JP2010228231A - Head drive device and fluid ejecting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve the versatility of a head drive device. <P>SOLUTION: A head drive device includes a control part. If receiving data to allow a head, which ejects fluid, to eject fluid, the control part analyzes a frequency of the data and processes the received data according to the frequency to allow the head to eject fluid on the basis of the processed data. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a head driving device and a fluid ejecting apparatus.

  2. Related Art Ink jet printers (hereinafter referred to as printers) that print an image by ejecting ink from a head unit according to data from a head driving device to a medium are known. The printer has a controller that performs various controls for printing an image, and the controller transmits print data for ejecting ink from the head unit to the head unit (see, for example, Patent Document 1). However, the transmission method differs depending on the printer model, that is, the type of controller provided in each printer, and if the print data transmission method of the controller is different, the processing of the head unit on the side that receives the print data is also performed. Come different. Therefore, it is necessary to design the head unit as a dedicated product according to the print data transmission method of each controller.

JP 2004-330462 A

Printer manufacturers produce many types of printers, and the types of controllers often differ for each type of printer. Therefore, many types of head units must be manufactured in accordance with the types of printers, and the manufacturing of the head units is costly.
Accordingly, an object of the present invention is to generalize the head drive device.

The main invention for solving the above problems is that when data for ejecting fluid is received from a head that ejects fluid, the frequency of the data is analyzed, and the received data is processed according to the frequency, A head driving device comprising: a control unit that ejects fluid from the head based on the data.
Other features of the present invention will become apparent from the description of this specification and the accompanying drawings.

1 is a block diagram illustrating a printing system. It is a block diagram explaining a head unit. FIG. 3A is a sectional view of a part of the head unit, and FIG. 3B shows a nozzle row. It is a block diagram for demonstrating a head control part. 2 shows a flow of print data in a head controller. 6A is a diagram for explaining an output buffer, FIG. 6B is a diagram illustrating a case where the unit data amount N is 180, and FIG. 6C is a diagram illustrating a case where the unit data amount N is 360. FIG. 7A to FIG. 7C are diagrams showing the difference in the print data transmission method. FIG. 8A is a diagram showing a flow of processing of received data, FIG. 8B is a table showing control signals corresponding to frequencies, It is a figure explaining a data processing part. It is a figure explaining the processing method of 1st received data. FIG. 11A is a diagram for explaining a method of processing the second received data, FIG. 11B is a diagram showing a potential input to each input unit, and FIG. 11C is a differential circuit 74 when the first control signal is 1. FIG. FIG. 12A is a diagram for explaining a method of processing the third received data, and FIG. 12B is a diagram showing a reference potential when determining the data level of the received data. It is a figure for demonstrating switching of the processing method of 2nd received data and 3rd received data. It is a figure which shows the modification of a 2nd 3rd data processing part. The table regarding a 3rd control signal is shown. FIG. 16A and FIG. 16B are diagrams showing the difference in operation of the shift register group due to the difference in received data.

=== Summary of disclosure ===
At least the following will become apparent from the description of the present specification and the accompanying drawings.

That is, when data for ejecting fluid is received from a head that ejects fluid, the frequency of the data is analyzed, the received data is processed according to the frequency, and the head is based on the processed data. A head driving device having a control unit for ejecting fluid.
According to such a head drive device, the head drive device can be generalized, and processing of received data can be switched automatically.

In this head driving device, the control unit includes a comparison circuit and a differential circuit, determines a control signal corresponding to the frequency of the received data, and uses the control signal to compare the comparison circuit and the differential circuit. Either of the above is operated to process the received data.
According to such a head drive device, the head drive device can be generalized, and received data can be processed by a correct circuit.

In such a head drive device, the control unit receives (1) the received data by inputting the received data to the comparison circuit when the frequency of the received data is the first frequency. When the data potential is equal to or higher than the first reference potential, the first potential is output. When the received data potential is less than the first reference potential, the second potential is different from the first potential. Output data for outputting a potential is acquired, and (3) ejecting fluid from the head based on the output data.
According to such a head drive device, it is possible to convert the received data into output data from which the data level can be determined.

In this head driving device, the control unit (1), when the frequency of the received data is the second frequency, (2) the data received at the first input unit of the differential circuit. Based on the difference between the data potential input to the first input unit and the constant potential input to the second input unit by inputting and inputting a constant potential to the second input unit of the differential circuit When the potential is equal to or higher than the second reference potential, the first potential is output. When the potential based on the difference is less than the second reference potential, the second potential different from the first potential is output. Acquiring data, and (3) ejecting fluid from the head based on the output data.
According to such a head drive device, it is possible to convert the received data into output data from which the data level can be determined.

In such a head drive device, the control unit (1), when the frequency of the received data is a third frequency, (2) the data received at the first input unit of the differential circuit; The non-inverted signal is input, and the inverted signal of the received data is input to the second input unit of the differential circuit, whereby the potential of the non-inverted signal input to the first input unit and the When the potential based on the difference from the potential of the inverted signal input to the second input unit is greater than or equal to the third reference potential, the first potential is output, and the potential based on the difference is less than the third reference potential. In some cases, output data that outputs a second potential different from the first potential is acquired, and (3) fluid is ejected from the head based on the output data.
According to such a head drive device, it is possible to convert the received data into output data from which the data level can be determined.

In such a head drive device, when data transmitted by differential transmission is received, a non-inverted signal of the received data is input to the first input unit of the differential circuit, and the differential circuit Inverted signal of the received data is input to the second input unit and processed, and the L-level potential is shifted from the ground potential to a predetermined potential, and the data transmitted by single-ended transmission is received. If received, the received data is input to the first input section of the same differential circuit, and a constant potential is input to the second input section of the same differential circuit for processing.
According to such a head driving device, the circuit configuration can be simplified.

In this head driving device, the head includes a first nozzle group that is a plurality of nozzles that eject fluid, a second nozzle group that is a plurality of nozzles that eject fluid, and fluid ejection of the first nozzle group. A first data storage unit that stores the data regarding, a second data storage unit that stores the data regarding fluid ejection of the second nozzle group, and the data processed according to the frequency of the received data. An input unit that is input, and the control unit receives the data input to the input unit according to the frequency of the received data, and stores the data in the first data storage unit and the second data storage unit. A first process to be stored in one of them and a second process to store the data input to the input unit in the first data storage unit and the second data storage unit are selectively performed.
According to such a head drive device, it is possible to eject a fluid from the nozzle with correctly corresponding data.

Further, (1) when receiving a fluid ejecting head and data for ejecting the fluid from the head, the frequency of the data is analyzed, the received data is processed according to the frequency, and the processed And (2) a main control unit that is communicably connected to the head driving device and ejects the fluid from the head. And a main control unit that transmits the data for the head driving device to the head driving device, and (3).
According to such a fluid ejecting apparatus, the head driving device can automatically switch the processing of the received data in accordance with the data transmission method from the main control unit.

=== Configuration of inkjet printer ===
Hereinafter, an embodiment will be described by taking a printing system in which the fluid ejecting apparatus is an inkjet printer (printer 1) and the printer 1 and the computer CP are connected as an example.

  FIG. 1 is a block diagram showing a printing system. The printer 1 includes a paper transport mechanism 10, a carriage movement mechanism 20, a drive signal generation circuit 30, a head unit 40, various sensors 50, and a printer-side controller 60.

  The paper transport mechanism 10 transports the paper in the transport direction. The carriage moving mechanism 20 moves the head unit 40 in a predetermined movement direction. The drive signal generation circuit 30 generates a drive signal COM for operating the piezo element 431 (see FIG. 3) included in the head unit 40. The head unit 40 ejects ink toward the paper. Each sensor 50 monitors the status of the printer 1. The detection result by each sensor 50 is output to the printer-side controller 60 and performs overall control in the printer 1. The printer-side controller 60 (corresponding to a main control unit) includes an ASIC 61 and a main body side memory 62, and the ASIC 61, the main body side memory 62, and the drive signal generation circuit 30 are mounted on the main body side substrate CB.

<About the head unit 40>
2 is a block diagram for explaining the head unit 40, FIG. 3A is a sectional view of a part of the head unit 40, and FIG. 3B shows a nozzle row. The head unit 40 includes a head control unit HC (corresponding to a control unit) and a head HD (head-side cable 46, relay board 47). The main body side substrate CB and the head unit 40 are electrically connected by a flat cable FC having flexibility.

  As illustrated in FIG. 3A, the head HD includes a case 41, a flow path unit 42, and a piezo element group 43. The case 41 accommodates and fixes the piezo element group 43 in the accommodating space 411. Further, the accommodating space 411 accommodates the head controller HC and the head side cable 46. A flow path unit 42 is joined to the front end surface of the case 41. The flow path unit 42 is provided with a series of ink flow paths from the common ink chamber 421 to the nozzle 424 through the ink supply path 422 and the pressure chamber 423. When the printer 1 is used, the ink flow path is filled with ink. Then, an ink droplet is ejected from the nozzle 424 due to a change in the pressure of the ink applied in the pressure chamber 423.

  As shown in FIG. 3B, the nozzles 424 are provided at a predetermined pitch D in a predetermined direction, and constitute a nozzle row. An ink flow path is provided for each nozzle. Here, the head HD has a nozzle row of 368 nozzles. Among these nozzles 424, the first to fourth nozzles and the 365th to 368th nozzles constitute a dummy nozzle group. Each piezo element 431 is deformed by application of the drive signal COM and changes the volume of the corresponding pressure chamber 423. As a result, a pressure change is applied to the ink in the pressure chamber 423.

  The head controller HC has a control IC 44 and a memory IC 45 and is mounted on the head side cable 46. The head side cable 46 electrically connects each piezo element 431 of the head HD and the relay substrate 47. The head side cable 46 is constituted by a flexible film-like wiring member, for example, a wiring member having a core wire sandwiched between films having electrical insulation properties. Each core wire of the head side cable 46 is also connected to the head controller HC (control IC 44, memory IC 45). The relay board 47 is provided between the head side cable 46 and the flat cable FC, and electrically connects the head side cable 46 and the flat cable FC. As a result, the printer-side controller 60 and the drive signal generation circuit 30, the head controller HC, and each piezo element 431 are electrically connected.

=== Ink Ejection from Head HD ===
FIG. 4 is a block diagram for explaining the head controller HC, and FIG. 5 shows a flow of print data in the head controller HC. The control IC 44 included in the head controller HC includes a control logic 441, a shift register group 442, a latch circuit group 443, a decoder group 444, and a switch group 445.

The control logic 441 stores switch operation data SP for determining the operation of each switch 445a included in the switch group 445. The switch operation data SP in the printer 1 is composed of, for example, four types of data q0 to q3. These data q0 to q3 are output to each decoder 444a included in the decoder group 444. Then, the data selected by the decoder 444a is output to the corresponding switch 445a.
The control logic 441 includes a data processing unit 446. The data processing unit 446 outputs a predetermined amplitude (for example, a signal having an H level of 3.3 V and an L level of 0 V) as print data having different transmission methods (for example, data having different amplitudes).

  In the shift register group 442, dot formation data SI determined for each nozzle 424 is set. The dot formation data SI is data for determining the ejection amount of ink droplets for each nozzle 424, and is a kind of control data used when controlling the ejection of liquid. In this printer 1, the dot formation data SI is composed of 2-bit data. For this reason, the ejection amount of ink droplets can be determined in four stages. For example, data [00] indicates non-ejection of ink droplets, and data [01] indicates that an amount of ink droplets suitable for forming small dots is ejected. Similarly, data [10] indicates that an amount suitable for forming a medium dot, and data [11] indicates that an ink droplet of an amount suitable for formation of a large dot is ejected.

  The shift register group 442 includes a group of an upper shift register 442a that stores upper bits of the dot formation data SI and a lower shift register 442b that stores lower bits of the dot formation data SI for each of the plurality of nozzles 424. Have.

  The latch circuit group 443 includes a plurality of latch circuits, and latches dot formation data SI set in each shift register included in the shift register group 442. Like the shift register group 442, the latch circuit group 443 includes a set of an upper latch circuit 443a and a lower latch circuit 443b for each of the plurality of nozzles 424. The upper latch circuit 443a latches the upper bits of the dot formation data SI set in the upper shift register 442a at a timing defined by a latch signal sent from the printer controller 60. The lower latch circuit 443b latches the lower bits of the dot formation data SI set in the lower shift register 442b at a timing defined by the latch signal. By being latched by the upper latch circuit 443a and the lower latch circuit 443b, the dot formation data SI set in the shift register group 442 is set for each nozzle 424. The latched dot formation data SI is input to each decoder 444a.

  The decoder group 444 includes a plurality of decoders 444a. The decoder 444a is provided for each nozzle 424, and selects the switch operation data SP (q0 to q3) from the control logic 441 based on the dot formation data SI latched by the corresponding latch circuit sets 443a and 443b. To do. For example, the decoder 444a is set to select data q0 as the switch operation data SP when the dot formation data SI is data [00]. Then, the decoder 444a outputs the selected switch operation data SP to the corresponding switch 445a. Therefore, the decoder 444a is a kind of switch operation data output unit.

  The switch group 445 also includes a plurality of switches 445 a provided for each nozzle 424. Each switch 445a is controlled to be turned on / off based on the switch operation data SP. When the switch 445a is on, the drive signal COM is applied to the piezo element 431. Further, when the switch 445a is in the OFF state, the drive signal COM is not applied to the piezo element 431. As a result, the drive waveform of the drive signal COM is applied to or blocked from the piezo element 431. The piezo element 431 gives a pressure change to the ink in the pressure chamber 423 in accordance with the potential change of the applied drive waveform. As a result, ink droplet ejection control is performed according to the content of the dot formation data SI.

  Further, as shown in FIG. 2, the memory IC 45 included in the head control unit HC is electrically connected to the printer-side controller 60 through the head-side cable 46, the relay board 47, the flat cable FC, and the like. The memory IC 45 is connected to the control IC 44 via the head side cable 46 so as to be communicable. Note that the memory IC 45 has a frequency analysis unit 451 described later.

=== About the print data transmission method ===
<About the data transmission unit 651 of the controller>
As shown in FIG. 1, the control unit 65 of the controller 60 includes a “data transmission unit 651” that transmits dot formation data SI, which is data relating to ink ejection of each nozzle, to the head HD.

  FIG. 6A is a diagram for explaining an output buffer 652 included in the data transmission unit 651. As shown in FIG. 1, the data transmission unit 651 includes an output buffer 652 and a write transmission control unit 653. The write transmission control unit 653 reads out the dot formation data SI received from the computer CP by the printer 1 and stored in the main body side memory 62, and writes the read dot formation data SI into the output buffer 652. Then, the write transmission control unit 653 transmits the dot formation data SI written in the output buffer 652 to the head HD for each predetermined data amount (unit data amount).

  The unit data amount (number of bits, DataLength) of the dot formation data SI transmitted from the write transmission control unit 653 to the head HD is determined according to the configuration of the output buffer 652. In the output buffer 652, as shown in FIG. 6A, “N words (pixels)” in the direction corresponding to the nozzle row direction (hereinafter referred to as nozzle row direction) on the data and in the direction intersecting the nozzle row on the data. Data of “8 words (pixels)” in total (N × 8 words (pixels)) can be stored in a corresponding direction (hereinafter, crossing direction).

  One word (one pixel) of data is assigned to one nozzle Nz. As described above, since the dot formation data SI per word (one pixel) is “2 bits”, the output buffer 652 can store a total of “N × 16 bits” data. For the sake of explanation, as shown in the figure, the data stored in the output buffer 652 is “SI (1), SI (2),... SI (N ) ”, And in order from the left in the cross direction,“ 1 column, 2 columns,..., 8 columns ”is added every 2 bits, and the upper bit of the 2-bit data is“ H ”and the lower bit is It is marked with “L”.

  Then, the write transmission control unit 653 reads out the dot formation data SI for each unit determined by the output buffer 652 and transmits it to the head HD. In the example of FIG. 6A, the write transmission control unit 653 reads the N upper bits H in the first column in order from the leading end side in the nozzle column direction from the output buffer 652 and transmits them to the head HD (SI (H, 1)). , SI (H, 2)... SI (H, N)). That is, the write transmission control unit 653 reads N pieces of data from the output buffer 652 and transmits them to the head HD. Next, the write transmission control unit 653 transmits and transmits N lower bits L in the first column to the head HD in order from the front end side in the nozzle column direction (SI (L, 1), SI (L, 2). ) ... SI (L, N)).

  When the data in the first column is thus transmitted, the write transmission control unit 653 transmits N upper bits H or lower bits L for each column, and finally N lower bits L in the eighth column. Transmit up to. That is, the unit data amount of the dot formation data SI transmitted from the write transmission control unit 653 to the head HD is “N”.

  The N pieces of data (SI (1) to SI (N)) arranged for each column are dot formation data SI corresponding to pixels having the same position in the cross direction on the medium. Here, among the data stored in the output buffer 652, N dot formation data (SI (1) to SI (N)) in the same row (for example, the first row) are assigned to the nozzles belonging to the same nozzle row. Ink ejection at the same timing is controlled by the dot formation data SI (1) to SI (N). That is, since the unit data amount of the dot formation data SI transmitted from the write transmission control unit 653 to the head unit 40 is “N”, the number of nozzles that can control ink ejection by one write transmission control unit 653 Can be said to be “N”.

  6B is a diagram illustrating data transmitted from the data transmission unit 651 having a unit data amount N of 180, and FIG. 6C illustrates data transmitted from the data transmission unit 651 having a unit data amount N of 360. FIG. The unit data amount N of the data transmission unit 651 varies depending on the model of the printer 1, that is, the type of the controller 60. Some printers 1 transmit the dot formation data SI to the dummy nozzles, while other printers 1 do not transmit the dot formation data SI.

  As shown in FIG. 6B, if the unit data amount N is 180 and the controller 60 does not transmit data to the dummy nozzles, first, the upper bits (SI ( After H, 1) to SI (H, 180)) are transmitted to the head unit 40, lower bits (SI (L, 1) to SI (L, 180)) for 180 nozzles are transmitted to the head unit 40. The Therefore, in order to transmit data for one nozzle row (360), two signal lines are required. The predetermined transmission period T is a period for transmitting data for ejecting ink droplets from the nozzles simultaneously at a certain timing.

  On the other hand, as shown in FIG. 6C, if the unit data amount is 360 and the controller 60 does not transmit data to the dummy nozzles, first, the upper bits (SI for 360 nozzles) are transmitted during a predetermined transmission period T. After (H, 1) to SI (H, 360)) are transmitted to the head unit 40, lower bits (SI (L, 1) to SI (L, 360)) for 360 nozzles are transmitted to the head unit 40. Is done. Therefore, one signal line is sufficient to transmit data for one nozzle row. However, in FIG. 6C, compared with FIG. 6B, since the data amount twice as large as the predetermined transmission period T is transmitted to the head unit 40, the transmission time of 1-bit data (for example, SI (H, 1)) is shortened.

  Thus, the unit data amount N transmitted from the data transmission unit 651 to the head unit 40 differs according to the storage capacity of the output buffer 652 of the controller 60, and the number of signal lines for transmitting data and the transmission time of 1-bit data are different. Come different.

<Print data transmission method>
FIG. 7A to FIG. 7C are diagrams showing differences in print data transmission methods from the controller 60 to the head unit 40. The type of controller 60 differs depending on the model of the printer 1, and the type of controller 60 is often different in the transmission method of print data to the head unit 40. Here, the embodiment will be described by taking three types of transmission methods as examples. Further, the transmission method shown below is a transmission method related to dot formation data SI and clock signal SCLK (corresponding to data for ejecting fluid from the head) in the print data.

  FIG. 7A is a diagram for explaining the first transmission method. In the controller 60 using the first transmission method, it is assumed that the unit data amount of the data transmission unit 651 is 180 pieces as shown in FIG. 6B and the dot formation data SI of the dummy nozzle is not transmitted. That is, in the first transmission method, data for 180 nozzles is transmitted within the transmission cycle T, and the frequency of the clock signal SCLK at this time is set to “first frequency f1 (Hz)”.

  Therefore, in the first transmission method, two signal lines are required to transmit the dot formation data SI for one nozzle row (for 360 nozzles). Further, it is assumed that the head HD is provided with four nozzle rows shown in FIG. 3B. For example, it is assumed that a yellow nozzle row Y for ejecting yellow ink, a magenta nozzle row for ejecting magenta ink, a nozzle row C for ejecting cyan ink, and a nozzle row K for ejecting black ink K are provided. Therefore, eight signal lines (= 2 × 4) are required to transmit the dot formation data SI from the controller 60 to the head unit 40.

  In the dot formation data signal SI transmitted by the first transmission method, when the potential indicated by the dot formation data signal SI is “3.3 V”, the data level of the dot formation data SI is set to “1 = H level”. When the potential indicated by the dot formation data signal SI is “0 V (GND / ground)”, the data level of the dot formation data SI is set to “0 = L level”. That is, the dot formation data signal SI (and the clock signal SCLK) transmitted to the head unit 40 by the first transmission method is a signal with a 3.3 V amplitude based on GND, as shown in FIG. 7A.

  The data level HL of the dot formation data SI is determined based on the potential of the dot formation data signal SI at the rising timing or falling timing of the pulse generated by the clock signal SCLK. For example, the dot formation data signal SI in FIG. 7A is a signal related to the dot formation data SI of the black nozzle row K. Since the potential of the dot formation data signal SI at the rising timing of the first pulse of the clock signal SCLK is 3.3 V, the upper bits SI (H, K1) of the pixels assigned to the tip nozzles of the black nozzle row K are “ 1 (H level) ”. Similarly, since the potential of the dot formation data signal SI at the falling timing of the first pulse of the clock signal SCLK is 0 V, the upper bits SI (H, H) of the pixels assigned to the second nozzle from the tip of the black nozzle row K It can be determined that K2) is “0 (L level)”.

  FIG. 7B is a diagram for explaining the second transmission method. In the controller 60 using the second transmission method, as shown in FIG. 6C, the unit data amount of the data transmission unit 651 is 360, and the dot formation data SI of the dummy nozzle is not transmitted. That is, in the second transmission method, the dot formation data SI for 360 nozzles is transmitted within the transmission period T, and the frequency of the clock signal SCLK at this time is set to “second frequency f2 (Hz)”. In the second transmission method, the number of dot formation data SI transmitted within the transmission cycle T is larger than that in the first transmission method, and the number of pulses generated in the clock signal SCLK is also increased. The frequency becomes higher than the first frequency f1.

  In the second transmission method, since the dot formation data SI for one nozzle row is transmitted through one signal line, four signal lines are required to transmit the dot formation data SI from the controller 60 to the head unit 40. Become. For this reason, the number of signal lines can be reduced in the second transmission method compared to the first transmission method.

  However, since the second transmission method transmits twice the amount of data to the head head unit 40 within the transmission period T compared to the first transmission method, the transmission time of 1-bit data is shortened. For this reason, if the dot formation data signal SI of the second transmission method is a signal with a 3.3 V amplitude based on GND as in the first transmission method, the potential change cannot follow in a short transmission period of 1-bit data. This will cause noise generation and waveform distortion. In particular, when the dot formation data signal SI is transmitted from the controller 60 to the head unit 40 via the flexible cable FC, the dot formation data signal SI becomes a noise generation source and affects other devices in the printer 1. .

  Therefore, in the second transmission method, the amplitude of the dot formation data signal SI is set to, for example, “1.6 V” smaller than in the first transmission method. If the amplitude is small, even if the transmission time of 1-bit data is short, the potential change can be followed, the generation of noise can be suppressed, and the influence of external noise can be reduced (EMI countermeasures). In other words, in the first transmission method, since the number of dot formation data transmitted in the transmission period T is small and the transmission time of 1-bit data can be secured long, the amplitude of the dot formation data signal SI is as large as 3.3V. I can do it.

  In addition, in the dot formation data signal SI (and clock signal SCLK) transmitted by the first transmission method, a pulse having a 3.3 V amplitude is generated with reference to GND (0 V), whereas the second transmission is performed. In the dot formation data signal SI transmitted by the method, a pulse with 1.6 V amplitude is generated with 1.7 V as a reference. Thus, by generating a pulse based on a potential higher than GND, the generation of noise can be suppressed and the influence of external noise can be reduced. Therefore, in the dot formation data signal SI transmitted by the second transmission method, when the potential indicated by the dot formation data signal SI is “3.3 V”, the data level of the dot formation data SI is set to “1 = H level”. When the potential indicated by the dot formation data signal SI is “1.7 V”, the data level of the dot formation data SI is set to “0 = L level”.

  FIG. 7C is a diagram for explaining the third transmission method. In the controller 60 using the third transmission method, dot formation data SI (excluding dummy nozzles) for two nozzle rows is transmitted within the transmission cycle T. In the dot formation data signal SI of FIG. 7C, the dot formation data (for example, SI (H, K1)) of the black nozzle row K and the dot formation data (for example, SI (H, CI)) of the cyan nozzle row are alternately transmitted. . The frequency of the clock signal SCLK at this time is “third frequency f3 (Hz)”. The third frequency f3 is higher than the first frequency f1 and the second frequency f2.

  In the third transmission method, since the number of dot formation data SI transmitted within the transmission period T is large, the amplitude of the dot formation data signal SI is reduced to “1.6 V” as in the second transmission method. By doing so, it is possible to suppress the generation of noise and reduce the influence of external noise (EMI countermeasures).

  In the third transmission method, the dot formation data SI is transmitted by “differential transmission”. In differential transmission, as shown in FIG. 7C, a signal having a reverse phase (non-inverted signal / inverted signal) is transmitted. By performing differential transmission, it is possible to cancel noise generated in common between the non-inverted signal and the inverted signal in later processing, and to acquire data from which the influence of noise has been removed. The first transmission method and the second transmission method are so-called single-ended transmissions in which only non-inverted signals are transmitted. Compared to single-ended transmission, differential transmission can cancel common noise and transmit a large number of data during the transmission period. However, differential transmission requires twice as many signal lines as single-ended transmission. Therefore, in the third transmission method, the dot formation data SI for two nozzle rows is transmitted within the transmission period T. However, since the signal lines for the non-inverted signal and the inverted signal are required, the dot is transferred from the controller 60 to the head unit 40. Four signal lines are required to transmit the formation data SI.

  Further, in the non-inverted dot formation data signal SI transmitted by the third transmission method, when the potential indicated by the non-inverted dot formation data signal SI is “1.6 V”, the data level of the dot formation data SI is “ When the potential indicated by the non-inverted dot formation data signal SI is “0 V (GND)”, the data level of the dot formation data SI is “0 = L level”. In FIG. 7C, only the non-inverted signal is shown as the clock signal SCLK for the sake of simplicity, but the clock signal SCLK is also differentially transmitted.

  In summary, the first transmission method is high-amplitude (3.3V) single-ended transmission, and the second transmission method is low-amplitude (1.6V) single-ended transmission in which the L-level potential is level-shifted from GND. The third transmission method is low-amplitude (1.6 V) differential transmission (LVDS). The transmission method (FIGS. 7A to 7C) of the dot formation data signal SI and the clock signal SCLK from the controller 60 differs depending on the printer model, that is, the type of the controller 60. Then, the processing (described later) on the head unit 40 side that receives the dot formation data signal SI and the clock signal SCLK also differs.

  If a dedicated head unit 40 is manufactured for each type of controller 60 (for each model of the printer 1), a printer manufacturer that manufactures various types of printers must manufacture a large number of dedicated head head units 40. In other words, the manufacturing cost is increased. Therefore, the present embodiment aims to generalize the head unit 40.

=== Reception Signal Processing in the Head Unit 40 ===
FIG. 8A is a diagram illustrating a process flow after the head unit 40 receives the dot formation data signal SI and the clock signal SCLK transmitted from the controller 60. As shown in FIG. 7, the transmission method of the dot formation data signal SI and the clock signal SCLK differs depending on the type of the controller 60. When the transmission methods are different, the shapes of the dot formation data signal SI and the clock signal SCLK received by the head unit 40 are different as shown in FIG. 8A.

  Specifically, the dot formation data signal SI and the clock signal SCLK (hereinafter, the first reception signals SI (1) · SCLK (1)) transmitted by the first transmission method (FIG. 7A) have an L level potential of GND. This is a signal of 3.3V amplitude. The dot formation data signal SI and the clock signal SCLK (hereinafter referred to as the second reception signal SI (2) · SCLK (2)) transmitted by the second transmission method (FIG. 7B) are L-level potential shifted with respect to GND. 1.6V amplitude signal. The dot formation data signal SI and the clock signal SCLK (hereinafter, the third reception signals SI (3) · SCLK (3)) transmitted by the third transmission method (FIG. 7C) are 1.6 V whose L level potential is GND. It is an antiphase signal of amplitude (non-inverted signal / inverted signal).

  As described above, the signal SI · SCLK received by the head unit 40 from the controller 60 differs in amplitude depending on the type of the controller 60, the L level potential is level-shifted from GND, or two signals having opposite phases. Therefore, it is difficult to cause the shift register group 442 (FIG. 4) to determine the data level HL of the dot formation data SI using the received signal SI · SCLK as it is.

  Therefore, the data processor 446 in the control logic 441 processes the received signal SICK · SCLK and converts it into an output signal SI ′ / SCLK ′ having the same shape. Here, the received signal SI · SCLK is converted into an output signal SI ′ · SCLK ′ having an amplitude of 3.3 V and having an L level potential of GND. In other words, 3.3V (corresponding to the first potential) is output when the received signal SI · SCLK is at the H level, and 0V (corresponding to the second potential) is output when the level of the received signal SI · SCLK is at the L level. The signal SI ′ · SCLK ′ (corresponding to output data) is converted. By doing so, the shift register group 442 can easily determine the data level HL of the dot formation data SI. For example, as shown in FIG. 5, when the output signal SI ′ · SCLK ′ is input to the shift registers 442a and 442b, the shift registers 442a and 442b form dots at the rising or falling timing of the clock signal SCLK ′. Based on the potential (3.3 V or 0 V) of the data signal SI ′, the data level HL of the dot formation data SI is determined.

  In addition, the received signal SI · SCLK transmitted from the controller 60 may generate noise or have a distorted waveform during a long transmission path (in a period of passing through the FC). For this reason, there is a possibility that the shift register group 442 erroneously determines the data level HL of the dot formation data SI with respect to the reception signals SI and SCLK in which noise is generated or lost. Therefore, the shift signal group 442 converts the received signal SI · SCLK into the output signal SI ′ · SCLK ′ in the data processing unit 446 so that the shift register group 442 can generate dot formation data based on the output signal in which noise generation and waveform rounding are suppressed. The data level HL of SI can be accurately determined. That is, the data processing unit 446 plays a role of shaping the received signal SI · SCLK into a clean waveform.

  The processing (described later) for converting the received signal SI · SCLK into the output signal SI ′ / SCLK ′ by the data processing unit 446 differs depending on the type of the received signal SI · SCLK. That is, the processing in the data processing unit 446 differs depending on the reception signals SI (1) to (3) · SCLK (1) to SCLK (3) transmitted to the head unit 40 by different transmission methods. Therefore, in order to generalize the head unit 40, the received signal SI · SCLK is converted into the output signal SI ′ · SCLK ′ according to the type of the received signal SI · SCLK according to each transmission method (FIG. 7). It is necessary to provide a data processing unit.

  FIG. 8B is a control signal table showing control signals DSW (1) · DSW (2) corresponding to the frequency of the clock signal SCLK, and FIG. 9 converts the received signals SI · SCLK into output signals SI ′ · SCLK ′. It is a figure explaining the data processing part 446 to perform. The table in FIG. 8A is a control signal table in which the frequency of the clock signal SCLK received from the controller 60 is associated with the control signal DSW, and the control signal table is stored in the memory IC 45 in the head unit 40. In the head unit 40, the first reception signal SI (1) / SCLK (1) according to the first transmission method is processed by the first data processing unit 70, and the second reception signal SI (2) according to the second transmission method is processed. SCLK (2) and the third reception signal SI (3) and SCLK (3) by the third transmission method are processed by the common second third data processing unit 71. Therefore, it is necessary to change the data processing units 70 and 71 that process the reception signals SI and SCLK according to the types of the reception signals SI and SCLK.

  By the way, the received signals SI and SCLK transmitted by the three transmission methods shown in FIG. Therefore, the head unit 40 of the present embodiment inputs the received signal SI · SCLK to the first data processing unit 70 based on the frequency of the clock signal SCLK received from the controller 60, or the second third data Whether to input to the processing unit 71 is determined. For this purpose, the frequency analysis unit 451 is provided in the memory IC 45 (FIG. 8A) of the head unit 40, and the clock signal SCLK received from the controller 60 is also input to the memory IC 45. When the head unit 40 receives data from the controller 60, the head unit 40 causes the frequency analysis unit 451 to analyze the frequency of the clock signal SCLK. Then, the memory IC 45 determines the control signal DSW based on the frequency and the control signal table (FIG. 8B) and outputs the control signal DSW to the control logic 441. Not only the frequency of the clock signal SCLK is analyzed, but also the frequency of the dot formation data signal SI may be analyzed to determine the control signal DSW.

  In the control signal table (FIG. 8B), two control signals DSW (1) and DSW (2) are associated with the frequencies f1 to f3 of the clock signal SCLK in each transmission method. One first control signal DSW (1) is used to determine whether the received signal SI · SCLK is input to the first data processing unit 70 shown in FIG. 9 or the second data processing unit 71. Control signal. The other second control signal DSW (2) is a control signal for controlling the operation in the second third data processing unit 71 (described later).

  According to the control signal table of FIG. 8B, the first control signal DSW (1) is set to “1 (= H level)” with respect to the frequency f1 of the clock signal SCLK (1) according to the first transmission method. The first control signal DSW (1) is set to “0 (= L level)” with respect to the frequency f2 of the clock signal SCLK (2) according to the second transmission method and the frequency f3 of the clock signal SCLK (3) according to the third transmission method. Has been.

  In the data processing unit 446 (FIG. 9), the received signals SI and SCLK from the controller 60 are processed by the first data processing unit 70 or the second third data processing in accordance with the first control signal DSW (1) from the memory IC 45. Input to any of the units 71. Transmission gates 72 (1) to 72 (3) are provided on the output sides of the first data processing unit 70 and the second third data processing unit 71, respectively. The first control signal DSW (1) is also input to the transmission gate 72. In the present embodiment, a data processing unit 446 that processes the dot formation data signal SI and a data processing unit 446 that processes the clock signal SCLK are provided, and the same processing is performed on both the dot formation data signal SI and the clock signal SCLK. . In the following, for the sake of simplicity, the processing of the dot formation data signal SI will be described on behalf of two received signals.

  If the first control signal DSW (1) is “1 (H level)”, the data processing unit 446 inputs the dot formation data signal SI to the M input unit shown in FIG. When the first control signal DSW (1) is “1”, the transmission gate 72 (1) on the output side of the first data processing unit 70 is turned on, and the signal output from the first data processing unit 70 is Let it pass. On the other hand, the transmission gates 72 (2) and 72 (3) on the output side of the second third data processing unit 71 are turned off, and the second third data processing unit 71 is set not to operate.

  On the other hand, if the first control signal DSW (1) is “0 (L level)”, the data processing unit 446 inputs signals to the M input unit and the P input unit (details will be described later). When the first control signal DSW (1) is “0”, the transmission gate 72 (1) on the output side of the first data processing unit 70 is turned off, and the first data processing unit 70 is set not to operate. Has been. On the other hand, the transmission gates 72 (2) and 72 (3) on the output side of the second third data processing unit 71 are turned on, and the signal output from the second third data processing unit 71 is allowed to pass.

  Two transmission gates 72 (2) and 73 (3) are provided on the output side of the second and third data processing unit 71. This is because the dot formation data signal SI for each nozzle row is transmitted from the second third data processing unit 71 when the dot formation data SI for two nozzle rows is transmitted with the same signal as in the third transmission method of FIG. 7C. This is because the data is output separately. That is, the dot formation data signal SI output from one transmission gate 72 (2) is output to the shift register group 442 corresponding to the nozzle row X, and the dot formation data signal output from the other transmission gate 72 (3). SI is output to the shift register group 442 corresponding to the nozzle row Y.

  As described above, in the head unit 40 of the present embodiment, the received signal SI · SCLK is converted into the first data processing unit according to the frequency of the clock signal SCLK received from the controller 60 (in response to the first control signal DSW (1)). It is possible to switch between processing at 70 and processing at the second and third data processing unit 71. By doing so, even if the shape of the received signal SI · SCLK from the controller 60 is different for each type of controller 60 (for each model of the printer 1) and the processing of the received signal SI · SCLK in the head unit 40 is different, the head unit 40 generalizations can be realized.

Further, by determining to which of the first data processing unit 70 and the second third data processing unit 71 the reception signal SI · SCLK is input according to the frequency of the reception signal (clock signal SCLK), for example, a printer The work of associating the controller 60 with the head unit 40 during the manufacturing process or replacement of the head unit 40 can be reduced. Specifically, after attaching the general-purpose head unit 40 to the main body of the printer 1 in which the controller 60 is incorporated, the head unit 40 converts the received signal SI to which data processing unit 70. It is not necessary to specify whether the processing is performed at 71. For example, it is not necessary to store a control signal (DSW (1) in this case) for determining the processing method of the received signal SI · SCLK in the memory IC 45 of the head unit 40 or the like. That is, in the head unit 40 of the present embodiment, the first control signal DSW (1) is determined according to the frequency of the reception signal (clock signal SCLK), and the reception signal SI is determined according to the first control signal DSW (1). -The SCLK processing method is automatically switched.
Hereinafter, the processing method in each data processing part 70 and 71 of received signal SI * SCLK by each transmission system is demonstrated.

<Processing of First Received Signal SI (1)>
FIG. 10 is a diagram for explaining a method of processing the first reception signals SI (1) · SCLK (1). The first reception signal SI (1) transmitted by the first transmission method of FIG. 7A (hereinafter, the clock signal SCLK (1) is omitted) is a signal having an amplitude of 3.3 V with the L level potential being GND as shown in the figure. It is. In the received signal SI (1) transmitted from the controller 60 to the head unit 40, noise is generated or the waveform is distorted. Therefore, the first data processing unit 70 prepares the waveform. By doing so, the shift register group 442 can accurately determine the data level HL of the dot formation data SI.

  As shown in FIG. 9 described above, the memory IC 45 causes the data processing unit 446 to send the first control signal DSW (1) = [1 according to the frequency f1 (corresponding to the first frequency) of the clock signal SCLK (1). ] Is output, the data processing unit 446 inputs the first received signal SI (1) to the M input unit of the first data processing unit 70. The first control signal DSW (1) is also input to the transmission gate 72, the first data processing unit 70 operates, and the second third data processing unit 71 does not operate.

  The first data processing unit 70 is a comparison circuit (for example, a Schmitt trigger circuit). In the first data processing unit 70 of FIG. 10, a signal from the M input unit is input to the CMOS via the resistor R. The CMOS is a circuit in which a P-channel transistor Pt and an N-channel transistor Nt are connected. When the signal input to the CMOS is at the H level, the N-channel transistor Nt is turned on, and the GND potential is output in FIG. On the other hand, when the signal input to the CMOS is at L level, the P-channel transistor Pt is turned on, and 3.3V is output in FIG.

  In the first data processing unit 70, when the potential indicated by the reception signal SI (1) is 35% (about 1.2V) or more of the 3.3V amplitude from GND (t0 to t1), the output signal SI ′ When the potential of (1) becomes “3.3V” and the potential indicated by the received signal SI (1) is less than 35% of the 3.3V amplitude from GND, the potential of the output signal SI ′ becomes “0V”. Is set to That is, in the first data processing unit 70, if the potential of 35% of the amplitude of 3.3V from GND is set as the reference potential (corresponding to the first reference potential), and the potential of the reception signal SI (1) is equal to or higher than the reference potential, If the potential of the H level (3.3 V) is output and the potential of the reception signal SI (1) is less than the reference potential, the L level potential (0 V) is output. As a result, according to the data level of the reception signal SI (1), the first data processing unit 70 outputs a 3.3V amplitude signal whose L level potential is GND as the output signal SI ′ (1). .

  Thus, by processing the received signal SI (1) in the first data processing unit 70, noise and waveform rounding of the received signal SI (1) from the controller 60 can be removed, and the shift register group 442 Can accurately determine the data level HL of the dot formation data SI based on the output signal SI (1) which is neatly shaped.

  The CMOS in the first data processing unit 70 outputs 3.3V when the input signal is at L level, outputs 0V when the input signal is at H level, and the data level of the dot formation data signal SI (1). Therefore, the inversion unit 73 is provided on the output side of the CMOS. Further, the reference potential for determining the data level HL of the first reception signal SI (1) is not limited to the 35% potential point (1.2V) of the 3.3V amplitude from the GND, for example, the potential point of 50% of the amplitude. But you can.

<Processing of Second Received Signal SI (2)>
FIG. 11A is a diagram for explaining a processing method of the second received signal SI (2) (hereinafter, SCLK (2) is omitted), and FIG. 11B is a potential Vm input to the M input unit (corresponding to the first input unit). (Reception signal SI (2)) and a potential Vp (constant potential) input to the P input unit (corresponding to the second input unit). FIG. 11C shows that the first control signal is at the H level (1). It is a figure which shows the motion of the differential circuit 74 at the time. The second received signal SI (2) transmitted by the second transmission method of FIG. 7B is a 1.6V amplitude signal in which the potential is shifted by 1.7V with respect to GND as shown in FIG. 11A. The received signal SI (2) is converted by the second third data processing unit 71 into an output signal SI ′ (2) having an amplitude of 3.3 V having an L level potential of GND.

  The second and third data processing unit 71 includes a differential circuit 74, a CMOS, and an inverting unit 73. The differential circuit 74 includes P-channel transistors Pt (1) (2) that are arranged in the same manner as the N-channel transistors Nt (1) (2) that are symmetrically arranged. The base portion of one N-channel transistor Nt (1) is the M input portion, and the base portion of the other N-channel transistor Nt (2) is the P input portion. A junction portion between the P channel transistor Pt and the N channel transistor Nt (2) on one side is an output portion. The signal output from the differential circuit 74 is input to the CMOS. Further, in the differential circuit 74 of FIG. 10, the N-channel transistor Nt (1) (2) arranged symmetrically is connected to GND (or a constant potential VSS) via another N-channel transistor Nt (3). ing.

  As described above (FIG. 9), the memory IC 45 sends the first control signal DSW (1) = [0] to the data processing unit 446 according to the frequency f2 (corresponding to the second frequency) of the clock signal SCLK (2). When output, the data processing unit 446 processes the second received signal SI (2) in the second and third data processing unit 71. Further, the memory IC 45 generates a second control signal DSW (2) for distinguishing between the second reception signal SI (2) and the third reception signal SI (3) according to the frequency f2 of the clock signal SCLK (2). Then, referring to the control signal table (FIG. 8B), the data is output to the data processing unit 446. According to the control signal table of FIG. 8B, the second control signal DSW (2) corresponding to the frequency f2 of the clock signal SCLK (2) of the second transmission method is set to “1 (H level)”, and the third The second control signal DSW (2) corresponding to the frequency f3 of the clock signal SCLK (3) of the transmission method is set to “0 (L level)”.

  When the second control signal DSW (2) is “1”, the data processing unit 446 inputs the second received signal SI (2) to the M input unit of the differential circuit 74 of the second third data processing unit 71. A constant potential is input to the P input portion of the differential circuit 74. Here, the constant potential input to the P input unit is set to 2.5V. The potential Vp input to the P input unit corresponds to the central potential of the amplitude of the second reception signal SI (2) input to the M input unit, as shown in FIG. 11B.

  In the second third data processing unit 71, the difference potential “Vm− between the potential Vm of the second reception signal SI (2) input to the M input unit and the constant potential Vp = 2.5V input to the P input unit. If the potential based on “Vp” (corresponding to the potential based on the difference) is equal to or higher than the reference potential (corresponding to the second reference potential), an H level potential (3.3 V) is output, and the difference potential “Vm−Vp” is output. If the potential based on it is less than the reference potential, an L level potential (0 V) is output.

  Specifically, from the output part of the differential circuit 74, the potential Vm of the second received signal SI (2) input to the M input part and the constant potential Vp (= 2.5V) input to the P input part. A potential ((Vm−Vp) α in the figure) based on the differential potential is output. In the differential circuit 74 shown in FIG. 11A, the symmetrically arranged P-channel transistors in the upper stage function as a current mirror circuit to amplify the current, so that the differential potential “Vm−Vp” is supplied from the output section from the differential circuit 74 as power. The amplified signal is output. Then, the potential (Vm−Vp) α output from the differential circuit 74 is input to the CMOS, and is turned on / off based on the threshold potential (similar to the first data processing unit 70). As a result, the second reception signal SI (2) is output as an output signal SI '(2), which is a 3.3 V amplitude signal whose L level potential is GND.

  Thus, the low amplitude (1.6 V) received signal SI (2) in which the L level potential is shifted from GND is changed to the 3.3 V amplitude output signal SI ′ (2) in which the L level potential is GND. Can be converted. As a result, the shift register group 442 can determine the data level HL of the dot formation data SI. Further, since noise and waveform rounding are removed from the output signal SI ', the shift register group 442 can accurately determine the data level HL of the dot formation data SI.

  As shown in FIG. 11C, the first control signal DSW (1) is input to the differential circuit 74 of the present embodiment. When the head unit 40 receives the first reception signal SI (1) and processes it by the first data processing unit 70, the first control signal DSW (1) becomes “1 (H level)”. At this time, the first control signal “1 (H level)” is applied to the N-channel transistor Nt (3) between the junction of the N-channel transistors Nt (1) Nt (2) in the symmetrical arrangement of the differential circuit 74 and GND. By being input, the N-channel transistor Nt (3) is turned on, and the input signals of the M input unit and the P input unit flow to GND (or settle to the predetermined potential VSS). Thus, when the first control signal DSW (1) is “1”, the differential circuit 74 is set not to operate.

  That is, it is possible to prevent the first received signal SI (1) from being processed by the second third data processing unit 71. In this way, the signal SI received by the head unit 40 can be processed by the processing format (data processing units 70 and 71) corresponding to the transmission method. Further, as described with reference to FIG. 9, the first control signal DSW (1) is also input to the transmission gate 72 provided on the output side of each data processing unit 70 and 71, and either one operates. It is set so that the correct data processing units 70 and 71 are used according to the type of the received signal SI.

<Processing of Third Received Signal SI (3)>
FIG. 12A is a diagram for explaining a processing method of the third reception signal SI (3) (hereinafter, the clock signal SI (3) is omitted), and FIG. 12B determines the data level of the reception signal SI (3). It is a figure which shows the reference potential Vx at the time. The third reception signal SI (3) transmitted by the third transmission method in FIG. 7C is a 1.6 V amplitude signal whose L level potential is GND, and two signals having opposite phases (a non-inverted signal and an inverted signal). ). The received signal SI (3) is converted by the second third data processing unit 71 into a non-inverted output signal SI ′ (3) having an amplitude of 3.3 V and an L level potential of GND. First, the memory IC 45 outputs the first control signal DSW (1) = [0] to the data processing unit 446 in accordance with the frequency f3 (corresponding to the third frequency) of the clock signal SCLK (3) from the controller 60, and the data The processing unit 446 processes the third received signal SI (3) in the second third data processing unit 71.

  The memory IC 45 also outputs the second control signal DSW (2) = [0] to the data processing unit 446 according to the frequency f3 of the clock signal SCLK (3). Then, the data processing unit 446 inputs the non-inverted reception signal SI (3) to the M input unit of the differential circuit 74 of the second and third data processing unit 71 as shown in FIG. An inverted reception signal SI (3) is input to the P input unit. In the second and third data processing unit 71, as shown in FIG. 12B, the non-inverted signal potential Vm (solid line) input to the M input unit and the inverted signal potential Vp (dotted line) input to the P input unit. If the difference potential “Vm−Vp” is equal to or higher than the threshold Vx, an H level potential (3.3 V) is output. If the difference potential “Vm−Vp” is less than the threshold Vx, the L level potential (0 V) is output. It is set to output.

  Specifically, when the non-inverted received signal SI (3) is input to the M input unit and the inverted received signal SI (3) is input to the P input unit, the second received signal SI (2) is processed. Similarly, a potential based on the difference (Vm−Vp) between the potential Vm of the non-inverted received signal SI (3) and the potential Vp of the inverted received signal SI (3) from the differential circuit 74 ((Vm−Vp) α in the figure). ) Is output. A potential based on the potential difference (Vm−Vp) between the non-inverted signal and the inverted signal is input to the CMOS, and on / off control is performed based on the reference potential (corresponding to the third reference potential).

  As a result, the low-level (1.6 V) reverse-phase received signal SI (3) transmitted from the controller 60 has an L-level potential of 3 according to the data level HL of the received signal SI (3). .3V amplitude output signal SI ′ (3). By doing so, the shift register group 442 can determine the data level HL of the dot formation data SI '. Also, as shown in FIG. 12B, a potential based on the difference between the non-inverted signal potential Vm and the inverted signal potential Vp is output from the differential circuit 74, and noise generated in common between the non-inverted signal and the inverted signal at that time Is offset. That is, the signal output from the differential circuit 74 is suitable for transmitting a large number of dot formation data SI since noise is removed. In the third transmission method, since the dot formation data SI for two nozzle rows (black nozzle row K and cyan nozzle row C in FIG. 7C) is transmitted by the same signal, the second third data processing unit 71 The operation of dividing the dot formation data SI for two nozzle rows into the dot formation data SI for each nozzle row (not shown).

<About the common processing of the second received signal and the third received signal>
FIG. 13 is a diagram for explaining a method of switching between the second received signal SI (2) and the third received signal SI (3). In the head unit 40 of the present embodiment, the second reception signal SI (2) (a reception signal having a 1.6V amplitude level shifted from GND) and the third reception signal SI (3) (the L level potential is GND 1) .6V amplitude antiphase signal) is processed by the same second third data processing unit 71 (differential circuit 74). On the other hand, the first reception signal SI (1) (a signal having an amplitude of 3.3 V whose L level potential is GND) is processed by the first data processing unit 70 (comparison circuit).

  That is, the first received signal SI (1) and the second received signal SI (2) transmitted by single end are processed by different data processing units 70 and 71, and the second received signal SI (2) transmitted by single end is transmitted. The third received signal SI (3) differentially transmitted is processed by the same second third data processing unit 71.

  This is because the second received signal SI (2) has a smaller amplitude than the first received signal SI (1), and the L level potential is shifted from GND for EMI countermeasures. This is because SI (2) cannot be processed by the first data processing unit 70. Specifically, as shown in FIG. 10, in the first data processing unit 70, the reception signal SI (1) input to the M input unit is set to a 35% point (about 1.2V) with a 3.3V amplitude from GND. ) Is used as a reference to determine the data level HL. For this reason, in the second reception signal SI (2), the L level potential is level-shifted from GND to 1.7 V (corresponding to a predetermined potential), and therefore all are determined to be H level. Therefore, the second received signal SI (2) cannot be processed by the first data processing unit 70.

  Therefore, the second received signal SI (2) of single end transmission whose L level potential is level shifted from GND is processed using the second third data processing unit 71, that is, the differential circuit 74. The potential ((Vm−Vp) α) based on the difference between the potential (Vm) of the second received signal SI (2) and the intermediate potential (2.5V = Vp) of the amplitude of the second received signal SI (2). 2 Determine the data level HL of the received signal SI (2). Therefore, when processing the second received signal SI (2), the second received signal SI (2) is input to the M input portion of the differential circuit 74, and a constant potential is applied to the P input portion of the differential circuit 74. Input (2.5V). By doing so, the differential circuit 74 can determine the data level HL of the second reception signal SI (2) of the single end transmission in which the L-level potential is level-shifted.

  As shown in FIG. 13, when the second received signal SI (2) is processed, a constant potential (2.5V) from the power supply VDD (3.3V) through the resistor R is input to the P input unit. The When the second received signal SI (2) is processed (DSW (2) = 1), a constant potential (2.5V) is input to the P input unit, and the third received signal SI (3) is processed. In this case (DSW (2) = 0), the switch 75 is switched based on the second control signal DSW (2) so that the inverted reception signal SI (3) is input to the P input unit.

  In this way, by processing the received signal SI (2) level-shifted by single-ended transmission and the received signal SI (3) differentially transmitted by the same differential circuit 74, the circuit configuration can be simplified. And cost can be reduced. If a comparison circuit for comparing with a reference potential corresponding to the amplitude of the second reception signal SI (2) is provided separately, the circuit configuration becomes complicated. Further, by changing a constant potential (2.5 V in this case) input to the P input portion of the differential circuit 74 by changing the constant of the resistor R or the like, the level shift from GND is different in level shift amount and amplitude. Signal processing can be performed. Therefore, it is possible to process received signals SI from more types of controllers 60. In other words, the head unit 40 of this embodiment can be incorporated into various printers 1 by changing the constant potential (can be associated with the controller 60).

<Modification>
FIG. 14 is a diagram illustrating a modification of the second third data processing unit 71. 11 and 12 use the differential circuit 74 in which transistors having uniform characteristics are combined in contrast, but this is not restrictive. For example, an operational amplifier 76 may be used as the differential circuit as shown in FIG. Also in this case, when the second control signal DSW (2) is “0”, the non-inverted reception signal SI (3) is input to the plus (+) input terminal of the operational amplifier 76, and the minus (−) input terminal. The inverted reception signal SI (3) is input to. On the other hand, when the second control signal DSW (2) is “1”, the second received signal SI (2) is input to the plus (+) input terminal of the operational amplifier 76, and a constant potential (−) is applied to the minus (−) input terminal. 2.5V) may be input.

<Summary>
In summary, the head unit 40 of this embodiment can perform processing according to the type of the received signal SI · SCLK even if the transmission method from the controller 60 is different. Therefore, it is not necessary to design a dedicated head unit 60 for each type of controller 60 (for each model of the printer 1), and generalization of the head unit 40 can be realized.
Furthermore, the head unit 40 of the present embodiment can analyze the frequency of the received signal SCLK and automatically switch to data processing suitable for each transmission method according to the frequency. Therefore, it is not necessary to associate the controller 60 with the head unit 40 (for example, an operation for storing a control signal in the memory IC) in the manufacturing process, and the manufacturing process can be facilitated.
In the head unit 40 of the present embodiment, a signal whose L level potential is level-shifted from GND or whose amplitude is small, such as the second received signal SI (2), is input to one side of the differential circuit 74. Then, a constant potential is input to the other input portion of the differential circuit 74. By doing so, the level-shifted received signal having a small amplitude can be processed by the differential circuit, and the circuit configuration can be simplified.

=== About Movement of Shift Register Group According to Frequency ===
FIG. 15 shows a control signal table related to the third control signal DSW (3) that defines the processing of the shift register group 442 stored in the memory IC 45, and FIGS. 16A and 16B show shifts due to the difference in the number of data of the received signal SI. FIG. 10 is a diagram illustrating a difference in operation of a register group 442. So far, an embodiment has been described in which the process of converting the received signal SI into the output signal SI ′ is changed according to the difference in frequency of the received signal SI. However, the present invention is not limited to this, and an example in which the transmission path of the dot formation data signal SI ′ in the shift register group 442 differs depending on the number of dot formation data SI transmitted from the controller 60 through one signal line will be described below. To do.

  In the head unit 40 of this embodiment, in order to realize generalization, the transmission path of the dot formation data signal SI ′ in the shift register group 442 is variable according to the number of dot formation data SI transmitted from the controller 60. . Further, the number of dot formation data SI transmitted through one signal line can be determined in accordance with the frequency of the received signal (here, the clock signal SCLK). Therefore, the transmission path of the dot formation data signal SI ′ in the shift register group 442 is defined according to the frequency of the clock signal SCLK.

For the following description, as shown in FIG. 5, the upper shift register 442a (SR (H)) and the lower shift register 442b (SR (L)) are divided into a plurality of groups. In the upper shift register 442a, the “first dummy upper group DH1” for storing the upper dot formation data SI of the upper dummy nozzles # 1 to # 4, and the nozzles # 5 to # 184 on the first half side (in the first nozzle group) "First upper group SH1" which is a shift register (corresponding to the first data storage unit) for storing upper dot formation data SI, and nozzles # 185 to # 364 on the rear half side (corresponding to the second nozzle group) Shift register (corresponding to the second data storage unit) “second upper group SH2” and upper dot formation data SI of the second half dummy nozzles # 365 to # 368 are stored. 2 upper dummy group SD2 ”.
Similarly, in the lower side shift register 442b, the lower dot formation data SI of the nozzles # 5 to # 184 is stored as the “first dummy lower group DL1” for storing the lower dot formation data SI of the dummy nozzles # 1 to # 4. The “second lower group SL2” for storing the lower dot formation data SI for the nozzles # 185 to # 364 is stored as the “first lower group SL1”, and the lower dot formation data SI for the dummy nozzles # 365 to # 368 is stored. It is assumed that “second lower dummy group SL2”.
Each group (DH1, DL1, SH1, SL1, DH2, DL2, SH2, and SL2) composed of a plurality of shift registers is connected via multiplexers MX1 to MX13, and the dot formation data signal SI ′ is transmitted by the multiplexers MX1 to MX13. The transmission path becomes variable. Further, a first data input unit SI_1 (corresponding to an input unit) and a second data input unit SI_2 to which the dot formation data signal SI ′ that has been processed by the data processing unit 446 is input are provided.

  Hereinafter, as shown in FIG. 6B, dot formation data SI for 180 nozzles is transmitted by one signal line, and dot formation data SI is transmitted by two signal lines for one nozzle line (FIG. 6B). 16A (corresponding to the first processing)), as shown in FIG. 6C, the dot formation data SI for 360 nozzles is transmitted by one signal line, and the dot formation data by one signal line for one nozzle row A case where SI is transmitted (corresponding to the second process in FIG. 16B) is described as an example.

  First, when the print data SI · SCLK is transmitted from the controller 60 to the head unit 40, the clock signal SCLK is input to the memory IC 45 as shown in FIG. Then, the frequency analysis unit 451 analyzes the frequency of the clock signal SCLK, and the memory IC 45 refers to the control signal table shown in FIG. 15 based on the frequency and determines the third control signal DSW (3). The memory IC 45 inputs the determined third control signal DSW (3) to the shift register group 442 (multiplexers MX1 to MX13) (not shown). By doing so, the dot formation data signal SI 'is transmitted into the shift register group 442 (stored in the shift register) through a transmission path according to the third control signal DSW (3).

  First, the transmission path in FIG. 16A will be described. FIG. 16A shows a case where the number of data transmissions on one signal line is 180 nozzles, and shows a transmission path when the frequency is f1 (Hz). In this case, the memory IC 45 determines the third control signal DSW (3) to “0” from the control signal table (FIG. 15), and sets the third control signal DSW (3) to the shift register group 442 (multiplexers MX1 to MX13). Transmit to. Further, since the dot formation data SI for one nozzle row is transmitted by two signal lines, the dot formation data signal SI ′ transmitted by one signal line is transmitted to the nozzles (# 5 to # 184) on the first half side. The corresponding dot formation data SI, and the dot formation data signal SI ′ transmitted through the other signal line is the dot formation data SI corresponding to the nozzles (# 185 to # 364) on the second half side. The dot formation data signal SI ′ input to the shift register group 442 is a signal after being processed by the data processing unit 446.

  As shown by a thick solid line in FIG. 16A, the dot formation data signal SI ′ input to the first data input unit SI_1 is transmitted in the order of the first lower group SL1 and the first upper group SH1, and the first dummy lower group DL1. In addition, the dot formation data SI is not transmitted to the first dummy upper group DH1. For this purpose, the first multiplexer MX1 inputs the dot formation data signal SI 'input to the first input unit SI_1 to the first lower group SL1 based on the third control signal DSW (3) = [0]. The third multiplexer MX3 and the sixth multiplexer MX6 input the dot formation data signal SI ′ shifted from the first lower group SL1 to the first upper group SH1.

  On the other hand, the dot formation data signal SI ′ input to the second data input unit SI_2 is transmitted in the order of the second lower group SL2 and the second upper group SH2, and is transmitted to the second dummy lower group DL2 and the second dummy upper group DH2. The dot formation data SI is not transmitted. Therefore, based on the third control signal DSW (3) = [0], the seventh multiplexer MX7 and the ninth multiplexer MX9 use the dot formation data SI ′ input to the second data input unit SI_2 as the second lower group SL2. To enter. The eleventh multiplexer MX11 and the thirteenth multiplexer MX13 input the dot formation data signal SI 'shifted from the second lower group SL2 to the second upper group SH2.

  By doing so, the dot formation data SI corresponding to each nozzle (# 5 to # 364) can be input to the shift register corresponding to each nozzle (# 5 to # 364), and the dot formation data SI corresponding to each nozzle (# 5 to # 364) is correctly associated. Ink can be ejected from the nozzles based on the above.

  Next, the transmission path in FIG. 16B will be described. FIG. 16B shows a case where the number of data transmissions on one signal line is 360 nozzles, and shows a transmission path when the frequency is f2 (Hz). In this case, the memory IC 45 determines the third control signal DSW (3) to be “1” and transmits the third control signal DSW (3) to the shift register group 442 (multiplexers MX1 to MX13). In this case, since the dot formation data SI for one nozzle is transmitted through one signal line, the dot formation data signal SI ′ is input only to the first input unit SI_1 after the processing of the dot formation data processing unit 446. Is done.

  As shown by a thick solid line in FIG. 16B, the dot formation data SI input to the first data input unit SI_1 includes the second lower group SL2, the first lower group SL1, the second upper group SH2, the first upper group SH1, Are transmitted in this order. Therefore, based on the third control signal DSW (3) = [1], the seventh multiplexer MX7 and the ninth multiplexer MX9 use the dot formation data signal SI ′ input to the first data input unit SI_1 as the second lower group. Input to SL2. Then, the first multiplexer MX1 inputs the dot formation data signal SI 'shifted from the second lower group SL2 to the first lower group SL1. The third multiplexer MX3, the eleventh multiplexer MX11, and the thirteenth multiplexer MX13 input the dot formation data signal SI ′ shifted from the first lower group SL1 to the second upper group SH2, and the sixth multiplexer MX6 receives the second multiplexer MX6. The dot formation data signal SI ′ shifted from the upper group SH2 is input to the first upper group SH1.

  As described above, when the transmission method is different depending on the type of the controller 60 and the number of dot formation data SI transmitted through one signal line is different, the transmission path of the shift register group 442 needs to be different. If the transmission path of the shift register group 442 cannot be switched according to the number of dot formation data SI transmitted by one signal line, it is necessary to manufacture a dedicated head unit 40 corresponding to the controller 60. is there. On the other hand, in the head unit 40 of this embodiment, the shift register is divided into a plurality of groups, and each group is connected via the multiplexers MX1 to MX13, so that the dot formation data according to the transmission method from the controller 60 is obtained. The transmission path of the signal SI ′ can be changed, and the head unit 40 can be generalized.

  Further, in the head unit 40 of the present embodiment, the memory IC 45 analyzes the frequency of the received signal (clock signal SCLK) from the controller 60, and sends the third control signal DSW (3) to the shift register group 442 (multiplexers MX1 to MX13). , The transmission path of the shift register group 442 can be automatically switched. For this reason, in the manufacturing process of the printer 1 or when the head unit 40 is replaced, an operation for associating the printer 1 with the head unit 40 (for example, an operation for storing a control signal defining a transmission path of the shift register group 442 in the memory IC) There is no need to do this, and the work can be facilitated. The third control signal DSW (3) may be determined by analyzing the frequency of the dot formation data signal SI without being limited to analyzing the frequency of the clock signal SCLK.

  FIG. 16 shows an example in which the dot formation data SI corresponding to the dummy nozzle is not transmitted from the controller 60. However, when the dot formation data SI corresponding to the dummy nozzle is transmitted from the controller 60, the first dummy The multiplexer MX is controlled to transmit the dot formation data signal SI to the lower group DL1, the first dummy upper group DH1, the second dummy lower group DL2, and the second dummy upper group DH2. In the control signal table of FIG. 15, the third control signal DSW (() has the frequency f1 when the dot formation data SI for 180 nozzles is transmitted and the frequency f2 when the dot formation data SI for 360 nozzles is transmitted. 3). However, the present invention is not limited to this. Even when the dot formation data SI of the dummy nozzle is transmitted (184 nozzles and 368 nozzles), the frequency of the clock signal SCLK is different, so the third control signal DSW (3 ) May be set in the control signal table.

  Further, not only the case of transmission from the dot formation data SI of the nozzles (# 1 to # 5) on the first half side in the nozzle row direction but also the nozzles (# 368 to # 364 to) on the second half side of the nozzle row. In some cases, the dot formation data SI is transmitted. In this case, the multiplexer MX may be controlled so that the previous dot formation data SI is input to the shift registers (second lower group SL2 and second upper group SH2) of the latter half nozzle.

=== Other Embodiments ===
Each of the above embodiments has been described mainly for a printing system having an ink jet printer, but includes disclosure of processing of the head unit and the like. The above-described embodiments are for facilitating understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<Print data transmission method>
In the above-described embodiment, as illustrated in FIG. 7, the head unit 40 that processes the received signal SI transmitted according to the three transmission methods according to the frequency is illustrated, but the present invention is not limited thereto. For example, only the second third data processing unit 71 (differential circuit 74) is provided, and the second reception signal SI (2) according to the second transmission scheme and the third reception signal SI ( The head unit 40 which makes the process of 3) different may be used. Further, the head unit 40 that makes the processing of the first received signal SI (1) according to the first transmission scheme and the received signal SI (3) according to the third transmission scheme different according to the frequency may be used. The head unit 40 may be configured so that the processing of the first reception signal SI (1) according to the one transmission method differs from the processing of the second reception signal SI (2) according to the second transmission method.

<Processing change by print mode>
In the above-described embodiment, the method of transmitting data to the head unit 40 is different for each model of the printer 1 (for each type of controller 60), but is not limited thereto. For example, even in the same printer 1, the print data transmission method may differ depending on the print mode. For example, in the early mode, the number of data transmitted in a predetermined transmission period T is increased as shown in FIG. 7B, and in the clean mode, the number of data transmitted in the predetermined transmission period T as shown in FIG. 7A. May be reduced to reduce noise. In such a case, even in the data processing performed by the same printer 1, the head unit 40 analyzes the frequency of the reception signal (SCLK) and performs data processing according to the frequency.

<Common differential circuit>
In the above-described embodiment, the received signal SI (2) whose potential is level-shifted from GND by the second transmission method (FIG. 7B) and the received signal SI (3) differentially transmitted by the third transmission method (FIG. 7C). Is input to the common differential circuit 74 and converted into a 3.3 V amplitude signal whose L level potential is GND, but is not limited thereto. For example, if a comparison circuit in which a reference potential is set according to the reception signal SI (2) whose potential is level-shifted by the second transmission method is provided, and the potential of the second reception signal SI (2) is equal to or higher than the reference potential, If 3.3V is output and the potential of the second reception signal SI (2) is less than the reference potential, 0V may be output. However, the circuit configuration can be simplified by processing the second reception signal SI (2) and the third reception signal SI (3) by the common differential circuit 74 as in the above-described embodiment.

<About fluid ejection device>
In the above-described embodiment, the ink jet printer is exemplified as the fluid ejecting apparatus, but the present invention is not limited thereto. If it is a fluid ejecting apparatus, it can be applied to various industrial apparatuses, not a printer (printing apparatus). For example, a textile printing apparatus for applying a pattern to a fabric, a display manufacturing apparatus such as a color filter manufacturing apparatus or an organic EL display, a DNA chip manufacturing apparatus for manufacturing a DNA chip by applying a solution in which DNA is dissolved to a chip, and the like. Also, the present invention can be applied. The fluid is not limited to liquid (ink) but may be, for example, powder.

  The fluid ejection method may be a piezo method in which fluid is ejected by applying a voltage to the drive element (piezo element) to expand and contract the ink chamber, or bubbles are generated in the nozzle using a heating element. It is also possible to use a thermal method in which liquid is ejected by the bubbles.

<About the head unit 40>
In the above-described embodiment, the head portion (nozzle, piezo element, etc.) that ejects the fluid, and the memory IC 45 and the control IC 44 (data processing unit 46) that analyze the frequency are the same head unit 40, but this is not a limitation. . The head portion for ejecting the fluid may be separated from the memory IC 45 and the control IC 44. In this case, the memory IC 45 and the control IC 44 correspond to the head driving device, and the head portion that ejects fluid corresponds to the head.

CP computer, 1 printer, 10 paper transport mechanism, 20 carriage movement mechanism, 30 drive signal generation circuit, 40 head unit 40, HD head, HC head control unit, 41 case, 42 flow path unit, 421 common ink chamber, 422 ink Supply path, 423 pressure chamber, 424 nozzle, 43 piezo element group, 431 piezo element, 44 control IC, 442 shift register group, 443 latch circuit group, 444 decoder group, 445 switch group, 446 data processing unit, 45 memory IC, 451 Frequency analysis unit, 46 Head side cable, 47 Relay board, 50 Sensor, 60 Controller, 61 ASIC, 62 Main unit side memory, 63 CPU, 65 Control unit, 651 Data transmission unit, 652 Output buffer, 653 Transmission control unit, CB main body side substrate, 70 first data processing unit, 71 second third data processing unit, 72 transmission gate, 73 inversion unit, 74 differential circuit

Claims (8)

When data for ejecting fluid is received from a head for ejecting fluid, the frequency of the data is analyzed,
Process the received data according to the frequency,
A controller that ejects fluid from the head based on the processed data;
A head drive device comprising: The head drive device according to claim 1,
The control unit includes a comparison circuit and a differential circuit, determines a control signal corresponding to the frequency of the received data, and operates either the comparison circuit or the differential circuit according to the control signal. Process the received data,
Head drive device. The head driving device according to claim 1 or 2, wherein
The controller is
(1) When the frequency of the received data is the first frequency,
(2) By inputting the received data to the comparison circuit, a first potential is output when the received potential of the data is equal to or higher than a first reference potential, and the received potential of the data is the first potential. Output data for outputting a second potential different from the first potential is obtained when the reference potential is less than
(3) ejecting fluid from the head based on the output data;
Head drive device. The head driving device according to any one of claims 1 to 3,
The controller is
(1) When the frequency of the received data is a second frequency,
(2) By inputting the received data to the first input unit of the differential circuit and inputting a constant potential to the second input unit of the differential circuit,
When the potential based on the difference between the data potential input to the first input unit and the constant potential input to the second input unit is equal to or higher than a second reference potential, the first potential is output, and the difference is output. When the potential based on is less than the second reference potential, output data for outputting a second potential different from the first potential is obtained,
(3) ejecting fluid from the head based on the output data;
Head drive device. The head driving device according to any one of claims 1 to 4, wherein:
The controller is
(1) When the frequency of the received data is a third frequency,
(2) By inputting a non-inverted signal of the received data to the first input unit of the differential circuit and inputting an inverted signal of the received data to the second input unit of the differential circuit ,
When the potential based on the difference between the potential of the non-inverted signal input to the first input unit and the potential of the inverted signal input to the second input unit is equal to or higher than a third reference potential, the first potential is output. When the potential based on the difference is less than the third reference potential, output data that outputs a second potential different from the first potential is acquired,
(3) ejecting fluid from the head based on the output data;
Head drive device. The head driving device according to any one of claims 1 to 5,
When data transmitted by differential transmission is received, a non-inverted signal of the received data is input to the first input unit of the differential circuit and received to the second input unit of the differential circuit Input and process an inverted signal of the data,
In the case where data having an L-level potential shifted from a ground potential to a predetermined potential and data transmitted by single-ended transmission is received, the data received at the first input section of the same differential circuit And processing by inputting a constant potential to the second input part of the same differential circuit,
Head drive device. The head driving device according to any one of claims 1 to 6,
The head is
A first nozzle group that is a plurality of nozzles for ejecting fluid; a second nozzle group that is a plurality of nozzles for ejecting fluid;
A first data storage unit that stores the data relating to the fluid ejection of the first nozzle group; a second data storage unit that stores the data relating to the fluid ejection of the second nozzle group;
An input unit for inputting the data processed according to the frequency of the received data;
The control unit, according to the frequency of the received data,
A first process for storing the data input to the input unit in one of the first data storage unit and the second data storage unit;
The data input to the input unit is selected to perform a second process for storing the data in the first data storage unit and the second data storage unit.
Head drive device. (1) a head for ejecting fluid;
When data for ejecting fluid from the head is received, the frequency of the data is analyzed, the received data is processed according to the frequency, and fluid is ejected from the head based on the processed data And
A head drive device comprising:
(2) A main control unit communicably connected to the head driving device, the main control unit transmitting the data for ejecting fluid from the head to the head driving device;
A fluid ejecting apparatus having (3).

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