JP2020203414A - Liquid jet device, control method for liquid jet device - Google Patents

Abstract

To provide a liquid jet device and a control method for a liquid jet device, allowing for reduction in variation of pressure necessary for supplying liquid.SOLUTION: The liquid jet device comprises: a liquid jet portion 41 which jets liquid: a holding portion 102 configured in such a way that a liquid supply source 101 is attached to and detached from the holding portion 102; a liquid supply flow passage 110 through which liquid is supplied from the liquid supply source 101 to the liquid jet portion 41; a supply mechanism 170 which pressurizes liquid in the liquid supply source 101 to supply pressure and supplies the pressurized liquid; a storage portion 120 which stores the liquid pressurized by the supply mechanism 170; a pressure mechanism 150 which makes pressure act on the liquid in the storage portion 120 from the outside; a liquid pressure adjustment mechanism 280 which is provided between the storage portion 120 and the liquid jet portion 41 in the liquid supply flow passage 110, and adjusts pressure of the liquid to be supplied to the liquid jet portion 41 to adjusted pressure lower than the supply pressure; and a control portion which when a residual amount RA of the liquid stored in the liquid supply source 101 becomes equal to a predetermined value VP, drives the pressure mechanism 150 to pressurize the liquid in the storage portion 120.SELECTED DRAWING: Figure 3

Description

The present invention relates to a liquid injection device such as a printer and a control method for the liquid injection device.

For example, as in Patent Document 1, there is a printer which is an example of a liquid injection device which ejects ink which is an example of a liquid and prints from a recording head which is an example of a liquid injection unit. The printer includes an ink supply path which is an example of a liquid supply flow path for supplying ink from an ink tank which is an example of a liquid supply source to a recording head. A sub-tank, which is an example of a storage unit, is provided in the ink supply path. The printer continued printing with the ink in the sub tank while the empty ink tank was replaced.

Japanese Unexamined Patent Publication No. 2005-96152

For example, when the liquid in the liquid supply source is pressurized and supplied to the liquid injection unit, the liquid in the storage unit may not be sufficiently pressurized. Therefore, when the liquid supply is switched from the liquid supply source to the storage unit, the pressure for supplying the liquid may fluctuate greatly.

The liquid injection device that solves the above problems includes a liquid injection unit that injects a liquid from a nozzle, a holding unit that is configured to attach and detach a liquid supply source that houses the liquid, and the liquid mounted on the holding unit. A liquid supply flow path configured to supply the liquid from the supply source to the liquid injection unit, and the liquid supply by pressurizing the liquid in the liquid supply source to a supply pressure so that the liquid can be injected from the nozzle. A supply mechanism configured to supply the liquid toward the liquid injection portion via the flow path, and a supply mechanism provided in the liquid supply flow path and configured to store the liquid pressurized by the supply mechanism. The liquid injection is provided between the storage unit, a pressure mechanism configured to apply pressure to the liquid in the storage unit from the outside, and the storage unit and the liquid injection unit in the liquid supply flow path. A hydraulic pressure adjusting mechanism that adjusts the pressure of the liquid supplied to the unit to an adjustment pressure that can be injected from the nozzle and is lower than the supply pressure, and the remaining amount of the liquid contained in the liquid supply source is a predetermined value. A control unit for driving the pressure mechanism to pressurize the liquid in the storage unit is provided.

A control method of a liquid injection device for solving the above problems is a liquid supply configured to supply the liquid from a liquid injection unit that injects the liquid from a nozzle and a liquid supply source that houses the liquid to the liquid injection unit. A supply configured to pressurize the flow path and the liquid in the liquid supply source so that the liquid can be ejected from the nozzle and supply the liquid to the liquid injection portion via the liquid supply flow path. A mechanism, a storage unit provided in the liquid supply flow path and configured to store the liquid pressurized by the supply mechanism, and a storage unit configured to apply pressure from the outside to the liquid in the storage unit. The pressure mechanism is provided between the storage unit and the liquid injection unit in the liquid supply flow path, and the pressure of the liquid supplied to the liquid injection unit can be injected from the nozzle and the supply pressure. A control method for a liquid injection device including a hydraulic pressure adjusting mechanism for adjusting to a lower adjusting pressure, and the pressure mechanism when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value. Pressurizes the liquid in the reservoir.

The perspective view which shows one Embodiment of the liquid injection apparatus. A side view schematically showing an internal configuration of a liquid injection device. The schematic diagram which shows the structure of the liquid injection device and the liquid supply device. Sectional drawing which shows the storage part and a pressure mechanism. FIG. 4 is a cross-sectional view taken along the line 5-5 in FIG. A flowchart showing a supply routine. A flowchart showing a print routine. The cross-sectional view which shows the modification example of the storage part. Sectional drawing which shows another modification example of a storage part.

Hereinafter, an embodiment of the liquid injection device and the control method of the liquid injection device will be described with reference to the drawings. The liquid injection device is, for example, an inkjet printer that prints images such as characters and photographs by injecting ink, which is an example of liquid, onto a medium such as paper.

As shown in FIG. 1, the liquid injection device 10 includes a pair of legs 11 and a housing 12 assembled on the legs 11. The liquid injection device 10 guides the medium M wound around the roll body to the feeding unit 13 for feeding out the medium M toward the inside of the housing 12, the guide unit 14 for guiding the medium M discharged from the housing 12, and the guide unit 14. A winding unit 15 for winding the medium M to be wound on a roll body is provided. The liquid injection device 10 includes a tension applying mechanism 16 for applying tension to the medium M wound around the winding unit 15, and an operation panel 17 operated by the user.

The liquid injection device 10 has a predetermined length as a width, a depth, and a height when it is installed at a place of use. Assuming that the liquid injection device 10 is installed on a horizontal plane, the direction of gravity is indicated by the Z axis. At this time, the width direction and the depth direction of the liquid injection device 10 are substantially horizontal. The depth direction of the liquid injection device 10 is indicated by the Y axis. The width direction of the liquid injection device 10 is indicated by an X axis that intersects the Y axis and the Z axis. Therefore, the X-axis, the Y-axis, and the Z-axis are coordinate axes indicating the width, depth, and height, respectively.

As shown in FIG. 2, the liquid injection device 10 includes a support base 20 for supporting the medium M and a transport unit 30 for transporting the medium M. The liquid injection device 10 includes a printing unit 40 that prints on the medium M, and a control unit 60 that controls the operation of the liquid injection device 10. The liquid injection device 10 includes a liquid supply device 100 that supplies a liquid to the printing unit 40. The control unit 60 includes, for example, a CPU, a memory, and the like. The control unit 60 controls the liquid injection device 10 and the liquid supply device 100 by the CPU executing a program stored in the memory.

The support base 20 is provided so as to extend in the width direction. In the present embodiment, the width direction of the liquid injection device 10 coincides with the width direction of the medium M. The medium M is conveyed on the support base 20 in a direction opposite to the depth direction. Therefore, the transport direction of the medium M is opposite to the depth direction.

The transport unit 30 includes a first transport roller pair 31 located behind the support base 20 in the depth direction and a second transport roller pair 32 located in front of the support base 20. The transport unit 30 includes a transport motor 33 that drives the first transport roller pair 31 and the second transport roller pair 32. By driving the first transfer roller pair 31 and the second transfer roller pair 32 by the transfer motor 33, the medium M sandwiched between the first transfer roller pair 31 and the second transfer roller pair 32 is placed on the surface of the support base 20. It is transported in the transport direction along the line.

The printing unit 40 includes a liquid injection unit 41 that injects liquid from the nozzle 44. The printing unit 40 of the present embodiment includes a guide shaft 42 provided so as to extend in the width direction, and a carriage 43 configured to reciprocate in the width direction by being guided by the guide shaft 42.

The printing unit 40 includes a carriage motor 45 for moving the carriage 43 along the guide shaft 42. The carriage 43 moves with the drive of the carriage motor 45. That is, the liquid injection device 10 of the present embodiment is a serial type in which the liquid injection unit 41 scans the medium M. The liquid injection device 10 may be configured as a line type in which the liquid injection unit 41 is provided long in the width direction.

As shown in FIG. 3, the liquid injection unit 41 has one or a plurality of nozzles 44 for injecting a liquid. The liquid injection unit 41 includes an individual liquid chamber 411 that communicates with the nozzle 44, an accommodating unit 413 that is partitioned from the individual liquid chamber 411 by the diaphragm 412, and an actuator 414 that is accommodated in the accommodating unit 413. The liquid injection unit 41 includes a common liquid chamber 415 that temporarily stores the supplied liquid and supplies the liquid to the plurality of individual liquid chambers 411.

The actuator 414 is, for example, a piezoelectric element that contracts when a driving voltage is applied. When the application of the driving voltage is released after the diaphragm 412 is deformed with the contraction of the actuator 414, the liquid in the individual liquid chamber 411 whose volume has changed is ejected as droplets from the nozzle 44.

The liquid injection device 10 includes a liquid supply flow path 110, a storage unit 120, an on-off valve 140, and a pressure mechanism 150 as a configuration of the liquid supply device 100. The liquid supply flow path 110 is configured to supply the liquid contained in the liquid supply source 101 to the liquid injection unit 41. The liquid supply flow path 110 connects the liquid injection unit 41 and the liquid supply source 101, which is a supply source of the liquid to the liquid injection unit 41. The liquid supply flow path 110 includes, for example, a tube.

The storage unit 120 is configured to store the liquid. The storage unit 120 is provided in the liquid supply flow path 110. The storage unit 120 is located between the liquid supply source 101 and the liquid injection unit 41 in the liquid supply flow path 110. The storage unit 120 stores the liquid supplied from the liquid supply source 101. Therefore, the storage unit 120 is located downstream of the liquid supply source 101 in the direction in which the liquid is supplied.

The storage portion 120 may be formed of a flexible member 121. The storage unit 120 of the present embodiment has a bag body 122 formed of a flexible member 121 having flexibility and a connecting body 123 connected to the liquid supply flow path 110. The liquid supplied from the liquid supply source 101 is stored in the bag body 122 through the connecting body 123. The bag body 122 expands and contracts depending on the amount of liquid to be stored. That is, the volume of the bag body 122 changes as it expands and contracts.

In the present embodiment, the liquid is supplied to the storage unit 120 by being pressurized from the liquid supply source 101 side, and the remaining amount RA of the liquid stored in the liquid supply source 101 reaches the limit value VL. The liquid is supplied from the storage unit 120 to the liquid injection unit 41.

The limit value VL is, for example, 0 or a small amount, which is less than the predetermined value VP. The predetermined value VP is an amount expected to be required for printing one image. When the remaining amount RA reaches the limit value VL, the liquid cannot be supplied from the liquid supply source 101 to the liquid injection unit 41. Therefore, the limit value VL is an amount that requires replacement of the liquid supply source 101.

When the remaining amount RA at the time of starting printing is equal to or higher than the predetermined value VP, the amount of liquid consumed by the liquid injection unit 41 is supplied from the liquid supply source 101. While the remaining amount RA of the liquid supply source 101 is larger than the limit value VL, the bag body 122 is maintained in an inflated state, and the amount of liquid stored in the storage unit 120 is substantially unchanged.

The storage unit 120 may be configured to store a liquid having a predetermined value of VP or more while the liquid is supplied from the liquid supply source 101. When the bag body 122 is inflated to the maximum, the storage unit 120 of the present embodiment stores a liquid having a predetermined value of VP or more. By doing so, even if the liquid of the liquid supply source 101 runs out during the printing of the image, the printing of the image can be continued by using the liquid stored in the storage unit 120. This reduces the risk of interrupting printing. In addition, deterioration of print quality such as color unevenness due to interruption of printing can be suppressed.

The on-off valve 140 is configured to open and close the liquid supply flow path 110. The on-off valve 140 is provided in the liquid supply flow path 110. The on-off valve 140 is provided in the liquid supply flow path 110 on the liquid supply source 101 side of the storage unit 120. Therefore, the on-off valve 140 is located between the storage unit 120 and the liquid supply source 101 in the liquid supply flow path 110. When the on-off valve 140 is opened, the liquid can flow from the liquid supply source 101 to the storage unit 120. When the on-off valve 140 is closed, the flow of liquid from the liquid supply source 101 to the storage unit 120 is blocked.

The on-off valve 140 may be, for example, a solenoid valve that opens and closes the valve by a solenoid, or an electric valve that opens and closes the valve by an electric motor. The on-off valve 140 may be a fluid pressure valve that opens and closes the valve by a fluid pressure cylinder, or may be another control valve.

The pressure mechanism 150 is configured to apply pressure to the liquid in the storage unit 120 from the outside. The pressure mechanism 150 may be configured to exert pressure in the reservoir 120 via the flexible member 121. The pressure mechanism 150 may apply a negative pressure from the outside into the storage unit 120 to displace the flexible member 121 so as to increase the volume of the storage unit 120.

The pressure mechanism 150 of the present embodiment inflates the bag body 122 so as to increase the volume of the storage unit 120 by depressurizing the outside of the storage unit 120. When the bag body 122 swells, the pressure in the storage unit 120 decreases. In this way, the pressure mechanism 150 applies a negative pressure from the outside of the storage unit 120 into the storage unit 120. The pressure mechanism 150 may be configured to apply a negative pressure from the outside into the storage portion 120 by displace the flexible member 121 by, for example, a mechanical element such as a spring or a lever.

The pressure mechanism 150 may include an accommodating body 152 having a pressure chamber 151 accommodating the storage unit 120, and a storage pump 153 for depressurizing the inside of the pressure chamber 151. The pressure mechanism 150 depressurizes the inside of the pressure chamber 151 by the storage pump 153, so that a negative pressure is applied to the inside of the storage unit 120 from the outside. When the pressure inside the pressure chamber 151 is reduced, the bag body 122 swells. As a result, a negative pressure acts from outside the storage unit 120 into the storage unit 120. The inflated bag body 122 comes into contact with the inner wall 154 of the housing body 152 forming the pressure chamber 151. When the storage unit 120 stores a liquid having a predetermined value of VP or more, the flexible member 121 forming the bag body 122 comes into contact with the inner wall 154.

The pressure mechanism 150 of the present embodiment can also pressurize the inside of the pressure chamber 151. When the inside of the pressure chamber 151 is pressurized, the bag body 122 shrinks. The pressure mechanism 150 adjusts the pressure in the storage unit 120 by reducing the pressure and pressurizing the inside of the pressure chamber 151. The pressure mechanism 150 may be configured to open the pressure chamber 151 to the atmosphere.

The pressure mechanism 150 may include a pressure adjusting flow path 155 that connects the storage pump 153 located outside the housing 152 and the pressure chamber 151. The storage pump 153 pressurizes or depressurizes the pressure chamber 151 through the pressure adjusting flow path 155. The storage pump 153 may be located inside the housing 152.

The liquid injection device 10 includes a discharge mechanism 50 configured to reduce the pressure in the liquid supply flow path 110. The discharge mechanism 50 is configured to discharge the liquid in the liquid supply flow path 110 from the liquid injection unit 41 side of the storage unit 120 in the liquid supply flow path 110 by reducing the pressure in the liquid supply flow path 110.

The discharge mechanism 50 of the present embodiment includes a cap 51 capable of covering the nozzle 44 of the liquid injection unit 41 and a suction pump 52 that sucks the inside of the cap 51. The cap 51 caps the liquid injection unit 41 by contacting the liquid injection unit 41. Capping is to form a space in which the nozzle 44 opens. Capping is performed to prevent the nozzle 44 from drying out.

When the suction pump 52 is driven with the cap 51 capping the liquid injection unit 41, a negative pressure acts on the nozzle 44, and the liquid is forcibly discharged from the nozzle 44. This is called suction cleaning. That is, the discharge mechanism 50 of the present embodiment discharges the liquid in the liquid supply flow path 110 from the liquid injection unit 41 by depressurizing the liquid supply flow path 110 through the liquid injection unit 41.

When the suction cleaning is performed, air bubbles, foreign substances, and the like in the liquid injection section 41 and the liquid supply flow path 110 are discharged together with the liquid. Therefore, the discharge mechanism 50 depressurizes the liquid supply flow path 110 in order to maintain the liquid injection device 10.

The discharge mechanism 50 may include a waste liquid tank 53 for collecting the waste liquid discharged from the liquid injection unit 41. In this way, for example, the waste liquid discharged to the cap 51 by suction cleaning can be collected by the waste liquid tank 53. The waste liquid tank 53 may directly collect the discharged waste liquid.

The discharge mechanism 50 may include a regulator 54 that adjusts the pressure in the cap 51. At the time of capping, the regulator 54 passes the pressure inside the cap 51 through the air so that the pressure inside the cap 51 becomes a predetermined pressure, for example, from -2 kPa to + 2 kPa. That is, the regulator 54 adjusts the pressure in the cap 51 to a predetermined pressure by taking in air into the cap 51. The regulator 54 may be an air release valve that closes when a negative pressure is applied to the nozzle 44 and opens when the inside of the cap 51 and the atmosphere are allowed to pass through.

The liquid injection device 10 is configured to perform a maintenance operation of reducing the pressure of the liquid supply flow path 110 by the discharge mechanism 50 in a state where the liquid supply flow path 110 is closed by the on-off valve 140. When the liquid supply flow path 110 is depressurized by the discharge mechanism 50 with the liquid supply flow path 110 closed by the on-off valve 140, negative pressure is accumulated in a portion of the liquid supply flow path 110 downstream of the on-off valve 140. When negative pressure is accumulated in the liquid supply flow path 110, the volume of bubbles in the liquid supply flow path 110 increases. This facilitates the discharge of air bubbles in the liquid supply flow path 110.

In the present embodiment, the liquid is discharged from the nozzle 44 by opening the on-off valve 140 in a state where the negative pressure is accumulated in the liquid supply flow path 110. In this way, the discharge mechanism 50 accumulates the negative pressure generated by depressurizing the liquid supply flow path 110, and then vigorously discharges the liquid in the liquid supply flow path 110 from the nozzle 44 by the accumulated negative pressure. This is generally called chalk cleaning. Chalk cleaning is performed to maintain the liquid injection device 10. When the choke cleaning is executed, air bubbles, foreign substances, and the like in the liquid injection section 41 and the liquid supply flow path 110 are discharged together with the liquid. The choke cleaning is mainly performed for the purpose of discharging air bubbles, foreign substances, and the like in the liquid supply flow path 110.

When performing choke cleaning, the liquid injection device 10 of the present embodiment first closes the on-off valve 140. Next, the discharge mechanism 50 depressurizes the liquid supply flow path 110 from the liquid injection unit 41 side. As a result, negative pressure is accumulated in the portion of the liquid supply flow path 110 that is closer to the liquid injection portion 41 than the on-off valve 140, that is, the portion of the liquid supply flow path 110 that is downstream of the on-off valve 140. Next, the on-off valve 140 is opened. As a result, the liquid is vigorously discharged from the nozzle 44 by the depressurization of the discharge mechanism 50.

In the maintenance operation, when the liquid supply flow path 110 is depressurized by the discharge mechanism 50 with the liquid supply flow path 110 closed by the on-off valve 140, the storage unit 120 is also depressurized. When a negative pressure acts in the storage unit 120 due to the decompression of the discharge mechanism 50, the liquid may flow out from the storage unit 120. In this case, the liquid stored in the storage unit 120 is discharged in order to discharge air bubbles, foreign substances, and the like in the liquid supply flow path 110. Therefore, the amount of liquid consumed due to maintenance increases.

When the liquid flows out from the storage unit 120 due to the decompression of the discharge mechanism 50, it becomes difficult to accumulate the negative pressure in the liquid supply flow path 110. In particular, when the storage unit 120 is formed by the flexible member 121, when the decompression by the discharge mechanism 50 acts in the storage unit 120, the flexible member 121 is displaced so that the volume of the storage unit 120 becomes smaller. In this case, if a sufficient negative pressure is to be accumulated in the liquid supply flow path 110, most of the liquid in the storage portion 120 will flow out as the flexible member 121 is displaced. That is, when the choke cleaning is performed in such a state, most of the liquid stored in the storage unit 120 is discharged, so that the consumption of the liquid tends to increase.

The liquid injection device 10 operates so as to reduce the consumption of the liquid in the maintenance operation. In the maintenance operation, the control unit 60 controls the pressure mechanism 150 so that a negative pressure equal to or higher than the negative pressure acting on the storage unit 120 due to the decompression of the discharge mechanism 50 acts on the storage unit 120. At this time, the negative pressure acting in the storage unit 120 due to the decompression of the discharge mechanism 50 is, for example, −50 kPa with respect to the atmospheric pressure. In the maintenance operation, the control unit 60 controls the pressure mechanism 150 so that a negative pressure of, for example, -60 kPa is applied to the storage unit 120 as a negative pressure of -50 kPa or more. That is, the pressure mechanism 150 causes a pressure smaller than the pressure acting in the storage unit 120 due to the decompression of the discharge mechanism 50 to act in the storage unit 120 from the outside. In this way, the possibility that the liquid will flow out from the storage unit 120 due to the decompression of the discharge mechanism 50 is reduced.

In the maintenance operation, the pressure mechanism 150 of the present embodiment applies a negative pressure from the outside into the storage unit 120 so that the flexible member 121 is not displaced by the decompression of the discharge mechanism 50. For example, the pressure mechanism 150 depressurizes the pressure chamber 151 so that the flexible member 121 comes into contact with the inner wall 154 of the housing 152 during the maintenance operation. By doing so, in the maintenance operation, the amount of the liquid stored in the storage unit 120 can be maintained at a predetermined value VP or more.

When the empty storage unit 120 is filled with the liquid, the pressure mechanism 150 pressurizes the inside of the storage unit 120 by sending a gas to the pressure chamber 151. When the inside of the storage unit 120 is pressurized, the air in the storage unit 120 is discharged. As a result, the storage unit 120 can be filled with the liquid. When the amount of liquid in the liquid supply source 101 becomes small, the pressure mechanism 150 operates so that the liquid can be supplied from the storage unit 120 by starting to pressurize the inside of the storage unit 120.

Next, the liquid supply device 100 of this embodiment will be described.
The liquid supply device 100 includes a holding unit 102 configured to attach and detach a liquid supply source 101 that houses the liquid. The liquid supply flow path 110 is configured to supply the liquid to the liquid injection unit 41 from the liquid supply source 101 mounted on the holding unit 102.

The liquid supply source 101 may be of a structure capable of accommodating a liquid, and may be, for example, a replaceable cartridge type or a tank type capable of replenishing the liquid. The liquid supply source 101 is provided so as to correspond to the number of types of liquid used by the liquid injection device 10.

The liquid supply device 100 may include a remaining amount acquisition unit 103 for acquiring the remaining amount RA of the liquid contained in the liquid supply source 101. The remaining amount acquisition unit 103 may detect the liquid contained in the liquid supply source 101 by an optical sensor. The remaining amount acquisition unit 103 of the present embodiment includes a light emitting unit 105 that emits light toward the prism 104 of the liquid supply source 101, and a light receiving unit 106 that receives light returning from the prism 104. The prism 104 is, for example, a triangular prism. The traveling direction of the light incident on the prism 104 changes depending on the amount of liquid contained in the liquid supply source 101.

Specifically, when the liquid is sufficiently contained in the liquid supply source 101, the area where the prism 104 and the liquid come into contact with each other is large. Therefore, the light incident on the prism 104 travels in the liquid so as to pass through the prism 104, and the light returning to the light receiving unit 106 is small. When the amount of liquid contained in the liquid supply source 101 is reduced and the prism 104 is exposed from the liquid, the area of contact between the prism 104 and the liquid is small. Therefore, the light incident on the prism 104 is reflected so as to travel in the prism 104 and reaches the light receiving unit 106. Therefore, the amount of light received by the light receiving unit 106 when the prism 104 is exposed from the liquid is larger than that when the prism 104 is hidden by the liquid.

The remaining amount acquisition unit 103 outputs the amount of light received by the light receiving unit 106 to the control unit 60. The control unit 60 determines whether or not the remaining amount RA of the liquid contained in the liquid supply source 101 is a predetermined value VP or less or a limit value VL or less based on the amount of light received by the light receiving unit 106.

The liquid supply flow path 110 of the present embodiment has a first liquid flow path 111 and a second liquid flow path 112. The first liquid flow path 111 connects the liquid supply source 101 and the storage unit 120. The second liquid flow path 112 connects the storage unit 120 and the liquid injection unit 41. The first liquid flow path 111 and the second liquid flow path 112 are connected to the connecting body 123 of the storage unit 120.

The liquid supply flow path 110 may be any flow path through which the liquid can flow. The liquid supply flow path 110 may be formed of, for example, an elastically deformable tube, or may be formed of a flow path forming member made of a hard resin material. The liquid supply flow path 110 may be formed by attaching a film member to the flow path forming member in which the groove is formed.

The liquid supply device 100 may include a supply mechanism 170 that supplies a liquid toward the liquid injection unit 41. The supply mechanism 170 pressurizes the liquid in the liquid supply source 101 to the supply pressure so that the liquid can be ejected from the nozzle 44. The supply mechanism 170 is configured to supply the pressurized liquid toward the liquid injection unit 41 via the liquid supply flow path 110.

The supply mechanism 170 is provided in the liquid supply flow path 110. The supply mechanism 170 is located between the liquid supply source 101 and the storage unit 120 in the liquid supply flow path 110. Therefore, the storage unit 120 stores the liquid pressurized by the supply mechanism 170. The supply mechanism 170 of this embodiment is provided in the first liquid flow path 111. The liquid of the liquid supply source 101 is supplied to the liquid injection unit 41 by the supply mechanism 170 via the storage unit 120.

The supply mechanism 170 of the present embodiment includes a positive displacement pump 171 and a first regulation valve 172 and a second regulation valve 173 which is an example of the regulation valve. The first regulation valve 172 is located upstream of the positive displacement pump 171 in the liquid supply flow path 110. The second regulation valve 173 is located downstream of the positive displacement pump 171 in the liquid supply flow path 110. The first regulation valve 172 and the second regulation valve 173 of the present embodiment are one-way valves that allow the flow of liquid from upstream to downstream in the liquid supply flow path 110 and regulate the flow of liquid from downstream to upstream. is there. The first regulation valve 172 and the second regulation valve 173 are provided between the storage unit 120 and the liquid supply source 101 in the liquid supply flow path 110, and regulate the flow of liquid from the storage unit 120 to the liquid supply source 101. .. The first regulation valve 172 and the second regulation valve 173 may be configured to open and close the liquid supply flow path 110 in the same manner as the on-off valve 140.

The volumetric pump 171 is configured to apply pressure to the liquid by reciprocating the flexible flexible membrane 174. The positive displacement pump 171 has a pump chamber 175 and a negative pressure chamber 176 separated by a flexible membrane 174. The positive displacement pump 171 includes a decompression unit 177 for depressurizing the negative pressure chamber 176, and a pressing member 178 for pressing the flexible film 174 toward the pump chamber 175 side. The pressing member 178 is provided in the negative pressure chamber 176.

When the decompression unit 177 depressurizes the negative pressure chamber 176, the flexible membrane 174 is displaced so that the volume of the pump chamber 175 becomes large. At this time, the liquid is drawn into the pump chamber 175 from the liquid supply source 101. When the decompression of the negative pressure chamber 176 by the decompression unit 177 is stopped, the flexible film 174 is displaced against the pressing member 178 so that the volume of the pump chamber 175 becomes smaller. At this time, the liquid is pushed out from the pump chamber 175. That is, the positive displacement pump 171 of the present embodiment is composed of a diaphragm pump.

The supply mechanism 170 pressurizes the liquid by the pressing member 178 pressing the liquid in the pump chamber 175 through the flexible membrane 174. As a result, the supply mechanism 170 supplies the liquid toward the liquid injection unit 41. The pressing force for pressurizing the liquid by the supply mechanism 170 is set by the pressing force of the pressing member 178.

The liquid supply device 100 may include a first filter unit 210, a second filter unit 220, a third filter unit 230, a static mixer 250, a liquid storage unit 260, a degassing mechanism 270, and a hydraulic pressure adjusting mechanism 280. The first filter unit 210, the second filter unit 220, the third filter unit 230, the static mixer 250, the liquid storage unit 260, the degassing mechanism 270, and the hydraulic pressure adjusting mechanism 280 are provided in the liquid supply flow path 110 and are provided in the storage unit. It is located between 120 and the liquid injection unit 41. In the present embodiment, the first filter unit 210, the static mixer 250, the liquid storage unit 260, the degassing mechanism 270, the second filter unit 220, the hydraulic pressure adjusting mechanism 280, and the third filter unit 230 are second in order from the upstream. It is provided in the liquid flow path 112.

In the first filter unit 210, the second filter unit 220, and the third filter unit 230, the amount of foreign matter collected increases as the usage time increases. Therefore, the liquid injection device 10 may be configured so that at least one of the first filter unit 210, the second filter unit 220, and the third filter unit 230 can be exchanged. For example, as shown in FIG. 2, the first filter unit 210 may be provided at a position exposed from the housing 12 when the cover 18 of the housing 12 is opened.

As shown in FIG. 3, the first filter unit 210 includes a first filter 211 that collects foreign matter, a first upstream filter chamber 212 located upstream of the first filter 211, and a first filter 211. It has a first downstream filter chamber 213 located downstream. The first upstream filter chamber 212 is located below the first downstream filter chamber 213. The first upstream filter chamber 212 is provided in a substantially conical shape or a substantially truncated cone shape. The first filter 211 is formed in a substantially disk shape so as to form the bottom surface of the first upstream filter chamber 212. The height of the first upstream filter chamber 212 may be smaller than the diameter of the first filter 211.

The second filter unit 220 includes a second filter 221 that collects foreign matter, a second upstream filter chamber 222 that is located upstream of the second filter 221 and a second downstream that is located downstream of the second filter 221. It has a side filter chamber 223.

The third filter unit 230 includes a third filter 231 that collects foreign matter, a third upstream filter chamber 232 that is located upstream of the third filter 231 and a third downstream that is located downstream of the third filter 231. It has a side filter chamber 233.

The first filter 211, the second filter 221 and the third filter 231 may be formed so that the filtration area through which the liquid can pass is larger than the flow path cross-sectional area of the liquid supply flow path 110. As the first filter 211, the second filter 221 and the third filter 231, for example, a mesh-like body, a porous body, a perforated plate having fine through holes formed, or the like can be used. The first filter 211, the second filter 221 and the third filter 231 may use different types of filters and different shapes.

Examples of the mesh-like filter include wire mesh, resin mesh, mesh filter, and metal fiber. Examples of the metal fiber filter include a felt filter in which a thin stainless wire is made into a felt shape, and a metal sintered filter in which a thin stainless wire is compression-sintered. Examples of the perforated plate filter include an electroforming metal filter, an electron beam processed metal filter, and a laser beam processed metal filter.

The static mixer 250 includes a plurality of configurations that divide the flow of the liquid in the direction of the flow of the liquid. The static mixer 250 reduces the bias of the concentration in the liquid by dividing, converting, and reversing the liquid flowing through the static mixer 250.

The liquid storage unit 260 presses the pressurizing chamber 261 for storing the liquid, the elastic film 262 forming a part of the wall surface of the pressurizing chamber 261, and the elastic film 262 in the direction of reducing the volume of the pressurizing chamber 261. It has one pressing member 263. The liquid stored in the pressurizing chamber 261 is pressurized by the first pressing member 263.

The liquid storage unit 260 pressurizes the liquid stored in the pressurizing chamber 261 at a pressure lower than the supply pressure pressurized by the supply mechanism 170 when supplying the liquid to the liquid injection unit 41. The supply pressure pressurized by the supply mechanism 170 when supplying the liquid to the liquid injection unit 41 is, for example, 30 kPa. Therefore, the liquid storage unit 260 pressurizes the liquid stored in the pressurizing chamber 261 at, for example, 10 kPa. Specifically, the pressure acting on the liquid stored in the pressurizing chamber 261 by the elastic film 262 pressed against the first pressing member 263 is supplied to supply the liquid from the liquid supply source 101 toward the liquid injection unit 41. It is lower than the pressure exerted by the mechanism 170. Therefore, when the liquid supply pressure from the liquid supply source 101 does not drop to the liquid storage portion 260, the volume of the pressurizing chamber 261 increases against the pressing force of the first pressing member 263. The elastic film 262 is displaced.

The degassing mechanism 270 includes a degassing chamber 271 for temporarily storing a liquid, an exhaust chamber 273 partitioned from the degassing chamber 271 by a degassing membrane 272, and an exhaust passage 274 for communicating the exhaust chamber 273 to the outside.

The degassing membrane 272 has a property of allowing gas to pass through but not liquid to pass through. As the degassing film 272, for example, a film made by specially stretching polytetrafluoroethylene with a large number of fine pores of about 0.2 micron formed can be adopted. When a liquid containing gas flows into the degassing chamber 271, only the gas passes through the degassing membrane 272 and enters the exhaust chamber 273. The gas that has entered the exhaust chamber 273 is discharged to the outside through the exhaust passage 274. As a result, bubbles and dissolved gas mixed in the liquid stored in the degassing chamber 271 are removed.

In the degassing mechanism 270, the exhaust chamber 273 may be located above the degassing chamber 271. Bubbles and dissolved gas mixed in the liquid tend to float in the liquid. Therefore, when the exhaust chamber 273 is located above the degassing chamber 271, it becomes easy to remove air bubbles and dissolved gas mixed in the liquid.

The degassing mechanism 270 may include a decompression pump 275 that depressurizes the exhaust chamber 273. The decompression pump 275 decompresses the exhaust chamber 273 through the exhaust passage 274 to remove air bubbles and dissolved gas mixed in the liquid stored in the degassing chamber 271. For example, if the pressure of the exhaust chamber 273 can be made lower than the pressure of the degassing chamber 271 by using a member such as a spring, the decompression pump 275 may not be provided. In the present embodiment, the pressure in the degassing chamber 271 becomes higher than the pressure in the exhaust chamber 273 due to the pressurization of the supply mechanism 170.

The hydraulic pressure adjusting mechanism 280 of the present embodiment is provided integrally with the second filter unit 220 at a position downstream of the second filter unit 220. The hydraulic pressure adjusting mechanism 280 includes a liquid chamber 282 that communicates with the second downstream filter chamber 223 via the communication hole 281 and a valve body 283 that can open and close the communication hole 281. The hydraulic pressure adjusting mechanism 280 includes a pressure receiving member 284 whose base end side is housed in the second downstream side filter chamber 223 and whose tip end side is housed in the liquid chamber 282.

The liquid chamber 282 of the hydraulic pressure adjusting mechanism 280 is capable of storing liquid. A part of the wall surface of the liquid chamber 282 is formed by a flexible wall 285 that can be flexed and displaced. The valve body 283 may be, for example, an elastic body such as rubber or resin attached to the base end portion of the pressure receiving member 284 located in the second downstream filter chamber 223.

The hydraulic pressure adjusting mechanism 280 includes a second pressing member 286 housed in the second downstream filter chamber 223 and a third pressing member 287 housed in the liquid chamber 282. The second pressing member 286 presses the valve body 283 in the direction of closing the communication hole 281 via the pressure receiving member 284. The third pressing member 287 bends and displaces the flexible wall 285 in a direction that reduces the volume of the liquid chamber 282, so that when the flexible wall 285 pushes the pressure receiving member 284, the pressure receiving member 284 is pushed back.

When the internal pressure of the liquid chamber 282 decreases and the force of the flexible wall 285 pushing the pressure receiving member 284 exceeds the pressing force of the second pressing member 286 and the third pressing member 287, the valve body 283 has the communication hole 281. To open. When the liquid flows into the liquid chamber 282 from the second downstream side filter chamber 223 by opening the communication hole 281, the internal pressure of the liquid chamber 282 rises. As a result, the valve body 283 closes the communication hole 281 by the pressing force of the second pressing member 286 and the third pressing member 287 before the internal pressure of the liquid chamber 282 rises to the positive pressure. In this way, the internal pressure of the liquid chamber 282 is maintained within the range of negative pressure corresponding to the pressing force of the second pressing member 286 and the third pressing member 287.

The internal pressure of the liquid chamber 282 decreases as the liquid is discharged from the liquid injection unit 41. The valve body 283 autonomously opens and closes the communication hole 281 according to the difference pressure between the atmospheric pressure, which is the external pressure of the liquid chamber 282, and the internal pressure of the liquid chamber 282. Therefore, the hydraulic pressure adjusting mechanism 280 is a differential pressure valve. The differential pressure valve is also called a pressure reducing valve or a self-sealing valve. The hydraulic pressure adjusting mechanism 280 adjusts the pressure of the liquid supplied to the liquid injection unit 41 to an adjusting pressure that can be injected from the nozzle 44 and is lower than the supply pressure. The adjusting pressure is, for example, -1 kPa.

The hydraulic pressure adjusting mechanism 280 may be provided with a valve opening mechanism 290 that forcibly opens the communication hole 281 and supplies the liquid to the liquid injection unit 41. For example, the valve opening mechanism 290 includes a pressure bag 292 housed in a storage chamber 291 partitioned from the liquid chamber 282 by a flexible wall 285, and a pressure flow path 293 for allowing gas to flow into the pressure bag 292. ..

In the valve opening mechanism 290, the pressure bag 292 expands due to the gas flowing through the pressure flow path 293, and the flexible wall 285 is flexed and displaced in the direction of reducing the volume of the liquid chamber 282, thereby forcibly moving the communication hole 281. To open. The liquid supply device 100 can perform pressure cleaning in which the liquid is discharged from the liquid injection unit 41 by pressurizing and supplying the liquid from the liquid supply source 101 to the liquid injection unit 41 with the communication hole 281 open.

When the pressure reducing pump 275 is provided, the liquid supply device 100 may be configured so that the valve opening mechanism 290 and the degassing mechanism 270 share the pressure reducing pump 275. For example, the pressurizing flow path 293 may be connected to the exhaust passage 274, and the decompression pump 275 may be configured to be capable of driving both pressurization and depressurization. In this case, the check valve 187 may be provided in the exhaust passage 274. In such a configuration, the decompression pump 275 may be driven by pressurization to send gas to the pressurizing bag 292, and the decompression pump 275 may be driven by decompression to depressurize the exhaust chamber 273.

Next, the storage unit 120 and the pressure mechanism 150 will be described.
The storage unit 120 is provided so as to correspond to the number of liquid supply sources 101. That is, the storage unit 120 is provided so as to correspond to the number of types of liquid used by the liquid injection device 10. For example, one storage unit 120 may be provided for one liquid supply source 101, or two storage units 120 may be provided for one liquid supply source 101.

As shown in FIG. 4, a plurality of storage units 120 are provided in the present embodiment. The housing 152 of the pressure mechanism 150 has a plurality of pressure chambers 151. Therefore, the accommodation body 152 is configured to accommodate a plurality of storage units 120. The housing 152 may be configured to have one pressure chamber 151. In this case, a plurality of housings 152 are provided so as to correspond to the plurality of storage units 120.

In the housing 152, the plurality of pressure chambers 151 are located so as to be aligned in the vertical direction. The housing 152 of the present embodiment has six pressure chambers 151. Therefore, the accommodating body 152 is configured to accommodate six storage units 120.

The plurality of pressure chambers 151 are configured so that their spaces are connected by slits 156 provided in the accommodating body 152. Therefore, when the storage pump 153 depressurizes one pressure chamber 151, the other pressure chambers 151 are also depressurized. When the storage pump 153 pressurizes one pressure chamber 151, the other pressure chambers 151 are also pressurized. The pressure mechanism 150 may include a storage pump 153 for each pressure chamber 151. In this case, the pressure can be adjusted for each pressure chamber 151. In the pressure mechanism 150, the storage pump 153 sends gas to the pressure chamber 151 of the housing 152 to pressurize the inside of the storage unit 120, and the storage pump 153 discharges the gas from the pressure chamber 151 of the housing 152 to store the gas. A negative pressure is applied to the portion 120.

The inner wall 154 of the accommodating body 152 forming the pressure chamber 151 may be arranged so as to come into contact with the flexible member 121 displaced so as to increase the volume of the storage portion 120. In this way, it is possible to prevent the flexible member 121 from being excessively displaced. That is, it is possible to prevent the bag body 122 from swelling excessively. As a result, damage to the flexible member 121 due to excessive displacement can be reduced.

As shown in FIG. 5, the storage unit 120 may have an introduction hole 124 for introducing the liquid into the storage unit 120 and a lead-out hole 125 for guiding the liquid out of the storage unit 120. The introduction hole 124 and the lead-out hole 125 of the present embodiment are provided in the connecting body 123 and open in the bag body 122. The liquid introduced from the introduction hole 124 is led out from the outlet hole 125 via the inside of the storage unit 120.

The connecting body 123 may have a connecting path 126 connecting the introduction hole 124 and the lead-out hole 125. In this way, even when the bag body 122 is completely withered, the liquid can flow from the introduction hole 124 to the outlet hole 125 through the connection path 126.

The storage unit 120 may have an introduction pipe 127 connected to the first liquid flow path 111 and a lead-out pipe 128 connected to the second liquid flow path 112. The introduction pipe 127 and the outlet pipe 128 of the present embodiment are provided in the connecting body 123. An introduction hole 124 opens at one end of the introduction pipe 127. A lead-out hole 125 opens at one end of the lead-out pipe 128. The introduction pipe 127 and the outlet pipe 128 may be provided independently.

The bag body 122 may be formed by adhering two flexible members 121. The flexible member 121 is provided, for example, as a rectangular sheet. The edge portion of the flexible member 121 is an adhesive portion 129 to which the flexible members 121 are bonded to each other. The flexible member 121 may be adhered by an adhesive, or may be welded by heat or a solvent. The connecting body 123 is positioned so as to be sandwiched between the adhesive portions 129 and is adhered to the adhesive portion 129.

In the present embodiment, the flat bag body 122 is arranged in a flat state so as to be flat on the planes of the X-axis and the Y-axis. The bag body 122 may be arranged in a vertically placed state so as to be flat on the planes of the Y axis and the Z axis, or may be arranged in a vertically placed state so as to be flat on the planes of the Z axis and the X axis. You may.

Next, a control method of the liquid injection device 10 will be described with reference to the flowchart shown in FIG. This supply routine is executed at the timing when the instruction to start printing is input. The control unit 60 may execute the supply routine shown in FIG. 6 when the power of the liquid injection device 10 is turned on, wait for the printing start command, and execute the printing routine shown in FIG. 7.

As shown in FIG. 6, in step S101, the control unit 60 drives the supply mechanism 170. In step S102, the control unit 60 determines whether or not a predetermined time has elapsed since the supply mechanism 170 was driven. The predetermined time is the time required to supply the liquid from the liquid supply source 101 to the storage unit 120 and fill the storage unit 120 with the liquid. If the predetermined time has not elapsed, step S102 becomes NO, and the control unit 60 waits until the predetermined time elapses.

When the predetermined time elapses, step S102 becomes YES. The control unit 60 shifts the process to step S103, and determines whether or not the remaining amount RA of the liquid contained in the liquid supply source 101 is equal to or less than the limit value VL. When the remaining amount RA is equal to or less than the limit value VL, step S103 becomes YES, and the control unit 60 shifts the process to step S104.

In step S104, the control unit 60 displays, for example, on the operation panel 17 prompting the replacement of the liquid supply source 101, and notifies that the remaining amount RA is the limit value VL. In step S105, the control unit 60 stops driving the supply mechanism 170 and ends the supply routine.

In step S103, if the remaining amount RA is larger than the limit value VL, step S103 becomes NO. The control unit 60 shifts the process to step S106 and executes the print routine.

Next, the printing routine will be described with reference to the flowchart shown in FIG.
In step S201, the control unit 60 determines whether or not the remaining amount RA is equal to or less than the predetermined value VP. When the remaining amount RA is equal to or less than the predetermined value VP, step S201 becomes YES, and the control unit 60 shifts the process to step S202. In step S202, the control unit 60 drives the pressure mechanism 150 to perform prepressurization. In step S203, the control unit 60 starts printing and shifts the process to step S209.

If the remaining amount RA is larger than the predetermined value VP in step S201, step S201 becomes NO, and the control unit 60 shifts the process to step S204. In step S204, the control unit 60 starts printing.

In step S205, the control unit 60 determines whether or not the remaining amount RA is equal to or less than the predetermined value VP, as in step S201. When the remaining amount RA is equal to or less than the predetermined value VP, step S205 becomes YES, and the control unit 60 shifts the process to step S206. In step S206, the control unit 60 drives the pressure mechanism 150 to perform preliminary pressurization, and the process shifts to step S209.

In step S205, when the remaining amount RA is larger than the predetermined value VP, step S205 becomes NO, and the control unit 60 shifts the process to step S207. In step S207, the control unit 60 determines whether or not printing is completed. If printing is not completed, step S207 becomes NO, and the control unit 60 shifts the process to step S205. When printing is completed, step S207 becomes YES, and the control unit 60 shifts the process to step S208. In step S208, the control unit 60 stops driving the supply mechanism 170 and ends the printing routine.

In step S209, the control unit 60 determines whether or not the remaining amount RA is equal to or less than the limit value VL. When the remaining amount RA is larger than the limit value VL, step S209 becomes NO, and the control unit 60 shifts the process to step S210. In step S210, the control unit 60 determines whether or not printing is completed. If printing is not completed, step S210 becomes NO, and the control unit 60 shifts the process to step S209. When printing is completed, step S210 becomes YES, and the control unit 60 shifts the process to step S211. In step S211 the control unit 60 stops driving the supply mechanism 170 and ends the printing routine.

In step S209, when the remaining amount RA is equal to or less than the limit value VL, step S209 becomes YES, and the control unit 60 shifts the process to step S212. In step S212, the control unit 60 drives the pressure mechanism 150 to mainly pressurize the storage unit 120. In step S213, the control unit 60 stops driving the supply mechanism 170. In step S214, as in step S104, it is notified that the remaining amount RA is the limit value VL.

In step S215, the control unit 60 determines whether or not printing is completed. If printing is not completed, step S215 becomes NO, and the control unit 60 waits until printing is completed. When printing is completed, step S215 becomes YES, and the control unit 60 ends the printing routine.

The operation of this embodiment will be described.
The control unit 60 drives the supply mechanism 170 to supply the liquid from the liquid supply source 101 toward the storage unit 120. When the remaining amount RA of the liquid supply source 101 is larger than the predetermined value VP, the pressure mechanism 150 stops driving the storage pump 153 and opens the pressure chamber 151 to the atmosphere. The maximum amount of liquid is stored in the storage unit 120. That is, a liquid having a predetermined value of VP or more is stored in the storage unit 120.

When the remaining amount RA of the liquid supply source 101 reaches the limit value VL, the liquid cannot be supplied from the liquid supply source 101. When the liquid is supplied from the storage unit 120 to the liquid injection unit 41 in a state where the liquid is not supplied from the liquid supply source 101, the amount of the liquid stored in the storage unit 120 may be smaller than the predetermined value VP. .. Therefore, when the remaining amount RA is equal to or less than the limit value VL at the start of printing, the control unit 60 prompts the replacement of the liquid supply source 101 or the replenishment of the liquid without starting printing.

In a state where the remaining amount RA is larger than the limit value VL and the liquid can be supplied from the liquid supply source 101, the liquid of the predetermined value VP or more is stored in the storage unit 120. If a liquid of a predetermined value VP or more is stored in the storage unit 120 at the start of printing, printing can be completed by the liquid in the storage unit 120 even if the remaining amount RA reaches the limit value VL during printing.

When the liquid is consumed in the liquid injection unit 41 by printing or the like, the liquid is supplied from the liquid supply source 101, and the remaining amount RA is reduced. The control unit 60 drives the pressure mechanism 150 to pressurize the liquid in the storage unit 120 when the remaining amount RA of the liquid stored in the liquid supply source 101 reaches a predetermined value VP. This pressurization is called pre-pressurization, and the pressure applied to the liquid in the reservoir 120 by pre-pressurization is called pre-pressurization. If the remaining amount RA is equal to or less than the predetermined value VP at the start of printing, the control unit 60 may start printing after performing preliminary pressurization.

When the remaining amount RA reaches a predetermined value VP, the pressure applied to the liquid in the storage unit 120 by the pressure mechanism 150 is lower than the supply pressure of 30 kPa at which the supply mechanism 170 pressurizes the liquid, and the hydraulic pressure adjusting mechanism 280. May be higher than the adjustment pressure to be adjusted. The pressure mechanism 150 of the present embodiment prepresses the liquid in the storage unit 120 at 25 kPa. As a result, the liquid can be continuously supplied from the liquid supply source 101 to the storage unit 120 even when the liquid in the storage unit 120 is pressurized.

When the remaining amount RA reaches a predetermined value VP and the liquid is supplied from the liquid supply source 101 even after the pressure mechanism 150 is driven to pressurize the liquid in the storage unit 120, the remaining amount RA reaches the limit value VL. Become. When the remaining amount RA reaches the limit value VL, the control unit 60 may set the pressure applied to the liquid in the storage unit 120 by the pressure mechanism 150 to be the same as the supply pressure. That is, the pressure mechanism 150 may pressurize the liquid in the storage unit 120 to 30 kPa. This pressurization is called main pressurization.

The time required to raise the preliminary pressure to the supply pressure may be shorter than the time required to divide the volume of the pump chamber 175 by the amount of liquid consumed per second in the liquid injection unit 41. As a result, the liquid in the pump chamber 175 is supplied to the storage unit 120, and the liquid in the storage unit 120 can be pressurized by the supply pressure while the liquid in the storage unit 120 has a predetermined value of VP or more. The time required to raise the preliminary pressure to the supply pressure may be shorter than the time required to divide the volume of the inflated bag body 122 by the amount of liquid consumed per second in the liquid injection unit 41.

When the plurality of pressure chambers 151 can be individually pressurized, the control unit 60 sets the pressure applied to the liquid in the storage unit 120 to be higher than the supply pressure when the remaining amount RA reaches the limit value VL. May be good. For example, the control unit 60 may pressurize the storage unit 120 to which the liquid has been supplied from the liquid supply source 101 that has reached the limit value VL to 40 kPa.

The first liquid flow path 111 is provided with a second regulation valve 173. Even if the pressure mechanism 150 pressurizes the storage unit 120 above the supply pressure, the second regulation valve 173 regulates the flow of liquid from the storage unit 120 to the liquid supply source 101. The control unit 60 stops the drive control of the supply mechanism 170 when the remaining amount RA reaches the limit value VL. This makes it possible to replace the liquid supply source 101.

The effect of this embodiment will be described.
(1) The control unit 60 drives the pressure mechanism 150 to pressurize the liquid in the storage unit 120 when the remaining amount RA of the liquid contained in the liquid supply source 101 reaches a predetermined value VP. Therefore, even when the remaining amount RA of the liquid contained in the liquid supply source 101 is further reduced and the liquid supply is changed to the storage unit 120, the fluctuation of the pressure for supplying the liquid can be reduced.

(2) The control unit 60 applies a pressure equal to or higher than the supply pressure to the liquid in the storage unit 120 when the remaining amount RA of the liquid stored in the liquid supply source 101 reaches the limit value VL. Since the liquid in the storage unit 120 is pressurized in advance, when the remaining amount RA in the liquid supply source 101 reaches the limit value VL and the liquid is supplied from the storage unit 120 to the liquid injection unit 41, the liquid is supplied. The supply pressure required for supply can be quickly pressurized.

(3) When the remaining amount RA of the liquid contained in the liquid supply source 101 reaches a predetermined value VP, the pressure applied to the liquid in the storage unit 120 is lower than the supply pressure. Therefore, the liquid in the storage unit 120 can be pressurized while supplying the liquid from the liquid supply source 101.

(4) When the remaining amount RA of the liquid contained in the liquid supply source 101 reaches a predetermined value VP, the pressure applied to the liquid in the storage unit 120 is higher than the adjusting pressure. Therefore, the hydraulic pressure adjusting mechanism 280 can stably adjust the pressure of the liquid supplied to the liquid injection unit 41.

(5) A second regulation valve 173 is provided in the liquid supply flow path 110 between the liquid supply source 101 and the storage unit 120. Therefore, even if the drive of the supply mechanism 170 is stopped, the pressure drop of the liquid supply flow path 110 between the second regulation valve 173 and the liquid injection unit 41 is suppressed. Therefore, the liquid supply source 101 can be replaced while supplying the liquid in the storage unit 120 to the liquid injection unit 41.

(6) The pressure mechanism 150 stops driving the storage pump 153 when the remaining amount RA is larger than the predetermined value VP, and drives the storage pump 153 when the remaining amount RA reaches the predetermined value VP to drive the liquid in the storage unit 120. Pressurize. Therefore, as compared with the case where the storage pump 153 is driven regardless of the remaining amount RA, for example, the driving time of the storage pump 153 can be shortened, and the durability required for the storage pump 153 can be lowered.

This embodiment can be modified and implemented as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
-As shown in FIG. 8, the storage portion 120 may have a structure in which a part of the wall thereof is formed by the flexible member 121. The storage unit 120 has a storage chamber 120A for storing a liquid. The pressure mechanism 150 connects the storage pump 153, the pressure adjustment chamber 158 located adjacent to the storage chamber 120A with the flexible member 121 interposed therebetween, and the storage pump 153 and the pressure adjustment chamber 158. And have.

When the storage pump 153 discharges gas from the pressure adjusting chamber 158, the flexible member 121 is displaced so as to increase the volume of the storage unit 120. In this way, the pressure mechanism 150 exerts a negative pressure in the reservoir 120 via the flexible member 121. When the storage pump 153 delivers gas to the pressure adjustment chamber 158, the flexible member 121 is displaced so as to reduce the volume of the storage unit 120. In this way, the pressure mechanism 150 pressurizes the inside of the storage unit 120.

-As shown in FIG. 9, the storage portion 120 does not have to be formed by the flexible member 121. The storage unit 120 may be configured as a rigid case, for example. The storage unit 120 has a storage chamber 120A for storing a liquid. The storage unit 120 stores an amount of liquid that is smaller than the maximum amount of liquid that can be stored. Therefore, the storage chamber 120A has a region in which a liquid exists and a region in which a gas exists.

The pressure mechanism 150 includes a storage pump 153 located outside the storage unit 120, and a pressure adjusting flow path 155 connecting the storage pump 153 and the storage chamber 120A. The pressure adjusting flow path 155 leads to the upper space in the storage chamber 120A. That is, the pressure adjusting flow path 155 communicates with the region where the gas exists in the storage chamber 120A. When the storage pump 153 discharges gas from the storage chamber 120A, a negative pressure acts in the storage unit 120. In this way, the pressure mechanism 150 applies a negative pressure to the inside of the storage unit 120 from the outside. When the pressure mechanism 150 sends gas to the storage chamber 120A, the inside of the storage unit 120 is pressurized.

The pressure mechanism 150 pressurizes the storage unit 120 at a pressure higher than the supply pressure to crush the bag body 122 while the remaining amount RA is larger than the predetermined value VP, so that the opposing inner surfaces of the bag body 122 are brought into contact with each other. It may be in a state. That is, the stored amount, which is the amount of liquid stored in the storage unit 120, may be minimized. By minimizing the amount of storage, the time for the liquid to stay in the storage unit 120 is shortened, and the possibility that the components in the liquid settle in the storage unit 120 can be reduced. When the remaining amount RA reaches the supply value, the pressure mechanism 150 releases the pressurization of the storage unit 120 or depressurizes the storage unit 120 to supply the liquid from the liquid supply source 101 to the storage unit 120 to reduce the storage amount. It may be maximized. The supply value may be larger than the predetermined value VP, for example, twice or three times the predetermined value VP. The control unit 60 drives the pressure mechanism 150 in the storage unit 120 when the remaining amount RA of the liquid stored in the liquid supply source 101 reaches a predetermined value VP while the liquid is stored in the storage unit 120. The liquid may be pressurized.

-The volumetric pump 171 may be composed of a tube pump. In this case, the supply mechanism 170 may be configured not to include the first regulation valve 172 and the second regulation valve 173.
When the remaining amount RA reaches the limit value VL, the control unit 60 may close the on-off valve 140 and regulate the flow of liquid from the storage unit 120 to the liquid supply source 101 by the on-off valve 140. .. That is, the on-off valve 140 may function as a regulating valve.

-When the remaining amount RA reaches a predetermined value VP, the pressure mechanism 150 may apply the same pressure as the adjusting pressure to the liquid in the storage unit 120. When the remaining amount RA reaches the limit value VL, the pressure mechanism 150 may apply a pressure smaller than the supply pressure to the liquid in the storage unit 120. The storage unit 120 may be provided at a position higher than the hydraulic pressure adjusting mechanism 280. The liquid in the storage unit 120 may be sent to the hydraulic pressure adjusting mechanism 280 by the water head.

The liquid injection device 10 may include a liquid level detection sensor that detects the position of the liquid level in the liquid supply source 101, and may acquire the remaining amount RA based on the detection result of the liquid level detection sensor. The liquid injection device 10 may acquire information indicating the remaining amount RA from the storage unit included in the liquid supply source 101. The control unit 60 has the remaining amount RA of the liquid stored in the liquid supply source 101 based on the information stored in the storage unit and the amount of liquid consumed by the liquid injection device 10 being equal to or less than a predetermined value VP or a limit. It may be determined whether or not the value is VL or less.

The bag body 122 may be formed of one flexible member 121.
-The medium M may be a metal film, a plastic film, a cloth, or the like.
The liquid ejected by the liquid injection unit 41 is not limited to ink, and may be, for example, a liquid material in which particles of a functional material are dispersed or mixed in the liquid. For example, the liquid injection unit 41 may inject a liquid material containing a material such as an electrode material or a pixel material used for manufacturing a liquid crystal display, an electroluminescence display, a surface emitting display, or the like in a dispersed or dissolved form.

The technical idea and its action and effect grasped from the above-described embodiments and modifications are described below.
(A) The liquid injection device includes a liquid injection unit that injects a liquid from a nozzle, a holding unit that is configured to attach and detach a liquid supply source that houses the liquid, and the liquid supply source that is attached to the holding unit. A liquid supply flow path configured to supply the liquid to the liquid injection section, and a liquid supply flow path that pressurizes the liquid in the liquid supply source to a supply pressure so that the liquid can be injected from the nozzle. A supply mechanism configured to supply the liquid toward the liquid injection unit via the liquid, and a storage unit provided in the liquid supply flow path and configured to store the liquid pressurized by the supply mechanism. A pressure mechanism configured to apply pressure to the liquid in the storage unit from the outside, and a pressure mechanism provided between the storage unit and the liquid injection unit in the liquid supply flow path are provided in the liquid injection unit. A hydraulic pressure adjusting mechanism that adjusts the pressure of the supplied liquid to an adjustment pressure that can be injected from the nozzle and is lower than the supply pressure, and the remaining amount of the liquid contained in the liquid supply source have become predetermined values. In some cases, it includes a control unit that drives the pressure mechanism to pressurize the liquid in the storage unit.

According to this configuration, the control unit drives the pressure mechanism to pressurize the liquid in the storage unit when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value. Therefore, even when the remaining amount of the liquid contained in the liquid supply source is further reduced and the supply of the liquid is changed to the storage portion, the fluctuation of the pressure for supplying the liquid can be reduced.

(B) In the liquid injection device, the control unit has the remaining amount at the predetermined value, and after driving the pressure mechanism to pressurize the liquid in the storage unit, the remaining amount becomes the predetermined value. When the lower limit value is reached, the pressure applied to the liquid in the reservoir by the pressure mechanism may be the same as or higher than the supply pressure.

According to this configuration, the control unit applies a pressure equal to or higher than the supply pressure to the liquid in the storage unit when the remaining amount of the liquid contained in the liquid supply source reaches the limit value. Since the liquid in the reservoir is pre-pressurized, the supply pressure required to supply the liquid when the remaining amount in the liquid supply source reaches the limit value and the liquid is supplied from the reservoir to the liquid injection section. Can be pressurized quickly.

(C) In the liquid injection device, when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the reservoir by the pressure mechanism may be lower than the supply pressure.
According to this configuration, when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value, the pressure applied to the liquid in the storage unit is lower than the supply pressure. Therefore, it is possible to pressurize the liquid in the storage unit while supplying the liquid from the liquid supply source.

(D) In the liquid injection device, when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the storage portion by the pressure mechanism may be higher than the adjustment pressure.
According to this configuration, when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value, the pressure applied to the liquid in the storage unit is higher than the adjusting pressure. Therefore, the hydraulic pressure adjusting mechanism can stably adjust the pressure of the liquid supplied to the liquid injection unit.

(E) The liquid injection device includes the control valve that regulates the flow of the liquid from the storage unit to the liquid supply source between the storage unit and the liquid supply source in the liquid supply flow path. The unit may stop the drive control of the supply mechanism when the remaining amount reaches a limit value smaller than the predetermined value.

According to this configuration, a regulating valve is provided in the liquid supply flow path between the liquid supply source and the storage unit. Therefore, even if the drive of the supply mechanism is stopped, the decrease in pressure in the liquid supply flow path between the regulation valve and the liquid injection portion is suppressed. Therefore, the liquid supply source can be exchanged while supplying the liquid in the storage unit to the liquid injection unit.

(F) The control method of the liquid injection device is a liquid supply flow path configured to inject the liquid from the nozzle and supply the liquid from the liquid supply source accommodating the liquid to the liquid injection unit. A supply mechanism configured to pressurize the liquid in the liquid supply source to a supply pressure and supply the liquid toward the liquid injection portion via the liquid supply flow path so that the liquid can be ejected from the nozzle. A storage unit provided in the liquid supply flow path and configured to store the liquid pressurized by the supply mechanism, and a storage unit configured to apply external pressure to the liquid in the storage unit. The pressure mechanism is provided between the storage unit and the liquid injection unit in the liquid supply flow path, and the pressure of the liquid supplied to the liquid injection unit can be injected from the nozzle and is lower than the supply pressure. It is a control method of a liquid injection device including a hydraulic pressure adjusting mechanism for adjusting to an adjusting pressure, and when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value, the pressure mechanism is used. Pressurize the liquid in the reservoir. According to this method, the same effect as that of the liquid injection device can be obtained.

(G) In the control method of the liquid injection device, the remaining amount becomes the predetermined value, and after the liquid in the storage portion is pressurized by the pressure mechanism, the remaining amount becomes a limit value smaller than the predetermined value. In this case, the pressure applied to the liquid in the reservoir by the pressure mechanism may be the same as or higher than the supply pressure. According to this method, the same effect as that of the liquid injection device can be obtained.

(H) In the control method of the liquid injection device, when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the reservoir by the pressure mechanism may be lower than the supply pressure. According to this method, the same effect as that of the liquid injection device can be obtained.

(I) In the control method of the liquid injection device, when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the reservoir by the pressure mechanism may be higher than the adjustment pressure. According to this method, the same effect as that of the liquid injection device can be obtained.

(J) In the control method of the liquid injection device, the liquid injection device regulates the flow of liquid from the storage unit to the liquid supply source between the storage unit and the liquid supply source in the liquid supply flow path. The drive control of the supply mechanism may be stopped when the remaining amount reaches a limit value smaller than the predetermined value. According to this method, the same effect as that of the liquid injection device can be obtained.

10 ... Liquid injection device, 11 ... Legs, 12 ... Housing, 13 ... Feeding part, 14 ... Guide part, 15 ... Winding part, 16 ... Tension applying mechanism, 17 ... Operation panel, 18 ... Cover, 20 ... Support Table, 30 ... Conveying unit, 31 ... 1st transport roller pair, 32 ... 2nd transport roller pair, 33 ... Conveying motor, 40 ... Printing unit, 41 ... Liquid injection unit, 42 ... Guide shaft, 43 ... Carriage, 44 ... Nozzle, 45 ... Carriage motor, 50 ... Discharge mechanism, 51 ... Cap, 52 ... Suction pump, 53 ... Waste liquid tank, 54 ... Regulator, 60 ... Control unit, 100 ... Liquid supply device, 101 ... Liquid supply source, 102 ... Holding Unit, 103 ... Remaining amount acquisition unit, 104 ... Prism, 105 ... Light emitting unit, 106 ... Light receiving unit, 110 ... Liquid supply flow path, 111 ... First liquid flow path, 112 ... Second liquid flow path, 120 ... Storage section , 120A ... Storage chamber, 121 ... Flexible member, 122 ... Bag body, 123 ... Connection body, 124 ... Introduction hole, 125 ... Outlet hole, 126 ... Connection path, 127 ... Introduction pipe, 128 ... Outlet pipe, 129 ... Adhesive part, 140 ... On-off valve, 150 ... Pressure mechanism, 151 ... Pressure chamber, 152 ... Container, 153 ... Storage pump, 154 ... Inner wall, 155 ... Pressure adjustment flow path, 156 ... Slit, 158 ... Pressure adjustment chamber, 170 ... Supply mechanism, 171 ... Volumetric pump, 172 ... First regulation valve, 173 ... Second regulation valve, 174 ... Flexible film, 175 ... Pump chamber, 176 ... Negative pressure chamber, 177 ... Pressure reducing part, 178 ... Pressing member, 187 ... Check valve, 210 ... 1st filter unit, 211 ... 1st filter, 212 ... 1st upstream filter chamber, 213 ... 1st downstream filter chamber, 220 ... 2nd filter unit, 221 ... 2nd filter, 222 ... 2nd upstream filter chamber, 223 ... 2nd downstream filter chamber, 230 ... 3rd filter unit, 231 ... 3rd filter, 232 ... 3rd upstream filter chamber, 233 ... 3rd downstream filter chamber, 250 ... Static mixer, 260 ... Liquid storage, 261 ... Pressurized chamber, 262 ... Elastic film, 263 ... First pressing member, 270 ... Degassing mechanism, 271 ... Degassing chamber, 272 ... Degassing membrane, 273 ... Exhaust chamber , 274 ... Exhaust passage, 275 ... Decompression pump, 280 ... Hydraulic pressure adjustment mechanism, 281 ... Communication hole, 282 ... Liquid chamber, 283 ... Valve body, 284 ... Pressure receiving member, 285 ... Flexible wall, 286 ... Second pressing member , 287 ... 3rd pressing member, 290 ... Valve opening mechanism, 291 ... Storage chamber, 292 ... Pressurized bag, 293 ... Pressurized flow path, 411 ... Individual liquid chamber, 412 ... Vibration plate, 413 ... Storage part, 414 ... Actuator -415 ... common liquid chamber, M ... medium, RA ... remaining amount, VL ... limit value, VP ... predetermined value.

Claims (10)

A liquid injection unit that injects liquid from a nozzle,
A holding unit configured to attach and detach a liquid supply source for accommodating the liquid,
A liquid supply flow path configured to supply the liquid from the liquid supply source mounted on the holding portion to the liquid injection portion.
A supply mechanism configured to pressurize the liquid in the liquid supply source so that the liquid can be ejected from the nozzle and supply the liquid toward the liquid injection portion through the liquid supply flow path.
A storage unit provided in the liquid supply flow path and configured to store the liquid pressurized by the supply mechanism, and a storage unit.
A pressure mechanism configured to apply pressure to the liquid in the reservoir from the outside,
The pressure of the liquid provided between the storage unit and the liquid injection unit in the liquid supply flow path and supplied to the liquid injection unit is adjusted to an adjustment pressure that can be injected from the nozzle and is lower than the supply pressure. Hydraulic pressure adjustment mechanism and
A control unit that drives the pressure mechanism to pressurize the liquid in the storage unit when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value.
A liquid injection device comprising. When the remaining amount reaches the predetermined value, and after driving the pressure mechanism to pressurize the liquid in the storage unit, the remaining amount reaches a limit value smaller than the predetermined value. The liquid injection device according to claim 1, wherein the pressure applied to the liquid in the storage unit by the pressure mechanism is set to the same pressure as or higher than the supply pressure. The liquid according to claim 1 or 2, wherein when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the reservoir by the pressure mechanism is lower than the supply pressure. Injection device. Any one of claims 1 to 3, wherein when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the storage portion by the pressure mechanism is higher than the adjusting pressure. The liquid injection device according to one item. A regulating valve for regulating the flow of the liquid from the storage unit to the liquid supply source is provided between the storage unit and the liquid supply source in the liquid supply flow path.
The control unit according to any one of claims 1 to 4, wherein the drive control of the supply mechanism is stopped when the remaining amount reaches a limit value smaller than the predetermined value. The liquid injection device described. A liquid injection unit that injects liquid from a nozzle,
A liquid supply flow path configured to supply the liquid from the liquid supply source accommodating the liquid to the liquid injection unit, and
A supply mechanism configured to pressurize the liquid in the liquid supply source so that the liquid can be ejected from the nozzle and supply the liquid toward the liquid injection portion through the liquid supply flow path.
A storage unit provided in the liquid supply flow path and configured to store the liquid pressurized by the supply mechanism, and a storage unit.
A pressure mechanism configured to apply pressure to the liquid in the reservoir from the outside,
The pressure of the liquid provided between the storage unit and the liquid injection unit in the liquid supply flow path and supplied to the liquid injection unit is adjusted to an adjustment pressure that can be injected from the nozzle and is lower than the supply pressure. Hydraulic pressure adjustment mechanism and
It is a control method of a liquid injection device provided with
A method for controlling a liquid injection device, which comprises pressurizing the liquid in the storage portion by the pressure mechanism when the remaining amount of the liquid contained in the liquid supply source reaches a predetermined value. When the remaining amount reaches the predetermined value, the liquid in the storage unit is pressurized by the pressure mechanism, and then the remaining amount reaches a limit value smaller than the predetermined value, the pressure mechanism in the storage unit. The method for controlling a liquid injection device according to claim 6, wherein the pressure applied to the liquid is set to the same pressure as or higher than the supply pressure. The liquid according to claim 6 or 7, wherein when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the reservoir by the pressure mechanism is lower than the supply pressure. How to control the injection device. Any of claims 6 to 8, wherein when the remaining amount reaches the predetermined value, the pressure applied to the liquid in the reservoir by the pressure mechanism is higher than the adjusting pressure. The method for controlling a liquid injection device according to item 1. The liquid injection device further includes a regulating valve that regulates the flow of liquid from the storage unit to the liquid supply source between the storage unit and the liquid supply source in the liquid supply flow path.
The liquid injection device according to any one of claims 6 to 9, wherein the drive control of the supply mechanism is stopped when the remaining amount reaches a limit value smaller than the predetermined value. Control method.