JP2021020405A - Liquid discharge device and driving method for liquid discharge device - Google Patents

Abstract

To suppress liquid from being filled into an energy generation chamber and then left as it is.SOLUTION: A liquid discharge device comprises: a nozzle for discharging liquid; an energy generation chamber communicating with the nozzle; an energy generation element, provided in the energy generation chamber, which generates energy for discharging liquid through the nozzle; a circulation mechanism that circulates liquid between the energy generation chamber and outside of the energy generation chamber; a discharging control part that executes liquid discharging operation by which the energy generation element is driven to discharge liquid through the nozzle; and an air introduction control part that executes air introduction operation by which air is introduced into the energy generation chamber without driving the energy generation element.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a liquid discharge device and a method for driving the liquid discharge device.

A liquid discharge device such as a printer includes a liquid discharge head that discharges liquid to a recording medium or the like. For example, Patent Document 1 includes a nozzle for discharging a liquid, a pressure generating chamber communicating with the nozzle, and a common liquid chamber communicating with the pressure generating chamber, and includes a liquid having a circulation mechanism for circulating the liquid in the common liquid chamber. The discharge head is disclosed.

Japanese Unexamined Patent Publication No. 2012-143948

In the liquid discharge device, it may be necessary to forcibly discharge the liquid in the pressure generating chamber when the power is turned off. However, even in such a case, in the liquid discharge device described in Patent Document 1, the liquid may remain filled in the pressure generating chamber. The liquid filled in the pressure generating chamber freezes and expands in a low temperature environment such as below freezing point, and the pressure generating chamber may be damaged.

According to one embodiment of the present disclosure, a liquid discharge device is provided. This liquid discharge device is provided in a nozzle for discharging a liquid, an energy generation chamber communicating with the nozzle, and the energy generation chamber, and is an energy generation element for generating energy for discharging the liquid from the nozzle. A circulation mechanism for circulating the liquid between the energy generation chamber and the outside of the energy generation chamber, and a discharge operation for driving the energy generation element to discharge the liquid from the nozzle. It includes a control unit and an air introduction control unit that executes an air introduction operation for introducing air into the energy generation chamber without driving the energy generation element.

The explanatory view which shows the schematic structure of the liquid discharge device as one Embodiment of this disclosure. Explanatory drawing which shows schematic structure of the circulation mechanism. Explanatory drawing which shows disassembled view of the main component of a liquid discharge head. FIG. 3 is a cross-sectional view of the liquid discharge head along line 4-4 in FIG. Explanatory drawing which shows typically the schematic structure of the control unit. The flowchart which shows the processing procedure of the liquid discharge operation processing. The flowchart which shows the processing procedure of the air introduction control processing. The flowchart which shows the processing procedure of the air introduction control processing in 2nd Embodiment. The flowchart which shows the processing procedure of the air introduction control processing in 3rd Embodiment. The explanatory view which shows typically the schematic structure of the circulation mechanism provided in the liquid discharge device in 4th Embodiment. The flowchart which shows the processing procedure of the air introduction control processing in 4th Embodiment. The explanatory view which shows typically the schematic structure of the circulation mechanism provided in the liquid discharge device in 5th Embodiment. The flowchart which shows the processing procedure of the air introduction control processing in 5th Embodiment. An explanatory view schematically showing a schematic configuration of a circulation mechanism included in the liquid discharge device according to the sixth embodiment. The explanatory view which shows typically the schematic structure of the control unit included in the liquid discharge device in 7th Embodiment.

A. First Embodiment:
A1. Device configuration:
FIG. 1 is an explanatory diagram showing a schematic configuration of a liquid discharge device 100 as an embodiment of the present disclosure. The liquid ejection device 100 is an inkjet printing apparatus that prints by ejecting droplets of ink, which is an example of a liquid, onto a medium 12. In addition to printing paper, the medium 12 can be printed on any material such as a resin film or cloth. In FIG. 1, of the X, Y, and Z directions orthogonal to each other, the Y direction is the direction in which the nozzles 226 are lined up in the nozzle row 226s described later, the X direction is the direction in which the nozzle rows 226s are lined up, and the Z direction is. The direction is parallel to the vertical direction. When specifying the direction, the positive direction is "+" and the negative direction is "-", and the positive and negative signs are used together in the direction notation. In the present embodiment, the X direction is the main scanning direction which is the moving direction of the liquid discharge head 200. The Y direction is a sub-scanning direction which is a medium feed direction orthogonal to the main scanning direction. The −Z direction is the ink ejection direction. The arrows indicating each direction are shown so as to correspond to FIG. 1 in the figure referred to later.

The liquid discharge device 100 includes a liquid storage unit 14, a transfer mechanism 22 for delivering the medium 12, a control unit 80, a head moving mechanism 24, and a liquid discharge head 200. The liquid storage unit 14 individually stores a plurality of types of ink supplied to the liquid discharge head 200. As the liquid storage unit 14, a bag-shaped liquid pack made of a flexible film, an ink tank capable of replenishing ink, and the like can be used.

The control unit 80 includes one or a plurality of processing circuits such as a CPU (Central Processing Unit) and an FPGA (Field Programmable Gate Array) and a storage circuit such as a semiconductor memory, and controls the operation of the entire liquid discharge device 100. The configuration of the control unit 80 will be described later.

The transport mechanism 22 operates under the control of the control unit 80 and transports the medium 12 in the + Y direction. The head moving mechanism 24 includes a transport belt 23 spanned in the X direction over the print range of the medium 12, and a carriage 25 that accommodates the liquid discharge head 200 and fixes it to the transport belt 23. The head moving mechanism 24 operates under the control of the control unit 80, and moves the liquid discharge head 200 back and forth together with the carriage 25 along the main scanning direction X. When the carriage 25 reciprocates, the carriage 25 is guided by a guide rail (not shown). The liquid storage unit 14 may be mounted on the carriage 25 together with the liquid discharge head 200.

The liquid ejection head 200 has a plurality of nozzles 226 for ejecting ink. The nozzles 226 form a nozzle row 226s arranged side by side in the Y direction. The nozzle 226 has a discharge port for ejecting ink at a position facing the medium 12. The liquid discharge head 200 is prepared for each color of the ink stored in the liquid storage unit 14, and the ink supplied from the liquid storage unit 14 is directed from the plurality of nozzles 226 toward the medium 12 under the control of the control unit 80. Discharge. An image or the like is printed on the medium 12 by the liquid discharge from the nozzle 226 during the reciprocating movement of the liquid discharge head 200. The arrow shown by the broken line in FIG. 1 schematically represents the movement of ink between the liquid storage unit 14 and the liquid ejection head 200. In the liquid discharge device 100, the circulation mechanism 250 described later circulates the ink between the liquid storage unit 14 and the liquid discharge head 200 to suppress thickening of the ink and sedimentation of solid components and the like contained in the ink. ing.

FIG. 2 is an explanatory diagram schematically showing a schematic configuration of the circulation mechanism 250. The circulation mechanism 250 connects the liquid discharge head 200 and the liquid storage unit 14, circulates ink between the liquid discharge head 200 and the liquid storage unit 14 during the printing operation of the liquid discharge device 100, and then recirculates the ink. It is supplied to the liquid discharge head 200. The circulation mechanism 250 includes a supply flow path 251, a recovery flow path 253, a first pressure generation mechanism P1, and a second pressure generation mechanism P2.

The supply flow path 251 connects the liquid storage unit 14 and the energy generation chamber 213 described later included in the liquid discharge head 200, and supplies the ink in the liquid storage unit 14 to the energy generation chamber 213. The recovery flow path 253 connects the energy generation chamber 213 and the liquid storage unit 14, and collects the ink in the energy generation chamber 213 to the liquid storage unit 14. In the following description, in the supply flow path 251 the liquid accommodating portion 14 side is upstream and the liquid discharge head 200 side is downstream. In the recovery flow path 253, the liquid discharge head 200 side is upstream and the liquid storage unit 14 side is downstream.

The first pressure generating mechanism P1 is provided in the supply flow path 251. The first pressure generation mechanism P1 operates in response to the control signal of the control unit 80, and sends the ink supplied from the liquid storage unit 14 to the energy generation chamber 213. The second pressure generation mechanism P2 is provided in the recovery flow path 253. The second pressure generation mechanism P2 operates in response to the control signal of the control unit 80, and sends the ink discharged from the energy generation chamber 213 to the liquid storage unit 14. In the present embodiment, positive pressure is applied to the first pressure generating mechanism P1 and negative pressure is applied to the second pressure generating mechanism P2, so that the ink circulates in the circulation mechanism 250. The first pressure generating mechanism P1 and the second pressure generating mechanism P2 are composed of a positive displacement pump. The first pressure generating mechanism P1 and the second pressure generating mechanism P2 may be a rotary pump such as a gear pump or a vane pump, or a reciprocating pump such as a plunger pump or a piston pump, instead of the positive displacement pump. A diaphragm pump may be used.

Although the configuration in which the ink is circulated between the liquid ejection head 200 and the liquid accommodating portion 14, the configuration in which the ink is circulated between the liquid ejection head 200 and the outside of the liquid ejection head 200 may be used. For example, a second liquid storage unit may be provided outside the liquid discharge head 200 separately from the liquid storage unit 14, and ink may be circulated between the liquid discharge head 200 and the second liquid storage unit. Further, for example, an annular flow path (a flow path having a shape in which the upstream end of the supply flow path 251 and the downstream end of the recovery flow path 253 shown in FIG. 2 are directly connected) is communicated with the liquid discharge head 200. Ink may be circulated between the liquid ejection head 200 and the annular flow path.

FIG. 3 is an explanatory view showing the main constituent members of the liquid discharge head 200 in an exploded view. FIG. 4 is a cross-sectional view of the liquid discharge head 200 along the line 4-4 in FIG. As shown in FIGS. 3 and 4, the liquid discharge head 200 protects the flow path substrate 212 in which the flow path is formed, the energy generation chamber substrate 214 in which the energy generation chamber 213 is formed, and the energy generation element 215. The protective substrate 216, the introduction flow path substrate 217 provided with the first inlet 223 connected to the supply flow path 251 and the outlet flow path substrate 218 provided with the first outlet 231 connected to the recovery flow path 253. A nozzle substrate 220 on which a plurality of nozzles 226 are formed, a first compliance substrate 221 and a second compliance substrate 222 are provided.

As shown in FIG. 3, the flow path substrate 212 is a plate-shaped member elongated in the Y direction in a plan view from the Z direction. The introduction flow path board 217 and the lead flow path board 218 are attached to both ends of the flow path board 212 in the + Z direction in the X direction. The energy generation chamber substrate 214 and the protective substrate 216 are laminated and fixed in the region between the introduction flow path substrate 217 and the lead flow path substrate 218. A nozzle board 220 is joined to the surface of the flow path board 212 in the −Z direction at the center in the X direction, and a first compliance board 221 is joined to the + X direction side with the nozzle board 220 in between, and the −X direction side. A second compliance board 222 is joined to the surface.

As shown in FIG. 4, the introduction flow path substrate 217 has an introduction liquid chamber 224 inside. The introduction liquid chamber 224 opens in the −Z direction surface of the introduction flow path substrate 217 and communicates with the first liquid chamber 227 formed in the flow path substrate 212. The first common liquid chamber 234 is formed by communicating the first liquid chamber 227 and the introduction liquid chamber 224. A first inlet 223 is provided at the center in the Y direction on the surface of the introduction flow path substrate 217 in the + Z direction. The first inlet 223 communicates with the supply flow path 251. As shown by the white arrows, the ink supplied from the liquid storage unit 14 via the supply flow path 251 flows into the first common liquid chamber 234 via the first inlet 223.

As shown in FIGS. 3 and 4, in the flow path substrate 212, in order from the + X direction side to the −X direction side, the above-mentioned first liquid chamber 227, first individual communication passage 228, nozzle communication passage 229, It has a second individual passage 230 and a second liquid chamber 233. The first liquid chamber 227 is a liquid chamber that extends along the Y direction, which is the rowing direction of the nozzles 226, and communicates with a plurality of energy generation chambers 213. The first individual communication passage 228 is a flow path for individually communicating the energy generation chamber 213 and the first liquid chamber 227, and is provided corresponding to each energy generation chamber 213.

As shown in FIG. 4, the energy generation chamber 213 is a liquid chamber elongated in the X direction, and is open to the surface of the energy generation chamber substrate 214 on the −Z direction side. By joining the energy generation chamber substrate 214 to the + Z direction surface of the flow path substrate 212, the opening is closed and the energy generation chamber 213 is defined. In the energy generation chamber substrate 214, a flexible diaphragm 219 is provided at a position corresponding to the energy generation chamber 213.

The diaphragm 219 is a thin plate member that is displaced according to the drive of the energy generating element 215. An energy generation element 215 is provided in a portion of the diaphragm 219 corresponding to the energy generation chamber 213.

The energy generation element 215 is individually provided in the energy generation chamber 213. The energy generation element 215 generates energy for ejecting ink from the nozzle 226. The energy generation element 215 is deformed in response to a control signal from the control unit 80. The volume of the energy generation chamber 213 increases or decreases due to the deformation of the diaphragm 219 with the deformation of the energy generation element 215. As a result, a pressure change occurs in the ink in the energy generation chamber 213, and droplets are ejected from the nozzle 226. The energy generating element 215 is composed of a laminated piezoelectric element, a piezoelectric actuator composed of a thin film piezoelectric element, a thermal actuator using an electrothermal conversion element such as a heat generating resistor, a vibrating plate and a counter electrode. An electrostatic actuator may be used.

The first compliance substrate 221 is a plate-shaped member elongated in the Y direction in a plan view from the Z direction. The first compliance substrate 221 is a thin film member formed of refenylene sulfide (PPS), aromatic polyamide, or the like. The first compliance substrate 221 absorbs pressure vibration propagating from each energy generation chamber 213 to the first common liquid chamber 234 when ink droplets are ejected from each nozzle 226.

The nozzle communication passage 229 is a flow path that penetrates the flow path substrate 212 in the Z direction. The nozzle communication passage 229 communicates the nozzle 226 with the energy generation chamber 213 corresponding to the nozzle 226.

The nozzle substrate 220 is joined to the surface of the flow path substrate 212 in the −Z direction to close the openings of the nozzle communication passage 229 and the second individual communication passage 230. In the nozzle substrate 220, for example, a plurality of nozzles 226 are arranged side by side by performing dry etching, wet etching, or the like on a silicon (Si) single crystal substrate. The nozzle 226 is a substantially circular through hole that penetrates the nozzle substrate 220 in the Z direction.

The second individual passage 230 is formed corresponding to each nozzle 226. The second individual passage 230 is formed in a groove shape by subjecting the flow path substrate 212 to wet etching or the like. The end of the second individual communication passage 230 on the + X direction side communicates with the nozzle communication passage 229, and the end portion on the −X direction side communicates with the second liquid chamber 233.

As shown in FIG. 3, the second liquid chamber 233 is a liquid chamber extending along the Y direction. As shown in FIG. 4, the second liquid chamber 233 communicates with the plurality of nozzles 226 via the second individual communication passage 230. The opening of the second liquid chamber 233 on the −X direction side communicates with the lead liquid chamber 235 of the lead flow path substrate 218. The second common liquid chamber 236 is formed by communicating the second liquid chamber 233 and the lead liquid chamber 235. The opening of the second liquid chamber 233 on the −Z direction side is closed by the second compliance substrate 222.

The second compliance substrate 222 absorbs pressure vibration propagating from each energy generation chamber 213 side to the second common liquid chamber 236 when ink droplets are ejected from each nozzle 226.

The lead-out flow path substrate 218 has a lead-out liquid chamber 235 inside. The lead-out liquid chamber 235 opens on the surface of the lead-out flow path substrate 218 on the −Z direction side and communicates with the second liquid chamber 233 of the flow path substrate 212. The second common liquid chamber 236 is formed by communicating the second liquid chamber 233 and the lead liquid chamber 235. As shown by the hatched arrows, the ink in the second common liquid chamber 236 is sent out from the first outlet 231 to the recovery flow path 253 and returned to the liquid storage unit 14.

The protective substrate 216 is formed corresponding to the formation region of each energy generating element 215 provided on the diaphragm 219. The protective substrate 216 has an accommodating empty space 238 inside. The energy generation element 215 is housed in the storage space 238 and is joined to the surface of the energy generation chamber substrate 214 on the + Z direction side. The protective substrate 216 has a lead electrode 240 drawn from the energy generating element 215 and a through-hole 239 that penetrates the protective substrate 216 in the Z direction.

FIG. 5 is an explanatory diagram schematically showing a schematic configuration of the control unit 80. The control unit 80 includes a CPU 81, a memory 95, and an input / output interface 91. The CPU 81, the memory 95, and the input / output interface 91 are bidirectionally connected to each other via the internal bus 93. The CPU 81 functions as a control unit 82, a discharge control unit 83, and an air introduction control unit 84 by executing a control program stored in the memory 95.

The control unit 82 comprehensively controls the transport mechanism 22, the head moving mechanism 24, and the liquid discharge head 200. Specifically, the control unit 82 drives the head moving mechanism 24 to move the liquid ejection head 200 along the main scanning direction X and ejects ink from the liquid ejection head 200, and drives the transport mechanism 22. The printing on the medium 12 is executed by alternately repeating the control of transporting the medium 12 in the sub-scanning direction Y.

The ejection control unit 83 drives the energy generation element 215 by outputting a control signal based on a predetermined drive waveform, and ejects ink from the nozzle 226. In the following description, the operation of ejecting ink from the nozzle 226 by the ejection control unit 83 is also referred to as a “liquid ejection operation”. The liquid discharge operation is performed during the printing operation of the liquid discharge device 100.

The air introduction control unit 84 executes the air introduction control process described later to introduce air into the energy generation chamber 213. In the present embodiment, the air introduction control unit 84 controls the pressures of the pressure generating mechanisms P1 and P2 of the circulation mechanism 250 to generate a negative pressure in the energy generating chamber 213, thereby causing the nozzle 226 into the energy generating chamber 213. Pull in air. Specifically, the air introduction control unit 84 transmits a control signal for generating a negative pressure to the energy generation chamber 213. Therefore, in the present embodiment, the air introduction control unit 84 introduces air into the energy generation chamber 213 without driving the energy generation element 215. In the following description, the operation of introducing air into the energy generation chamber 213 by the air introduction control unit 84 is also referred to as an “air introduction operation”. The air introduction operation is executed when the liquid discharge operation by the discharge control unit 83 is not executed.

The input / output interface 91 is connected to a transfer mechanism 22, a head moving mechanism 24, a liquid discharge head 200, an operation panel (not shown) provided on the liquid discharge device 100, or the like via control signal lines. Various settings input by the user to the operation panel are input to the CPU 81 via the input / output interface 91. A control signal is output to the transport mechanism 22, the head moving mechanism 24, and the liquid discharge head 200 via the input / output interface 91 based on the instruction of the CPU 81.

The memory 95 includes a ROM, RAM and EEPROM. The memory 95 stores in advance a control program that realizes the functions of the above-mentioned function units and various setting values.

A2. Liquid discharge operation processing:
FIG. 6 is a flowchart showing a processing procedure of the liquid discharge operation processing. The liquid discharge operation process is started when, for example, the user gives an instruction to turn off the power of the liquid discharge device 100 using an operation panel or the like (not shown).

In step S10, the discharge control unit 83 generates a positive pressure by the first pressure generation mechanism P1. In step S15, the discharge control unit 83 generates a negative pressure by the second pressure generation mechanism P2. In steps S10 and S15, the circulation of ink between the energy generation chamber 213 and the liquid storage unit 14 is started. In the state where the circulation is performed, the energy generation element 215 is driven to execute the liquid discharge operation from the nozzle 226.

In step S20, the discharge control unit 83 determines whether or not the end flag is on. The end flag in the liquid discharge operation process is a flag indicating that the liquid discharge operation to the medium 12 has been completed, and the initial value is set to off and is set to on when the liquid discharge operation ends.

In step S20 described above, when the discharge control unit 83 determines that the end flag is not on (step S20: NO), the discharge control unit 83 repeatedly executes the step S20 described above until it determines that the end flag is on. On the other hand, when it is determined that the end flag is on (step S20: YES), the discharge control unit 83 stops the first pressure generating mechanism P1 in step S25 and stops the second pressure generating mechanism P2 in step S30. .. After the execution of step S30, the liquid discharge operation process ends.

A3. Air introduction control process:
FIG. 7 is a flowchart showing a processing procedure of the air introduction control process. The air introduction control process is started when, for example, the user gives an instruction to turn off the power of the liquid discharge device 100 using an operation panel or the like (not shown).

In step S105, the air introduction control unit 84 stops the operation of the first pressure generating mechanism P1. In step S110, the air introduction control unit 84 generates a negative pressure larger than that during the liquid discharge operation by the second pressure generation mechanism P2. Specifically, the air introduction control unit 84 sets the target pressure of the second pressure generation mechanism P2 to a pressure larger than the pressure at the time of executing the liquid discharge operation, and transmits a control signal to the second pressure generation mechanism P2. To do. Along with this, a negative pressure is generated in the liquid discharge head 200. As a result, air is drawn into the energy generation chamber 213 from the nozzle 226, and the ink existing in the liquid discharge head 200 flows into the recovery flow path 253.

In step S115, the air introduction control unit 84 determines whether or not the end flag is on. The end flag in the air introduction control process is a flag indicating that a predetermined amount of air has been introduced into the energy generation chamber 213, and the initial value is set to off. The end flag is changed to on, for example, after a predetermined time has elapsed from the execution of step S110. The condition for changing the end flag to ON can be arbitrarily determined based on the volume of the energy generation chamber 213, the target pressure of the second pressure generation mechanism P2 in step S110, and the like.

In step S115 described above, when the air introduction control unit 84 determines that the end flag is not on (step S115: NO), the air introduction control unit 84 repeatedly executes the step S115 described above until it determines that the end flag is on. On the other hand, when it is determined that the end flag is on (step S115: YES), in step S120, the air introduction control unit 84 stops the operation of the second pressure generation mechanism P2. After the execution of step S120, the air introduction control process ends.

According to the liquid discharge device 100 of the first embodiment described above, when the liquid discharge operation is not executed, the air introduction operation for introducing air into the energy generation chamber 213 without driving the energy generation element 215 is executed. Therefore, air can be filled in the energy generation chamber 213. Therefore, it is possible to prevent the energy generation chamber 213 from being left filled with ink. Therefore, it is possible to prevent damage to the energy generation chamber 213 in a low temperature environment such as below freezing.

The second pressure generation mechanism P2 applies a negative pressure to the energy generation chamber 213 to execute a liquid discharge operation, and the second pressure generation mechanism P2 applies a negative pressure to the energy generation chamber 213 to a larger negative pressure than the liquid discharge operation to introduce air. Since the operation is executed, both the liquid discharge operation and the air introduction operation can be executed by controlling the second pressure generation mechanism P2. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

By controlling the operation of the second pressure generation mechanism P2, ink is circulated between the energy generation chamber 213 and the liquid storage unit 14, and the second pressure generation mechanism P2 applies a negative pressure to the energy generation chamber 213. By controlling the two pressure generating mechanism P2, both the circulation of ink in the circulation mechanism 250 and the application of negative pressure to the energy generation chamber 213 can be realized. Therefore, it is possible to prevent the circulation mechanism 250 from becoming complicated in controlling the circulation of ink and the application of negative pressure to the energy generation chamber 213. By applying a negative pressure to the energy generation chamber 213, air can be introduced into the energy generation chamber 213, so that it is possible to prevent the energy generation chamber 213 from being left filled with ink. Therefore, it is possible to prevent damage to the energy generation chamber 213 in a low temperature environment such as below freezing.

As described above, according to the present embodiment, damage to the energy generation chamber 213 can be suppressed even in a low temperature environment by performing the air introduction operation. Further, according to the present embodiment, since the air introduction operation is realized without driving the energy generation element 215, the power consumption is smaller than that of the configuration in which the air introduction operation is realized by driving the energy generation element 215. A large amount of air can be introduced into the energy generation chamber 213. Further, according to the present embodiment, since the air introduction operation is executed when the liquid discharge operation is not executed, the configuration for executing the air introduction operation when the liquid discharge operation is executed, that is, the nozzle 226 Ink consumption can be suppressed as compared with a configuration in which air is drawn from the nozzle 226 into the energy generation chamber 213 by ejecting ink from the nozzle 226.

B. Second embodiment:
Since the liquid discharge device in the second embodiment is the same as the liquid discharge device 100 in the first embodiment, detailed description thereof will be omitted.

FIG. 8 is a flowchart showing a processing procedure of the air introduction control processing in the second embodiment. The air introduction control process of the second embodiment shows the air introduction control process of the first embodiment shown in FIG. 7 at the point where steps S110 and S120 are omitted and the point where steps S205 and S210 are additionally executed. Is different. Since step S215 in the second embodiment is the same as step S115 in the first embodiment and step S220 in the second embodiment is the same as step S105 in the first embodiment, detailed description thereof will be omitted. ..

In the air introduction control process of the second embodiment, a negative pressure is generated in the liquid discharge head 200 by generating a negative pressure in the first pressure generating mechanism P1 instead of the second pressure generating mechanism P2, and energy is generated. Air is introduced into the generation chamber 213. Specifically, as shown in FIG. 8, when the air introduction control process is started, the air introduction control unit 84 stops the operation of the second pressure generation mechanism P2 in step S205. In step S210, the air introduction control unit 84 generates a negative pressure by the first pressure generation mechanism P1. Specifically, the air introduction control unit 84 changes the target pressure of the first pressure generating mechanism P1 from a positive pressure to a negative pressure, and transmits a control signal to the first pressure generating mechanism P1. Along with this, a negative pressure is generated in the liquid discharge head 200. As a result, air is drawn into the energy generation chamber 213 from the nozzle 226, and the ink existing in the liquid discharge head 200 flows into the recovery flow path 253. After the execution of step S210, step S215 is executed.

In step S215, when the air introduction control unit 84 determines that the end flag is ON (step S115: YES), in step S220, the operation of the first pressure generating mechanism P1 is stopped. After the execution of step S220, the air introduction control process ends.

According to the liquid discharge device of the second embodiment described above, the first pressure generation mechanism P1 applies a positive pressure to the energy generation chamber 213 to execute the liquid discharge operation, and the first pressure generation mechanism P1 performs the energy generation chamber 213. Since the air introduction operation is executed by applying a negative pressure to the liquid, both the liquid discharge operation and the air introduction operation can be executed by controlling the pressure of the first pressure generating mechanism P1. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

C. Third Embodiment:
Since the liquid discharge device in the third embodiment is the same as the liquid discharge device 100 in the first embodiment, detailed description thereof will be omitted.

FIG. 9 is a flowchart showing a processing procedure of the air introduction control processing in the third embodiment. The air introduction control process of the third embodiment is composed of a combination of the air introduction control process of the first embodiment shown in FIG. 7 and the air introduction control process of the second embodiment shown in FIG. Step S305 of the third embodiment is the same as step S210 of the second embodiment. Step S310 of the third embodiment is the same as step S110 of the first embodiment. Step S315 of the third embodiment is the same as step S115 of the first embodiment. Step S320 of the third embodiment is the same as step S105 of the first embodiment. Step S325 of the third embodiment is the same as step S120 of the first embodiment.

In the air introduction control process of the third embodiment, a negative pressure is generated in the liquid discharge head 200 by generating a negative pressure by both the pressure generating mechanisms of the first pressure generating mechanism P1 and the second pressure generating mechanism P2. Then, air is introduced into the energy generation chamber 213. Specifically, as shown in FIG. 9, when the air introduction control process is started, the air introduction control unit 84 generates a negative pressure by the first pressure generation mechanism P1 in step S305, and the second in step S310. The pressure generation mechanism P2 generates a larger negative pressure than during the liquid discharge operation. In addition, step S305 and step S310 may be executed in any order, or may be executed at the same time. After the execution of step S310, step S315 is executed.

When the air introduction control unit 84 determines in step S315 that the end flag is ON (step S315: YES), the operation of the first pressure generating mechanism P1 is stopped in step S320, and the second pressure is generated in step S325. The operation of the mechanism P2 is stopped. In addition, step S320 and step S325 may be executed in any order, or may be executed at the same time. After the execution of step S325, the air introduction control process ends.

According to the liquid discharge device of the third embodiment described above, the air introduction operation is performed by applying a negative pressure to the energy generation chamber 213 by the pressure generation mechanisms of both the first pressure generation mechanism P1 and the second pressure generation mechanism P2. Therefore, the air introduction operation can be executed without significantly changing the control of the first pressure generation mechanism P1 and the second pressure generation mechanism P2 from the time of the liquid discharge operation. Therefore, it is possible to prevent the control itself of the air introduction operation from becoming complicated.

D. Fourth Embodiment:
FIG. 10 is an explanatory diagram schematically showing a schematic configuration of a circulation mechanism 250a included in the liquid discharge device according to the fourth embodiment. The difference between the liquid discharge device of the fourth embodiment and the liquid discharge device 100 of the first embodiment is that the circulation mechanism 250a is provided instead of the circulation mechanism 250. The circulation mechanism 250a is different from the circulation mechanism 250 of the first embodiment in that the air introduction flow path 255, the air introduction flow path valve 263, the third pressure generation mechanism P3, and the circulation flow path valve 261 are additionally provided. The same components as those of the circulation mechanism 250 of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The air introduction flow path 255 communicates with the supply flow path 251 and takes in air from the outside air and supplies it to the supply flow path 251. The air introduction flow path 255 is connected to the supply flow path 251 on the upstream side of the first pressure generation mechanism P1. The air introduction flow path valve 263 and the third pressure generation mechanism P3 are arranged in the air introduction flow path 255 toward the supply flow path 251 in this order. The air introduction flow path valve 263 opens and closes in response to a control signal from the air introduction control unit 84 to control the inflow of air into the supply flow path 251. In the present embodiment, the air introduction flow path valve 263 is closed during the liquid discharge operation. The third pressure generation mechanism P3 operates in response to the control signal of the air introduction control unit 84, and sends the air in the air introduction flow path 255 to the liquid discharge head 200.

The circulation flow path valve 261 is provided in the supply flow path 251 on the upstream side of the connection position with the air introduction flow path 255. The circulation flow path valve 261 opens and closes in response to a control signal from the air introduction control unit 84 to control the inflow of ink to the downstream side of the supply flow path 251.

FIG. 11 is a flowchart showing a processing procedure of the air introduction control processing in the fourth embodiment. The air introduction control process of the fourth embodiment omits step S105, step S110 and step S120, and additionally executes step S405, step S410, step S415, step S425, step S430 and step S435. Is different from the air introduction control process of the first embodiment shown in FIG. Since step S420 in the fourth embodiment is the same as step S115 in the first embodiment, detailed description thereof will be omitted.

In the air introduction control process of the fourth embodiment, air is taken into the supply flow path 251 by opening the air introduction flow path valve 263, and the taken-in air is introduced into the energy generation chamber 213. Specifically, as shown in FIG. 11, when the air introduction control process is started, the air introduction control unit 84 closes the circulation flow path valve 261 in step S405. As a result, in the supply flow path 251, ink is not supplied to the downstream side of the circulation flow path valve 261. In step S410, the air introduction control unit 84 opens the air introduction flow path valve 263. In step S415, the air introduction control unit 84 generates a positive pressure by the third pressure generation mechanism P3. Specifically, the air introduction control unit 84 changes the target pressure of the third pressure generation mechanism P3 to a positive pressure, and transmits a control signal to the third pressure generation mechanism P3. As a result, the air in the supply flow path 251 flows into the liquid discharge head 200. After the execution of step S415, step S420 is executed.

In step S420, when the air introduction control unit 84 determines that the end flag is ON (step S420: YES), in step S425, the operation of the third pressure generating mechanism P3 is stopped. In step S430, the air introduction control unit 84 closes the air introduction flow path valve 263. In step S435, the air introduction control unit 84 opens the circulation flow path valve 261. After the execution of step S435, the air introduction control process ends.

According to the liquid discharge device of the fourth embodiment described above, the air introduction flow path valve 263 is closed as the liquid discharge operation, and the air introduction flow path valve 263 is opened as the air introduction operation. By controlling the opening and closing of the valve 263, both the liquid discharge operation and the air introduction operation can be executed. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

An air introduction flow path 255 for introducing air into the supply flow path 251 is provided, and by controlling the operation of the first pressure generation mechanism P1 and the second pressure generation mechanism P2, between the energy generation chamber 213 and the liquid storage unit 14. In the circulation mechanism 250a, both the circulation of the ink and the introduction of air into the supply flow path 251 can be realized in the circulation mechanism 250a. Therefore, since the air introduced into the supply flow path 251 can flow into the energy generation chamber 213, it is possible to prevent the energy generation chamber 213 from being left with the ink filled. Therefore, it is possible to prevent damage to the energy generation chamber 213 in a low temperature environment such as below freezing.

E. Fifth embodiment:
FIG. 12 is an explanatory diagram schematically showing a schematic configuration of a circulation mechanism 250b included in the liquid discharge device according to the fifth embodiment. The difference between the liquid discharge device of the fifth embodiment and the liquid discharge device of the fourth embodiment is that the circulation mechanism 250b is provided instead of the circulation mechanism 250a. The circulation mechanism 250b is different from the circulation mechanism 250a of the fourth embodiment in that the circulation flow path valve 261 is omitted and the connection position between the supply flow path 251 and the air introduction flow path 255. The same components as those of the circulation mechanism 250a of the fourth embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The air introduction flow path 255 is connected to the supply flow path 251 on the downstream side of the first pressure generation mechanism P1. In other words, the air introduction flow path 255 is connected to the supply flow path 251 at a position between the first pressure generation mechanism P1 and the liquid discharge head 200.

FIG. 13 is a flowchart showing a processing procedure of the air introduction control processing in the fifth embodiment. The air introduction control process of the fifth embodiment is different from the air introduction control process of the fourth embodiment shown in FIG. 11 in that step S403 is additionally executed and steps S405 and S435 are omitted. .. Since the other procedures of the air introduction control process of the fifth embodiment are the same as those of the fourth embodiment, the same procedures are designated by the same reference numerals and detailed description thereof will be omitted. Since step S403 of the fifth embodiment is the same as step S105 of the first embodiment shown in FIG. 7, detailed description thereof will be omitted.

In the air introduction control process of the fifth embodiment, the first pressure generation mechanism P1 is used instead of the circulation flow path valve 261 to stop the supply of ink to the downstream side of the supply flow path 251. Specifically, as shown in FIG. 13, when the air introduction control process is started, the air introduction control unit 84 stops the operation of the first pressure generation mechanism P1 in step S403. As a result, in the supply flow path 251, ink is not supplied to the downstream side of the first pressure generating mechanism P1. After the execution of step S403, the above-mentioned step S410 is executed.

According to the liquid discharge device of the fifth embodiment described above, the air introduction flow path 255 is connected to the supply flow path 251 at a position between the first pressure generation mechanism P1 and the energy generation chamber 213, and thus air. The air supplied to the introduction flow path 255 can be supplied to the supply flow path 251 without passing through the first pressure generation mechanism P1. Therefore, the required amount of air can be accurately supplied to the supply flow path 251.

F. Sixth Embodiment:
FIG. 14 is an explanatory diagram schematically showing a schematic configuration of a circulation mechanism 250c included in the liquid discharge device according to the sixth embodiment. The difference between the liquid discharge device of the sixth embodiment and the liquid discharge device of the fifth embodiment is that the circulation mechanism 250c is provided instead of the circulation mechanism 250b. The circulation mechanism 250c is different from the circulation mechanism 250b of the fifth embodiment in that the connection flow path 257 is additionally provided. The same components as those of the circulation mechanism 250b of the fifth embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The connection flow path 257 guides a part of the ink supplied from the supply flow path 251 to the recovery flow path 253. The connection flow path 257 is located between the position PS1 between the first pressure generation mechanism P1 and the liquid discharge head 200 in the supply flow path 251 and between the second pressure generation mechanism P2 and the liquid discharge head 200 in the recovery flow path 253. The position PS2 is connected. A three-way valve (not shown) is provided at the position PS1 which is a connection portion of the supply flow path 251 with the connection flow path 257. The three-way valve is supplied to the flow rate of the ink supplied to the liquid discharge head 200 and the connection flow path 257 among the inks flowing through the supply flow path 251 in response to the control signal from the control unit 80. Adjust the ink flow rate.

The air introduction control process in the sixth embodiment is the same as the air introduction control process in the fifth embodiment shown in FIG.

According to the liquid discharge device of the sixth embodiment described above, the air introduction flow path 255 is a supply flow at a position between the connection position PS1 with the connection flow path 257 in the supply flow path 251 and the energy generation chamber 213. Since it is connected to the road 251 it is possible to prevent the air supplied to the air introduction flow path 255 from flowing into the connection flow path 257. Therefore, the required amount of air can be accurately supplied to the supply flow path 251.

G. Seventh Embodiment:
FIG. 15 is an explanatory diagram schematically showing a schematic configuration of a control unit 80a included in the liquid discharge device according to the seventh embodiment. The difference between the liquid discharge device of the seventh embodiment and the liquid discharge device 100 of the first embodiment is that the control unit 80a is provided instead of the control unit 80. The control unit 80a is different from the control unit 80 of the first embodiment in that the CPU 81a is provided in place of the CPU 81 and the memory 95a is provided in place of the memory 95. The CPU 81a differs from the CPU 81 in that it functions as an air introduction control unit 84a instead of the air introduction control unit 84. The memory 95a is different from the memory 95 in that a drive waveform 96 is additionally provided. The same components as those of the control unit 80 of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The air introduction control unit 84a executes the air introduction operation by outputting a control signal based on a predetermined drive waveform to drive the energy generation element 215. Specifically, the air introduction control unit 84a applies a predetermined drive pulse to the energy generation element 215 to cause a pressure change in the energy generation chamber 213 to generate the meniscus of the nozzle 226 in the energy generation chamber. It vibrates greatly toward the 213 side. At this time, air is drawn from the outside air into the energy generation chamber 213 together with the meniscus of the nozzle 226.

In the present embodiment, the "predetermined drive pulse" means a second pulse different from the first pulse, which is a drive pulse during the liquid discharge operation. The second pulse is set to a potential at which the meniscus in the nozzle 226 can be drawn more into the energy generation chamber 213 as compared with the first pulse. The first pulse and the second pulse can be calculated by experiments or the like, and are stored in the memory 95a as the drive waveform 96.

According to the liquid discharge device of the seventh embodiment described above, the first pulse is applied to the energy generation element 215 as the liquid discharge operation, and the second pulse different from the first pulse is applied to the energy generation element 215 as the air introduction operation. Since the energy is applied, both the liquid discharge operation and the air introduction operation can be executed by controlling the pulse applied to the energy generation element 215. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

H. Other embodiments:
(1) In the first to sixth embodiments, the circulation mechanisms 250, 250a, 250b and 250c do not have to include the second pressure generating mechanism P2. In this case, the air introduction control unit 84 generates a negative pressure in the liquid discharge head 200 by utilizing the head difference between the first pressure generation mechanism P1 and the recovery flow path 253, and air in the energy generation chamber 213. May be introduced. Specifically, in the circulation mechanism, the head difference is generated by arranging the first pressure generating mechanism P1 at a position lower than the recovery flow path 253. When the ink in the supply flow path 251 is sucked by the liquid discharge head 200, the supply flow path 251 becomes equal to or higher than a predetermined negative pressure. When the supply flow path 251 becomes equal to or higher than a predetermined negative pressure, the ink of the liquid storage unit 14 is supplied to the supply flow path 251. At this time, the ink in the energy generation chamber 213 is drawn into the recovery flow path 253, and air is introduced into the energy generation chamber 213 via the nozzle 226. Therefore, even in such a configuration, the same effect as that of the first to sixth embodiments is obtained.

(2) In each of the above embodiments, the air introduction control units 84 and 84a may execute the air introduction operation only when the temperature of the ink in the energy generation chamber 213 is lower than the predetermined temperature. Specifically, the liquid discharge head 200 is provided with a detection unit that detects the temperature of the ink in the energy generation chamber 213, and when the temperature detected by the detection unit is the first temperature, the air introduction control process is performed. If the temperature detected by the detection unit is a second temperature lower than the first temperature, the air introduction control process may be executed. The first temperature may be, for example, 0 ° C., and the second temperature may be, for example, −10 ° C. As the first temperature and the second temperature, any other temperature can be adopted as long as the ink can freeze. Further, the first temperature and the second temperature may be set based on the climate of the environment in which the liquid ejection devices 100 and 100a are used, the viscosity of the ink, and the like. Further, the detection unit may be configured to detect the temperature of the ink in the recovery flow path 253 and estimate the temperature of the ink in the energy generation chamber 213 using such temperature. According to such a configuration, when the detected temperature is the first temperature, the air introduction operation is not executed, and when the detected temperature is the second temperature lower than the first temperature, the air is introduced. Since the operation is not executed, the processing load due to the execution of the air introduction operation can be reduced.

(3) In the seventh embodiment, when the air introduction control process is executed in a short period such as between printing jobs, the air introduction control process is executed by the air introduction control unit 84a, and when the power of the liquid discharge device 100 is turned off, etc. When the air introduction control process is executed before the long-term pause, the air introduction control process by the air introduction control unit 84 may be executed. Further, the air introduction control unit 84 is the first air introduction control unit, the air introduction operation by the air introduction control unit 84 is the first air introduction operation, and the air introduction control unit 84a is the second air introduction control unit and the air introduction control unit 84a. When the air introduction operation is set to the second air introduction operation, the amount of air introduced may be different between the first air introduction operation and the second air introduction operation. For example, the amount of air introduced in the first air introduction operation may be larger than the amount of air introduced in the second air introduction operation. By doing so, more air can be introduced into the energy generation chamber 213 in the second air introduction operation as compared with the configuration in which the first air introduction operation is executed.

(4) In the fourth to sixth embodiments, the third pressure generating mechanism P3 may be omitted. In this case, the air taken in through the air introduction flow path 255 may be supplied to the liquid discharge head 200 by using the first pressure generation mechanism P1. Even in such a configuration, the same effect as that of the fourth to sixth embodiments is obtained.

(5) In each of the above embodiments, the liquid discharge device 100 is a serial printer in which the liquid discharge head 200 is conveyed in the X direction, but the liquid discharge head 200 is fixed and the nozzle 226 extends over the entire width of the medium 12. Line printers arranged side by side may be used. Even in such a configuration, the same effect as that of each of the above-described embodiments can be obtained.

(6) In each of the above embodiments, the liquid discharged from the nozzle 226 may be a liquid other than ink. For example
(1) Color material used for manufacturing color filters for image display devices such as liquid crystal displays (2) Used for forming electrodes for organic EL (Electro Luminescence) displays and surface emission displays (Field Emission Display, FED) Electrode material (3) Liquid containing bioorganic substances used for biochip production (4) Sample as precision pipette (5) Lubricating oil (6) Resin liquid (7) Micro hemispherical lens (optical lens) used for optical communication elements, etc. ), Etc., a transparent resin liquid such as an ultraviolet curable resin liquid (8) A liquid that ejects an acidic or alkaline etching liquid to etch a substrate, etc. (9) Any other minute amount of droplets. You may.

The term "droplet" refers to the state of the liquid discharged from the liquid discharge device 100, and includes those having a granular, tear-like, or thread-like tail. Further, the “liquid” referred to here may be any material that can be consumed by the liquid discharge device 100. For example, the "liquid" may be a material in a liquid state when the substance is in a liquid phase, a material in a liquid state with high or low viscosity, and a sol, gel water, other inorganic solvent, organic solvent, solution, etc. Liquid materials such as liquid resins and liquid metals (metal melts) are also included in "liquid". Further, not only a liquid as a state of a substance but also a liquid in which particles of a functional material made of a solid substance such as a pigment or a metal particle are dissolved, dispersed or mixed in a solvent are included in the "liquid". Typical examples of liquids include ink and liquid crystal. Here, the ink includes general water-based inks, oil-based inks, and various liquid compositions such as gel inks and hot melt inks. Even in these configurations, the same effect as in each embodiment is obtained.

In each of the above embodiments, a part of the configuration realized by the hardware may be replaced with software, and conversely, a part of the configuration realized by the software may be replaced with hardware. .. In addition, when a part or all of the functions of the present disclosure are realized by software, the software (computer program) can be provided in a form stored in a computer-readable recording medium. In the present disclosure, the "computer-readable recording medium" is not limited to a portable recording medium such as a flexible disk or a CD-ROM, but is an internal storage device in a computer such as various RAMs or ROMs, a hard disk, or the like. It also includes an external storage device that is fixed to your computer. That is, the term "computer-readable recording medium" has a broad meaning including any recording medium on which data can be fixed rather than temporarily.

The present disclosure is not limited to the above-described embodiment, and can be realized by various configurations within a range not deviating from the gist thereof. For example, the technical features in the embodiments corresponding to the technical features in each form described in the column of the outline of the invention may be used to solve some or all of the above-mentioned problems, or one of the above-mentioned effects. It is possible to replace or combine as appropriate to achieve a part or all. Further, if the technical feature is not described as essential in the present specification, it can be appropriately deleted.

I. Other forms:
(1) According to one embodiment of the present disclosure, a liquid discharge device is provided. This liquid discharge device is provided in a nozzle for discharging a liquid, an energy generation chamber communicating with the nozzle, and the energy generation chamber, and is an energy generation element for generating energy for discharging the liquid from the nozzle. A circulation mechanism for circulating the liquid between the energy generation chamber and the outside of the energy generation chamber, and a discharge operation for driving the energy generation element to discharge the liquid from the nozzle. It includes a control unit and an air introduction control unit that executes an air introduction operation for introducing air into the energy generation chamber without driving the energy generation element.

According to this form of the liquid discharge device, since the air introduction operation for introducing air into the energy generation chamber is executed without driving the energy generation element, the energy generation chamber can be filled with air by an operation different from the liquid discharge operation. .. Therefore, it is possible to prevent the energy generation chamber from being left filled with the liquid. Therefore, it is possible to prevent damage to the energy generation chamber in a low temperature environment such as below freezing.

(2) In the liquid discharge device of the above embodiment, the circulation mechanism is provided in a supply flow path that communicates the energy generation chamber with the outside and supplies the liquid to the energy generation chamber, and in the supply flow path. A first pressure generation mechanism, a recovery flow path that communicates the energy generation chamber with the outside and recovers the liquid from the energy generation chamber, and a second pressure generation mechanism provided in the recovery flow path. The liquid may be circulated by controlling the operation of at least one of the first pressure generating mechanism and the second pressure generating mechanism.
According to the liquid discharge device of this form, the liquid is circulated in the circulation mechanism by controlling the operation of at least one of the first pressure generating mechanism and the second pressure generating mechanism, so that the liquid is circulated by a simple configuration. Can be made to.

(3) In the liquid discharge device of the above embodiment, the air introduction control unit applies a negative pressure to the energy generation chamber by at least one of the first pressure generating mechanism and the second pressure generating mechanism. The air introduction operation may be performed.
According to the liquid discharge device of this form, the air introduction operation is executed by applying a negative pressure to the energy generation chamber by at least one of the first pressure generating mechanism and the second pressure generating mechanism, so that the first pressure The air introduction operation can be executed without significantly changing the control of the generation mechanism and the second pressure generation mechanism from the time of the liquid discharge operation. Therefore, it is possible to prevent the control itself of the air introduction operation from becoming complicated.

(4) In the liquid discharge device of the above embodiment, the discharge control unit applies a positive pressure to the energy generation chamber by the first pressure generation mechanism to execute the liquid discharge operation, and the air introduction control unit performs the liquid discharge operation. The air introduction operation may be executed by applying a negative pressure to the energy generation chamber by the first pressure generation mechanism.
According to the liquid discharge device of this form, the first pressure generation mechanism applies a positive pressure to the energy generation chamber to execute the liquid discharge operation, and the first pressure generation mechanism applies a negative pressure to the energy generation chamber to introduce air. Since the operation is executed, both the liquid discharge operation and the air introduction operation can be executed by controlling the pressure of the first pressure generating mechanism. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

(5) In the liquid discharge device of the above embodiment, the discharge control unit applies a negative pressure to the energy generation chamber by the second pressure generation mechanism to execute the liquid discharge operation, and the air introduction control unit performs the liquid discharge operation. The air introduction operation may be executed by applying a negative pressure larger than the liquid discharge operation to the energy generation chamber by the second pressure generation mechanism.
According to the liquid discharge device of this form, a negative pressure is applied to the energy generation chamber by the second pressure generation mechanism to execute the liquid discharge operation, and the second pressure generation mechanism causes the energy generation chamber to have a larger negative pressure than the liquid discharge operation. Since the air introduction operation is executed by giving, both the liquid discharge operation and the air introduction operation can be executed by controlling the second pressure generation mechanism. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

(6) In the liquid discharge device of the above embodiment, the circulation mechanism is further provided in the air introduction flow path which is connected to the supply flow path and introduces air into the supply flow path, and the air introduction flow path. The discharge control unit may close the valve in the liquid discharge operation, and the air introduction control unit may open the valve in the air introduction operation.
According to this type of liquid discharge device, the valve provided in the air introduction flow path is closed in the liquid discharge operation, and the valve provided in the air introduction flow path is opened in the air introduction operation, so that the valve is opened and closed. By controlling the above, both the liquid discharge operation and the air introduction operation can be executed. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

(7) In the liquid discharge device of the above embodiment, the air introduction flow path may be connected to the supply flow path at a position between the first pressure generation mechanism and the energy generation chamber.
According to the liquid discharge device of this form, the air introduction flow path is connected to the supply flow path at the position between the first pressure generation mechanism and the energy generation chamber, so that the air supplied to the air introduction flow path can be supplied. It can be supplied to the supply flow path without going through the first pressure generation mechanism. Therefore, the required amount of air can be accurately supplied to the supply flow path.

(8) In the liquid discharge device of the above-described embodiment, the circulation mechanism is further located between the position between the first pressure generating mechanism and the energy generating chamber and between the second pressure generating mechanism and the energy generating chamber. The air introduction flow path is provided at a position between the connection position with the connection flow path in the supply flow path and the energy generation chamber, and the supply flow path is provided. It may be connected to the flow path.
According to the liquid discharge device of this form, the air introduction flow path is connected to the supply flow path at the position between the connection position with the connection flow path and the energy generation chamber in the supply flow path, so that the air introduction flow path is connected. It is possible to prevent the air supplied to the water from flowing into the connection flow path. Therefore, the required amount of air can be accurately supplied to the supply flow path.

(9) In the liquid discharge device of the above embodiment, the air introduction control unit is the first air introduction control unit, the air introduction operation is the first air introduction operation, and the air introduction operation in the first air introduction operation is A second air introduction control unit that executes a second air introduction operation for introducing air into the energy generation chamber by different operations is further provided, and the amount of air introduced in the first air introduction operation is the second air introduction operation. It may be more than the amount of air introduced in.
According to the liquid discharge device of this form, the amount of air introduced in the first air introduction operation is larger than the amount of air introduced in the second air introduction operation, so that the amount of air introduced in the first air introduction operation is larger than the amount of air introduced in the first air introduction operation. More air can be introduced into the energy generation chamber in the second air introduction operation.

(10) In the liquid discharge device of the above embodiment, the discharge control unit applies a first pulse to the energy generating element as the liquid discharge operation, and the second air introduction control unit performs the second air introduction operation. As a result, a second pulse different from the first pulse may be applied to the energy generating element.
According to the liquid discharge device of this form, a first pulse is applied to the energy generation element as a liquid discharge operation, and a second pulse different from the first pulse is applied to the energy generation element as a second air introduction operation. Therefore, by controlling the pulse applied to the energy generating element, both the liquid discharge operation and the air introduction operation can be executed. Therefore, it is possible to prevent the control itself of the liquid discharge operation and the air introduction operation from becoming complicated.

(11) The liquid discharge device of the above embodiment further includes a detection unit that detects the temperature of the liquid in the energy generation chamber, and the air introduction control unit has the temperature detected by the detection unit as the first temperature. If this is the case, the air introduction operation may not be executed, and the air introduction operation may be executed when the temperature detected by the detection unit is a second temperature lower than the first temperature.
According to the liquid discharge device of this form, when the detected temperature is the first temperature, the air introduction operation is not executed, and when the detected temperature is the second temperature lower than the first temperature, the air introduction operation is not executed. Since the air introduction operation is not executed, the processing load due to the execution of the air introduction operation can be reduced.

(12) According to another embodiment of the present disclosure, a liquid discharge device is provided. This liquid discharge device is a circulation mechanism that connects a nozzle for discharging a liquid, an energy generation chamber communicating with the nozzle, and the outside of the energy generation chamber and the energy generation chamber to generate the energy. A recovery channel for supplying the liquid to the chamber, a first pressure generating mechanism provided in the supply channel, the energy generation chamber and the outside, and recovering the liquid from the energy generation chamber. The flow path and the second pressure generation mechanism provided in the recovery flow path are provided, and the operation of at least one of the first pressure generation mechanism and the second pressure generation mechanism is controlled. A control unit that applies negative pressure to the energy generation chamber by at least one of a circulation mechanism that circulates the liquid between the energy generation chamber and the outside, and the first pressure generation mechanism and the second pressure generation mechanism. And.

According to the liquid discharge device of this form, the liquid is circulated between the energy generation chamber and the outside by controlling the operation of at least one of the first pressure generating mechanism and the second pressure generating mechanism, and the first Since a negative pressure is applied to the energy generation chamber by at least one of the pressure generating mechanism and the second pressure generating mechanism, circulation is performed by controlling at least one of the first pressure generating mechanism and the second pressure generating mechanism. Both the circulation of the liquid in the mechanism and the application of negative pressure to the energy generation chamber can be realized. Therefore, it is possible to suppress the complicated control of the circulation of the liquid and the application of the negative pressure to the energy generation chamber in the circulation mechanism. By applying a negative pressure to the energy generation chamber, air can be introduced into the energy generation chamber, so that it is possible to prevent the energy generation chamber from being left filled with liquid. Therefore, it is possible to prevent damage to the energy generation chamber in a low temperature environment such as below freezing.

(13) According to another embodiment of the present disclosure, a liquid discharge device is provided. This liquid discharge device is a circulation mechanism that connects a nozzle for discharging a liquid, an energy generation chamber communicating with the nozzle, and the outside of the energy generation chamber and the energy generation chamber to generate the energy. A recovery channel for supplying the liquid to the chamber, a first pressure generating mechanism provided in the supply channel, the energy generation chamber and the outside, and recovering the liquid from the energy generation chamber. A circulation mechanism including a flow path, a second pressure generating mechanism provided in the recovery flow path, an air introduction flow path connected to the supply flow path and introducing air into the supply flow path, and the first. A control unit for circulating the liquid between the energy generation chamber and the outside is provided by controlling the operation of at least one of the pressure generation mechanism and the second pressure generation mechanism.

According to the liquid discharge device of this form, an air introduction flow path for introducing air into the supply flow path is provided, and the operation of at least one of the first pressure generation mechanism and the second pressure generation mechanism is controlled. Since the liquid is circulated between the energy generation chamber and the outside, it is possible to realize both the circulation of the liquid and the introduction of air into the supply flow path in the circulation mechanism. Therefore, since the air introduced into the supply flow path can flow into the energy generation chamber, it is possible to prevent the energy generation chamber from being left filled with the liquid. Therefore, it is possible to prevent damage to the pressure generating chamber in a low temperature environment such as below freezing point.

The present disclosure is not limited to the above-described form as a liquid discharge device, and can be realized as various forms such as a method for driving a liquid discharge device and a liquid discharge system.

12 ... Medium, 14 ... Liquid storage unit, 22 ... Conveyance mechanism, 23 ... Conveyance belt, 24 ... Head movement mechanism, 25 ... Carriage, 80, 80a ... Control unit, 81, 81a ... CPU, 82 ... Control unit, 83 ... Discharge control unit, 84, 84a ... Air introduction control unit, 91 ... Input / output interface, 93 ... Internal bus, 95, 95a ... Memory, 96 ... Drive waveform, 100 ... Liquid discharge device, 200 ... Liquid discharge head, 212 ... Flow Road board, 213 ... Energy generation chamber, 214 ... Energy generation chamber board, 215 ... Energy generation element, 216 ... Protective board, 217 ... Introduction flow path board, 218 ... Derivation flow path board, 219 ... Vibration plate, 220 ... Nozzle board , 221 ... 1st compliance board, 222 ... 2nd compliance board, 223 ... 1st inlet, 224 ... Introduction liquid chamber, 226 ... Nozzle, 226s ... Nozzle row, 227 ... 1st liquid chamber, 228 ... Individual communication passage, 229 ... Nozzle communication passage, 230 ... Individual communication passage, 231 ... First outlet, 233 ... Second liquid chamber, 234 ... First common liquid chamber, 235 ... Derivation liquid chamber, 236 ... Second common liquid chamber, 238 ... Storage empty Unit, 239 ... through port, 240 ... lead electrode, 250, 250a, 250b, 250c ... circulation mechanism, 251 ... supply flow path, 253 ... recovery flow path, 255 ... air introduction flow path, 257 ... connection flow path, 261 ... Circulation flow path valve, 263 ... Air introduction flow path valve, P1 ... First pressure generation mechanism, P2 ... Second pressure generation mechanism, P3 ... Third pressure generation mechanism, PS1, PS2 ... Connection position

Claims (14)

It is a liquid discharge device
A nozzle for discharging liquid and
An energy generation chamber that communicates with the nozzle,
An energy generating element provided in the energy generating chamber and generating energy for discharging the liquid from the nozzle.
A circulation mechanism for circulating the liquid between the energy generation chamber and the outside of the energy generation chamber.
A discharge control unit that drives the energy generating element to execute a liquid discharge operation for discharging the liquid from the nozzle.
An air introduction control unit that executes an air introduction operation for introducing air into the energy generation chamber without driving the energy generation element.
To prepare
Liquid discharge device. The liquid discharge device according to claim 1.
The circulation mechanism
A supply flow path that communicates the energy generation chamber with the outside and supplies the liquid to the energy generation chamber.
The first pressure generating mechanism provided in the supply flow path and
A recovery flow path that communicates the energy generation chamber with the outside and recovers the liquid from the energy generation chamber.
A second pressure generating mechanism provided in the recovery flow path and
With
The circulation mechanism circulates the liquid by controlling the operation of at least one of the first pressure generating mechanism and the second pressure generating mechanism.
Liquid discharge device. The liquid discharge device according to claim 2.
The air introduction control unit executes the air introduction operation by applying a negative pressure to the energy generation chamber by at least one of the first pressure generation mechanism and the second pressure generation mechanism.
Liquid discharge device. The liquid discharge device according to claim 3.
The discharge control unit applies a positive pressure to the energy generation chamber by the first pressure generation mechanism to execute the liquid discharge operation.
The air introduction control unit executes the air introduction operation by applying a negative pressure to the energy generation chamber by the first pressure generation mechanism.
Liquid discharge device. The liquid discharge device according to claim 3 or 4.
The discharge control unit applies a negative pressure to the energy generation chamber by the second pressure generation mechanism to execute the liquid discharge operation.
The air introduction control unit executes the air introduction operation by applying a negative pressure larger than the liquid discharge operation to the energy generation chamber by the second pressure generation mechanism.
Liquid discharge device. The liquid discharge device according to claim 2.
The circulation mechanism further
An air introduction flow path that is connected to the supply flow path and introduces air into the supply flow path,
A valve provided in the air introduction flow path and
With
The discharge control unit closes the valve in the liquid discharge operation.
The air introduction control unit opens the valve in the air introduction operation.
Liquid discharge device. The liquid discharge device according to claim 6.
The air introduction flow path is connected to the supply flow path at a position between the first pressure generation mechanism and the energy generation chamber.
Liquid discharge device. The liquid discharge device according to claim 6.
The circulation mechanism further
A connection flow path connecting the position between the first pressure generation mechanism and the energy generation chamber and the position between the second pressure generation mechanism and the energy generation chamber is provided.
Prepare
The air introduction flow path is connected to the supply flow path at a position between the connection position of the supply flow path with the connection flow path and the energy generation chamber.
Liquid discharge device. The liquid discharge device according to any one of claims 1 to 8.
The air introduction control unit is set as the first air introduction control unit, and the air introduction operation is set as the first air introduction operation.
Further, a second air introduction control unit for executing a second air introduction operation for introducing air into the energy generation chamber by an operation different from the air introduction operation in the first air introduction operation is further provided.
The amount of air introduced in the first air introduction operation is larger than the amount of air introduced in the second air introduction operation.
Liquid discharge device. The liquid discharge device according to claim 9.
The discharge control unit applies a first pulse to the energy generating element as the liquid discharge operation.
As the second air introduction operation, the second air introduction control unit applies a second pulse different from the first pulse to the energy generating element.
Liquid discharge device. The liquid discharge device according to any one of claims 1 to 10.
A detection unit for detecting the temperature of the liquid in the energy generation chamber is further provided.
When the temperature detected by the detection unit is the first temperature, the air introduction control unit does not execute the air introduction operation, and the temperature detected by the detection unit is lower than the first temperature. When it is the second temperature, the air introduction operation is executed.
Liquid discharge device. It is a liquid discharge device
A nozzle for discharging liquid and
An energy generation chamber that communicates with the nozzle,
It is a circulation mechanism
A supply channel that communicates the energy generation chamber with the outside of the energy generation chamber and supplies the liquid to the energy generation chamber.
The first pressure generating mechanism provided in the supply flow path and
A recovery flow path that communicates the energy generation chamber with the outside and recovers the liquid from the energy generation chamber.
A second pressure generating mechanism provided in the recovery flow path and
A circulation mechanism for circulating the liquid between the energy generation chamber and the outside by controlling the operation of at least one of the first pressure generation mechanism and the second pressure generation mechanism.
A control unit that applies a negative pressure to the energy generation chamber by at least one of the first pressure generating mechanism and the second pressure generating mechanism.
To prepare
Liquid discharge device. It is a liquid discharge device
A nozzle for discharging liquid and
An energy generation chamber that communicates with the nozzle,
It is a circulation mechanism
A supply channel that communicates the energy generation chamber with the outside of the energy generation chamber and supplies the liquid to the energy generation chamber.
The first pressure generating mechanism provided in the supply flow path and
A recovery flow path that communicates the energy generation chamber with the outside and recovers the liquid from the energy generation chamber.
A second pressure generating mechanism provided in the recovery flow path and
An air introduction flow path that is connected to the supply flow path and introduces air into the supply flow path,
Circulation mechanism equipped with
A control unit that circulates the liquid between the energy generation chamber and the outside by controlling the operation of at least one of the first pressure generating mechanism and the second pressure generating mechanism.
To prepare
Liquid discharge device. The liquid is circulated between an energy generating element provided in an energy generation chamber communicating with a nozzle for discharging the liquid and generating energy for discharging the liquid from the nozzle and the outside of the energy generation chamber. It is a driving method of a liquid discharge device having a circulation mechanism for making the liquid discharge device.
A liquid discharge operation of driving the energy generating element to discharge the liquid from the nozzle is executed.
An air introduction operation for introducing air into the energy generation chamber without driving the energy generation element is executed.
Drive method.

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