JP7243295B2 - PRINT HEAD CONTROL CIRCUIT, PRINT HEAD AND LIQUID EJECTION DEVICE - Google Patents

Description

The present invention relates to a printhead control circuit, a printhead and a liquid ejection device.

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 printhead is disclosed.

JP 2017-114020 A

In the liquid ejecting apparatus disclosed in Patent Document 1, if the waveform of the signal input to the print head for executing the self-diagnostic function is distorted, the self-diagnostic function of the print head may not be executed normally. Patent Literature 1 does not disclose a technique for reducing waveform distortion of a signal for executing the self-diagnostic function as described above.

One aspect of the print head control circuit according to the present invention comprises:
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a first terminal;
a second terminal;
a third terminal;
a fourth terminal;
a fifth terminal;
a sixth terminal;
a seventh terminal;
A first diagnostic signal input to the first terminal, a second diagnostic signal input to the second terminal, a third diagnostic signal input to the third terminal, and a fourth diagnostic signal input to the fourth terminal. a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the diagnostic signal;
a printhead control circuit for controlling the operation of a printhead having
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
A fifth diagnostic signal that is input to the fifth terminal and propagates a fifth diagnostic signal indicating the diagnostic result of the diagnostic circuit.
diagnostic signal propagation wiring;
a first voltage signal propagation wiring for propagating a first voltage signal input to the sixth terminal and supplied to the drive signal selection circuit;
a second voltage signal propagation wiring for propagating a second voltage signal input to the seventh terminal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
with
In a case where the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected to the print head, the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are connected to the first voltage signal propagation wiring. electrically connected via the 5 terminal and the 7th terminal,
the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are positioned side by side;
The first diagnostic signal propagation wiring and the second voltage signal propagation wiring are positioned adjacent to each other in the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged.

One aspect of the print head control circuit according to the present invention comprises:
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a first terminal;
a second terminal;
a third terminal;
a fourth terminal;
a fifth terminal;
a sixth terminal;
a seventh terminal;
A first diagnostic signal input to the first terminal, a second diagnostic signal input to the second terminal, a third diagnostic signal input to the third terminal, and a fourth diagnostic signal input to the fourth terminal. a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the diagnostic signal;
A printhead control circuit for controlling the operation of a printhead comprising:
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates a fifth diagnostic signal that is input to the fifth terminal and indicates a diagnostic result of the diagnostic circuit;
a first voltage signal propagation wiring for propagating a first voltage signal input to the sixth terminal and supplied to the drive signal selection circuit;
a second voltage signal propagation wiring for propagating a second voltage signal input to the seventh terminal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
with
In a case where the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected to the print head, the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are connected to the first voltage signal propagation wiring. electrically connected via the 5 terminal and the 7th terminal,
the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are positioned side by side;
In a direction intersecting the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the first diagnostic signal propagation wiring and the second voltage signal propagation wiring are positioned so as to partially overlap each other. .

In one aspect of the printhead control circuit,
The fifth diagnostic signal propagation wiring may also serve as a wiring for propagating a signal indicating the presence or absence of temperature abnormality in the print head.

In one aspect of the printhead control circuit,
comprising a first ground signal propagation wiring that propagates a ground signal;
The first diagnostic signal propagation wiring and the first ground signal propagation wiring may be positioned adjacent to each other in a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged.

In one aspect of the printhead control circuit,
a third voltage signal propagation wiring for propagating a third voltage signal having a voltage value greater than that of the first voltage signal;
In the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the second voltage signal propagation wiring and the third voltage signal propagation wiring may not be positioned adjacent to each other.

In one aspect of the printhead control circuit,
a third voltage signal propagation wiring for propagating a third voltage signal having a voltage value greater than that of the first voltage signal;
In a direction perpendicular to the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the second voltage signal propagation wiring and the third voltage signal propagation wiring do not have to overlap each other. good.

In one aspect of the printhead control circuit,
comprising a second ground signal propagation wiring that propagates a ground signal;
The third voltage signal propagation wiring and the second ground signal propagation wiring may be positioned adjacent to each other in a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged.

In one aspect of the printhead control circuit,
comprising a second ground signal propagation wiring that propagates a ground signal;
In a direction intersecting the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the third voltage signal propagation wiring and the second ground signal propagation wiring partially overlap each other. may

In one aspect of the printhead control circuit,
the print head has a first connector including the first terminal, the second terminal, the third terminal, the fourth terminal, and the fifth terminal; and a substrate;
The first connector and the diagnostic circuit are provided on the same surface of the substrate,
The first diagnostic signal propagation wiring, the second diagnostic signal propagation wiring, the third diagnostic signal propagation wiring, the fourth diagnostic signal propagation wiring, and the fifth diagnostic signal propagation wiring are provided on the same cable,
The cable may be electrically connected to the first connector.

In one aspect of the printhead control circuit,
The first diagnostic signal propagation wiring may also serve as a wiring for propagating a clock signal.

In one aspect of the printhead control circuit,
The second diagnostic signal propagation wiring may also serve as a wiring for propagating a signal that defines the ejection timing of the liquid.

In one aspect of the printhead control circuit,
The third diagnostic signal propagation wiring may also serve as a wiring for propagating a signal that defines waveform switching timing of the drive signal.

In one aspect of the printhead control circuit,
The fourth diagnostic signal propagation wiring may also serve as a wiring for propagating a signal that defines waveform selection of the drive signal.

One aspect of the print head according to the present invention includes:
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
with
the fifth terminal and the seventh terminal are electrically connected,
the first terminal and the second terminal are positioned side by side;
The first terminal and the seventh terminal are positioned adjacent to each other in the direction in which the first terminal and the second terminal are arranged.

One aspect of the print head according to the present invention includes:
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
with
the fifth terminal and the seventh terminal are electrically connected,
the first terminal and the second terminal are positioned side by side;
The first terminal and the seventh terminal are partially overlapped in a direction crossing the direction in which the first terminal and the second terminal are arranged.

In one aspect of the printhead,
Equipped with a temperature abnormality detection circuit that diagnoses the presence or absence of temperature abnormalities,
The fifth terminal may also serve as wiring for propagating a signal indicating the presence or absence of the temperature abnormality.

In one aspect of the printhead,
A first ground terminal to which a ground signal is input,
The first terminal and the first ground terminal may be positioned adjacent to each other in a direction in which the first terminal and the second terminal are arranged.

In one aspect of the printhead,
an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input;
The seventh terminal and the eighth terminal may not be positioned adjacent to each other in the direction in which the first terminal and the second terminal are arranged.

In one aspect of the printhead,
an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input;
In a direction orthogonal to the direction in which the first terminal and the second terminal are arranged, the seventh terminal and the eighth terminal may not overlap each other.

In one aspect of the printhead,
A second ground terminal to which a ground signal is input,
The eighth terminal and the second ground terminal may be positioned adjacent to each other in a direction in which the first terminal and the second terminal are arranged.

In one aspect of the printhead,
A second ground terminal to which a ground signal is input,
The eighth terminal and the second ground terminal may be partially overlapped in a direction crossing the direction in which the first terminal and the second terminal are arranged.

In one aspect of the printhead,
a first connector including the first terminal, the second terminal, the third terminal, the fourth terminal, and the fifth terminal;
a substrate;
with
The first connector and the diagnostic circuit may be provided on the same side of the board.

In one aspect of the printhead,
The first terminal may also serve as a terminal to which a clock signal is input.

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

In one aspect of the printhead,
The third terminal may also serve as a terminal to which a signal specifying waveform switching timing of the drive signal is input.

In one aspect of the printhead,
The fourth terminal may also serve as a terminal to which a signal specifying waveform selection of the drive signal is input.

One aspect of the liquid ejection device according to the present invention includes:
a print head;
a printhead control circuit for controlling the operation of the printhead;
with
The print head is
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
has
The printhead control circuit comprises:
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates the fifth diagnostic signal;
a first voltage signal propagation wiring that propagates the first voltage signal;
a second voltage signal propagation wiring that propagates the second voltage signal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
has
the first diagnostic signal propagation wiring and the first terminal are in electrical contact at a first contact portion;
the second diagnostic signal propagation wiring and the second terminal are in electrical contact at a second contact portion;
the third diagnostic signal propagation wiring and the third terminal are in electrical contact at a third contact portion;
the fourth diagnostic signal propagation wiring and the fourth terminal are in electrical contact at a fourth contact portion;
the fifth diagnostic signal propagation wiring and the fifth terminal are in electrical contact at a fifth contact portion;
the first voltage signal propagation wiring and the sixth terminal are in electrical contact at a sixth contact portion;
the second voltage signal propagation wiring and the seventh terminal are in electrical contact at a seventh contact portion;
the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected via the fifth terminal, the fifth contact portion, the seventh contact portion, and the seventh terminal;
The first contact portion and the second contact portion are positioned side by side,
The first contact portion and the seventh contact portion are positioned adjacent to each other in the direction in which the first contact portion and the second contact portion are arranged.

One aspect of the liquid ejection device according to the present invention includes:
a print head;
a printhead control circuit for controlling the operation of the printhead;
with
The print head is
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
has
The printhead control circuit comprises:
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates the fifth diagnostic signal;
a first voltage signal propagation wiring that propagates the first voltage signal;
a second voltage signal propagation wiring that propagates the second voltage signal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
has
the first diagnostic signal propagation wiring and the first terminal are in electrical contact at a first contact portion;
the second diagnostic signal propagation wiring and the second terminal are in electrical contact at a second contact portion;
the third diagnostic signal propagation wiring and the third terminal are in electrical contact at a third contact portion;
the fourth diagnostic signal propagation wiring and the fourth terminal are in electrical contact at a fourth contact portion;
the fifth diagnostic signal propagation wiring and the fifth terminal are in electrical contact at a fifth contact portion;
the first voltage signal propagation wiring and the sixth terminal are in electrical contact at a sixth contact portion;
the second voltage signal propagation wiring and the seventh terminal are in electrical contact at a seventh contact portion;
the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected via the fifth terminal, the fifth contact portion, the seventh contact portion, and the seventh terminal;
In a direction crossing the direction in which the first contact portion and the second contact portion are arranged, the first contact portion and the seventh contact portion partially overlap each other.

In one aspect of the liquid ejection device,
The print head has a temperature abnormality detection circuit for diagnosing the presence or absence of temperature abnormality,
The fifth diagnostic signal propagation wiring may also serve as a wiring for propagating the signal indicating the presence or absence of the temperature abnormality.

In one aspect of the liquid ejection device,
The print head has a first ground terminal to which a ground signal is input,
The printhead control circuit has a first ground signal propagation line that propagates a ground signal,
the first ground signal propagation wiring and the first ground terminal are in electrical contact at a first ground contact portion;
The first contact portion and the first ground contact portion may be positioned adjacent to each other in a direction in which the first contact portion and the second contact portion are aligned.

In one aspect of the liquid ejection device,
The print head has an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input,
The print head control circuit has a third voltage signal propagation line that propagates the third voltage signal,
the third voltage signal propagation wiring and the eighth terminal are in electrical contact at an eighth contact portion;
In the direction in which the first contact portion and the second contact portion are arranged, the seventh contact portion and the eighth contact portion may not be positioned adjacent to each other.

In one aspect of the liquid ejection device,
The print head has an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input,
The print head control circuit has a third voltage signal propagation line that propagates the third voltage signal,
the third voltage signal propagation wiring and the eighth terminal are in electrical contact at an eighth contact portion;
In a direction orthogonal to the direction in which the first contact portion and the second contact portion are arranged, the seventh contact portion and the eighth contact portion may not overlap each other.

In one aspect of the liquid ejection device,
The print head has a second ground terminal to which a ground signal is input,
The printhead control circuit has a second ground signal propagation line that propagates a ground signal,
the second ground signal propagation wiring and the second ground terminal are in electrical contact at a second ground contact portion;
In a direction in which the first contact portion and the second contact portion are arranged, the eighth contact portion and the second ground contact portion may be positioned adjacent to each other.

In one aspect of the liquid ejection device,
The print head has a second ground terminal to which a ground signal is input,
The printhead control circuit has a second ground signal propagation line that propagates a ground signal,
the second ground signal propagation wiring and the second ground terminal are in electrical contact at a second ground contact portion;
The eighth contact portion and the second ground contact portion may be partially overlapped in a direction crossing the direction in which the first contact portion and the second contact portion are arranged.

In one aspect of the liquid ejection device,
the print head has a first connector having the first terminal, the second terminal, the third terminal, the fourth terminal, and the fifth terminal; and a substrate;
the first connector and the diagnostic circuit are provided on the same side of the substrate;
The first diagnostic signal propagation wiring, the second diagnostic signal propagation wiring, the third diagnostic signal propagation wiring, the fourth diagnostic signal propagation wiring, and the fifth diagnostic signal propagation wiring are provided on the same cable,
The cable may be electrically connected to the first connector.

In one aspect of the liquid ejection device,
The first diagnostic signal propagation wiring may also serve as a wiring for propagating a clock signal.

In one aspect of the liquid ejection device,
The second diagnostic signal propagation wiring may also serve as a wiring for propagating a signal that defines the ejection timing of the liquid.

In one aspect of the liquid ejection device,
The third diagnostic signal propagation wiring may also serve as a wiring for propagating a signal that defines waveform switching timing of the drive signal.

In one aspect of the liquid ejection device,
The fourth diagnostic signal propagation wiring may also serve as a wiring for propagating a signal that defines waveform selection of the drive signal.

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 decoded contents in 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. FIG. 4 is a diagram schematically showing the internal configuration of the liquid ejection device when viewed from the Y direction; It is a figure which shows the structure of a cable. 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. 3 is a plan view when the substrate is viewed from surface 322. FIG. 3 is a plan view when the substrate is viewed from a surface 321; FIG. 3 is a diagram showing the configuration of a connector 350; FIG. FIG. 10 is a diagram showing another configuration of connector 350; FIG. 10 is a diagram for explaining a specific example when the cable is attached to the connector; 4 is a diagram for explaining details of a signal propagated through a cable 19; FIG. FIG. 10 is a diagram schematically showing the internal configuration of the liquid ejection device according to the second embodiment when viewed from the Y direction; FIG. 11 is a perspective view showing the configuration of a print head in a second embodiment; FIG. 10 is a diagram showing the configuration of connectors 350 and 360 in the second embodiment; FIG. FIG. 10 is a diagram for explaining details of signals propagated through a cable 19a in the second embodiment; FIG. 10 is a diagram for explaining details of a signal propagated through a cable 19b in the second embodiment; FIG. FIG. 11 is a block diagram showing the electrical configuration of a liquid ejection device according to a third embodiment; FIG. 12 is a diagram schematically showing the internal configuration of the liquid ejection device according to the third embodiment when viewed from the Y direction; FIG. 11 is a perspective view showing the configuration of a print head 21 according to a third embodiment; FIG. 10 is a diagram showing the configuration of connectors 370 and 380 in the third embodiment; FIG. FIG. 11 is a diagram for explaining details of signals propagated through a cable 19a in the third embodiment; FIG. 11 is a diagram for explaining details of signals propagated through a cable 19b in the third embodiment; FIG. 11 is a diagram for explaining details of signals propagated through a cable 19c in the third embodiment; FIG. 11 is a diagram for explaining details of a signal propagated through a cable 19d in the third embodiment; FIG.

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. Note that the X direction, the Y direction, and the Z direction will be described as directions 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 . Colors of ink stored in the liquid container 2 include 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-like 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 from 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 a print data signal SI1 as a control signal Ctrl-H for controlling the print head 21 based on various signals such as image data input from the host computer and the scanning position of the print head 21. . . . SIn, a change signal CH, a latch signal LAT and a 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, although details will be described later, in the liquid ejection apparatus 1 according to the first embodiment, each of the diagnostic signals DIG-A to DIG-D, the latch signal LAT, the clock signal SCK, the change signal CH, and the print data signal SI1 are propagated to the print head 21 through a common wiring. Specifically, the diagnostic signal DIG-A and the latch signal LAT are propagated through a common wiring, the diagnostic signal DIG-B and the clock signal SCK are propagated through a common wiring, and the diagnostic signal DIG-C and the change signal CH are propagated. are propagated through a common wiring, and the diagnostic signal DIG-D and the print data signal SI1 are propagated through a common wiring. Here, it is an example of a diagnostic signal output circuit in which the control circuit 100 generates the diagnostic signals DIG-A to DIG-D and outputs them to the print head 21. FIG.

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 circuit 50a class-D-amplifies the waveform defined by the drive control signal dA to generate the drive signal COM. The drive signal output circuit 50 outputs the drive signal COM generated by the drive circuit 50a. 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 only needs to be able to amplify the waveform defined by the drive control signal dA, and may be composed of, for example, a class A amplifier circuit, a class B amplifier circuit, or a class AB amplifier circuit.

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 . A drive signal COM including these drive signals COM1 to COMn is 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 an amplification voltage or the like in the drive signal output circuit 50 . Also, the voltages VDD1 and VDD2 are used as power supply voltages, control voltages, etc. for various configurations in the control mechanism 10, respectively. Voltages VHV, VDD1, VDD2 and ground signal GND are also output to 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 signals of a plurality of voltage values other than the voltages VHV, VDD1, VDD2 and the ground signal GND.

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. .

The diagnostic circuit 240 includes a diagnostic signal DIG-A and a latch signal LAT, a diagnostic signal DIG-B and a clock signal SCK, a diagnostic signal DIG-C, a change signal CH, a diagnostic signal DIG-D and a printed Data signal SI1 is input. Then, the diagnostic circuit 240 diagnoses whether or not ink can be discharged 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.

When the diagnosis circuit 240 diagnoses that ink can be discharged normally from the print head 21, the diagnosis 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. Output as signal cCH. Here, after the diagnostic signal DIG-D and the print data signal SI1 are branched in the print head 21, one of the branched signals is input to the diagnostic circuit 240 and the other is input to the drive signal selection circuit 200-1. The print data signal SI1 is a signal with a high transfer rate, and if the waveform of the print data signal SI1 is distorted, the print head 21 may malfunction. By inputting only one of the print data signal SI1 into the diagnostic circuit 240 after branching the print data signal SI1 at the print head 21, the possibility that the waveform of the print data signal SI1 input to the drive signal selection circuit 200-1 is distorted can be eliminated. can be reduced.

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 . Further, the change signal cCH, the latch signal cLAT and the clock signal cSCK may be signals having waveforms obtained by correcting the change signal CH, the latch signal LAT and the clock signal SCK. In this embodiment, the change signal cCH, the latch signal cLAT, and the clock signal cSCK are described as having the same waveforms as the change signal CH, the latch signal LAT, and the clock signal SCK.

The diagnostic circuit 240 also generates a diagnostic signal DIG-E indicating the diagnostic result of the diagnostic circuit 240 and outputs it to the control circuit 100 . Here, the diagnostic circuit 240 in the first embodiment is configured as one or a plurality of integrated circuit (IC: Integrated Circuit) devices, for example.

Voltages VHV and VDD1, drive signals COM1 to COMn, print data signals SI1 to SIn, 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 are used 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 or deselects the drive signals COM1 to COMn based on the print data signals SI1 to SIn, the clock signal cSCK, the latch signal cLAT, and the change signal cCH. By doing so, 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, which are examples of the drive elements included in the corresponding discharge sections 600. FIG. The piezoelectric element 60 is displaced by being supplied with drive signals VOUT1 to VOUTn. Then, an amount of ink corresponding to the displacement is ejected from the ejection section 600 .

Specifically, the drive signal COM1, the print data signal SI1, 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 print data signal SI1, the latch signal cLAT, the change signal cCH, and the clock signal cSCK, thereby generating the drive signal VOUT1. . 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, a drive signal COMi, a print data signal SIi, a latch signal cLAT, a change signal cCH, and a clock signal cSCK are input to the drive signal selection circuit 200-i (where i is one of 1 to n). Then, the drive signal selection circuit 200-i selects the print data signal SIi
, the latch signal cLAT, the change signal cCH, and the clock signal cSCK, the drive signal VOUTi is generated by selecting or deselecting the waveform of the drive signal COMi. 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.

Here, each of drive signal selection circuits 200-1 to 200-n has the same circuit configuration. Therefore, in the following description, the drive signal selection circuits 200-1 to 200-n are referred to as the drive signal selection circuit 200 when there is no need to distinguish between them. In this case, drive signals COM1 to COMn input to drive signal selection circuit 200 are referred to as drive signal COM, print data signals SI1 to SIn are referred to as print data signal SI, and drive signals output from drive signal selection circuit 200 are referred to as print data signals SI. VOUT1 to VOUTn are referred to as drive signal 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.

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 diagnosed to be normal, a high level ( H level) abnormal signal XHOT is generated and output to the control circuit 100 . On the other hand, when temperature abnormality detection circuits 250-1 to 250-n diagnose that the temperature of corresponding drive signal selection circuits 200-1 to 200-n is abnormal, an abnormality signal of low level (L level) is detected. XHOT is generated and output to the control circuit 100 .

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. Here, although details will be described later, the diagnostic signal DIG-E and the abnormal signal XHOT are propagated through common wiring. Details of the temperature abnormality detection circuit 250 will be described later. Also, each of the temperature abnormality detection circuits 250-1 to 250-i is configured as an integrated circuit device, for example. Also, the temperature abnormality detection circuit 250-i and the drive signal selection circuit 200-i may be configured as one integrated circuit device.

Temperature detection circuit 210 includes a temperature detection element such as a thermistor. The temperature detection circuit 210 generates an analog temperature signal TH including temperature information of the print head 21 based on the detection signal detected by the temperature detection element, and outputs the temperature signal TH 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. That is, 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, Adp2, Adp3 included in the drive signal COM. This is a signal that defines waveform switching timing.

Also, the voltages at the start timing and the end timing of each 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.

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 cycle 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 cycle 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. is 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 only 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 P Signals with various combinations of waveforms may be used depending on the material of the .

1.4 Configuration of Drive Signal Selection Circuit Next, the configuration and operation of the drive signal selection circuit 200 will be described. 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 includes a selection control circuit 220 and multiple selection circuits 230 .

The print data signal SI, latch signal cLAT, change signal cCH, and clock signal cSCK are input to the selection control circuit 220 . Also, in the selection control circuit 220, a set of a shift register (S/R) 222, a latch circuit 224, and a decoder 226 is provided corresponding to each of the ejection portions 600. FIG. That is, the drive signal selection circuit 200 includes sets of shift registers 222 , latch circuits 224 , and decoders 226 that are the same in number as the total number m of corresponding ejection sections 600 . Here, the print data signal SI is a signal that defines the waveform selection of the drive signal COM, and the clock signal SCK and the clock signal cSCK are clock signals that define the timing at which the print data signal SI is input.

Specifically, the print data signal SI is a signal synchronized with the clock signal cSCK, and is for each of the m ejection units 600, "large dot", "medium dot", "small dot" and " It is a signal of a total of 2m bits including 2-bit print data [SIH, SIL] for selecting either "non-printing". The print data signal SI is held in the shift register 222 for each 2-bit print data [SIH, SIL] included in the print data signal SI, corresponding to the ejection unit 600 . Specifically, the m-stage shift registers 222 corresponding to the ejection units 600 are cascade-connected to each other, and the serially input print data signal SI is sequentially transferred to subsequent stages in accordance with the clock signal cSCK. In FIG. 5, in order to distinguish the shift registers 222, they are denoted by 1st stage, 2nd stage, .

Each of the m latch circuits 224 latches the 2-bit print data [SIH, SIL] held in each of the m shift registers 222 at the rise of the latch signal cLAT.

Each of the m decoders 226 decodes the 2-bit print data [SIH, SIL] latched by each of the m latch circuits 224 . The decoder 226 outputs the selection signal S every period T1, T2, T3 defined by the latch signal cLAT and the change signal cCH.

FIG. 6 is a diagram showing decoded contents in the decoder 226. As shown in FIG. The decoder 226 outputs the selection signal S according to the latched 2-bit print data [SIH, SIL]. For example, when the 2-bit print data [SIH, SIL] is [1, 0], the decoder 226 outputs the logic level of the selection signal S as H, H, L levels in each of the periods T1, T2, T3. do.

The selection circuit 230 is provided corresponding to each ejection section 600 . That is, the number of selection circuits 230 included in the drive signal selection circuit 200 is the same as the total number m of the corresponding ejection units 600 . 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 turns on the input end and the output end when the selection signal S is at H level, and turns on the input end and the output end when the selection signal S is at L level. between them is non-conducting (off). A drive signal VOUT is output from the output terminal of the transfer gate 234 .

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 is serially input in synchronization with the clock signal cSCK and sequentially transferred in the shift register 222 corresponding to the ejection section 600 . Then, when the input of the clock signal cSCK stops, each shift register 222 holds 2-bit print data [SIH, SIL] corresponding to each ejection unit 600 . Note that the print data signals SI are inputted in the order corresponding to the m-th, .

Then, when the latch signal cLAT rises, each of the latch circuits 224 latches the 2-bit print data [SIH, SIL] held in the shift register 222 all at once. In FIG. 8, LT1, LT2, . show.

The decoder 226 changes the logic level of the selection signal S to the contents shown in FIG. to output.

Specifically, when the print data [SIH, SIL] is [1, 1], the decoder 226 sets the selection signal S to H, H, L levels during periods T1, T2, 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 VOUT corresponding to the "large dot" shown in FIG. 4 is generated.

Further, when the print data [SIH, SIL] is [1, 0], the decoder 226 sets the selection signal S to 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, and does not select the trapezoidal waveform Adp3 in the period T3. As a result, the drive signal VOUT corresponding to the "medium dot" shown in FIG. 4 is generated.

Further, when the print data [SIH, SIL] is [0, 1], the decoder 226 sets the selection signal S to L, H, and L levels during periods T1, T2, and T3. In this case, the selection circuit 230 does not select the trapezoidal waveform Adp1 in the period T1, and selects the trapezoidal waveform Ad in the period T2.
Select p2 and do not select trapezoidal waveform Adp3 in period T3. As a result, the drive signal VOUT corresponding to the "small dot" shown in FIG. 4 is generated.

Further, when the print data [SIH, SIL] is [0, 0], the decoder 226 sets the selection signal S to L, L, and H levels during 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 VOUT corresponding to "non-recording" shown in FIG. 4 is generated.

As described above, the drive signal selection circuit 200 selects the waveform of the drive signal COM based on the print data signal SI, latch signal cLAT, change signal cCH, and clock signal cSCK, and outputs the drive signal VOUT. In other words, the drive signal selection circuit 200 controls supply of the drive signal COM to the piezoelectric element 60 .

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. The number of diodes 254 included in temperature abnormality detection circuit 250 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 XHOT.

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 XHOT.

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 abnormality detection circuit 250 outputs an L level abnormality signal XHOT. That is, in the temperature abnormality detection circuit 250, the transistor 253 is controlled to be turned on or off based on the temperature of the drive signal selection circuit 200, so that the H level abnormality signal XHOT is supplied as the pull-up voltage of the transistor 253. It outputs the voltage VDD2 and outputs the ground signal GND as the L level abnormality signal XHOT.

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 XHOT is output. Therefore, the abnormality signal XHOT 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. Thus, 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 XHOT. Abnormal signal XHOT can be propagated.

1.6 Configuration of Print Head and Print Head Control Circuit Details of the electrical connection between the control mechanism 10 and the print head 21 will now be described. In the following description, it is assumed that the print head 21 of the first embodiment has four drive signal selection circuits 200-1 to 200-4. That is, the print head 21 in the first embodiment has four print data signals SI1 to SI4 corresponding to the four drive signal selection circuits 200-1 to 200-4, respectively, and four drive signals COM1 to COM1 to SI4. COM4 and four reference voltage signals CGND1 to CGND4 are input.

FIG. 10 is a diagram schematically showing the internal configuration of the liquid ejection device 1 when viewed from the Y direction. As shown in FIG. 10, the liquid ejection device 1 has a main substrate 11, a cable 19 and a print head 21.

Various circuits including a drive signal output circuit 50, a control circuit 100, and a power supply circuit 110 included in the control mechanism 10 shown in FIGS. 1 and 2 are mounted on the main board 11. FIG. A connector 12 to which one end of a cable 19 is attached is mounted on the main board 11 . Although one circuit board is illustrated as the main board 11 in FIG. 10, the main board 11 may be composed of two or more circuit boards.

The printhead 21 has a head 310 , a substrate 320 and a connector 350 . The other end of cable 19 is attached to connector 350 . Various signals generated by the control mechanism 10 are thereby input to the print head 21 via the cable 19 . Details of the configuration of the print head 21 and details of the signal propagated through the cable 19 will be described later.

The liquid ejecting apparatus 1 configured as described above has drive signals COM1 to COM4, reference voltage signals CGND1 to CGND4, print data signals SI1 to SI4, and latch signal LAT output from the control mechanism 10 mounted on the main board 11. , a change signal CH, a clock signal SCK, and diagnostic signals DIG-A through DIG-D. 10, a control mechanism 10 for outputting various signals for controlling the operation of the print head 21, and a cable 19 for transmitting various signals for controlling the operation of the print head 21. is an example of the printhead control circuit 15 that controls the operation of the printhead 21 that has a self-diagnosis function.

FIG. 11 is a diagram showing the structure of the cable 19. As shown in FIG. The cable 19 has a substantially rectangular shape having short sides 191 and 192 facing each other and long sides 193 and 194 facing each other, and is, for example, a flexible flat cable (FFC). The cable 19 electrically connects a plurality of terminals 195 arranged along a short side 191, a plurality of terminals 196 arranged along a short side 192, and a plurality of terminals 195 and a plurality of terminals 196. and a plurality of wirings 197 for connection.

Specifically, on the short side 191 side of the cable 19, 29 terminals 195 are arranged in order of terminals 195-1 to 195-29 from the long side 193 side to the long side 194 side. On the short side 192 of the cable 19, 29 terminals 196 are arranged in order from the long side 193 to the long side 194 in the order of terminals 196-1 to 196-29. Also, the cable 19 has 29 wirings 197 electrically connecting each of the terminals 195 and 196, wirings 197-1 to 197-29 extending from the long side 193 side to the long side 194 side. are arranged in order. The wiring 197-1 electrically connects the terminals 195-1 and 196-1. Similarly, wiring 197-k (k is any one of 1 to 29) electrically connects terminal 195-k and terminal 196-k.

Each of the wires 197-1 to 197-29 is insulated by an insulator 198 between each other and between the wires and the outside of the cable 19. FIG. The cable 19 propagates the signal input from the terminal 195-k through the wiring 197-k and outputs it from the terminal 196-k. Note that the configuration of the cable 19 shown in FIG. 11 is an example, and is not limited to this. For example, multiple terminals 195 and multiple terminals 196 may be provided on different sides of the cable 19 . Also, the number of terminals 195, terminals 196, and wires 197 provided on the cable 19 is not limited to twenty-nine.

Next, the configuration of the print head 21 will be described. FIG. 12 is a perspective view showing the configuration of the print head 21. As shown in FIG. As shown in FIG. 12, 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.

FIG. 13 is a plan view showing the structure of the ink ejection surface 311. As shown in FIG. As shown in FIG. 13, on the ink ejection surface 311, four nozzle plates 632 having nozzles 651 included in a plurality of ejection portions 600 are arranged side by side 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 four nozzle rows L1 to L4. In FIG. 13, the nozzles 651 are arranged in one row in the Y direction in the nozzle rows L1 to L4 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 L4 are provided corresponding to drive signal selection circuits 200-1 to 200-4, respectively. Specifically, the drive signal VOUT1 output by the drive signal selection circuit 200-1 is supplied to one end of the piezoelectric element 60 included in the plurality of ejection sections 600 provided in the nozzle row L1, and is supplied to the other end of the piezoelectric element 60. is supplied with the reference voltage signal CGND1. Similarly, the drive signals VOUT2 to VOUT4 output by the drive signal selection circuits 200-2 to 200-4 are supplied to one ends of the piezoelectric elements 60 of the plurality of ejection portions 600 provided in the nozzle rows L2 to L4, respectively. Reference voltage signals CGND2 to CGND4 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. 14 . FIG. 14 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. 14, 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 L4. 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. 14 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 is driven by the drive signal VOUT based on the drive signal COM, and ink is ejected from the nozzle 651 by driving the piezoelectric element 60 . The piezoelectric element 60 is not limited to the illustrated structure, and may be of any type as long as it can eject ink as the piezoelectric element 60 is displaced. Moreover, the piezoelectric element 60 is not limited to bending vibration, and may be configured to use longitudinal vibration.

Returning to FIG. 12, the substrate 320 has a surface 321 and a surface 322 different from the surface 321 . Here, the surfaces 321 and 322 are surfaces that face each other with the base material of the substrate 320 interposed therebetween. The substrate 320 has a substantially rectangular shape formed by a side 323, a side 324 facing the side 323 in the X direction, a side 325, and a side 326 facing the side 325 in the Y direction. In other words, substrate 320
has a side 323, a side 324 different from the side 323, a side 325 intersecting the sides 323 and 324, and a side 326 intersecting the sides 323 and 324 and different from the side 325. Here, the sides 325 and 326 intersecting with the sides 323 and 324 are defined by the imaginary extension lines of the edge 325 intersecting the imaginary extension lines of the edge 323 and the imaginary extension lines of the edge 324 and the imaginary extension lines of the edge 326 The line includes intersecting the imaginary extension of edge 323 and the imaginary extension of edge 324 . That is, the shape of the substrate 320 is not limited to a rectangle, and may be polygonal, such as a hexagon or an octagon, or may have a notch, an arc, or the like formed in a part thereof. .

Here, the details of the substrate 320 will be described with reference to FIGS. 15 and 16. FIG. FIG. 15 is a plan view of substrate 320 viewed from surface 322 . 16 is a plan view of the substrate 320 viewed from the surface 321. FIG. As shown in FIG. 15, the surface 322 of the substrate 320 is provided with electrode groups 330a to 330d. Specifically, each of the electrode groups 330a to 330d has a plurality of electrodes arranged side by side in the Y direction. The electrode groups 330a to 330d are arranged from the side 323 to the side 324 in the order of the electrode groups 330a, 330b, 330c, and 330d. A flexible printed circuit (FPC) (not shown) is electrically connected to each of the electrode groups 330a to 330d provided as described above.

Further, as shown in FIGS. 15 and 16, the substrate 320 is formed with FPC insertion holes 332a and 332b, which are through holes passing through the surfaces 321 and 322, and ink supply path insertion holes 331a to 331d. ing.

The FPC insertion hole 332a is located between the electrode group 330a and the electrode group 330b in the X direction, and the FPC electrically connected to the electrode group 330a and the FPC electrically connected to the electrode group 330b are inserted. be done. The FPC insertion hole 332b is located between the electrode group 330c and the electrode group 330d in the X direction, and the FPC electrically connected to the electrode group 330c and the FPC electrically connected to the electrode group 330d are inserted. be done.

The ink supply path insertion hole 331a is positioned on the 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, with the ink supply path insertion hole 331b on the side 325 side and the ink supply path insertion hole 331c on the side 326 side. are arranged side by side in the Y direction. The ink supply path insertion hole 331d is positioned on the side 324 side of the electrode group 330d in the X direction. Each of the ink supply passage insertion holes 331a to 331d has a part of an ink supply passage (not shown) that communicates with an ink supply port 661 for introducing ink to the ejection section 600 corresponding to each of the nozzle rows L1 to L4. is inserted.

15 and 16, 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 fixed portions 346 to 349 is a through hole penetrating through the surfaces 321 and 322 of the substrate 320 . The substrate 320 is fixed to the carriage 20 by attaching screws (not shown) inserted through the fixing portions 346 to 349 to the carriage 20 . Note that the fixing portions 346 to 349 are not limited to the through holes formed in the substrate 320. FIG. For example, the fixing portions 346 to 349 may be configured to fix the substrate 320 to the carriage 20 by fitting.

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

Further, as shown in FIG. 16, the 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 surface 321 side of the substrate 320, between the fixed portions 347 and 349, and on the side 326 side of the electrode groups 330a to 330d. Then, the integrated circuit 241 constituting the diagnostic circuit 240 diagnoses whether ink can be discharged normally from the nozzles 651 based on the diagnostic signals DIG-A to DIG-D.

Further, as shown in FIG. 16, the board 320 is provided with a connector 350 . The connector 350 is provided along the side 323 on the surface 321 side of the substrate 320 . That is, the connector 350 and the integrated circuit 241 forming the diagnostic circuit 240 are provided on the same surface of the substrate 320 .

Here, the configuration of connector 350 will be described with reference to FIG. 17 . FIG. 17 is a diagram showing the configuration of the connector 350. As shown in FIG. As shown in FIG. 17, 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 side 323 . Specifically, the connector 350 of the first embodiment has 29 terminals 353 arranged side by side along the side 323 . Here, the 29 terminals 353 are referred to as terminals 353-1, 353-2, . The cable attachment portion 352 is located on the board 320 side of the plurality of terminals 353 in the Z direction. The cable 19 is attached to the cable attachment portion 352 . When the cable 19 is attached to the cable attachment portion 352, each of the terminals 196-1 to 196-29 included in the cable 19 and each of the terminals 353-1 to 353-29 included in the connector 350 are electrically connected. come into direct contact.

Here, in the connector 350 shown in FIG. 17, the cable attachment portion 352 is located on the substrate 320 side in the Z direction, and the plurality of terminals 353 are located on the ink ejection 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. 18 is a diagram showing another configuration of connector 350. 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 ink that has landed on the medium P is affected by air currents caused by the movement of the carriage 20 on which the print head 21 is mounted and the transportation of the medium P. may refloat inside the liquid ejecting apparatus 1 . If the ink floating inside the liquid ejection device 1 adheres to the terminals 353 included in the connector 350 or the terminals 196 included in the cable 19 that propagates signals to the print head 21, the terminals are short-circuited. There is a risk. As a result, the waveforms of various signals input to the print head 21 are distorted, which may deteriorate the ejection accuracy of the ink ejected from the print head 21 .

As in a connector 350 shown in FIG. 18, a plurality of terminals 353 are positioned on the substrate 320 side in the Z direction, and a cable attachment portion 352 is positioned on the ink discharge surface 311 side in the Z direction, so that the cable 19 is attached to the connector 350. In this case, the terminals 353 and 196 are less likely to be exposed on the side of the ink ejection surface 311 to which the floating ink is likely to adhere. Therefore, due to the ink floating inside the liquid ejection device 1,
It is possible to reduce the possibility of a short circuit occurring between the terminals 353 included in the connector 350 or between the terminals 196 included in the cable 19 . Therefore, it is possible to reduce the possibility that the signal propagated through the cable 19 is distorted.

A specific example of electrical connection between the cable 19 and the connector 350 will now be described with reference to FIG. FIG. 19 is a diagram for explaining a specific example when the cable 19 is attached to the connector 350. FIG. As shown in FIG. 19, the terminal 353 of the connector 350 has a board mounting portion 353a, a housing insertion portion 353b, and a cable holding portion 353c. The board mounting portion 353 a is positioned below the connector 350 and provided between the housing 351 and the board 320 . The substrate attachment portion 353a is electrically connected to an electrode (not shown) provided on the substrate 320 by soldering, for example. The housing insertion portion 353b is inserted through the inside of the housing 351 . The housing insertion portion 353b electrically connects the board mounting portion 353a and the cable holding portion 353c. The cable holding portion 353 c has a curved shape protruding inside the cable attachment portion 352 . When the cable 19 is attached to the cable attachment portion 352 , the cable holding portion 353 c and the terminal 196 are electrically contacted via the contact portion 180 . Thereby, the cable 19, the connector 350, and the board 320 are electrically connected. In this case, when the cable 19 is attached, stress is generated in the curved shape formed in the cable holding portion 353c. The stress holds the cable 19 inside the cable attachment portion 352 .

As described above, the cable 19 and the connector 350 are electrically connected by bringing the terminal 196 and the terminal 353 into contact with each other via the contact portion 180 . Note that FIG. 11 shows contact portions 180-1 to 180-29 for electrically contacting terminals 196-1 to 196-29 and terminal 353 of connector 350, respectively. In the cable 19, the terminal 195-k is electrically connected to the connector 12, and the terminal 196-k is electrically connected to the connector 350 via the contact portion 180-k.

In the print head 21 configured as described above, the drive signals COM1 to COM4, the reference voltage signals CGND1 to CGND4, the print data signals SI1 to SI4, the latch signal LAT, the change signal CH, and the clock signal SCK output from the control mechanism 10 are used. are input to the print head 21 via the connector 350 . Then, it is propagated through a wiring pattern (not shown) provided on the substrate 320 and input to each of the electrode groups 330a to 330d.

Various signals input to each of the electrode groups 330a to 330d are sent to drive signal selection circuits 200- corresponding to each of the nozzle rows L1 to L4 via FPCs electrically connected to each of the electrode groups 330a to 330d. 1 to 200-4 are input. Then, the drive signal selection circuits 200-1 to 200-4 generate drive signals VOUT1 to VOUT4 based on the input signals, and supply them to the piezoelectric elements 60 included in the nozzle rows L1 to L4, respectively. As a result, various signals input to the connector 350 are supplied to the piezoelectric elements 60 included in the plurality of ejection portions 600 . Each of the drive signal selection circuits 200-1 to 200-4 may be provided inside the head 310, or may be COF (Chip On Film) mounted on the FPC.

1.7 Details of Signals Propagated by Cable Details of signals propagated between the print head control circuit 15 and the print head 21 in the liquid ejection device 1 configured as described above will be described with reference to FIG. do.

FIG. 20 is a diagram for explaining the details of the signal propagated through the cable 19. FIG. As shown in FIG. 20, the cable 19 includes wiring for propagating the drive signals COM1 to COM4, wiring for propagating the reference voltage signals CGND1 to CGND4, the temperature signal TH, the latch signal LAT, the clock signal SCK, Wiring for propagating change signal CH, print data signal SI1, and error signal XHOT, wiring for propagating diagnostic signals DIG-A to DIG-E, and wiring for propagating voltages VHV, VDD1, and VDD2. and a plurality of wirings for propagating a plurality of ground signals GND.

Specifically, the drive signals COM1 to COM4 and the reference voltage signals CGND1 to CGND4 are respectively input to the cable 19 from the terminals 195-1 to 195-8 and propagated through the wirings 197-1 to 197-8. After that, they are input to terminals 353-1 to 353-8 of connector 350 via terminals 196-1 to 196-8 and contact portions 180-1 to 180-8, respectively.

The diagnostic signal DIG-A is input from the terminal 195-25 to the cable 19, propagated through the wiring 197-25, and then to the terminal 353-25 of the connector 350 via the terminal 196-25 and the contact portion 180-25. is entered. Similarly, the latch signal LAT is also input from the terminal 195-25 to the cable 19, propagated through the wiring 197-25, and passed through the terminal 196-25 and the contact portion 180-25 to the terminal 353- of the connector 350. 25. That is, the wiring 197-25 serves both as a wiring for propagating the diagnostic signal DIG-A and a wiring for propagating the latch signal LAT, and the terminal 353-25 serves as a terminal to which the diagnostic signal DIG-A is input and a terminal for propagating the latch signal. Also serves as a terminal to which LAT is input. The contact portion 180-25 is in electrical contact with the wiring that propagates the diagnostic signal DIG-A, and is also in electrical contact with the wiring that propagates the latch signal LAT. The diagnostic signal DIG-A is an example of the second diagnostic signal in the first embodiment, and the wiring 197-25 that propagates the diagnostic signal DIG-A is an example of the second diagnostic signal propagation wiring in the first embodiment, The terminal 353-25 to which the diagnostic signal DIG-A is input is an example of the second terminal in the first embodiment, and the contact portion 180-25 electrically contacting the wiring 197-25 and the terminal 353-25 is the second terminal. It is an example of the 2nd contact part in one embodiment.

The diagnostic signal DIG-B is input from the terminal 195-23 to the cable 19, propagated through the wiring 197-23, and then to the terminal 353-23 of the connector 350 via the terminal 196-23 and the contact portion 180-23. is entered. Similarly, the clock signal SCK is also input from the terminal 195-23 to the cable 19, propagated through the wiring 197-23, and passed through the terminal 196-23 and the contact portion 180-23 to the terminal 353-23 of the connector 350. is entered in That is, the wiring 197-23 serves both as a wiring for propagating the diagnostic signal DIG-B and a wiring for propagating the clock signal SCK, and the terminal 353-23 serves as a terminal to which the diagnostic signal DIG-B is input and a terminal for propagating the clock signal. Also serves as a terminal to which SCK is input. The contact portion 180-23 is in electrical contact with the wiring that propagates the diagnostic signal DIG-B, and is also in electrical contact with the wiring that propagates the clock signal SCK. The diagnostic signal DIG-B is an example of the first diagnostic signal in the first embodiment, and the wiring 197-23 that propagates the diagnostic signal DIG-B is an example of the first diagnostic signal propagation wiring in the first embodiment, The terminal 353-23 to which the diagnostic signal DIG-B is input is an example of the first terminal in the first embodiment, and the contact portion 180-23 electrically contacting the wiring 197-23 and the terminal 353-23 is the first terminal. It is an example of the 1st contact part in 1 embodiment.

The diagnostic signal DIG-C is input from the terminal 195-21 to the cable 19, propagated through the wiring 197-21, and then to the terminal 353-21 of the connector 350 via the terminal 196-21 and the contact portion 180-21. is entered. Likewise, the change signal CH is also input from the terminal 195-21 to the cable 19, propagated through the wiring 197-21, and passed through the terminal 196-21 and the contact portion 180-21 to the terminal 353- of the connector 350. 21. That is, the wiring 197-21 is composed of a wiring for propagating the diagnostic signal DIG-C and a wiring for propagating the change signal C
H, and the terminal 353-21 also serves as a terminal to which the diagnostic signal DIG-C is input and a terminal to which the change signal CH is input. The contact portion 180-21 is in electrical contact with the wiring that propagates the diagnostic signal DIG-C, and is also in electrical contact with the wiring that propagates the change signal CH. The diagnostic signal DIG-C is an example of the third diagnostic signal in the first embodiment, and the wiring 197-21 that propagates the diagnostic signal DIG-C is an example of the third diagnostic signal propagation wiring in the first embodiment, The terminal 353-21 to which the diagnostic signal DIG-C is input is an example of the third terminal in the first embodiment, and the contact portion 180-21 electrically contacting the wiring 197-21 and the terminal 353-21 is the third terminal. It is an example of the 3rd contact part in 1 embodiment.

The diagnostic signal DIG-D is input from the terminal 195-19 to the cable 19, propagated through the wiring 197-19, and then to the terminal 353-19 of the connector 350 via the terminal 196-19 and the contact portion 180-19. is entered. Similarly, the print data signal SI1 is input from the terminal 195-19 to the cable 19, propagated through the wiring 197-19 and the contact portion 180-19, and then passed through the terminal 196-19 to the terminal 353 of the connector 350. -19. That is, the wiring 197-19 serves both as a wiring for propagating the diagnostic signal DIG-D and a wiring for propagating the print data signal SI1, and the terminal 353-19 serves as a terminal to which the diagnostic signal DIG-D is input and a wiring for propagating the print data signal SI1. It also serves as a terminal to which the data signal SI1 is input. The contact portion 180-19 is in electrical contact with the wiring that propagates the diagnostic signal DIG-D, and is also in electrical contact with the wiring that propagates the print data signal SI1. This diagnostic signal DIG-D is an example of the fourth diagnostic signal in the first embodiment, and the wiring 197-19 that propagates the diagnostic signal DIG-D is an example of the fourth diagnostic signal propagation wiring in the first embodiment, The terminal 353-19 to which the diagnostic signal DIG-D is input is an example of the fourth terminal in the first embodiment, and the contact portion 180-19 electrically contacting the wiring 197-19 and the terminal 353-19 is the fourth terminal. It is an example of the 4th contact part in one embodiment.

The diagnostic signal DIG-E is input to terminal 353-11 of connector 350 and is input to cable 19 via contact portion 180-11 and terminal 196-11. Then, the diagnostic signal DIG-E is input to the main substrate 11 from the terminal 195-11 after being propagated through the wiring 197-11. Similarly, the abnormal signal XHOT is input to the terminal 353-11 of the connector 350 and input to the cable 19 via the contact portion 180-11 and the terminal 196-11. Then, the abnormal signal XHOT is input to the main board 11 from the terminal 195-11 after being propagated through the wiring 197-11. That is, the wiring 197-11 serves both as a wiring for propagating the diagnostic signal DIG-E and a wiring for propagating the abnormal signal XHOT, and the terminal 353-11 serves as a terminal to which the diagnostic signal DIG-E is input and an abnormal signal XHOT. Also serves as a terminal to which XHOT is input. The contact portion 180-11 is in electrical contact with the wiring that propagates the diagnostic signal DIG-E, and is also in electrical contact with the wiring that propagates the abnormal signal XHOT. This diagnostic signal DIG-E is an example of the fifth diagnostic signal in the first embodiment, and the wiring 197-11 that propagates the diagnostic signal DIG-E is an example of the fifth diagnostic signal propagation wiring in the first embodiment, The terminal 353-11 to which the diagnostic signal DIG-E is input is an example of the fifth terminal in the first embodiment, and the contact portion 180-11 electrically contacting the wiring 197-11 and the terminal 353-11 is the first terminal. It is an example of the 5th contact part in one embodiment.

As described above, in the first embodiment, each of the diagnostic signals DIG-A to DIG-E and each of the latch signal LAT, clock signal SCK, change signal CH, print data signal SI1, and error signal XHOT are common. Propagated by wires. Here, each of the diagnostic signals DIG-A to DIG-E and each of the latch signal LAT, clock signal SCK, change signal CH, print data signal SI1 and error signal XHOT are propagated through common wiring and sent to common terminals. An example of an input method will be described.

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 print data signal SI1 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 print data signal SI1, and outputs them to the print head 21. do. When the liquid ejection device 1 is not in a printing state in which ink is ejected and the print head 21 performs self-diagnosis, the control circuit 100 generates diagnostic signals DIG-A to DIG-D and outputs them to the print head 21. do. As a result, the latch signal LAT, the clock signal SCK, the change signal CH, the print data signal SI1, and the diagnostic signals DIG-A to DIG-D can be propagated through common wiring. can be input to a common terminal through the contact portion of

Further, as a method of propagating the diagnostic signal DIG-E and the abnormal signal XHOT through a common wiring and inputting them to a common terminal, for example, a wiring for outputting the diagnostic signal DIG-E indicating the diagnostic result of the diagnostic circuit 240 is used. and the wiring for outputting the abnormal signal XHOT are wired-OR-connected in the print head 21, and after the wired-OR-connected signal is input to a common terminal, it propagates through the common wiring. As a result, when at least one of the temperature abnormality detection circuit 250 diagnoses whether the temperature is abnormal and the diagnosis circuit 240 diagnoses an abnormality, ink can be discharged normally from the print head 21. When the temperature abnormality detection circuit 250 and the diagnosis circuit 240 both diagnose whether the temperature is abnormal and the diagnosis circuit 240 is normal, the ink in the print head 21 is normal. An H level signal is propagated to indicate that the ink can be ejected properly.

Incidentally, 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 print data signal SI1, and the error signal XHOT are propagated through common wiring and connected to a common terminal. The method of inputting the signal to the terminal is an example, and for example, a selector or the like may be used to switch between the signal propagated through the wiring and the signal input to the terminal.

The print data signal SI, 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 the wiring through which these signals are propagated has a connection failure, etc. If this occurs, the ink ejection accuracy may deteriorate. The wiring through which such an important signal is propagated and the wiring through which the signal for the self-diagnosis of 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 used as common wiring. is input to a common terminal connected via a common contact portion, based on the self-diagnostic result of the print head 21, the print data signal SI1, the change signal CH, the latch signal LAT , the clock signal SCK and the abnormal signal XHOT can be diagnosed as to whether they are normally propagated. Furthermore, since multiple signals are propagated through one wiring and multiple signals are input to one terminal, it is possible to reduce the number of wirings to be provided on the cable 19 and the number of terminals provided on the connector 350. becomes.

Each of the print data signals SI2 to SI4 is input to the cable 19 from each of the terminals 195-17, 195-15, 195-13, and propagated through each of the wirings 197-17, 197-15, 197-13. , terminals 196-17, 196-15, 196-13, respectively, and terminals 353-17, 353-15, 353-13 of connector 350 via contact portions 180-17, 180-15, 180-13, respectively. is entered in

Voltage VHV is input to cable 19 from terminal 195-9, propagated through wiring 197-9, and then input to terminal 353-9 of connector 350 via terminal 196-9 and contact portion 180-9. . The voltage VHV is a signal having a voltage value higher than the voltage VDD1, and the voltage VHV supplied to the terminal 353-9 is supplied to the driving signal selection circuit 200. The voltage VHV is used in the drive signal selection circuit 200 as a voltage for level-shifting the logic level of the selection signal S to high-amplitude logic.

Voltage VDD1 is input from terminal 195-29 to cable 19, propagated through wiring 197-29, and then input to terminal 353-29 of connector 350 via terminal 196-29 and contact 180-29. . The voltage VDD1 supplied to the terminals 353-29 is supplied to the drive signal selection circuit 200. FIG. The voltage VDD<b>1 is used as a power supply voltage for the drive signal selection circuit 200 and is used as a voltage for generating various control signals for controlling the operation of the drive signal selection circuit 200 .

Voltage VDD2 is input from terminal 195-24 to cable 19, propagated through wiring 197-24, and then input to terminal 353-24 of connector 350 via terminal 196-24 and contact 180-24. . The voltage VDD2 supplied to the terminals 353-24 is supplied to the temperature abnormality detection circuit 250. FIG. The voltage VDD2 is used as a power supply voltage for the comparator 251 as shown in FIG. 9, and also used as a pull-up voltage for generating the abnormal signal XHOT and the diagnostic signal DIG-E. That is, when the wiring 197-11 that propagates the error signal XHOT and the diagnostic signal DIG-E and the wiring 197-24 that propagates the voltage VDD2 are electrically connected to the print head 21, the error signal XHOT and the diagnostic signal DIG-E are electrically connected to each other. The wiring 197-11 that propagates the signal DIG-E and the wiring 197-24 that propagates the voltage VDD2 are electrically connected via terminals 353-11 and 353-24 of the connector 350. FIG. In other words, in the print head 21, the terminals 353-11 and 353-24 of the connector 350 are electrically connected, and the contact portions 180-11 and 180-24 are electrically connected. It is connected to the. It should be noted that the term “electrically connected” is not limited to direct electrical connection via a wiring pattern provided on the substrate 320. For example, electrical connection via a resistor element or a capacitor element. including cases where

Here, the voltage VDD1 is an example of the first voltage signal in the first embodiment, the wiring 197-29 that propagates the voltage VDD1 is an example of the first voltage signal propagation wiring in the first embodiment, and the voltage VDD1 is an example of the sixth terminal in the first embodiment, and the contact portion 180-29 in which the wiring 197-29 and the terminal 353-29 are in electrical contact is the terminal 353-29 in the first embodiment. It is an example of a sixth contact portion. Further, the voltage VDD2 is an example of the second voltage signal in the first embodiment, the wiring 197-24 that propagates the voltage VDD2 is an example of the second voltage signal propagation wiring in the first embodiment, and the voltage VDD2 is The input terminal 353-24 is an example of the seventh terminal in the first embodiment, and the contact portion 180-24 electrically contacting the wiring 197-24 and the terminal 353-24 is the seventh terminal in the first embodiment. 7 is an example of the contact portion. Further, the voltage VHV is an example of the third voltage signal in the first embodiment, the wiring 197-9 that propagates the voltage VHV is an example of the third voltage signal propagation wiring in the first embodiment, and the voltage VHV is The input terminal 353-9 is an example of the eighth terminal in the first embodiment, and the contact portion 180-9 in which the wiring 197-9 and the terminal 353-9 are in electrical contact is the eighth terminal in the first embodiment. It is an example of 8 contact parts.

Temperature signal TH is input to terminal 353-27 of connector 350 and is input to cable 19 via contact 180-27 and terminal 196-27. Then, the temperature signal TH is input to the main board 11 from the terminal 195-27 after being propagated through the wiring 197-27.

The ground signal GND is connected to terminals 195-10, 195-12, 195-14, 195-
16, 195-18, 195-20, 195-22, 195-26, 195-28 are input to the cable 19, and wiring 197-10, 197-12, 197-14, 197-16, 197-18 , 197-20, 197-22, 197-26, 197-28, respectively, and then terminals 196-10, 196-12, 196-14, 196-16, 196-18, 196-20, 196 -22, 196-26, 196-28, respectively, and contact portions 180-10, 180-12, 180-14, 180-16, 180-18, 180-20, 180-22, 180-26, 180- 28 to terminals 353-10, 353-12, 353-14, 353-16, 353-18, 353-20, 353-22, 353-26, 353-28 of connector 350. be.

Voltages VHV and VDD1 are supplied to drive signal selection circuit 200 . The voltages VHV and VDD1 are used as voltages for generating various control signals for controlling the operation of the drive signal selection circuit 200. FIG. The drive signal selection circuit 200 generates the drive signal VOUT by selecting or deselecting the waveform of the drive signal COM. Therefore, the drive signal selection circuit 200 operates at high speed according to the ink ejection speed. Therefore, the voltages VHV and VDD1 used as the power supply voltage and various control voltages of the drive signal selection circuit 200 may be superimposed with noise according to the operation of the drive signal selection circuit 200 .

On the other hand, voltage VDD2 is supplied to temperature abnormality detection circuit 250 . The voltage VDD2 is used as a power supply voltage for the temperature abnormality detection circuit 250 and as a pull-up voltage for generating the abnormality signal XHOT and the diagnosis signal DIG-E. The logic levels of the abnormality signal XHOT and the diagnostic signal DIG-E are determined when at least one of the diagnosis result of the temperature abnormality detection circuit 250 and the diagnosis circuit 240 indicating whether the temperature is abnormal is abnormal. In this case, it becomes L level, and becomes H level when both the diagnosis result of temperature abnormality detection circuit 250 and the diagnosis result of diagnosis circuit 240 are normal. In other words, the logic levels of the abnormality signal XHOT and the diagnostic signal DIG-E do not change when the print head 21 does not have an abnormality. Therefore, it is unlikely that noise will be superimposed on the voltage VDD2 used as the power supply voltage and pull-up voltage of the temperature abnormality detection circuit 250 .

Also, the ground signal GND is a reference potential signal for a plurality of signals including voltages VHV, VDD1, and VDD2. Therefore, a current caused by a plurality of signals including voltages VHV, VDD1, and VDD2 flows through the wiring through which the ground signal GND is propagated. That is, when noise caused by the operation of the drive signal selection circuit 200 is superimposed on the voltages VHV and VDD1, a current caused by the voltages VHV and VDD1 on which the noise is superimposed flows in the wiring through which the ground signal GND is propagated. As a result, noise may be superimposed on the wiring through which the ground signal GND is propagated.

As described above, the voltage VDD2 is a signal with a more stable potential than the voltages VDD1, VHV and the ground signal GND. As shown in FIG. 20, in the print head control circuit 15 included in the liquid ejection apparatus 1 according to the first embodiment, the wiring 197-23 for propagating the diagnostic signal DIG-B and the wiring 197-23 for propagating the diagnostic signal DIG-A. 25 are arranged side by side. In the direction in which the wiring 197-23 and the wiring 197-25 are aligned, the wiring 197-24 through which the voltage VDD2, which is a stable potential, is propagated, and the wiring 197-23 through which the diagnostic signal DIG-B is propagated. located side by side. In other words, the wiring 197-24 that propagates the voltage VDD2, which is a stable potential, and the wiring 197-23 that propagates the diagnostic signal DIG-B are provided on the same cable 19 and positioned adjacent to each other. . Here, being adjacent includes that the wiring 197-23 and the wiring 197-24 included in the cable 19 are positioned adjacent to each other via the insulator 198, space, or the like.

Further, in the print head 21 provided in the liquid ejection apparatus 1 according to the first embodiment, the terminal 353-23 to which the diagnostic signal DIG-B is input and the terminal 353-25 to which the diagnostic signal DIG-A is input are arranged side by side. is provided. In the direction in which the terminals 353-23 and 353-25 are aligned, a terminal 353-24 to which a voltage VDD2 that is a signal of a stable potential is input, and a terminal 353-23 to which a clock signal SCK is input are located side by side. In other words, the terminal 353-23 to which the diagnostic signal DIG-B is input and the terminal 353-24 to which the voltage VDD2 is input are provided on the same connector 350 and positioned adjacent to each other. Here, adjacently positioned means that the terminals 353-23 and 353-24 included in the connector 350 are positioned adjacently via an insulator such as the housing 351 or the inner space of the cable attachment portion 352. Including.

That is, in the connector 350, the terminal 353-24 to which the voltage VDD2 is input is positioned near the terminal 353-23 to which the diagnostic signal DIG-B is input. In other words, in the direction in which the terminals 353-23 and 353-25 are arranged in the connector 350, the shortest distance between the terminals 353-23 and 353-24 is the terminal 353-23 and the terminal to which the voltage VDD1 is input. 353-29 and shorter than the shortest distance between the terminal 353-23 and the terminal 353-9 to which the voltage VHV is input.

Further, in the liquid ejecting apparatus 1 according to the first embodiment, the contact portion 180-23 to which the diagnostic signal DIG-B is input and the contact portion 180-25 to which the diagnostic signal DIG-A is input are provided side by side. there is In the direction in which the contact portion 180-23 and the contact portion 180-25 are aligned, the contact portion 180-24 to which the voltage VDD2, which is a stable potential signal, is input, and the contact portion to which the diagnostic signal DIG-B is input. 180-23 are located side by side. In other words, the contact portion 180-23 to which the diagnostic signal DIG-B is input and the contact portion 180-24 to which the voltage VDD2 is input are in electrical contact with the same cable 19 and the same connector 350. Included in and adjacent to the plurality of contact portions 180 . Here, being positioned adjacent to each other means that the contact portions 180-23 and 180-24 included in the plurality of contact portions 180 with which the cable 19 and the connector 350 are in electrical contact are made of an insulator such as the housing 351; Including being adjacent to each other via an inner space and an insulator 198 or the like included in the cable 19 .

That is, among the plurality of contact portions 180, the terminal 353-24 to which the voltage VDD2 is input is positioned near the contact portion 180-23 to which the diagnostic signal DIG-B is input. In other words, in the direction in which the terminals 353-23 and 353-25 are arranged in the connector 350, the shortest distance between the terminals 353-23 and 353-24 is the terminal 353-23 and the terminal to which the voltage VDD1 is input. 353-29 and shorter than the shortest distance between the terminal 353-23 and the terminal 353-9 to which the voltage VHV is input.

In the print head control circuit 15, the print head 21, and the liquid ejection device 1 configured as described above, a diagnostic signal, which is one of signals for diagnosing whether or not the print head 21 can eject ink normally, A wire through which DIG-B is propagated, a terminal to which the diagnostic signal DIG-B is input, and a wire through which a stable potential voltage VDD2 is propagated adjacent to the contact portion where the wire and the terminal are in contact, By locating the terminal to which the voltage VDD2 is input and the contact portion where the wiring and the terminal are in contact, the possibility that the waveform of the diagnostic signal DIG-B is distorted is reduced. Therefore, it is possible to reduce the possibility that the self-diagnostic function of the print head 21 will not operate normally.

Further, as shown in FIG. 20, the diagnostic signal DIG-B, which is provided adjacent to the voltage VDD2, can be propagated through a wiring 197-23 common to the clock signal SCK and input to a common terminal 353-23. preferable.

As described above, the clock signal SCK is a signal for defining the timing at which the print data signal SI is input. Therefore, if noise is superimposed on the clock signal SCK and the waveform of the clock signal SCK is distorted, the timing of the print data signal SI synchronized with the clock signal SCK varies. As a result, the ejection accuracy of ink ejected from the corresponding plurality of nozzles 651 deteriorates. If the wiring 197-23 provided adjacent to the wiring 197-24 through which the voltage VDD2 is propagated is a wiring that serves both the diagnostic signal DIG-B and the clock signal SCK, the waveform of the clock signal SCK may be distorted. is reduced. Therefore, it is possible to improve the ejection accuracy of the ink ejected from the print head 21 .

Similarly, the terminal 353-23 provided adjacent to the terminal 353-24 to which the voltage VDD2 is input is a terminal that serves both the diagnostic signal DIG-B and the clock signal SCK, thereby distorting the waveform of the clock signal SCK. is reduced. Similarly, the contact portion 180-23 provided adjacent to the contact portion 180-24 to which the voltage VDD2 is input is the contact portion to which the diagnostic signal DIG-B is input and the contact portion to which the clock signal SCK is input. This reduces the possibility that the waveform of the clock signal SCK will be distorted. Therefore, it is possible to improve the ejection accuracy of the ink ejected from the print head 21 .

Further, as shown in FIG. 20, the wiring 197-23 through which the diagnostic signal DIG-B is propagated and the wiring 197-22 through which the ground signal GND is propagated are aligned with the wiring 197-23 and the wiring 197-25. The terminal 353-23 to which the diagnostic signal DIG-B is input and the terminal 353-22 to which the ground signal GND is input are located adjacent to each other in the direction, and the terminal 353-23 and the terminal 353-25 are aligned. The contact portion 180-23, to which the diagnostic signal DIG-B is input, and the contact portion 180-22, to which the ground signal GND is input, are located adjacent to each other in the direction. are preferably positioned adjacent to each other in the direction in which the and are aligned. In other words, in the cable 19, the wiring 197-23 through which the diagnostic signal DIG-B is propagated is positioned between the wiring 197-24 through which the voltage VDD2 is propagated and the wiring 197-22 through which the ground signal GND is propagated. In the connector 350, the terminal 353-23 to which the diagnostic signal DIG-B is input is located between the terminal 353-24 to which the voltage VDD2 is input and the terminal 353-22 to which the ground signal GND is input, The contact portion 180-23 to which the diagnostic signal DIG-B is input is preferably positioned between the contact portion 180-24 to which the voltage VDD2 is input and the contact portion 180-22 to which the ground signal GND is input.

As a result, the wiring 197-22 to which the ground signal GND is propagated, the terminal 353-22 to which the ground signal GND is input, and the contact portion 180-22 to which the ground signal GND is input are connected to the voltage VDD2 by other signals. acts as a shield to reduce Therefore, it is possible to further reduce the possibility that the waveform of the diagnostic signal DIG-B will be distorted, thereby further reducing the possibility that the self-diagnostic function of the print head 21 will not operate normally. Here, the wiring 197-22 through which the ground signal GND is propagated is an example of the first ground signal propagation wiring in the first embodiment, is electrically connected to the wiring 197-22, and receives the ground signal GND. The terminal 353-22 is an example of the first ground terminal in the first embodiment, and the contact portion 180-22 in which the wiring 197-22 and the terminal 353-22 are in electrical contact is the first ground terminal in the first embodiment. It is an example of a ground contact.

Further, as shown in FIG. 20, the wiring 197-24 through which the voltage VDD2 is propagated and the wiring 197-9 through which the voltage VHV is propagated are adjacent to each other in the direction in which the wiring 197-23 and the wiring 197-25 are arranged. terminal 353-24 to which voltage VDD2 is input and voltage VHV
is not adjacent to the terminal 353-9 in the direction in which the terminals 353-23 and 353-25 are lined up. It is preferable that the contact portion 180-9 is not positioned adjacent to the contact portion 180-23 and the contact portion 180-25. Furthermore, in this case, the wiring 197-9 through which the voltage VHV is propagated and the wiring 197-10 through which the ground signal GND is propagated are located adjacent to each other in the direction in which the wiring 197-23 and the wiring 197-25 are arranged. , the terminal 353-9 to which the voltage VHV is input and the terminal 353-10 to which the ground signal GND is input are located adjacent to each other in the direction in which the terminals 353-23 and 353-25 are aligned. The contact portion 180-9 that receives the input and the contact portion 180-10 that receives the ground signal GND are preferably positioned adjacent to each other in the direction in which the contact portions 180-23 and 180-25 are aligned.

Voltage VHV is a larger voltage value than voltages VDD1 and VDD2. Therefore, when a noise component is superimposed on the voltage VHV, the signal propagated through the wiring through which the voltage VHV is propagated and the wiring adjacent thereto, the signal inputted to the terminal through which the voltage VHV is inputted and the adjacent terminal, and the voltage VHV A noise component included in voltage VHV may interfere with a signal input to a contact portion adjacent to an input contact portion. That is, the wiring 197-24, the contact portion 180-24, and the terminal 196-24 that propagate the voltage VDD2 of stable potential and input to the print head 21 are connected to the wiring 197-11 that propagates the voltage VHV and inputs to the print head 21. , the contact portion 180-11, and the terminal 196-11, noise components contained in the voltage VHV may interfere with the stable voltage VDD2. If the noise component interferes with the voltage VDD2, the waveform of the diagnostic signal DIG-B may be distorted.

Therefore, as shown in FIG. 20, the wiring 197-24 through which the voltage VDD2 is propagated is not provided adjacent to the wiring 197-9 through which the voltage VHV is propagated. Accordingly, the terminal 353-24 to which the voltage VDD2 is input is not provided, and the contact portion 180-24 to which the voltage VDD2 is input is not provided adjacent to the contact portion 180-9 to which the voltage VHV is input. It is possible to further reduce the possibility that the voltage VHV interferes with the voltage VDD2, which is a signal with a stable potential. Further, a wiring 197-10 through which the ground signal GND is propagated is provided adjacent to the wiring 197-9 through which the voltage VHV is propagated, and a ground signal GND is inputted adjacent to the terminal 353-9 through which the voltage VHV is inputted. By providing a contact portion 180-10 to which a ground signal GND is input adjacent to the contact portion 180-9 to which the voltage VHV is input, the wiring 197-10, the terminal 353-10, and contact portion 180-10 function as a shield. As a result, it is possible to reduce the possibility that voltage VHV interferes with other signals including voltage VDD2. The wiring 197-10 through which the ground signal GND is propagated is an example of the second ground signal propagation wiring in the first embodiment. The contact portion 180-10, which is an example of the second ground terminal in the first embodiment and electrically contacts the wiring 197-10 and the terminal 353-10, is an example of the second ground signal contact portion in the first embodiment. be.

Here, the connector 350 provided on the print head 21 and having terminals 353-23, 353-25, 353-21, 353-19 and 353-11 is an example of the first connector in the first embodiment. is.

1.8 Effects As described above, in the print head control circuit 15 according to the first embodiment, the diagnostic signal DIG-A and the voltage VDD2 propagated through the same cable 19 are provided side by side. Specifically, the wiring 197-23 that propagates the diagnostic signal DIG-A and the wiring 197-24 that propagates the voltage VDD2 are adjacent to each other in the direction in which the wiring 197-23 and the wiring 197-25 are arranged. To position.

The voltage VDD2 is a signal propagated through a wiring different from that of the voltage VDD1 supplied to the drive signal selection circuit 200, and is supplied to the temperature abnormality detection circuit 250 that generates the abnormality signal XHOT. The drive signal selection circuit 200 controls supply of the drive signal COM to the piezoelectric element 60 . That is, the drive signal selection circuit 200 operates at a high speed according to the ejection speed of the ink ejected from the nozzles. Therefore, noise may be superimposed on the voltage VDD1 supplied to the drive signal selection circuit 200 according to the operation of the drive signal selection circuit 200 . Then, the voltage VDD1 supplied to the drive signal selection circuit 200 is fed back through the wiring through which the ground signal GND is propagated. That is, when noise caused by the operation of the drive signal selection circuit 200 is superimposed on the voltage VDD1, a current caused by the voltage VDD1 on which the noise is superimposed flows through the wiring through which the ground signal GND is propagated.

In response to this, the temperature abnormality detection circuit 250 diagnoses the presence or absence of temperature abnormality in the print head 21 and outputs an abnormality signal XHOT. Therefore, when the printhead 21 is in the normal temperature range, the logic level does not change. Therefore, the voltage VDD2 supplied to the temperature abnormality detection circuit 250 is a signal with a more stable potential than the voltage VDD1 and the ground signal GND.

The wiring 197-24 through which the voltage VDD2 having such a stable potential is propagated and the wiring 197-23 through which the diagnostic signal DIG-B is propagated are adjacent to each other in the direction in which the wiring 197-23 and the wiring 197-25 are arranged. By positioning, it is possible to reduce the possibility that the waveform of the diagnostic signal DIG-B is distorted in the cable 19 . Therefore, the diagnostic signal DIG-B is accurately input to the diagnostic circuit 240 . This can reduce the possibility that the self-diagnostic function of the print head 21 will not operate normally.

Similarly, in the print head 21 according to the first embodiment, the terminal 353-23 to which the diagnostic signal DIG-B is input and the terminal 353-24 to which the voltage VDD2 is input are connected to the terminals 353-23 and 353-25. are positioned adjacent to each other in the direction in which they line up, and in the liquid ejection device 1 according to the first embodiment, the contact portion 180-23 to which the diagnostic signal DIG-B is input and the contact portion 180-24 to which the voltage VDD2 is input. However, since the contact portions 180-23 and 180-25 are positioned adjacent to each other in the direction in which they are aligned, it is possible to reduce the risk of distortion occurring in the waveform of the diagnostic signal DIG-B. Therefore, the diagnostic signal DIG-B is accurately input to the diagnostic circuit 240 . This can reduce the possibility that the self-diagnostic function of the print head 21 will not operate normally.

2. Second Embodiment Next, the liquid ejection device 1, the printhead control circuit 15, and the printhead 21 of the second embodiment will be described. In describing the liquid ejection apparatus 1, the print head control circuit 15, 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. Sometimes.

FIG. 21 is a diagram schematically showing the internal configuration of the liquid ejection device 1 according to the second embodiment when viewed from the Y direction. As shown in FIG. 21, the liquid ejecting apparatus 1 of the second embodiment has a main substrate 11, cables 19a and 19b, and a print head 21. FIG. That is, in the liquid ejecting apparatus 1 of the second embodiment, the main board 11 and the print head 21 are electrically connected by two cables 19a and 19b, and various signals are propagated by the cables 19a and 19b. Differs from one embodiment. The main board 11 has a connector 12a to which one end of the cable 19a is attached and a connector 12b to which one end of the cable 19b is attached. It also differs from the first embodiment in that it has a connector 360 to which the other end of 19b is attached.

Here, in the liquid ejecting apparatus 1 of the second embodiment, the control mechanism 10 for outputting various signals for controlling the operation of the print head 21 and the cable for transmitting various signals for controlling the operation of the print head 21 are described. The configuration including 19a and 19b is an example of the printhead control circuit 15 that controls the operation of the printhead 21 having the self-diagnosis function in the second embodiment.

Each of the cables 19a and 19b and the cable 19 in the first embodiment have the same configuration except for the number of terminals 195 and 196 and wiring 197 that they have. Therefore, detailed description of the configuration of the cables 19a and 19b is omitted. In the following description, the terminals 195-k provided on the cables 19a and 19b are referred to as terminals 195a-k and 195b-k, the terminals 196-k are referred to as terminals 196a-k and 196b-k, and the wiring 197 -k are referred to as wires 197a-k, 197b-k, and contacts 180-k are referred to as contacts 180a-k, 180b-k. Terminals 195a-k and 195b-k are then electrically connected to connectors 12a and 12b, respectively, and terminals 196a-k and 196b-k are connected to connectors 350 and 350 via contacts 180a-k and 180b-k. 360 is electrically connected.

Also, the print head 21 in the second embodiment will be described as having six drive signal selection circuits 200-1 to 200-6. Therefore, the print head 21 in the second embodiment has six print data signals SI1 to SI6 corresponding to the six drive signal selection circuits 200-1 to 200-6, respectively, and six drive signals COM1 to COM1 to SI6. COM6 and six reference voltage signals CGND1 to CGND6 are input.

FIG. 22 is a perspective view showing the configuration of the print head 21 in the second embodiment. As shown in FIG. 22, 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.

The substrate 320 has a surface 321 and a surface 322 facing the surface 321, a side 323, a side 324 facing the side 323 in the X direction, a side 325, and a side 325 in the Y direction. It has a substantially rectangular shape formed by opposing sides 326 . As in the first embodiment, an integrated circuit 241 that constitutes a diagnostic circuit 240 is provided on the side 326 of the surface 321 of the substrate 320 .

Board 320 is provided with connectors 350 and 360 . The connector 350 is provided along the side 323 on the surface 321 side of the substrate 320 . Also, the connector 360 is provided along the side 323 on the surface 322 side of the substrate 320 .

The configuration of connectors 350 and 360 will be described with reference to FIG. FIG. 23 is a diagram showing the configuration of connectors 350 and 360 in the second embodiment. 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 side 323 . Specifically, 26 terminals 353 are arranged side by side along the side 323 . Here, the 26 terminals 353 are referred to as terminals 353-1, 353-2, . The cable attachment portion 352 is located on the board 320 side of the plurality of terminals 353 in the Z direction. The cable 19 a is attached to the cable attachment portion 352 . When the cable 19a is attached to the cable attachment portion 352, each of the terminals 196a-1 to 196a-26 included in the cable 19a and each of the terminals 353-1 to 353-26 included in the connector 350 are electrically connected. come into direct contact. In the connector 350, as shown in FIG. 18, a plurality of terminals 353 may be positioned on the substrate 320 side of the cable attachment portion 352 in the Z direction.

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 side 323 . Specifically, 26 terminals 363 are arranged side by side along the side 323 . Here, the 26 terminals 363 are referred to as terminals 363-1, 363-2, . The cable attachment portion 362 is located on the board 320 side of the plurality of terminals 363 in the Z direction. The cable 19 b is attached to the cable attachment portion 362 . When the cable 19b is attached to the cable attachment portion 362, each of the terminals 196b-1 to 196b-26 included in the cable 19b and each of the terminals 363-1 to 363-26 included in the connector 360 are electrically connected. come into direct contact.

24 and 25, the details of the signals propagated through the cables 19a and 19b and input to the print head 21 will be described.

FIG. 24 is a diagram for explaining the details of the signal propagated through the cable 19a in the second embodiment. As shown in FIG. 24, the cable 19a includes wiring for propagating the drive signals COM1 to COM6, wiring for propagating the reference voltage signals CGND1 to CGND6, temperature signal TH, latch signal LAT, clock signal SCK, Wiring for propagating change signal CH, print data signal SI1, and error signal XHOT, wiring for propagating diagnostic signals DIG-A to DIG-E, wiring for propagating voltage VHV, and a plurality of ground signals and a plurality of wirings that propagate GND.

Specifically, the drive signals COM1 to COM6 and the reference voltage signals CGND1 to CGND6 are input to the cable 19a from the terminals 195a-1 to 195a-12, respectively, and propagated through the wirings 197a-1 to 197a-12, respectively. After that, they are input to terminals 353-1 to 353-12 of connector 350 via terminals 196a-1 to 196a-12 and contact portions 180a-1 to 180a-12, respectively.

The diagnostic signal DIG-A and the latch signal LAT are input to the cable 19a from terminals 195a-23, propagated through wires 197a-23, and then to the terminals of connector 350 via terminals 196a-23 and contacts 180a-23. 353-23. That is, the wiring 197a-23 serves both as a wiring for propagating the diagnostic signal DIG-A and a wiring for propagating the latch signal LAT. Also serves as an input terminal. The contact portion 180a-23 is in electrical contact with the wiring that propagates the diagnostic signal DIG-A, and is also in electrical contact with the wiring that propagates the latch signal LAT. This diagnostic signal DIG-A is an example of the second diagnostic signal in the second embodiment, and the wiring 197a-23 that propagates the diagnostic signal DIG-A is an example of the second diagnostic signal propagation wiring in the second embodiment, The terminal 353-23 to which the diagnostic signal DIG-A is input is an example of the second terminal in the second embodiment, and the contact portion 180a-23 electrically contacting the wiring 197a-23 and the terminal 353-23 is the second terminal. It is an example of the 2nd contact part in 2 embodiment.

The diagnostic signal DIG-B and the clock signal SCK are input from the terminal 195a-21 to the cable 19a, propagated through the wiring 197a-21, and then to the terminal of the connector 350 via the terminal 196a-21 and the contact portion 180a-21. 353-21. That is, the wiring 197a-21 serves both as a wiring for propagating the diagnostic signal DIG-B and a wiring for propagating the clock signal SCK, and the terminal 353-21 is a terminal to which the diagnostic signal DIG-B is input and the clock signal SCK. Also serves as an input terminal. The contact portion 180a-21 is in electrical contact with the wiring that propagates the diagnostic signal DIG-B, and is also in electrical contact with the wiring that propagates the clock signal SCK. The diagnostic signal DIG-B is an example of the first diagnostic signal in the second embodiment, and the wiring 197a-21 that propagates the diagnostic signal DIG-B is an example of the first diagnostic signal propagation wiring in the second embodiment, The terminal 353-21 to which the diagnostic signal DIG-B is input is an example of the first terminal in the second embodiment, and the contact portion 180a-21 electrically contacting the wiring 197a-21 and the terminal 353-21 is the first terminal. It is an example of the 1st contact part in 2 embodiment.

The diagnostic signal DIG-C and the change signal CH are input from the terminal 195a-19 to the cable 19a, propagated through the wiring 197a-19, and then to the terminal of the connector 350 via the terminal 196a-19 and the contact portion 180a-19. 353-19. That is, the wiring 197a-19 serves both as a wiring for propagating the diagnostic signal DIG-C and a wiring for propagating the change signal CH. Also serves as an input terminal. The contact portion 180a-19 is in electrical contact with the wiring that propagates the diagnostic signal DIG-C, and is also in electrical contact with the wiring that propagates the change signal CH. This diagnostic signal DIG-C is an example of the third diagnostic signal in the second embodiment, and the wiring 197a-19 that propagates the diagnostic signal DIG-C is an example of the third diagnostic signal propagation wiring in the second embodiment, The terminal 353-19 to which the diagnostic signal DIG-C is input is an example of the third terminal in the second embodiment, and the contact portion 180a-19 electrically contacting the wiring 197a-19 and the terminal 353-19 is the third terminal. It is an example of the 3rd contact part in 2 embodiment.

The diagnostic signal DIG-D and the print data signal SI1 are input from the terminal 195a-17 to the cable 19a, propagated through the wiring 197a-17, and then to the connector 350 via the terminal 196a-17 and the contact portion 180a-17. Input to terminal 353-17. That is, the wiring 197a-17 serves both as a wiring for propagating the diagnostic signal DIG-D and as a wiring for propagating the print data signal SI1, and the terminal 353-17 is a terminal to which the diagnostic signal DIG-D is input and a terminal for propagating the print data. It also serves as a terminal to which the signal SI1 is input. The contact portion 180a-17 is in electrical contact with the wiring that propagates the diagnostic signal DIG-D, and is also in electrical contact with the wiring that propagates the print data signal SI1. This diagnostic signal DIG-D is an example of the fourth diagnostic signal in the second embodiment, and the wiring 197a-17 that propagates the diagnostic signal DIG-D is an example of the fourth diagnostic signal propagation wiring in the second embodiment, The terminal 353-17 to which the diagnostic signal DIG-D is input is an example of the fourth terminal in the second embodiment, and the contact portion 180a-17 electrically contacting the wiring 197a-17 and the terminal 353-17 is the fourth terminal. It is an example of the 4th contact part in 2 embodiment.

Diagnostic signal DIG-E and fault signal XHOT are input to terminal 353-15 of connector 350 and input to cable 19a via contact 180a-15 and terminal 196a-15. Then, the diagnostic signal DIG-E and the abnormal signal XHOT are input to the main board 11 from the terminal 195a-15 after being propagated through the wiring 197a-15. That is, the wiring 197a-15 serves both as a wiring for propagating the diagnostic signal DIG-E and a wiring for propagating the abnormal signal XHOT. Also serves as an input terminal. The contact portion 180a-15 is in electrical contact with the wiring that propagates the diagnostic signal DIG-E, and is also in electrical contact with the wiring that propagates the abnormal signal XHOT. This diagnostic signal DIG-E is an example of the fifth diagnostic signal in the second embodiment, and the wiring 197a-15 that propagates the diagnostic signal DIG-E is an example of the fifth diagnostic signal propagation wiring in the second embodiment, The terminal 353-15 to which the diagnostic signal DIG-E is input is an example of the fifth terminal in the second embodiment, and the contact portion 180a-15 electrically contacting the wiring 197a-15 and the terminal 353-15 is the fifth terminal. It is an example of the 5th contact part in 2 embodiment.

Temperature signal TH is input to terminal 353-25 of connector 350 and is input to cable 19a via terminal 196a-25 and contact 180a-25. Then, the temperature signal TH is input to the main board 11 from the terminal 195a-25 after being propagated through the wiring 197a-25.

Voltage VHV enters cable 19a from terminal 195a-13, propagates through wire 197a-13, and enters terminal 353-13 of connector 350 via terminal 196a-13 and contact 180a-13. . This voltage VHV is an example of the third voltage signal in the second embodiment, and the wiring 197a-13 that propagates the voltage VHV is an example of the third voltage signal propagation wiring in the second embodiment, and receives the voltage VHV. The terminal 353-13 is an example of the eighth terminal in the second embodiment, and the contact portion 180a-13 electrically contacting the wiring 197a-13 and the terminal 353-13 is the eighth contact portion in the second embodiment. An example.

A ground signal GND is input to the cable 19a from each of terminals 195a-14, 195a-16, 195a-18, 195a-20, 195a-22, 195a-24, 195a-26, and is connected to wires 197a-14, 197a-16. , 197a-18, 197a-20, 197a-22, 197a-24 and 197a-26, respectively, and then through terminals 196a-14, 196a-16, 196a-18, 196a-20, 196a-22 and 196a. 24, 196a-26, and terminals 353 of connector 350 via contacts 180a-14, 180a-16, 180a-18, 180a-20, 180a-22, 180a-24, 180a-26, respectively; 14, 353-16, 353-18, 353-20, 353-22, 353-24, and 353-26.

Next, with reference to FIG. 25, the details of the signal propagated through the cable 19b will be described. FIG. 25 is a diagram for explaining the details of the signal propagated through the cable 19b in the second embodiment. As shown in FIG. 25, the cable 19b includes wiring for propagating the drive signals COM1 to COM6, wiring for propagating the reference voltage signals CGND1 to CGND6, and wiring for propagating the print data signals SI2 to SI6. , wiring for propagating voltages VDD1 and VDD2, and a plurality of wirings for propagating a plurality of ground signals GND.

Specifically, the drive signals COM1 to COM6 and the reference voltage signals CGND1 to CGND6 are input to the cable 19b from the terminals 195b-1 to 195b-12, respectively, and propagated through the wirings 197b-1 to 197b-12, respectively. After that, they are input to terminals 363-1 to 363-12 of connector 360 via terminals 196b-1 to 196b-12 and contact portions 180b-1 to 180b-12, respectively.

The print data signals SI2 to SI6 are input to the cable 19b from terminals 195b-24, 195b-22, 195b-20, 195b-18, 195b-16, respectively, and connected to wirings 197b-24, 197b-22, 197b-. 20, 197b-18, 197b-16 respectively, terminals 196b-24, 196b-22, 196b-20, 196b-18, 196b-16, respectively, and contacts 180b-24, 180b-22. , 180b-20, 180b-18, 180b-16 to terminals 363-24, 363-22, 363-20, 363-18, 363-16 of the connector 360, respectively.

Voltage VDD1 is input from terminal 195b-26 to cable 19b, propagated through wiring 197b-26, and then input to terminal 363-26 of connector 360 via terminal 196b-26 and contact 180b-26. . This voltage VDD1 is an example of the first voltage signal in the second embodiment, the wiring 197b-26 that propagates the voltage VDD1 is an example of the first voltage signal propagation wiring in the second embodiment, and the voltage VDD1 is an input. The terminal 363-26 connected to the terminal 363-26 is an example of the sixth terminal in the second embodiment, and the contact portion 180b-26 in which the wiring 197b-26 and the terminal 363-26 are in electrical contact is the sixth terminal in the second embodiment. It is an example of a contact part.

Voltage VDD2 is input from terminal 195b-21 to cable 19b, propagated through wiring 197b-21, and then input to terminal 363-21 of connector 360 via terminal 196b-21 and contact portion 180b-21. This voltage VDD2 is an example of the second voltage signal in the second embodiment, the wiring 197b-21 that propagates the voltage VDD2 is an example of the second voltage signal propagation wiring in the second embodiment, and the voltage VDD2 is an input. The terminal 363-21 connected to the terminal 363-21 is an example of the seventh terminal in the second embodiment, and the contact portion 180b-21 electrically contacting the wiring 197b-21 and the terminal 363-21 is the seventh terminal in the second embodiment. It is an example of a contact portion.

The ground signal GND is input to the cable 19a from each of the terminals 195b-13, 195b-15, 195b-17, 195b-19, 195b-23, 195b-25, and the wires 197b-13, 197b-15, 197b-17. , 197b-19, 197b-23, 197b-25, respectively, then terminals 196b-13, 196b-15, 196b-17, 196b-19, 196b-23, 196b-25, respectively, and contact 180b-13, 180b-15, 180b-17, 180b-19, 180b-23, 180b-25 to terminals 363-13, 363-15, 363-17, 363-19, 363- of connector 360 23, 363-25.

In the liquid ejection apparatus 1 according to the second embodiment, as shown in FIGS. 24 and 25, in the print head control circuit 15, the diagnostic signal DIG The wiring 197a-21 through which -B is propagated and the wiring 197b-21 through which the voltage VDD2, which is a stable potential, are partially overlapped. In other words, in the print head control circuit 15, the wiring 197a-21 through which the diagnostic signal DIG-B is propagated and the wiring 197b-21 through which the stable voltage VDD2 is propagated are different cables 19a and 19b. and are located opposite each other.

In the print head 21, in the direction crossing the direction in which the terminals 353-21 and 353-23 are aligned, the terminal 353-21 to which the diagnostic signal DIG-B is input and the voltage VDD2 which is a stable potential are input. The terminal 363-21 is positioned so as to partially overlap. In other words, in the print head 21, the terminal 353-21 to which the diagnostic signal DIG-B is input and the terminal 363-21 to which the voltage VDD2 is input are provided in different connectors 350 and 360 and face each other. To position.

Further, in the liquid ejecting apparatus 1, in the direction intersecting the direction in which the contact portions 180a-21 and 180a-23 are aligned, the voltage of the contact portion 180a-21 to which the diagnostic signal DIG-B is input and the stable potential It partially overlaps with the contact portion 180b-21 to which VDD2 is input. In other words, in the liquid ejecting apparatus 1, the contact portion 180a-21 to which the diagnostic signal DIG-B is input and the contact portion 180b-21 to which the voltage VDD2 is input are provided on different connectors 350 and 360, and located opposite.

As described above, the wiring 197a-21 through which the diagnostic signal DIG-B, which is one of the signals for diagnosing whether ink can be discharged normally from the print head 21, and the stable potential voltage VDD2 are connected. is positioned so that the wiring 197b-21 through which is propagated is partially overlapped in the direction intersecting the direction in which the wiring 197a-21 and the wiring 197a-23 are arranged. This reduces the possibility that the waveform of the signal DIG-B will be distorted. Similarly, the terminal 353-21 to which the diagnostic signal DIG-B is input and the terminal 363-21 to which the stable potential voltage VDD2 is input are intersected with the direction in which the terminals 353-21 and 353-23 are arranged. By locating them so that they partially overlap each other in the direction in which the diagnostic signal DIG-B is oriented, the risk of distortion occurring in the waveform of the diagnostic signal DIG-B is reduced, as in the first embodiment. Similarly, the contact portion 180a-21 to which the diagnostic signal DIG-B is input and the contact portion 180b-21 to which the stable potential voltage VDD2 is input are connected to each other. By locating them so that they partially overlap in the direction intersecting with the arranging direction, the possibility that the waveform of the diagnostic signal DIG-B will be distorted is reduced, as in the first embodiment. Therefore, it is possible to reduce the possibility that the self-diagnostic function of the print head 21 will not operate normally.

Here, facing each other means between wires 197a-k and 197b-k, between terminals 353-k and 363-k, and between contacts 180a-k and 180b-k. is not limited to the space, and substrate 320, housing 351 of connector 350, housing 361 of connector 360, and the like may intervene. In other words, facing each other means that when viewed from a particular direction, no other wiring 197 is positioned between the wirings 197a-k and 197b-k, and the terminals 353-k and 363-k , and no other contact 180 is located between the contacts 180a-k and 180b-k.

That is, a wiring 197a-21 through which a diagnostic signal DIG-B, which is one of signals for diagnosing whether or not ink can be discharged normally from the print head 21, is propagated, and a voltage VDD2 having a stable potential is propagated. When the wiring 197b-21 is provided on different cables 19a and 19b, the wiring 197a-21 and the wiring 197b-21 are positioned close to each other. In other words, the shortest distance between the wiring 197a-21 provided on the cable 19a and the wiring 197b-21 provided on the cable 19b is the distance between the wiring 197a-21 provided on the cable 19a and the wiring 197a-21 provided on the cable 19b. It is shorter than the shortest distance to other wires except wire 197b-21.

A terminal 353-21 receives a diagnostic signal DIG-B, which is one of the signals for diagnosing whether or not ink can be ejected normally from the print head 21, and a voltage VDD2 having a stable potential is transmitted to the terminal 353-21. When the terminals 363-21 are provided on different connectors 350 and 360, the terminals 353-21 and 363-21 are positioned close to each other. In other words, the shortest distance between the terminal 353-21 provided on the connector 350 and the terminal 363-21 provided on the connector 360 is the terminal 353-21 and the terminal 363-21 provided on the connector 360. Shorter than the shortest distance to other terminals 363 .

Similarly, a contact portion 180a-21 to which a diagnostic signal DIG-B, which is one of signals for diagnosing whether or not ink can be discharged normally from the print head 21, is input, and a stable potential voltage. Unlike the plurality of contact portions 180a and the plurality of contact portions 180a where the cable 19a and the connector 350 are in electrical contact, the cable 19b and the connector 360 are electrically connected to each other. When the plurality of contact portions 180b are provided in contact with each other, the contact portions 180a-21 and 180b-21 are located in the vicinity. In other words, the contact portions 180a-21 included in the plurality of contact portions 180a where the cable 19a and the connector 350 are in electrical contact, and the contact portions 180b included in the plurality of contact portions 180b where the cable 19b and the connector 360 are in electrical contact. The shortest distance between the contact portion 180b-21 and the contact portion 180b-21 is shorter than the shortest distance between the contact portion 180a-21 and the contact portions 180b other than the contact portion 180b-21 included in the plurality of contact portions 180b.

In the liquid ejection device 1 according to the second embodiment, the wiring 197a-k of the cable 19a and the wiring 197b-k of the cable 19b are positioned facing each other, and the terminal 353-k of the connector 350 and the terminal 353-k of the connector 360 are positioned to face each other. 363-k are positioned to face each other, and the contact portions 180a-k and 180b-k are positioned to face each other, but this is not the only option.

Further, as shown in FIGS. 24 and 25, the wiring 197a-21 through which the diagnostic signal DIG-B is propagated and the wiring 197a-22 through which the ground signal GND is propagated are separated from the wiring 197a-21 and the wiring 197a-23. are preferably positioned adjacent to each other in the direction in which the and are aligned. In other words, the wiring 197a-21 through which the diagnostic signal DIG-B is propagated and the wiring 197a-22 through which the ground signal GND is propagated are preferably provided on the same cable 19a and positioned adjacent to each other. . In addition, the terminal 353-21 to which the diagnostic signal DIG-B is input and the terminal 353-22 to which the ground signal GND is propagated are located adjacent to each other in the direction in which the terminals 353-21 and 353-23 are aligned. preferably. In other words, the terminal 353-21, to which the diagnostic signal DIG-B is input, is preferably provided on the same connector 350 as the terminal 353-22, to which the ground signal GND is input, and is positioned adjacent thereto. Further, the contact portion 180a-21 to which the diagnostic signal DIG-B is input and the contact portion 180a-22 to which the ground signal GND is propagated are arranged in the direction in which the contact portion 180a-21 and the contact portion 180a-23 are aligned. They are preferably located side by side. In other words, the contact portion 180a-21 to which the diagnostic signal DIG-B is input, the contact portion 180a-22 to which the ground signal GND is input, and the connector 350 with the cable 19a are electrically connected to each other. It is preferably included in and adjacent to portion 180a.

As a result, the wiring 197a-22 through which the ground signal GND is propagated, the terminal 353-22 through which the ground signal GND is input, and the contact portion 180a-22 serve as shields for reducing interference of other signals with the voltage VDD2. Function. Therefore, the possibility that the waveform of the diagnostic signal DIG-B will be distorted can be further reduced, and the possibility that the self-diagnostic function of the print head 21 will not operate normally can be further reduced. The wiring 197a-22 through which the ground signal GND is propagated is an example of the first ground signal propagation wiring in the second embodiment, and the terminal 353-22 into which the ground signal GND is input is the first ground in the second embodiment. The contact portion 180a-22, which is an example of a terminal and electrically contacts the wiring 197a-22 and the terminal 353-22, is an example of the first ground contact portion in the second embodiment.

Further, as shown in FIGS. 23 and 24, the wiring 197b-21 through which the voltage VDD2 is propagated and the wiring 197a-13 through which the voltage VHV is propagated are arranged in the same direction as the wiring 197a-21 and the wiring 197a-23. Preferably, they are not located next to each other in orthogonal directions. In other words, it is preferable that the wiring 197b-21 through which the voltage VDD2 is propagated and the wiring 197a-13 through which the voltage VHV is propagated are provided on different cables 19a and 19b, and are not positioned opposite each other. In addition, the terminal 363-21 to which the voltage VDD2 is input and the terminal 353-13 to which the voltage VHV is input are not positioned adjacent to each other in the direction perpendicular to the direction in which the terminals 353-21 and 353-23 are arranged. is preferred. In other words, it is preferable that the terminal 363-21 to which the voltage VDD2 is input and the terminal 353-13 to which the voltage VHV is input are provided in different connectors 350 and 360 and are not positioned opposite each other. Further, the contact portion 180b-21 to which the voltage VDD2 is input and the contact portion 180a-13 to which the voltage VHV is input are adjacent to each other in the direction perpendicular to the direction in which the contact portions 180a-21 and 180a-23 are arranged. It is preferred that they are not aligned. In other words, the contact portion 180b-21 to which the voltage VDD2 is input and the contact portion 180a-13 to which the voltage VHV is input are the plurality of contact portions 180a with which the cable 19a and the connector 350 are electrically contacted, Cable 19b different from 19a and a plurality of contact portions 180b different from the plurality of contact portions 180a with which a connector 360 different from the connector 350 electrically contacts, and preferably not located opposite each other. .

Furthermore, in this case, the wiring 197a-13 through which the voltage VHV is propagated and the wiring 197b-13 through which the ground signal GND is propagated are adjacent to each other in the direction crossing the direction in which the wiring 197a-21 and the wiring 197a-23 are arranged. It is preferred to be positioned side by side. In other words, the wiring 197a-13 through which the voltage VHV is propagated and the wiring 197b-13 through which the ground signal GND is propagated are preferably provided in different cables 19a and 19b and positioned opposite to each other. In addition, the terminal 353-13 to which the voltage VHV is input and the terminal 363-13 to which the ground signal GND is input are positioned adjacent to each other in the direction crossing the direction in which the terminals 353-21 and 353-23 are aligned. preferably. In other words, the terminal 353-13 to which the voltage VHV is input and the terminal 363-13 to which the ground signal GND is input are preferably provided in different connectors 350 and 360 and positioned opposite to each other. Further, the contact portion 180a-13 to which the voltage VHV is input and the contact portion 180b-13 to which the ground signal GND is input are arranged in a direction intersecting the direction in which the contact portions 180a-21 and 180a-23 are arranged. They are preferably located side by side. In other words, the contact portion 180a-13 to which the voltage VHV is input and the contact portion 180b-13 to which the ground signal GND is input are the plurality of contact portions 180a with which the cable 19a and the connector 350 are in electrical contact, A plurality of contact portions 180b different from the plurality of contact portions 180a with which a cable 19b different from the cable 19a and a connector 360 different from the connector 350 are in electrical contact with each other and may be positioned opposite each other. preferable.

Voltage VHV is a larger voltage value than voltages VDD1 and VDD2. Therefore, when a noise component is superimposed on the voltage VHV, the signal propagated through the wiring opposite to the wiring through which the voltage VHV is propagated and the signal inputted to the terminal opposite to the terminal through which the voltage VHV is inputted may Noise components contained in voltage VHV may interfere. Therefore, if the wiring 197b-21, which propagates the voltage VDD2 with a stable potential, is located opposite to the wiring 197a-13, which propagates the voltage VHV, the voltage VDD2 may interfere with the noise component included in the voltage VHV. be. If the noise component interferes with the voltage VDD2, the waveform of the diagnostic signal DIG-B may be distorted.

As shown in FIGS. 24 and 25, in the print head control circuit 15, the print head 21, and the liquid ejection device 1 according to the second embodiment, the voltage VDD2 is propagated across the wiring 197a-13 through which the voltage VHV is propagated. The terminal 363-21 to which the voltage VDD2 is input is not provided opposite to the terminal 353-13 to which the voltage VHV is input, and the contact portion 180a-13 to which the voltage VHV is input is not provided. By not providing the contact portion 180b-21 to which the voltage VDD2 is input, it is possible to reduce the possibility that the voltage VHV interferes with the voltage VDD2, which is a signal of a stable potential.

Further, a wiring 197b-13 through which a ground signal GND is propagated is provided facing the wiring 197-11 through which the voltage VHV is propagated, and a ground signal GND is inputted in opposition to the terminal 353-13 through which the voltage VHV is inputted. and a contact portion 180b-13, to which the ground signal GND is input, facing the contact portion 180a-13, to which the voltage VHV is input. interferes with other signals including voltage VDD2. The wiring 197b-13 through which the ground signal GND is propagated is an example of the second ground signal propagation wiring in the second embodiment. It is an example of the second ground terminal in the second embodiment, and the contact portion 180b-13 in which the wiring 197b-13 and the terminal 363-13 are in electrical contact is an example of the second ground contact portion in the second embodiment. .

Here, the connector 350 provided on the print head 21 and having the terminals 353-21, 353-23, 353-19 and 353-17 is an example of the first connector in the second embodiment.

3. Third Embodiment Next, the liquid ejection device 1, the printhead control circuit 15, and the printhead 21 of the third embodiment will be described. In describing the liquid ejection apparatus 1, the print head control circuit 15, and the print head 21 of the third 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. Sometimes.

FIG. 26 is a block diagram showing the electrical configuration of the liquid ejection device 1 according to the third embodiment. As shown in FIG. 26, the control circuit 100 in the third 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. The difference from the first embodiment is that CH1, CH2 and two clock signals SCK1, SCK2 for defining the timing at which the print data signal SI 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.

In the liquid ejecting apparatus 1 of 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 print data signal SI1, 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 print data signal SIn are connected via common wiring. is output 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 the diagnostic signals DIG-F to DIG-I. When the diagnostic circuit 240 determines that the print head 21 can eject ink normally based on the diagnostic signals DIG-A to DIG-D, the diagnostic signals DIG-A to DIG-C are sent through common wiring. The latch signal LAT1, the clock signal SCK1 and the change signal CH1 that are input as the latch signal cLAT1, the clock signal cSCK1 and the change signal cCH1 are output. 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 wiring common to the diagnostic signals DIG-F to DIG-H is used. The latch signal LAT2, the clock signal SCK2 and the change signal CH2 which are input via the , are output as the latch signal cLAT2, the clock signal cSCK2 and the change signal cCH2.

Here, among the signals input to the diagnostic circuit 240, the print data signal SI1 input through the wiring common to the diagnostic signal DIG-D is branched in 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 print data signal SIn, which is input through a wiring common to 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.

FIG. 27 is a diagram schematically showing the internal configuration of the liquid ejection device 1 according to the third embodiment when viewed from the Y direction. As shown in FIG. 27, the liquid ejecting apparatus 1 of the third embodiment has a main board 11, cables 19a, 19b, 19c and 19d, and a print head 21. FIG. That is, in the liquid ejecting apparatus 1 of the third embodiment, the main substrate 11 and the print head 21 are electrically connected by four cables 19a, 19b, 19c, 19d, and various signals are transmitted through the four cables 19a, 19b, 19d. It differs from the first embodiment in that it is propagated through 19c and 19d. The main substrate 11 includes a connector 12a to which one end of the cable 19a is attached, a connector 12b to which one end of the cable 19b is attached, a connector 12c to which one end of the cable 19c is attached, and a connector 12d to which one end of the cable 19d is attached. The print head 21 has a connector 350 to which the other end of the cable 19a is attached, a connector 360 to which the other end of the cable 19b is attached, a connector 370 to which the other end of the cable 19c is attached, and a connector 370 to which the other end of the cable 19d is attached. It is also different from the first embodiment in that it has a connector 380 to which is attached.

Here, in the liquid ejecting apparatus 1 of the third embodiment, the control mechanism 10 for outputting various signals for controlling the operation of the print head 21 and the cable for transmitting various signals for controlling the operation of the print head 21 are described. A configuration including 19a, 19b, 19c, and 19d is an example of the printhead control circuit 15 that controls the operation of the printhead 21 having the self-diagnosis function in the third embodiment.

Each of the cables 19a, 19b, 19c, 19d and the cable 19 in the first embodiment have the same configuration, except that the numbers of terminals 195, 196 and wires 197 are different. Therefore, detailed description of the configuration of the cables 19a, 19b, 19c, and 19d is omitted. In the following description, terminals 195-k provided on cables 19a, 19b, 19c, and 19d are referred to as terminals 195a-k, 195b-k, 195c-k, and 195d-k, respectively. 196a-k, 196b-k, 196c-k, and 196d-k, respectively, and the wires 197-k, respectively, as wires 197a-k, 197b-k, 197c-k, and 197d-k, and contacts Each of the portions 180-k are referred to as contact portions 180a-k, 180b-k, 180c-k and 180d-k. Each of the terminals 195a-k, 195b-k, 195c-k, 195b-k is electrically connected to each of the connectors 12a, 12b, 12c, 12d, and the terminals 196a-k, 196b-k, 196c- k, 196d-k are electrically connected to respective connectors 350, 360, 370, 380 via contacts 180a-k, 180b-k, 180c-k, 180d-k, respectively.

Also, the print head 21 in the third embodiment will be described as having ten drive signal selection circuits 200-1 to 200-10. Therefore, the print head 21 in the third embodiment has 10 print data signals SI1 to SI10 corresponding to the 10 drive signal selection circuits 200-1 to 200-10, respectively, and 10 drive signals COM1 to SI10. COM10 and 10 reference voltage signals CGND1 to CGND10 are input.

FIG. 28 is a perspective view showing the configuration of the print head 21 in the third embodiment. As shown in FIG. 28, 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.

The substrate 320 has a surface 321 and a surface 322 facing the surface 321, a side 323, a side 324 facing the side 323 in the X direction, a side 325, and a side 325 in the Y direction. It has a substantially rectangular shape formed by opposing sides 326 . As in the first embodiment, an integrated circuit 241 that constitutes a diagnostic circuit 240 is provided on the side 326 of the surface 321 of the substrate 320 .

Board 320 is provided with connectors 350 , 360 , 370 and 380 . The connector 350 is provided along the side 323 on the surface 321 side of the substrate 320 . Also, the connector 360 is provided along the side 323 on the surface 322 side of the substrate 320 . Here, the connector 350 and the connector 360 in the third embodiment differ from the second embodiment only in that the number of terminals included is 20, and the rest is the same as the configuration shown in FIG. Therefore, detailed description of the connector 350 and the connector 360 in the third embodiment is omitted. Note that the 20 terminals 353 arranged side by side in the connector 350 in the third embodiment are arranged in the direction along the side 323 from the side 325 side to the side 326 side in order of terminals 353-1, 353-2, , 353-20, and 20 terminals 363 arranged side by side on the connector 360 are arranged in order along the side 323 from the side 325 to the side 326. The terminals 363-1, 363 −2, . . . , 363-20.

The connector 370 is provided along the side 324 on the surface 321 side of the substrate 320 . Also, the connector 380 is provided along the side 324 on the surface 322 side of the substrate 320 .

The configuration of connectors 370 and 380 will be described with reference to FIG. FIG. 29 is a diagram showing the configuration of connectors 370 and 380 in the third embodiment. 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 side 324 . Specifically, twenty terminals 373 are arranged side by side along the side 324 . Here, the twenty terminals 373 are referred to as terminals 373-1, 373-2, . The cable attachment portion 372 is located on the board 320 side of the plurality of terminals 373 in the Z direction. The cable 19 c is attached to the cable attachment portion 372 . When the cable 19c is attached to the cable attachment portion 372, each of the terminals 196c-1 to 196c-20 included in the cable 19c and each of the terminals 373-1 to 373-20 included in the connector 370 are electrically connected. connected to each other. 18, the connector 370 may have a plurality of terminals 373 positioned on the substrate 320 side of the cable attachment portion 352 in the Z direction.

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 side 324 . Specifically, twenty terminals 383 are arranged side by side along the side 324 . Here, the twenty terminals 383 are referred to as terminals 383-1, 383-2, . The cable attachment portion 382 is located on the substrate 320 of the plurality of terminals 383 in the Z direction. The cable 19 d is attached to the cable attachment portion 382 . When the cable 19d is attached to the cable attachment portion 382, each of the terminals 196d-1 to 196d-20 included in the cable 19d and each of the terminals 383-1 to 383-20 included in the connector 380 are electrically connected. connected to each other.

30 to 33, the details of the signals propagated through the cables 19a, 19b, 19c, and 19d and input to the print head 21 will be described.

FIG. 30 is a diagram for explaining the details of the signal propagated through the cable 19a in the third embodiment. As shown in FIG. 30, the cable 19a includes wiring for propagating the drive signals COM1 to COM5, wiring for propagating the reference voltage signals CGND1 to CGND5, the temperature signal TH, the latch signal LAT1, the clock signal SCK1, Change signal CH
1 and print data signal SI1, each of diagnostic signals DIG-A to DIG-D, and a plurality of ground signals GND.

Specifically, the drive signals COM1 to COM5 and the reference voltage signals CGND1 to CGND5 are input to the cable 19a from the terminals 195a-1 to 195a-10, respectively, and propagated through the wirings 197a-1 to 197a-10, respectively. After that, they are input to terminals 353-1 to 353-10 of connector 350 via terminals 196a-1 to 196a-10 and contact portions 180a-1 to 180a-10, respectively.

Diagnostic signal DIG-A and latch signal LAT1 are input from terminal 195a-17 to cable 19a, propagated through wiring 197a-17, and then to terminal 196a-17 of connector 350 via contact 180a-17. 353-17. That is, the wiring 197a-17 serves both as a wiring for propagating the diagnostic signal DIG-A and a wiring for propagating the latch signal LAT1, and the terminal 353-17 is a terminal to which the diagnostic signal DIG-A is input and the latch signal LAT1. Also serves as an input terminal. The contact portion 180a-17 is in electrical contact with the wiring that propagates the diagnostic signal DIG-A, and is also in electrical contact with the wiring that propagates the latch signal LAT1.

The diagnostic signal DIG-B and the clock signal SCK1 are input to the cable 19a from the terminal 195a-15, propagated through the wiring 197a-15, and then to the terminal of the connector 350 via the terminal 196a-15 and the contact portion 180a-15. 353-15. That is, the wiring 197a-15 serves both as the wiring for propagating the diagnostic signal DIG-B and the wiring for propagating the clock signal SCK1, and the terminal 353-15 is the terminal to which the diagnostic signal DIG-B is input and the clock signal SCK1. Also serves as an input terminal. The contact portion 180a-15 is in electrical contact with the wiring that propagates the diagnostic signal DIG-B, and is also in electrical contact with the wiring that propagates the clock signal SCK1.

The diagnostic signal DIG-C and the change signal CH1 are input from the terminal 195a-13 to the cable 19a, propagated through the wiring 197a-13, and then to the terminal of the connector 350 via the terminal 196a-13 and the contact portion 180a-13. 353-13. That is, the wiring 197a-13 serves both as a wiring for propagating the diagnostic signal DIG-C and a wiring for propagating the change signal CH1. Also serves as an input terminal. The contact portion 180a-13 is in electrical contact with the wiring that propagates the diagnostic signal DIG-C, and is also in electrical contact with the wiring that propagates the change signal CH1.

The diagnostic signal DIG-D and the print data signal SI1 are input from the terminal 195a-11 to the cable 19a, propagated through the wiring 197a-11, and then to the connector 350 via the terminal 196a-11 and the contact portion 180a-11. Input to terminal 353-11. That is, the wiring 197a-11 serves both as a wiring for propagating the diagnostic signal DIG-D and a wiring for propagating the print data signal SI1, and the terminal 353-11 is a terminal for inputting the diagnostic signal DIG-D and a print data signal. Also serves as a terminal to which SI1 is input. The contact portion 180a-11 is in electrical contact with the wiring that propagates the diagnostic signal DIG-D, and is also in electrical contact with the wiring that propagates the print data signal SI1.

Temperature signal TH is input to terminal 353-19 of connector 350 and is input to cable 19a via contact 180a-19 and terminal 196a-19. Then, the temperature signal TH is input to the main board 11 from the terminal 195a-19 after being propagated through the wiring 197a-19.

The ground signal GND is input to the cable 19a from each of the terminals 195a-12, 195a-14, 195a-16, 195a-18, 195a-20, and the wires 197a-12, 197a-14, 197a-16, 197a-18. , 197a-20, respectively, terminals 196a-12, 196a-14, 196a-16, 196a-18, 196a-20, and contacts 180a-12, 180a-14, 180a-16, respectively. The signals are input to terminals 353-12, 353-14, 353-16, 353-18, and 353-20 of connector 350 via 180a-18 and 180a-20, respectively.

FIG. 31 is a diagram for explaining the details of the signal propagated through the cable 19b in the third embodiment. As shown in FIG. 31, the cable 19b includes wiring for propagating the drive signals COM1 to COM5, wiring for propagating the reference voltage signals CGND1 to CGND5, and wiring for propagating the print data signals SI2 to SI5. , wiring that propagates the voltage VDD1, and a plurality of wirings that propagate a plurality of ground signals GND.

Specifically, the drive signals COM1 to COM5 and the reference voltage signals CGND1 to CGND5 are input to the cable 19b from the terminals 195b-1 to 195b-10, respectively, and propagated through the wirings 197b-1 to 197b-10, respectively. After that, they are input to terminals 363-1 to 363-10 of connector 360 via terminals 196b-1 to 196b-10 and contact portions 180b-1 to 180b-10, respectively.

The print data signals SI2 to SI5 are input to the cable 19b from terminals 195b-18, 195b-16, 195b-14 and 195b-12, respectively, and connected to wirings 197b-18, 197b-16, 197b-14 and 197b-. 12, through terminals 196b-18, 196b-16, 196b-14, 196b-12, respectively, and contacts 180b-18, 180b-16, 180b-14, 180b-12, respectively. are input to terminals 363-18, 363-16, 363-14 and 363-12 of connector 360, respectively.

Voltage VDD1 is input from terminal 195b-20 to cable 19b, propagated through wiring 197b-20, and then input to terminal 363-20 of connector 360 via terminal 196b-20 and contact portion 180b-20. . This voltage VDD1 is an example of the first voltage signal in the third embodiment, the wiring 197b-20 that propagates the voltage VDD1 is an example of the first voltage signal propagation wiring in the third embodiment, and the voltage VDD1 is an input. The terminal 363-20 connected to the terminal 363-20 is an example of the sixth terminal in the third embodiment, and the contact portion 180b-20 in which the wiring 197b-20 and the terminal 363-20 are in electrical contact is the third terminal in the third embodiment. It is an example of 6 contact parts.

The ground signal GND is input to the cable 19b from each of the terminals 195b-11, 195b-13, 195b-15, 195b-17, 195b-19, and the wires 197b-11, 197b-13, 197b-15, 197b-17. , 197b-19, respectively, terminals 196b-11, 196b-13, 196b-15, 196b-17, 196b-19, and contacts 180b-11, 180b-13, 180b-15, respectively. The signals are input to terminals 363-11, 363-13, 363-15, 363-17 and 363-19 of the connector 360 via 180b-17 and 180b-19, respectively.

FIG. 32 is a diagram for explaining details of signals propagated through the cable 19c in the third embodiment. As shown in FIG. 32, the cable 19c connects the drive signals COM6 to COM10.
wiring that propagates each of the reference voltage signals CGND6 to CGND10, wiring that propagates each of the error signal XHOT, the latch signal LAT2, the clock signal SCK2, the change signal CH2, and the print data signal SI10; It includes wiring that propagates each of diagnostic signals DIG-E to DIG-I, and a plurality of wirings that propagate a plurality of ground signals GND.

Specifically, the drive signals COM6 to COM10 and the reference voltage signals CGND6 to CGND10 are input to the cable 19c from the terminals 195c-1 to 195c-10 and the contact portions 180c-1 to 180c-10, respectively. , 197c-1 to 197c-10, and then input to terminals 373-1 to 373-10 of connector 370 via terminals 196c-1 to 196c-10, respectively.

Diagnostic signal DIG-E and fault signal XHOT are input to terminal 373-12 of connector 370 and input to cable 19c via contact 180c-12 and terminal 196c-12. Then, the diagnostic signal DIG-E is input to the main substrate 11 from the terminal 195c-12 after being propagated through the wiring 197c-12. That is, the wiring 197c-12 serves both as a wiring for propagating the diagnostic signal DIG-E and a wiring for propagating the abnormal signal XHOT, and the terminal 373-12 serves as a terminal to which the diagnostic signal DIG-E is input and an abnormal signal XHOT. Also serves as a terminal to which XHOT is input. The contact portion 180c-12 is in electrical contact with the wiring that propagates the diagnostic signal DIG-E, and is also in electrical contact with the wiring that propagates the abnormal signal XHOT. This diagnostic signal DIG-E is an example of the fifth diagnostic signal in the third embodiment, and the wiring 197c-12 that propagates the diagnostic signal DIG-E is an example of the fifth diagnostic signal propagation wiring in the third embodiment, The terminal 373-12 to which the diagnostic signal DIG-E is input is an example of the fifth terminal in the third embodiment, and the contact portion 180c-12 electrically contacting the wiring 197c-12 and the terminal 373-12 is the fifth terminal. It is an example of the 5th contact part in 3 embodiment.

The diagnostic signal DIG-F and the latch signal LAT2 are input from the terminal 195c-14 to the cable 19c, propagated through the wiring 197c-14, and then to the terminal of the connector 370 via the terminal 196c-14 and the contact portion 180c-14. 373-14. That is, the wiring 197c-14 serves both as a wiring for propagating the diagnostic signal DIG-F and a wiring for propagating the latch signal LAT2. Also serves as an input terminal. The contact portion 180c-14 is in electrical contact with the wiring that propagates the diagnostic signal DIG-F, and is also in electrical contact with the wiring that propagates the latch signal LAT2. This diagnostic signal DIG-F is an example of the second diagnostic signal in the third embodiment, and the wiring 197c-14 that propagates the diagnostic signal DIG-F is an example of the second diagnostic signal propagation wiring in the third embodiment, The terminal 373-14 to which the diagnostic signal DIG-F is input is an example of the second terminal in the third embodiment, and the contact portion 180c-14 electrically contacting the wiring 197c-14 and the terminal 373-14 is the second terminal. It is an example of the 2nd contact part in 3 embodiment.

The diagnostic signal DIG-G and the clock signal SCK2 are input from the terminal 195c-16 to the cable 19c, propagated through the wiring 197c-16, and then to the terminal of the connector 370 via the terminal 196c-16 and the contact portion 180c-16. 373-16. That is, the wiring 197c-16 serves both as a wiring for propagating the diagnostic signal DIG-G and a wiring for propagating the clock signal SCK2. Also serves as an input terminal. The contact portion 180c-16 is in electrical contact with the wiring that propagates the diagnostic signal DIG-G, and is also in electrical contact with the wiring that propagates the clock signal SCK2. This diagnostic signal DIG-G is an example of the first diagnostic signal in the third embodiment, and the wiring 197c-16 that propagates the diagnostic signal DIG-G is an example of the first diagnostic signal propagation wiring in the third embodiment, Terminal 3 to which diagnostic signal DIG-G is input
73-16 is an example of the first terminal in the third embodiment, and the contact portion 180c-16 in which the wiring 197c-16 and the terminal 373-16 are in electrical contact is the first contact portion in the third embodiment. An example.

The diagnostic signal DIG-H and the change signal CH2 are input from the terminal 195c-18 to the cable 19c, propagated through the wiring 197c-18, and then to the terminal of the connector 370 via the terminal 196c-18 and the contact portion 180c-18. 373-18. That is, the wiring 197c-18 serves both as a wiring for propagating the diagnostic signal DIG-H and a wiring for propagating the change signal CH2. Also serves as an input terminal. The contact portion 180c-18 is in electrical contact with the wiring that propagates the diagnostic signal DIG-H, and is also in electrical contact with the wiring that propagates the change signal CH2. This diagnostic signal DIG-H is an example of the third diagnostic signal in the third embodiment, and the wiring 197c-18 that propagates the diagnostic signal DIG-H is an example of the third diagnostic signal propagation wiring in the third embodiment, The terminal 373-18 to which the diagnostic signal DIG-H is input is an example of the third terminal in the third embodiment, and the contact portion 180c-18 electrically contacting the wiring 197c-18 and the terminal 373-18 is the third terminal. It is an example of the 3rd contact part in 3 embodiment.

The diagnostic signal DIG-I and the print data signal SI10 are input from the terminal 195c-20 to the cable 19c, propagated through the wiring 197c-20, and then to the connector 370 via the terminal 196c-20 and the contact portion 180c-20. Input to terminal 373-20. That is, the wiring 197c-20 serves both as a wiring for propagating the diagnostic signal DIG-I and a wiring for propagating the print data signal SI10, and the terminal 373-20 is a terminal for inputting the diagnostic signal DIG-I and a print data signal. Also serves as a terminal to which SI10 is input. The contact portion 180c-20 is in electrical contact with the wiring that propagates the diagnostic signal DIG-I, and is also in electrical contact with the wiring that propagates the print data signal SI10. This diagnostic signal DIG-I is an example of the fourth diagnostic signal in the third embodiment, and the wiring 197c-20 that propagates the diagnostic signal DIG-I is an example of the fourth diagnostic signal propagation wiring in the third embodiment, The terminal 373-20 to which the diagnostic signal DIG-I is input is an example of the fourth terminal in the third embodiment, and the contact portion 180c-20 electrically contacting the wiring 197c-20 and the terminal 373-20 is the fourth terminal. It is an example of the 4th contact part in 3 embodiment.

The ground signal GND is input to the cable 19c from each of the terminals 195c-11, 195c-13, 195c-15, 195c-17, 195c-19, and the wires 197c-11, 197c-13, 197c-15, 197c-17. , 197c-19, respectively, terminals 196c-11, 196c-13, 196c-15, 196c-17, 196c-19, and contacts 180c-11, 180c-13, 180c-15, respectively. The signals are input to terminals 373-11, 373-13, 373-15, 373-17, and 373-19 of connector 370 via 180c-17 and 180c-19, respectively. Here, at least one of the wiring 197c-15 and the wiring 197c-17 that is adjacent to the wiring 197c-16 that propagates the diagnostic signal DIG-G and that propagates the ground signal GND is the first ground signal propagation in the third embodiment. At least one of the terminals 373-15 and 373-17, which is an example of the wiring and receives the ground signal GND propagated through the wiring 197c-15 and the wiring 197c-17, is the first ground terminal in the third embodiment. As an example, at least one of the wiring 197c-15 and the wiring 197c-17 and at least one of the terminal 373-15 and the terminal 373-17 are in electrical contact with each other. At least one is an example of a first ground contact.

FIG. 33 is a diagram for explaining details of signals propagated through the cable 19d in the third embodiment. As shown in FIG. 32, the cable 19d includes wiring for propagating the drive signals COM6 to COM10, wiring for propagating the reference voltage signals CGND6 to CGND10, and wiring for propagating the print data signals SI6 to DI9. , wiring that propagates voltages VHV and VDD2, and a plurality of wirings that propagate a plurality of ground signals GND.

Specifically, the drive signals COM6 to COM10 and the reference voltage signals CGND6 to CGND10 are input to the cable 19d from the terminals 195d-1 to 195d-10, respectively, and propagated through the wirings 197d-1 to 197d-10, respectively. After that, they are input to the terminals 383-1 to 383-10 of the connector 380 via the terminals 196d-1 to 196d-10 and the contact portions 180d-1 to 180d-10, respectively.

Print data signals SI6 to SI9 are input to cable 19d from terminals 195d-13, 195d-15, 195d-17, 195d-19, respectively, and connected to wiring 197d-13, 197d-15, 197d-17, 197d-. 19, through terminals 196d-13, 196d-15, 196d-17, 196d-19, respectively, and contacts 180d-13, 180d-15, 180d-17, 180d-19, respectively. are input to terminals 383-13, 383-15, 383-17 and 383-19 of connector 380, respectively.

Voltage VHV is input from terminal 195d-11 to cable 19d, propagated through wiring 197d-11, and then input to terminal 383-11 of connector 380 via terminal 196d-11 and contact portion 180d-11. . This voltage VHV is an example of the third voltage signal in the third embodiment, the wiring 197d-11 that propagates the voltage VHV is an example of the third voltage signal propagation wiring in the third embodiment, and the voltage VHV is an input The terminal 383-11 connected to the terminal 383-11 is an example of the eighth terminal in the third embodiment, and the contact portion 180d-11 in which the wiring 197d-11 and the terminal 383-11 are in electrical contact is the third terminal in the third embodiment. It is an example of 8 contact parts.

Voltage VDD2 is input from terminal 195d-16 to cable 19d, propagated through wiring 197d-16, and then input to terminal 383-16 of connector 380 via terminal 196d-16 and contact portion 180d-16. This voltage VDD2 is an example of the second voltage signal in the third embodiment, and the wiring 197d-16 that propagates the voltage VDD2 is an example of the second voltage signal propagation wiring in the third embodiment. The terminal 383-16 connected to the terminal 383-16 is an example of the seventh terminal in the third embodiment, and the contact portion 180d-16 in which the wiring 197d-16 and the terminal 383-16 are in electrical contact is the third terminal in the third embodiment. 7 is an example of the contact portion.

A ground signal GND is input to the cable 19d from each of the terminals 195d-12, 195d-14, 195d-18 and 195d-20 and propagated through each of the wirings 197d-12, 197d-14, 197d-18 and 197d-20. 196d-12, 196d-14, 196d-18, 196d-20, and contact portions 180d-12, 180d-14, 180d-18, 180d-20, respectively. 383-12, 383-14, 383-18 and 383-20. Here, the wiring 197d-10 that is adjacent to the wiring 197d-11 that propagates the voltage VHV and that propagates the ground signal GND is an example of the second ground signal propagation wiring in the third embodiment. The terminal 383-11 to which the propagated ground signal GND is input is an example of the second ground terminal in the third embodiment, and the contact portion 180d-11 electrically contacts the wiring 197d-11 and the terminal 383-11. 11 is an example of the second ground contact portion in the third embodiment.

As described above, in the liquid ejection device 1, the print head 21, and the print head control circuit 15 of the third embodiment, the wiring 197c-16 through which the diagnostic signal DIG-G is propagated and the wiring 197d-16 through which the voltage VDD2 is propagated. are provided on different cables 19c and 19d and positioned opposite each other, and the terminal 373-16 to which the diagnostic signal DIG-G is input and the terminal 383-16 to which the voltage VDD2 is input are connected to different connectors 370 and They are provided in the connector 380 and are located opposite to each other. As a result, the liquid ejection device 1, the print head 21, and the print head control circuit 15 of the third embodiment have the same effects as those of the first embodiment.

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.

REFERENCE SIGNS LIST 1 liquid ejection device 2 liquid container 10 control mechanism 11 main board 12, 12a, 12b, 12c, 12d connector 15 print head control circuit 19, 19a, 19b, 19c, 19d Cable 20 Carriage 21 Print head 30 Movement mechanism 31 Carriage motor 32 Endless belt 40 Transport mechanism 41 Transport motor 42 Transport roller 50 Drive signal output circuit 50a Drive circuit 60 Piezoelectric element 90 Linear encoder 100 Control circuit 110 Power supply circuit 180 Contact part 191, 192 Short side 193, 194 Long side 195, 196 Terminal 197 Wiring 198 Insulator 200 Drive signal selection circuit 210 Temperature detection circuit 220 Selection control circuit 222 Shift register 224 Latch circuit 226 Decoder 230 Selection circuit 232 Inverter 234 Transfer gate 240 Diagnosis circuit 241 Integrated circuit 250 Abnormal temperature detection circuit 251 Comparator 252 Reference voltage generation circuit 253 Transistor 254 Diode 255, 256 Resistor 310 Head , 311... Ink discharge surface 320... Substrate 321, 322... Surface 323, 324, 325, 326... Side 330a, 330b, 330c, 330d... Electrode group 331a, 331b, 331c, 331d... Ink supply passage insertion Holes 332a, 332b FPC insertion hole 346, 347, 348, 349 Fixed part 350 Connector 351 Housing 352 Cable mounting part 353 Terminal 353a Board mounting part 353b Housing insertion part , 353c... Cable holding part 360... Connector 361... Housing 362... Cable attachment part 363... Terminal 370... Connector 371... Housing 372... Cable attachment part 373... Terminal 380... Connector 381... Housing , 382... Cable attachment part 383... Terminal 600... Discharge part 601... Piezoelectric body 611, 612... Electrode 621... Diaphragm 631... Cavity 632... Nozzle plate 641... Reservoir 651... Nozzle, 661... Ink supply port, P... Medium

Claims (39)

a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a first terminal;
a second terminal;
a third terminal;
a fourth terminal;
a fifth terminal;
a sixth terminal;
a seventh terminal;
A first diagnostic signal input to the first terminal, a second diagnostic signal input to the second terminal, a third diagnostic signal input to the third terminal, and a fourth diagnostic signal input to the fourth terminal. a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the diagnostic signal;
a printhead control circuit for controlling the operation of a printhead having
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates a fifth diagnostic signal that is input to the fifth terminal and indicates a diagnostic result of the diagnostic circuit;
a first voltage signal propagation wiring for propagating a first voltage signal input to the sixth terminal and supplied to the drive signal selection circuit;
a second voltage signal propagation wiring for propagating a second voltage signal input to the seventh terminal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
with
In a case where the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected to the print head, the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are connected to the first voltage signal propagation wiring. electrically connected via the 5 terminal and the 7th terminal,
the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are positioned side by side;
the first diagnostic signal propagation wiring and the second voltage signal propagation wiring are positioned adjacent to each other in a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged ;
wherein the second voltage signal is a pull-up voltage for generating the fifth diagnostic signal ;
A printhead control circuit characterized by: a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a first terminal;
a second terminal;
a third terminal;
a fourth terminal;
a fifth terminal;
a sixth terminal;
a seventh terminal;
A first diagnostic signal input to the first terminal, a second diagnostic signal input to the second terminal, a third diagnostic signal input to the third terminal, and a fourth diagnostic signal input to the fourth terminal. a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the diagnostic signal;
A printhead control circuit for controlling the operation of a printhead comprising:
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates a fifth diagnostic signal that is input to the fifth terminal and indicates a diagnostic result of the diagnostic circuit;
a first voltage signal propagation wiring for propagating a first voltage signal input to the sixth terminal and supplied to the drive signal selection circuit;
a second voltage signal propagation wiring for propagating a second voltage signal input to the seventh terminal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
with
In a case where the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected to the print head, the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are connected to the first voltage signal propagation wiring. electrically connected via the 5 terminal and the 7th terminal,
the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are positioned side by side;
In a direction intersecting the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the first diagnostic signal propagation wiring and the second voltage signal propagation wiring partially overlap each other. ,
wherein the second voltage signal is a pull-up voltage for generating the fifth diagnostic signal ;
A printhead control circuit characterized by: The fifth diagnostic signal propagation wiring also serves as a wiring for propagating a signal indicating the presence or absence of an abnormal temperature of the print head,
3. The print head control circuit according to claim 1, wherein: comprising a first ground signal propagation wiring that propagates a ground signal;
In a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the first diagnostic signal propagation wiring and the first ground signal propagation wiring are positioned adjacent to each other,
4. The print head control circuit according to claim 1, wherein: a third voltage signal propagation wiring for propagating a third voltage signal having a voltage value greater than that of the first voltage signal;
In a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the second voltage signal propagation wiring and the third voltage signal propagation wiring are not positioned adjacent to each other,
5. A print head control circuit according to any one of claims 1 to 4, characterized in that: a third voltage signal propagation wiring for propagating a third voltage signal having a voltage value greater than that of the first voltage signal;
In a direction orthogonal to a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the second voltage signal propagation wiring and the third voltage signal propagation wiring do not overlap,
5. A print head control circuit according to any one of claims 1 to 4, characterized in that: comprising a second ground signal propagation wiring that propagates a ground signal;
The third voltage signal propagation wiring and the second ground signal propagation wiring are positioned adjacent to each other in a direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged,
7. A print head control circuit according to claim 5 or 6, characterized in that: comprising a second ground signal propagation wiring that propagates a ground signal;
In a direction intersecting the direction in which the first diagnostic signal propagation wiring and the second diagnostic signal propagation wiring are arranged, the third voltage signal propagation wiring and the second ground signal propagation wiring are positioned so as to partially overlap each other. ,
7. A print head control circuit according to claim 5 or 6, characterized in that: the print head has a first connector including the first terminal, the second terminal, the third terminal, the fourth terminal, and the fifth terminal; and a substrate;
The first connector and the diagnostic circuit are provided on the same surface of the substrate,
The first diagnostic signal propagation wiring, the second diagnostic signal propagation wiring, the third diagnostic signal propagation wiring, the fourth diagnostic signal propagation wiring, and the fifth diagnostic signal propagation wiring are provided on the same cable,
the cable is electrically connected to the first connector;
9. A printhead control circuit as claimed in any one of claims 1 to 8, characterized in that: The first diagnostic signal propagation wiring also serves as a wiring for propagating a clock signal,
10. A printhead control circuit as claimed in any one of claims 1 to 9. The second diagnostic signal propagation wiring also serves as a wiring for propagating a signal that defines the ejection timing of the liquid.
11. A printhead control circuit as claimed in any one of claims 1 to 10, characterized in that: The third diagnostic signal propagation wiring also serves as a wiring for propagating a signal that defines waveform switching timing of the drive signal,
12. A printhead control circuit as claimed in any one of claims 1 to 11, characterized in that: The fourth diagnostic signal propagation wiring also serves as wiring for propagating a signal that defines waveform selection of the drive signal,
13. A printhead control circuit according to any one of claims 1 to 12, characterized in that: a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
with
the fifth terminal and the seventh terminal are electrically connected,
the first terminal and the second terminal are positioned side by side;
the first terminal and the seventh terminal are positioned adjacent to each other in a direction in which the first terminal and the second terminal are arranged ;
wherein the second voltage signal is a pull-up voltage for generating the fifth diagnostic signal ;
A printhead characterized by: a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
with
the fifth terminal and the seventh terminal are electrically connected,
the first terminal and the second terminal are positioned side by side;
the first terminal and the seventh terminal partially overlap each other in a direction intersecting the direction in which the first terminal and the second terminal are arranged;
wherein the second voltage signal is a pull-up voltage for generating the fifth diagnostic signal ;
A printhead characterized by: Equipped with a temperature abnormality detection circuit that diagnoses the presence or absence of temperature abnormalities,
The fifth terminal also serves as wiring that propagates a signal indicating the presence or absence of the temperature abnormality,
16. A printhead according to claim 14 or 15, characterized in that: A first ground terminal to which a ground signal is input,
The first terminal and the first ground terminal are positioned adjacent to each other in a direction in which the first terminal and the second terminal are arranged,
17. A printhead according to any one of claims 14 to 16, characterized in that: an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input;
In a direction in which the first terminal and the second terminal are arranged, the seventh terminal and the eighth terminal are not adjacent to each other,
18. A printhead according to any one of claims 14 to 17, characterized in that: an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input;
the seventh terminal and the eighth terminal do not overlap in a direction perpendicular to the direction in which the first terminal and the second terminal are arranged;
18. A printhead according to any one of claims 14 to 17, characterized in that: A second ground terminal to which a ground signal is input,
the eighth terminal and the second ground terminal are positioned adjacent to each other in a direction in which the first terminal and the second terminal are arranged;
20. A printhead according to claim 18 or 19, characterized in that: A second ground terminal to which a ground signal is input,
The eighth terminal and the second ground terminal partially overlap each other in a direction intersecting the direction in which the first terminal and the second terminal are arranged,
20. A printhead according to claim 18 or 19, characterized in that: a first connector including the first terminal, the second terminal, the third terminal, the fourth terminal, and the fifth terminal;
a substrate;
with
The first connector and the diagnostic circuit are provided on the same surface of the substrate,
22. A printhead as claimed in any one of claims 14 to 21, characterized in that: the first terminal also serves as a terminal to which a clock signal is input;
23. A printhead as claimed in any one of claims 14 to 22, characterized in that: The second terminal also serves as a terminal to which a signal that defines ejection timing of the liquid is input.
24. A printhead as claimed in any one of claims 14 to 23, characterized in that: The third terminal also serves as a terminal to which a signal that defines waveform switching timing of the drive signal is input.
25. A printhead according to any one of claims 14 to 24, characterized in that: the fourth terminal also serves as a terminal to which a signal specifying waveform selection of the drive signal is input;
26. A printhead as claimed in any one of claims 14 to 25, characterized in that: a print head;
a printhead control circuit for controlling the operation of the printhead;
with
The print head is
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
has
The printhead control circuit comprises:
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates the fifth diagnostic signal;
a first voltage signal propagation wiring that propagates the first voltage signal;
a second voltage signal propagation wiring that propagates the second voltage signal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
has
the first diagnostic signal propagation wiring and the first terminal are in electrical contact at a first contact portion;
the second diagnostic signal propagation wiring and the second terminal are in electrical contact at a second contact portion;
the third diagnostic signal propagation wiring and the third terminal are in electrical contact at a third contact portion;
the fourth diagnostic signal propagation wiring and the fourth terminal are in electrical contact at a fourth contact portion;
the fifth diagnostic signal propagation wiring and the fifth terminal are in electrical contact at a fifth contact portion;
the first voltage signal propagation wiring and the sixth terminal are in electrical contact at a sixth contact portion;
the second voltage signal propagation wiring and the seventh terminal are in electrical contact at a seventh contact portion;
the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected via the fifth terminal, the fifth contact portion, the seventh contact portion, and the seventh terminal;
The first contact portion and the second contact portion are positioned side by side,
the first contact portion and the seventh contact portion are positioned adjacent to each other in a direction in which the first contact portion and the second contact portion are arranged ;
wherein the second voltage signal is a pull-up voltage for generating the fifth diagnostic signal ;
A liquid ejection device characterized by: a print head;
a printhead control circuit for controlling the operation of the printhead;
with
The print head is
a drive element that is driven based on the drive signal to eject liquid from the nozzle;
a drive signal selection circuit that controls supply of the drive signal to the drive element;
a diagnostic circuit for diagnosing whether or not the liquid can be discharged normally based on the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a first terminal to which the first diagnostic signal is input;
a second terminal to which the second diagnostic signal is input;
a third terminal to which the third diagnostic signal is input;
a fourth terminal to which the fourth diagnostic signal is input;
a fifth terminal to which a fifth diagnostic signal indicating a diagnostic result of the diagnostic circuit is input;
a sixth terminal to which a first voltage signal supplied to the drive signal selection circuit is input;
a seventh terminal to which the second voltage signal is input;
has
The printhead control circuit comprises:
a first diagnostic signal propagation wiring that propagates the first diagnostic signal;
a second diagnostic signal propagation wiring that propagates the second diagnostic signal;
a third diagnostic signal propagation wiring that propagates the third diagnostic signal;
a fourth diagnostic signal propagation wiring that propagates the fourth diagnostic signal;
a fifth diagnostic signal propagation wiring that propagates the fifth diagnostic signal;
a first voltage signal propagation wiring that propagates the first voltage signal;
a second voltage signal propagation wiring that propagates the second voltage signal;
a diagnostic signal output circuit that outputs the first diagnostic signal, the second diagnostic signal, the third diagnostic signal, and the fourth diagnostic signal;
a drive signal output circuit that outputs the drive signal;
has
the first diagnostic signal propagation wiring and the first terminal are in electrical contact at a first contact portion;
the second diagnostic signal propagation wiring and the second terminal are in electrical contact at a second contact portion;
the third diagnostic signal propagation wiring and the third terminal are in electrical contact at a third contact portion;
the fourth diagnostic signal propagation wiring and the fourth terminal are in electrical contact at a fourth contact portion;
the fifth diagnostic signal propagation wiring and the fifth terminal are in electrical contact at a fifth contact portion;
the first voltage signal propagation wiring and the sixth terminal are in electrical contact at a sixth contact portion;
the second voltage signal propagation wiring and the seventh terminal are in electrical contact at a seventh contact portion;
the fifth diagnostic signal propagation wiring and the second voltage signal propagation wiring are electrically connected via the fifth terminal, the fifth contact portion, the seventh contact portion, and the seventh terminal;
the first contact portion and the seventh contact portion partially overlap each other in a direction intersecting the direction in which the first contact portion and the second contact portion are arranged ;
wherein the second voltage signal is a pull-up voltage for generating the fifth diagnostic signal ;
A liquid ejection device characterized by: The print head has a temperature abnormality detection circuit for diagnosing the presence or absence of temperature abnormality,
The fifth diagnostic signal propagation wiring also serves as a wiring for propagating a signal indicating the presence or absence of the temperature abnormality,
29. The liquid ejecting apparatus according to claim 27 or 28, characterized in that: The print head has a first ground terminal to which a ground signal is input,
The printhead control circuit has a first ground signal propagation line that propagates a ground signal,
the first ground signal propagation wiring and the first ground terminal are in electrical contact at a first ground contact portion;
The first contact portion and the first ground contact portion are positioned adjacent to each other in a direction in which the first contact portion and the second contact portion are aligned,
30. The liquid ejecting apparatus according to any one of claims 27 to 29, characterized by: The print head has an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input,
The print head control circuit has a third voltage signal propagation line that propagates the third voltage signal,
the third voltage signal propagation wiring and the eighth terminal are in electrical contact at an eighth contact portion;
In the direction in which the first contact portion and the second contact portion are arranged, the seventh contact portion and the eighth contact portion are not positioned adjacent to each other,
31. The liquid ejecting apparatus according to any one of claims 27 to 30, characterized in that: The print head has an eighth terminal to which a third voltage signal having a voltage value higher than that of the first voltage signal is input,
The print head control circuit has a third voltage signal propagation line that propagates the third voltage signal,
the third voltage signal propagation wiring and the eighth terminal are in electrical contact at an eighth contact portion;
In a direction perpendicular to the direction in which the first contact portion and the second contact portion are arranged, the seventh contact portion and the eighth contact portion do not overlap,
31. The liquid ejecting apparatus according to any one of claims 27 to 30, characterized in that: The print head has a second ground terminal to which a ground signal is input,
The printhead control circuit has a second ground signal propagation line that propagates a ground signal,
the second ground signal propagation wiring and the second ground terminal are in electrical contact at a second ground contact portion;
The eighth contact portion and the second ground contact portion are positioned adjacent to each other in a direction in which the first contact portion and the second contact portion are aligned,
33. The liquid ejecting apparatus according to claim 31 or 32, characterized by: The print head has a second ground terminal to which a ground signal is input,
The printhead control circuit has a second ground signal propagation line that propagates a ground signal,
the second ground signal propagation wiring and the second ground terminal are in electrical contact at a second ground contact portion;
In a direction intersecting the direction in which the first contact portion and the second contact portion are aligned, the eighth contact portion and the second ground contact portion partially overlap each other,
33. The liquid ejecting apparatus according to claim 31 or 32, characterized by: the print head has a first connector having the first terminal, the second terminal, the third terminal, the fourth terminal, and the fifth terminal; and a substrate;
the first connector and the diagnostic circuit are provided on the same side of the substrate;
The first diagnostic signal propagation wiring, the second diagnostic signal propagation wiring, the third diagnostic signal propagation wiring, the fourth diagnostic signal propagation wiring, and the fifth diagnostic signal propagation wiring are provided on the same cable,
the cable is electrically connected to the first connector;
35. The liquid ejecting apparatus according to any one of claims 27 to 34, characterized in that: The first diagnostic signal propagation wiring also serves as a wiring for propagating a clock signal,
36. The liquid ejecting apparatus according to any one of claims 27 to 35, characterized in that: The second diagnostic signal propagation wiring also serves as a wiring for propagating a signal that defines the ejection timing of the liquid.
37. The liquid ejecting apparatus according to any one of claims 27 to 36, characterized by: The third diagnostic signal propagation wiring also serves as a wiring for propagating a signal that defines waveform switching timing of the drive signal,
38. The liquid ejecting apparatus according to any one of claims 27 to 37, characterized by: The fourth diagnostic signal propagation wiring also serves as wiring for propagating a signal that defines waveform selection of the drive signal,
39. The liquid ejecting apparatus according to any one of claims 27 to 38, characterized by:

Images