JP2005271266A - Manufacturing method and manufacturing equipment for droplet ejection head, droplet ejection head, and droplet ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning method and a cleaning device for removing foreign matter in an ink channel of a liquid ejection head, and to provide a droplet ejection head and a droplet ejector. <P>SOLUTION: The inside of the ink channel of the droplet ejection head 1 is decompressed by exhausting air, and cleaned by combining cleaning by a cleaning fluid with cleaning by nitrogen gas while maintaining this decompressed state. Cleaning by pure water and the cleaning by the nitrogen gas are performed in the state of being combined with each other. Additionally, the cleaning method and the cleaning device can repeat the cleaning by the cleaning fluid, the cleaning by the pure water and the cleaning by the nitrogen gas a plurality of times. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for cleaning an ink flow path of a droplet discharge head of a droplet discharge device, a manufacturing apparatus, a droplet discharge head, and a droplet discharge device.

  2. Description of the Related Art In recent years, various types of droplet discharge heads of a droplet discharge apparatus are known depending on a mechanism for generating (discharge) droplets. For example, there is a droplet discharge head of a type in which a heater is heated to boil a liquid and a droplet is discharged with a bubble pressure generated thereby. In addition, there is a droplet discharge head of a type that discharges droplets by expanding and contracting the volume of a pressure chamber by applying a voltage to a piezoelectric element attached to a pressure chamber that stores liquid. Further, there is a type in which droplets are discharged by changing the volume of a pressure chamber in which liquid is stored using electrostatic force. In any type of liquid droplet ejection head, liquid droplets are ejected from a nozzle by utilizing the pressure fluctuation in the pressure chamber.

  These types of droplet discharge heads have an ink flow path that connects an ink intake port through which ink is taken in and a nozzle through which ink is discharged. In addition, a minute ink supply port is formed in the ink flow path, and the ink supply port is provided with a hole having a size of several tens of μm. Also, in the manufacturing process of the droplet discharge head, foreign matter may be mixed in the ink flow path, and when this foreign matter is clogged in the ink flow path, the discharge failure occurs when the droplet discharge head discharges ink. There was a possibility of generating. As a result, the droplet discharge device may not be able to obtain high-precision print quality.

  For example, as disclosed in Patent Document 1, in order to eliminate such a phenomenon, a cleaning method for removing foreign matters in the ink flow path of the droplet discharge head has been proposed (for example, Patent Document 1). 1).

JP-A-6-8471

  However, this cleaning method is a method of removing foreign matter in the ink flow path of the droplet discharge head while discharging the cleaning solution, and has a structure in which a cleaning liquid discharge port is provided in a part of the droplet discharge head. In a small and high-density face inkjet type droplet discharge head, the nozzle holes are smaller than before, and the interval between adjacent nozzles is narrower, so part of the droplet discharge head There was no space to provide a cleaning liquid outlet. For this reason, there has been a demand for a cleaning method and a cleaning device in the ink flow path of the droplet discharge head that is small and can cope with high density.

  An object of the present invention is to provide a cleaning method, a cleaning device, a droplet discharge head, and a droplet discharge device that remove foreign matters in an ink flow path of the droplet discharge head.

  The droplet discharge head cleaning device of the present invention is a droplet discharge head cleaning device that cleans a droplet discharge head having an ink flow path that communicates an ink intake port through which ink is introduced and a nozzle from which the ink is discharged. In the ink flow path, the pressure in the ink flow path is reduced to a predetermined pressure by evacuating the ink flow path, and the pressure reduction section that maintains this pressure reduction state is connected to the ink intake port. A liquid supply unit that supplies liquid while pressurizing the liquid, a gas supply unit that supplies gas while applying pressure to the ink flow path, a liquid recovery unit that recovers the liquid while applying pressure, the decompression unit, A controller that controls the liquid supply unit, the gas supply unit, and the liquid recovery unit, wherein the control unit alternately repeats the liquid supply unit and the gas supply unit a plurality of times; and Previous And repeating a plurality of pressure reducing portion alternately.

  According to the present invention, the nozzle side is depressurized and liquid and gas (gas) are used, and these liquid and gas are alternately introduced into the ink flow path of the droplet discharge head while being pressurized. Foreign matter present in the ink flow path of the droplet discharge head can be reliably discharged from the nozzle hole to the outside. This makes it possible to form a droplet discharge head that can keep the ink flow path clean.

  According to another aspect of the invention, there is provided a method for manufacturing a droplet discharge head, comprising: an ink intake port through which an ink is taken in; and a nozzle through which the ink is discharged. Connecting, evacuating the ink flow path to a predetermined pressure, and maintaining the pressure-reduced state, supplying the liquid while pressurizing the liquid in the ink flow path, A first step of alternately repeating a cleaning step of cleaning with a liquid and a first cleaning step of supplying the gas in the ink flow path while pressurizing and cleaning with the gas; A second cleaning step for cleaning and a second step for alternately repeating the second pressure reducing step for reducing pressure at least once are provided.

  According to the present invention, by using liquid and gas (gas) and alternately introducing the liquid and gas into the ink flow path of the droplet discharge head while pressurizing the liquid and gas, Foreign matter present in the flow path can be more reliably discharged from the nozzle hole to the outside. This makes it possible to form a droplet discharge head that can keep the ink flow path cleaner.

  The method for manufacturing a droplet discharge head according to the present invention includes a rinsing step in which the liquid used in the cleaning step is a cleaning liquid, and the cleaning liquid in the ink flow path is washed away with the liquid after the second decompression step. It is desirable.

  According to the present invention, the inside of the ink flow path can be further cleaned by washing away the cleaning liquid. This makes it possible to form a droplet discharge head that can keep the ink flow path cleaner.

  In the method for manufacturing a droplet discharge head according to the present invention, the cycle process in which the first process and the second process are performed as one cycle is performed twice, and the liquid is discharged in the first cycle process and the second cycle process. It is desirable to be different.

  According to the present invention, since the cleaning liquid can be selected for each cycle, it is possible to provide a droplet discharge head that has a higher cleaning effect and can keep the ink flow path clean.

  In the method for manufacturing a droplet discharge head according to the present invention, it is desirable that the liquid in the first cycle step is a cleaning liquid and the liquid in the second cycle step is a rinse liquid.

  According to this invention, since the cleaning liquid and the rinsing liquid are used, it is possible to provide a liquid droplet ejection head that has a higher cleaning effect and can keep the ink flow path clean.

  In the method for manufacturing a droplet discharge head according to the present invention, the first step includes a recovery step of recovering the cleaning liquid after the cleaning in the cleaning step, and the second step is performed after the cleaning in the cleaning step. A draining step for draining the rinsing liquid, and the liquid discharge destination from the recovery container side to the draining side between the second step in the first cycle and the first step in the second cycle And a switching step of switching to the above.

  According to this invention, since there is a switching step, the cleaning liquid can be recovered, so that the cleaning liquid can be used any number of times and is economical. Therefore, it is possible to provide a method for manufacturing a droplet discharge head that is less costly.

  According to another aspect of the invention, there is provided a method for manufacturing a droplet discharge head, comprising: an ink intake port through which an ink is taken in; and a nozzle through which the ink is discharged. Connecting, evacuating the ink flow path to a predetermined pressure, and maintaining the pressure-reduced state, supplying the liquid while pressurizing the liquid in the ink flow path, A first step of alternately repeating a cleaning step of cleaning with a liquid and a first cleaning step of supplying a gas into the ink flow path while pressurizing and cleaning with the gas; and The cycle process in which the process and the second process are performed as one cycle is performed twice. The liquid is different in the first cycle process and the second cycle process, and the first process is performed after the cleaning in the cleaning process. Collect the cleaning solution A recovery step, wherein the first and second steps include a draining step of draining the rinse liquid after the cleaning in the cleaning step, the second step in the first cycle, and the first step A method of manufacturing a droplet discharge head, comprising: a switching step of switching a liquid discharge destination from a collection container side to a drainage side during a first step in two cycles.

  According to the present invention, the liquid droplet discharge head is introduced by using the liquid and the gas (gas) while reducing the pressure and introducing the liquid and the gas into the ink flow path of the liquid droplet discharge head while pressurizing the liquid and the gas. It is possible to reliably discharge the foreign matter or the cleaning liquid remaining in the ink flow path from the nozzle hole to the outside. Accordingly, it is possible to provide a droplet discharge head that can keep the inside of the ink flow path clean. In addition, the liquid used in the cleaning process can be recovered.

  The manufacturing method of the droplet discharge head of the present invention preferably includes a rough cleaning step before the cleaning step of cleaning with the liquid.

  According to the present invention, since the large foreign matter can be removed by cleaning the inside of the ink channel in advance, the inside of the ink channel can be cleaned more quickly. Therefore, it is possible to provide a droplet discharge head that is less likely to cause ink discharge defects.

  The droplet discharge head of the present invention is desirably manufactured by the above-described droplet discharge head manufacturing method.

  According to the present invention, since the foreign matter in the ink flow path can be removed and the inside of the ink flow path becomes clean, it is possible to provide a liquid droplet ejection head that is less likely to cause ink ejection problems.

  The droplet discharge device of the present invention is desirably a droplet discharge device including the above-described droplet discharge head.

  According to this invention, since the droplet discharge device includes the above-described droplet discharge head, it is possible to provide a droplet discharge device that can ensure high-precision print quality.

Hereinafter, embodiments of a droplet discharge head inspection method, a droplet discharge head inspection apparatus, a droplet discharge head, and a droplet discharge apparatus including the droplet discharge head according to the present invention will be described in detail with reference to the accompanying drawings. Explained.
(First embodiment)

  FIG. 1 is an exploded perspective view of a droplet discharge head 1 as a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the droplet discharge head 1.

  As shown in FIGS. 1 and 2, the droplet discharge head 1 is a face inkjet type that discharges ink droplets 23 from a nozzle 21 provided on the upper surface of a substrate, and is of an electrostatic drive type. The droplet discharge head 1 has a stacked structure in which a nozzle plate 4, a cavity plate 3, and a glass substrate 2 are stacked in this order.

  The cavity plate 3 is, for example, a silicon substrate. As shown in FIG. 1, the cavity plate 3 is formed with a recess 7 on the surface of which the bottom wall constitutes a pressure chamber 6 that functions as the vibration plate portion 5. ing.

  Etching is performed between the narrow groove 9 that constitutes the ink supply port 8 provided in the rear portion of the recess 7 and the recess 11 that constitutes the ink reservoir 10 for supplying ink to each pressure chamber 6. Is formed by. The lower surface of the cavity plate 3 is smoothed by mirror polishing and serves as a mounting portion for the glass substrate 2.

  As shown in FIGS. 1 and 2, in the nozzle plate 4 joined to the upper surface of the cavity plate 3 (substrate surface on the groove forming side), the wall portion defining the upper surface of the pressure chamber 6 is provided in each pressure chamber 6. A plurality of nozzles 21 communicating with each other are formed. The droplets 23 are discharged from the plurality of nozzles 21.

  By overlapping the nozzle plate 4 and the cavity plate 3 with each other, the pressure chamber 6, the ink supply port 8, and the ink reservoir 10 are partitioned between the nozzle plate 4 and the cavity plate 3. Here, a portion formed by the partitioned pressure chamber 6, ink supply port 8, and ink reservoir 10 is called a discharge chamber, and a space portion formed by the discharge chamber, the nozzle 21, and the ink intake port 31. Ink can be allowed to flow through, and this space portion is called an ink flow path (see FIG. 2).

FIG. 3 is a cross-sectional view of the ink flow path section 200.
Here, as shown in FIG. 3, the ink flow path unit 200 is configured by an ink flow path constituting member 230 and an ejection member 250 which is a part of the ink flow path cleaning device 300. The ink flow path constituting member 230 is constituted by the droplet discharge head 1 and the connection member 220.

  The connection member 220 includes a cover damper 201 provided with an ink inflow chamber 208, a flow path member 211 provided with an ink inflow passage 209, an ink inlet 203 through which ink flows into the damper chamber 202, and a damper 204. , A carriage 205 and a cover 207.

  A filter 206 is provided in the ink inflow chamber 208 of the flow path member 211 and has a function of removing foreign matter. The ink inflow path 209 communicates with the ink inlet 203 and the ink intake 31.

  In the connection member 220, the damper 204 is inserted between the flow path member 211 and the cover damper 201, and the flow path member 211 and the cover damper 201 are joined by an adhesive. The connecting member 220, the droplet discharge head 1, the carriage 205, and the cover 207 are joined together with an adhesive. The cover 207 is incorporated so as to cover a part of the droplet discharge head 1 on the nozzle 21 side (see FIG. 3).

  An ink intake port 31 is formed in a wall portion corresponding to the top surface of the ink reservoir 10 of the cavity plate 3 of the droplet discharge head 1. The ink intake port 31 communicates with the ink reservoir 10, the glass substrate 2, the flow path member 211, and the cover damper 201, and the connection pipe 210 and ink can flow from the outside to the outside of the cover damper 201. An ink inlet 203 is formed.

  The configuration of the connection pipe 210 and the discharge member 250 is shown in FIG. The ejection member 250 is connected to the ink flow path cleaning device 300. Here, the connection pipe 210 and the discharge member 250 are connected, and the inside of the ink flow path of the droplet discharge head 1 is cleaned by supplying liquid or gas (gas) from the outside. In the process of manufacturing the droplet discharge head 1, the droplet discharge head 1 in two types of states, that is, before the print inspection and after the print inspection may be cleaned.

On the other hand, the connection pipe 210 is connected to an ink supply source of the ink tank 101 (see FIG. 9) via a tube (not shown), and printing is possible when the droplet discharge device 100 is operated. . Ink can be supplied from the ink tank 101 to the ink reservoir 10 through the connection pipe 210, the connection member 220, and the ink intake port 31.

The discharge member 250 includes a discharge port 251 and an O-ring 252 (see FIG. 3).
When the discharge member 250 and the connection pipe 210 are connected and liquid or gas (gas) is supplied from the outside, an O-ring 252 is provided in the discharge member 250 so as not to leak from the connection portion. And airtightness is ensured (see FIG. 3).

  The ejection member 250 is mounted on the ink flow path cleaning device 300 shown in FIG. The discharge member 250 and the connection pipe 210 are connected, and the cleaning liquid, pure water, and N 2 gas are supplied from the discharge member 250 side to the ink flow path component 230 side. The cleaning liquid, pure water, and N 2 gas are supplied to the ink flow path component 230, pass through the ink inlet 203, the ink inlet 209, and the ink intake 31, and are discharged from the nozzle 21. The ink flow path of the droplet discharge head 1 is cleaned.

  FIG. 4 is a schematic view of a droplet discharge head cleaning device, and FIG. 5 is a piping system diagram.

  As shown in FIGS. 4 and 5, the ink flow path cleaning device 300 has a structure including a gantry 301, a casing 302, a removable drain pan 303, a work setting unit 304, a drainage recovery pad 305, and a work removal hand valve 306. It has become. Here, a housing 302 and a detachable drain pan 303 are fixed on the gantry 301, and a control unit 360 to be described later is mounted and fixed on the housing 302. Further, the work setting unit 304 is configured to be able to set the ink flow path constituting member 230. The drainage recovery pad 305 is disposed below the ink flow path constituting member 230 so that the drainage can be recovered. The workpiece removal hand valve 306 is used when the ink flow path constituting member 230 is removed from the workpiece setting unit 304, and is configured to be manually operated.

  The ink flow path cleaning apparatus 300 includes a decompression unit 310, a cleaning liquid supply unit 320, a cleaning liquid recovery unit 330, a pure water supply unit 340, a nitrogen gas supply unit 350, and a control unit 360.

  The decompression unit 310 includes a decompression pump 311, an air valve 312, and an air valve 313. The decompression pump 311 has a function of decompressing the ink flow path of the ink flow path constituting member 230 installed in the work setting unit 304. The decompression pump 311 can depressurize to 700 mHg. The air valve 312 is connected to the decompression pump 311 and receives a control signal from the control unit 360 to discharge the cleaning liquid to the outside or switch it to the cleaning liquid recovery tank 331. The air valve 313 is connected between the decompression pump 311 and the cleaning liquid recovery tank 331, and supplies the recovered cleaning liquid to the cleaning liquid recovery tank 331.

  The cleaning liquid supply unit 320 has a configuration in which a cleaning liquid supply tank 321, an air valve 322, a prefilter 323, a regulator 324, an air valve 325, a check valve 326, and an air valve 327 are connected in this order.

  The cleaning liquid supply tank 321 is a pressure type, and its pressure is 0.4 MPa. The volume of the cleaning liquid supply tank 321 is about 20L. The air valve 322 is connected between the cleaning liquid supply tank 321 and the prefilter 323, and is a valve for discharging the cleaning liquid to the outside. The prefilter 323 is provided to improve the cleanliness of the supplied cleaning liquid, and can remove foreign matters having a size of 5 μm or more. The regulator 324 adjusts the pressure when supplying the cleaning liquid from the cleaning liquid supply tank 321, and can arbitrarily set the supply pressure of the cleaning liquid. The air valve 325 is a valve that switches between supply and stop of the cleaning liquid, and operates in response to a control signal from the control unit 360. The check valve 326 is a check valve provided so that the cleaning liquid does not flow backward. The air valve 327 is a valve for supplying nitrogen gas to the cleaning liquid supply tank 321 from the outside.

  In the cleaning liquid recovery unit 330, a cleaning liquid recovery tank 331, an air valve 332, a transfer filter 333, and an air valve 334 are connected in this order. Further, the air valve 335 is branched from the cleaning liquid recovery tank 331 and connected thereto.

  The cleaning liquid recovery tank 331 is a pressure type, and its pressure is 0.4 MPa. The volume of the cleaning liquid recovery tank 331 is about 20L. The air valve 332 is connected between the cleaning liquid recovery tank 331 and the transfer filter 333 and is a valve for supplying the recovered cleaning liquid to the transfer filter 333 side. The transfer filter 333 is provided to improve the cleanliness of the recovered cleaning liquid, and can remove foreign matters having a size of 20 μm or more. The air valve 334 is connected between the transfer filter 333 and the cleaning liquid supply tank 321 and is a valve for supplying the recovered cleaning liquid to the cleaning liquid supply tank 321 side. The air valve 335 is a valve for supplying nitrogen gas to the cleaning liquid recovery tank 331 from the outside.

  The pure water supply unit 340 has a configuration in which a pre-filter 341, a regulator 342, an air valve 343, and a check valve 344 are connected in this order. The pure water supply unit 340 includes a pure water introduction unit (not shown) that can supply pure water from the outside.

  Pure water is supplied from the outside (not shown), and a pressure of 0.14 MPa is applied to the supplied pure water. The pure water passes through the prefilter 341 to the regulator 342 side. The prefilter 341 is provided to improve the cleanliness of pure water, and can remove foreign matters having a size of 5 μm or more. The regulator 342 sets the pressure when supplying pure water, and can set the supply pressure of pure water. The air valve 343 is a valve for switching between supply and stop of pure water. The check valve 344 is a check valve provided so that pure water does not flow backward.

  The nitrogen gas supply unit 350 has a configuration in which a pre-filter 351, a regulator 352, an air valve 353, a differential pressure gauge 354, and a final filter 355 are connected in this order. The nitrogen gas supply unit 350 includes a nitrogen gas introduction unit (not shown) that can supply nitrogen gas from the outside.

  Nitrogen gas is supplied from the outside (not shown), and a pressure of 0.4 MPa is applied to the supplied nitrogen gas. The nitrogen gas passes through the prefilter 351 to the regulator 352 side. The prefilter 351 is provided in order to improve the cleanliness of nitrogen gas, and can remove foreign matters having a size of 5 μm or more. The regulator 352 adjusts the pressure when supplying nitrogen gas, and can set the supply pressure of nitrogen gas. The air valve 353 is a valve capable of switching between supply and stop of nitrogen gas by a control signal of the control unit 360.

  A final filter 355 is provided to improve the cleanliness of the cleaning liquid, pure water, and nitrogen gas, and can remove foreign matters having a size of 5 μm or more. Further, the differential pressure gauge 354 is provided for checking the clogging of the final filter 355.

  Here, the ink flow path cleaning device 300 is controlled by the control unit 360. The control unit 360 includes an electrical box 361 and an operation panel 362. The operation panel 362 has a buzzer (not shown). The control unit 360 also has a function of controlling the decompression unit 310, the cleaning liquid supply unit 320, the cleaning liquid recovery unit 330, the pure water supply unit 340, and the nitrogen gas supply unit 350.

  The ink flow path cleaning apparatus 300 can supply power to the control unit 360 from the outside. The ink flow path cleaning device 300 is operated by operating the electrical box 361 and the operation panel 362.

  The configurations of the droplet discharge head 1, the manufacturing apparatus, and the droplet discharge device 100 in the first embodiment are as described above, and the configuration of the droplet discharge head 1 is described with reference to FIGS. 4 to 6 and 9. A cleaning method in the ink flow path and the droplet discharge device 100 will be described.

  As shown in FIG. 9, the droplet discharge device 100 controls the relative position between the recording sheet 104 and the droplet discharge head 1 by moving the carriage 102 while conveying the recording sheet 104 by the platen 103. By supplying ink from the ink tank 101 and ejecting ink droplets 23 from the droplet ejection head 1, arbitrary characters and images are printed on the recording paper 104.

  Here, FIG. 6 is a flowchart showing the cleaning process of the first embodiment. This cleaning step is for cleaning the ink flow path of the droplet discharge head 1 when no ink is in the ink flow path, and is performed after the droplet discharge head 1 is assembled.

  As shown in FIGS. 4 and 5, first, the ink flow path unit 200 is set in the work setting unit 304 provided in the ink flow path cleaning device 300. When the operation start button on the operation panel 362 is pressed, the discharge member 250 on the ink flow path cleaning device 300 side is lowered and connected to the ink connection pipe 210 of the ink flow path constituting member 230. Further, the discharge member 250 and the ink flow path are connected. The component member 230 is lowered in a connected state, and the nozzle 21 of the ink flow path component member 230 and the drainage recovery pad 305 are connected. By doing so, the ink intake port 31 and the nozzle 21 are sealed by the decompression pump 311 in an airtight state. Thereafter, the operation is started (S1 in FIG. 6).

  FIG. 6 shows steps from the start (start) to the end (end) of cleaning of the ink flow path of the droplet discharge head 1 by the ink flow path cleaning apparatus 300.

  The ink flow path component 230 is set in the ink flow path cleaning device 300. Here, when power is supplied from the outside and the ink flow path cleaning device 300 starts to operate, the ink connection pipe 210, the ejection member 250, and the drainage recovery pad 305 are connected. In step S1, the decompression pump 311 is activated (not shown). By operating the decompression pump 311, the atmosphere in the ejection chamber is exhausted, and the inside of the ink flow path of the droplet ejection head 1 is decompressed. This pressure reduction operation continues from the pressure reduction (S1) in the ink flow path cleaning shown in FIG. 6 to the pressure reduction stop (S15) in the flow path.

  In step S2, the inside of the ink flow path of the droplet discharge head 1 is depressurized, and from the discharge member 250 side to the inside of the ink flow path (discharge chamber) of the droplet discharge head 1 through the connection member 220 (not shown). ) Supply pure water. At this time, in response to a control signal from the control unit 360, the air valve 343 is operated for a time set by the timer to supply pure water, and the ink flow path of the droplet discharge head 1 is replaced with pure water. Then, the inside of the ink flow path is washed.

  In step S3, when the inside of the ink flow path is replaced with pure water, a control signal is received from the control unit 360, and the air valve 343 is operated to stop the supply of pure water.

  In step S4, nitrogen gas is supplied from the outside (not shown) into the ink flow path of the droplet discharge head 1 through the connection member 220 from the discharge member 250 side. At this time, in response to a control signal from the control unit 360, the air valve 353 is operated for a time set by the timer, and the pure water accumulated in the ink flow path is discharged with the nitrogen gas.

  In step S5, in response to a control signal from the control unit 360, the air valve 353 is activated to stop the supply of nitrogen gas.

  In step S6, in response to a control signal from the control unit 360, the air valve 343 is operated for a time set by a timer to supply pure water from the outside (not shown) into the ink flow path (discharge chamber). Then, the inside of the ink flow path is washed.

  In step S7, in response to a control signal from the control unit 360, the air valve 343 is operated to stop the supply of pure water.

  In step S8, upon receiving a control signal from the control unit 360, the air valve 353 is operated for a time set by the timer, and from the discharge member 250 side through the connection member 220 into the ink flow path of the droplet discharge head 1. Nitrogen gas is supplied from outside (not shown) to clean the inside of the ink flow path.

  In step S9, in response to a control signal from the control unit 360, the nitrogen gas is stopped and the inside of the ink flow path is decompressed.

  In step S10, the steps from step S6 to step S9 are repeated. The number of repetitions can be set from 1 to m times. If the ink flow path is insufficiently washed (in the case of NO), Steps S6 to S9 are repeated 1 to m times. Steps S6 to S10 may be omitted depending on circumstances.

  In step S11, the inside of the ink flow path is depressurized.

  In step S12, in response to a control signal from the control unit 360, the air valve 353 is operated for a time set by the timer to supply nitrogen gas and clean the inside of the ink flow path.

  In step S13, the supply of nitrogen gas is stopped and the inside of the ink flow path is depressurized. At this time, in response to a control signal from the control unit 360, the discharge member 250 is detached from the connection pipe 210.

Accordingly, in step S14, the atmosphere flows into the ink inflow path 209 through the ink inlet 203 of the connection member 220, and further, the atmosphere flows into the droplet discharge head 1 through the ink intake port 31, and the ink flow of the droplet discharge head 1 is increased. Dry the street.

  In step S15, the ink flow path cleaning device 300 stops, and the pressure reducing operation in the ink flow path is completed.

  FIG. 6 shows a cleaning method after assembling the droplet discharge head 1 in a combination of pure water and nitrogen gas. Here, as shown in FIG. 6, the supply of pure water starts from the pure water supply unit 340, the inside of the ink flow path of the droplet discharge head 1 is replaced with pure water, and the inside of the flow path is cleaned. When the replacement of the ink channel with pure water is completed, the supply of nitrogen gas starts from the nitrogen gas supply unit 350 and the pure water in the ink channel of the droplet discharge head 1 is discharged. Next, pure water is supplied again from the pure water supply unit 340 to wash the ink flow path of the droplet discharge head 1. Again, nitrogen gas is supplied from the nitrogen gas supply unit 350 to clean the ink flow path of the droplet discharge head 1. Here, since cleaning with pure water and nitrogen gas can be performed repeatedly, if the result of cleaning in the flow path is NO in step S10, the number of times of cleaning is set in advance (in this case) m can be set up to m times), and the ink channel can be repeatedly washed.

  Here, when the cleaning in the ink flow path is completed for the set m times, the pure water accumulated in the ink flow path is drained with nitrogen gas, the supply of the nitrogen gas is stopped, and the pressure in the ink flow path is reduced. . Next, the discharge member 250 is detached from the connection pipe 210. As a result, the atmosphere is introduced into the ink flow path, and the ink flow path of the droplet discharge head 1 is dried (S14). Thereafter, the pressure reduction in the ink flow path stops (S15).

In the first embodiment as described above, the following effects are obtained.
(1) By using a combination of a cleaning liquid and nitrogen gas, or a combination of pure water and nitrogen gas, the inside of the ink flow path of the droplet discharge head 1 can be cleaned while decompressing.
(2) Repeated cleaning by a combination of cleaning liquid and nitrogen gas and repeated cleaning by a combination of pure water and nitrogen gas can be performed.
(3) Accordingly, the foreign matter present in the ink flow path after the assembly of the droplet discharge head 1 can be more reliably discharged from the nozzle 21 to the outside. Accordingly, the ink flow path of the droplet discharge head 1 is cleaned. Therefore, it is possible to provide a droplet discharge head and a droplet discharge device that are capable of more stable printing quality. In addition, a cleaning method and a manufacturing apparatus of this type can be provided.
(4) Further, since the cleaning method and the manufacturing apparatus have a function of recovering the cleaning liquid, the droplet discharge head 1 can be cleaned with the recovered cleaning liquid. Therefore, it is economical.
(Second Embodiment)

7 and 8 are flowcharts showing the cleaning process of the second embodiment.
After the ink flow path unit 200 is completed, a print inspection is performed before the droplet discharge head 1 is assembled to the droplet discharge apparatus main body (inkjet printer), and cleaning is performed after the print inspection. At this time, the ink remains in the ink flow path of the ink flow path portion 200. It is necessary to remove this residual ink before shipment.

  In step S51, the pressure inside the ink flow path is reduced. This decompression method is the same as that in the above-described step S1. This decompression operation continues from the in-channel pressure reduction (S51) of the ink channel cleaning shown in FIGS. 7 and 8 to the in-channel decompression stop (S72).

  In step S52, in a state where the inside of the ink flow path is decompressed, the cleaning liquid supply tank 321 operates in response to a control signal from the control unit 360, and the inside of the ink flow path (from the ejection member 250 side) A cleaning liquid is supplied to the discharge chamber, and the inside of the ink flow path is replaced with the cleaning liquid for cleaning. The cleaning liquid used here was an alkaline cleaning liquid.

  In step S53, in response to a control signal from the control unit 360, the operation of the cleaning liquid supply tank 321 is stopped and the supply of the cleaning liquid is stopped.

  In step S54, nitrogen gas (not shown) is supplied from the outside to the ink flow path of the droplet discharge head 1 from the discharge member 250 side. At this time, in response to a control signal from the control unit 360, the air valve 353 is operated for a time set by the timer, and the cleaning liquid accumulated in the ink flow path is discharged with the nitrogen gas.

  In step S55, in response to a control signal from the control unit 360, the air valve 353 is operated to stop the supply of nitrogen gas.

  In step S56, in response to the control signal from the control unit 360, the operation of the cleaning liquid supply tank 321 is started, the cleaning liquid is supplied from the discharge member 250 into the ink flow path of the droplet discharge head 1, and the ink flow path Wash.

  In step S57, in response to a control signal from the control unit 360, the operation of the cleaning liquid supply tank 321 is stopped and the supply of the cleaning liquid is stopped.

  In step S58, nitrogen gas is supplied from the outside (not shown) into the ink flow path of the droplet discharge head 1 from the discharge member 250 side. At this time, in response to a control signal from the control unit 360, the air valve 353 is operated for a time set by the timer to clean the ink flow path.

  In step S59, in response to a control signal from the control unit 360, the air valve 353 is operated to stop the nitrogen gas, thereby depressurizing the ink flow path.

  In step S60, steps from step S56 to step S59 are repeated. The number of repetitions can be set from 1 to n times. If the ink flow path is insufficiently washed (in the case of NO), steps S56 to S59 are repeated 1 to n times. Steps S56 to S60 may be omitted in some cases.

  In step S61, the cleaning liquid in the ink flow path is recovered, and the recovered cleaning liquid is recovered in the cleaning liquid recovery tank 331. Steps S51 to S61 so far are A.

  Here, A and the following will be described. As shown in FIG. 8, steps S62 to S72 are performed, and the ink flow path cleaning device 300 stops its operation. In addition, since the process from this process S62 to S72 is the same as the process from S6 to process S15 shown in FIG. 6, description about these washing | cleaning methods is abbreviate | omitted.

  FIG. 7 and FIG. 8 show a cleaning method after the print inspection of the droplet discharge head 1 in the combination of the cleaning liquid, pure water, and nitrogen gas. Here, as shown in FIGS. 7 and 8, the supply of the cleaning liquid from the cleaning liquid supply unit 320 starts, and the inside of the ink flow path of the droplet discharge head 1 is cleaned. When the cleaning with the cleaning liquid is finished, the supply of nitrogen gas starts from the nitrogen gas supply unit 350, the cleaning liquid in the ink flow path of the droplet discharge head 1 is discharged, and the supply of nitrogen gas is stopped. The cleaning liquid is supplied again from the cleaning liquid supply unit 320 to clean the ink flow path of the droplet discharge head 1. Again, nitrogen gas is supplied from the nitrogen gas supply unit 350 to clean the ink flow path of the droplet discharge head 1.

  Here, since the cleaning with the cleaning liquid and the nitrogen gas can be performed repeatedly, if the result of cleaning in the flow path is NO in step S60, the number of times of cleaning is set in advance (in this case, n times). Can be repeatedly cleaned in the ink flow path.

  When the cleaning of the ink flow path using the cleaning liquid is completed, the process switches to a cleaning liquid recovery step (S61), and the cleaning liquid is recovered in the cleaning liquid recovery tank 331. Here, in step S61 and subsequent steps, steps S62 to S72 are cleaning steps using pure water and nitrogen gas, and are the same as the cleaning methods from step S6 to step S15 shown in FIG. The detailed explanation is omitted.

  Accordingly, by adopting these cleaning methods, the presence of foreign matter in the ink flow path of the droplet discharge head 1 is reduced, and the droplet discharge head 1 is cleaned.

In the second embodiment as described above, the following effects can be obtained in addition to the effects obtained in the first embodiment.
(5) Since cleaning can be performed after the print inspection of the droplet discharge head 1, residual ink remaining in the ink flow path of the ink flow path section 200 can be removed. Therefore, it is possible to provide a droplet discharge head and a droplet discharge device capable of stable printing quality by washing before shipping the product.

  The present invention is not limited to the first and second embodiments described above, but includes modifications and improvements as long as the object of the present invention can be achieved. A modification is shown below.

  (Modification) In the embodiment, the cleaning liquid, pure water, and nitrogen gas are supplied from the ink flow path constituting member 230 side through the ink intake port 31 of the droplet discharge head 1 to supply the nozzle 21 of the droplet discharge head 1. Although it arrange | positions so that it may discharge | emit to the side, this invention does not stick to this. For example, cleaning liquid, pure water, and nitrogen gas are supplied from the nozzle 21 side of the droplet discharge head 1, pass through the ink intake 31 of the droplet discharge head 1, and are discharged to the ink flow path component 230 side. You may arrange.

  By doing so, the size of the hole of the ink intake port 31 is larger than the size of the hole of the nozzle 21, so that foreign matters are likely to come out from the ink flow path of the droplet discharge head 1. Therefore, the inside of the ink flow path of the droplet discharge head 1 can be cleaned more cleanly.

1 is an exploded perspective view of a droplet discharge head 1 as an embodiment of the present invention. FIG. 3 is a cross-sectional view of the droplet discharge head 1. FIG. 6 is a cross-sectional view of the ink flow path section 200. Schematic of a droplet discharge head cleaning device. The piping system diagram of a droplet discharge head cleaning device. The flowchart which shows the washing | cleaning process of 1st Embodiment. The flowchart which shows the washing | cleaning process of 2nd Embodiment. The flowchart which shows the washing | cleaning process of 2nd Embodiment. A droplet discharge device equipped with a droplet discharge head 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Droplet discharge head, 100 ... Droplet discharge apparatus, 300 ... Ink flow path cleaning apparatus, 310 ... Decompression unit, 311 ... Decompression pump, 320 ... Cleaning liquid supply part, 330 ... Cleaning liquid collection part, 340 ... Pure water supply part 350 ... nitrogen gas supply unit, 360 ... control unit.

Claims (10)

In a droplet discharge head cleaning device for cleaning a droplet discharge head having an ink flow path that communicates an ink intake port through which ink is introduced and a nozzle from which the ink is discharged,
A pressure reducing unit connected to the nozzle and depressurizing to a predetermined pressure by exhausting the inside of the ink flow path, and maintaining this reduced pressure state;
A liquid supply unit connected to the ink intake port and supplying the liquid while pressurizing the liquid in the ink flow path;
A gas supply unit configured to supply gas while pressurizing the ink flow path;
A liquid recovery unit for recovering the liquid;
A controller that controls the decompression unit, the liquid supply unit, the gas supply unit, and the liquid recovery unit;
The control unit repeats the liquid supply unit and the gas supply unit alternately a plurality of times,
A droplet discharge head cleaning apparatus, wherein the gas supply unit and the decompression unit are alternately repeated a plurality of times. In a manufacturing method of a droplet discharge head having an ink flow path that communicates an ink intake port through which ink is taken in and a nozzle from which the ink is discharged,
A first depressurization step of connecting to the nozzle and depressurizing to a predetermined pressure by exhausting the inside of the ink flow path, and maintaining this depressurized state;
A cleaning step of supplying liquid while pressurizing the ink flow path and cleaning with the liquid;
A first step of alternately supplying a plurality of times to the first cleaning step of supplying the gas into the ink flow path while pressurizing and cleaning with the gas;
A second cleaning step of cleaning with the gas;
A method of manufacturing a droplet discharge head, comprising: a second step of alternately repeating the second pressure reduction step of reducing the pressure at least once.   3. The method of manufacturing a liquid droplet ejection head according to claim 2, wherein the liquid used in the cleaning step is a cleaning liquid, and a rinsing step of rinsing the cleaning liquid in the ink flow path with the liquid after the second pressure reducing step. A method of manufacturing a droplet discharge head, comprising: In the droplet discharge head manufacturing method according to claim 2 or claim 3,
A liquid droplet ejection head manufacturing method, wherein a cycle process in which the first process and the second process are performed as one cycle is performed twice, and the liquid is different between the first cycle process and the second cycle process. Method.   5. The liquid droplet ejection head manufacturing method according to claim 2, wherein the liquid in the first cycle step is a cleaning liquid, and the liquid in the second cycle step is a rinse liquid. A manufacturing method of a droplet discharge head characterized by the above. In the droplet discharge head manufacturing method according to any one of claims 2 to 5,
The first step includes a recovery step of recovering the cleaning liquid after cleaning in the cleaning step,
The second step includes a draining step of draining the rinse liquid after the cleaning in the cleaning step, and between the second step in the first cycle and the first step in the second cycle. And a switching step of switching the liquid discharge destination from the collection container side to the liquid discharge side. In a manufacturing method of a droplet discharge head having an ink flow path that communicates an ink intake port through which ink is taken in and a nozzle from which the ink is discharged,
A first depressurization step of connecting to the nozzle and depressurizing to a predetermined pressure by exhausting the inside of the ink flow path, and maintaining this depressurized state;
A cleaning step of supplying liquid while pressurizing the ink flow path and cleaning with the liquid;
A first step of alternately supplying a plurality of times to the first cleaning step of supplying the gas into the ink flow path while pressurizing and cleaning with the gas;
The cycle process with the first process and the second process as one cycle is performed twice, and the liquid is different between the first cycle process and the second cycle process,
The first step includes a recovery step of recovering the cleaning liquid after cleaning in the cleaning step,
The first and second steps include a draining step of draining the rinse liquid after cleaning in the cleaning step, the second step in the first cycle, and the first step in the second cycle. And a switching step of switching a liquid discharge destination from the collection container side to the drainage side during the step.   8. The method of manufacturing a droplet discharge head according to claim 2, further comprising a rough cleaning step before the cleaning step of cleaning with the liquid. Production method.   A droplet discharge head manufactured by the method for manufacturing a droplet discharge head according to any one of claims 2 to 8. A droplet discharge apparatus comprising the droplet discharge head according to claim 9.

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