JP7234791B2 - Print head and liquid ejection device - Google Patents

Description

The present invention relates to printheads and liquid ejection devices.

A liquid ejection device such as an inkjet printer ejects liquid such as ink filled in a cavity from a nozzle by driving a piezoelectric element provided in a print head with a drive signal to print characters or an image on a recording medium. Form. In such a liquid ejecting apparatus, if there is a problem with the print head, there is a risk of an ejection failure in which the liquid cannot be ejected normally from the nozzles. When such an ejection abnormality occurs, the ejection accuracy of ink ejected from the nozzles may deteriorate, and the quality of the image formed on the recording medium may deteriorate.

Japanese Patent Application Laid-Open No. 2002-200001 discloses a self-diagnostic function in which the head unit (printhead) itself determines whether or not it is possible to form dots that satisfy normal print quality according to a plurality of signals input to the printhead. A liquid ejecting apparatus is disclosed in which a signal for executing the self-diagnostic function and a signal for executing a printing process of ejecting ink from nozzles propagate through a common signal path.

JP 2017-114020 A

However, when a signal for executing the self-diagnostic function and a signal for executing the printing process of ejecting ink from the nozzles are propagated through a common signal path, the self-diagnostic circuit for executing the self-diagnostic function As a result, the waveform of the signal for executing the printing process may be distorted, and as a result, the ink ejection accuracy may be deteriorated. That is, when the signal for executing the self-diagnostic function and the signal for executing the printing process are propagated through a common signal path, the self-diagnostic function of the print head can be normally executed and the ink ejection accuracy can be improved. It may be difficult to reduce the risk of deterioration of the print processing and to execute the printing process.

One aspect of the liquid ejection device according to the present invention includes:
a print head that ejects liquid;
a control circuit for controlling the operation of the printhead;
with
The print head is
a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
has
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
The sixth wiring electrically connects the first integrated circuit and the first wiring board.

In one aspect of the liquid ejection device,
the printhead having a second integrated circuit;
The second integrated circuit is provided on the first wiring board,
The first wiring board has a seventh wiring and an eighth wiring,
the seventh wiring electrically connects the fifth wiring and the second integrated circuit;
The eighth wiring may electrically connect the sixth wiring and the second integrated circuit.

In one aspect of the liquid ejection device,
The connector and the first integrated circuit may be provided on the same surface of the circuit board.

In one aspect of the liquid ejection device,
The first wiring board may be a flexible wiring board.

In one aspect of the liquid ejection device,
The print head has a second wiring board electrically connected to the circuit board,
A shortest distance between the first wiring board and the connector may be shorter than a shortest distance between the second wiring board and the connector.

In one aspect of the liquid ejection device,
The print head has a plurality of wiring boards including the first wiring board and the second wiring board,
The first wiring board may be provided closest to the connector among the plurality of wiring boards.

In one aspect of the liquid ejection device,
A frequency of a signal propagating through the first wiring may be higher than a frequency of a signal propagating through the second wiring.

In one aspect of the liquid ejection device,
A frequency of a signal propagating through the first wiring may be higher than a frequency of a signal propagating through the third wiring.

In one aspect of the liquid ejection device,
The first integrated circuit may determine whether normal ejection of liquid is possible based on the first signal, the second signal, the third signal, and the fourth signal.

In one aspect of the liquid ejection device,
A drive signal output circuit that outputs a drive signal is provided,
The drive signal may include a first waveform for ejecting liquid from the printhead, a second waveform, and a constant voltage waveform provided between the first waveform and the second waveform.

In one aspect of the liquid ejection device,
The first terminal may also serve as a terminal to which the first signal and a fifth signal that defines waveform selection of the drive signal are input.

In one aspect of the liquid ejection device,
The second terminal may also serve as a terminal to which the second signal and a sixth signal that defines the ejection timing of the liquid are input.

In one aspect of the liquid ejection device,
The sixth signal may be input to the second terminal while the drive signal has the constant voltage waveform.

In one aspect of the liquid ejection device,
The third terminal may also serve as a terminal to which the third signal and a seventh signal that defines waveform switching timing of the driving signal are input.

In one aspect of the liquid ejection device,
The seventh signal may be input to the third terminal while the drive signal has the constant voltage waveform.

In one aspect of the liquid ejection device,
The fourth terminal may also serve as a terminal to which the fourth signal and an eighth signal that defines the operation timing of the print head are input.

One aspect of the print head according to the present invention includes:
a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
with
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
The sixth wiring electrically connects the first integrated circuit and the first wiring board.

1 is a diagram showing a schematic configuration of a liquid ejection device; FIG. 3 is a block diagram showing the electrical configuration of the liquid ejection device; FIG. FIG. 4 is a diagram showing an example of a waveform of a drive signal COM; FIG. 4 is a diagram showing an example of a waveform of a drive signal VOUT; 4 is a diagram showing the configuration of a drive signal selection circuit; FIG. FIG. 10 is a diagram showing the decoded contents of a decoder; 4 is a diagram showing the configuration of a selection circuit corresponding to one ejection section; FIG. FIG. 4 is a diagram for explaining the operation of the drive signal selection circuit; 4 is a diagram showing the configuration of a temperature abnormality detection circuit; FIG. 1 is a perspective view showing the configuration of a print head; FIG. 4 is a plan view showing the structure of an ink ejection surface; FIG. 4 is a diagram showing a schematic configuration of one of a plurality of ejection units included in the head; FIG. It is a top view at the time of seeing a board|substrate from a 2nd surface. FIG. 4 is a plan view of the substrate when viewed from the first surface; 3 is a diagram showing the configuration of connectors 350 and 360. FIG. FIG. 10 is a diagram showing another configuration of connectors 350 and 360; 3 is a cross-sectional view of the print head viewed from the Y direction; FIG. FIG. 18 is an enlarged view of the X portion indicated by the dashed line in FIG. 17; 4 is a diagram for explaining details of signals input to a connector 350; FIG. FIG. 10 is a diagram for explaining details of signals input to a connector 360; FIG. It is a figure which shows an example of the wiring formed in the 1st surface of a board|substrate. It is a figure which shows the structure of a flexible wiring board. FIG. 7 is a block diagram showing the electrical configuration of a liquid ejection device according to a second embodiment; FIG. 11 is a perspective view showing the configuration of a print head in a second embodiment; FIG. 9 is a plan view showing the configuration of an ink ejection surface in a second embodiment; It is a top view at the time of seeing the board|substrate in 2nd Embodiment from a 2nd surface. It is a top view at the time of seeing the board|substrate in 2nd Embodiment from a 1st surface. 4 is a diagram showing the configuration of connectors 370 and 380. FIG. FIG. 10 is a cross-sectional view of the print head in the second embodiment when viewed from the Y direction; FIG. 10 is a diagram for explaining details of signals input to a connector 350 in the second embodiment; FIG. FIG. 11 is a diagram for explaining details of signals input to a connector 360 in the second embodiment; FIG. 4 is a diagram for explaining details of signals input to a connector 370; FIG. 4 is a diagram for explaining details of signals input to a connector 380; FIG. It is a figure which shows an example of the wiring formed in the 1st surface of the board|substrate in 2nd Embodiment. It is a figure for demonstrating the structure of the piezoelectric element in a modification, and the discharge operation|movement of a liquid.

Preferred embodiments of the present invention will be described below with reference to the drawings. The drawings used are for convenience of explanation. It should be noted that the embodiments described below do not unduly limit the scope of the invention described in the claims. Moreover, not all the configurations described below are essential constituent elements of the present invention.

1 First Embodiment 1.1 Overview of Liquid Ejecting Apparatus FIG. 1 is a diagram showing a schematic configuration of a liquid ejecting apparatus 1 . The liquid ejecting apparatus 1 reciprocates a carriage 20 on which a print head 21 that ejects ink, which is an example of a liquid, is mounted, and ejects ink onto the conveyed medium P to eject an image onto the medium P. It is a serial printing type inkjet printer that forms In the following description, the direction in which the carriage 20 moves is the X direction, the direction in which the medium P is conveyed is the Y direction, and the direction in which ink is ejected is the Z direction. Although the X direction, the Y direction, and the Z direction are described as directions orthogonal to each other, the various components constituting the liquid ejecting apparatus 1 are not limited to being orthogonal to each other. Moreover, as the medium P, any printing target such as printing paper, resin film, and fabric can be used.

The liquid ejection device 1 includes a liquid container 2 , a control mechanism 10 , a carriage 20 , a moving mechanism 30 and a transport mechanism 40 .

A plurality of types of ink to be ejected onto the medium P are stored in the liquid container 2 . Liquid container 2
The colors of the ink stored in are black, cyan, magenta, yellow, red, gray, and the like. As the liquid container 2 in which such ink is stored, an ink cartridge, a bag-shaped ink pack formed of a flexible film, an ink tank capable of replenishing ink, or the like is used.

The control mechanism 10 includes a processing circuit such as a CPU (Central Processing Unit) or FPGA (Field Programmable Gate Array) and a memory circuit such as a semiconductor memory, and controls each element of the liquid ejection device 1 .

A print head 21 is mounted on the carriage 20 . Also, the carriage 20 is fixed to an endless belt 32 included in the moving mechanism 30 . Note that the liquid container 2 may also be mounted on the carriage 20 .

A control signal Ctrl-H for controlling the print head 21 and one or a plurality of drive signals COM for driving the print head 21 output by the control mechanism 10 are input to the print head 21 . Then, the print head 21 ejects the ink supplied from the liquid container 2 based on the control signal Ctrl-H and the drive signal COM.

A moving mechanism 30 includes a carriage motor 31 and an endless belt 32 . The carriage motor 31 operates based on the control signal Ctrl-C input from the control mechanism 10 . The endless belt 32 rotates according to the operation of the carriage motor 31 . As a result, the carriage 20 fixed to the endless belt 32 reciprocates in the X direction.

The transport mechanism 40 includes a transport motor 41 and transport rollers 42 . The transport motor 41 operates based on the control signal Ctrl-T input from the control mechanism 10 . The transport roller 42 rotates according to the operation of the transport motor 41 . As the transport roller 42 rotates, the medium P is transported in the Y direction.

As described above, the liquid ejecting apparatus 1 ejects ink from the print head 21 mounted on the carriage 20 in conjunction with the transport of the medium P by the transport mechanism 40 and the reciprocating motion of the carriage 20 by the moving mechanism 30 . , ink is landed at an arbitrary position on the surface of the medium P to form a desired image on the medium P. FIG.

1.2 Electrical Configuration of Liquid Ejecting Apparatus FIG. 2 is a block diagram showing the electrical configuration of the liquid ejecting apparatus 1. As shown in FIG. The liquid ejection device 1 includes a control mechanism 10 , a print head 21 , a carriage motor 31 , a transport motor 41 and a linear encoder 90 .

The control mechanism 10 includes a drive signal output circuit 50 , a control circuit 100 and a power supply circuit 110 . The control circuit 100 includes, for example, a processor such as a microcontroller. The control circuit 100 generates and outputs data and various signals for controlling the liquid ejecting apparatus 1 based on various signals such as image data input from the host computer.

Specifically, the control circuit 100 grasps the scanning position of the print head 21 based on the detection signal input from the linear encoder 90 . The control circuit 100 then generates and outputs various signals corresponding to the scanning position of the print head 21 . Specifically, the control circuit 100 generates a control signal Ctrl-C for controlling the reciprocation of the print head 21 and outputs it to the carriage motor 31 . The control circuit 100 also generates a control signal Ctrl-T for controlling the transport of the medium P and outputs it to the transport motor 41 . The control signal Ctrl-C may be input to the carriage motor 31 after signal conversion via a carriage motor driver (not shown). may be input to the conveying motor 41 after being signal-converted via the .

Further, the control circuit 100 outputs setting signals TD1 to TDn, change signal CH, latch signal LAT, and clock signal SCK are generated and output to the print head 21 .

The control circuit 100 also generates diagnostic signals DIG-A to DIG-D for diagnosing whether or not the print head 21 is capable of normal ejection of liquid, and outputs them to the print head 21 . Here, in the liquid ejecting apparatus 1 according to the first embodiment, each of the diagnosis signals DIG-A to DIG-D and each of the latch signal LAT, clock signal SCK, change signal CH, and setting signal TD1 are common. Input to print head 21 via a propagation path. Specifically, the diagnostic signal DIG-A and the latch signal LAT are input via a common propagation path, the diagnostic signal DIG-B and the clock signal SCK are input via a common propagation path, and the diagnostic signal DIG -C and the change signal CH are input via a common propagation path, and the diagnostic signal DIG-D and the setting signal TD1 are input via a common propagation path.

The control circuit 100 also outputs a drive control signal dA, which is a digital signal, to the drive signal output circuit 50 .

The drive signal output circuit 50 includes a drive circuit 50a. The drive control signal dA is input to the drive circuit 50a. The drive circuit 50a digital-to-analog converts the drive control signal dA, and class D-amplifies the converted analog signal to generate the drive signal COM. That is, the drive control signal dA is a digital signal that defines the waveform of the drive signal COM, and the drive signal output circuit 50 class D-amplifies the waveform defined by the drive control signal dA to generate the drive signal COM. Output. Therefore, the drive control signal dA may be any signal that can define the waveform of the drive signal COM. For example, the drive control signal dA may be an analog signal. The drive circuit 50a included in the drive signal output circuit 50 only needs to be able to amplify the waveform defined by the drive control signal dA. good too.

The drive signal output circuit 50 also outputs a reference voltage signal CGND indicating the reference potential of the drive signal COM. The reference voltage signal CGND may be, for example, a ground potential signal with a voltage value of 0V, or may be a DC voltage signal with a voltage value of 6V or the like.

The drive signal COM and the reference voltage signal CGND are branched in the control mechanism 10 and then output to the print head 21 . Specifically, the drive signal COM is branched into n drive signals COM1 to COMn corresponding to n drive signal selection circuits 200 described later in the control mechanism 10, and then output to the print head 21. . Similarly, the reference voltage signal CGND is branched into n reference voltage signals CGND 1 to CGNDn in the control mechanism 10 and then output to the print head 21 . This drive signal COM is an example of the drive signal, and each of the drive signals COM1 to COMn obtained by branching the drive signal COM is also an example of the drive signal.

The power supply circuit 110 generates and outputs voltages VHV, VDD1, VDD2 and a ground signal GND. The voltage VHV is a DC voltage signal with a voltage value of, for example, 42V. Also, the voltages VDD1 and VDD2 are signals of DC voltage with a voltage value of, for example, 3.3V. Further, the ground signal GND is a signal indicating the reference potential of the voltages VHV, VDD1, and VDD2, and is a ground potential signal with a voltage value of 0 V, for example. The voltage VHV is used as a voltage for amplification in the drive signal output circuit 50, and the voltages VDD1 and VDD2 are used as power supply voltages and control voltages for various configurations in the control mechanism 10, respectively. The voltages VHV, VDD1, VDD2 and the ground signal GND are also output to the print head 21 . The voltage values of the voltages VHV, VDD1, VDD2 and the ground signal GND are not limited to 42V, 3.3V and 0V described above. Also, the power supply circuit 110 may generate and output signals of a plurality of voltage values other than the voltages VHV, VDD1, VDD2, and the ground signal GND.

As described above, the control circuit 100 generates various signals for controlling the operation of the print head 21 and outputs them to the print head 21 . That is, control circuit 100 controls the operation of print head 21 .

The print head 21 includes drive signal selection circuits 200-1 to 200-n, a temperature detection circuit 210, a diagnostic circuit 240, temperature abnormality detection circuits 250-1 to 250-n, and a plurality of ejection portions 600. include.

The diagnostic circuit 240 includes sets of diagnostic signal DIG-A and latch signal LAT, diagnostic signal DIG-B and clock signal SCK, diagnostic signal DIG-C and change signal CH, and diagnostic signal DIG-D and setting signal TD1. They are propagated and input through common wiring. Then, the diagnostic circuit 240 diagnoses whether or not ink can be discharged normally based on the diagnostic signals DIG-A to DIG-D. In other words, the diagnostic circuit 240 determines whether ink can be ejected normally based on the diagnostic signals DIG-A to DIG-D.

For example, the diagnostic circuit 240 detects whether the voltage values of any one of the input diagnostic signals DIG-A to DIG-D or all of the signals are normal, and based on the detection result, may be used to diagnose whether the print head 21 and the control mechanism 10 are properly connected. In addition, the diagnostic circuit 240 selects one of the input diagnostic signals DIG-A to DIG-D or a combination of the logic levels of all the signals to select a drive signal selection circuit included in the print head 21. 200-1 to 200-n and the piezoelectric element 60 are operated to detect whether or not the voltage value resulting from the operation is normal, and based on the detection result, the print head 21 is normal. You may diagnose whether it is operable or not. That is, the print head 21 performs self-diagnosis based on the diagnostic result of the diagnostic circuit 240 to determine whether ink can be ejected normally. Here, the diagnostic signal DIG-A is an example of the second signal, the diagnostic signal DIG-B is an example of the fourth signal, the diagnostic signal DIG-C is an example of the third signal, and the diagnostic signal DIG-D is an example of the third signal. is an example of the first signal.

When the diagnostic circuit 240 determines that the print head 21 can eject ink normally, the diagnostic circuit 240 converts the latch signal LAT, the clock signal SCK, and the change signal CH into the latch signal cLAT, the clock signal cSCK, and the change signal CH. and a change signal cCH. Here, the diagnostic signal DIG-D and the setting signal TD1 are branched at the print head 21, one of which is input to the diagnostic circuit 240, and the other is input to the drive signal selection circuit 200-1. be done. In other words, the setting signal TD1 is input to the drive signal selection circuit 200-1 without going through the diagnostic circuit 240. FIG.

The change signal cCH, latch signal cLAT, and clock signal cSCK output by the diagnostic circuit 240 may have the same waveforms as the change signal CH, latch signal LAT, and clock signal SCK input to the diagnostic circuit 240. good. That is, when the diagnostic circuit 240 determines that the print head 21 can eject ink normally, terminals of the diagnostic circuit 240 to which the latch signal LAT, the clock signal SCK, and the change signal CH are input, Latch signal cLAT, clock signal cSCK, and change signal c
The terminals of the diagnostic circuit 240 to which each CH is output may be electrically connected inside the diagnostic circuit 240 . Further, the change signal cCH, the latch signal cLAT, and the clock signal cSCK may be signals obtained by correcting the respective waveforms of the change signal CH, the latch signal LAT, and the clock signal SCK in the diagnostic circuit 240 .

Further, the diagnostic circuit 240 generates a diagnostic signal DIG-E indicating diagnostic results based on the diagnostic signals DIG-A to DIG-D, and outputs the diagnostic signal DIG-E to the control circuit 100 . Here, the diagnostic circuit 240 includes one or more integrated circuit (IC) devices.

Voltages VHV and VDD1, drive signals COM1 to COMn, setting signals TD1 to TDn, clock signal cSCK, latch signal cLAT, and change signal cCH are input to the drive signal selection circuits 200-1 to 200-n, respectively. The voltages VHV and VDD1 function as power supply voltages and control voltages for the drive signal selection circuits 200-1 to 200-n, respectively. Each of the drive signal selection circuits 200-1 to 200-n selects the drive signals COM1 to COMn based on the input setting signals TD1 to TDn, clock signal cSCK, latch signal cLAT, and change signal cCH. Or by deselecting it, the drive signals VOUT1 to VOUTn are generated.

The drive signals VOUT1 to VOUTn generated by the drive signal selection circuits 200-1 to 200-n are supplied to the piezoelectric elements 60 included in the corresponding ejection portions 600, respectively. The piezoelectric element 60 is displaced by being supplied with drive signals VOUT1 to VOUTn. Then, an amount of ink corresponding to the displacement caused by the piezoelectric element 60 is ejected from the ejection section 600 .

Specifically, the drive signal COM1, the setting signal TD1, the latch signal cLAT, the change signal cCH, and the clock signal cSCK are input to the drive signal selection circuit 200-1. The drive signal selection circuit 200-1 selects or deselects the waveform of the drive signal COM1 based on the setting signal TD1, the latch signal cLAT, the change signal cCH, and the clock signal cSCK, thereby generating the drive signal VOUT1. Output. The drive signal VOUT1 is supplied to one end of the piezoelectric element 60 of the discharge section 600 provided correspondingly. A reference voltage signal CGND1 is supplied to the other end of the piezoelectric element 60 . The piezoelectric element 60 is displaced by the potential difference between the drive signal VOUT1 and the reference voltage signal CGND1.

Similarly, the drive signal COMi, the setting signal TDi, the latch signal cLAT, the change signal cCH, and the clock signal cSCK are input to the drive signal selection circuit 200-i (where i is one of 1 to n). The drive signal selection circuit 200-i generates the drive signal VOUTi by selecting or deselecting the waveform of the drive signal COMi based on the setting signal TDi, latch signal cLAT, change signal cCH, and clock signal cSCK. Output. The drive signal VOUTi is supplied to one end of the piezoelectric element 60 of the discharge section 600 provided correspondingly. A reference voltage signal CGNDi is supplied to the other end of the piezoelectric element 60 . The piezoelectric element 60 is displaced by the potential difference between the drive signal VOUTi and the reference voltage signal CGNDi.

The print head 21 has a plurality of piezoelectric elements 60 corresponding to each of the n drive signal selection circuits 200-1 to 200-n. In other words, the print head 21 is formed by a drive element group formed by a plurality of piezoelectric elements 60 corresponding to the drive signal selection circuit 200-1 and a plurality of piezoelectric elements 60 corresponding to the drive signal selection circuit 200-2. and a plurality of drive element groups including the drive element groups that are connected to each other. Further, each of drive signal selection circuits 200-1 to 200-n has the same circuit configuration. Therefore, in the following description, when there is no need to distinguish between the drive signal selection circuits 200-1 to 200-n, they are referred to as the drive signal selection circuit 200. In this case, the drive signals COM1 to COM input to the drive signal selection circuit 200 are used. drive signal CO
M, the setting signals TD1 to TDn are referred to as setting signals TD, and the drive signals VOUT1 to VOUTn output from the drive signal selection circuit 200 are referred to as drive signals VOUT. Details of the operation of the drive signal selection circuit 200 will be described later. Here, each of the drive signal selection circuits 200-1 to 200-i is configured as an integrated circuit device, for example. Among the setting signals TD1 to TTDn input corresponding to the drive signal selection circuits 200-1 to 200-n, they are input to the drive signal selection circuit 200-1 and define the waveform selection of the drive signal COM1. The setting signal TD1 is an example of the fifth signal.

Temperature abnormality detection circuits 250-1 to 250-n are provided corresponding to drive signal selection circuits 200-1 to 200-n, respectively. Then, the temperature abnormality detection circuits 250-1 to 250-n diagnose the presence or absence of temperature abnormality in the corresponding drive signal selection circuits 200-1 to 200-n. Specifically, temperature abnormality detection circuits 250-1 to 250-n operate using voltage VDD2 as a power supply voltage. Temperature abnormality detection circuits 250-1 to 250-n detect the temperature of corresponding drive signal selection circuits 200-1 to 200-n, and if the temperature is determined to be normal, the temperature is set to high level ( H level) abnormal signal cXHOT is generated and output to the diagnostic circuit 240 . On the other hand, when each of the temperature abnormality detection circuits 250-1 to 250-n determines that the temperature of the corresponding drive signal selection circuits 200-1 to 200-n is abnormal, a low level (L level) abnormality signal is generated. cXHOT is generated and output to diagnostic circuitry 240 .

The diagnostic circuit 240 determines whether or not the temperatures of the drive signal selection circuits 200-1 to 200-n are abnormal based on the logic level of the input abnormality signal cXHOT, and outputs the abnormality signal XHOT based on the determination result. Output. That is, the judgment that the temperature of the drive signal selection circuits 200-1 to 200-n is abnormal in each of the temperature abnormality detection circuits 250-1 to 250-n is also an example of the self-diagnosis of the print head 21. . The diagnosis circuit 240 may output an abnormality signal XHOT of a specific logic level based on whether the temperatures of the drive signal selection circuits 200-1 to 200-n are abnormal. The abnormal signal cXHOT may be output as it is as the abnormal signal XHOT. In other words, the abnormality signal cXHOT may be output to the control circuit 100 via the diagnostic circuit 240 as the abnormality signal XHOT. As described above, the diagnostic signal DIG-E and the abnormal signal XHOT generated by the diagnostic circuit 240 propagate to the control circuit 100 via a common propagation path.

Here, each of temperature abnormality detection circuits 250-1 to 250-n has the same circuit configuration. Therefore, in the following description, the temperature abnormality detection circuits 250-1 to 250-n are referred to as the temperature abnormality detection circuit 250 when there is no need to distinguish them. Details of the temperature abnormality detection circuit 250 will be described later. Further, each of the temperature abnormality detection circuits 250-1 to 250-i is configured as, for example, an integrated circuit device, and the temperature abnormality detection circuit 250-i and the corresponding drive signal selection circuit 200-i are 1. may be configured as one integrated circuit device.

Temperature detection circuit 210 includes a temperature detection element such as a thermistor. Based on the detection signal detected by the temperature detection element, an analog temperature signal TH including temperature information of the print head 21 is generated and output to the control circuit 100 .

1.3 Example of Drive Signal Waveform Here, an example of the waveform of the drive signal COM generated by the drive signal output circuit 50 and an example of the waveform of the drive signal VOUT supplied to the piezoelectric element 60 are shown in FIGS. will be used to explain.

FIG. 3 is a diagram showing an example of the waveform of the drive signal COM. As shown in FIG. 3, the drive signal COM consists of a trapezoidal waveform Adp1 arranged in a period T1 from the rise of the latch signal LAT to the rise of the change signal CH, and and a trapezoidal waveform Adp3 arranged in a period T3 after the period T2 until the next rise of the latch signal LAT. Then, when the trapezoidal waveform Adp1 is supplied to one end of the piezoelectric element 60, the ejection section 600 corresponding to the piezoelectric element 60 ejects a moderate amount of ink. Also, when the trapezoidal waveform Adp2 is supplied to one end of the piezoelectric element 60, the ejection section 600 corresponding to the piezoelectric element 60 ejects a small amount of ink that is less than the medium amount. Also, when the trapezoidal waveform Adp3 is supplied to one end of the piezoelectric element 60, ink is not ejected from the ejection section 600 corresponding to the piezoelectric element 60. FIG. This trapezoidal waveform Adp3 is a waveform for preventing an increase in ink viscosity by vibrating the ink in the vicinity of the nozzle openings of the ejection section 600 .

Here, the cycle Ta from when the latch signal LAT shown in FIG. As described above, the latch signal LAT and the latch signal cLAT are signals that define the ejection timing of the ink from the print head 21, and the change signal CH and the change signal cCH are the trapezoidal waveforms Adp1 and Adp2 included in the drive signal COM. , Adp3 is a signal that defines the waveform switching timing of Adp3. This latch signal LAT is an example of a sixth signal, and the change signal CH is an example of a seventh signal.

Here, the setting signal TD includes data corresponding to the number of ejection sections 600 that the print head 21 has in the period Ta. In other words, the setting signal TD includes logic level data corresponding to the number of the ejection sections 600 in the period Ta. In other words, the frequency of the setting signal TD is higher than the frequencies of the change signal CH and the change signal cCH.

Also, the voltages at the start timings and the end timings of the trapezoidal waveforms Adp1, Adp2, and Adp3 are all common to the voltage Vc. That is, each of the trapezoidal waveforms Adp1, Adp2, and Adp3 is a waveform that starts at voltage Vc and ends at voltage Vc. The drive signal COM may be a waveform signal in which one or two trapezoidal waveforms are continuous, or may be a waveform signal in which four or more trapezoidal waveforms are continuous in the period Ta.

As described above, the drive signal COM is provided between the trapezoidal waveforms Adp1, Adp2, and Adp3 for ejecting ink from the print head 21, between the trapezoidal waveforms Adp1 and Adp2, and between the trapezoidal waveforms Adp2 and Adp3. and the waveform of the voltage Vc applied to it. Here, any one of the trapezoidal waveforms Adp1, Adp2, Adp3 is an example of the first waveform, any one of the different trapezoidal waveforms Adp1, Adp2, Adp3 is an example of the second waveform, and the waveform of the voltage Vc is It is an example of a constant voltage waveform.

Also, the trapezoidal waveforms Adp1, Adp2, and Adp3 included in the drive signal COM are generated during the period defined by the change signal CH within the cycle Ta defined by the latch signal LAT. That is, the trapezoidal waveforms Adp1, Adp2, and Adp3 are output between the latch signal LAT and the change signal CH, between the change signal CH and the change signal CH, or between the change signal CH and the latch signal LAT. . In other words, the latch signal LAT and the change signal CH are input to the print head 21 while the drive signal COM is at the voltage Vc. This reduces the possibility that the high-voltage drive signal COM interferes with the change signal CH and the latch signal LAT. It is possible to reduce the impact on the accuracy of the ink that is used.

FIG. 4 is a diagram showing an example of waveforms of the driving signal VOUT corresponding to "large dot", "medium dot", "small dot" and "non-recording".

As shown in FIG. 4, the driving signal VOUT corresponding to the "large dot" has a trapezoidal waveform Adp1 arranged in the period T1, a trapezoidal waveform Adp2 arranged in the period T2, and a trapezoidal waveform Adp2 arranged in the period T3 in the period Ta. The waveform is a series of constant waveforms at the voltage Vc. When this drive signal VOUT is supplied to one end of the piezoelectric element 60, a medium amount of ink and a small amount of ink are ejected from the ejection section 600 corresponding to the piezoelectric element 60 in the cycle Ta. . Therefore, a large dot is formed on the medium P by each ink landing and coalescing.

The driving signal VOUT corresponding to the "medium dot" has a waveform in which the trapezoidal waveform Adp1 arranged in the period T1 and the constant waveform of the voltage Vc arranged in the periods T2 and T3 are continuous in the period Ta. there is When this drive signal VOUT is supplied to one end of the piezoelectric element 60, a moderate amount of ink is ejected from the ejection section 600 corresponding to the piezoelectric element 60 in the period Ta. Therefore, this ink lands on the medium P to form a medium dot.

The drive signal VOUT corresponding to the "small dot" has a waveform in which the constant waveform of the voltage Vc arranged in the periods T1 and T3 and the trapezoidal waveform Adp2 arranged in the period T2 are continuous in the period Ta. there is When the drive signal VOUT is supplied to one end of the piezoelectric element 60, a small amount of ink is ejected from the ejection section 600 corresponding to the piezoelectric element 60 in the period Ta. Therefore, the ink lands on the medium P to form small dots.

The driving signal VOUT corresponding to "non-recording" has a waveform in which the constant waveform of the voltage Vc arranged in the periods T1 and T2 and the trapezoidal waveform Adp3 arranged in the period T3 are continuous in the period Ta. there is When the drive signal VOUT is supplied to one end of the piezoelectric element 60, the ink near the nozzle opening of the ejection section 600 corresponding to the piezoelectric element 60 vibrates only slightly during the period Ta, and the ink is not ejected. Therefore, no ink lands on the medium P and no dot is formed.

Here, the constant waveform of the voltage Vc means that when none of the trapezoidal waveforms Adp1, Adp2, and Adp3 is selected as the drive signal VOUT, the immediately preceding voltage Vc changes from the voltage held by the capacitance component of the piezoelectric element 60. It is also a waveform. Therefore, when none of the trapezoidal waveforms Adp1, Adp2, Adp3 is selected as the drive signal VOUT, the voltage Vc is supplied to the piezoelectric element 60 as the drive signal VOUT.

The drive signal COM and the drive signal VOUT shown in FIGS. 3 and 4 are merely examples, and the movement speed of the carriage 20 on which the print head 21 is mounted, the physical properties of the ink supplied to the print head 21, and the medium Various combinations of waveforms may be used depending on the material of P and the like.

1.4 Configuration of Drive Signal Selection Circuit Next, the configuration and operation of the drive signal selection circuit 200 will be described with reference to FIGS. 5 to 8. FIG. FIG. 5 is a diagram showing the configuration of the drive signal selection circuit 200. As shown in FIG. As shown in FIG. 5, the drive signal selection circuit 200 has a control logic circuit 260 and a plurality of selection control circuits 270 . Here, the plurality of selection control circuits 270 are provided corresponding to each of the plurality of ejection portions 600 . In other words, the drive signal selection circuit 200 has the same number of selection control circuits 270 as the total number m of the ejection sections 600 . In the following description, from the upstream side where the setting signal TD is input to the driving signal selection circuit 200, the stages will be referred to as 1st stage, 2nd stage, . , m stages are sometimes referred to as selection control circuits 270-1, 270-2, . . . , 270-m.

A setting signal TD, a latch signal cLAT, a change signal cCH, a clock signal cSCK, and a drive signal COM are input to the drive signal selection circuit 200 . Then, the drive signal selection circuit 200 selects or deselects the trapezoidal waveforms Adp1, Adp2, Adp3 included in the drive signal COM based on the setting signal TD, the latch signal cLAT, the change signal cCH, and the clock signal cSCK. Output as VOUT.

The control logic circuit 260 has an SP shift register (S/R) group 261 and a selection control signal generation group 262 . The SP shift register group 261 holds the setting data signal SP included in the setting signal TD input in synchronization with the clock signal cSCK. The selection control signal generation group 262 latches the setting data signal SP held in the SP shift register group 261, and generates and outputs selection control signals q0 to q3 based on the latched setting data signal SP.

The selection control circuit 270 has a first shift register 222 a, a second shift register 222 b, a first latch circuit 224 a, a second latch circuit 224 b, a decoder 226 and a selection circuit 230 .

The first shift register 222a and the second shift register 222b hold the print data signal SI included in the setting signal TD input in synchronization with the clock signal cSCK. Specifically, the setting signal TD includes upper print data SIH and lower print data SIL corresponding to each of the ejection units 600 as the print data signal SI. Among the print data signals SI transmitted in synchronization with the clock signal cSCK, the upper print data SIH are held in the first shift register 222a, and the lower print data SIL are held in the second shift register 222b. The upper print data SIH held in the first shift register 222a and the lower print data SIL held in the second shift register 222b define the amount of ink ejected from the corresponding ejector 600. FIG. Here, in the following description, the upper print data SIH and the lower print data SIL corresponding to the ejection section 600 may be referred to as print data [SIH, SIL]. are sometimes referred to as print data [SIH1, SIL1], print data [SIH2, SIL2], . . . , print data [SIHm, SILm].

Here, the SP shift register group 261, the first shift register 222a, and the second shift register 222b described above are connected in cascade in the drive signal selection circuit 200. FIG. Specifically, the SP shift register group 261, the first shift register 222a, and the second shift register 222b correspond to the SP shift register group 261, stages 1 to m, respectively, in the drive signal selection circuit 200. The second shift registers 222b and the first shift registers 222a corresponding to stages 1 to m are connected in cascade in this order. That is, in synchronization with the clock signal cSCK, the setting signal TD is applied to the SP shift register group 261, the second shift register 222b corresponding to each of stages 1 to m, and the first shift register 222b corresponding to each of stages 1 to m. Transferred in the order of the shift register 222a.

That is, the setting signal TD converts the setting data signal SP, the upper print data SIH, and the lower print data SIL into the upper print data SIH corresponding to the m-stage to 1-stage ejection units 600, and the m-stage to 1-stage print data SIL, respectively. is a serial signal including the lower print data SIL corresponding to the ejection unit 600 and the setting data signal SP in this order. Such setting signal TD is sequentially transferred by the SP shift register group 261, the second shift register 222b, and the first shift register 222a, so that the SP shift register group 261 holds the setting data signal SP. , the second shift register 222b holds lower print data SIL corresponding to each of the 1st to m-th discharge sections 600, and the first shift register 222a corresponds to each of the 1st to m-th discharge sections 600. The upper print data SIH to be used is held.

The upper print data SIH corresponding to each of the 1st to m-stage ejection units 600 held in the first shift register 222a is transferred to the 1st-to-mth ejection units 600 corresponding to each of the 1st to m-stage ejection units 600 at the rising edge of the latch signal cLAT. 1 latch circuit 224a. Further, the low-order print data SIL corresponding to each of the 1st to m-th discharge sections 600 held in the second shift register 222b corresponds to each of the 1st to m-th discharge sections 600 at the rising edge of the latch signal cLAT. is latched by the second latch circuit 224b.

The first latch circuit 224a outputs the latched upper print data SIH as latch data LTa, and the second latch circuit 224b outputs the latched lower print data SIL as latch data LTb. In the following description, the latch data LTa output by the first latch circuit 224a corresponding to each of the 1st, 2nd, . , 1st stage, 2nd stage, . In the following description, the latch data LTa, LTb will be referred to as latch data [LTa, LTb], and the latch data [LTa, LTb] corresponding to each of the 1st, 2nd, . , latch data [LTa1, LTb1], latch data [LTa2, LTb2], . . . , latch data [LTam, LTbm].

The decoder 226 receives selection control signals q0 to q3 and latch data [LTa, LTb] corresponding to the print data [SIH, SIL]. Then, the decoder 226 generates and outputs the selection signal S based on the selection control signals q0 to q3 and the latch data [LTa, LTb]. Here, the selection control signals q0 to q3 are signals for defining the logic level of the selection signal S output in each of the periods T1, T2, T3 shown in FIG. 3, and the latch data [LTa, LTb] are: This signal defines the selection of the selection control signals q0 to q3. That is, the decoder 226 decodes the selection control signals q0 to q3 based on the latch data [LTa, LTb] to output the selection signal S at a predetermined logic level in each of the periods T1, T2, T3. The selection signal S output from the decoder 226 may be converted into a high-amplitude logic signal based on the voltage VHV by a level shifter (not shown).

FIG. 6 is a diagram showing the decoded contents of the decoder 226. As shown in FIG. The selection control signal q0 defines the logic levels of the selection signal S as H, H, and L levels in periods T1, T2, and T3, respectively. Selection control signal q1 defines logic levels of selection signal S as H, L, and L levels in periods T1, T2, and T3, respectively. The selection control signal q2 defines the logic levels of the selection signal S as L, H, and L levels in periods T1, T2, and T3, respectively. The selection control signal q3 defines the logic levels of the selection signal S as L, L, and H levels in periods T1, T2, and T3, respectively.

The decoder 226 outputs selection control signals q0 to q3 based on the latch data [LTa, LTb] corresponding to the print data [SIH, SIL] latched by the first latch circuit 224a and the second latch circuit 224b. select. Specifically, the decoder 226 decodes the selection control signals q0, q1, q2, q3 based on the latch data [LTa, LTb], and outputs corresponding logic levels according to the contents of FIG. 6 for each period T1, T2, T3. A selection signal S of is output. For example, in the example shown in FIG. 6, when the latch data [LTa, LTb] input to the decoder 226 are [1, 0], the decoder 226 outputs They respectively output selection signals S of H, L, and L levels.

A selection signal S output from the decoder 226 is input to the selection circuit 230 . FIG. 7 is a diagram showing the configuration of the selection circuit 230 corresponding to one ejection section 600. As shown in FIG. As shown in FIG. 7, the selection circuit 230 has an inverter 232 and a transfer gate 234, which are NOT circuits. The selection signal S is input to the positive control terminal not marked with a circle in the transfer gate 234 , is logically inverted by the inverter 232 , and is input to the negative control terminal marked with a circle in the transfer gate 234 . be. A drive signal COM is supplied to the input terminal of the transfer gate 234 . Specifically, the transfer gate 234 makes the connection between the input end and the output end conductive when the selection signal S is at H level, and makes the connection between the input end and the output end non-conductive when the selection signal S is at L level. Make it conductive. A drive signal VOUT is output from the output terminal of the transfer gate 234 . In the following description, controlling the connection between the input terminal and the output terminal to be conductive is simply referred to as "turning on", and controlling the connection between the input terminal and the output terminal to be non-conductive is simply referred to as "turning off". It may be referred to as "to make".

As described above, the setting signal TD, the latch signal cLAT, the change signal cCH, the clock signal cSCK, and the drive signal COM are input to the drive signal selection circuit 200 . Then, it generates and outputs a drive signal VOUT. Here, the setting signal TD serially includes the print data signal SI and the setting data signal SP, and defines waveform selection of the drive signal COM. The clock signal SCK and the clock signal cSCK are signals for defining the timing at which the setting signal TD is input, and are signals for defining the operation timing of the print head 21 . This clock signal SCK is an example of the eighth signal.

Here, the operation of the drive signal selection circuit 200 will be described with reference to FIG. FIG. 8 is a diagram for explaining the operation of the drive signal selection circuit 200. As shown in FIG. The print data signal SI included in the setting signal TD is serially input in synchronization with the clock signal cSCK and sequentially transferred by the second shift register 222b and the first shift register 222a. Then, when the input of the clock signal cSCK stops, the first shift register 222a holds the upper print data SIH corresponding to each of the ejection units 600, and the second shift register 222b holds the upper print data SIH corresponding to each of the ejection units 600. The low-order print data SIL that have been created are held. In this case, the set data signal SP is held in the SP shift register group 261 .

Then, when the latch signal cLAT rises, the selection control signal generation group 262 latches the set data signal SP held in the SP shift register group 261 . The selection control signal generation group 262 generates and outputs selection control signals q0 to q3 according to the latched setting data signal SP. Also, when the latch signal cLAT rises, each of the first latch circuits 224a latches the upper print data SIH held in the first shift register 222a all at once, and each of the second latch circuits 224b performs the second shift. The lower print data SIL held in the register 222b are latched all at once.

The decoder 226 outputs a logic level selection signal S defined by the selection control signals q0 to q3 according to the dot size defined by the latch data [LTa, LTb] corresponding to the print data [SIH, SIL]. do.

Specifically, the decoder 226 selects the selection control signal q0 when the print data [SIH, SIL] is [1, 1]. Therefore, the decoder 226 outputs the selection signal S of H, H and L levels during the periods T1, T2 and T3. In this case, the selection circuit 230 selects the trapezoidal waveform Adp1 in the period T1, selects the trapezoidal waveform Adp2 in the period T2, and does not select the trapezoidal waveform Adp3 in the period T3. As a result, the drive signal selection circuit 200 generates and outputs the drive signal VOUT corresponding to the "large dot" shown in FIG.

Also, the decoder 226 selects the selection control signal q1 when the print data [SIH, SIL] is [1, 0]. Therefore, the decoder 226 outputs the selection signal S of H, L and L levels during the periods T1, T2 and T3. In this case, the selection circuit 230 selects the trapezoidal waveform Adp1 in the period T1, does not select the trapezoidal waveform Adp2 in the period T2,
The trapezoidal waveform Adp3 is not selected in period T3. As a result, the drive signal selection circuit 200 generates and outputs the drive signal VOUT corresponding to the "medium dot" shown in FIG.

Also, the decoder 226 selects the selection control signal q2 when the print data [SIH, SIL] is [0, 1]. Therefore, the selection signal S of L, H and L levels is output in the periods T1, T2 and T3. In this case, the selection circuit 230 does not select the trapezoidal waveform Adp1 in the period T1, selects the trapezoidal waveform Adp2 in the period T2, and does not select the trapezoidal waveform Adp3 in the period T3. As a result, the drive signal selection circuit 200 generates and outputs the drive signal VOUT corresponding to the "small dot" shown in FIG.

Also, the decoder 226 selects the selection control signal q3 when the print data [SIH, SIL] is [0, 0]. Therefore, the selection signal S of L, L and H levels is output in the periods T1, T2 and T3. In this case, the selection circuit 230 does not select the trapezoidal waveform Adp1 in the period T1, does not select the trapezoidal waveform Adp2 in the period T2, and selects the trapezoidal waveform Adp3 in the period T3. As a result, the drive signal selection circuit 200 generates and outputs the drive signal VOUT corresponding to "non-recording" shown in FIG.

As described above, the drive signal selection circuit 200 selects the waveform of the drive signal COM based on the setting signal TD, the latch signal cLAT, the change signal cCH, and the clock signal cSCK, and generates and outputs the drive signal VOUT. In other words, the drive signal selection circuit 200 selects the waveform of the drive signal COM and supplies it to the piezoelectric element 60 . Here, the drive signal VOUT is generated by selecting or not selecting the waveform of the drive signal COM. Therefore, the drive signal VOUT is also an example of the drive signal output from the drive signal output circuit 50 in a broad sense.

1.5 Configuration of Abnormal Temperature Detecting Circuit Next, the abnormal temperature detecting circuit 250 will be described with reference to FIG. FIG. 9 is a diagram showing the configuration of the temperature abnormality detection circuit 250. As shown in FIG. As shown in FIG. 9, the temperature abnormality detection circuit 250 includes a comparator 251, a reference voltage generation circuit 252, a transistor 253, a plurality of diodes 254 and resistors 255,256. As described above, temperature abnormality detection circuits 250-1 to 250-n all have the same configuration. Therefore, in FIG. 9, illustration of the detailed configuration of the temperature abnormality detection circuits 250-2 to 250-n is omitted.

A voltage VDD2 is input to the reference voltage generation circuit 252 . Then, the reference voltage generation circuit 252 transforms the voltage VDD2 to generate the voltage Vref and supplies it to the + side input terminal of the comparator 251 . The reference voltage generation circuit 252 is composed of, for example, a voltage regulator circuit.

A plurality of diodes 254 are connected in series with each other. Among the plurality of diodes 254 connected in series, the anode terminal of the diode 254 located on the highest potential side is supplied with the voltage VDD2 through a resistor 255, and the cathode of the diode 254 located on the lowest potential side. A ground signal GND is supplied to the terminal. Specifically, the temperature abnormality detection circuit 250 has diodes 254-1, 254-2, 254-3, and 254-4 as the plurality of diodes 254. FIG. The anode terminal of the diode 254 - 1 is supplied with the voltage VDD 2 through the resistor 255 and connected to the negative input terminal of the comparator 251 . The cathode terminal of diode 254-1 is connected to the anode terminal of diode 254-2. The cathode terminal of diode 254-2 is connected to the anode terminal of diode 254-3. The cathode terminal of diode 254-3 is connected to the anode terminal of diode 254-4. A ground signal GND is supplied to the cathode terminal of the diode 254-4. The negative input terminal of the comparator 251 is supplied with the voltage Vdet, which is the sum of the forward voltages of the plurality of diodes 254, by the resistor 255 and the plurality of diodes 254 configured as described above. Note that the number of diodes 254 is not limited to four.

The comparator 251 operates according to the potential difference between the voltage VDD2 and the ground signal GND. Then, the comparator 251 compares the voltage Vref supplied to the + side input terminal and the voltage Vdet supplied to the - side input terminal, and outputs a signal based on the comparison result from the output terminal.

A voltage VDD2 is supplied to the drain terminal of the transistor 253 via a resistor 256 . Also, the gate terminal of the transistor 253 is connected to the output terminal of the comparator 251, and the ground signal GND is supplied to the source terminal. The voltage supplied to the drain terminal of the transistor 253 connected as described above is output from the temperature abnormality detection circuit 250 as the abnormality signal cXHOT.

The voltage value of the voltage Vref generated by the reference voltage generation circuit 252 is smaller than the voltage Vdet when the temperatures of the plurality of diodes 254 are within a predetermined range. In this case, the comparator 251 outputs an L level signal. Therefore, the transistor 253 is turned off, and as a result, the temperature abnormality detection circuit 250 outputs the H level abnormality signal cXHOT.

The forward voltage of the diode 254 has the characteristic of decreasing as the temperature rises. Therefore, when a temperature abnormality occurs in the print head 21, the temperature of the diode 254 rises and the voltage Vdet drops accordingly. Then, when the voltage Vdet falls below the voltage Vref due to the temperature rise, the output signal of the comparator 251 changes from L level to H level. Therefore, transistor 253 is controlled to be on. As a result, the temperature anomaly detection circuit 250 outputs an L-level anomaly signal cXHOT.

Further, as shown in FIG. 9, the outputs of the n temperature abnormality detection circuits 250-1 to 250-n are commonly connected. When a temperature abnormality occurs in any one of the temperature abnormality detection circuits 250-1 to 250-n, the transistor 253 corresponding to the temperature abnormality detection circuit 250 is turned on. As a result, the ground signal GND is supplied via the transistor 253 to the node to which the abnormal signal cXHOT is output. Therefore, the abnormality signal cXHOT output from the temperature abnormality detection circuits 250-1 to 250-n is controlled to L level. That is, the temperature abnormality detection circuits 250-1 to 250-n are wired OR connected. As a result, even if a plurality of temperature abnormality detection circuits 250 are provided in the print head 21, the presence or absence of temperature abnormality in the print head 21 can be detected without increasing the number of wirings for propagating the abnormality signal cXHOT. Abnormal signal cXHOT can be propagated.

1.6 Configuration of Print Head Next, the configuration of the print head 21 will be described. FIG. 10 is a perspective view showing the configuration of the print head 21. As shown in FIG. As shown in FIG. 10, print head 21 has head 310 and substrate 320 . In addition, an ink ejection surface 311 having a plurality of ejection portions 600 formed thereon is positioned on the lower surface of the head 310 in the Z direction. In the following description, it is assumed that the print head 21 has six drive signal selection circuits 200-1 to 200-6. That is, the print head 21 has six drive signal selection circuits 200-1 to 200-1.
-6, six drive signals COM1 to COM6, and six reference voltage signals CGND1 to CGND6 are input.

FIG. 11 is a plan view showing the structure of the ink ejection surface 311. As shown in FIG. As shown in FIG. 11, on the ink ejection surface 311, six nozzle plates 632 having nozzles 651 included in a plurality of ejection portions 600 are arranged in the X direction. In each of the nozzle plates 632, the nozzles 651 are arranged side by side in the Y direction. That is, the ink ejection surface 311 is formed with six nozzle rows L1 to L6. In FIG. 11, the nozzles 651 are arranged in one row in the Y direction in the nozzle rows L1 to L6 formed in each nozzle plate 632, but the nozzles 651 are arranged in two or more rows in the Y direction. They may be provided side by side.

Nozzle rows L1 to L6 are provided corresponding to drive signal selection circuits 200-1 to 200-6, respectively. Specifically, the drive signal VOUT1 output by the drive signal selection circuit 200-1 based on the setting signal TD1 is supplied to one end of the piezoelectric element 60 included in the plurality of ejection units 600 provided in the nozzle row L1, A reference voltage signal CGND1 is supplied to the other end of the piezoelectric element 60 . Similarly, the drive signals VOUT2 to VOUT6 output by the drive signal selection circuits 200-2 to 200-6 based on the setting signals TD2 to TD6 are output by the plurality of ejection units 600 provided in the nozzle rows L2 to L6, respectively. The reference voltage signals CGND2 to CGND6 are supplied to the other ends of the corresponding piezoelectric elements 60, respectively.

Next, the configuration of the ejection section 600 included in the head 310 will be described with reference to FIG. 12 . FIG. 12 is a diagram showing a schematic configuration of one of the plurality of ejection sections 600 included in the head 310. As shown in FIG. As shown in FIG. 12, the head 310 includes a discharge section 600 and a reservoir 641. As shown in FIG.

A reservoir 641 is provided corresponding to each of the nozzle rows L1 to L6. Ink is introduced into the reservoir 641 from the ink supply port 661 .

The ejection part 600 includes a piezoelectric element 60 , a vibration plate 621 , a cavity 631 and a nozzle 651 . The vibration plate 621 deforms as the piezoelectric element 60 provided on the upper surface in FIG. 12 is displaced. The diaphragm 621 functions as a diaphragm that expands/contracts the internal volume of the cavity 631 . The inside of the cavity 631 is filled with ink. The cavity 631 functions as a pressure chamber whose internal volume changes due to displacement of the piezoelectric element 60 . The nozzle 651 is an opening formed in the nozzle plate 632 and communicating with the cavity 631 . Ink stored inside the cavity 631 is ejected from the nozzle 651 according to the change in the internal volume of the cavity 631 .

The piezoelectric element 60 has a structure in which a piezoelectric body 601 is sandwiched between a pair of electrodes 611 and 612 . In the piezoelectric body 601 having this structure, the central portions of the electrodes 611 and 612 and the vibration plate 621 bend vertically in FIG. Specifically, the electrode 611 is supplied with the drive signal VOUT, and the electrode 612 is supplied with the reference voltage signal CGND. When the voltage of the drive signal VOUT increases, the central portion of the piezoelectric element 60 bends upward, and when the voltage of the drive signal VOUT decreases, the central portion of the piezoelectric element 60 bends downward. That is, when the piezoelectric element 60 bends upward, the internal volume of the cavity 631 expands. Thus, ink is drawn from reservoir 641 . Further, when the piezoelectric element 60 bends downward, the internal volume of the cavity 631 is reduced. Therefore, an amount of ink is ejected from the nozzle 651 according to the degree of reduction of the internal volume of the cavity 631 . As described above, the piezoelectric element 60 receives the drive signal VOU based on the drive signal COM.
Driven by T. Ink is ejected from the nozzle 651 by driving the piezoelectric element 60 .

Returning to FIG. 10, the substrate 320 has a first surface 321 and a second surface 322 facing the first surface 321, and a first side 323 and a second side 323 facing the first side 323 in the X direction. It has a substantially rectangular shape formed by two sides 324, a third side 325, and a fourth side 326 facing the third side 325 in the Y direction. The shape of the substrate 320 is not limited to a rectangle, and may be, for example, a polygon such as a hexagon or an octagon. .

Here, the configuration of the substrate 320 will be described with reference to FIGS. 13 and 14. FIG. 13 is a plan view of the substrate 320 viewed from the second surface 322. FIG. 14 is a plan view of the substrate 320 viewed from the first surface 321. FIG.

As shown in FIG. 13, the second surface 322 of the substrate 320 is provided with electrode groups 330a to 330f. Specifically, each of the electrode groups 330a to 330f has a plurality of electrodes arranged side by side in the Y direction. The electrode groups 330a to 330f are arranged in the order of the electrode groups 330a, 330b, 330c, 330d, 330e, and 330f along the Y direction. A flexible printed circuit (FPC: Flexible Printed Circuits) 335 shown in FIG. 17 is electrically connected to each of the electrode groups 330a to 330f provided as described above.

Further, as shown in FIGS. 13 and 14, the substrate 320 has FPC insertion holes 332a to 332c, which are through holes passing through the first surface 321 and the second surface 322, and ink supply path insertion holes 331a to 331f. and are formed.

The FPC insertion hole 332a is located between the electrode group 330a and the electrode group 330b in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 330a and the electrode group 330b. A flexible wiring board 335 is inserted therethrough. The FPC insertion hole 332b is located between the electrode group 330c and the electrode group 330d in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 330c and the electrode group 330d. The flexible wiring board 335 is inserted. The FPC insertion hole 332c is located between the electrode group 330e and the electrode group 330f in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 330e and the electrode group 330f. The flexible wiring board 335 is inserted.

The ink supply path insertion hole 331a is located on the first side 323 side of the electrode group 330a in the X direction. The ink supply path insertion holes 331b and 331c are positioned between the electrode group 330b and the electrode group 330c in the X direction. They are arranged side by side along the Y direction so as to be on the 326 side. The ink supply path insertion holes 331d and 331e are located between the electrode group 330d and the electrode group 330e in the X direction. They are arranged side by side along the Y direction so as to be on the 326 side. The ink supply path insertion hole 331f is positioned on the second side 324 side of the electrode group 330f in the X direction. Each of the ink supply passage insertion holes 331a to 331f is provided with an ink supply passage (not shown) communicating with an ink supply port 661 for introducing ink into the ejection section 600 corresponding to each of the nozzle rows L1 to L6. part is inserted.

13 and 14, the substrate 320 has fixing portions 346 to 349 for fixing the substrate 320 included in the print head 21 to the carriage 20 shown in FIG. Each of the fixing portions 346 to 349 is a through hole penetrating through the first surface 321 and the second surface 322 of the substrate 320 . The substrate 320 and the head 310 are fixed by fixing members such as screws (not shown) inserted through the fixing portions 346 to 349 . Also, the fixing member may fix the print head 21 and the carriage 20 . Moreover, the fixed portions 346 to 349 are not limited to through holes formed in the substrate 320 . For example, the fixing portions 346 to 349 may be configured to fix the substrate 320 and the head 310 by fitting them together.

The fixing portions 346 and 347 are positioned on the first side 323 side of the ink supply path insertion hole 331a in the X direction, and are arranged Y so that the fixing portion 346 is on the third side 325 side and the fixing portion 347 is on the fourth side 326 side. They are arranged side by side along the direction. The fixing portions 348 and 349 are positioned on the second side 324 side of the ink supply path insertion hole 331f in the X direction, and the fixing portion 348 is positioned on the third side 325 side, and the fixing portion 349 is positioned on the fourth side 326 side. are arranged side by side along the Y direction.

Also, as shown in FIG. 14, the first surface 321 of the substrate 320 is provided with an integrated circuit 241 that constitutes the diagnostic circuit 240 shown in FIG. Specifically, the integrated circuit 241 is provided on the first surface 321 side of the substrate 320, between the fixing portion 347 and the fixing portion 349, and on the fourth side 326 side of the electrode groups 330a to 330f. It is

Further, as shown in FIGS. 13 and 14, the substrate 320 is provided with connectors 350 and 360. FIG. The connector 350 is provided along the first side 323 on the first surface 321 side of the substrate 320 . The connector 360 is provided along the first side 323 on the second surface 322 side of the substrate 320 .

Here, the configuration of connectors 350 and 360 will be described with reference to FIG. FIG. 15 is a diagram showing the configuration of connectors 350 and 360. As shown in FIG. As shown in FIG. 15, the connector 350 has a housing 351 , a cable attachment portion 352 formed in the housing 351 and a plurality of terminals 353 . A plurality of terminals 353 are arranged side by side along the first side 323 . Specifically, 26 terminals 353 are arranged side by side along the first side 323 . 353-1, 353-2, . 26. The cable attachment portion 352 is located on the board 320 side of the plurality of terminals 353 in the Z direction. A cable such as a flexible flat cable is attached to the cable attachment portion 352 as a propagation path.

Connector 360 has a housing 361 , a cable attachment portion 362 formed in housing 361 , and a plurality of terminals 363 . A plurality of terminals 363 are arranged side by side along the first side 323 . Specifically, 26 terminals 363 are arranged side by side along the first side 323 . 363-1, 363-2, . 26. The cable attachment portion 362 is located on the board 320 side of the plurality of terminals 363 in the Z direction. A cable such as a flexible flat cable is attached to the cable attachment portion 362 as a propagation path.

Various signals for controlling the operation of the print head 21 are propagated through the cables attached to the connectors 350 and 360 as transmission paths for various control signals. The print head 21 operates based on various signals input through the connectors 350 and 360. FIG.

Here, in the connector 350 shown in FIG. 15, the cable attachment portion 352 is positioned on the substrate 320 side in the Z direction, and the plurality of terminals 353 are positioned on the ink discharge surface 311 side in the Z direction. Like the connector 350, it is preferable that the plurality of terminals 353 be positioned on the substrate 320 side in the Z direction, and the cable attachment portion 352 be positioned on the ink ejection surface 311 side in the Z direction. FIG. 16 is a diagram showing another configuration of connectors 350 and 360. As shown in FIG.

In the liquid ejection device 1, most of the ink ejected from the nozzles 651 lands on the medium P to form an image. However, part of the ink ejected from the nozzle 651 may become mist before landing on the medium P and float inside the liquid ejecting apparatus 1 . Furthermore, even after the ink ejected from the nozzles 651 has landed on the medium P, the movement of the carriage 20 on which the print head 21 is mounted and the airflow generated as the medium P is transported cause the ink to land on the medium P. Ink may float again inside the liquid ejection device 1 . If ink floating inside the liquid ejection device 1 adheres to a plurality of terminals 353 included in the connector 350, there is a risk of short-circuiting between the terminals. is distorted in the waveform of the print head 21, and the ejection accuracy of the ink ejected from the print head 21 may deteriorate.

As in the connector 350 shown in FIG. 16, a plurality of terminals 353 are positioned on the side of the substrate 320 in the Z direction, so that when a cable is attached to the connector 350, floating ink adheres to the inside of the liquid ejection device 1. A plurality of terminals 353 are not provided on the surface on the ink ejection surface 311 side, which is highly likely. Therefore, it is possible to reduce the risk of short circuits between the plurality of terminals 353 included in the connector 350 due to ink floating inside the liquid ejection device 1 . Therefore, it is possible to reduce the possibility that the signal input to the print head 21 is distorted.

In the print head 21 configured as described above, the drive signals COM1 to COM6, the reference voltage signals CGND1 to CGND6, the setting signals TD1 to TD6, the latch signal LAT, the change signal CH, and the clock signal SCK output from the control mechanism 10 are used. A plurality of signals are input to printhead 21 via connectors 350 and 360, including: Of the plurality of signals input to the print head 21, the plurality of signals including the setting signal TD1, the latch signal LAT, the change signal CH, and the clock signal SCK propagate through the wiring pattern provided on the substrate 320 and pass through the diagnostic circuit 240. It is input to an integrated circuit 241 containing. Then, they are output as a latch signal cLAT, a change signal cCH, and a clock signal cSCK. The latch signal cLAT, the change signal cCH, and the clock signal cSCK propagate through wiring patterns provided on the substrate 320 and are input to the electrode groups 330a to 330f, respectively.

Among the plurality of signals input to the print head 21, the plurality of signals including the drive signals COM1 to COM6, the reference voltage signals CGND1 to CGND6, and the setting signals TD1 to TD6 are integrated circuits 241 including the diagnostic circuit 240. It propagates through the wiring pattern provided on the substrate 320 and is input to each of the electrode groups 330a to 330f.

Various signals input to each of the electrode groups 330a to 330f select drive signals corresponding to each of the nozzle rows L1 to L6 via a flexible wiring board 335 electrically connected to each of the electrode groups 330a to 330f. Input to circuits 200-1 to 200-6. FIG. 17 is a cross-sectional view of the print head 21 viewed from the Y direction, and FIG. 18 is an enlarged view of the X portion indicated by broken lines in FIG. Although FIG. 17 shows a plurality of X sections, they all have the same configuration. Therefore, in the description of FIG. 18, only one X portion is illustrated, the FPC insertion holes 332a to 332c are simply referred to as the FPC insertion hole 332, and the ink supply path insertion holes 331a to 331f are simply referred to as the ink supply path insertion hole 331. , and the electrode groups 330 a to 330 f are simply referred to as the electrode group 330 .

As shown in FIGS. 11 and 17, a plurality of nozzle rows L1 to L6 are arranged side by side in the X direction. Specifically, the plurality of nozzle rows L1 to L6 are arranged from the first side 323 side of the substrate 320 where the connector 350 is provided toward the second side 324 side. , and L6. In other words, the nozzle row L1 is positioned closest to the first side 323, and the nozzle row L10 is positioned closest to the second side 324. That is, the shortest distance between the plurality of piezoelectric elements 60 included in the nozzle row L1 corresponding to the drive signal selection circuit 200-1 and the connector 350 is Shorter than the shortest distance between the piezoelectric element 60 and the connector 350 . Furthermore, in this case, between the plurality of piezoelectric elements 60 included in the nozzle row L1 corresponding to the drive signal selection circuit 200-1 and the connector 350, there are other nozzle rows L2 to L6 and nozzle rows L2 to L6. The piezoelectric element 60 included in each is not positioned. In other words, the nozzle row L1 is located closest to the connector 350 among the nozzle rows L1 to L6 formed on the ink ejection surface 311. FIG.

In other words, the print head 21 has a plurality of flexible wiring boards 335 electrically connected to the substrate 320, and the shortest distance between the flexible wiring boards 335 corresponding to the nozzle row L1 and the connector 350 is the nozzle row L2. is shorter than the shortest distance between the connector 350 and the flexible wiring board 335 corresponding to . Furthermore, the flexible wiring board 335 corresponding to the nozzle row L1 is provided closest to the connector 350 among the plurality of flexible wiring boards 335 of the print head 21 . Here, the flexible wiring board 335 corresponding to the nozzle row L1 is an example of a first wiring board, the flexible wiring board 335 corresponding to the nozzle row L2 is an example of a second wiring board, and the flexible wiring board 335 corresponding to the nozzle row L1 is an example of a second wiring board. The plurality of flexible wiring boards 335 including the wiring boards 335 and the flexible wiring boards 335 corresponding to the nozzle row L2 is an example of the plurality of wiring boards.

In the print head 21 configured as described above, the drive signals COM1 to COM6, the reference voltage signals CGND1 to CGND6, the setting signals TD1 to TD6, the latch signal LAT, the change signal CH, and the clock input through the connectors 350 and 360 are input. A plurality of signals including signal SCK are input to flexible wiring board 335 connected to each of electrode groups 330a to 330f.

Specifically, as shown in FIG. 18, a flexible wiring board 335 is inserted through the FPC insertion hole 332 . The flexible wiring board 335 has one end A section connected to the electrode group 330 and the other end B section connected to one end of the electrode wiring 337 . The other end of the electrode wiring 337 is connected to the electrode 611 of the piezoelectric element 60 . That is, the electrode wiring 337 is provided in the same number as the ejection portions 600 . Also, the integrated circuit 201 is mounted on the flexible wiring board 335 by COF (Chip On Film). In other words, the printhead 21 has an integrated circuit 201 and the integrated circuit 201 is provided on the flexible wiring substrate 335 . This integrated circuit 201 includes a drive signal selection circuit 200 and a temperature abnormality detection circuit 250 . By inputting the setting signal TD1, the change signal cCH, the latch signal cLAT, the clock signal cSCK, and the drive signal COM to the integrated circuit 201 via the electrode group 330, the drive signal included in the integrated circuit 201 is selected. Circuit 200 generates a drive signal VOUT. The integrated circuit 201 supplies the generated drive signal VOUT to the electrode 611 of the piezoelectric element 60 corresponding to each of the ejection portions 600 via the electrode wiring 337 . Although not shown in FIG. 18, the integrated circuit 241 is provided on the first surface 321 of the substrate 320 in a space formed between the substrate 320 and the head 310 . The space may be, for example, a space formed by supporting the substrate 320 by a fixing member inserted through the fixing portions 347 to 349, and the head 310 fixes the substrate 320. It may be a space formed by having a concave portion on a part of the surface.

Here, connector 350 is an example of a connector, and integrated circuit 241 including diagnostic circuit 240 is an example of a first integrated circuit. The board 320 provided with the connector 350 and the integrated circuit 241 is an example of a circuit board. The connector 350 and the integrated circuit 241 are provided on the first surface 321 of the substrate 320 as shown in FIG. In other words, connector 350 and integrated circuit 241 are provided on the same side of substrate 320 . Also, the integrated circuit 201 including the drive signal selection circuit 200 is an example of the second integrated circuit.

1.7 Details of Signals Input to Print Head Details of signals input to the print head 21 in the liquid ejection apparatus 1 configured as described above will be described with reference to FIGS. 19 and 20. FIG.

FIG. 19 is a diagram for explaining the details of signals input to connector 350. As shown in FIG. As shown in FIG. 19, the connector 350 has terminals to which drive signals COM1 to COM6 are input, terminals to which reference voltage signals CGND1 to CGND6 are input, temperature signal TH, latch signal LAT, and clock signal. a terminal to which SCK, a change signal CH, a setting signal TD1, and an abnormal signal XHOT are input; a terminal to which diagnostic signals DIG-A to DIG-E are input; a terminal to which a voltage VHV is input; and a plurality of terminals to which a plurality of ground signals GND are input.

Specifically, the drive signals COM1 to COM6 are input from terminals 353-11, 353-9, 353-7, 353-5, 353-3, and 353-1, respectively. Also, the reference voltage signals CGND1 to CGND6 are input from terminals 353-12, 353-10, 353-8, 353-6, 353-4 and 353-2, respectively.

Diagnostic signal DIG-A is input from terminal 353-23. Similarly, the latch signal LAT is input from the terminal 353-23. That is, the terminal 353-23 serves as both a terminal to which the diagnostic signal DIG-A is input and a terminal to which the latch signal LAT is input. Here, the terminal 353-23 serving both as a terminal to which the diagnostic signal DIG-A is input and a terminal to which the latch signal LAT is input is an example of the second terminal.

Diagnosis signal DIG-B is input from terminal 353-21. Similarly, the clock signal SCK is input from the terminal 353-6. That is, the terminal 353-21 serves as both a terminal to which the diagnostic signal DIG-B is input and a terminal to which the clock signal SCK is input. Here, the terminal 353-21 serving both as a terminal to which the diagnostic signal DIG-B is input and a terminal to which the clock signal SCK is input is an example of the fourth terminal.

Diagnostic signal DIG-C is input from terminal 353-19. Similarly, the change signal CH is input from the terminal 353-19. That is, the terminal 353-19 serves both as a terminal to which the diagnostic signal DIG-C is input and a terminal to which the change signal CH is input. Here, the terminal 353-19 serving both as a terminal to which the diagnostic signal DIG-C is input and a terminal to which the change signal CH is input is an example of a third terminal.

Diagnostic signal DIG-D is input from terminal 353-17. Similarly, the setting signal TD1 is input to the terminal 353-17. That is, the terminal 353-17 serves both as a terminal to which the diagnostic signal DIG-D is input and a terminal to which the setting signal TD1 is input. Here, the terminal 353-17 serving both as a terminal to which the diagnostic signal DIG-D is input and a terminal to which the setting signal TD1 is input is an example of the first terminal.

The diagnostic signal DIG-E and the abnormality signal XHOT output from the integrated circuit 241 including the diagnostic circuit 240 are input to the terminal 353-15. That is, the terminal 353-15 serves both as a terminal to which the diagnostic signal DIG-E is input and a terminal to which the abnormal signal XHOT is input.

As described above, in the first embodiment, each of the diagnostic signals DIG-A to DIG-E and each of the latch signal LAT, the clock signal SCK, the change signal CH, the setting signal TD1, and the abnormality signal XHOT are common. input to the terminal. Here, an example of a method of inputting each of the diagnostic signals DIG-A to DIG-E and each of the latch signal LAT, clock signal SCK, change signal CH, setting signal TD1, and abnormality signal XHOT to a common terminal will be described. do.

For example, the control circuit 100 outputs the diagnostic signal DIG-A and the latch signal LAT, the diagnostic signal DIG-B and the clock signal SCK, the diagnostic signal DIG-C and the change signal, according to the operating states of the liquid ejection device 1 and the print head 21. CH, diagnosis signal DIG-D and setting signal TD1 are generated in a time division manner. Specifically, when the liquid ejection device 1 is in a printing state in which ink is ejected, the control circuit 100 generates a latch signal LAT, a clock signal SCK, a change signal CH, and a setting signal TD1 and outputs them to the print head 21 . do. In addition, when the print head 21 performs self-diagnosis, not in a printing state where the liquid ejection device 1 ejects ink, the control circuit 100 generates diagnostic signals DIG-A to DIG-D and outputs them to the print head 21 . . As a result, the latch signal LAT, the clock signal SCK, the change signal CH, the setting signal TD1, and the diagnostic signals DIG-A to DIG-D are input to the print head 21 after propagating through common wiring. be. That is, the latch signal LAT, the clock signal SCK, the change signal CH, the setting signal TD1, and the diagnosis signals DIG-A to DIG-D are input to common terminals.

As a method of inputting the diagnostic signal DIG-E and the abnormal signal XHOT to a common terminal, for example, when the diagnostic signals DIG-A to DIG-D are input, the diagnostic circuit 240 outputs the diagnostic signal DIG- When the diagnostic signal DIG-E indicating the diagnostic result based on A to DIG-D is output, and the latch signal LAT, clock signal SCK, change signal CH, and setting signal TD1 are input, the diagnostic circuit 240 detects temperature abnormality. An abnormality signal XHOT based on the abnormality signal cXHOT indicating the detection result of the temperature abnormality by the detection circuit 250 is output. The diagnostic circuit 240 inputs the diagnostic signal DIG-E and the abnormal signal XHOT to a common terminal. If at least one of the results is abnormal, a signal indicating that normal ejection of ink from the print head 21 is not possible is input to the relevant terminal, and whether the temperature in the temperature abnormality detection circuit 250 is abnormal. and the diagnosis by the diagnostic circuit 240 are normal, a signal indicating that the print head 21 can eject ink normally is input to the terminal.

A method of inputting each of the diagnostic signals DIG-A to DIG-E described above and each of the latch signal LAT, the clock signal SCK, the change signal CH, the setting signal TD1, and the abnormality signal XHOT to a common terminal of the connector 350. is an example, and for example, a selector or the like may be used to switch between a signal propagated through wiring and a signal input to a terminal.

The setting signal TD, the change signal CH, the latch signal LAT, the clock signal SCK, and the error signal XHOT are important signals for controlling the ejection of the print head 21. If there is a connection failure in the wiring through which these signals are propagated, the signal may be damaged. If this occurs, there is a risk that the ink ejection accuracy will be degraded. The wiring through which such an important signal propagates and the wiring through which the signal for self-diagnosis by the print head 21 is propagated are used as common wiring, and the terminal to which the signal is input and the signal for the self-diagnosis of the print head 21 are input. By using the terminal to be connected as a common terminal, based on the result of the self-diagnosis of the print head 21, the setting signal TD1, the change signal CH, and the latch signal LAT
, the clock signal SCK, and the abnormal signal XHOT are normally propagated. Furthermore, since a plurality of signals are propagated through one wiring and a plurality of signals are input to one terminal, the number of wirings to be provided in the cable as a propagation path and the number of terminals provided in the connector 350 are reduced. is also possible.

Temperature signal TH is input to terminal 353-25. Also, the voltage VHV is input to the terminal 353-13. Also, the ground signal GND is input to each of terminals 353-14, 353-16, 353-18, 353-20, 353-22, 353-24 and 353-26.

Next, the details of the signal input to connector 360 will be described with reference to FIG. FIG. 20 is a diagram for explaining the details of the signal input to connector 360. As shown in FIG. As shown in FIG. 20, connector 360 has terminals to which drive signals COM1 to COM6 are input, terminals to which reference voltage signals CGND1 to CGND6 are input, and setting signals TD2 to TD6. terminals to which voltages VHV, VDD1 and VDD2 are input, and a plurality of terminals to which a plurality of ground signals GND are input.

Specifically, the drive signals COM1 to COM6 are input from terminals 363-12, 363-10, 363-8, 363-6, 363-4, and 363-2, respectively. Further, reference voltage signals CGND1 to CGND6 are input from terminals 363-11, 363-9, 363-7, 363-5, 363-3 and 363-1, respectively.

Setting signals TD2 to TD6 are input from terminals 363-24, 363-22, 363-20, 363-18 and 363-16, respectively. Also, voltage VDD1 is input from terminal 363-26, and voltage VDD2 is input from terminal 363-21.

A ground signal GND is input to each of terminals 353-13, 353-14, 353-15, 353-17, 353-19, 353-23 and 353-25.

1.8 Wiring Pattern Formed on Print Head Here, using FIG. will be explained. FIG. 21 is a diagram showing an example of wiring formed on the first surface 321 of the substrate 320. As shown in FIG. Note that in FIG. 21, illustration of part of the wiring formed on the substrate 320 is omitted. Also, in FIG. 21, electrode groups 330a to 330f formed on the second surface 322 of the substrate 320 are indicated by broken lines.

As shown in FIG. 21, substrate 320 has wires 354-a through 354-p.

The terminal 353-23 is electrically connected to the wiring 354-a. The diagnostic signal DIG-A and the latch signal LAT input from the terminal 353-23 are input to the integrated circuit 241 after propagating through the wiring 354-a. That is, the wiring 354-a electrically connects the terminal 353-23 and the integrated circuit 241. FIG. The wiring 354-a through which the diagnosis signal DIG-A and the latch signal LAT propagate is an example of the second wiring.

The terminal 353-21 is electrically connected to the wiring 354-b. The diagnostic signal DIG-B and the clock signal SCK input from the terminal 353-21 are input to the integrated circuit 241 after propagating through the wiring 354-b. That is, the wiring 354-b electrically connects the terminal 353-21 and the integrated circuit 241. FIG. This diagnostic signal DIG-B and the clock signal SCK
The wiring 354-b that propagates is an example of the fourth wiring.

The terminal 353-19 is electrically connected to the wiring 354-c. The diagnostic signal DIG-C and the change signal CH input from the terminal 353-19 are input to the integrated circuit 241 after propagating through the wiring 354-c. That is, the wiring 354-c electrically connects the terminal 353-19 and the integrated circuit 241. FIG. The wiring 354-c through which the diagnosis signal DIG-C and the change signal CH propagate is an example of the third wiring.

The terminal 353-17 is electrically connected to the wiring 354-d. The diagnostic signal DIG-D and the setting signal TD1 input from the terminal 353-17 are input to the integrated circuit 241 after propagating through the wiring 354-d. That is, the wiring 354-d electrically connects the terminal 353-17 and the integrated circuit 241. FIG. The wiring 354-d through which the diagnosis signal DIG-D and the setting signal TD1 propagate is an example of the first wiring.

The terminal 353-15 is electrically connected to the wiring 354-e. The diagnostic signal DIG-E and the abnormal signal XHOT output from the integrated circuit 241 are input to the terminal 353-15 after propagating through the wiring 354-e. That is, the wiring 354 - e electrically connects the terminal 353 - 15 and the integrated circuit 241 .

Here, it is preferable that vias or the like are not formed in each of the wirings 354-a to 354-d that propagate the diagnostic signals DIG-A to DIG-D, respectively. Connector 350 and integrated circuit 241 forming diagnostic circuit 240 are preferably provided on first surface 321 , which is the same surface of substrate 320 . Each of the diagnostic signals DIG-A to DIG-D is a signal for diagnosing whether or not the integrated circuit 241 can eject ink normally. Therefore, if the diagnostic signals DIG-A to DIG-D interfere with the surrounding noise when the diagnostic signals DIG-A to DIG-D are propagated, the integrated circuit 241 cannot perform the diagnosis normally, and as a result, the print head 21 There is a risk that the ejection accuracy of the ink will deteriorate. By not providing vias or the like in the wirings 354-a to 354-d that propagate the diagnostic signals DIG-A to DIG-D, respectively, there is a risk that noise noise will interfere with the diagnostic signals DIG-A to DIG-D. can be reduced.

When the diagnosis circuit 240 included in the integrated circuit 241 diagnoses that ink can be discharged normally from the print head 21 based on the diagnosis signals DIG-A to DIG-D, the integrated circuit 241 outputs the latch signal LAT, The clock signal SCK and change signal CH are output to the drive signal selection circuit 200 as the latch signal cLAT, clock signal cSCK and change signal cCH. Specifically, the change signal cCH, the clock signal cSCK, and the latch signal cLAT output from terminals (not shown) of the integrated circuit 241 propagate through the wirings 354-f to 354-h, and then pass through the flexible wiring board 335. input to the drive signal selection circuit 200. That is, the wirings 354-f to 354-h electrically connect the integrated circuit 241 and the flexible wiring board 335. FIG. At least one of the wirings 354-f to 354-h through which the change signal cCH, the clock signal cSCK, and the latch signal cLAT propagate is an example of the sixth wiring.

Specifically, the integrated circuit 241 forming the diagnostic circuit 240 is electrically connected to the wiring 354-f. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 354-f is electrically connected to the wiring 354-c through the integrated circuit 241. FIG. As a result, the change signal cCH based on the change signal CH is input to the wiring 354-f. The change signal cCH is input to one of the electrodes included in the electrode group 330a provided on the second surface 322 of the substrate 320 via the wiring 354-f and vias (not shown). The change signal cCH is input to the drive signal selection circuit 200-1 via the flexible wiring board 335 connected to the electrode group 330a. That is, the wiring 354-f electrically connects the integrated circuit 241 and the drive signal selection circuit 200-1 via the flexible wiring board 335. FIG.

In addition, the integrated circuit 241 is electrically connected to the wiring 354-g. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 354-g is electrically connected to the wiring 354-b through the integrated circuit 241. FIG. Accordingly, the clock signal cSCK based on the clock signal SCK is input to the wiring 354-g. The clock signal cSCK is input to one of a plurality of electrodes included in the electrode group 330a provided on the second surface 322 of the substrate 320 via the wiring 354-g and vias (not shown). The clock signal cSCK is input to the drive signal selection circuit 200-1 through the flexible wiring board 335 connected to the electrode group 330a. That is, the wiring 354-g electrically connects the integrated circuit 241 and the drive signal selection circuit 200-1 via the flexible wiring board 335. FIG.

In addition, the integrated circuit 241 is electrically connected to the wiring 354-h. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 354-h is electrically connected to the wiring 354-a via the integrated circuit 241. FIG. Accordingly, the latch signal cLAT based on the latch signal LAT is input to the wiring 354-h. The latch signal cLAT is input to one of a plurality of electrodes included in the electrode group 330a provided on the second surface 322 of the substrate 320 via wiring 354-h and vias (not shown). The latch signal cLAT is input to the drive signal selection circuit 200-1 through the flexible wiring board 335 connected to the electrode group 330a. That is, the wiring 354-h electrically connects the integrated circuit 241, the drive signal selection circuit 200-1, and the flexible wiring board 335. FIG.

21, only wirings 354-f to 354-h through which the latch signal cLAT, clock signal cSCK, and change signal cCH that are input to the drive signal selection circuit 200-1 are shown. Wiring through which the latch signal cLAT, the clock signal cSCK, and the change signal cCH input to 200-2 to 200-6 propagate is omitted.

In addition, one of the electrodes included in the electrode group 330a and a terminal (not shown) of the integrated circuit 241 are electrically connected to each other through a wiring 354-p. An abnormality signal cXHOT output from the temperature abnormality detection circuit 250 propagates through the wiring 354-p. The abnormal signal cXHOT is then input to the integrated circuit 241 .

Furthermore, as shown in FIG. 21, the terminal 353-17 is also electrically connected to the wiring 354-i. The setting signal TD1 input from the terminal 353-17 propagates through the wiring 354-i, and then passes through vias (not shown) to a plurality of electrodes included in the electrode group 330a provided on the second surface 322 of the substrate 320. connected to one of the electrodes. The wiring 354-i is input to the drive signal selection circuit 200 via the flexible wiring board 335 electrically connected to the electrode group 330a. That is, the wiring 354-i electrically connects the terminal 353-17 and the flexible wiring board 335. FIG. The wiring 354-i through which the setting signal TD1 propagates is an example of the fifth wiring.

As described above, by dividing the wiring 354-d for propagating the setting signal TD to the integrated circuit 241 and the wiring 354-i for propagating the setting signal TD to the drive signal selection circuit 200 via the flexible wiring board 335, the setting signal TD can be It is possible to reduce the risk of signal delay and waveform distortion caused by the integrated circuit 241 . As described above, the frequency of the setting signal TD is higher than the frequencies of the latch signal LAT and the change signal CH. In other words, the frequency of the setting signal TD propagating through the wiring 354-d and the wiring 354-i is higher than the frequency of the change signal CH propagating through the wiring 354-c and the latch signal LAT propagating through the wiring 354-a. expensive. If signal delay and waveform distortion occur in such a high-frequency setting signal TD, the ink ejection accuracy is greatly affected. That is, by branching the wiring for propagating the setting signal TD having a higher frequency than the change signal CH propagating on the wiring 354-c and the latch signal LAT propagating on the wiring 354-a at the substrate 320 of the print head 21, This reduces the risk of signal delay and waveform distortion occurring in the setting signal TD, making it possible to improve ink ejection accuracy.

The clock signal SCK is a signal with a monotonous repetition period, whereas the setting signal TD has different logic levels depending on the data included in the setting data signal SP and the print data signal SI. Therefore, when the setting signal TD is delayed and the waveform is distorted, there is a high possibility that the ink ejection accuracy will be lowered. That is, by branching the wiring for propagating the setting signal TD on the substrate 320 of the print head 21, ink ejection accuracy can be improved in the case where the change signal CH, the clock signal SCK, and the latch signal LAT are branched. It is possible to obtain a higher effect of

A terminal 353-11 to which the drive signal COM1 is input is electrically connected to the wiring 354-j. After being propagated through the wiring 354-j, the drive signal COM1 is input to one of the electrodes included in the electrode group 330a provided on the second surface 322 of the substrate 320 via vias (not shown). be done. The drive signal COM1 is input to the drive signal selection circuit 200-1 through the flexible wiring board 335 connected to the electrode group 330a. That is, the wiring 354-j electrically connects the terminal 353-11 and the driving signal selection circuit 200-1.

Similarly, terminals 353-9, 353-7, 353-5, 353-3, and 353-1 to which drive signals COM2 to COM6 are input are electrically connected to wirings 354-k to 354-o, respectively. It is connected. Then, after each of the drive signals COM2 to COM6 propagates through the wirings 354-k to 354-o, the electrode groups 330b to 330f provided on the second surface 322 of the substrate 320 through vias (not shown). It is input to any one of a plurality of electrodes included in each.

As described above, the substrate 320 has wirings 354-a to 354-p, and various signals inputted from the connector 350 are propagated to the flexible wiring substrate 335. FIG. Here, the configuration of the flexible wiring board 335 will be described with reference to FIG. 22 . FIG. 22 is a diagram showing the configuration of the flexible wiring board 335. As shown in FIG.

As shown in FIG. 22, the drive signal selection circuit 200 which is an integrated circuit 201 is mounted on the flexible wiring board 335 . A plurality of wirings 341 and a plurality of wirings 342 are formed on the flexible wiring board 335 . One end of the plurality of wirings 341 is electrically connected to the integrated circuit 201 and the other end is electrically connected to the electrode group 330 provided on the substrate 320 in the A portion. One end of the plurality of wirings 342 is electrically connected to the integrated circuit 201, and the other end is electrically connected to the electrode wiring 337 in the B section.

Various signals propagated through the substrate 320 are input to the flexible wiring substrate 335 via the A portion of the flexible wiring substrate 335 electrically connected to the electrode group 330 . Then, the signal input to the flexible wiring board 335 propagates through a plurality of wirings 341 and is input to the integrated circuit 201 . The integrated circuit 201 generates and outputs the drive signal VOUT in the drive signal selection circuit 200 included in the integrated circuit 201 . A driving signal VOUT output from the integrated circuit 201 is propagated through a plurality of wirings 342 and supplied to the corresponding piezoelectric elements 60 via the electrode wirings 337 .

That is, the flexible wiring board 335 includes the same number of wirings 341 as the number of signals input from the board 320 , that is, the number of electrodes formed in the electrode group 330 , and a plurality of discharge sections 600 corresponding to the drive signal selection circuit 200 . has the same number of wirings 342 as the number of . Therefore, the total number of wirings 341 that the flexible wiring board 335 has is less than the total number of wirings 342 . Therefore, the number of electrodes arranged in the A section electrically connecting the wiring 341 of the flexible wiring board 335 and the substrate 320 is larger than the number of electrodes arranged in the B section electrically connecting the wiring 342 and the electrode wiring 337 . few. Therefore, the spacing and pitch between the electrodes in the A section is wider than the spacing between the electrodes in the B section. For example, the spacing between the electrodes in the B section is 30 μm, while the spacing between the electrodes in the A section is 400 μm.

Here, among the plurality of wirings 341, the wiring 341 electrically connecting the wiring 354-i through which the setting signal TD1 propagates to the integrated circuit 201 and through which the setting signal TD1 propagates is an example of the seventh wiring, electrically connecting one of the wirings 354-f to 354-h to the integrated circuit 201;
A wiring 341 that propagates at least one of the change signal cCH, the clock signal cSCK, and the latch signal cLAT is an example of the eighth wiring.

In addition, the flexible wiring board 335 propagates the signal propagated by the substrate 320 to the integrated circuit 201 on which the drive signal selection circuit 200 is mounted, and further, the drive signal VOUT output by the drive signal selection circuit 200 is transferred to a plurality of corresponding signals. It is sufficient that wiring for supplying to the ejection portion 600 is provided, and a different configuration may be used. However, as shown in the present embodiment, by using a flexible wiring board as the base, it becomes possible to flexibly cope with the interval between nozzle rows and the number of ejection portions 600, and the versatility of the print head 21 is improved. can be increased.

1.9 Functions and Effects As described above, the liquid ejection device 1 and the print head 21 according to the present embodiment are connected to the connector 350 for inputting various signals to the print head 21 and for outputting various signals from the print head 21. , an integrated circuit 241, a connector 350, and a substrate 320 on which the integrated circuit 241 is provided.

The substrate 320 includes wiring 354-d electrically connecting the integrated circuit 241 and the terminal 353-17 of the connector 350, and wiring 354-a electrically connecting the integrated circuit 241 and the terminal 353-23 of the connector 350. , a wiring 354-c electrically connecting the integrated circuit 241 and the terminal 353-19 of the connector 350, and a wiring 354-b electrically connecting the integrated circuit 241 and the terminal 353-21 of the connector 350. have. That is, the signals input to the print head 21 from the terminals 353-17, 353-23, 353-19, 353-21 of the connector 350 are connected to the wirings 354-d, 354-a, 354-c, 354-b. is propagated and input to the integrated circuit 241 .

Further, the substrate 320 has a wiring 354-i that electrically connects the terminal 353-17 of the connector 350 and the flexible wiring substrate 335. FIG. That is, among the signals input to the print head 21 from the connector 350, the signal input from the terminal 353-17 is branched at the substrate 320, and one of the branched signals propagates through the wiring 354-d to the integrated circuit 241. , and the other branched signal propagates through the wiring 354-i and is input to the flexible wiring board 335. FIG.

In general, an integrated circuit device such as the integrated circuit 241 executes various kinds of processing such as arithmetic processing and determination processing based on an input signal, and outputs a signal based on the result of the processing. Therefore, the integrated circuit device includes a circuit for executing the processing. Therefore, signals propagating through the integrated circuit device are more likely to experience signal delay and waveform distortion.

On the other hand, in the liquid ejection device 1 and the print head 21 according to this embodiment, the signal input to the print head 21 from the terminal 353 - 17 of the connector 350 is branched at the substrate 320 . One branched signal propagates through the wiring 354 - d and is input to the integrated circuit 241 , and the other branched signal propagates through the wiring 354 - i and is input to the flexible wiring board 335 . Therefore, the flexible wiring board 335 receives a signal with reduced risk of signal delay and waveform distortion due to the configuration of the integrated circuit 241 .

Therefore, the integrated circuit 241 has a self-diagnosis function, and the driving signal selection circuit 200 electrically connected to the flexible wiring board 335 ejects ink from the nozzle 651 based on the signal input to the flexible wiring board 335. In this case, the signal input to the flexible wiring board 335 is less likely to suffer signal delay and waveform distortion due to the integrated circuit 241 for executing the self-diagnostic function. Therefore, in the liquid ejecting apparatus 1 and the print head 21 according to the present embodiment, even when the signal for executing the self-diagnostic function and the signal for executing the printing process are propagated through a common signal path, By inputting the signal to the terminal 353-17 of the connector 350, the self-diagnostic function of the print head 21 can be normally executed, and the possibility of deterioration of the ejection accuracy of the ink ejected from the nozzles 651 can be reduced to perform the printing process. can be compatible with executing

Further, in the liquid ejection device 1 and the print head 21 according to the present embodiment, even if the integrated circuit 201 for controlling ejection of ink from the nozzles 651 is mounted on the flexible wiring board 335, the flexible Since the wiring substrate 335 receives a signal that is less likely to cause signal delay and waveform distortion due to the configuration of the integrated circuit 241, the signal input to the integrated circuit 201 has a self-diagnostic function. signal delay and waveform distortion caused by the integrated circuit 241 for executing the are reduced.

Further, in the liquid ejection device 1 and the print head 21 according to this embodiment, the connector 350 and the integrated circuit 241 are provided on the same surface of the substrate 320 . As a result, inputs from terminals 353-17, 353-23, 353-19, and 353-21 of connector 350 are propagated through wires 354-d, 354-a, 354-c, and 354-b, and the integrated circuit 241 is less likely to be superimposed with noise or the like. Therefore, the accuracy of processing such as arithmetic processing and determination processing executed in the integrated circuit 241 is improved. That is, when the integrated circuit 241 has a self-diagnosis function, it is possible to improve the accuracy of self-diagnosis in the integrated circuit 241 . Therefore, it is possible to further improve the accuracy of the self-diagnostic function of the print head 21 executed in the integrated circuit 241 and to reduce the risk of ink ejection accuracy deterioration while executing the printing process.

Further, in the liquid ejection device 1 and the print head 21 according to the present embodiment, when the print head 21 has a plurality of flexible wiring boards 335, the wiring 354-i electrically connected to the terminal 353-17 is connected to the terminal 353 -17 is electrically connected to the flexible printed circuit board 335 closest to the connector 350 containing the -17.

When the wiring that propagates the signal input from the terminal 353-17 is branched, the wiring length becomes longer than when the wiring is not branched. Therefore, there is an increased possibility that external noise or the like will interfere with the wiring through which the signal is propagated. In the liquid ejecting apparatus 1 and the print head 21 of this embodiment, the flexible wiring board 335 electrically connected to one of the wirings 354-i branched from the board 320 is the flexible wiring board 335 closest to the connector 350. By doing so, it is possible to reduce the increase in the wiring length of the wiring 354-i. Therefore, the possibility of external noise interfering with the wiring 354-i is reduced. Therefore, it is possible to reduce the possibility that external noise interferes with the signal input from the terminal 353-17 and that the waveform of the signal is distorted. It is possible to improve accuracy and further reduce the risk of deterioration in ink ejection accuracy.

In addition, as shown in this embodiment, in the liquid ejection device 1 and the print head 21, self-diagnosis of the print head 21 may be performed by a plurality of signals input to the integrated circuit 241. The frequency of the signal input to terminal 353-17 is preferably higher than the frequency of the signals input to terminals 353-19 and 353-23. In other words, the frequency of the setting signal TD propagating through the wiring 354-d electrically connecting the terminal 353-17 and the integrated circuit 241 is adjusted to the frequency of the wiring 354-c electrically connecting the terminal 353-19 and the integrated circuit 241. , and preferably higher than the frequency of the latch signal LAT propagating through the wiring 354-a that electrically connects the terminal 353-23 and the integrated circuit 241. FIG. In other words, among the signals input to the print head 21, the frequency of the signal branched by the substrate 320 is preferably high.

When signal delay and waveform distortion occur in the integrated circuit 241 , the signal delay time and the amount of waveform distortion contribute to the circuit configuration of the integrated circuit 241 . That is, regardless of the frequency of the signal input to the integrated circuit 241, the delay time and distortion amount may be substantially the same. Therefore, when signal delay and waveform distortion occur in the integrated circuit 241, the higher the frequency of the signal input to the integrated circuit 241, the greater the effect. Therefore, by making the frequency of the signal input to the terminal 353-17 of the connector 350 higher than the frequency of the signal input to the terminals 353-19 and 353-23, the liquid ejecting apparatus 1 and the print head 21 It is possible to reduce the effects of signal delay and waveform distortion occurring in the integrated circuit 241 . As a result, it is possible to reduce the risk of deterioration in ink ejection accuracy due to signal delay and waveform distortion caused by the integrated circuit 241 for executing the self-diagnostic function.

2. Second Embodiment Next, a liquid ejection device 1 and a print head 21 according to a second embodiment will be described. In describing the liquid ejection device 1 and the print head 21 of the second embodiment, the same reference numerals are given to the same configurations as in the first embodiment, and the description thereof will be omitted or simplified.

FIG. 23 is a block diagram showing the electrical configuration of the liquid ejection device 1 according to the second embodiment. As shown in FIG. 23, the control circuit 100 in the second embodiment includes two latch signals LAT1 and LAT2 that define the ejection timing of the print head 21, and two change signals that define the waveform switching timing of the drive signal COM. It differs from the first embodiment in that CH1, CH2 and two clock signals SCK1, SCK2 for defining the timing at which the setting signal TD is input are generated and output to the print head 21. FIG. Further, the control circuit 100 generates diagnostic signals DIG-A to DIG-D and DIG-F to DIG-I for diagnosing whether or not the print head 21 is capable of normal ejection of liquid. , which is different from the first embodiment.

Here, in the liquid ejecting apparatus 1 according to the second embodiment, the diagnostic signal DIG-A and the latch signal LAT1, the diagnostic signal DIG-B and the clock signal SCK1, the diagnostic signal DIG-C and the change signal CH1, the diagnostic signal DIG-D and The setting signal TD1, the diagnostic signal DIG-F and the latch signal LAT2, the diagnostic signal DIG-G and the clock signal SCK2, the diagnostic signal DIG-H and the change signal CH2, and the diagnostic signal DIG-I and the setting signal TDn each propagate in common. It is output via a path to diagnostic circuitry 240 included in printhead 21 .

The diagnostic circuit 240 diagnoses whether ink can be ejected normally based on the diagnostic signals DIG-A to DIG-D and DIG-F to DIG-I. When the diagnostic circuit 240 determines that ink can be discharged normally from the print head 21 based on the diagnostic signals DIG-A to DIG-D, the diagnostic signals DIG-A to DIG-C are transmitted in common. The latch signal LAT1, the clock signal SCK1 and the change signal CH1 input through the path are output as the latch signal cLAT1, the clock signal cSCK1 and the change signal cCH1. Further, when the diagnostic circuit 240 determines that the print head 21 can eject ink normally based on the diagnostic signals DIG-F to DIG-I, the diagnostic signals DIG-F to DIG-H and the common propagation of the diagnostic signals DIG-F to DIG-H. The latch signal LAT2, clock signal SCK2, and change signal CH2 input through the path are output as the latch signal cLAT2, clock signal cSCK2, and change signal cCH2.

Among the signals input to the diagnostic circuit 240, the setting signal TD1, which is input via a common propagation path with the diagnostic signal DIG-D, is branched at the print head 21, and one of the branched signals is It is input to the diagnostic circuit 240, and the other signal is input to the drive signal selection circuit 200-1. Among the signals input to the diagnostic circuit 240, the setting signal TDn, which is input through the same propagation path as the diagnostic signal DIG-I, is branched in the print head 21, and one of the branched signals is the diagnostic signal. It is input to the circuit 240, and the other signal is input to the drive signal selection circuit 200-n.

In the following description, it is assumed that the print head 21 in the second embodiment has 10 drive signal selection circuits 200-1 to 200-10. Therefore, the print head 21 in the second embodiment has 10 setting signals TD1 to TD10 corresponding to the 10 drive signal selection circuits 200-1 to 200-10, and 10 drive signals COM1 to COM10. , and 10 reference voltage signals CGND1 to CGND10 are input.

FIG. 24 is a perspective view showing the configuration of the print head 21 in the second embodiment. As shown in FIG. 24, print head 21 has head 310 and substrate 320 . An ink ejection surface 311 having a plurality of ejection portions 600 formed thereon is positioned on the lower surface of the head 310 in the Z direction.

FIG. 25 is a plan view showing the configuration of the ink ejection surface 311 of the head 310 in the second embodiment. As shown in FIG. 25, ten nozzle plates 632 each having a plurality of nozzles 651 are arranged in the X direction on the ink ejection surface 311 of the second embodiment. In each of the nozzle plates 632, nozzle rows L1 to L10 are formed in which the nozzles 651 are arranged in the X direction. Each of the nozzle rows L1 to L10 is provided corresponding to each of the drive signal selection circuits 200-1 to 200-10. That is, the plurality of piezoelectric elements 60 included in each of the nozzle rows L1 to L10 form a plurality of piezoelectric element groups.

Returning to FIG. 24, the substrate 320 has a first surface 321 and a second surface 322 facing the first surface 321, and a first side 323 and a second side facing the first side 323 in the X direction. It has a substantially rectangular shape formed by two sides 324, a third side 325, and a fourth side 326 facing the third side 325 in the Y direction.

The configuration of the substrate 320 in the second embodiment will be described with reference to FIGS. 26 and 27. FIG. FIG. 26 is a plan view of the substrate 320 viewed from the second surface 322 in the second embodiment. Also, FIG. 27 is a plan view of the substrate 320 in the second embodiment when viewed from the first surface 321. As shown in FIG.

As shown in FIGS. 26 and 27, the second surface 322 of the substrate 320 is provided with electrode groups 430a to 430j. Each of the electrode groups 430a to 430j has a plurality of electrodes arranged side by side in the Y direction. The electrode groups 430a to 430j are positioned in the order of electrode groups 430a, 430b, 430c, 430d, 430e, 430f, 430g, 430h, 430i, 430j from the first side 323 side toward the second side 324 side. there is Here, each of the electrode groups 430a-430j has the same configuration as each of the electrode groups 330a-330f in the first embodiment.

Further, the substrate 320 is formed with ink supply path insertion holes 431a to 431j and FPC insertion holes 432a to 432e, which are through holes penetrating the first surface 321 and the second surface 322 of the substrate 320. FIG.

The FPC insertion hole 432a is located between the electrode group 430a and the electrode group 430b in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 430a and the electrode group 430b. The flexible wiring board 335 is inserted. The FPC insertion hole 432b is located between the electrode group 430c and the electrode group 430d in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 430c and the electrode group 430d. The flexible wiring board 335 is inserted. The FPC insertion hole 432c is located between the electrode group 430e and the electrode group 430f in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 430e and the electrode group 430f. The flexible wiring board 335 is inserted. The FPC insertion hole 432d is positioned between the electrode group 430g and the electrode group 430h in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 430g and the electrode group 430h. The flexible wiring board 335 is inserted. The FPC insertion hole 432e is located between the electrode group 430i and the electrode group 430j in the X direction, and is electrically connected to the flexible wiring board 335 electrically connected to the electrode group 430i and the electrode group 430j. The flexible wiring board 335 is inserted.

The ink supply path insertion hole 431a is located on the first side 323 side of the electrode group 430a in the X direction. The ink supply path insertion holes 431b and 431c are located between the electrode group 430b and the electrode group 430c in the X direction. They are located side by side so as to be on the 326 side. The ink supply path insertion holes 431d and 431e are located between the electrode group 430d and the electrode group 430e in the X direction. They are located side by side so as to be on the 326 side. The ink supply path insertion holes 431f and 431g are located between the electrode group 430f and the electrode group 430g in the X direction. They are located side by side so as to be on the 326 side. The ink supply path insertion holes 431h and 431i are located between the electrode group 430h and the electrode group 430i in the X direction. They are located side by side so as to be on the 326 side. The ink supply path insertion hole 431j is positioned on the second side 324 side of the electrode group 430j in the X direction. In each of the ink supply passage insertion holes 431a to 431j, an ink supply port 661 for introducing ink to the ejection portion 600 corresponding to each of the nozzle rows L1 to L10 and a part of an ink supply passage (not shown) inserted therein. is inserted.

Here, each of the ink supply path insertion holes 431a to 431j has the same configuration as each of the ink supply path insertion holes 331a to 331f in the first embodiment.
Each of 32a to 432e has the same configuration as each of the FPC insertion holes 332a to 332c in the first embodiment.

As shown in FIG. 27, the first surface 321 of the substrate 320 is provided with an integrated circuit 241 that constitutes the diagnostic circuit 240 . The integrated circuit 241 is provided on the first surface 321 side of the substrate 320, between the fixing portion 347 and the fixing portion 349, and on the fourth side 326 side of the FPC insertion holes 432a to 432e. Then, the integrated circuit 241 that constitutes the diagnostic circuit 240 determines whether ink can be discharged normally from the nozzles 651 based on the diagnostic signals DIG-A to DIG-D and DIG-F to DIG-I. . Although one integrated circuit 241 is shown as the diagnostic circuit 240 in FIG. 27, the diagnostic circuit 240 may be composed of two or more integrated circuit devices. Specifically, the substrate 320 includes an integrated circuit 241 that determines whether ink can be discharged normally from the nozzles 651 based on the diagnostic signals DIG-A to DIG-D, and diagnostic signals DIG-F to DIG-D. An integrated circuit 241 may be provided that determines whether ink can be discharged normally from the nozzles 651 based on the DIG-I.

Further, as shown in FIGS. 26 and 27, the substrate 320 is provided with connectors 350, 360, 370, and 380. FIG. The connector 350 is provided along the first side 323 on the first surface 321 side of the substrate 320 . Also, the connector 360 is provided along the first side 323 on the second surface 322 side of the substrate 320 . Here, the connectors 350 and 360 in the second embodiment differ from the first embodiment only in that the number of terminals included is 20, and the rest of the configuration is the same as in the first embodiment. . Therefore, detailed description of the connectors 350 and 360 in the second embodiment is omitted. In addition, the 20 terminals 353 arranged side by side in the connector 350 in the second embodiment are sequentially arranged from the third side 325 side toward the fourth side 326 side in the direction along the first side 323. Terminals 353- 1, 353-2, . , 363-20 in order toward the four sides 326 side.

The connector 370 is provided along the second side 324 on the first surface 321 side of the substrate 320 . Also, the connector 380 is provided along the second side 324 on the second surface 322 side of the substrate 320 . The configuration of connectors 370 and 380 will be described with reference to FIG. FIG. 28 is a diagram showing the configuration of connectors 370 and 380. As shown in FIG.

Connector 370 has a housing 371 , a cable attachment portion 372 formed in housing 371 , and a plurality of terminals 373 . A plurality of terminals 373 are arranged side by side along the second side 324 . Specifically, twenty terminals 373 are arranged side by side along the second side 324 . 373-1, 373-2, . 20. The cable attachment portion 372 is positioned on the substrate 320 of the plurality of terminals 373 in the Z direction. A propagation path such as a flexible flat cable is attached to the cable attachment portion 372 .

Connector 380 has a housing 381 , a cable attachment portion 382 formed in housing 381 , and a plurality of terminals 383 . A plurality of terminals 383 are arranged side by side along the second side 324 . Specifically, twenty terminals 383 are arranged side by side along the second side 324 . 383-1, 383-2, . 20. The cable attachment portion 382 is located on the substrate 320 of the plurality of terminals 383 in the Z direction. A propagation path such as a flexible flat cable is attached to the cable attachment portion 382 .

FIG. 29 is a cross-sectional view of the print head 21 in the second embodiment when viewed from the Y direction. As shown in FIG. 29, a plurality of nozzle rows L1 to L10 are arranged side by side in the X direction. Specifically, the plurality of nozzle rows L1 to L10 are arranged from the first side 323 on which the connector 350 of the substrate 320 is provided toward the second side 324 on which the connector 370 is provided. , L3, L4, L5, L6, L7, L8, L9, and L10.

Therefore, the shortest distance between the plurality of piezoelectric elements 60 included in the nozzle row L1 corresponding to the drive signal selection circuit 200-1 and the connector 350 is the distance between the plurality of piezoelectric elements 60 included in the nozzle row L2 corresponding to the drive signal selection circuit 200-2. Shorter than the shortest distance between the piezoelectric element 60 and the connector 350 . Furthermore, in this case, between the plurality of piezoelectric elements 60 included in the nozzle row L1 corresponding to the drive signal selection circuit 200-1 and the connector 350, there are other nozzle rows L2 to L10 and nozzle rows L2 to L10. The piezoelectric element 60 included in each is not positioned. In other words, the nozzle row L1 is positioned closest to the connector 350 among the nozzle rows L1 to L10 formed on the ink ejection surface 311. In FIG.

That is, the print head 21 has a plurality of flexible wiring boards 335 electrically connected to the substrate 320, and the shortest distance between the flexible wiring boards 335 corresponding to the nozzle row L1 and the connector 350 is the nozzle row L2. It is shorter than the shortest distance between corresponding flexible wiring board 335 and connector 350 . Furthermore, the flexible wiring board 335 corresponding to the nozzle row L1 is provided closest to the connector 350 among the plurality of flexible wiring boards 335 of the print head 21 . Here, the flexible wiring board 335 corresponding to the nozzle row L1 is an example of the first wiring board in the second embodiment, and the flexible wiring board 335 corresponding to the nozzle row L2 is an example of the second wiring board in the second embodiment. , and the plurality of flexible wiring boards 335 including the flexible wiring board 335 corresponding to the nozzle row L1 and the flexible wiring board 335 corresponding to the nozzle row L2 are examples of the plurality of wiring substrates in the second embodiment. Also, the connector 350 is an example of the connector in the second embodiment.

Similarly, the shortest distance between the plurality of piezoelectric elements 60 included in the nozzle row L10 corresponding to the drive signal selection circuit 200-10 and the connector 370 is the plurality of piezoelectric elements 60 included in the nozzle row L9 corresponding to the drive signal selection circuit 200-9. shorter than the shortest distance between the piezoelectric element 60 and the connector 370. Furthermore, in this case, between the plurality of piezoelectric elements 60 included in the nozzle row L10 corresponding to the drive signal selection circuit 200-10 and the connector 370, there are other nozzle rows L1 to L9 and nozzle rows L1 to L9. The piezoelectric element 60 included in each is not positioned. In other words, the nozzle row L10 is positioned closest to the connector 360 among the nozzle rows L1 to L10 formed on the ink ejection surface 311. In FIG.

That is, the print head 21 has a plurality of flexible wiring boards 335 electrically connected to the substrate 320, and the shortest distance between the flexible wiring boards 335 corresponding to the nozzle row L10 and the connector 360 is the nozzle row L9. It is shorter than the shortest distance between corresponding flexible wiring board 335 and connector 360 . Furthermore, the flexible wiring board 335 corresponding to the nozzle row L10 is provided closest to the connector 360 among the plurality of flexible wiring boards 335 of the print head 21 . Here, the flexible wiring board 335 corresponding to the nozzle row L10 is another example of the first wiring board in the second embodiment, and the flexible wiring board 335 corresponding to the nozzle row L9 is the second wiring board in the second embodiment. Another example of Also, the connector 370 is another example of the connector in the second embodiment.

Next, details of the signals input to the connectors 350, 360, 370 and 380 will be described with reference to FIGS. 30 to 33. FIG.

FIG. 30 is a diagram for explaining details of signals input to the connector 350 in the second embodiment. As shown in FIG. 30, the connector 350 has terminals to which drive signals COM1 to COM5 are input, terminals to which reference voltage signals CGND1 to CGND5 are input, temperature signal TH, latch signal LAT1, and clock signal. A terminal to which SCK1, change signal CH1, and setting signal TD1 are input, a terminal to which diagnostic signals DIG-A to DIG-D are input, and a plurality of terminals to which a plurality of ground signals GND are input. including.

Specifically, each of the drive signals COM1 to COM5 is input to each of terminals 353-9, 353-7, 353-5, 353-3, and 353-2. Also, the reference voltage signals CGND1 to CGND5 are input to terminals 353-10, 353-8, 353-6, 353-4 and 353-2, respectively.

Diagnostic signal DIG-A and latch signal LAT1 are both input to terminal 353-17. That is, the terminal 353-17 serves as both a terminal to which the diagnostic signal DIG-A is input and a terminal to which the latch signal LAT1 is input. A terminal 353-17 serving as both a terminal to which the diagnostic signal DIG-A is input and a terminal to which the latch signal LAT1 is input is an example of a second terminal in the second embodiment.

Both the diagnostic signal DIG-B and the clock signal SCK1 are input to the terminal 353-15. That is, the terminal 353-15 serves as both a terminal to which the diagnostic signal DIG-B is input and a terminal to which the clock signal SCK1 is input. The terminal 353-15 serving as both the terminal to which the diagnostic signal DIG-B is input and the terminal to which the clock signal SCK1 is input is an example of the fourth terminal in the second embodiment.

Both the diagnostic signal DIG-C and the change signal CH1 are input to the terminal 353-13. That is, the terminal 353-13 serves both as a terminal to which the diagnostic signal DIG-C is input and a terminal to which the change signal CH1 is input. A terminal 353-13 serving as both a terminal to which the diagnostic signal DIG-C is input and a terminal to which the change signal CH1 is input is an example of a third terminal in the second embodiment.

Both the diagnostic signal DIG-D and the setting signal TD1 are input to the terminal 353-11. That is, the terminal 353-11 serves both as a terminal to which the diagnostic signal DIG-D is input and a terminal to which the setting signal TD1 is input. The terminal 353-11 serving as both the terminal to which the diagnostic signal DIG-D is input and the terminal to which the setting signal TD1 is input is an example of the first terminal in the second embodiment.

As described above, the connector 350 has a terminal 353-11 to which the diagnostic signal DIG-D is input, a terminal 353-17 to which the diagnostic signal DIG-A is input, and a terminal 353-13 to which the diagnostic signal DIG-C is input. , a terminal 353-15 to which the diagnostic signal DIG-B is input, and a terminal 353-9 to which the driving signal COM1 is input.

Temperature signal TH is input to connector 350 at terminal 353-19. Also, the ground signal GND is input to each of terminals 353-12, 353-14, 353-16, 353-18, and 353-20.

FIG. 31 is a diagram for explaining details of signals input to the connector 360 in the second embodiment. As shown in FIG. 31, the connector 360 has terminals to which drive signals COM1 to COM5 are input, terminals to which reference voltage signals CGND1 to CGND5 are input, and setting signals TD2 to TD5. , a terminal to which voltage VDD1 is input, and a plurality of terminals to which a plurality of ground signals GND are input.

Specifically, each of the drive signals COM1 to COM5 is input to each of terminals 363-10, 363-8, 363-6, 363-4, and 363-2. Also, the reference voltage signals CGND1 to CGND5 are input to terminals 363-9, 363-7, 363-5, 363-3 and 363-1, respectively.

The setting signals TD2 to TD5 are input to terminals 363-18, 363-16, 363-14 and 363-12, respectively. Voltage VDD1 is also input to terminal 363-20. Also, the ground signal GND is input to each of terminals 353-11, 353-13, 353-15, 353-17, and 353-19.

FIG. 32 is a diagram for explaining the details of the signal input to connector 370. As shown in FIG. As shown in FIG. 32, the connector 370 has terminals to which drive signals COM6 to COM10 are input, terminals to which reference voltage signals CGND6 to CGND10 are input, an abnormality signal XHOT, a latch signal LAT2, and a clock signal. A terminal to which SCK2, a change signal CH2, and a setting signal TD10 are input, a terminal to which diagnostic signals DIG-E to DIG-I are input, and a plurality of terminals to which a plurality of ground signals GND are input. including.

Specifically, each of the drive signals COM6 to COM10 is input to each of terminals 373-2, 373-4, 373-6, 373-8 and 373-10. Also, the reference voltage signals CGND6 to CGND10 are input to terminals 373-1, 373-3, 373-5, 373-7 and 373-9, respectively.

Both the diagnostic signal DIG-E and the abnormal signal XHOT are input to the terminal 373-12.

Diagnostic signal DIG-F and latch signal LAT2 are both input to terminal 373-14. That is, the terminal 373-14 serves both as a terminal to which the diagnostic signal DIG-F is input and a terminal to which the latch signal LAT2 is input. The terminal 373-14 serving as both the terminal to which the diagnostic signal DIG-F is input and the terminal to which the latch signal LAT2 is input is another example of the second terminal in the second embodiment.

Diagnostic signal DIG-G and clock signal SCK2 are both input to terminal 373-16. That is, the terminal 373-16 serves as both a terminal to which the diagnostic signal DIG-G is input and a terminal to which the clock signal SCK2 is input. The terminal 373-16 serving as both the terminal to which the diagnostic signal DIG-G is input and the terminal to which the clock signal SCK2 is input is another example of the fourth terminal in the second embodiment.

Diagnosis signal DIG-H and change signal CH2 are both input to terminal 373-18. That is, the terminal 373-8 serves both as a terminal to which the diagnostic signal DIG-H is input and a terminal to which the change signal CH2 is input. The terminal 373-18 serving both as a terminal to which the diagnostic signal DIG-H is input and a terminal to which the change signal CH2 is input is another example of the third terminal in the second embodiment.

Both the diagnostic signal DIG-I and the setting signal TD10 are input to the terminal 373-20. That is, the terminal 373-20 serves both as a terminal to which the diagnostic signal DIG-I is input and a terminal to which the setting signal TD10 is input. The terminal 373-20 serving as both the terminal to which the diagnostic signal DIG-I is input and the terminal to which the setting signal TD10 is input is another example of the first terminal in the second embodiment.

As described above, the connector 370 has a terminal 373-20 to which the diagnostic signal DIG-I is input, a terminal 373-14 to which the diagnostic signal DIG-F is input, and a terminal 373-18 to which the diagnostic signal DIG-H is input. , a terminal 373-16 to which the diagnostic signal DIG-G is input, and a terminal 373-10 to which the drive signal COM10 is input.

A ground signal GND is input to each of terminals 373-11, 373-13, 373-15, 373-17 and 373-19.

FIG. 33 is a diagram for explaining the details of the signal input to connector 380. As shown in FIG. As shown in FIG. 33, connector 380 has terminals to which drive signals COM6 to COM10 are input, terminals to which reference voltage signals CGND6 to CGND10 are input, and setting signals TD6 to TD9. , terminals to which voltages VHV and VDD2 are respectively input, and a plurality of terminals to which a plurality of ground signals GND are input.

Specifically, each of drive signals COM6 to COM10 is input to each of terminals 383-1, 373-3, 373-5, 373-7, and 373-9. Also, the reference voltage signals CGND6 to CGND10 are input to terminals 383-2, 383-4, 383-6, 383-8 and 383-10, respectively.

The setting signals TD6 to TD9 are input to terminals 383-13, 383-15, 383-17 and 383-19, respectively. Also, the voltage VHV is input to the terminal 383-11. Also, voltage VDD2 is input to terminal 383-16.

A ground signal GND is input to each of terminals 383-12, 383-14, 383-18 and 383-20.

Here, referring to FIG. 34, diagnostic signals DIG-A to DIG-D input from connector 350 and diagnostic signals DIG-E to DIG-I input from connector 370 are detected on first surface 321 of substrate 320. An example of a propagating wiring will be described. FIG. 34 is a diagram showing an example of wiring formed on the first surface 321 of the substrate 320 in the second embodiment. Note that in FIG. 34, illustration of a part of the wiring formed on the substrate 320 is omitted. Also, in FIG. 34, electrode groups 430a to 430j formed on the second surface 322 of the substrate 320 are indicated by broken lines.

As shown in FIG. 34, the substrate 320 has wirings 354-a to 354-d, 354-f to 354-n, and wirings 374-a to 374-o.

The terminal 353-17 is electrically connected to the wiring 354-a. The diagnostic signal DIG-A and the latch signal LAT1 input from the terminal 353-17 are input to the integrated circuit 241 after propagating through the wiring 354-a. That is, the wiring 354-a electrically connects the terminal 353-17 and the integrated circuit 241. FIG. The wiring 354-a through which the diagnostic signal DIG-A and the latch signal LAT1 propagate is an example of the second wiring of the second embodiment.

The terminal 353-15 is electrically connected to the wiring 354-b. The diagnostic signal DIG-B and the clock signal SCK1 input from the terminal 353-15 are input to the integrated circuit 241 after propagating through the wiring 354-b. That is, the wiring 354-b electrically connects the terminal 353-15 and the integrated circuit 241. FIG. The wiring 354-b through which the diagnostic signal DIG-B and the clock signal SCK1 propagate is an example of the fourth wiring of the second embodiment.

The terminal 353-13 is electrically connected to the wiring 354-c. The diagnostic signal DIG-C and the change signal CH1 input from the terminal 353-13 are input to the integrated circuit 241 after propagating through the wiring 354-c. That is, the wiring 354-c electrically connects the terminal 353-13 and the integrated circuit 241. FIG. The wiring 354-c through which the diagnosis signal DIG-C and the change signal CH1 are propagated is an example of the third wiring of the second embodiment.

The terminal 353-11 is electrically connected to the wiring 354-d. The diagnostic signal DIG-D and the setting signal TD1 input from the terminal 353-11 are input to the integrated circuit 241 after propagating through the wiring 354-d. That is, the wiring 354-d electrically connects the terminal 353-17 and the integrated circuit 241. FIG. The wiring 354-d through which the diagnosis signal DIG-D and the setting signal TD1 propagate is an example of the first wiring of the second embodiment.

As described above, when the integrated circuit 241 determines that ink can be ejected normally from the print head 21 based on the input diagnostic signals DIG-A to DIG-D, the integrated circuit 241 outputs the input latch signal LAT1, clock The signal SCK1 and the change signal CH1 are output to the driving signal selection circuit 200 as the latch signal cLAT1, the clock signal cSCK1 and the change signal cCH1. Specifically, the change signal cCH1, the clock signal cSCK1, and the latch signal cLAT1 that are output from terminals (not shown) of the integrated circuit 241 propagate through the wirings 354-f to 354-h and are input to the drive signal selection circuit 200. be. That is, the wirings 354-f to 354-h electrically connect the integrated circuit 241 and the flexible wiring board 335. FIG. At least one of the wirings 354-f to 354-h through which the change signal cCH, the clock signal cSCK, and the latch signal cLAT propagate is an example of the sixth wiring in the second embodiment.

Specifically, the integrated circuit 241 forming the diagnostic circuit 240 is electrically connected to the wiring 354-f. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 354-f is electrically connected to the wiring 354-c through the integrated circuit 241. FIG. As a result, the change signal cCH1 based on the change signal CH1 is input to the wiring 354-f. The change signal cCH1 is input to one of a plurality of electrodes included in the electrode group 430a provided on the second surface 322 of the substrate 320 via the wiring 354-f and vias (not shown). The change signal cCH1 is input to the drive signal selection circuit 200-1 via the flexible wiring board 335 connected to the electrode group 430a. That is, the wiring 354-f electrically connects the integrated circuit 241 and the flexible wiring board 335. FIG.

In addition, the integrated circuit 241 is electrically connected to the wiring 354-g. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 354-g is electrically connected to the wiring 354-b through the integrated circuit 241. FIG. As a result, the wiring 354-g receives the clock signal cSCK1 based on the clock signal SCK1. The clock signal cSCK1 is input to one of a plurality of electrodes included in the electrode group 430a provided on the second surface 322 of the substrate 320 via the wiring 354-g and vias (not shown). The clock signal cSCK1 is input to the drive signal selection circuit 200-1 through the flexible wiring board 335 connected to the electrode group 430a. That is, the wiring 354 - g electrically connects the integrated circuit 241 and the flexible wiring board 335 .

In addition, the integrated circuit 241 is electrically connected to the wiring 354-h. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 354-h is electrically connected to the wiring 354-a via the integrated circuit 241. FIG. As a result, the latch signal cLAT1 based on the latch signal LAT1 is input to the wiring 354-h. The latch signal cLAT1 is input to one of the electrodes included in the electrode group 430a provided on the second surface 322 of the substrate 320 via the wiring 354-h and vias (not shown). The latch signal cLAT1 is input to the drive signal selection circuit 200-1 through the flexible wiring board 335 connected to the electrode group 430a. That is, the wiring 354-h electrically connects the integrated circuit 241 and the flexible wiring board 335. FIG.

Furthermore, as shown in FIG. 34, the terminal 353-11 is also electrically connected to the wiring 354-i. The setting signal TD1 input from the terminal 353-11 propagates through the wiring 354-i, and then passes through vias (not shown) and the like to a plurality of electrodes included in the electrode group 430a provided on the second surface 322 of the substrate 320. It is input to one of the electrodes and supplied to the drive signal selection circuit 200 via the flexible wiring board 335 . That is, the wiring 354-i electrically connects the terminal 353-11 and the flexible wiring board 335. FIG. The wiring 354-i through which the setting signal TD1 propagates is an example of the fifth wiring.

A terminal 353-9 to which the driving signal COM1 is input is electrically connected to the wiring 354-j. After being propagated through the wiring 354-j, the drive signal COM1 is input to one of the electrodes included in the electrode group 430a provided on the second surface 322 of the substrate 320 via vias (not shown). be done. The drive signal COM1 is input to the drive signal selection circuit 200-1 through the flexible wiring board 335 connected to the electrode group 430a. That is, the wiring 354-j electrically connects the terminal 353-9 and the driving signal selection circuit 200-1.

Similarly, terminals 353-7, 353-5, 353-3, and 353-1 to which drive signals COM2 to COM5 are input are electrically connected to wirings 354-k to 354-n, respectively. . Then, the driving signals COM2 to COM5 are propagated through the wirings 354-k to 354-m, respectively, and then through vias (not shown) to the electrode groups 430b to 430e provided on the second surface 322 of the substrate 320. Input to any of the included electrodes.

The terminal 373-20 is electrically connected to the wiring 374-a. The diagnostic signal DIG-I and the setting signal TD10 input from the terminal 373-20 are input to the integrated circuit 241 after propagating through the wiring 374-a. That is, the wiring 374-d electrically connects the terminal 373-20 and the integrated circuit 241. FIG. The wiring 374-a through which the diagnostic signal DIG-I and the setting signal TD10 propagate is another example of the first wiring of the second embodiment.

The terminal 373-18 is electrically connected to the wiring 374-b. The diagnostic signal DIG-H and the change signal CH2 input from the terminal 373-18 are input to the integrated circuit 241 after propagating through the wiring 374-b. That is, the wiring 374-b electrically connects the terminal 373-18 and the integrated circuit 241. FIG. The wiring 374-b through which the diagnosis signal DIG-H and the change signal CH2 are propagated is another example of the third wiring of the second embodiment.

The terminal 373-16 is electrically connected to the wiring 374-c. The diagnostic signal DIG-G and the clock signal SCK2 input from the terminal 373-16 are input to the integrated circuit 241 after propagating through the wiring 374-c. That is, the wiring 374-c electrically connects the terminal 373-16 and the integrated circuit 241. FIG. The wiring 374-c through which the diagnostic signal DIG-B and the clock signal SCK2 are propagated is another example of the fourth wiring of the second embodiment.

The terminal 373-14 is electrically connected to the wiring 374-d. The diagnostic signal DIG-F and the latch signal LAT2 input from the terminal 373-14 are input to the integrated circuit 241 after propagating through the wiring 374-d. That is, the wiring 374-d electrically connects the terminal 373-14 and the integrated circuit 241. FIG. The wiring 374-d through which the diagnostic signal DIG-F and the latch signal LAT2 propagate is another example of the second wiring of the second embodiment.

When the integrated circuit 241 determines that ink can be ejected normally from the print head 21 based on the input diagnostic signals DIG-F to DIG-I, the integrated circuit 241 outputs the input latch signal LAT2, clock signal SCK2, and The change signal CH2 is output to the drive signal selection circuit 200 via the flexible wiring board 335 as the latch signal cLAT2, the clock signal cSCK2 and the change signal cCH2. Specifically, the latch signal cLAT2, the clock signal cSCK2, and the change signal cCH2 output from terminals (not shown) of the integrated circuit 241 propagate through the wirings 374-f to 374-h and pass through the flexible wiring board 335. It is input to the drive signal selection circuit 200 . That is, the wirings 374-f to 374-h electrically connect the integrated circuit 241 and the flexible wiring board 335. FIG. At least one of the wirings 374-f to 374-h is another example of the sixth wiring in the second embodiment.

Specifically, the integrated circuit 241 forming the diagnostic circuit 240 is electrically connected to the wiring 374-f. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 374-f is electrically connected to the wiring 374-d via the integrated circuit 241. FIG. As a result, the wiring 374-f receives the latch signal cLAT2 based on the latch signal LAT2. The latch signal cLAT2 is input to one of the electrodes included in the electrode group 430j provided on the second surface 322 of the substrate 320 via the wiring 374-f and vias (not shown). The latch signal cLAT2 is input to the drive signal selection circuit 200-10 through the flexible wiring board 335 connected to the electrode group 430j. That is, the wiring 374-f electrically connects the integrated circuit 241 and the drive signal selection circuit 200-10.

In addition, the integrated circuit 241 is electrically connected to the wiring 374-g. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 374-g is electrically connected through the integrated circuit 241 to the wiring 374-c. As a result, the wiring 374-g receives the clock signal cSCK2 based on the clock signal SCK2. The clock signal cSCK2 is input to one of a plurality of electrodes included in the electrode group 430j provided on the second surface 322 of the substrate 320 via the wiring 374-g and vias (not shown). The clock signal cSCK2 is input to the drive signal selection circuit 200-10 through the flexible wiring board 335 connected to the electrode group 430j. That is, the wiring 374-g electrically connects the integrated circuit 241 and the drive signal selection circuit 200-10.

In addition, the integrated circuit 241 is electrically connected to the wiring 374-h. When the diagnosis circuit 240 diagnoses that the print head 21 can eject ink normally, the wiring 374-h is electrically connected to the wiring 374-b through the integrated circuit 241. FIG. As a result, the change signal cCH2 based on the change signal CH2 is input to the wiring 374-h. The change signal cCH2 is input to one of a plurality of electrodes included in the electrode group 430j provided on the second surface 322 of the substrate 320 via the wiring 374-h and vias (not shown). The change signal cCH2 is input to the drive signal selection circuit 200-10 via the flexible wiring board 335 connected to the electrode group 430j. That is, the wiring 374-h electrically connects the integrated circuit 241 and the driving signal selection circuit 200-10.

Further, as shown in FIG. 34, terminal 373-14 is also electrically connected to wiring 374-i. The setting signal TD10 input from the terminal 373-14 is propagated through the wiring 374-i, and then passes through vias (not shown) or the like to a plurality of electrodes included in the electrode group 430j provided on the second surface 322 of the substrate 320. input to one of the electrodes. The wiring 374-i through which the setting signal TD10 propagates is another example of the fifth wiring of the second embodiment. The print data signal SI10 is input to the drive signal selection circuit 200-10 through the flexible wiring board 335 connected to the electrode group 430j. That is, the wiring 374-i electrically connects the terminal 373-14 and the drive signal selection circuit 200-1.

A terminal 373-10 to which the driving signal COM10 is input is electrically connected to the wiring 374-j. After being propagated through the wiring 374-j, the drive signal COM10 is transferred to one of the plurality of electrodes included in the electrode group 430j provided on the second surface 322 of the substrate 320 via vias (not shown) or the like. is entered. The drive signal COM10 is input to the drive signal selection circuit 200-10 through the flexible wiring board 335 connected to the electrode group 430j. That is, the wiring 374-j electrically connects the terminal 373-10 and the drive signal selection circuit 200-10.

Similarly, terminals 373-8, 373-6, 373-4, and 373-2 to which drive signals COM9 to COM6 are input are electrically connected to wirings 374-k to 374-n, respectively. . Then, after each of the drive signals COM9 to COM6 is propagated through the wirings 374-k to 374-m, the electrodes 430i to 430f provided on the second surface 322 of the substrate 320 through vias (not shown). Input to any of the included electrodes.

As described above, even when two sets of diagnostic signals DIG-A to DIG-D and diagnostic signals DIG-F to DIG-I are input from each of the two connectors 350 and 370, As in the first embodiment, it is possible to achieve both the normal execution of the self-diagnostic function and the execution of the printing process without deteriorating the ink ejection accuracy.

3 Modification In the liquid ejection device 1 and the print head 21 according to the first embodiment and the second embodiment described above, the piezoelectric element 60 included in the ejection section 600 is displaced to eject ink from the nozzle 651. Any type can be used. Therefore, the piezoelectric element included in the discharge section 600 is not limited to the configuration of being displaced by bending vibration as shown in the first and second embodiments, and may be configured to be displaced by longitudinal vibration.

35A and 35B are diagrams for explaining the configuration of the piezoelectric element 70 and the liquid ejection operation in the modification. In addition, in FIG. 35, the same code|symbol is attached|subjected about the structure similar to 1st Embodiment and 2nd Embodiment.

The piezoelectric element 70 in the modified example is a laminated piezoelectric vibrator in which a piezoelectric body 701 is sandwiched between electrodes 711 and 712 and laminated, and cut into elongated comb-teeth shapes. Such a piezoelectric element 70 is configured as a longitudinally vibrating piezoelectric vibrator that can expand and contract in the longitudinal direction of the vibrator. The piezoelectric element 70 has a so-called cantilever state in which the fixed end portion is joined to the fixed portion 727 and the free end portion protrudes outside the tip edge of the fixed portion 727 . Also, the tip surface of the free end portion of the piezoelectric element 70 is joined to an island portion 749 formed on one surface of the diaphragm 721 . A cavity 731 in which ink supplied from the ink supply port 761 is stored is formed on the other surface side of the vibration plate 721 .

The electrode 711 of the piezoelectric element 70 is an electrode that is continuously formed on the tip surface of the piezoelectric element 70 and the wiring connection surface that is one side surface of the piezoelectric element 70 in the lamination direction and to which the flexible wiring board 335 is connected. It is electrically connected to an individual internal electrode (not shown) formed inside the piezoelectric element 70 . Further, the electrode 712 is an electrode that is continuously formed on the base end surface portion opposite to the tip end surface portion of the piezoelectric element 70 and the other side surface of the piezoelectric element 70 in the stacking direction and on the fixing plate mounting surface. , and a common internal electrode (not shown) formed inside the piezoelectric vibrator 15 .

A drive signal VOUT is supplied to the electrode 711 via the flexible wiring board 335 , and a reference voltage signal CGND is supplied to the electrode 712 via the flexible wiring board 335 . At this time, the piezoelectric body 701 is displaced according to the potential difference between the electrodes 711 and 712 and between the individual internal electrodes and the common internal electrode. As a result, the piezoelectric element 70 is driven to expand and contract. In other words, the piezoelectric element 70 longitudinally vibrates due to the potential difference between the drive signal VOUT and the reference voltage signal CGND. As the piezoelectric element 70 is driven to expand and contract, the vibration plate 721 is displaced via the island portion 749 . As a result, the internal volume of cavity 731 changes. Ink is ejected from the nozzle 751 as the internal volume of the cavity 731 changes.

Even the print head 21 having the piezoelectric element 70 that is displaced along with the longitudinal vibration configured as described above is similar to the liquid ejection device 1 and the print head 21 shown in the first and second embodiments. A working effect is obtained.

Although the embodiments and modifications have been described above, the present invention is not limited to these embodiments, and can be implemented in various ways without departing from the scope of the invention. For example, it is also possible to combine the above embodiments as appropriate.

The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same function, method, and result, or configurations that have the same purpose and effect). Moreover, the present invention includes configurations in which non-essential portions of the configurations described in the embodiments are replaced. In addition, the present invention includes a configuration that achieves the same effects or achieves the same purpose as the configurations described in the embodiments. In addition, the present invention includes configurations obtained by adding known techniques to the configurations described in the embodiments.

DESCRIPTION OF SYMBOLS 1... Liquid ejection apparatus 2... Liquid container 10... Control mechanism 15... Piezoelectric vibrator 20... Carriage 21... Print head 30... Moving mechanism 31... Carriage motor 32... Endless belt 40... Conveying mechanism , 41... Conveying motor, 42... Conveying roller, 50... Drive signal output circuit, 50a... Drive circuit, 60, 70... Piezoelectric element, 90... Linear encoder, 100... Control circuit, 110... Power supply circuit, 200... Drive signal selection Circuit 201 Integrated circuit 210 Temperature detection circuit 222a First shift register 222b Second shift register 224a First latch circuit 224b Second latch circuit 226 Decoder 230 Selection circuit 232... Inverter 234... Transfer gate 240... Diagnostic circuit 241... Integrated circuit 250... Abnormal temperature detection circuit 251... Comparator 252... Reference voltage generation circuit 253... Transistor 254... Diode 255, 256... Resistor 260 Control logic circuit 261 SP shift register group 262 Selection control signal generation group 270 Selection control circuit 310 Head 311 Ink discharge surface 320 Substrate 321 First surface 322... Second surface 323... First side 324... Second side 325... Third side 326... Fourth side 330... Electrode group 331... Ink supply path insertion hole 332... FPC insertion hole 335 Flexible wiring board 337 Electrode wiring 341, 342 Wiring 346, 347, 348, 349 Fixing part 350 Connector 351 Housing 352 Cable mounting part 353 Terminal 354 Wiring 360 ...Connector 361...Housing 362...Cable attachment part 363...Terminal 370...Connector 371...Housing 372...Cable attachment part 373...Terminal 374...Wiring 380...Connector 38
REFERENCE SIGNS LIST 1 housing 382 cable mounting portion 383 terminal 430 electrode group 431 ink supply path insertion hole 432 FPC insertion hole 600 ejection portion 601 piezoelectric body 611, 612 electrode 621 Vibration plate 631 Cavity 632 Nozzle plate 641 Reservoir 651 Nozzle 661 Ink supply port 701 Piezoelectric body 711, 712 Electrode 721 Diaphragm 727 Fixed part 731 ... cavity, 749 ... island portion, 751 ... nozzle, 761 ... ink supply port, P ... medium,

Claims (17)

a print head that ejects liquid;
a control circuit for controlling the operation of the printhead;
with
The print head is
a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
has
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
the sixth wiring electrically connects the first integrated circuit and the first wiring board;
the frequency of the signal propagating on the first wiring is higher than the frequency of the signal propagating on the second wiring ;
A liquid ejection device characterized by: a print head that ejects liquid;
a control circuit for controlling the operation of the printhead;
with
The print head is
a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
has
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
the sixth wiring electrically connects the first integrated circuit and the first wiring board;
the frequency of the signal propagating on the first wiring is higher than the frequency of the signal propagating on the third wiring;
A liquid ejection device characterized by: a print head that ejects liquid;
a control circuit for controlling the operation of the printhead;
with
The print head is
a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
has
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
the sixth wiring electrically connects the first integrated circuit and the first wiring board;
The first integrated circuit determines whether normal ejection of liquid is possible based on a first signal, a second signal, a third signal, and a fourth signal;
A liquid ejection device characterized by: A drive signal output circuit that outputs a drive signal is provided,
The drive signal includes a first waveform that causes liquid to be ejected from the print head, a second waveform, and a constant voltage waveform provided between the first waveform and the second waveform,
4. The liquid ejecting apparatus according to claim 3 , characterized in that: The first terminal also serves as a terminal to which the first signal and a fifth signal that defines waveform selection of the drive signal are input.
5. The liquid ejecting apparatus according to claim 4 , characterized in that: The second terminal also serves as a terminal to which the second signal and a sixth signal that defines the ejection timing of the liquid are input.
6. The liquid ejecting apparatus according to claim 4 , wherein: The sixth signal is input to the second terminal during a period in which the drive signal has the constant voltage waveform.
7. The liquid ejecting apparatus according to claim 6 , characterized in that: the third terminal also serves as a terminal to which the third signal and a seventh signal that defines waveform switching timing of the drive signal are input;
8. The liquid ejecting apparatus according to any one of claims 4 to 7 , characterized in that: The seventh signal is input to the third terminal during a period in which the drive signal has the constant voltage waveform.
9. The liquid ejecting apparatus according to claim 8 , characterized in that: the fourth terminal also serves as a terminal to which the fourth signal and an eighth signal that defines the operation timing of the print head are input;
10. The liquid ejecting apparatus according to any one of claims 4 to 9 , characterized in that: the printhead having a second integrated circuit;
The second integrated circuit is provided on the first wiring board,
The first wiring board has a seventh wiring and an eighth wiring,
the seventh wiring electrically connects the fifth wiring and the second integrated circuit;
the eighth wiring electrically connects the sixth wiring and the second integrated circuit;
11. The liquid ejecting apparatus according to any one of claims 1 to 10, characterized by: wherein the connector and the first integrated circuit are provided on the same surface of the circuit board;
12. The liquid ejecting apparatus according to any one of claims 1 to 11, characterized in that: The first wiring board is a flexible wiring board,
13. The liquid ejecting apparatus according to any one of claims 1 to 12 , characterized in that: The print head has a second wiring board electrically connected to the circuit board,
the shortest distance between the first wiring board and the connector is shorter than the shortest distance between the second wiring board and the connector;
14. The liquid ejecting apparatus according to any one of claims 1 to 13 , characterized by: The print head has a plurality of wiring boards including the first wiring board and the second wiring board,
The first wiring board is provided closest to the connector among the plurality of wiring boards,
15. The liquid ejecting apparatus according to claim 14 , characterized in that: a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
with
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
the sixth wiring electrically connects the first integrated circuit and the first wiring board;
the frequency of the signal propagating on the first wiring is higher than the frequency of the signal propagating on the second wiring ;
A printhead characterized by: a connector having a first terminal, a second terminal, a third terminal, and a fourth terminal;
a first integrated circuit;
a circuit board provided with the connector and the first integrated circuit;
a first wiring board electrically connected to the circuit board;
with
The circuit board has a first wiring, a second wiring, a third wiring, a fourth wiring, a fifth wiring, and a sixth wiring,
the first wiring electrically connects the first terminal and the first integrated circuit;
the second wiring electrically connects the second terminal and the first integrated circuit;
the third wiring electrically connects the third terminal and the first integrated circuit;
the fourth wiring electrically connects the fourth terminal and the first integrated circuit;
the fifth wiring electrically connects the first terminal and the first wiring board;
the sixth wiring electrically connects the first integrated circuit and the first wiring board;
the frequency of the signal propagating on the first wiring is higher than the frequency of the signal propagating on the third wiring;
A printhead characterized by:

Images