METHOD OF SENDING PRINT DATA

One embodiment of the present invention provides a method of sending print data, including: generating a first data part with a fixed data length; generating a second data part with a variable data length; and combining the first and second data parts in a predetermined order and sending the resulting print data. The first data part includes multiple information pieces. The second data part is capable of including multiple additional information pieces. A first information piece included in the first data part indicates presence or absence of each additional information piece in the second data part. The second information piece includes multiple pieces of synthesized data. In the sending, the multiple pieces of synthesized data are each subjected to bit division, and portions of the pieces of synthesized data subjected to the bit division which have a smaller bit length are continuously arranged in a single packet.

BACKGROUND

Field

The present disclosure relates to a technique for sending print data.

Description of the Related Art

Printing apparatuses have print heads in which multiple nozzles for ejecting liquids such as inks are arrayed. For example, in a case where a print job is input into such a printing apparatus from an external apparatus (such as a personal computer), print data based on this print job is sent to the print head. The print head ejects the liquids based on the sent print data. This print data is sent in a predetermined unit and is called “packets” or the like.

Japanese Patent Laid-Open No. H5-347649 discloses that, in a case of serially sending data, the data to be sent is given information for identifying the data length of this data to make the size of each unit pieces of data to be sent variable.

SUMMARY

Printing apparatuses in recent years have a larger variety of functions than conventional ones. Accordingly, the volume of print data to be sent tends to be large, and there is a demand to quickly send such print data. However, it is hard to say that print data can be efficiently sent in those printing apparatus with the technique of Japanese Patent Laid-Open No. H5-347649. Thus, there is a demand for a further improvement for sending of print data.

In view of the above, an object of the present disclosure is to efficiently send print data in a printing apparatus having a variety of functions.

One embodiment of the present invention provides a method of sending print data in a printing apparatus by a serial transfer method, including: generating a first data part with a fixed data length; generating a second data part with a variable data length; and combining the first data part and the second data part in a predetermined order and sending the resulting print data, in which the first data part includes a plurality of information pieces, the second data part is capable of including a plurality of additional information pieces, a first information piece being one of the plurality of information pieces included in the first data part indicates presence or absence of each of the plurality of additional information pieces in the second data part, a second information piece being one of the plurality of information pieces includes a plurality of pieces of synthesized data, and in the sending, the plurality of pieces of synthesized data are each subjected to bit division, and portions of the pieces of synthesized data subjected to the bit division which have a smaller bit length are continuously arranged in a single packet.

DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present disclosure will be specifically described below with reference to the accompanying drawings. It is to be noted that the following embodiments are not intended to limit the invention according to the claims more than necessary. Moreover, although multiple features are described in the following embodiments, not all of these multiple features are necessarily essential to the present disclosure's solution to the problem. These multiple features may be combined as desired. Furthermore, in the accompanying drawings, identical or similar components are denoted by the same reference numeral, and overlapping description may be omitted.

First Embodiment

FIGS.1A and1Bare diagrams illustrating a configuration of a printing apparatus in a first embodiment. Specifically,FIG.1Ais a schematic perspective view illustrating outer appearance of the printing apparatus, andFIG.1Bis a block diagram illustrating a configuration of a circuit block inside the printing apparatus.

As illustrated inFIG.1A, a printing apparatus1has a connector11and a discharge tray12. The printing apparatus1is connected to an external information processing apparatus (not illustrated), such as a personal computer, via wired communication through the connector11(or via wireless communication). The external information processing apparatus may be expressed as a host apparatus or the like. One or more sheets are loaded on the printing apparatus1. Based on a print job received from the external information processing apparatus, the printing apparatus1performs printing on a sheet, and discharges the printed sheet onto the discharge tray12.

The printing apparatus1is configured to capable of performing printing on a sheet by an ink jet method, and further has a conveyance mechanism not illustrated which conveys a sheet and a later-described print head19(seeFIGS.1B and12) which performs printing on the conveyed sheet. While publicly known heads such as a line head and a serial head can be employed as the print head19, a line head is employed in the present embodiment.

FIG.1Bis a block diagram illustrating a configuration of a circuit block inside the printing apparatus. The operation timing with which this circuit block operates is set with later-described pieces of synthesized data p1to p4. The setting of the operation timing with the pieces of synthesized data will be specifically described later (seeFIGS.10, etc.).

As illustrated inFIG.1B, the printing apparatus1has a control circuit board13, a head substrate14, and multiple element substrates15. The control circuit board13is provided in the main body of the printing apparatus, and the head substrate14and the element substrates15are provided in the print head19. The control circuit board13generates later-described print data Dt based on a print job input through the connector11, and outputs the generated print data Dt to the head substrate14(seeFIG.2). A single flexible circuit board16is connected to each of the multiple element substrates15. Each of the multiple element substrates15is electrically and communicatively connected to the head substrate14through the corresponding flexible circuit board16. This configuration enables the head substrate14to send each of the multiple element substrates15the corresponding print data Dt through the corresponding flexible circuit board16.

Here, the multiple element substrates15are arranged along one direction, and later-described multiple printing elements201(seeFIG.4) are arrayed along the one direction in each individual element substrate15. Multiple nozzles for ejecting droplets of liquids, such as inks, are arrayed in the print head19, and the printing elements201are provided respectively for these nozzles. Ink droplets are ejected from the nozzles by driving the printing elements201. Publicly known elements may be used as the printing elements201. In the present embodiment, electrothermal conversion elements (which are called “heater elements” or “resistive elements”) are used but piezoelectric elements may be used instead of the electrothermal conversion elements.

The control circuit board13has a processor131that performs calculation processing for implementing functions of the printing apparatus1. For example, the processor131functions as a sending unit that generates the print data Dt and sends the generated print data Dt to the element substrates15. As will be described later in detail, the processor131implements this sending unit by having a first generation unit1311, a second generation unit1312, and a third generation unit1313.

Incidentally, a semiconductor device such as an application-specific integrated circuit (ASIC) or a programmable logic device (PLD) is typically used as the processor131. Alternatively, in another embodiment, the processor131may be configured of a central processing unit (CPU) and a memory. For this reason, each function of the processor131may be implemented with hardware or software or with a combination of hardware and software.

The print data Dt is sent in a predetermined unit by a serial transfer method, and a piece of data to be sent in a single operation is called a packet or the like. In the present embodiment, the control circuit board13serially generates the print data Dt in units of packets and then serially sends the generated print data Dt to the element substrates15through the head substrate14. Incidentally, a constituent element other than the control circuit board13may generate the print data Dt. For example, the head substrate14may serially generate the print data Dt in units of packets and then serially send the print data Dt to the element substrates15.

FIG.2is a block diagram illustrating a configuration of the print head19having the head substrate14and the multiple element substrates15. Each of the multiple element substrates15receives the print data Dt as well as a clock signal CLK_A and a latch signal Lt sent from the control circuit board13through the flexible circuit board16. The clock signal CLK_A makes it possible for two or more elements to synchronize with one another with at least one of rise edges of the waveform of this signal (shift from a low level to a high level) or fall edges (shift from the high level to the low level). The latch signal Lt makes it possible to latch the individual signals forming the print data Dt at a latch circuit not illustrated with the rise edges or the fall edges of the waveform of this signal.

FIG.3is a general timing chart of sending of data, illustrating the print data Dt to be sent in a single operation and the clock signal CLK_A and the latch signal Lt to be input into the element substrates15along with this print data. As will be described later in detail, the print data Dt includes multiple information pieces inf11, inf12, and so on (simply referred to as “information piece(s) inf” unless otherwise distinguished from one another), and each individual information piece inf includes multiple signals. For example, the information piece inf11(the first group inFIG.3) is m-bit data including signals a(0), a(1), a(2), . . . , a(m), where m and n are integers of 1 or more. The information piece inf12(the second group inFIG.3) is n-bit data including signals b(0), b(1), b(2), . . . , b(n). Incidentally, bit data includes multiple signals, and the value of each individual signal can be expressed as “bit value” as well. Note that, considering the configuration of the circuit to receive the data, the number of bits in each group is preferably the same (m=n is preferable in this example).

In the example ofFIG.3, the signal a(0) and so on mentioned above are sequentially input based on the rise edges and fall edges of the clock signal CLK_A at times t0, t1, t2, and so on, and then the signals a(0) and so on thus sent are latched at a time tp at which the latch signal Lt forms a rise edge. Thus, the print data Dt to be sent in a single operation is defined between a fall edge of the latch signal Lt to the next rise edge of the latch signal Lt.

FIG.4illustrates an example configuration of each individual element substrate15. Each element substrate15includes has printing elements2011to201k, driving elements2021to202k, and logic elements2031to203k. Each element substrate15further has multiple ejection sensors210, multiple residue removal units204, a temperature sensor205, multiple heating elements206, logic units2071to2076, signal output units2081and2082, and a processor209. Incidentally, the printing elements2011to201k, the driving elements2021to202k, and the logic elements2031to203kwill be referred to as “printing element(s)201”, “driving element(s)202”, and “logic element(s)203”, respectively, unless otherwise needed to be distinguished from one another. It is to be noted that such a rule of representation will be applied similarly to other constituent elements herein.

The multiple driving elements202are each connected in series to a corresponding one of the printing elements201. As each individual driving element202, a publicly known switching elements, such as a metal oxide semiconductor (MOS) transistor, is used. The driving element202electrifies and drives the printing element201by turning into a conducting state, and stops the driving by turning to a non-conducting state. In the case where the driving element202is a MOS transistor, the gate terminal is connected to the output of the logic element203, and the source terminal and the drain terminal are arranged so as to form a current path between the driving element202and the printing element201. As for the inputs of each logic element203, the logic element2031, for example, receives a signal sel(1) from the logic unit2075and a signal HEAT from the logic unit2076. This applies also to the other logic elements. The logic element2032receives a signal sel(2) from the logic unit2075and the signal HEAT from the logic unit2076, and the logic element203kreceives a signal sel(k) from the logic unit2075and the signal HEAT from the logic unit2076.

A single ejection sensor210is provided for a single printing element201. Thus, the number of ejection sensors210is equal to the number of printing elements201. Each individual ejection sensor210is capable of detecting whether an ink droplet has been properly ejected as a result of driving the corresponding printing element201. The logic unit2071is capable of controlling the driving of each individual ejection sensor210and obtaining the result of the detection by the ejection sensor210. In this way, the processor209can receive the result of the detection by each individual ejection sensor210from the logic unit2071.

A single residue removal unit204is provided for a single printing element201. Thus, the number of residue removal units204is equal to the number of printing elements201. Each individual residue removal unit204includes electrodes, for example. The logic unit2072is capable of driving each residue removal unit204by applying a predetermined voltage to the residue removal unit204based on a signal from the processor209, and thereby removing ink residues that can be present inside ink flow channels near the corresponding printing element201.

At least one temperature sensor205is arranged at a predetermined position on or in each element substrate15(e.g., on its peripheral edge portion or the like) and is capable of detecting the temperature of the element substrate15. The logic unit2073is capable of controlling the driving of the temperature sensor205and obtaining the result of the detection by the temperature sensor205. In this way, the processor209can receive the result of the detection by the temperature sensor205from the logic unit2073.

The multiple heating elements206are arranged at predetermined positions on or in the element substrate15(e.g., on its peripheral edge portions). As each individual heating element206, an electrothermal conversion element is used, like the printing elements201. The logic unit2074drives the heating elements206based on a signal from the processor209to thereby adjust the temperatures of the element substrates15. Incidentally, in the present embodiment, electrothermal conversion elements are used as both the printing elements201and the heating elements206, but the heating elements206will also be called “sub-heaters” or “sub-heater elements” to be distinguished from the printing elements201.

The signal output unit2081outputs analog signals indicating the results of the detections by the ejection sensors210and the temperature sensor205and the results of the driving of the residue removal units204to the control circuit board13through an output terminal2081T based on a signal from the processor209. The signal output unit2082outputs digital signals indicating the results of the detections by the ejection sensors210and the temperature sensor205and the results of the driving of the residue removal units204to the control circuit board13through an output terminal2082T based on a signal from the processor209. As the signal output units2081and2082, publicly known multiplexers may be used. The signal output units2081and2082output one or both of the above analog signals and the digital signals to the control circuit board13.

The processor209controls the driving of each element described above by performing predetermined calculation processing. As will be described later in detail, the processor209includes a first processing unit2091, a second processing unit2092, and a third processing unit2093. Like the processor131, each function of the processor209may be implemented with hardware or software.

As described above, the circuit block illustrated inFIG.1Bhas the element substrates15, each element substrate15has the whole circuit illustrated inFIG.4, and the circuit illustrated inFIG.4has the processor209, the logic elements2031to203k, and the logic units2071to2076.

FIG.5illustrates an example data structure of the print data Dt being data (serial data) to be sent in a single operation. The print data Dt includes a first data part D1and can additionally include a second data part D2. That is, the first data part D1is always included in the print data Dt but the second data part D2can be omitted from the print data Dt as appropriate. The data part D1includes multiple information pieces inf11to inf15, and their data length (data size) is fixed. The data part D2is capable of containing multiple additional information pieces inf21to inf26, and their data length is variable depending on the presence or absence of each additional information piece.

First, the constituent elements of the data part D1, which is the essential data part, specifically, the information pieces inf11to inf15will be described.

The information piece inf11forms notification data which forms one form of the header of the print data Dt (start condition) and indicates start of communication.

The information piece inf12indicates the presence or absence of each of the multiple additional information pieces inf21to inf26, which can be included in the data part D2. As mentioned above, the data length of the data part D2is variable depending on the presence or absence of the multiple additional information pieces inf21to inf26, and the data length of the data part D2can be figured out by using the data of the information piece inf12. Due to such a characteristic of the information piece inf12, the information piece inf12will be referred to as “additional information identifier”, skip flag”, or the like.

The information piece inf13forms data for selecting which heater to drive (heater selection data). Incidentally, as will be described later in detail, the information piece inf13includes k bits (seeFIG.8A), and the circuit configuration is such that these bits and the printing elements201inFIG.4are in a one-to-one correspondence, and only the printing elements201corresponding to bits to which 1 is written as sel are driven. Also, as will be described later in detail, the data of the information piece inf13determines the timing of the signal HEAT (seeFIG.10).

The information piece inf14forms definition data for defining the pulse waveforms and driving timing of driving signals for the printing elements201. Due to such a characteristic of the information piece inf14, the information piece inf14will be referred to as “heat pulse definition data”.

The information piece inf15is arranged at the end of the print data Dt and forms diagnosis data for diagnosing whether the print data Dt has been properly sent.

Next, the constituent elements of the data part D2, which is an additional data part, specifically, the additional information pieces inf21to inf26will be described.

The additional information piece inf21forms first adjustment data indicating whether to heat the element substrate15with the heating elements206. As mentioned earlier, the heating elements206are referred to also as “sub-heaters” or “sub-heater elements”.

The additional information piece inf22forms first selection data indicating that outputting of the analog signals from the signal output unit2081to the control circuit board13is to be selected.

The additional information piece inf23forms second selection data indicating that outputting of the digital signals from the signal output unit2082to the control circuit board13is to be selected.

The additional information piece inf24forms first detection data indicating whether to obtain the results of the detection by the ejection sensors210.

The additional information piece inf25forms second detection data indicating whether to obtain the result of the detection by the temperature sensor205.

The additional information piece inf26forms second adjustment data indicating whether to remove ink residues with the residue removal units204.

As described above usingFIG.5, the data part D1contains information that is actually needed to execute printing or information directly related to the printing operation. The data part D2, on the other hand, contains information that is needed at the preparation stage before the execution of the printing or information indirectly related to the printing operation.

FIG.6illustrates the content of the information piece inf12, which is an additional information identifier. In the present embodiment, the information piece inf12is 8-bit data. The first bit indicates the presence or absence of the additional information piece inf21. The second bit indicates the presence or absence of the additional information piece inf22. The third to sixth bits likewise indicate the presence or absence of the corresponding respective additional information pieces inf. The seventh and eighth bits are dummy data (NULL) for making the data size of the information piece inf12eight bits. In the present embodiment, each individual bit takes a binary value of “0” or “1”. Here, “0” indicates presence whereas “1” indicates absence. For example, in a case where the first bit is “0”, the data part D2includes the additional information piece inf21. In a case where the first bit is “1”, the data part D2does not include the additional information piece inf21.

FIGS.7A to7Dillustrates versions of the print data Dt (data to be sent in a single operation) to be used in four modes (first to fourth modes) for sending print data.

FIG.7Aillustrates the data structure of the print data Dt in the first mode. The first mode refers to a sending mode in a case where all functions are selected. As illustrated inFIG.7A, the first to sixth bits in the information piece inf12, which is an additional information identifier, are “000000” (the first, second, . . . , sixth bits in this order from the head). In this case, the print data Dt includes the information pieces inf11to inf15as the data part D1and further includes all of the additional information pieces inf21to inf26as the data part D2. Accordingly, the data length of the print data Dt is longest.

FIG.7Billustrates the data structure of the print data Dt in the second mode. The second mode refers to a sending mode in a case where driving of the sub-heaters, detection by the ejection sensors, detection by the temperature sensor are selected. As illustrated inFIG.7B, the first to sixth bits in the information piece inf12are “011001”. In this case, the print data Dt includes the information pieces inf11to inf15as the data part D1and further includes the additional information pieces inf21, inf24, and inf25as the data part D2. The additional information pieces inf22, inf23, and inf26are omitted.

FIG.7Cillustrates the data structure of the print data Dt in the third mode. The third mode refers to a sending mode in a case where driving of the sub-heaters and detection by the temperature sensor are selected. As illustrated inFIG.7C, the first to sixth bits in the information piece inf12are “011101”. In this case, the print data Dt includes the information pieces inf11to inf15as the data part D1and further includes the additional information pieces inf21and inf25as the data part D2. The additional information pieces inf22, inf23, inf24, and inf26are omitted.

FIG.7Dillustrates the data structure of the print data Dt in the fourth mode. The fourth mode refers to a sending mode in which only driving of the sub-heaters is selected. As illustrated inFIG.7D, the first to sixth bits in the information piece inf12are “111111”. In this case, the print data Dt includes the information pieces inf11to inf15as the data part D1but does not include the data part D2(all of the additional information pieces inf21to inf26are omitted), so that the data length of the print data Dt is shortest.

FIG.8Aillustrates the bit array of the information piece inf13inFIG.5. The information piece inf13includes bits sel(1) to sel(k) and is sent in the order of the bits sel(1), sel(2), . . . , sel(k). The bits in the information piece inf13are held in the logic unit2075inFIG.4. The data held in the logic unit2075will now be described usingFIG.4. The bits sel(1), sel(2), . . . , sel(k) held in the logic unit2075undergoes an AND operation with the signal HEAT output from the logic unit2076. Thus, the signal HEAT is input into the driving elements202corresponding to the bits to which 1 is written among the bits sel(1), sel(2), . . . , sel(k). The signal HEAT is not input into the driving elements202corresponding to the bits to which 0 is written since the result of the AND operation is always 0. Only the printing elements201connected to the driving elements into which the signal HEAT is input turn to a conducting state, thereby heating the ink. At this time, bubbles are generated in the ink and eject the ink from corresponding nozzles not illustrated. As a result, a printing operation is performed. With the above operation, the bits sel(1), sel(2), . . . , sel(k) function as data that selects whether to perform a printing operation with the printing elements2011,2012, . . . ,202k.

FIG.8Billustrates the bit array of the information piece inf14inFIG.5. The information piece inf14is sent in the order of the bits d(1) to d(4), p1(9) to p4(9), p1(1) to p1(8), p2(1) to p2(8), p3(1) to p3(8), and p4(1) to p4(8). The bits in the information piece inf14are held in the logic unit2076inFIG.4. The bits d(1) to d(4) at the head are dummy bits that are provided in order to adjust the bit length in the horizontal direction inFIG.8Bto eight bits, and do not affect the operation in the present embodiment.

FIG.8Cis a diagram illustrating a conventional example of sending the bits p1(1) to p1(9) in the form of a single continuous piece of data as a mode of sending the information piece inf14, explaining a difference from the present embodiment. InFIG.8C, each of the bits p2(1) to p2(9), p3(1) to p3(9), and p4(1) to p4(9) is likewise sent in the form of a single continuous piece of data.

In serial communication of the print data Dt, a circuit that converts serial data into parallel data (a serial-to-parallel conversion circuit, hereinafter referred to as “serial-parallel conversion circuit”) is used. The serial-parallel conversion circuit is generally configured such that the minimum unit for the fixed bit width (the number of bits into which serial data can be converted into parallel data in a single conversion operation) is set to 8 bits (=1 byte). Thus, inFIG.8C, the information piece inf14including the dummy bits d(1) to d(28) is 8-byte data as a whole.

On the other hand, in the present embodiment, as illustrated inFIG.8B, the single most significant bit in each of the pieces of data p1to p4(specifically, p1(9), p2(9), p3(9), and p4(9)) is gathered in 1 byte. In this way, the data of the information piece inf14can be formed with 5 bytes.

FIG.9is a diagram of a configuration of the logic unit2076inFIG.4. A clock CLK_B is input into a counter901. The counter901counts the edges of the clock CLK_B and outputs a signal CNT(9:1), which is a 9-bit signal. This signal CNT is input into a comparator902.

Synthesized data p1(9:1) is also input into the comparator902. The synthesized data p1(9:1) represents 9-bit data in which the bits p1(9) to p1(1) inFIG.8Bare arranged in this order from higher to lower-order bits. Similarly, synthesized data p2(9:1), synthesized data p3(9:1), and synthesized data p4(9:1) are input into the comparator902.

It is to be noted that the terms “bit(s)” and “data” are distinguished in the following depending on the description, but the bits p1(9) to p1(1) and the synthesized data p1(9:1) basically mean the same. This rule of representation will be applied similarly to p2to p4as well.

The comparator902compares the signal CNT and the pieces of synthesized data p1(9:1) to p4(9:1) to generate the signal HEAT. The signal HEAT generated by the comparator902is output from the logic unit2076. Details will be described later usingFIG.10.

In the present embodiment, while the pieces of synthesized data p1(9:1) to p4(9:1) each function as multi-bit data with nine bits, this 9-bit data is arranged in a non-continuous layout by performing bit division on part of the 9-bit data as illustrated inFIG.8B. Specifically, in this example, the bits p1(9) to p4(9) after the bit division are organized and continuously arranged to be included in the most significant packet (8-bit data), and dummy data is assigned as the remaining bits in this packet. Incidentally, separating a bit in multi-bit data (9-bit data in this example) or arranging individual pieces of multi-bit data in a non-continuous layout as indicated by the bit array of the information piece inf14will be described herein as “extracting”.

FIG.10is a diagram for explaining the operation of generating the signal HEAT by the logic unit2076inFIG.4. InFIG.10, the vertical axis represents the count value of the signal CNT. The signal CNT is a signal obtained by counting the edges of the clock CLK_B not illustrated. In this example, the counting of the signal CNT starts at a time t90. The signal level of the signal HEAT at this time is L.

At a time t91, the signal CNT matches the data p1, and the signal level of the signal HEAT shifts to H. Subsequently, the signal CNT matches the data p2at a time t92, the data p3at a time t93, and the data p4at a time t94, and the level of the signal HEAT shifts to L, H, and L in this order.

FIG.11Ais a diagram explaining a state of operation of a printing element201, a driving element202, and a logic element203. A logic element203j(j=1, 2, . . . , k) receives a bit sel(j) from the logic unit2075and the signal HEAT from the logic unit2076. The logic element203jincludes a two-input AND element, and brings a driving element202jinto a conducting state (illustrated as “ON” inFIG.11A) in intervals in which the bit sel(j) and the signal HEAT are both at their respective levels H. The logic element203jbrings the driving element202jto a non-conducting state in intervals in which the signal HEAT is at the level L (illustrated as “OFF” inFIG.11A). In the case where the driving element202jturns to the conducting state, a current flows into a printing element201j. As a result, the ink is heated, and an ink droplet is ejected.

FIG.11Bis a diagram explaining a state different fromFIG.11A. In this state, the level of the bit sel(j) always remains at L. Thus, the driving element202jis in the non-conducting state regardless of the level of the signal HEAT, so that no ink droplet is ejected.

In the operations illustrated inFIGS.11A and11B, the bit sel(j) functions as a signal for selecting whether or not to drive the printing element201jand the signal HEAT functions as a signal that determines the timing to drive the printing element201j.

FIG.12illustrates a mode of sending the print data Dt to be sent in units of packets in a case of performing printing on three sheets Sh. As mentioned earlier, a line heat is used as the print head19in the present embodiment. Thus, the print head19is capable of performing printing on the entirety of each sheet Sh in the sheet width direction at once while moving relative to the sheet Sh in the sheet length direction. In the printing apparatus1, the sheets Sh are actually moved relative to the print head19to perform printing on the moved sheets Sh, but the print head19is illustrated inFIG.12as being moved relative to the three sheets Sh to facilitate understanding.

The horizontal axis inFIG.12is a temporal axis. For example, the printing apparatus1is activated or initialized at a time t0. Then, in response to input of a print job, printing of the first sheet Sh is started at a time t1, and the printing of the first sheet Sh is completed at a time t2. Printing of the second sheet Sh is started at a time t3, and the printing of the second sheet Sh is completed at a time t4. Similarly, printing of the third sheet Sh is started at a time t5, and the printing of the third sheet Sh is completed at a time t6. The printing process for the input print job is completed at the time t6.

In the period from the time t0to the time t1, the print data Dt is sent in the first mode (seeFIG.7A) or the second mode (seeFIG.7B) in units of packets. As a result, functions such as temperature adjustment for start-up for printing and detection by the ejection sensors are set up.

In the period from the time t1to the time t2, the print data Dt is sent in the third mode (seeFIG.7C) or the fourth mode (seeFIG.7D) in units of packets. In the third mode, the data to be sent is reduced to limit the functions to the printing operation, the temperature adjustment, and the detection by the ejection sensors. This shortens the data cycle (ejection cycle). In the fourth mode, the data to be sent is reduced to limit the functions to the printing operation. This makes the amount of data to be sent smallest and makes the data cycle (ejection cycle) shortest.

In the period from the time t2to the time t3, which is the period from the completion of the printing of the first sheet Sh to the start of the printing of the second sheet Sh, the print data Dt is sent in the second mode (seeFIG.7B) in units of packets.

In the period from the time t3to the time t4and the period from the time t5to the time t6, the print data Dt is sent in the third mode or the fourth mode, as in the period from the time t1to the time t2. In the period from the time t4to the time t5, the print data Dt is sent in the second mode, as in the period from the time t2to the time t3. After the time t6, the print data Dt is sent in the first mode or the second mode, so that initialization of all functions, a stand-by operation for printing, and the like are performed.

As described above, the period in which the printing apparatus1is activated is divided into a period in which the print head19actually executes printing (printing period (first period)) and a period in which the printing is not executed and stopped (printing stop period (second period). In the present embodiment, in which the print head19is a line head, the printing period is a period in which a sheet Sh passes under the print head19. The printing stop period is a period other than the printing period in which the printing apparatus1is activated, e.g., the period from the completion of printing of one sheet Sh to the start of printing of the next sheet Sh, or the like.

As described usingFIG.12, in the printing period, the print data Dt is formed in a smaller size than in the printing stop period. In the printing stop period, the print data Dt is formed in a larger size than in the printing period. Thus, in the printing period, the amount of the print data Dt to be sent in units of packets is smaller. This makes it possible to omit unnecessary communication or communication with low priority between the control circuit board13and each individual element substrate15or lower the communication speed or the sending speed between them.

Incidentally, it suffices that the print data Dt is different in data size between the printing period and the printing stop period. As long as this condition is met, any of the above-described first to fourth modes (seeFIGS.7A to7D) may be assigned to the printing period and the printing stop period.

Referring back toFIGS.1B and4again, in the present embodiment, the processor131, which functions as a sending unit in the communication of the print data Dt, includes the first generation unit1311, the second generation unit1312, and the third generation unit1313. Also, the processor209, which functions as a reception unit, includes the first processing unit2091, the second processing unit2092, and the third processing unit2093.

First, the processor131, which functions as a sending unit, will be described. The first generation unit1311generates the data part D1forming part of the print data Dt. This data part D1includes the multiple information pieces inf11to inf15, and their data length (data size) is fixed. The first generation unit1311also adds dummy bits d(1) to d(4) to the pieces of synthesized data p1(9:1) to p4(9:1) included in the print data Dt to generate the information piece inf14(5 bytes) with the bit array illustrated inFIG.8B.

The second generation unit1312generates the data part D2forming the other part of the print data Dt. This data part D2is configured to be capable of containing the multiple additional information pieces inf21to inf26, and their data length is variable.

The third generation unit1313generates the print data Dt by combining the data part D1and the data part D2in a predetermined order. In the present embodiment, as illustrated inFIG.5, the print data Dt is generated in a layout in which the additional information pieces inf21to inf26are arranged between the information pieces inf11to inf14and the information piece inf15. The print data Dt thus generated is sent to the processor209.

Next, the processor209, which functions as a reception unit, will be described. The first processing unit2091identifies the information piece inf12in the data part D1, which is an additional information identifier, from the print data Dt received from the processor131. The second processing unit2092identifies the data part D2from the received print data Dt based on the content of the information piece inf12, and identifies the data part D1as well.

Here, as illustrated inFIG.5, the information piece inf12, which is an additional information identifier, is arranged before the additional information pieces inf21to inf26and indicates the presence or absence of each of the additional information pieces inf21, inf22, inf23, inf24, inf25, and inf26in the data part D2. This structure enables the first processing unit2091to properly identify the information piece inf12, which is an additional information identifier. The second processing unit2092is capable of properly identifying the data part D2based on the content of the information piece inf12, which is an additional information identifier, and also identifying the data part D1.

In addition, the second processing unit2092identifies the bits p1(9) to p1(1) illustrated inFIG.8Bfrom the identified data part D1and arranges the p1(9) to p1(1) in this order from higher to lower-order bits to generate the synthesized data p1(9:1). The second processing unit2092similarly generates the synthesized data p2(9:1), the synthesized data p3(9:1), and the synthesized data p4(9:1).

The third processing unit2093performs driving control for the printing operation itself among the driving control processes for the element substrate15based on the identified data part D1. The third processing unit2093also performs driving control related to the printing operation among the driving control processes for the element substrate15based on the identified data part D2.

A case where the print data Dt is sent in the first mode (seeFIG.7A) will be described as an example of the above “related driving control”.

In a specific example of the “related driving control”, the heating elements206heat the element substrate15based on the result of the detection by the temperature sensor205(the additional information pieces inf21and inf25are “0 (present)”). Moreover, the residue removal units204remove ink residues based on the results of the detection by the ejection sensors210(the additional information pieces inf24and inf26are “0 (present)”). Furthermore, analog signals and digital signals are output to the control circuit board13(the additional information pieces inf22and inf23are “0 (present)”).

In the present embodiment, the print data Dt is generated based on a print job input into the printing apparatus1from an external apparatus, and this print data Dt is sent to each element substrate15in the print head19by a serial transfer method. The print data Dt is generated by combining the data part D1with a fixed data length and the data part D2with a variable data length in a predetermined order.

One of the multiple information pieces inf11and so on included in the data part D1is the information piece inf12, which is an additional information identifier. This information piece inf12indicates the presence or absence of each of the multiple additional information pieces inf21and so on that can be included in the data part D2, and the data length of the data part D2is variable. The maximum value of the number of multiple additional information pieces inf21and so on that can be included in the data part D2is K (K is an integer of 1 or more). In this case, in one example, the information piece inf12, which is an additional information identifier, may be K-bit data (K=8 in the present embodiment).

The presence or absence of each of the multiple additional information pieces inf21and so on (or the information piece inf12indicating it) may be changed as the printing environment changes. This will now be described specifically. For example, a period after the printing apparatus1starts printing while conveying a sheet until the completion of the conveyance and the printing includes a printing period in which the print head19actually executes the printing and a printing stop period in which the printing is stopped. In the printing period, the amount of the print data Dt to be sent in units of packets is smaller than in the printing stop period. Thus, the information piece inf12, which is an additional information identifier, is changed when the data part D1is generated between the printing period and the printing stop period, and whether to generate each of the multiple additional information pieces inf21and so on is changed when the data part D2is generated between the two periods.

Incidentally, a case where the information piece inf14is subjected to division of 9-bit data and bit rearrangement has been exemplarily described above. Here, from the viewpoint of dividing bits, the contents described above can be applied to all information pieces forming the print data Dt. Also, an example in which the single most significant bit in each of the pieces of data p1to p4is gathered has been presented, but the bit organizing method is not limited to this one. For example, the single least significant bit or the single middle bit can be gathered, or multiple bits can be gathered instead of a single bit. It is to be noted that the contents described in this paragraph apply similarly to the second and subsequent embodiments below.

Second Embodiment

In the first embodiment, an example has been presented in which the single most significant bit in each of the pieces of data p1to p4is extracted, specifically, the single most significant bit in each of the pieces of data p1to p4is gathered in the 1-byte head data in the information piece inf14and sent. Unlike this, in a second embodiment, the extracted pieces of data are allocated to an additional information piece. Note that the following will mainly describe the contents different from the above, and description of the same contents as the above may be omitted.

FIG.13illustrates an example data structure of the print data Dt being data (serial data) to be sent in a single operation. The data part D2is configured to be capable of containing an additional information piece inf27in addition to the multiple additional information pieces inf21to inf26. The data length of the data part D2is variable.

FIG.14illustrates the content of the information piece inf12, which is an additional information identifier. In the present embodiment, the information piece inf12is 8-bit data. The seventh bit indicates the presence or absence of the additional information piece inf27. The eighth bit is dummy data (NULL) for maintaining the data size of the information piece inf12at eight bits. The data part D2includes the additional information piece inf27in a case where the seventh bit is “0”, and does not include the additional information piece inf27in a case where the seventh bit is “1”.

Incidentally, the additional information piece inf27is described as “DEFINITION DATA 2” inFIG.13since it forms definition data for defining the pulse waveforms of the driving signals for the printing elements201.

FIG.15Aillustrates the bit arrays of the information piece inf14and the additional information piece inf27in the case where the seventh bit in the information piece inf12(seeFIG.13), which is an additional information identifier, is “0”. As in the first embodiment, the bit configuration of the synthesized data p1(1:9) represents 9-bit data in which its bits are arranged from higher to lower-order bits starting from the most significant bit p1(9) in the order of p1(9), p1(8), p1(7), . . . . In other words, the bits are arranged starting from the least significant bit in the order of p1(1), p1(2), . . . , p1(9).

The bit array of the information piece inf14inFIG.15Ais partly the same as that in the first embodiment (seeFIG.8B). In the present embodiment, however, unlike the first embodiment, the bits d(1) to d(4), p1(9), p2(9), p3(9), and p4(9) are included in the additional information piece inf27. Also, the bits p1(1) to p1(8), p2(1) to p1(8), p3(1) to p3(8), and p4(1) to p4(8) are included in the information piece inf14.

The bit or bits to be included in the additional information piece inf27among the nine bits forming the synthesized data p1(9:1) and the number of such bits (one (i.e., one bit) in the example ofFIG.15A) are determined in advance. To generally describe this, a high-order bit array in the synthesized data having a predetermined bit length in the direction from its most significant bit toward the lower-order bits is included in the additional information piece. Specifically, in this example, a high-order bit array p1(9) in the synthesized data p1(9:1) having a length of one bit in the direction from its most significant bit p1(9) toward the lower-order bits is included in the additional information piece inf27. Regarding the number of bits to be included in the additional information piece inf27, the same applies to the other pieces of synthesized data, or the pieces of synthesized data p2(9:1) to p4(9:1).

Note that while one bit is employed as the predetermined bit length in the above, any single value that is two bits or more may be employed. For example, in a case of employing two bits, the bits p1(9) and p1(8) are included in the additional information piece inf27inFIG.15A.

Regarding the method of determining the length of the high-order bit array included in the additional information piece mentioned above (i.e., the predetermined bit length), this length is dependent on the maximum value available for each piece of synthesized data (e.g., the synthesized data p1(9:1) and so on). That is, as inFIG.16to be mentioned later, in a case where the length of the synthesized data p4is eight bits at most (the maximum value of p4is 255 or less), each of the bits p1(9), p2(9), p3(9), and p4(9) is always 0. Thus, the bit array with a length of one bit from the most significant bit is included in the additional information piece inf27, and the seventh bit inFIG.14(the presence or absence of the additional information piece inf27) is set to 1 to omit the additional information piece inf27. Such a configuration makes it possible to shorten the length of the print data Dt inFIG.13, and reduce the data amount of each piece of synthesized data to be actually sent as illustrated inFIG.15B.

Also, a configuration is conceivable in which, unlike the above, a low-order bit array in each piece of synthesized data having with a predetermined bit length in the direction from its least significant bit toward the higher-order bits is included in an additional information piece. Moreover, the configuration in which a high-order bit array having a predetermined bit length in the direction from the most significant bit toward the lower-order bits is included in an additional information piece and the configuration in which a low-order bit array having a predetermined bit length in the direction from the least significant bit toward the higher-order bits is included in an additional information piece may be combined.

Regarding the method of determining the length of the low-order bit array included in the additional information piece mentioned above (i.e., the predetermined bit length), this length is dependent on the resolution of each piece of synthesized data (e.g., the synthesized data p1(9:1) and so on). The resolution refers to the minimum unit amount by which the value of the synthesized data changes (such as intervals of 1 or 2). The resolution can also be called the minimum amount of change.

Specifically, as illustrated inFIG.18to be mentioned later, in a case where the resolution of the pieces of synthesized data p1to p4is 2, the least significant bits in the pieces of synthesized data p1to p4, specifically, the bits p1(1), p2(1), p3(1), and p4(1) are always 0. Thus, the bit arrays with a length of one bit from the least significant bits are included in the additional information piece inf27, and the seventh bit inFIG.14(the presence or absence of the additional information piece inf27) is set to 1 to omit the additional information piece inf27. Such a configuration makes it possible to shorten the length of the print data Dt inFIG.13, and reduce the data amount of each piece of synthesized data to be actually sent as illustrated inFIG.17B.

In the case where the seventh bit in the information piece inf12, which is an additional information identifier, is “0”, the bits p1(9) to p1(1) in the data p1are arranged in this order from higher to lower-order bits to form 9-bit synthesized data p1(9:1). The pieces of data p2to p4are configured similarly to the data p1.

FIG.15Billustrates the bit array of the information piece inf14in the case where the seventh bit in the information piece inf12, which is an additional information identifier, is “1”. As illustrated inFIG.15B, the additional information piece inf27is omitted in the case where the seventh bit in the information piece inf12, which is an additional information identifier, is “1”.

In this case, the most significant bit in the data p1is set to “0”, and the subsequent bits p1(8) to p1(1) are arranged in this order from higher to lower-order bits to form 9-bit data p1(9:1). The pieces of data p2to p4are configured similarly to the data p1.

FIG.16is a diagram similar toFIG.10in the first embodiment, and is a diagram for explaining the operation of generating the signal HEAT by the logic unit2076inFIG.4in the present embodiment. The vertical axis represents the count value of the counter901inFIG.9, and the horizontal axis represents time.

FIG.16indicates that the pieces of data p1to p4are all smaller than “0b1 0000 0000”. Here, the pieces of data p1to p4can each be expressed with eight bits. Thus, the data part in which their ninth bits are gathered can be deleted from the data array. That is,FIG.16illustrates a case where the seventh bit in the information piece inf12, which is an additional information identifier, can be set to “1”.

In a case where the ninth bit in the largest data p4among the pieces of data p1to p4is “0”, the seventh bit in the information piece inf12, which is an additional information identifier, is set to “1”, so that the ninth bits in the pieces of data p1to p4can be set to “0” without being included in the print data Dt.

The processor131, which functions as a sending unit, can determine whether to set the seventh bit in the information piece inf12to “0” or to “1” since the bit p4(9), which is the ninth bit in the data p4, is included in the print data Dt.

As in the first embodiment, the processor209, which functions as a reception unit, identifies the data parts D2and D1from the print data Dt received from the processor131. Also, as in the first embodiment, the first processing unit2091is capable of properly identifying the information piece inf12, which is an additional information identifier.

The second processing unit2092refers to the seventh bit in the information piece inf12, which is an additional information identifier, and executes an operation of generating the pieces of synthesized data p1(9:1), p2(9:1), p3(9:1), and p4(9:1) as described above according to the referred seventh bit.

The present embodiment is characterized in that the length of print data can be adjusted according to the pulse length of the signal HEAT. In a case where the duration of the signal HEAT is short, the cycle of the printing operation is shorter than in a case where the duration is long. Thus, the frequency of sending the print data Dt (referred to also as “transmission frequency”) is often desired to be higher. The configuration of the present embodiment is effective in such a case.

In the above, the single most significant bit in each of the pieces of data p1to p4(specifically, the bits p1(9), p2(9), p3(9), and p4(9)) is allocated to the additional information piece inf27. Note, however, that the present embodiment is not limited to this case. A similar advantageous effect can be achieved by applying the present embodiment to the two or more highest-order bits in each of the pieces of data p1to p4. Moreover, from the viewpoint of omitting sending of unnecessary data bits according to the data's set range (maximum value), it is possible to apply the present embodiment to all information pieces forming the print data Dt.

Third Embodiment

In the second embodiment, an example in which the single most significant bits in the pieces of data p1to p4are extracted, gathered, and sent in 1-byte data (additional information piece inf27) has been described. Unlike this, in a third embodiment, lower-order bits in the pieces of data p1to p4are extracted and allocated to an additional information piece. Note that the following will mainly describe the contents different from the foregoing embodiments, and description of the same contents as the above may be omitted.

The print data Dt being data (serial data) to be sent in a single operation is similar to that in the second embodiment (seeFIG.13). As in the second embodiment, the data part D2includes the additional information piece inf27in a case where the seventh bit in the information piece inf12is “0”, and does not include the additional information piece inf27in a case where the seventh bit is “1”.

FIG.17Aillustrates the bit arrays of the information piece inf14and the additional information piece inf27in the case where the seventh bit in the information piece inf12(seeFIG.13), which is an additional information identifier, is “0”. The bits d(1) to d(4), p1(1), p2(1), p3(1), and p4(1) are included in the additional information piece inf27. Moreover, the bits p1(2) to p1(9), p2(2) to p1(9), p3(2) to p3(9), and p4(2) to p4(9) are included in the information piece inf14.

In the case where the seventh bit in the information piece inf12, which is an additional information identifier, is “0”, the bits p1(9) to p1(1) in the data p1are arranged in this order from higher to lower-order bits to form 9-bit synthesized data p1(9:1). The pieces of data p2to p4are configured similarly to the data p1.

FIG.17Billustrates the bit array of the information piece inf14in the case where the seventh bit in the information piece inf12, which is an additional information identifier, is “1”. As illustrated inFIG.17B, the additional information piece inf27is omitted in the case where the seventh bit in the information piece inf12, which is an additional information identifier, is “1”.

In this case, the bits p1(8) to p1(1) in the data p1are arranged in this order from higher to lower-order bits with the least significant bit set to “0” to form 9-bit synthesized data p1(9:1). The pieces of data p2to p4are configured similarly to the data p1.

FIG.18is a diagram similar toFIG.10in the first embodiment, and is a diagram for explaining the operation of generating the signal HEAT by the logic unit2076inFIG.4in the present embodiment. The vertical axis represents the count value of the counter901inFIG.9, and the horizontal axis represents time.

FIG.18is a diagram illustrating the generation of the signal HEAT in the case where the seventh bit in the information piece inf12, which is an additional information identifier, is set to “1”. As mentioned earlier, the least significant bits in the pieces of data p1to p4are fixed to 0. InFIG.18, a 9-bit array with the least significant bit fixed to 0 is described as, for example, “P1(9:2) 0”.

To describe the values at a time t91inFIG.18, whileFIG.17Billustrates the print data Dt to be sent from which the additional information piece inf27has been omitted, as described earlier, these values indicate a situation where a fixed value of 0 is allocated to the least significant bit at this time. That is, each of these values is compared with the count value of the counter901, which represents the vertical axis, and the signal HEAT is toggled when the values match each other. Here, since the least significant bit is always 0, the resolution is half of the counter's resolution.

As in the first and second embodiments, the signal level of the signal HEAT changes at the times at which the signal CNT matches the pieces of data p1to p4. However, since the least significant bits in the pieces of data p1to p4are fixed to 0, the settable time resolution at which to change the signal level is two counts of the signal CNT.

As means for setting the seventh bit in the information piece inf12to “0” or to “1”, a table in which lengths of the signal HEAT (set values of the data p4) and set values of the seventh bit are associated with each other may be provided to the processor131, which functions as a sending unit. The processor131refers to this table and determines whether to set the seventh bit in the information piece inf12to “0” or to “1”. As an alternative approach, the element substrate15inFIG.4may be configured such that such a setting can be configured for the processor131through an input device not illustrated.

As in the first and second embodiments, the processor209, which functions as a reception unit, identifies the data parts D2and D1from the print data Dt received from the processor131.

Also, as in the first and second embodiments, the first processing unit2091is capable of properly identifying the information piece inf12, which is an additional information identifier.

The second processing unit2092refers to the seventh bit in the information piece inf12, which is an additional information identifier, and executes an operation of generating the pieces of synthesized data p1(9:1), p2(9:1), p3(9:1), and p4(9:1) as described above according to the referred seventh bit.

The present embodiment is characterized in that the resolution of the pulse time length of the signal HEAT can be adjusted. As the pulse length of the signal HEAT becomes longer, the amount of electric power to be input into the printing elements2011to201kwill be larger. However, the resolution of adjustment of the amount of electric power may be low as the amount of electric power increases. In such a case, applying the present embodiment can reduce the total amount of the print data Dt.

In the above, the single least significant bit in each of the pieces of data p1to p4(specifically, the bits p1(1), p2(1), p3(1), and p4(1)) is allocated to the additional information piece inf27. Note, however, that the present embodiment is not limited to this case. A similar advantageous effect can be achieved by applying the present embodiment to the two or more least significant bits in each of the pieces of data p1to p4. Moreover, from the viewpoint of avoiding sending of unnecessary data bits according to the data's set resolution, it is possible to apply the present embodiment to all information pieces forming the print data Dt.

OTHER EMBODIMENTS

In accordance with the present disclosure, print data can be efficiently sent in a printing apparatus having a variety of functions.

This application claims the benefit of Japanese Patent Application No. 2023-099177, filed Jun. 16, 2023, which is hereby incorporated by reference wherein in its entirety.