desired recording head unit relatively easily by using the recording head 17 and the head module substrate 21 and combining them with the data control substrate 20 having a desired setting. Is mounted on the housing unit, the printer 11 (fluid ejecting apparatus) having a desired function can be manufactured relatively easily.

  Further, since the electronic circuit of the head control system is divided into the two types of boards 20 and 21, there is a concern that the wiring for connecting the control unit 14 and the encoder 25 and the boards 20 and 21 may increase. In the embodiment, the number of wirings can be made relatively small relative to the number of the recording heads 17 by the configuration described later. A specific configuration for each recording method of the printer 11 equipped with the recording head unit of this embodiment will be described later.

  The data controller 22 shown in FIG. 1 inputs the ejection data DI for four heads from the distributor 15, the encoder pulse signal ES from the encoder 25, and the waveform type parameter WP from the control unit 14. Then, the data controller 22 adds the waveform type parameter WP to the ejection data SI for one nozzle row, which is the amount of ink droplets to be ejected simultaneously, out of the ejection data DI, and is proportional to the pulse period of the encoder pulse signal ES. The data is sequentially transferred to the head controller 23 every printing cycle.

  The head controller 23 generates a drive waveform signal COM having a waveform indicated by the waveform type parameter WP, and generates the generated drive waveform signal COM and the ejection data SI in the recording head 17 at a timing for each print cycle. Is transmitted to the head driving circuit 26. In the present embodiment, the data controller 22 transfers data to the head controller 23 every cycle proportional to the pulse cycle of the encoder pulse signal ES, while the head controller 23 synchronizes with the data reception timing from the data controller 22. It is characterized in that the transmission timing of the drive waveform signal COM and the generation of the print timing signal are performed. This characteristic configuration makes it unnecessary to connect the signal line of the encoder 25 to each head controller 23. The detailed configuration and detailed processing contents of the data control board 20 and the head module board 21 will be described later.

  Next, the configuration of each of the serial printer and the line printer to which the recording head unit is applied will be briefly described. The plurality of recording heads 17 are arranged in a predetermined arrangement pattern according to the recording method of the printer to which the recording head unit is applied.

  First, the configuration of the serial printer will be described with reference to FIG. FIG. 2 is a schematic perspective view of the serial printer. When the printer 11 is the serial printer 11A shown in FIG. 2, the carriage 31 on which the recording unit 16 is mounted is moved in the main scanning direction (the X direction in FIG. 2) along the guide shaft 33 installed in the main body case 32. It is provided in a state where it can be reciprocated by being guided by. The carriage 31 is fixed to an endless timing belt 36 wound around a pair of pulleys 34, 35 disposed on the inner surface of the back plate of the main body case 32, and a carriage having a drive shaft connected to one pulley 34. The carriage 31 is configured to reciprocate in the main scanning direction X by driving the motor 37 forward and backward.

  As shown in FIG. 2, a platen 38 that defines the interval between the recording unit 16 and the recording medium P (paper) is disposed in a lower position facing the recording unit 16 in the main body case 32 so as to extend in the X direction. Has been. Further, the ink supplied from the black and color ink cartridges 39 and 40 detachably loaded on the upper portion of the carriage 31 is classified by ink color of the recording head 17 (see FIG. 1) constituting the recording unit 16. The nozzle is ejected (discharged).

  An automatic sheet feeder 41 (Auto Sheet Feeder) installed on the back side of the printer 11 supplies a large number of recording media P stacked on the sheet feed tray 42 to the downstream side in the sub-scanning direction Y one by one. . Further, by driving the paper feed motor 43 disposed at the lower right side of the main body case 32 in FIG. 2, a pair of paper feed rollers and a pair of paper discharge rollers (not shown) are driven to rotate, and after feeding The recording medium P is intermittently conveyed in the sub-scanning direction Y. Then, a printing operation for ejecting ink from the nozzles of the recording heads 17 constituting the recording unit 16 toward the recording medium P while reciprocating the carriage 31 in the main scanning direction X, and the recording medium P in the sub-scanning direction Y are performed. By repeating the paper feeding operation of intermittently carrying a predetermined carry amount approximately alternately, characters, images, and the like based on the print data PD are printed on the recording medium P.

  In the serial printer 11 </ b> A, the encoder 25 is composed of a linear encoder that extends along the guide shaft 33. The encoder 25 includes a linear scale composed of a tape-shaped code plate in which a plurality of slits are perforated at regular intervals, and a pair of sensors having a light emitting / receiving function, and a moving distance of the carriage 31 (recording head unit 16). An encoder pulse signal ES having a number of pulses proportional to is output. The control unit 14 (see FIG. 1) drives and controls the carriage motor 37 based on the movement position, movement direction, and movement speed of the carriage 31 obtained using the encoder pulse signal ES input from the encoder 25. The speed control and position control of the carriage 31 are performed. A maintenance device 44 that performs cleaning or the like for preventing or eliminating nozzle clogging of the recording unit 16 is disposed immediately below the carriage 31 when it is positioned at the home position. The maintenance device 44 has a cap 45 for capping the recording unit 16 in the home position. During printing, the carriage 31 periodically moves to the home position, and flushing is performed toward the cap 45 to eject ink droplets from all the nozzles of the recording unit 16. The recording unit 16 is connected to the head module substrate 21 (see FIG. 1) via a flexible flat cable (hereinafter referred to as “FFC 46”).

  In the case of the serial printer 11A, since the head module substrate has conventionally been configured to include the data controller function, it is necessary to connect a total of (N × M) signal lines from the encoder to each head module substrate. . On the other hand, in the present embodiment, only N signal lines from the encoder 25 are connected to the N data control boards 20. For this reason, the number of signal lines of the encoder 25 required in the conventional configuration (N × M) (eight as an example) is N in the configuration of this example (two as an example). In this configuration, the number of "1 / M" necessary for the number is sufficient.

  Next, the line printer will be described. FIG. 3 is a schematic plan view of the line printer. As shown in FIG. 3, when the printer 11 is a line printer 11 </ b> B, the recording medium P is fed by a roller 55 onto a conveyance belt 54 wound around a plurality of rollers 51 to 53. The recording unit 16 is disposed at a position with a predetermined gap from the belt surface to the upper side (the front side in the direction orthogonal to the paper surface in FIG. 3) at the approximate center of the conveyance belt 54 in the conveyance direction. The recording unit 16 is a so-called multi-head type recording unit in which a plurality of recording heads 17 (see FIG. 4) are arranged in a predetermined arrangement (for example, a staggered arrangement) that allows recording over the entire width of the maximum recording medium. .

  The conveyance motor 56 shown in FIG. 3 corresponds to the electric motor 24 in FIG. 1, and the control unit 14 (see FIG. 1) drives the conveyance motor 56 so that the conveyance belt 54 is in the conveyance direction Y (left side in FIG. 3). Thus, the recording medium P on the transport belt 54 is transported in the transport direction Y at a constant speed. Printing is performed on the recording medium P by ejecting ink droplets from the recording heads 17 (see FIG. 1) of the recording unit 16 onto the recording medium P being conveyed at a constant speed. As shown in FIG. 3, an encoder 25 made of a linear encoder is provided over the entire circumference of the conveyor belt 54 on one side edge on the surface of the conveyor belt 54. The encoder 25 has a linear scale 25A and a sensor 25B having a light emitting / receiving function. Signal lines are respectively connected between the sensor 25B of the encoder 25 and the N data control boards 20 (see FIG. 1). For this reason, in the line printer 11 </ b> B, only N signal lines from the encoder 25 are connected to the N data control boards 20.

  FIG. 4 is a schematic diagram showing the bottom surface of the control circuit and the recording unit. FIG. 4 shows a simple example in which the number of connected head module substrates per data control substrate is two. As shown in FIG. 4, a plurality of (for example, four) recording heads 17 constituting the recording unit 16 are arranged in a staggered manner. For each ink color (K, C, M, Y) in which J (180 nozzles) nozzles (nozzle openings) are arranged at regular nozzle pitch intervals on the nozzle opening surface (bottom surface) of the recording head 17. Nozzle rows 17K, 17C, 17M, and 17Y are provided. By arranging a plurality of recording heads 17 in a staggered arrangement, nozzle rows of the same color are positioned so as to be continuously distributed in the nozzle row direction (vertical direction in FIG. 4) between the diagonally adjacent recording heads 17.

  The left-right direction in FIG. 4 is the relative movement direction RM between the recording unit 16 and the recording medium. In the case of the serial printer 11 </ b> A, the relative movement direction RM is the main scanning direction X of the carriage 31. In the case of the line printer 11B, the relative movement direction RM is the conveyance direction Y of the recording medium P (that is, the movement direction of the conveyance belt 54). In the case of the line printer 11B, the nozzle rows of the same color of the recording heads 17 are positioned so as to be continuously distributed over the entire width direction of the maximum recording medium.

  As shown in FIG. 4, the two data controllers 22 respectively control M (two in the example of FIG. 4) recording heads 17 belonging to different rows among the two head rows in a staggered arrangement. Therefore, the M (two) recording heads 17 belonging to the same column are controlled by the corresponding head controller 23 at the same ejection timing. Thus, even if the position of the relative movement direction RM relative to the recording medium P differs between the two head arrays composed of M recording heads 17 each, the relative movement direction RM on the recording medium P is the same between the head arrays. A dot is printed at the position.

  FIG. 6 is a block diagram showing a detailed electrical configuration of the recording head unit. As shown in FIG. 6, the control unit 14 includes a command analysis unit 61, a position measurement unit 62, and a timer 63. The encoder pulse signal ES from the encoder 25 is also input to the control unit 14.

  The command analysis unit 61 acquires print condition information from the header of the print data PD sent at the beginning of the print job, and acquires “print speed mode designation information” from the print condition information. Further, the command analysis unit 61 interprets a command in the print data PD sent line by line, and a print drive system (excluding the recording head 17) such as the electric motor 24 (see FIG. 1) according to the interpreted command. ) To control. Examples of commands include a paper feed command, a print command, a paper feed command, and a paper discharge command. Note that the print data PD for one line is data that can be printed for one pass (for one main scan) in the case of a serial printer, and for a plurality of nozzle rows in the transport direction in the case of a line printer.

  The position measuring unit 62 is for measuring the relative position between the recording head 17 and the recording medium P. Two encoder pulse signals ES of A phase and B phase with a phase difference of 90 degrees are input to the position measuring unit 62. Specifically, the position measuring unit 62 includes a counter and a direction signal generation circuit (both not shown). The direction signal generation circuit performs a phase comparison process on the A-phase and B-phase encoder pulse signals ES and counters a direction signal indicating whether the relative movement direction RM between the recording head 17 and the recording medium P is the positive direction or the negative direction. Output to. The counter is reset when the relative position between the recording head 17 and the recording medium P is at the origin position, and thereafter, every time a pulse edge is input based on the direction signal when the relative movement direction RM of the both is the positive direction. The counter is incremented by "1" and decremented by "1" each time a pulse edge is input when the relative movement direction RM of both is negative. Thus, the counter of the position measuring unit 62 counts the relative position between the recording head 17 and the recording medium P as a count value based on the origin position.

  When the printer 11 is the serial printer 11A, the position measurement unit 62 measures the position of the recording unit 16 in the main scanning direction X (that is, the same as the carriage position) with the origin when the carriage 31 is at the home position. When the printer 11 is the line printer 11B, the position measurement unit 62 performs recording with the position when the medium detection sensor (not shown) detects the tip of the recording medium P fed onto the conveyor belt 54 as the origin position. The transport position of the medium P is measured.

  The control unit 14 is a region in which the current relative position (for example, a carriage position or a recording medium transport position) between the recording head 17 and the recording medium P measured by the position measuring unit 62 can eject ink droplets determined from print data ( It is discriminated whether it is in the recording area) or other area (non-recording area). Then, when the current relative position between the recording head 17 and the recording medium P is within the non-recording area, the control unit 14 does not eject ink droplets to the ejection driving element 64 provided for each nozzle of the recording head 17. By driving with a weak force, it is determined that a process called “microvibration process” for finely vibrating the ink in the nozzles and preventing ink clogging of the nozzles should be performed.

  The ejection drive element 64 is composed of, for example, a piezoelectric vibration element or an electrostatic drive element. When a voltage pulse having a predetermined drive waveform is applied, the ejection drive element 64 has an inner wall ( The ink droplets are ejected from the nozzles by vibrating and vibrating the ink chamber. Of course, the ejection drive element 64 may be a heater that heats the ink in the nozzle passage, and a system in which ink droplets are ejected from the nozzles using the expansion of bubbles generated by boiling in the ink heated by the heater can be employed.

  Further, during printing by the recording unit 16, the timer 63 discharges ink droplets unrelated to printing in order to periodically remove the thickened ink in the non-ejecting nozzles (pause nozzles). A time interval (for example, a set value within 10 to 30 seconds) for performing a process called “flushing” for refreshing ink is measured.

  Here, the waveform type parameter WP that determines the drive waveform of the voltage pulse to be applied to the ejection drive element 64 includes “print speed mode”, “flushing”, and “fine vibration”. Therefore, when the drive waveform of the voltage to be applied to the ejection drive element 64 is determined, the control unit 14 sends the waveform type parameter WP to the data controller 22.

  When the time measured by the timer 63 reaches the time interval for performing flushing, the control unit 14 sets the recording unit 16 and the recording medium P to a non-opposing position or waits until this position is reached. Thus, flushing is performed in which ink droplets are idlely ejected from all the nozzles of the recording head 17 toward a waste ink recovery unit positioned downward.

  At this time, in the case of the serial printer 11A, the control unit 14 drives the carriage motor 37 (corresponding to the electric motor 24 in FIG. 1) to move the carriage 31 to the home position, and directs each recording head 17 toward the cap 45, for example. Flushing is performed. In the case of the line printer 11 </ b> B, after the recording medium P is discharged to a position not facing the recording unit 16 and the opening formed in the conveying belt 54 reaches a position facing each recording head 17, Then, the control unit 14 causes each recording head 17 to perform flushing toward the waste ink collecting unit that faces each recording head 17 with the opening interposed therebetween. At the time of executing the flushing, the control unit 14 transmits to the data controller 22 the ejection data for flushing and the waveform type parameter WP indicating “flushing”.

  As shown in FIG. 6, the data controller 22 includes M data control units 65 respectively corresponding to the M recording heads 17. The data control unit 65 includes a PLL 66 (Phase Locked Loop) (phase synchronization circuit), a waveform type data generation unit 67, a buffer 68 (buffer memory), and a data transfer module 69. The encoder pulse signal ES input from the encoder 25 to the data controller 22 is input to the PLL 66 in each data control unit 65. The ejection data DI distributed to the recording heads 17 by the distributor 15 and input to the controller 22 is stored in each buffer 68 for one head.

  The PLL 66 shown in FIG. 6 oscillates by applying feedback control to the oscillator in the loop so that the phase difference between the encoder pulse signal ES input as a reference signal from the encoder 25 and the output from the oscillator in the loop is constant. It is an oscillation circuit to be made. This PLL 66 generates a transfer timing signal TS having the same pulse period as that of the input encoder pulse signal ES, or a pulse period of 1/2 or 1/4, and outputs it to the data transfer module 69. Therefore, the pulse period of the transfer timing signal TS has a relationship that it becomes shorter when the relative movement speed between the recording head 17 and the recording medium P becomes faster and becomes longer when the speed becomes slower. The transfer timing signal TS has the same pulse cycle as the printing cycle that determines the printing timing, and determines the pulse cycle of the printing timing signal PTS described later.

  The waveform type data generation unit 67 shown in FIG. 6 refers to the table data TD shown in FIG. 5 stored in a storage unit (not shown) (for example, a memory or a register) based on the waveform type parameter WP input from the control unit 14. Thus, 16-bit waveform type data WD corresponding to the waveform type specified by the waveform type parameter WP is acquired. That is, the waveform type data generation unit 67 converts (encodes) the waveform type specified by the waveform type parameter WP into 16-bit waveform type data by referring to the table data TD.

  Here, the table data TD shown in FIG. 5 will be described. As shown in FIG. 5, the table data TD is a table showing the correspondence between the waveform type parameter WP and the waveform type data WD. The waveform type parameter WP includes “printing speed mode”, “flushing”, and “fine vibration”. Among these, the “printing speed mode” further includes “printing speed mode 1”, “printing speed mode 2”,. , “Printing speed mode Q” is divided into Q types (Q ≧ 2). The waveform type data WD corresponding to each waveform type parameter WP is indicated by 16-bit data. Of course, the data length (number of bits) of the waveform type data WD can be changed as appropriate according to the number of required waveform types, and for example, 8 bits or 32 bits can be adopted.

  The data transfer module 69 shown in FIG. 6 reads discharge data SI for one nozzle row (for example, 180 nozzles) from the discharge data DI stored in the buffer 68, and as a header before the read discharge data SI, Data DATA is generated by attaching the 16-bit waveform type data WD input from the waveform type data generation unit 67. Then, the data transfer module 69 starts the transfer of the data DATA in synchronization with the output of the clock CLK at the transfer timing synchronized with the pulse period of the transfer timing signal TS from the PLL 66. For this reason, the 16-bit waveform type data WD and the 180-bit ejection data SI are transmitted through the same (common) data transfer line SL (common signal line) connecting the substrates 20 and 21 to the encoder pulse signal ES. Are sequentially transferred to the head controller 23 at every transfer timing proportional to the pulse period. As a result, the data DATA is input to the head controller 23 at the timing of each printing cycle TA (see FIG. 7). Here, the printing cycle TA is a dot formation cycle (ink ejection cycle) in the relative movement direction RM between the recording head 17 and the recording medium P. In FIG. 7, as an example, the printing cycle TA is proportional to the pulse cycle of the encoder pulse signal ES. In the present embodiment, the transfer timing of the data DATA corresponds to an instruction related to the injection timing.

  On the other hand, as shown in FIG. 6, the head controller 23 includes a decoder 71, a sequencer 72, a drive waveform signal generation circuit 73, a memory 74, a head DAC (Digital Analog Converter) 75, and a head control unit 76.

  The decoder 71 receives the data DATA from the data transfer module 69 in synchronization with the clock CLK, and decodes the 16-bit waveform type data WD in the header of the received data DATA. Then, the decoder 71 transmits data DATA including the decoded waveform type data WD and the ejection data SI to the sequencer 72.

  In addition, the decoder 71 generates a pulse at every reception timing of the data DATA, thereby generating a print timing signal PTS having the same period as the reception timing of the data DATA and outputting it to the sequencer 72. Therefore, the print timing signal PTS output from the decoder 71 has the same pulse cycle as the print cycle TA. Specifically, the decoder 71 generates a print timing signal PTS by generating a pulse at every reception completion timing of the waveform type data WD received first as a header of the data DATA. In other words, the decoder 71 generates a print timing signal PTS by generating a pulse at every reception start timing of ejection data SI (ejection information) received after the header of the data DATA.

  The sequencer 72 transmits the waveform type data WD of the data DATA received from the decoder 71 to the drive waveform signal generation circuit 73 and transmits the ejection data SI to the head control unit 76.

  Further, when the sequencer 72 receives the print timing signal PTS from the decoder 71 during the reception of the data DATA, the sequencer 72 generates a pulse at a timing synchronized with the input timing, thereby causing the drive waveform signal generating circuit 73 to drive the drive waveform signal COM. A print timing signal PTS serving as a trigger for instructing the generation of is generated and output. At this time, the sequencer 72 outputs the generated print timing signal PTS as a trigger for instructing the head control unit 76 to transfer the ejection data SI.

  The drive waveform signal generation circuit 73 receives the print timing signal PTS at the timing when the waveform type data WD has just been received from the sequencer 72. The drive waveform signal generation circuit 73 that has received the print timing signal PTS reads the waveform condition data WC corresponding to the previously received waveform type data WD from the memory 74. Then, the drive waveform signal generation circuit 73 uses the voltage instruction signal VS indicating the output voltage for generating the drive waveform signal COM of the drive waveform corresponding to the specified waveform type in accordance with the read waveform condition data WC. Output to the DAC 75.

  The head DAC 75 generates and outputs a drive waveform signal COM having a drive waveform corresponding to the designated waveform type by sequentially switching the output voltage to the voltage value designated by the voltage instruction signal VS from the drive waveform signal generation circuit 73. To do.

  On the other hand, the head control unit 76 includes a storage unit (not shown) (for example, a register or a memory) that temporarily stores the received ejection data SI. When the print timing signal PTS from the sequencer 72 is input, the head control unit 76 reads the ejection data SI to be output this time from the storage unit, and outputs the ejection data SI in synchronization with the clock SCLK. At this time, the head control unit 76 generates a print timing signal PTS by generating a pulse in synchronization with the input timing of the print timing signal PTS from the sequencer 72, and outputs it to the head drive circuit 26. Therefore, the print timing signal PTS is output from the head control unit 76 at a pulse period equal to the print period TA.

  Note that the sequencer 72 instructs the drive waveform signal generation circuit 73 to generate a drive waveform signal when the relative position between the recording head 17 and the recording medium P measured by the position measurement unit 62 is reached. Whether to instruct the head control unit 76 to output the print timing signal PTS and the ejection data SI is programmed in advance. For this reason, the sequencer 72 is a little earlier so that ink droplets are ejected from the nozzles of the recording head 17 when the relative position between the recording head 17 and the recording medium P reaches the next print start position. The print timing signal PTS is output at a time interval equal to the print cycle.

Thus, the drive waveform signal COM, the print timing signal PTS, and the ejection data SI are output to the head drive circuit 26 in the recording head 17 via the FCC 46.
As shown in FIG. 6, the head drive circuit 26 includes a shift register 81, a latch circuit 82, a level shifter 83, and a switch circuit 84.

  The shift register 81 receives ejection data SI for one nozzle row. When one nozzle row is, for example, 180 nozzles, 180-bit ejection data SI is input to the shift register 81. Each bit of the discharge data SI represents non-injection / injection of each nozzle. If the value of each bit is “0”, it indicates non-injection, and “1” indicates injection.

  The latch circuit 82 holds the ejection data SI from the shift register 81 until the input of the print timing signal PTS, and synchronizes with the input timing of the print timing signal PTS to the level shifter 83 with the ejection data SI held so far. Output.

  The level shifter 83 functions as a voltage amplifier. When the bit value is “1”, the level shifter 83 outputs an electric signal boosted to a voltage of, for example, about several tens of volts that can drive the switch circuit 84. The drive waveform signal COM from the drive waveform signal generation circuit 73 is supplied to the input side of the switch circuit 84, and the ejection drive element 64 is connected to the output side of the switch circuit 84.

  180 electrical signals that have been boosted / not boosted according to the bit value from the level shifter 83 are input to the switch circuit 84 in parallel. Depending on whether the bit value is “0” or “1”, supply / non-supply of the electrical signal to the switch circuit 84 is selected, so that the switch element corresponding to each injection drive element 64 is turned on in the switch circuit 84. / Off is switched, and a selective supply of voltage to the ejection drive element 64 is performed. For example, when the bit value is “1” in the period of the printing cycle TA, the corresponding switch element in the switch circuit 84 is turned on, and the voltage pulse at that time is supplied to the ejection driving element 64. Ink droplets are ejected from the nozzles. On the other hand, when the bit value is “0” in the period of the printing cycle TA, the corresponding switch element in the switch circuit 84 is turned off, and no voltage pulse is supplied to the ejection drive element 64, so that the ink is discharged from the corresponding nozzle. Drops are not jetted.

  In the case of the serial printer 11 </ b> A, ink droplets are ejected from the nozzles at each ejection position of the recording head 17 in the main scanning direction while the carriage 31 moves in one pass in the main scanning direction X. In this way, printing for one pass is performed, and printing for one page is performed by performing a plurality of passes necessary for printing for one page while feeding paper for each pass.

  On the other hand, in the case of the line printer 11B, the recording medium P on the transport belt 54 driven in the transport direction Y with respect to the fixed recording head 17 is transported in the transport direction Y, and is ejected from the nozzles at each ejection position in the transport direction Y. Ink droplets are ejected. Thus, every time data for one line is latched, printing for one line over the printing width of the recording medium P is continuously performed line by line. Thus, printing is performed by the line recording method.

  FIG. 7 is a timing chart relating to the data transfer process of the recording head unit. In FIG. 7, the data transfer from the data controller 22 (specifically, the internal data transfer module 69) to the head controller 23, the transmission of the drive waveform signal COM from the data controller 22 to the recording head 17, and the transfer of the ejection data SI The timing concerning is shown. Hereinafter, these transfer processes and the like will be described in order from the upstream side on the data transfer path. First, the transfer process of the data transfer module 69 in the data controller 22 will be described, and then the transfer process of the drive waveform signal generation circuit 73 and the head control unit 76 in the head controller 23 will be described. In addition to FIG. 7, the description will be made with reference to FIG. 6 as necessary.

  The data transfer module 69 in the data controller 22 shown in FIG. 6 reads the discharge data SI for the next one nozzle row from the discharge data DI stored in the buffer 68, and uses the waveform as a header before the discharge data SI. Data DATA is generated by attaching the waveform seed data WD acquired from the seed data generation unit 67. When the pulse of the transfer timing signal TS is input from the PLL 66, the data transfer module 69 starts transferring the data DATA. As a result, the data DATA is transferred from the data transfer module 69 to the head controller 23 in synchronization with the clock CLK as shown in FIG. Therefore, the header (waveform type data WD) and the ejection data SI constituting the data DATA are serially transferred from the data transfer module 69 to the head controller 23 through the same data transfer line SL shown in FIG.

  Here, in this example, a configuration in which the control circuit of the recording head is divided into N data control boards 20 and N × M head module boards 21 is adopted. For this reason, it is necessary to transmit encoder pulse period information and waveform type information to the head module substrate 21. At this time, if the configuration in which the encoder signal line and the waveform type data transfer line are connected to the head module substrate is adopted, it is necessary to provide N × M encoder signal lines and waveform type data transfer lines, respectively, and the number of wirings is very large. Become. Therefore, in the present embodiment, the number of wirings is reduced by adopting a configuration in which the encoder pulse signal ES and the waveform type information are sent to the N data control boards 20. In this case, the transmission of the encoder pulse period information from the data control board 20 to the head module board 21 is performed by performing the transfer timing of the data DATA (waveform type data WD and ejection data SI) at a period proportional to the encoder pulse period. A configuration is adopted in which encoder pulse period information is indirectly transmitted from the period of reception timing of data DATA (waveform type data WD and ejection data SI) on the head module substrate 21 side.

  As for the waveform type information, a method of transmitting data DATA, in which the waveform type data WD is added to the ejection data SI as a header, to the head module substrate 21 side by serial transfer from the data control substrate 20 to the head module substrate 21. Is adopted. In this way, since the waveform type data WD is sent by using the data transfer line SL of the ejection data SI, it is possible to avoid the addition of an extra data transfer line dedicated to the waveform type data. Therefore, in this example, it is sufficient to connect one encoder signal line from the encoder 25 and one waveform type data transfer line from the control unit 14 to each data control board 20 (N in total). Yes.

  Also, if the number of times of data DATA transfer in FIG. 7 is # 0, # 1, # 2,..., The data transfer module 69 causes #n waveform type data WDn and # n + 1 ejection data SIn +. Data DATA is generated in combination with 1 (where n = 0, 1, 2,...). That is, the data transfer module 69 generates data DATA by combining the current waveform type data WD and the next ejection data SI. For this reason, as shown in FIG. 7, data DATA composed of a combination of waveform type data WD0 of # 0 and ejection data SI1 of # 1 is transferred. Data DATA consisting of a combination of waveform type data WD1 and # 2 ejection data SI2 is transferred, and data DATA is sequentially transferred for each printing cycle TA in accordance with the same rule.

  In FIG. 7, the recording head 17 is in the non-recording area in the period before # 0, and the recording head 17 is in the recording area in the period after # 1. When performing the ejection control when the recording head 17 is in the non-recording area, the waveform of the fine vibration is selected, and when the recording head 17 performs the ejection control in the recording area, the printing speed mode m (where m is 1 to Q). Waveform of the printing speed mode determined from the printing conditions set at that time) is selected. That is, the waveform type data WD up to # 0 is the waveform of “fine vibration”, and the waveform type data WD from # 1 is the waveform of the printing speed mode m. As shown in FIG. 7, the discharge data SI0 of # 0 transferred before time T0 is for fine vibration, and is, for example, discharge data with all bit values “1”. Then, data DATA consisting of a combination of # 0 “fine vibration” waveform type data WD0 and first # 1 ejection data SI1 in the recording area is transferred.

  At this time, as shown in FIG. 7, the drive waveform signal generation circuit 73 performs a fine cycle designated by the waveform type data WD0 in the printing cycle TA next to the reception timing of the “fine vibration” waveform type data WD0 of # 0. A vibration drive waveform signal COM0 is generated and transmitted. Then, the head drive circuit 26 applies a voltage pulse having a drive waveform based on the received drive waveform signal COM0 to all the ejection drive elements 64, whereby fine vibration when the recording head 17 is in the non-recording area is performed. . As described above, in this embodiment, when the waveform type specified by the waveform type data WD changes from the first waveform to the second waveform, the waveform specifying signal (waveform type data WD) specifying the second waveform. ) Is transmitted at the next cycle (print cycle TA), and a drive waveform (drive waveform signal COM) comprising the second waveform is transmitted.

  For this reason, in the non-recording area, data DATA consisting of a combination of the waveform type data WDn for designating the waveform of the micro-vibration and the ejection data SIn + 1 is sequentially transferred, and when entering the recording area from the non-recording area, the waveform type Waveform designation content by data WD changes from “micro vibration” to “printing speed mode m”, and a drive waveform signal is generated at the printing cycle TA next to the printing cycle TA that received the waveform type data WD with the changed designated waveform. The circuit 73 generates the drive waveform signal COM with the waveform of the “printing speed mode” after the change.

  When the recording head 17 performs printing in the recording area, data DATA consisting of a combination of waveform type data WDn specifying the waveform of “printing speed mode m” and ejection data SIn + 1 is received from the data transfer module 69. The data is sequentially transferred to the head controller 23. The drive waveform signal generation circuit 73 in the head controller 23 is designated by the waveform type data WDn in the printing cycle TA next to the printing cycle TA that has received the waveform type data WDn designating the waveform of the “printing speed mode m”. A drive waveform signal COMn is generated with a waveform of “print speed mode m” and transmitted to the head drive circuit 26. As a result, the drive timing of the recording head 17 is controlled based on the drive waveform signal COMn, and ink droplets are ejected, for example, at every print cycle TA.

  Further, when the recording head 17 moves from the recording area to the non-recording area, the waveform type specified by the waveform type data WD in the data DATA transferred from the data transfer module 69 is changed from “print speed mode m” to “fine”. Changes to “vibration”. At this time, the drive waveform signal generation circuit 73 receives the waveform type data WD in which the “microvibration” waveform is specified, and the printing cycle TA next to the printing cycle TA receives the waveform type data WD specified by the waveform type data WD. A drive waveform signal COM is generated with a waveform of “fine vibration” and transmitted to the head drive circuit 26. As a result, when the recording head 17 is in the non-recording area and printing is not performed, the recording head 17 vibrates slightly.

  Further, during printing, when the timer 63 finishes counting the time interval for flushing and the flushing time comes, the data transfer module 69 sets the waveform type data WDn for designating “flushing” and the bit values of all “1”. Data DATA composed of a combination with the flushing discharge data SIn + 1 is transferred to the head controller 23. When the waveform designated by the waveform type data WD changes from the “printing speed mode m” or “microvibration” waveform (first waveform) to the “flushing” waveform (second waveform), the “flushing” In the printing cycle TA next to the printing cycle TA that has received the waveform type data WD designating the waveform type data WD, the driving waveform signal generation circuit 73 generates the driving waveform signal COM with the “flushing” waveform designated by the waveform type data WD. Then, the data is transmitted to the head drive circuit 26. As a result, in the flushing position where the recording head 17 is located immediately above the waste ink collecting unit, flushing is performed in which ink droplets are ejected from the nozzles of the recording head 17 toward the waste ink collecting unit.

  On the other hand, the decoder 71 shown in FIG. 6 sends the data DATA received from the data transfer module 69 to the sequencer 72 while decoding the waveform type data WD. At this time, the decoder 71 generates a pulse at every reception completion timing of the 16-bit header (waveform type data WD), thereby synchronizing the reception completion timing and printing timing signal PTS having a pulse period equal to the printing period TA. And the generated print timing signal PTS is output to the sequencer 72.

  At the pulse input time of the print timing signal PTS in the sequencer 72, the waveform type data WDn of #n is almost sent to the drive waveform signal generation circuit 73, and the ejection data SIn of the previous #n is already the head control unit. 76. Then, the sequencer 72 generates the print timing signal PTS with a period synchronized with the pulse period of the input print timing signal PTS and outputs it to the drive waveform signal generation circuit 73 and the head control unit 76. The print timing signal PTS serves as a trigger for instructing the drive waveform signal generation circuit 73 to start generation of the drive waveform signal COM, and as a trigger for instructing the head control unit 76 to start transfer of the ejection data SI.

  When the print timing signal PTS is input, the drive waveform signal generation circuit 73 shown in FIG. 6 reads the waveform condition data WC corresponding to the waveform type data WD from the memory 74, and outputs a voltage instruction signal to the head DAC 75 according to the waveform condition data WC. Output. The head DAC 75 generates the drive waveform signal COM by outputting the voltage instructed by the voltage instruction signal, and transmits it to the head drive circuit 26. For example, if the waveform type data WD is “fine vibration”, the drive waveform signal COM having the same waveform as the drive waveform signal COM0 shown in FIG. If the waveform type data WD is “printing speed mode m”, a drive waveform signal COM having the same waveform as the drive waveform signal COM1 shown in FIG. 7 is transmitted from the head DAC 75.

  Here, the waveform condition data WC stored in the memory 74 shown in FIG. 6 is condition data for forming the waveform of the drive waveform signal COM. In the waveform condition data WC, an elapsed time from the generation start time of the drive waveform signal COM (start time of the printing cycle TA), an instruction voltage, a waveform inclination, a voltage holding time, and the like are defined. For example, in the example of FIG. 7, after the generation of the drive waveform signal COM1, the voltage is increased at a predetermined slope from time to to t1, and then held at a constant voltage from time t1 to time t2, and thereafter from time t2. The waveform condition data WC is set so that the voltage is decreased at a predetermined slope from time t3, held at a constant voltage from time t3 to time t4, and further increased at a predetermined slope from time t4 to time t5. Yes.

  In the “flushing” waveform condition data WC, a waveform condition close to the waveform condition of “printing speed mode m” is predetermined. For example, the “flushing” waveform condition data WC forms the same waveform as the maximum waveform (waveform at the time of printing) in the “printing speed mode” or a waveform stronger than the maximum waveform (a waveform with a large voltage change). The waveform conditions are defined as follows. Further, the waveform condition data WC of “fine vibration” is a waveform (a waveform with a small voltage change) that is sufficiently weaker than any waveform in the “printing speed mode” (waveform at the time of printing) and cannot eject ink droplets. The waveform conditions are defined so as to form, and the waveform of the drive waveform signal COM0 of “fine vibration” in FIG. 7 is set to be formed.

  On the other hand, the head control unit 76 shown in FIG. 6 outputs the print timing signal PTSn in a cycle synchronized with the pulse cycle of the print timing signal PTS input from the sequencer 72, and the current # n + 1 ejection data SIn + 1. Start transferring. At this time, as shown in FIG. 7, the printing cycle TA starts at the timing of the rising edge of the pulse of the print timing signal PTSn, and the generation of the drive waveform signal COMn is started. Here, as shown in FIG. 7, the print timing signal PTSn is predetermined with respect to the reception completion timing (substantially the same timing as the pulse rising edge of the encoder pulse signal ES) of the header (waveform type data WD) of the data DATA. Although the time ΔT is delayed, the predetermined time ΔT corresponds to the time required for the internal processing of the head controller 23. As described above, the head controller 23 transmits the drive waveform signal COM at a timing when a predetermined time ΔT has elapsed from the completion of reception of the waveform type data WD.

  The ejection data SIn of #n is latched by the latch circuit 82 until the print timing signal PTSn is input to the latch circuit 82 as a latch signal. When the print timing signal PTSn is input to the latch circuit 82, the #n ejection data SIn that has been latched until then is output to the level shifter 83. Further, when the bit value of the ejection data SIn is “1”, the level shifter 83 boosts the voltage, so that the injection drive element 64 corresponding to the switch element to which the boosted voltage in the switch circuit 84 is applied is applied. Is applied with a voltage pulse having a drive waveform corresponding to the drive waveform signal COMn. As a result, the ejection driving element 64 corresponding to the bit value “1” is driven. For example, in the printing speed mode m, ink droplets are ejected from the corresponding nozzle.

As described above, according to the present embodiment, the following effects can be obtained.
(1) Data DATA is transferred from the data control board 20 to the head module board 21 at a period synchronized with the pulse period of the encoder pulse signal ES, and the head module board 21 side receives the encoder pulse signal ES from the period of the data DATA reception timing. The period corresponding to the printing period TA proportional to the pulse period can be known. Therefore, it is sufficient to connect the signal line of the encoder 25 only to the data control board 20, the connection of the encoder signal line to each head module board 21, and the transmission of encoder pulse cycle information between the data control board 20 and each head module board 21. There is no need to provide a dedicated signal line.

  (2) The data DATA with the header added to the ejection data SI is transferred from the data control board 20 to the head module board 21, and the cycle of the encoder pulse signal ES is determined by the period of the header reception completion timing on the head module board 21 side. Information is transmitted to the head module substrate 21. Therefore, if a pulse is generated at a period synchronized with the reception completion timing period of the header, the print timing signal PTS having a pulse period synchronized with the print period TA can be generated on the head module substrate 21 side. Therefore, the print timing signal PTS can be generated even if the encoder pulse signal ES is not directly input to the head module substrate 21 side. For example, if the configuration is based on a predetermined timing during header reception, a timing process that measures the elapsed time from the header reception start time may be required, but the header reception completion timing is adopted. Therefore, the timing for each predetermined period (printing period TA) proportional to the encoder pulse period can be acquired on the head module substrate 21 side without performing such a timing process.

  (3) Since the waveform type data WD is transferred in the header attached to the discharge data SI (injection information), the waveform type data WD is diverted by using the data transfer line SL (serial transfer line) for the discharge data SI. Can be transferred. The head controller 23 then transmits the drive waveform signal COM at a timing based on the reception timing of the waveform type data WD (waveform designation signal). Therefore, it is not necessary to separately provide a dedicated data transfer line for transferring the waveform type data WD between the data control board 20 and the head module board 21. Therefore, also from this point, the number of wirings connected to the substrates 20 and 21 can be reduced. Therefore, the recording head unit including the recording unit 16 and the substrates 20 and 21 has a relatively simple wiring structure, and the recording head unit can be assembled relatively easily.

  (4) The decoder 71 on the head module substrate 21 side generates the print timing signal PTS at a period synchronized with the reception completion timing of the header (waveform type data WD). For this reason, it is possible to immediately generate the drive waveform signal COM having the designated waveform immediately after receiving the waveform type data WD. For example, if a configuration in which the print timing signal PTS is generated at a timing earlier than the reception completion timing of the waveform type data WD, the acquisition of the necessary waveform type data WD at the start of the printing cycle TA is not in time. In this case, the use of the waveform type data WD must be waited until the next printing cycle TA, and the storage area (memory area or register) is doubled so that two waveform type data WD can be held. There is also a worry. However, according to the present embodiment, since the pulse of the print timing signal PTS is generated in accordance with the reception completion timing of the waveform type data WD, the holding time of the waveform type data WD can be sufficiently shortened compared to the printing cycle TA, which is necessary. The storage area can be of a relatively small size that can hold one waveform type data.

  (5) Since connection of the encoder signal line to the head module board 21 is not required, a plurality (M pieces) of the head module board 21 can be connected to one data control board without worrying about an increase in signal lines. (M ≧ 2)). Therefore, since the number of connected head module substrates 21 per data control substrate can be selected within a range of a maximum of M, a recording head unit can be configured without wasting a circuit.

  (6) The drive waveform signal generation circuit 73 (waveform generation unit) transmits the drive waveform signal COM of the designated waveform type at a period synchronized with the reception period of the waveform type data WD (waveform instruction). At this time, when the waveform specified by the waveform type data WD changes from the first waveform to the second waveform, the drive waveform signal generation circuit 73 receives the waveform type data WD specifying the second waveform. The drive waveform signal COM is transmitted with the second waveform from the printing cycle TA next to TA. Therefore, the drive waveform signal COM can be transmitted with the second waveform designated immediately after the next printing cycle TA. Therefore, the waiting time from when the waveform specified by the waveform type data WD changes until the drive waveform signal COM having the changed waveform is transmitted can be shortened. For example, since the holding time for holding the waveform type data WD specifying the waveform of the drive waveform signal COM generated in the next printing cycle TA is shortened, the storage area for holding the waveform type data WD is reduced. The size can be reduced.

The said embodiment is not limited above, It can also change into the following aspects.
The predetermined time ΔT can be changed as appropriate. In this case, the predetermined time ΔT is not limited to the time required for internal processing of the head controller 23 (internal processing time). As shown in FIG. 8, the predetermined time ΔT can be set longer than the internal processing time. For example, a timing means such as a timer (time counter) is provided in the head controller 23, and the generation of the drive waveform signal COM is performed after a predetermined time ΔT has elapsed from the reference time when the reception of the waveform type data WD in the data DATA is used as a reference. The generation (transmission) of the drive waveform signal COM may be started when the set time (= predetermined time ΔT−internal processing time) has been counted. According to this configuration, the predetermined time ΔT shown in FIG. 8 can be appropriately adjusted within the range of the internal processing time and the printing cycle TA. For example, the transmission timing of the #n drive waveform signal COM and the print timing signal PTSn can be adjusted in accordance with the transmission timing of the #n ejection data SIn from the head controller 23, so that the ejection in the head drive circuit 26 in the recording head 17 can be performed. It is possible to avoid a situation where the latch timing of the data SIn is further delayed by one printing cycle TA. In the present specification, the predetermined time ΔT may include zero when the internal processing time can be ignored.

  As shown in FIG. 9, with reference to the reception start timing of the waveform type data WD (header), the time when a predetermined time ΔT has elapsed from the reference time is used as the generation start timing (transmission start timing) of the drive waveform signal COM. Can be adopted. In this case, the data DATA is composed of a combination of #n waveform type data WDn and #n ejection data SIn, and is driven in the printing cycle TA next to the printing cycle TA that received the waveform type data WDn (waveform designation signal). Generation (transmission) of the waveform signal COMn is performed.

  -It is also possible to perform gradation printing in which the dot size can be selected step by step instead of the two gradations (the presence or absence of ejection) of only one kind of dot size. For example, as described in Patent Document 1, ink droplets may be ejected with four gradations of large, medium, and small dot sizes. In this case, the drive waveform signal COM described in, for example, Patent Document 1 may be used, and the drive waveform signal COM may be transmitted at a period synchronized with the reception timing of the waveform type data WD. Of course, gradation printing of other gradation numbers such as 5 gradations and 8 gradations can also be adopted. In this case, if SP data (selected waveform designating data) designating one or a plurality of waveforms to be selected from among a plurality of waveforms constituting the drive waveform signal COM as in Patent Document 1, the ejection data SI is attached. Good.

The target (recording medium) is not limited to paper, and may be a resin film, a metal film, a cloth, an optical disk such as a CD or a DVD, a magnetic disk, or a circuit board.
In the above-described embodiment, the fluid ejecting apparatus is embodied as an ink jet printer. However, the fluid ejecting apparatus may be applied to a fluid ejecting apparatus that ejects droplets as fluid other than ink. Here, the droplet refers to the state of the liquid ejected from the fluid ejecting apparatus, and includes a liquid that is tailed in a granular shape, a tear shape, or a thread shape. The fluid may be any material that can be ejected by the fluid ejecting apparatus. For example, the substance may be in a liquid state, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvent, organic solvent, solution, liquid resin, liquid metal (metal melt) It includes not only a liquid in a flow state or a state of a substance, but also particles in which functional material particles made of solid substances such as pigments and metal particles are dissolved, dispersed or mixed in a solvent. Further, representative examples of the liquid include ink and liquid crystal. Here, the ink includes various liquid compositions such as general water-based ink and oil-based ink, gel ink, and hot-melt ink. Further, the fluid includes powdered fluid. An example of the powder is a toner. As a specific example of the fluid ejecting apparatus, for example, a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, a color filter, or the like in a dispersed or dissolved state. Fluid ejecting apparatus for ejecting onto a medium (target) such as a substrate, fluid ejecting apparatus for ejecting bio-organic matter used for biochip production onto the medium, fluid ejecting apparatus for ejecting liquid as a sample to be used as a precision pipette, and textile printing An apparatus, a micro dispenser, etc. may be sufficient. Furthermore, UV curing is used to form fluid injection devices that inject lubricant at pinpoints while transporting precision machines (targets) such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. A fluid ejecting apparatus that ejects a transparent resin liquid such as resin onto a substrate (target), or a fluid ejecting apparatus that ejects an etching solution such as an acid or an alkali to etch a target such as a substrate may be employed. In addition, the fluid referred to in this specification does not include a fluid composed only of gas.

  DESCRIPTION OF SYMBOLS 11 ... Printer as fluid ejecting apparatus, 11A ... Serial printer as fluid ejecting apparatus, 11B ... Line printer as fluid ejecting apparatus, 12 ... Communication I / F, 13 ... Buffer, 14 ... Control part, 15 ... Distributor, DESCRIPTION OF SYMBOLS 16 ... Recording unit, 17 ... Recording head as fluid ejection head, 17K, 17C, 17M, 17Y ... Nozzle array, 20 ... Data control board (upper board) as ejection instruction device and ejection instruction unit, 21 ... Drive waveform generation Head module substrate (lower substrate) as device and waveform generation unit, 22... Data controller as injection instruction device and injection instruction unit, 23... Head controller as drive waveform generation device and waveform generation unit, 24. ... Encoder, 25A ... Linear scale, 25B ... Sensor, 26 Head drive circuit, 28 ... Linear encoder, 31 ... Carriage, 37 ... Carriage motor, 43 ... Paper feed motor, 44 ... Maintenance device, 45 ... Cap, 51-53 ... Roller, 54 ... Conveyor belt, 55 ... Roller, 56 ... Conveyance motor 61 ... Command analysis unit 62 ... Position measurement unit 63 ... Timer, 64 ... Injection drive element, 65 ... Data control unit, 66 ... PLL, 67 ... Waveform type data generation unit, 68 ... Buffer, 69 ... Data Transfer module 71 ... Decoder, 72 ... Sequencer, 73 ... Drive waveform signal generation circuit constituting waveform generation unit, 74 ... Memory constituting waveform generation unit, 75 ... Head DAC constituting waveform generation unit, 76 ... Head control Unit: 81 ... Shift register, 82 ... Latch circuit, 83 ... Level shifter, DESCRIPTION OF SYMBOLS 4 ... Switch circuit, 100 ... Host device, 101 ... Main body, 102 ... Monitor, 103 ... Input device, P ... Recording medium (paper) as target, SL ... Data transfer line (common signal line), ES ... Encoder pulse Signal: DATA: Instruction relating to ejection timing of fluid ejection head, waveform instruction for instructing drive waveform, data as data including waveform instruction, COM: drive waveform signal as drive waveform, WD: waveform type data as waveform instruction (Header), SI ... discharge data (injection information), TD ... table data, WP ... waveform type parameter as waveform information, PTS ... print timing signal, TA ... print cycle, WC ... waveform condition data, .DELTA.T ... predetermined time.

Claims (5)

A fluid ejecting head for ejecting fluid;
An ejection instructing unit that receives waveform information related to a driving waveform for driving the fluid ejecting head, and performs an instruction relating to an ejection timing of the fluid ejecting head and a waveform instruction for instructing the driving waveform through a common signal line;
A waveform generation unit configured to generate a drive waveform and supply the fluid ejection head to the fluid ejection head at the instructed timing based on an instruction regarding the ejection timing of the fluid ejection head received through the common signal line and a waveform instruction instructing a drive waveform; ,
A fluid ejecting apparatus comprising:   The fluid ejecting apparatus according to claim 1, wherein a timing at which data including the waveform instruction is transmitted is an instruction of an ejection timing of the fluid ejecting head.   A plurality of the waveform generation units are provided, and the ejection instruction unit individually instructs each of the plurality of waveform generation units with respect to the ejection timing of the fluid ejection head and a waveform instruction for instructing a drive waveform. Item 3. The fluid ejection device according to Item 1 or 2. A fluid ejecting head control method in a fluid ejecting apparatus including a fluid ejecting head for ejecting fluid,
A step in which the ejection instructing unit receives waveform information relating to a driving waveform for driving the fluid ejecting head, and performs an instruction relating to the ejection timing of the fluid ejecting head and a waveform instruction instructing the driving waveform through a common signal line;
The waveform generation unit generates a drive waveform based on the instruction regarding the ejection timing of the fluid ejection head received through the common signal line and the waveform instruction that instructs the drive waveform, and supplies the drive waveform to the fluid ejection head at the instructed timing. And steps to
A fluid ejecting head control method in a fluid ejecting apparatus. A drive waveform generating device for a fluid ejecting head having a waveform generating unit that generates a drive waveform for driving the fluid ejecting head and supplies the generated drive waveform to the fluid ejecting head,
The waveform generation unit receives waveform information related to a driving waveform for driving the fluid ejecting head, and performs an instruction regarding a timing of ejecting the fluid ejecting head and a waveform instruction for instructing a driving waveform through a common signal line. A drive waveform is generated and supplied to the fluid ejecting head at the instructed timing based on the instruction regarding the ejection timing of the fluid ejecting head received through the common signal line and the waveform instruction instructing the drive waveform. A drive waveform generator for a fluid ejecting head.

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