JP2020185755A - Printing apparatus and ink filling method - Google Patents

Abstract

To prevent the occurrence of poor ejection of ink to thereby improve image quality.SOLUTION: A printing apparatus comprises: a recording head Hdi; an ink storage portion; a spare liquid storage portion; an ink flow path arranged between the ink storage portion and the recording head; a spare liquid supply processing unit Pr4 that supplies spare liquid to a pour-in port formed in the ink flow path to fill a filling-flow path with spare liquid; an air introduction processing unit Pr5 that introduces air through an introduction port formed in the ink flow path and discharges the spare liquid through the filling-flow path; and an ink supply processing unit Pr6 that fills ink into the filling-flow path through which the spare liquid has been discharge. Mixing of the spare liquid in the ink can be inhibited since the ink is filled into the filling-flow path through which the spare liquid has been discharged.SELECTED DRAWING: Figure 3

Description

The present invention relates to a printing apparatus and an ink filling method.

Conventionally, in printing devices such as printers, copiers, facsimiles, and multifunction devices, for example, in an inkjet printer, a carriage is moved along a rail, ink is ejected from a recording head mounted on the carriage, and the ink adheres to a recording medium. Images such as characters and images are formed by being made to print, and printing is performed. Therefore, an ink tank is arranged in the inkjet printer, and the ink in the ink tank is supplied to the recording head.

By the way, when the use of the inkjet printer is started, the ink flow path for supplying the ink to the recording head is not filled with ink and contains air or a preservative liquid.

When the ink tank is attached to the inkjet printer and the recording head is driven in this state, the air remaining in the ink flow path, the preservative liquid, and the like are mixed in the ink, resulting in poor ink ejection.

Further, when the dissolved oxygen is contained in the ink, bubbles are generated by the dissolved oxygen, and the ink ejection failure occurs.

As a result, missing dots occur in the image, and the image quality deteriorates.

Therefore, a degassing module for removing dissolved oxygen in the ink is arranged in the ink flow path, and a preliminary liquid composed of an organic solvent or the like that has been degassed in advance is applied to the ink flow path before printing is started. There is provided an inkjet printer in which the recording head is driven after being filled with ink and replacing the preliminary liquid with ink (see, for example, Patent Document 1).

Japanese Patent No. 5186967

However, in the conventional inkjet printer, the preliminary liquid filled in the ink flow path is replaced with the ink without being discharged to the outside, so that the preliminary liquid is mixed with the ink, resulting in poor ink ejection and image quality. Will decrease.

That is, before the recording by the recording head is started, all the preliminary liquid filled in the ink flow path needs to be discharged to the outside, but the preliminary liquid is replaced while remaining in the ink flow path, so that it is a reserve. It is not possible to prevent the liquid from mixing with the ink.

It is possible to prevent the ink ejection failure from occurring by completely replacing the preliminary liquid with ink, but in this case, the amount of ink used until the ink can be ejected from the recording head. Will increase.

An object of the present invention is to provide a printing apparatus and an ink filling method capable of solving the problems of the conventional inkjet printer and improving the image quality without causing poor ink ejection.

Therefore, in the printing apparatus of the present invention, the ink disposed between the recording head, the ink accommodating portion for accommodating the ink, the preparatory liquid accommodating portion accommodating the preliminary liquid, and the ink accommodating portion and the recording head. From the flow path, the preliminary liquid supply processing unit that supplies the preliminary liquid to the injection port formed in the ink flow path and fills the predetermined filling flow path with the preliminary liquid, and the introduction port formed in the ink flow path. It has an air introduction processing unit that introduces air and discharges the preliminary liquid from the filling flow path, and an ink supply processing unit that fills the filling flow path with ink after the preliminary liquid is discharged.

According to the present invention, in the printing apparatus, the ink disposed between the recording head, the ink accommodating portion for accommodating ink, the preparatory liquid accommodating portion accommodating the preliminary liquid, and the ink accommodating portion and the recording head. From the flow path, the preliminary liquid supply processing unit that supplies the preliminary liquid to the injection port formed in the ink flow path and fills the predetermined filling flow path with the preliminary liquid, and the introduction port formed in the ink flow path. It has an air introduction processing unit that introduces air and discharges the preliminary liquid from the filling flow path, and an ink supply processing unit that fills the filling flow path with ink after the preliminary liquid is discharged.

In this case, since the ink is filled in the filling flow path after the preliminary liquid is discharged, it is possible to prevent the preliminary liquid from being mixed with the ink.

Therefore, since ink ejection failure does not occur, the image quality can be improved. Further, since it is not necessary to replace the preliminary liquid with ink, the amount of ink used until the ink can be ejected from the recording head can be reduced.

Further, when the preliminary liquid is discharged from the filling flow path, the wall in the filling flow path becomes wet, so that the ink can be smoothly filled to every corner of the filling flow path.

Therefore, the amount of ink used until the ink can be ejected from the recording head can be further reduced.

It is the schematic of the ink supply system in the 1st Embodiment of this invention. It is a perspective view of the inkjet printer in the 1st Embodiment of this invention. It is a control block diagram of the inkjet printer in the 1st Embodiment of this invention. It is a 1st flowchart which shows the operation of the control part in 1st Embodiment of this invention. It is a 2nd flowchart which shows the operation of the control part in 1st Embodiment of this invention. It is a 1st flowchart which shows the operation of the control part in 2nd Embodiment of this invention. It is a 2nd flowchart which shows the operation of the control part in 2nd Embodiment of this invention. It is a 3rd flowchart which shows the operation of the control part in the 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this case, an inkjet printer as a printing device will be described.

FIG. 2 is a perspective view of an inkjet printer according to the first embodiment of the present invention.

In the figure, 10 is an inkjet printer, Fr is a frame, and the frame Fr is a receiving plate BP arranged so as to extend from the left end to the right end when the inkjet printer 10 is viewed from the front side (front side in the figure). The rail 15 is arranged so as to extend along the receiving plate BP, and the carriage 17 is movably arranged along the rail 15 in the left-right direction, that is, in the main scanning direction.

In the carriage 17, one or more, in the present embodiment, a plurality of recording heads Hdi (i = 1, 2, ...,) (FIG. 1) described later are nozzles including a plurality of nozzles (not shown). It is mounted with the surface facing downward.

Further, a pulley 18 on the drive side and a pulley 19 on the driven side on the right end side of the frame Fr are rotatably arranged on the left end side of the frame Fr, and the pulley 18 on the drive side and the pulley 19 on the driven side are arranged. An endless belt 21 is stretched so as to travel between them, and the carriage 17 is attached to a predetermined position of the endless belt 21. Then, the carriage motor 22 as a drive unit for moving the carriage is connected to the pulley 18 on the drive side.

Therefore, by driving the carriage motor 22 and running the endless belt 21, the carriage 17 can be moved in the main scanning direction, and each recording head Hdi can be moved in the main scanning direction. At this time, ink of each color is ejected from each recording head Hdi, and the ink is adhered to a recording medium (not shown) conveyed in a direction orthogonal to the moving direction of the carriage 17, that is, in a sub-scanning direction. Images such as characters and images are formed on the recording medium and printed. In addition to paper, a resin film such as vinyl chloride or PET can be used as the recording medium.

A linear scale 23 is arranged along the rail 15, and the scale of the linear scale 23 is read by an encoder 35 (FIG. 3) arranged on the carriage 17 described later, and based on the sensor output of the encoder 35. The position of the carriage 17 is detected. Further, the speed of the carriage 17 is calculated based on the change in the position of the carriage 17.

Further, a platen 25 having a plate-like shape and supporting a recording medium is disposed in a predetermined region on the receiving plate BP, and a recording medium conveyed on the platen 25 is placed below the platen 25. An air suction mechanism (not shown) for attracting to the platen 25 by negative pressure is provided.

A pre-guide (not shown) as a medium rear guide is arranged on the rear side of the platen 25 (on the upstream side of the platen 25 in the transport direction of the recording medium). The pre-guide guides a recording medium that is unwound and conveyed from a feeding roll (not shown) to the platen 25. Therefore, a transport roller pair 30 as a transport member is rotatably arranged between the pre-guide and the platen 25 in the transport direction of the recording medium.

The transport roller pair 30 is a transport roller 31 as a first roller that extends along the platen 25 and is rotatably arranged, and is rotatably arranged above the transport roller 31 and is a recording medium. Is composed of a plurality of pinch rollers 32 as a second roller for pressing the transfer roller 31. When the transport motor 34 as a drive unit for transport, which will be described later, is driven and the transport roller 31 is rotated, the pinch roller 32 is rotated in a rotating manner, whereby the recording medium is the transport roller 31 and the pinch roller 32. It is unwound from the feeding roll in a state of being sandwiched between the above, conveyed along the pre-guide, and sent onto the platen 25. Then, the recording medium flatly supported by the platen 25 and the nozzle surface of the recording head Hdi are opposed to each other, ink is ejected from the recording head Hdi, and the ink adheres to the recording medium.

When printing is performed by the single-pass method, the transport motor 34 is driven to transport the recording medium by a predetermined distance, the transport motor 34 is stopped, and the carriage 17 is moved in one direction in that state. By ejecting ink from the recording head Hdi, one scan is performed and an image for one line is formed. When one scan is completed, the transport motor 34 is driven again to transport the recording medium by a predetermined distance, then the transport motor 34 is stopped, the carriage 17 is moved in the other direction in that state, and the ink is ink from the recording head Hdi. Is discharged, one scan is performed, and one line of images is formed. By repeating this operation, an image is formed on the recording medium.

Further, when printing is performed by the multipath method, the distance for carrying the recording medium is shorter than the nozzle row of the recording head Hdi, and an image for one line is formed by performing a plurality of scans.

On the front side of the frame Fr, an after-guide 33 as a medium forward guide portion for guiding the recording medium after printing is performed is arranged. The after-guide 33 has a curved shape in order to guide the recording medium horizontally ejected from the platen 25 downward.

In the present embodiment, heaters (not shown) as heating bodies are arranged in each of the pre-guide, platen 25, and after-guide 33, and by energizing each heater, the pre-guide, platen 25, and after-guide 33 are energized. The recording medium to be conveyed is heated to an appropriate temperature, and the drying of the adhered ink is promoted.

By the way, in the present embodiment, ink is ejected by each recording head Hdi, that is, recording is performed while the carriage 17 is moved on the platen 25 along the rail 15, and the carriage 17 is the platen. When the 25 is placed at the right end or the left end on the receiving plate BP on which the 25 is not arranged, recording by each recording head Hdi is not performed.

Therefore, in the present embodiment, the right end on the receiving plate BP is set to the home position for aligning the origin of the position of the carriage 17, and the left end on the receiving plate BP retracts the carriage 17 from the platen 25. At the same time, it is set to the retracted position for turning back.

Then, at the home position, a cap unit 43 is arranged so as to face each recording head Hdi. When the inkjet printer 10 is not used for a long time, the cap unit 43 covers the nozzle surface of the recording head Hdi with a cap and periodically sucks ink from the recording head Hdi to increase the viscosity of the ink in the nozzle. This prevents the nozzle from being clogged and dust from adhering to the nozzle.

At the retracted position, a wipe unit 44 for cleaning the nozzle surface is arranged so as to face each recording head Hdi and hold the nozzle in a good state.

In addition, reference numeral 20 denotes an ink supply system for supplying ink of each color to each recording head Hdi from a plurality of ink tanks Iti (i = 1, 2, ...) As an ink accommodating portion, which will be described later.

Next, the ink supply system 20 will be described.

FIG. 1 is a schematic view of an ink supply system according to the first embodiment of the present invention. In the figure, the ink supply system 20 for each color of ink is represented by one schematic diagram for convenience.

In the figure, 20 is an ink supply system, Hdi is a recording head, Iti is an ink tank for accommodating ink, and Mti (i = 1, 2, ...) Is arranged corresponding to the ink tank Iti to provide a reserve liquid. The reserve liquid tank Rmi (i = 1, 2, ...) As the reserve liquid accommodating portion for accommodating is arranged between the ink tank Iti and the recording head Hdi, and is an ink for supplying ink to the recording head Hdi. The flow path R1 is a branch flow path formed by branching from the ink flow path Rmi and opening to the atmosphere, and R2 is branched from the ink flow path Rmi and serves as a waste liquid accommodating portion. It is a branch flow path formed by connecting to the waste liquid bottle 49.

A switching valve v11, an air introduction valve v12, a liquid feed pump 45, a degassing module 47 as a degassing device, and a waste liquid valve v13 are arranged from the upstream side to the downstream side in the ink flow path Rmi, and the degassing module 47 The vacuum pump 48 is connected to the waste liquid valve v13, and the waste liquid bottle 49 is connected to the waste liquid valve v13.

The switching valve v11 is arranged in the vicinity of the ink tank Iti in the ink flow path Rmi, and forms an injection port for injecting the preliminary liquid into the ink flow path Rmi. Therefore, the switching valve v11 is placed in the first and second switching positions, and at the first switching position, the injection port is closed, and the supply flow path K1 of the ink tank Iti and the portion downstream of the ink flow path Rmi. At the second switching position, the injection port is opened to communicate the supply flow path K2 of the preliminary liquid tank Mti and the downstream portion of the ink flow path Rmi.

The air introduction valve v12 forms an introduction port for introducing air into the ink flow path Rmi. Therefore, the air introduction valve v12 is placed at the first and second switching positions, and at the first switching position, the introduction port is closed and the upstream portion and the downstream portion of the ink flow path Rmi are communicated with each other. Then, at the second switching position, the introduction port is opened so that the branch flow path R1 and the downstream portion of the ink flow path Rmi are communicated with each other.

The liquid feed pump 45 supplies ink or preliminary liquid to the recording head Hdi, the waste liquid bottle 49, and the like.

The degassing module 47 removes dissolved gas such as dissolved oxygen from the ink to perform degassing. Therefore, the vacuum pump 48 is connected to the degassing module 47.

As the degassing module 47, for example, a hollow fiber degassing module such as an external reflux type or an internal reflux type is used. In the external recirculation type hollow fiber degassing module, ink is flowed through a flow path formed on the outside of a large number of hollow fiber membranes, and the inside of the hollow fiber membrane is depressurized by the vacuum pump 48 to create a vacuum. It is possible to remove a large amount of dissolved gas such as dissolved oxygen while reducing the pressure loss during deaeration. The hollow fiber membrane is formed of a hollow fiber (straw-shaped) made of a resin material that allows gas to pass through and does not allow liquid to pass through. As the resin material, a polyolefin-based resin such as polypropylene or poly-4-methylpentene 1 or a fluorine-based resin such as polytetrafluoroethylene or vinylidene fluoride is used.

The waste liquid bottle 49 is connected to the waste liquid valve v13 via the branch flow path R2, and receives and stores the ink or the preliminary liquid as the waste liquid.

The waste liquid valve v13 forms a waste liquid port for discharging ink or preliminary liquid in the ink flow path Rmi. Therefore, the waste liquid valve v13 is placed at the first and second switching positions, and at the first switching position, the waste liquid port is closed and the upstream portion and the downstream portion of the ink flow path Rmi are communicated with each other. , At the second switching position, the waste liquid port is opened so that the upstream portion of the ink flow path Rmi and the branch flow path R2 are communicated with each other.

As the ink contained in the ink tank Iti, a water-based ink containing water, a water-soluble organic solvent, a pigment, or the like is used. Since water-based ink tends to generate bubbles due to dissolved gas such as dissolved oxygen, it is highly necessary to remove the dissolved gas such as dissolved oxygen by the degassing module 47.

Further, as the preliminary liquid contained in the preliminary liquid tank Mti, an organic solvent having a low viscosity contained in the ink is used, and when an aqueous ink is used, water can also be used.

In the ink supply system 20, the first filling flow path Ch1 as a predetermined filling flow path is formed by the flow path composed of the ink flow path Rmi and the recording head Hdi, and the air introduction valve v12 in the ink flow path Rmi. A first air introduction flow path Ar1 is formed by a flow path composed of a portion on the downstream side and a recording head Hdi, and a portion on the upstream side of the waste liquid valve v13 in the ink flow path Rmi serves as a predetermined filling flow path. The filling flow path Ch2 of 2 is formed, and the second air introduction flow path Ar2 is formed by a portion of the ink flow path Rmi on the downstream side of the air introduction valve v12 and on the upstream side of the waste liquid valve v13.

Since air may enter the ink flow path Rmi from the resin piping portion, the joint portion, etc. existing in the ink flow path Rmi, the degassing module 47 is arranged as close to the recording head Hdi as possible. However, the degassing module 47 can be arranged at an arbitrary position between the ink tank Iti and the recording head Hdi.

As the switching valve v11, the air introduction valve v12, and the waste liquid valve v13, an electrically driven solenoid valve is used, but a manual valve can also be used.

The waste liquid valve v13 is removed as much as possible so that the ink in the ink flow path Rmi between the waste liquid valve v13 and the recording head Hdi is not wasted when the degassing module 47 is replaced. Although it is arranged in the vicinity of the air module 47, it can be arranged at any place between the degassing module 47 and the recording head Hdi.

The reserve liquid tank Mti is arranged for each ink flow path Rmi, but one reserve liquid tank common to each ink flow path Rmi can be arranged.

Further, among the ink tank Iti, the reserve liquid tank Mti, the switching valve v11, the air introduction valve v12, the liquid feed pump 45, the degassing module 47, the vacuum pump 48, the waste liquid valve v13, the waste liquid bottle 49, etc. in the ink supply system 20. A predetermined member can be mounted on the carriage 17 (FIG. 2), but in that case, not only the carriage 17 becomes heavy but also the inkjet printer 10 becomes large, so that only the recording head Hdi is used in the present embodiment. Is mounted on the carriage 17.

Next, the control device of the ink jet printer 10 will be described.

FIG. 3 is a control block diagram of an inkjet printer according to the first embodiment of the present invention.

In the figure, 10 is an inkjet printer, 35 is an encoder, 55 is an operation panel, 57 is a sensor group, 80 is a control unit that controls the entire sequence of the inkjet printer 10 and controls printing, and 81 is a non-volatile memory. A ROM as a first storage device, 82 is a RAM as a second storage device composed of a volatile memory, and 83 is an interface control unit that receives print data and control commands from a host computer (not shown) as a higher-level device.

The encoder 35 reads the scale of the linear scale 23 in order to detect the position of the carriage 17 (FIG. 2).

The operation panel 55 is an operation (not shown) including a display unit (not shown) including an LED screen or the like for displaying the state of the inkjet printer 10, and switches, keys, or the like for the operator to input an instruction to the inkjet printer 10. It has a part. When the operation panel 55 is formed by a touch panel, the operation panel 55 functions not only as a display unit but also as an operation unit.

The sensor group 57 includes various sensors for monitoring the operating state of the inkjet printer 10, for example, a medium position detection sensor that detects the position of a recording medium, a temperature sensor that detects the printing environment in which the inkjet printer 10 is placed, and a temperature sensor. It consists of a humidity sensor and the like.

The control unit 80 includes a CPU, an input / output port, a timer, and the like as arithmetic units (not shown), and performs various processes based on a program recorded in the ROM 81. In addition to the program, various set values are recorded in the ROM 81. Further, in the RAM 82, various control data are temporarily recorded in addition to the image data for normal printing, which is generated based on the print data. The RAM 82 is used as a working memory when the CPU performs an operation.

Further, the control unit 80 includes a recording processing unit Pr1, a transport processing unit Pr2, a carriage drive processing unit Pr3, a preliminary liquid supply processing unit Pr4, an air introduction processing unit Pr5, an ink supply processing unit Pr6, and the like.

The recording processing unit Pr1 generates image data based on the print data and control commands sent from the host computer, and drives the recording head Hdi via the head driving unit Dr1 to form an image on the recording medium.

The recording head Hdi is provided with a piezo element (not shown) as a driving element for each nozzle, and when a predetermined voltage is applied between the electrodes arranged at both ends of the piezo element, the voltage is increased. The piezo element is driven and expanded and contracted, thereby deforming the side wall of the ink ejection path that sends ink to each of the nozzles. Then, the cross-sectional area of the ink ejection path changes according to the expansion and contraction of the piezo element, so that the amount of ink corresponding to the change in the cross-sectional area of the ink ejection path becomes ink droplets and is ejected from each nozzle.

The transport processing unit Pr2 drives the transport motor 34 via the motor drive unit Dr2, rotates the transport roller pair 30, and transports the recording medium in the sub-scanning direction.

The carriage drive processing unit Pr3 drives the carriage motor 22 by PWM control via the motor drive unit Dr3, runs the endless belt 21, and reciprocates the carriage 17 in the main scanning direction. Therefore, the carriage drive processing unit Pr3 reads the target position and target speed of the carriage 17 from the ROM 81, receives the sensor output of the encoder 35, A / D converts the sensor output, and detects the position of the carriage 17. A PWM control signal as a control value is generated and sent to the carriage motor 22. The carriage motor 22 receives the PWM control signal, changes the rotation speed in proportion to the duty of the PWM control signal, accelerates or decelerates the carriage 17, and moves it to the target position at the target speed. Then, the carriage drive processing unit Pr3 sends the position of the carriage 17 to the recording processing unit Pr1, and the recording processing unit Pr1 calculates from each nozzle of the recording head Hdi according to the position of the carriage 17 based on the image data. Ink is ejected at the specified timing.

The reserve liquid supply processing unit Pr4 switches the switching valve v11 via the valve control unit Dr4, switches the waste liquid valve v13 via the valve control unit Dr6, and operates or stops the liquid feed pump 45 via the pump drive unit Dr7. Then, the preliminary liquid in the preliminary liquid tank Mti (FIG. 1) is filled in the first and second filling flow paths Ch1 and Ch2.

The air introduction processing unit Pr5 switches the air introduction valve v12 via the valve control unit Dr5 and introduces air into the first and second air introduction passages Ar1 and Ar2 to introduce the first and second air introduction passages Ar1 and Ar2. Preliminary liquid is discharged from the filling flow paths Ch1 and Ch2.

The ink supply processing unit Pr6 switches the switching valve v11 via the valve control unit Dr4, switches the waste liquid valve v13 via the valve control unit Dr6, and operates or stops the liquid feed pump 45 via the pump drive unit Dr7. The vacuum pump 48 is operated or stopped via the pump drive unit Dr8, and the ink in the ink tank Iti is filled into the first and second filling flow paths Ch1 and Ch2 after the preliminary liquid is discharged.

Next, the operation of the control unit 80 when printing is performed on the inkjet printer 10 will be described.

First, when the operator operates the operation unit of the operation panel 55 to start printing, the control unit 80 sets the switching valve v11, the air introduction valve v12, and the waste liquid valve v13 via the valve control units Dr4 to Dr6. The inkjet printer 10 (FIG. 2) is placed in the initial state at the switching position of 1, and the liquid feed pump 45 and the vacuum pump 48 are operated via the pump drive units Dr7 and Dr8.

The ink in the ink tank Iti is sent to the ink flow path Rmi, and is supplied to the recording head Hdi by the liquid feed pump 45 via the degassing module 47 of the ink flow path Rmi.

At this time, the vacuum pump 48 depressurizes the inside of the hollow fiber membrane of the degassing module 47 to create a vacuum, and degass the ink flowing in the degassing module 47.

Subsequently, the transfer processing unit Pr2 drives the transfer motor 34 via the motor drive unit Dr2, rotates the transfer roller pair 30, and conveys the recording medium in the sub-scanning direction, and the carriage drive processing unit Pr3 drives the motor. The carriage motor 22 is driven via the unit Dr3, the endless belt 21 is driven, the carriage 17 is moved in the main scanning direction, and the recording processing unit Pr1 drives the recording head Hdi via the head drive unit Dr1 to obtain ink. Is discharged.

By the way, at the time when the use of the inkjet printer 10 is started, the ink flow path Rmi and the recording head Hdi are not filled with ink and are filled with air or a storage liquid.

In this state, when the ink of the ink tank Iti is supplied to the recording head Hdi, the recording head Hdi is driven, and the ink is ejected in order to perform printing, the air remaining in the ink flow path Rmi and the recording head Hdi. , Preservative liquid, etc. are mixed in the ink, causing poor ink ejection.

Therefore, in the present embodiment, the preliminary liquid is filled in the first filling flow path Ch1 and the preliminary liquid is discharged from the ink flow path Rmi and the recording head Hdi before the use of the inkjet printer 10 is started. Subsequently, the first filling flow path Ch1 is filled with ink.

Next, the operation of the control unit 80 when the use of the inkjet printer 10 is started will be described.

FIG. 4 is a first flowchart showing the operation of the control unit according to the first embodiment of the present invention, and FIG. 5 is a second flowchart showing the operation of the control unit according to the first embodiment of the present invention.

In this case, in the initial state of the inkjet printer 10 (FIG. 2), the switching valve v11 (FIG. 1), the air introduction valve v12, and the waste liquid valve v13 are placed in the first switching position.

When the power of the inkjet printer 10 is turned on, first, the preliminary liquid supply processing unit Pr4 (FIG. 3) places the switching valve v11 in the second switching position, and the supply flow path K2 and the ink flow path Rmi are downstream. Communicate with the part of.

Next, the reserve liquid supply processing unit Pr4 operates the liquid feed pump 45 to supply the reserve liquid of the reserve liquid tank Mti to the ink flow path Rmi via the switching valve v11, and fills the first filling flow path Ch1. To do.

Here, when the volume of the first filling flow path Ch1 is set to the filling volume W1, the reserve liquid supply processing unit Pr4 fills the supply flow path K2 from the reserve liquid tank Mti to the switching valve v11 with the reserve liquid. In this state, the liquid feed pump 45 is operated until the amount of the reserve liquid fed by the liquid feed pump 45, that is, the reserve liquid feed amount A becomes the filling volume W1 or more. In this case, the reserve liquid feed amount A is 1.0 times to 1.0 times the filling volume W1, preferably 1 so that the first filling flow path Ch1 can be sufficiently filled with the reserve liquid. It is multiplied by 1 to 5.0 times. The unit liquid feed amount per rotation speed when the liquid feed pump 45 is operated is δa, and the total rotation speed of the liquid feed pump 45 required to fill the first filling flow path Ch1 with the reserve liquid. When is Na, the preliminary liquid feed amount A is
A = Na · δa
become.

When the reserve liquid feed amount A becomes the filling volume W1 or more, the reserve liquid supply processing unit Pr4 stops the feed liquid pump 45 and finishes the filling of the reserve liquid.

In the present embodiment, since the liquid feed pump 45 is operated until the reserve liquid feed amount A becomes the filling volume W1 or more, the reserve liquid can be sufficiently filled in the first filling flow path Ch1.

Subsequently, the air introduction processing unit Pr5 introduces air when a predetermined first time τ1 after the liquid feed pump 45 is stopped, and in the present embodiment, 1 [minute] to 10 [minute] elapses. The valve v12 is placed at the second switching position, and the branch flow path R1 and the downstream portion of the ink flow path Rmi are communicated with each other.

Next, the air introduction processing unit Pr5 operates the liquid feed pump 45 to introduce air from the air introduction valve v12 into the first air introduction flow path Ar1 via the branch flow path R1, and the first filling flow. The reserve liquid is discharged from the road Ch1.

In this case, since the reserve liquid is held in the first filling flow path Ch1 until the predetermined first time τ1 elapses, the reserve liquid is the corner portion, the wall, etc. in the first filling flow path Ch1. Is sufficiently wet, and even after being discharged from the first air introduction flow path Ar1, it remains in the corner portion or adheres to the wall in the first air introduction flow path Ar1.

Then, the air introduction processing unit Pr5 operates the liquid feed pump 45 until the discharge amount of the reserve liquid, that is, the reserve liquid discharge amount B becomes the filling volume W1 or more.

In this case, the reserve liquid discharge amount B is 1.0 to 1 to 1.0 times the filling volume W1 so that the reserve liquid in the first air introduction flow path Ar1 is sufficiently discharged, preferably 1. It is multiplied by 1 to 5.0 times.

When the unit air supply amount per rotation speed when the liquid feed pump 45 is operated is δb and the total rotation speed of the liquid feed pump 45 required to discharge the reserve liquid is Nb, the reserve The amount of liquid discharged B is
B = Nb ・ δb
become.

When the reserve liquid discharge amount B becomes the filling volume W1 or more, the air introduction processing unit Pr5 stops the liquid feed pump 45 and ends the discharge of the reserve liquid.

In the present embodiment, since the liquid feed pump 45 is operated until the reserve liquid discharge amount B becomes the filling volume W1 or more, air can be sufficiently introduced into the first air introduction flow path Ar1.

Subsequently, the ink supply processing unit Pr6 places the air introduction valve v12 at the first switching position, communicates the upstream side portion and the downstream side portion of the ink flow path Rmi, and switches the switching valve v11 to the first switching position. Placed at the position, the supply flow path K1 and the downstream portion of the ink flow path Rmi are communicated with each other to operate the vacuum pump 48. As a result, decompression in the hollow fiber membrane of the degassing module 47 is started.

Then, when a predetermined second time τ2 elapses after the vacuum pump 48 is operated, the inside of the hollow fiber membrane of the degassing module 47 is sufficiently depressurized, and a sufficient degree of vacuum is achieved, the ink supply process is performed. The unit Pr6 operates the liquid feeding pump 45 to supply the ink of the ink tank Iti to the ink flow path Rmi, and fills the first filling flow path Ch1 with the ink.

By the way, when filling the first filling flow path Ch1 with ink, it is necessary to discharge the preliminary liquid remaining in the first air introduction flow path Ar1 to the outside, unlike the case where the preliminary liquid is filled. A large number of hollow fiber membranes are arranged in the first air introduction flow path Ar1, in particular, in the degassing module 47, and the structure is complicated, and a large amount of reserve liquid remains. It is necessary to drain the liquid to the outside.

Therefore, in the ink supply processing unit Pr6, the amount of ink sent by the liquid feed pump 45, that is, the amount of ink sent C becomes equal to or larger than the increased filling volume W1 + α, which is the volume obtained by adding the addition value α to the filling volume W1. The liquid feed pump 45 is operated until. In the present embodiment, the added value α is equal to the volume of the flow path in the degassing module 47.

In this case, the first filling flow path Ch1 is filled with the preliminary liquid before the first filling flow path Ch1 is filled with ink, and the corners, walls, etc. in the first filling flow path Ch1 are wet. Therefore, the ink can be smoothly filled to every corner of the first filling flow path Ch1. Therefore, the ink feed amount C is 1.0 to 7.0 times, preferably 1.05 to 2.0 times, the increased filling volume W1 + α, and is smaller than the reserve liquid feed amount A. Will be done.

The unit liquid feed amount per rotation speed when the liquid feed pump 45 is operated is δ, and the total rotation speed of the liquid feed pump 45 required to fill the first filling flow path Ch1 with ink is set. When Nc is set, the ink feed amount C is
C = Nc ・ δ
become.

Then, when the ink feeding amount C becomes the increased filling volume W1 + α or more, the ink supply processing unit Pr6 stops the liquid feeding pump 45 and the vacuum pump 48, and finishes the ink filling.

In this way, the first filling flow path Ch1 can be filled with ink.

Next, the flowchart will be described.
Step S1 The reserve liquid supply processing unit Pr4 places the switching valve v11 in the second switching position.
Step S2 The reserve liquid supply processing unit Pr4 operates the liquid feed pump 45 to fill the reserve liquid into the first filling flow path Ch1.
Step S3 The reserve liquid supply processing unit Pr4 waits for the reserve liquid feed amount A to reach the first filling volume W1 or more. If the preliminary liquid feed amount A becomes the filling volume W1 or more, the process proceeds to step S4, and if the preliminary liquid feed amount A does not reach the filling volume W1 or more, the process returns to step S2.
Step S4 The reserve liquid supply processing unit Pr4 stops the liquid feed pump 45.
Step S5 The air introduction processing unit Pr5 places the air introduction valve v12 in the second switching position.
Step S6 The air introduction processing unit Pr5 operates the liquid feed pump 45 to discharge the reserve liquid.
Step S7 The air introduction processing unit Pr5 waits for the reserve liquid discharge amount B to reach the first filling volume W1 or more. If the reserve liquid discharge amount B becomes the filling volume W1 or more, the process proceeds to step S8, and if the reserve liquid discharge amount B does not reach the filling volume W1 or more, the process returns to step S6.
Step S8 The air introduction processing unit Pr5 stops the liquid feed pump 45.
Step S9 The ink supply processing unit Pr6 places the air introduction valve v12 in the first switching position.
Step S10 The ink supply processing unit Pr6 places the switching valve v11 in the first switching position.
Step S11 The ink supply processing unit Pr6 operates the vacuum pump 48.
Step S12 The ink supply processing unit Pr6 operates the liquid feed pump 45 to fill the first filling flow path Ch1 with ink.
Step S13 The ink supply processing unit Pr6 waits for the ink feed amount C to reach the increased filling volume W1 + α or more. If the ink feed amount C becomes the increased filling volume W1 + α or more, the process proceeds to step S14, and if the ink feed amount C does not exceed the increased filling volume W1 + α, the process returns to step S12.
Step S14 The ink supply processing unit Pr6 stops the liquid feed pump 45 and the vacuum pump 48, and ends the processing.

As described above, in the present embodiment, since the ink is filled after the preliminary liquid is discharged from the first filling flow path Ch1, the preliminary liquid is prevented from being mixed into the ink when the ink is filled. can do.

Therefore, since ink ejection failure does not occur, the image quality can be improved. Further, since it is not necessary to replace the preliminary liquid with ink, the amount of ink used until the ink can be ejected from the recording head Hdi can be reduced.

Further, when the preliminary liquid is discharged from the first filling flow path Ch1, the wall inside the first filling flow path Ch1 becomes wet, so that the ink can be smoothly applied to every corner of the first filling flow path Ch1. Can be filled in.

Therefore, the amount of ink used until the ink can be ejected from the recording head Hdi can be further reduced.

For example, in the present embodiment, the first filling flow path Ch1 is filled with the preliminary liquid of the preliminary liquid feeding amount A, the preliminary liquid is discharged, and then ink is fed to the first filling flow path Ch1. Although the ink of the liquid amount C is filled, after the preliminary liquid of the preliminary liquid feeding amount A is supplied to the first filling flow path Ch1, the first filling flow without discharging the preliminary liquid is discharged. When ink is supplied to the path Ch1 and the preliminary liquid is replaced with ink, the ink feed amount C', which is the amount of ink used until the ink can be ejected from the recording head Hdi, is
C'= 1.5 x C
become.

By the way, when the degassing module 47 is used for a long period of time, the hollow fiber membrane is deteriorated and deteriorated, a foreign matter adhering layer is formed on the surface of the hollow fiber membrane, and the hollow fiber membrane is clogged. , The degassing performance of the degassing module 47 deteriorates. Therefore, it is necessary to replace the degassing module 47 at regular intervals.

Next, a second embodiment of the present invention in which the degassing module 47 is replaced will be described. The same reference numerals are given to those having the same structure as that of the first embodiment, and the effects of the same embodiment are used for the effects of the invention due to having the same structure.

FIG. 6 is a first flowchart showing the operation of the control unit according to the second embodiment of the present invention, and FIG. 7 is a second flowchart showing the operation of the control unit according to the second embodiment of the present invention, FIG. Is a third flowchart showing the operation of the control unit according to the second embodiment of the present invention.

In this case, in the initial state of the inkjet printer 10 (FIG. 2) as the printing device, the switching valve v11 (FIG. 1), the air introduction valve v12, and the waste liquid valve v13 are placed at the first switching positions.

First, the reserve liquid supply processing unit Pr4 (FIG. 3) places the switching valve v11 at the second switching position, communicates the supply flow path K2 with the downstream portion of the ink flow path Rmi, and sets the waste liquid supply valve v13 to the second. It is placed at the switching position of 2, and the portion on the upstream side of the ink flow path Rmi and the branch flow path R2 are communicated with each other.

Next, the reserve liquid supply processing unit Pr4 operates the liquid feed pump 45 to fill the reserve liquid of the reserve liquid tank Mti as the reserve liquid storage unit into the second filling flow path Ch2 as a predetermined filling flow path. ..

Here, when the volume of the second filling flow path Ch2 is set to the waste liquid volume W2, the reserve liquid supply processing unit Pr4 fills the supply flow path K2 from the reserve liquid tank Mti to the switching valve v11 with the reserve liquid. In this state, the liquid feeding pump 45 is operated until the preliminary liquid feeding amount D becomes the waste liquid volume W2 or more. The unit liquid feed amount per rotation speed when the liquid feed pump 45 is operated is δa, and the feed required to fill the first filling flow path Ch1 as a predetermined filling flow path with the reserve liquid. When the total rotation speed of the liquid pump 45 is Nd, the preliminary liquid feed amount D is
D = Nd · δa
become.

When the reserve liquid feed amount D becomes the waste liquid volume W2 or more, the reserve liquid supply processing unit Pr4 stops the feed liquid pump 45 and finishes the filling of the reserve liquid.

Subsequently, the air introduction processing unit Pr5 places the air introduction valve v12 at the second switching position, and communicates the branch flow path R1 with the portion on the downstream side of the ink flow path Rmi.

Next, the air introduction processing unit Pr5 operates the liquid feed pump 45 to introduce air from the air introduction valve v12 through the branch flow path R1 into the second air introduction flow path Ar2, and the reserve liquid is discharged into the waste liquid valve v13. The waste liquid is discharged from the second filling flow path Ch2 to the waste liquid bottle 49 as the waste liquid storage portion.

The air introduction processing unit Pr5 operates the liquid feed pump 45 until the reserve liquid discharge amount E by the liquid feed pump 45 reaches the waste liquid volume W2 or more.

When the unit air supply amount per rotation speed when the liquid supply pump 45 is operated is δb and the total rotation speed of the liquid supply pump 45 required for discharging the reserve liquid is Ne, the reserve The amount of liquid discharged E is
E = Ne · δb
become.

Next, the air introduction processing unit Pr5 stops the liquid feed pump 45 and ends the introduction of air.

Then, the operator replaces the degassing module 47 as the degassing device with a new degassing module 47. At this time, since air is introduced into the second air introduction flow path Ar2 and the reserve liquid is discharged, the reserve liquid does not leak from the degassing module 47 when the degassing module 47 is replaced.

Subsequently, the reserve liquid supply processing unit Pr4 places the air introduction valve v12 at the first switching position, and communicates the upstream side portion and the downstream side portion of the ink flow path Rmi.

Next, the reserve liquid supply processing unit Pr4 operates the liquid feed pump 45 until the reserve liquid feed amount D becomes the waste liquid volume W2 or more, and fills the reserve liquid into the second filling flow path Ch2. When the reserve liquid feed amount D becomes the waste liquid volume W2 or more, the reserve liquid supply processing unit Pr4 stops the feed liquid pump 45 and finishes filling the reserve liquid.

Then, the air introduction processing unit Pr5 places the air introduction valve v12 at the second switching position, communicates the flow path between the branch flow path R1 and the waste liquid bottle 49, operates the liquid feed pump 45, and branches the flow. Air is introduced through the passage R1, air is introduced into the second air introduction flow path Ar2, and the reserve liquid is discharged to the waste liquid bottle 49 via the waste liquid valve v13.

Subsequently, the air introduction processing unit Pr5 operates the liquid feed pump 45 until the reserve liquid discharge amount E by the liquid feed pump 45 reaches the waste liquid volume W2 or more.

Then, when the reserve liquid discharge amount E becomes the waste liquid volume W2 or more, the air introduction processing unit Pr5 stops the liquid feed pump 45 and ends the introduction of air into the second air introduction flow path Ar2.

Subsequently, the ink supply processing unit Pr6 places the air introduction valve v12 at the first switching position, communicates the upstream side portion and the downstream side portion of the ink flow path Rmi, and switches the switching valve v11 to the first switching position. Placed at the position, the supply flow path K1 and the downstream portion of the ink flow path Rmi are communicated with each other to operate the vacuum pump 48. As a result, decompression in the hollow fiber membrane of the degassing module 47 is started.

Then, when a predetermined second time τ2 elapses after the vacuum pump 48 is operated, the inside of the hollow fiber membrane of the degassing module 47 is sufficiently depressurized, and a sufficient degree of vacuum is achieved, ink is supplied. The processing unit Pr6 operates the liquid feed pump 45 to fill the second filling flow path Ch2 with the ink of the ink tank Iti, and wastes the preliminary liquid remaining in the second air introduction flow path Ar2 together with the ink. It is discharged to the waste liquid bottle 49 via the valve v13.

Subsequently, the ink supply processing unit Pr6 operates the liquid feed pump 45 until the ink feed amount F by the liquid feed pump 45 reaches the increased waste liquid volume W2 + α or more.

When the ink feeding amount F becomes the increased waste liquid volume W2 + α or more, the ink supply processing unit Pr6 stops the liquid feeding pump 45 and the vacuum pump 48, and finishes the ink filling.

Then, the ink supply processing unit Pr6 places the waste liquid valve v13 in the first switching position, communicates the upstream side portion and the downstream side portion of the ink flow path Rmi, and degass is performed by the degassing module 47. The ink after the ink is supplied to the recording head Hdi.

As described above, in the present embodiment, after the air is introduced into the second air introduction flow path Ar2 and the preliminary liquid is discharged, the second filling flow path Ch2 is removed before the ink is filled. Since the air module 47 is replaced, the degassing module 47 can be smoothly replaced without the preliminary liquid or ink leaking from the degassing module 47 when the degassing module 47 is replaced.

Next, the flowchart will be described.
Step S21 The reserve liquid supply processing unit Pr4 places the switching valve v11 and the waste liquid valve v13 in the second switching position.
Step S22 The reserve liquid supply processing unit Pr4 operates the liquid feed pump 45 to fill the reserve liquid into the second filling flow path Ch2.
Step S23 The reserve liquid supply processing unit Pr4 waits for the reserve liquid feed amount D to reach the waste liquid volume W2 or more. If the reserve liquid feed amount D becomes the waste liquid volume W2 or more, the process proceeds to step S24, and if the reserve liquid feed amount D does not reach the waste liquid volume W2 or more, the process returns to step S22.
Step S24 The reserve liquid supply processing unit Pr4 stops the liquid feed pump 45.
Step S25 The air introduction processing unit Pr5 sets the air introduction valve v12 at the second switching position.
Step S26 The air introduction processing unit Pr5 operates the liquid feed pump 45 to discharge the reserve liquid to the waste liquid bottle 49.
Step S27 The air introduction processing unit Pr5 waits for the reserve liquid discharge amount E to reach the waste liquid volume W2 or more. If the reserve liquid discharge amount E becomes the waste liquid volume W2 or more, the process proceeds to step S28, and if the reserve liquid discharge amount E does not reach the waste liquid volume W2 or more, the process returns to step S26.
Step S28 The air introduction processing unit Pr5 stops the liquid feed pump 45 and ends the introduction of air.
Step S29 The operator replaces the degassing module 47 with a new degassing module 47.
Step S30 The reserve liquid supply processing unit Pr4 places the air introduction valve v12 in the first switching position.
Step S31 The reserve liquid supply processing unit Pr4 operates the liquid feed pump 45 to fill the reserve liquid into the second filling flow path Ch2.
Step S32 The reserve liquid supply processing unit Pr4 waits for the reserve liquid feed amount D to reach the waste liquid volume W2 or more. If the reserve liquid feed amount D becomes the waste liquid volume W2 or more, the process proceeds to step S33, and if the reserve liquid feed amount D does not reach the waste liquid volume W2 or more, the process returns to step S31.
Step S33 The reserve liquid supply processing unit Pr4 stops the liquid feed pump 45.
Step S34 The air introduction processing unit Pr5 sets the air introduction valve v12 at the second switching position.
Step S35 The air introduction processing unit Pr5 operates the liquid feed pump 45 to discharge the reserve liquid to the waste liquid bottle 49.
Step S36 The air introduction processing unit Pr5 waits for the reserve liquid discharge amount E to reach the waste liquid volume W2 or more. If the reserve liquid discharge amount E becomes the waste liquid volume W2 or more, the process proceeds to step S37, and if the reserve liquid discharge amount E does not reach the waste liquid volume W2 or more, the process returns to step S35.
Step S37 The air introduction processing unit Pr5 stops the liquid feed pump 45 and ends the introduction of air.
Step S38 The ink supply processing unit Pr6 places the air introduction valve v12 in the first switching position.
Step S39 The ink supply processing unit Pr6 places the switching valve v11 in the first switching position.
Step S40 The ink supply processing unit Pr6 operates the vacuum pump 48.
Step S41 The ink supply processing unit Pr6 operates the liquid feed pump 45 to fill the second filling flow path Ch2 with ink.
Step S42 The ink supply processing unit Pr6 waits for the ink feed amount F to reach the increased waste liquid volume W2 + α or more. If the ink feed amount F does not exceed the increased waste liquid volume W2 + α, the process proceeds to step S43, and if the ink feed amount F does not exceed the increased waste liquid volume W2 + α, the process returns to step S41.
Step S43 The ink supply processing unit Pr6 stops the liquid feed pump 45 and the vacuum pump 48.
Step S44 The ink supply processing unit Pr6 places the waste liquid valve v13 in the first switching position, and ends the processing.

Although the inkjet printer 10 is described in each of the above-described embodiments, the present invention can be applied to printing devices such as copiers, facsimiles, and multifunction devices.

The present invention is not limited to each of the above-described embodiments, and various modifications can be made based on the gist of the present invention, and these are not excluded from the scope of the present invention.

10 Inkjet printers Ch1, Ch2 1st and 2nd filling flow paths Hdi Recording head Iti Ink tank Mti Preliminary liquid tank Pr4 Preliminary liquid supply processing unit Pr5 Air introduction processing unit Pr6 Ink supply processing unit Rmi Ink flow path v11 Switching valve v12 Air Ink valve

Claims (12)

(A) Recording head and
(B) An ink accommodating portion for accommodating ink and
(C) A reserve liquid accommodating portion for accommodating the reserve liquid and
(D) An ink flow path arranged between the ink accommodating portion and the recording head,
(E) A preliminary liquid supply processing unit that supplies a preliminary liquid to an injection port formed in the ink flow path and fills a predetermined filling flow path with the preliminary liquid.
(F) An air introduction processing unit that introduces air from an introduction port formed in the ink flow path and discharges a preliminary liquid from the filling flow path.
(G) A printing apparatus comprising an ink supply processing unit for filling the filling flow path with ink after the preliminary liquid is discharged. (A) An degassing device for degassing ink is provided in the ink flow path.
(B) The printing apparatus according to claim 1, wherein the injection port is formed between an ink accommodating portion and an deaeration device in an ink flow path. The printing device according to claim 2, wherein the introduction port is formed between the injection port and the degassing device in the ink flow path. The printing apparatus according to any one of claims 1 to 3, wherein the filling flow path is formed by a flow path including the ink flow path and a recording head. (A) A waste liquid port connected to the waste liquid storage portion is formed in the ink flow path.
(B) The printing apparatus according to any one of claims 1 to 4, wherein the reserve liquid is discharged from the filling flow path to the waste liquid storage unit via the waste liquid port. The printing apparatus according to claim 5, wherein the filling flow path is formed by a portion of the ink flow path on the upstream side of the waste liquid port. In an ink filling method of a printing apparatus having a recording head, an ink accommodating portion for accommodating ink, a preparatory liquid accommodating portion for accommodating a preliminary liquid, and an ink flow path arranged between the ink accommodating portion and the recording head.
(A) A preliminary liquid is supplied to an injection port formed in the ink flow path, and a predetermined filling flow path is filled with the preliminary liquid.
(B) Air is introduced from the introduction port formed in the ink flow path, and the preliminary liquid is discharged from the filling flow path.
(C) An ink filling method characterized by filling the filling flow path with ink after the preliminary liquid is discharged. The ink filling method according to claim 7, wherein the wall in the filling flow path becomes wet by filling the filling flow path with the preliminary liquid and discharging the preliminary liquid from the filling flow path. (A) An degassing device for degassing ink is provided in the ink flow path.
(B) The ink filling method according to claim 7 or 8, wherein the ink filled in the filling flow path is supplied to the recording head after being degassed by the degassing device. A claim in which air is introduced from an introduction port formed in the ink flow path, preliminary liquid is discharged from the filling flow path, and then the deaerator is replaced before the filling flow path is filled with ink. 9. The ink filling method according to 9. After replacing the degassing device, a preliminary liquid is supplied to the injection port formed in the ink flow path, the filling flow path is filled with the preliminary liquid, air is introduced from the introduction port, and the preliminary liquid is introduced from the filling flow path. The ink filling method according to claim 10, wherein the ink is filled in the filling flow path after the reserve liquid is discharged. (A) A waste liquid port connected to the waste liquid storage portion is formed in the ink flow path.
(B) The ink filling method according to any one of claims 7 to 11, wherein the reserve liquid is discharged from the filling flow path to the waste liquid storage unit via the waste liquid port.

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