JP2009119606A - Ink-jet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve the introduction of the high speed detection of a non-ejection nozzle without losing the merit of a printer which is drive-controlled by a control signal from a PC. <P>SOLUTION: An ink-jet printer is disclosed in which a recording head 1 and a drive substrate 6 are mounted on a carriage 2 which is connected to the PC 110 so as to communicate with a PC 110 and is reciprocable in a main scanning direction, and the drive substrate 6 is controlled based on the control signal from the PC 110. A printer main body has a detecting means 8 that outputs a detection signal while capturing the shade of a detection ink droplet (a) ejected onto the optical axis of detection light. The drive substrate 6 on the carriage 2 has: an ejection control means that, in response to a detection start signal from the PC 110, outputs an ejection start signal for the detection ink droplet (a) for each nozzle according to a predetermined sequence; and a judging means that, if the detection signal is received from the detecting means 8 within a predetermined time after the output of the ejection start signal, judges that the ink droplet ejection is present. A communication means 9 is provided for transmitting the detection signal of the detecting means 8 to the judging means of the drive substrate 6 without contact. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ink jet printer, and more particularly, to an ink jet printer that can detect a non-ejection nozzle without losing the merit controlled by a personal computer.

  Conventionally, a general inkjet printer has a configuration as shown in FIG. Print data created by a personal computer (hereinafter referred to as a PC) 2001 is temporarily transferred (buffered) to a memory on an image processing board shared with a mechanical control board 1002 provided in the printer body of the inkjet printer 1001. . The print data transferred to the image processing board is transferred to the drive board 1003 in synchronization with the main scanning drive of the recording head. The mechanical control board 1002 performs all controls such as ink supply in addition to driving the main scanning driving unit 1004 and the sub-scanning driving unit 1005. Usually, a general-purpose interface such as a USB has a configuration in which these control commands and image data are mixed.

  In the case of a conventional general inkjet printer 1001 having such a configuration, the PC 2001 creates an image to be printed and transmits it according to the request of the printer 1001, and prints while the mechanical control board 1002 of the printer main body controls the main / sub scanning. The print data buffered in a timely manner at the right timing is appropriately taken out.

  In this case, the controller provided on the mechanical control board 1002 is dedicated to the processing of the printer and can cope with high speed. That is, when a configuration such as the non-ejection nozzle detection unit 1006 that detects ink droplets ejected from the recording head is introduced, the controller instructs the drive substrate 1003 to eject the target nozzle, and the ink droplets are ejected from the nozzles. The non-ejection nozzle detection unit 1006 detects whether or not the nozzle has actually ejected. In this case, the time from discharge to detection is on the order of μsec, and the same high speed is required for the discharge timing. Conventionally, the controller of the mechanical control board 1002 performs these controls.

  On the other hand, recently, as shown in FIG. 13, an ink jet printer system in which the PC 2010 directly controls the drive substrate and main / sub scanning of the ink jet printer 1010 has appeared. The background of this configuration is the high speed of performing print data development with PC software, the demand for increased print data transfer speed due to the increase in the number of heads (number of nozzles), and the creation of a control board for each printer. There is an advantage that development man-hours can be reduced.

  The configuration of the inkjet printer system shown in FIG. 13 is characterized by an interface between an interface that transmits print data to the drive substrate 1011 of the printer 1010 and another mechanical control system such as the main scanning drive unit 1012 and the sub-scanning drive unit 1013. It is that it is divided. In this case, the interface I / F-1 for transferring print data from the PC 2010 to the drive board 1011 of the printer 1010 uses a high-speed serial transfer system such as optical communication or LVDS (low voltage differential signaling), and the drive system For interface I / F-3, 4, and 5, it is common to use a low-speed, general-purpose interface such as RS-232C.

Here, when the printer main body does not have an image buffer, a print data buffer memory substrate 2011 in which head data is expanded is required on the PC 2010 side. These are generally connected to the mother board in the PC 2010 by a PCI bus or the like. Signals that require high-speed synchronization such as print start timing (encoder and print start timing) enter the memory board 2011.
Japanese Patent Laid-Open No. 10-119307

  Here, a problem arises when non-ejection nozzles are detected in the inkjet printer system shown in FIG. In other words, since software on the PC 2010 side normally uses an OS (operation system), it is difficult to react to external signals in the order of μsec. The printer 1010 and the PC 2011 perform a high-speed sequence such as sending an ejection start signal to the drive substrate 1011, detecting a detection signal from the non-ejection detector, judging non-ejection, and controlling ejection of the next nozzle. It is virtually impossible to do. In that case, a controller board for detecting a non-ejection nozzle that gives an instruction to the drive board 1011 on the printer 1010 side is newly required, and the PC 2010 must be configured to communicate with the controller board.

  In addition, in order to communicate between the drive board 1011 moving along the main scanning direction on the carriage and the PC 2010, as described above, a serial communication system such as optical communication or LVDS is often used. It is difficult to insert data communication and a different discharge control signal, and a new signal line is required. However, it is not easy to install a new signal line.

  As described above, in the inkjet printer having the configuration of FIG. 13 which has become the mainstream recently, the introduction of the configuration for detecting the non-ejection nozzles requires a controller board substantially similar to the configuration shown in FIG. Therefore, the merit of replacing the configuration as shown in FIG. 13 is lost. Therefore, in fact, such an inkjet printer system does not introduce non-ejection nozzle detection.

  Therefore, the present invention provides an ink jet printer and an ink jet printer system that can introduce non-ejection nozzle detection having high speed without losing the advantages of an ink jet printer that is driven and controlled based on a control signal from a PC. This is the issue.

  Other problems of the present invention will become apparent from the following description.

  The above problems are solved by the following inventions.

  According to a first aspect of the present invention, there is provided a recording head for ejecting ink droplets from nozzles on a carriage which is connected to a personal computer so as to be able to send and receive signals and which can reciprocate along the main scanning direction of the printer body. An ink jet printer that includes a driving substrate to be driven and controls the driving substrate based on a control signal transmitted from the personal computer, and a light emitting element that emits detection light to the printer body and the detection light A detecting means for outputting a detection signal when the light receiving element captures a shadow of a detection ink droplet ejected on the optical axis of the detection light, In response to a detection start signal from the personal computer, the drive board receives the detection input for each nozzle according to a predetermined sequence. A discharge control unit that outputs a droplet discharge start signal, and a determination that determines that ink droplets are discharged from a nozzle when a detection signal is received from the detection unit within a predetermined time after the discharge start signal is output And a communication unit that transmits a detection signal from the detection unit to the determination unit provided on the drive board in a non-contact manner.

  According to a second aspect of the present invention, there is provided a recording head for ejecting ink droplets from nozzles on a carriage which is connected to a personal computer so as to be able to transmit and receive signals and which can reciprocate along the main scanning direction of the printer body. An ink jet printer that includes a driving substrate to be driven and controls the driving substrate based on a control signal transmitted from the personal computer, and a light emitting element that emits detection light to the printer body and the detection light Detecting means for outputting a detection signal when the light receiving element catches a shadow of the detection ink droplet ejected on the optical axis of the detection light, and for detection for each nozzle. An ejection control means for outputting an ink droplet ejection start signal to the driving substrate; and after the ejection of the detection ink droplet, the detection means within a predetermined time. A communication unit that transmits the discharge start signal from the discharge control unit to the drive substrate in a non-contact manner. The drive substrate on the carriage receives a detection start signal from the personal computer and then receives a detection ink droplet discharge start signal from the discharge control means via the communication means. An ink jet printer that discharges ink droplets for detection from nozzles according to a sequence.

  A third aspect of the invention is the ink jet printer according to the first or second aspect, wherein the detection signal is a signal created based on a signal obtained from the shadow of the ink droplet.

  A fourth aspect of the present invention is the ink jet printer according to the first, second or third aspect, wherein the communication means is optical communication using a light emitting element and a light receiving element.

  The invention according to claim 5 is the ink jet printer according to claim 4, wherein the light emitting element of the communication means emits infrared light.

  A sixth aspect of the present invention is the ink jet printer according to the fourth or fifth aspect, wherein a duty ratio of a light emission pulse of a detection signal by the light emitting element of the communication means is 10% or less.

  According to a seventh aspect of the present invention, of the light emission amount of the light emitting element of the communication means and the amplification factor of the light receiving element, according to the distance between the light emitting element and the light receiving element of the communication means or the shift amount of the optical axis. 7. The ink jet printer according to claim 4, further comprising changing means for changing at least one of them.

  According to an eighth aspect of the present invention, a plurality of sets of the detection means are arranged so that a plurality of nozzle arrays can be detected simultaneously, and a logical product of the output signals of the plurality of detection means is obtained and merged output to the determination means. The inkjet printer according to claim 1, wherein the inkjet printer is a printer.

  An invention according to claim 9 is an ink jet comprising the ink jet printer according to any one of claims 1 to 8 and a personal computer connected to the ink jet printer so as to be able to transmit and receive signals. It is a printer system.

  According to the present invention, there is provided a sink jet printer and an ink jet printer system capable of introducing non-ejection nozzle detection having high speed without losing the merit of an ink jet printer driven and controlled based on a control signal from a PC. can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing the main part of an ink jet printer according to the first invention, and FIG. 2 is a block diagram showing the entire structure of an ink jet printer system having the ink jet printer shown in FIG.

  In the figure, 100 is an ink jet printer system, 101 is an ink jet printer, and 110 is a PC (personal computer) for controlling the operation of the ink jet printer 101.

  In the ink jet printer 101, reference numeral 1 denotes a recording head. Although FIG. 1 illustrates an example in which the four recording heads 1A to 1D are arranged in a staggered manner, the number of recording heads is not particularly limited. In FIG. 2, only one recording head is shown as a representative. All the recording heads 1 </ b> A to 1 </ b> D are mounted on a common carriage 2. The carriage 2 is slidably provided along a guide rail 3 extending along the main scanning direction X in FIG. 1, and reciprocates along the main scanning direction X by driving of the main scanning driving unit 10 shown in FIG. .

  Each of the recording heads 1A to 1D ejects ink droplets in the downward direction in the figure according to the print data while the carriage 2 moves in the main scanning, and the main scanning movement of the carriage 2 driven by the main scanning driving unit 10 is shown in FIG. A desired image is recorded on a recording medium (not shown) in cooperation with the sub-scanning movement of the recording medium by driving the sub-scanning driving unit 11 shown. The main scanning drive unit 10 and the sub-scanning drive unit 11 receive control signals from the PC 110 via low-speed communication interfaces (I / F-L) 23 and 24 such as RS-232C, respectively. Operation controlled.

  As shown in FIG. 1, an encoder sensor 4 is provided on the carriage 2. The encoder sensor 4 generates a pulse signal by reading the scale on the linear encoder 5 installed along the main scanning direction X, and based on this pulse signal, the position of the carriage 2, that is, the recording heads 1A to 1D. Position information in the main scanning direction X can be acquired.

  In the ink jet printer 101, as shown in FIG. 2, a drive substrate 6 that drives the recording head 1 is mounted on the carriage 2 for each recording head 1. The drive substrate 6 includes a driver 61 that applies a drive signal for ejection to the recording head 1 and a controller 62 that is a detection control unit that performs control for detecting a non-ejection nozzle.

  The drive substrate 6 is connected to the PC 110 through a high-speed communication interface (I / F-H) 21 such as LVDS or optical communication so that signals can be transmitted and received. Reference numeral 7 in FIG. 2 denotes a buffer memory provided in the ink jet printer 101, which temporarily stores data signals (Data) such as print data sent from the PC 110. When performing image recording based on the print data, the print data expanded in the PC 110 is temporarily stored in the buffer memory 7 and is added to the positional information acquired from the encoder sensor 4 together with the transfer synchronization signal (Cont). In response, a discharge start signal (Trig) for printing is transmitted to the driver 61 of the drive substrate 6.

  Further, since the controller 62 is in the drive board 6, signals can be transmitted to and received from the PC 110 through the interface (I / F-H) 21. The controller 62 receives a start command for non-ejection nozzle detection from the PC 110 and transmits a non-ejection nozzle detection result to the PC 110, and also detects a ejection start signal (Def-Trig) for detection to the driver 62. Is supposed to send.

  As described above, in the first aspect of the invention, the controller 62 for detecting the non-ejection nozzle is provided in the drive board 6, so that transmission / reception of signals to / from the PC 110 is performed to / from the drive board 6. Therefore, the interface (I / F-H) 21 can be used as it is.

  FIG. 3 shows details of the controller 62. A discharge control unit 621 receives a start command from the PC 110 and transmits a discharge start signal (Def-Trig) for detection to the driver 61 according to a predetermined sequence. Reference numeral 622 denotes a determination unit that determines whether or not the nozzle is a non-discharge nozzle, and the determination result is stored in a memory (not shown) as a non-discharge nozzle detection result.

  The non-ejection nozzle detection device 8 is disposed in the printer main body in the inkjet printer 101 so as not to move. The non-ejection nozzle detection device 8 is positioned so as to face the lower side when the carriage 2 moves to a non-printing position that is off a recording medium (not shown), and a light emitting element 81 made of an LED, a laser, or the like. And a light receiving element 82 made of a photodiode or the like, an ink tray 83 that receives the ink droplet a ejected at the time of detection, and a detection unit 84 that outputs a detection signal when the ink droplet a is detected. In addition, although not shown, it has driving means for turning on / off the light emitting element 81 in response to an instruction from the PC 110.

  The light emitting element 81 is ON / OFF controlled by the PC 110 via, for example, an interface (I / F-L) 22 for low speed communication such as RS-232C and is discharged from each nozzle of the recording head 1 by being turned on. The detection light L for detecting the passage of the ink droplet a is emitted, and the light receiving element 82 receives the detection light L and outputs a light amount signal to the detection unit 84. The light emitting element 81 and the light receiving element 82 are opposed to each other with a distance that can sandwich the nozzle row of the recording head 1, and the optical axis of the detection light L is parallel to the nozzle surface of the recording head 1. Thus, the height position along the ejection direction of the ink droplet a is arranged to be lower than the position of the nozzle surface. Thus, when the nozzle of the recording head 1 is positioned on the detection light L, the traveling path of the ink droplet a ejected from the nozzle intersects with the detection light L. Therefore, when the driver 61 is driven to eject the ink droplet a toward the detection light L from any of the nozzles located on the detection light L, the ink droplet a passes through the detection light L and reaches the ink tray 83. Land. The light receiving element 82 captures a shadow when the ink droplet a passes the detection light L, and sends a change in the light amount signal at that time to the detection unit 84.

  As shown in FIG. 4, the detection unit 84 includes a current amplification unit 841, an AC amplification unit 842, a middle band filter 843, a low band filter 844, a comparator 845, and a filter pulse adjustment unit 846. The light amount signal from the light receiving element 82 is first DC amplified by the current amplifying unit 841, and then the fluctuation amount of the light amount signal is amplified by the AC amplifying unit 842. The output signal from the AC amplifying unit 842 is input to the comparator 845 after noise is removed via the mid-pass filter 843. On the other hand, the output signal from the mid-pass filter 843 is also input to the low-pass filter 844. The low pass filter 844 generates a reference signal from the output signal from the mid pass filter 843 and inputs the reference signal to the comparator 845. The comparator 845 compares the output signal input through the mid-pass filter 843 with the reference signal generated by the low-pass filter 844, and outputs a signal when the output signal exceeds the reference signal. The signal output from the comparator 845 is subjected to filter and pulse width adjustment on the output signal from the comparator 845 by the filter pulse adjustment unit 846 and output as a final detection signal (Defect-out).

  FIG. 5 is a timing chart showing the relationship among ejection signals for detecting non-ejection nozzles, output signals from the light receiving element 82, and detection signals (Defect-out). Here, in response to a discharge start signal for detection (Def-Trig), a discharge signal for non-discharge nozzle detection is given to the driver 61 so as to discharge three ink droplets a from one nozzle in succession. The droplets are made into a group of ink droplets so that they can be easily detected as a lump of large ink droplets.

  When the ink droplet group is normally ejected from the nozzle by giving such an ejection signal to the driver 61, the amount of light temporarily decreases as the ink droplet group passes through the optical axis of the detection light L. The detection unit 84 outputs a detection signal (Defect-out) with the passage of the ink droplet group when the decrease in the output signal of the light receiving element 82 exceeds the reference signal (Vref).

  This detection signal (Defect-out) is preferably a signal created based on a signal obtained from the shadow of the ink droplet a. The signal generated based on the signal obtained from the shadow of the ink droplet a is a signal itself for determining whether or not the shadow of the ink droplet a is captured. Thereby, the subsequent control system can directly input the detection signal, and there is an effect that high-speed processing and signal processing can be easily performed.

  A detection signal (Defect-out) output from the detection unit 84 is input to the determination unit 622 of the controller 62 in the drive substrate 6 on the carriage 2 via the communication unit 9. The determination unit 622 counts a predetermined time by a counting unit (not shown) from the time when the discharge control unit 621 outputs the discharge start signal (Def-Trig), and detects it until the predetermined time elapses. When a detection signal (Defect-out) indicating the passage of the ink droplet a is input from the unit 84, it is determined that the ink droplet a is ejected from the nozzle, that is, a normal nozzle, and a predetermined time has elapsed. When the detection signal (Defect-out) is not input from the detection unit 84, it is determined that no ink droplet a is ejected from the nozzle, that is, it is a non-ejection nozzle. The determination result is stored in the determination unit 622 and retrieved via the interface (I / F-L) 22 in accordance with a request from the PC 110.

  The communication means 9 for transmitting a detection signal (Defect-out) from the detection unit 84 to the determination unit 622 of the controller 62 includes, as shown in FIGS. 1 and 2, a light emitting element 91 made of an LED, a laser, or the like, a photodiode, or the like. And a light receiving element 92. Like the non-ejection nozzle detection device 8, the light emitting element 91 is provided so as not to move in the printer body, and the light receiving element 92 is provided on the carriage 2. That is, when a detection signal (Defect-out) is output from the detection unit 8, the communication unit 9 turns on the light emitting element 92 according to the detection signal (Defect-out), and receives the emitted light on the carriage 2 side. When the element 92 receives light, the detection signal (defect-out) from the detection unit 84 is transmitted to the controller 62 in the drive substrate 6 on the carriage 2 in a non-contact manner.

  In this way, the communication means 9 performs non-contact communication between the controller 62 on the carriage 2 and the non-ejection nozzle detection device 8 on the printer main body side, so that a signal for transmitting and receiving signals to and from the PC 110 is used. It is not necessary to add a new signal line for detecting a non-ejection nozzle to the line. Even when a signal line is added, the carriage 2 at the time of non-ejection nozzle detection needs only to have a movement width that allows the recording head 1 to be detected to be positioned on the detection light L, whereas at the time of printing. The carriage 2 moves in the main scanning over a longer width than the printing area. Therefore, when the non-ejection nozzle detection device 8 is connected by a signal line, a long signal line is useless for detection of the non-ejection nozzle. Must be used. However, by using the non-contact communication means 9 in this way, it is not necessary to use an unnecessarily long signal line.

  The DUTY ratio of the light emission pulse of the light emitting element 91 that emits light by this detection signal (Defect-out), that is, the ratio of the light emission time t1 shown in FIG. 5 to the non-light emission time t2 is preferably 10% or less. As a result, the current to the light emitting element 91 can be increased, the communication distance can be extended by increasing the amount of light emission, and the reliability of communication is increased. This can be easily realized by changing the detection signal (defect-out) output from the detection unit 84 through the filter pulse adjustment 846 and changing the filter and the pulse width.

  Further, it is preferable that the communication means 9 performs infrared communication using infrared light because the influence of malfunction due to disturbance light can be reduced.

  By the way, the light emitting element 91 in the communication means 9 is fixed to the printer main body, while the light receiving means 92 is provided in the carriage 2, so that when a plurality of recording heads are mounted on the carriage 2 as shown in FIG. The position of the carriage 2 in the main scanning direction X differs depending on the position of the recording head 1 that is the detection target of the nozzle. Accordingly, the distance between the light emitting element 91 and the light receiving element 92 is different, and the optical axis is shifted. For this reason, the communication means 9 changes either the light emission amount of the light emitting element 91 or the amplification factor of the light receiving element 92 according to the distance between the light emitting element 91 and the light receiving element 92 or the amount of deviation of the optical axis. It is preferable to have changing means (not shown).

  That is, when the distance between the light emitting element 91 and the light receiving element 92 is large or the light receiving element 92 is located at a position shifted from the optical axis of the emitted light of the light emitting element 91, the light emission amount of the light emitting element 91 is increased, The amplification factor of the light amount signal captured by the light receiving element 92 is increased. As a result, regardless of the position of the carriage 2, the light receiving element 92 can reliably receive the detection signal (Defect-out) from the detection unit 84.

  The change in the light emission amount of the light emitting element 91 and the change in the amplification factor of the light receiving element 92 can be made in two steps, small and large, or small, medium and large, depending on the distance and angle between the light emitting element 91 and the light receiving element 92. It is possible to carry out by arbitrarily setting, for example, changing to three stages. In addition, a light emitting element having a small amount of light emission and a light emitting element having a large amount of light emission are provided in advance as the light emitting element 91. In accordance with the distance and angle between the light emitting element 91 and the light receiving element 92, a plurality of light emitting elements with different light emission amounts and a plurality of light receiving circuits with different amplification factors are provided. It is also possible to automatically select and use these. The relative positions of the light emitting element 91 and the light receiving element 92 can be obtained from the positional information of the carriage 2 acquired by the encoder sensor 4.

  Next, an example of an operation sequence for detecting a non-ejection nozzle in the ink jet printer system 1 will be described with reference to FIG.

  When the PC 110 instructs the detection unit 84 of the non-ejection nozzle detection device 8 to turn on the light emitting element 81, the detection unit 84 starts light emission of the light emitting element 81, and detection light is emitted between the light emitting element 81 and the light receiving element 82. L is formed (S1). The light emitting element 81 may be constantly lit without being controlled to be lit every time the non-ejection nozzle is detected by the PC 110.

  Next, the PC 110 moves the carriage 2 to align the nozzle row to be detected with the optical axis of the detection light L, and then sends a non-ejection nozzle detection start command (Def-Sens) to the controller 62 of the drive substrate 6. -Strt) is transmitted (S2).

  In response to this, the controller 62 returns a return signal (Ret) to the PC 110 (S3), and the discharge control unit 621 of the controller 62 performs a series of operations for detecting non-discharge nozzles preset in the controller 62 itself. Start (S4).

  In the non-ejection nozzle detection operation, first, preliminary ejection for forcibly ejecting predetermined (Ny) ink droplets from all nozzles is performed, and the states of all the nozzles are made uniform. Thereafter, the nozzle number n to be discharged is set to n = 1, and the driver 61 is set to No. A discharge start signal (Def-Trig) for continuously discharging a plurality of (Ns) ink droplets from one nozzle is output.

  When the ejected ink droplet passes the detection light L of the non-ejection nozzle detection device 8, the detection unit 84 of the non-ejection nozzle detection device 8 outputs a detection signal (defect-out) indicating that the ink droplet has passed. The light emitting element 91 of the communication unit 9 emits light when a detection signal (Defect-out) is output from the detection unit 84, and the light receiving element 92 on the carriage 2 side receives the emitted light and the determination unit 622 of the controller 62. To enter.

  When the detection signal (Defect-out) is input via the communication unit 9 within a predetermined time after the discharge control unit 621 outputs the discharge start signal (Def-Trig), the determination unit 622 determines No. It is determined that one nozzle is normal, and the result is stored.

  Similarly, no. 2 nozzles, no. The discharge and determination from the three nozzles are sequentially repeated, and the determination unit 622 stores the determination result of each nozzle.

  Thereafter, the controller 62 of the drive substrate 6 performs non-ejection nozzle detection for all nozzles of all recording heads, and then receives a command (Def-Reslt-Recv) requesting acquisition of a detection result from the PC 110 (S5). ), The result of determination at the time of detecting a non-ejection nozzle performed immediately before receiving the command is returned to the PC 110 (S6).

  Such a non-ejection nozzle detection operation is controlled by the controller 62 of the drive substrate 6 without interposing the PC 110, and the result is a detection signal (defect) from the non-ejection nozzle detection device 8 without interposing the PC 110. -out), the controller 62 in the drive substrate 6 makes a determination, and therefore, the inkjet printer 101 and the PC 110 only start the non-ejection nozzle detection and send and receive commands for obtaining the detection results. There is no need to add a communication line that requires high-speed synchronization. It can be added as a command specification to a normal serial communication line to the drive board for head parameter setting such as head voltage and drive waveform setting. Accordingly, the non-ejection nozzle is detected without requiring a new signal line for non-ejection nozzle detection between the driving substrate 6 that is driven and controlled based on the control signal from the PC 110 and the PC 110. be able to.

  Originally, a drive substrate for driving the recording head is necessary and is mounted on the carriage of the printer main body. In the present invention, by simply changing the configuration in the drive board, a new board is created and additionally installed for detecting a non-ejection nozzle that originally needs high speed, and a signal is newly connected to the PC. It can be executed only by command control from the PC, and it can be said that the range of use has expanded.

  FIG. 7 is a block diagram of an inkjet printer system 200 having the inkjet printer 102 according to the second invention. Since the parts having the same reference numerals as those in FIG. 2 are parts having the same configuration, detailed description thereof will be omitted.

  The ink jet printer 102 according to this aspect includes a command analysis unit 63 on the drive substrate 6 mounted on the carriage 2 (see FIG. 1). When the command analysis unit 63 receives a detection mode setting command (Def-Mode-Set) for non-ejection nozzle detection operation transmitted from the PC 110 via the interface (I / F-H) 21, the command analysis unit 63 sends a command to the driver 61. In accordance with a predetermined sequence determined in advance. The apparatus waits to eject ink droplets a from one nozzle. Further, when a detection mode cancel command (Def-Mode-Ret) is received, the operation mode for detecting a non-ejection nozzle is canceled.

  Further, the non-ejection nozzle detection device 8 in this aspect includes a detection board 85 with a determination function, and the light amount signal of the light receiving element 82 is input to the detection board 85 with a determination function. Similar to the detection unit 84 shown in FIG. 2, the detection board 85 with a determination function is disposed so as to be immovable in the printer main body.

  FIG. 8 shows details of the detection board 85 with a judgment function. The detection substrate 85 with a determination function includes a detection unit 851, and a discharge control unit 852 and a determination unit 853 that are controllers having the same functions as the controller 62 illustrated in FIG.

  The detection unit 851 receives the light amount signal of the light receiving element 82 and outputs a detection signal (Defect-out) when the ink droplet a passes the detection light L. The specific configuration of the detection unit 851 is the same as that in FIG.

  The discharge controller 852 outputs a discharge start signal (Def-Trig) for detection to the driver 61 of the drive substrate 6 in accordance with a predetermined timing set in advance. In this embodiment, the discharge start signal (Def-Trig) is a lighting signal for causing the light emitting element 91 of the communication means 9 to emit light. The discharge start signal (Def-Trig) is also output to the determination unit 853 at the same time.

  The determination unit 853 receives the detection signal (Defect-out) from the detection unit 851 and the discharge start signal (Def-Trig) from the discharge control unit 852 in the same manner as the determination unit 622 shown in FIG. Determine the presence or absence. The determination result is stored in the determination unit 853 as a non-ejection nozzle detection result, and is extracted according to a request from the PC 110.

  In this embodiment, the communication means 9 sends the detection discharge start signal (Def-Trig) output from the detection unit 85 with a determination function to the drive substrate 6 via the light emitting element 91 and the light receiving element 92 on the carriage 2 side. Transmit to the driver 61. Accordingly, the driver 61 receives the discharge start signal (Def-Trig) from the detection substrate 85 with a determination function and discharges the ink droplet a.

  Also in this aspect, similarly to the first invention, the non-ejection nozzle detection operation can be performed without interposing the PC 110. Therefore, the non-ejection nozzle detection start or detection is performed between the inkjet printer 102 and the PC 110. It is only necessary to send and receive commands for obtaining results, and there is no need to add a new signal line that requires high-speed synchronization. Accordingly, the non-ejection nozzle is detected without requiring a new signal line for non-ejection nozzle detection between the driving substrate 6 that is driven and controlled based on the control signal from the PC 110 and the PC 110. be able to.

  By the way, in the first and second present inventions, not only one non-ejection nozzle detection device that detects non-ejection nozzles of a plurality of recording heads 1, but also a plurality of recording heads by a plurality of non-ejection nozzle detection devices. One non-ejection nozzle detection can be processed simultaneously.

  FIG. 9 is a configuration diagram illustrating an example of a non-ejection nozzle detection apparatus that can simultaneously process non-ejection nozzle detection of four recording heads.

  The light emitting elements 81A to 81D, the light receiving elements 82A to 82D, and the detectors 86A to 86D are arranged corresponding to different recording heads. In addition, since the specific structure of each detection part 86A-86D is the same as FIG. 4, description is abbreviate | omitted.

  In this non-ejection nozzle detection device 800, when the ink droplets for detection are simultaneously ejected from the nozzles of the same nozzle number of each recording head and the shadow of the ink droplets is captured from the nozzles of the corresponding recording heads, Detection signals A to D are output to the detection circuit unit 87 from 86A to 86D, respectively. The detection circuit unit 87 outputs one detection signal (Defect-out) when the detection signals A to D are input from all the detection units 86A to 86D.

  FIG. 10 is a configuration diagram illustrating an example of the detection circuit unit 87. Reference numerals 87A to 87D denote AND circuit boards provided corresponding to the detection units 86A to 86D, and are provided with AND circuits 871A to 871D, respectively. The AND circuit boards 87A to 87D are cascade-connected so that the outputs of the AND circuits 871B to 871D are input to the adjacent AND circuits 871A to 871C.

  By cascade connection, non-ejection nozzle detection can be performed simultaneously on a plurality of heads, and the detection time can be shortened.

  Here, the detection signal D from the detector 86D is input to the AND circuit 871D of the AND circuit board 87D. One of the AND circuits 871D is pulled up, and when the detection signal D is input, the AND circuit 871D outputs a signal to the AND circuit 871C of the adjacent AND circuit board 87C. When the AND circuit 871C receives the input of the detection signal C and the signal input from the AND circuit board 87D, the AND circuit board 87C outputs a signal to the AND circuit 871B of the adjacent AND circuit board 87B. When the AND circuit 871B receives the detection signal B and the signal input from the AND circuit board 87C, the AND circuit board 87B outputs a signal to the AND circuit 871A of the adjacent AND circuit board 87A. The AND circuit board 87A outputs a detection signal (Defect-out) when the AND circuit 871A receives a detection signal A and a signal input from the AND circuit board 87B. The detection signal (Defect-out) output from the AND circuit board 87A becomes an output signal from the detection circuit unit 87. In the mode shown in FIG. 2, the detection signal (Defect-out) becomes a signal for causing the light emitting element 91 of the communication means 9 to emit light. 7 and 8, the output signal is output to the determination unit 853 and is used to determine whether there is a non-ejection nozzle.

  Each of the AND circuit boards 87A to 87D is a board (parent board) that outputs a final detection signal (Defect-out) or a board (child board) that outputs a signal to an adjacent AND circuit board. DIP switches 872A to 872D, which are identification means for identifying the above, are provided.

  FIG. 11 is a timing chart when the non-ejection nozzle detection apparatus 800 detects non-ejection nozzles. When ejection of all ink droplets is detected from the nozzles n-1 and n + 1 having the same nozzle number of each recording head, one detection signal (Defect-out) is output from the AND circuit board 87A. However, for example, in the case of detecting the nozzle n, if there is a non-ejection nozzle that does not output the detection signal C only from the detection unit 86C corresponding to the AND circuit board 87C, the detection signal ( Defect-out) is not output. That is, it can be detected that there is a recording head in which a non-ejection nozzle is generated in the nozzle n. The recording head can be specified by detecting only the nozzles n of each recording head individually after that.

The perspective view which shows the principal part of the inkjet printer which concerns on this invention The block diagram which shows the structure of the whole inkjet printer system which has an inkjet printer shown in FIG. Block diagram showing details of the controller shown in FIG. The block diagram which shows the detail of the detection part of the non-ejection nozzle detection device Timing chart showing relationship between ejection signal for non-ejection detection, output signal of light receiving element, and detection signal (Defect-out) The figure explaining an example of the operation sequence for non-ejection nozzle detection Block diagram of an inkjet printer system having an inkjet printer according to another aspect The block diagram which shows the detail of the detection board with a judgment function shown in FIG. The block diagram which shows an example of the non-ejection nozzle detection apparatus which enabled it to process the non-ejection nozzle detection of four recording heads simultaneously FIG. 9 is a block diagram showing an example of the detection circuit unit shown in FIG. Timing chart in the case of detecting a non-ejection nozzle by the non-ejection nozzle detection device shown in FIGS. Block diagram showing a conventional inkjet printer Block diagram showing a conventional inkjet printer

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A-1D: Recording head 2: Carriage 3: Guide rail 4: Encoder sensor 5: Linear encoder 6: Drive board 61: Driver 62: Controller
621: Discharge control unit
622: Determination unit 63: Command analysis unit 7: Buffer memory 8: Non-ejecting nozzle detection device 81: Light emitting element 82: Light receiving element 83: Ink tray 84: Detection unit 85: Detection board with determination function 86A to 86D: Detection unit 87 : Detection circuit unit 9: Communication means 91: Light emitting element 92: Light receiving element 10: Main scanning driving unit 11: Sub scanning driving unit 21-24: Interface 100, 200: Inkjet printer system 101, 102: Inkjet printer 110: Personal computer (PC)

Claims (9)

A recording head for ejecting ink droplets from nozzles and a driving substrate for driving the recording head are mounted on a carriage that is connected to a personal computer so as to be able to transmit and receive signals and can reciprocate in the main scanning direction of the printer body. , An inkjet printer in which the drive substrate is controlled based on a control signal transmitted from the personal computer,
The printer main body has a light emitting element that emits detection light and a light receiving element that receives the detection light, and the light receiving element captures a shadow of a detection ink droplet ejected on the optical axis of the detection light. A detection means for outputting a detection signal in case,
A discharge control means for receiving a detection start signal from the personal computer on the carriage on the carriage and outputting a discharge start signal of the detection ink droplet for each nozzle according to a predetermined sequence; and A determination means for determining that there is ejection of an ink droplet from the nozzle when a detection signal from the detection means is received within a predetermined time after the output;
An ink jet printer, comprising: a communication unit that transmits a detection signal from the detection unit to the determination unit provided on the drive board in a non-contact manner. A recording head for ejecting ink droplets from nozzles and a driving substrate for driving the recording head are mounted on a carriage that is connected to a personal computer so as to be able to transmit and receive signals and can reciprocate in the main scanning direction of the printer body. , An inkjet printer in which the drive substrate is controlled based on a control signal transmitted from the personal computer,
The printer main body has a light emitting element that emits detection light and a light receiving element that receives the detection light, and the light receiving element captures a shadow of a detection ink droplet ejected on the optical axis of the detection light. A detection means for outputting a detection signal in each case, an ejection control means for outputting an ejection start signal for the detection ink droplet for each nozzle to the drive substrate, and within a predetermined time after ejection of the detection ink droplet A determination unit that determines that there is ejection of an ink droplet from a nozzle when receiving a detection signal from the detection unit;
Communication means for transmitting the discharge start signal from the discharge control means to the drive substrate in a non-contact manner;
The drive board on the carriage follows a predetermined sequence when it receives a discharge start signal of a detection ink droplet from the discharge control means via the communication means after receiving a detection start signal from the personal computer. An ink jet printer which discharges ink droplets for detection from a nozzle.   The ink jet printer according to claim 1, wherein the detection signal is a signal created based on a signal obtained from a shadow of the ink droplet.   4. The ink jet printer according to claim 1, wherein the communication means is optical communication using a light emitting element and a light receiving element.   5. The ink jet printer according to claim 4, wherein the light emitting element of the communication means emits infrared light.   6. The ink jet printer according to claim 4, wherein a DUTY ratio of a light emission pulse of a detection signal by the light emitting element of the communication means is 10% or less.   Change means for changing at least one of the light emission amount of the light emitting element of the communication means and the amplification factor of the light receiving element according to an interval between the light emitting element and the light receiving element of the communication means or an optical axis shift amount. The ink jet printer according to claim 4, wherein the ink jet printer is provided.   A plurality of sets of the detection means are arranged so that a plurality of nozzle rows can be detected simultaneously, and a logical product of output signals of the plurality of sets of detection means is obtained and output to the determination means. The inkjet printer in any one of 1-7. An ink jet printer according to any one of claims 1 to 8,
An ink jet printer system comprising: a personal computer connected to the ink jet printer so as to be able to transmit and receive signals.

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