JP2020131668A - Image formation system - Google Patents

Abstract

To realize execution of preliminary discharge according to individual discharge parts.SOLUTION: An image formation system includes: discharge means having a plurality of discharge parts provided with at least a first discharge part for discharging ink to a first surface of a recording material and a second discharge part and forming an image on the recording material; and control means for controlling execution of preliminary discharge that the discharge parts discharge ink before printing, for individual discharge parts including the first discharge part and the second discharge part.SELECTED DRAWING: Figure 4

Description

The present invention relates to an image forming system.

Patent Document 1 describes that after performing a discharge inspection of a discharge head in a discharge inspection cleaning mode, a cleaning process is performed when a discharge defect is determined by the discharge inspection.

Japanese Unexamined Patent Publication No. 2012-224013

In an image forming system having an ejection unit for ejecting ink, the ejection unit may perform preliminary ejection for ejecting ink before printing.
Here, for example, when a plurality of discharge portions are provided in the image forming system, the execution of the preliminary discharge may be controlled collectively for the plurality of discharge portions. In this case, the execution of the preliminary discharge is controlled according to the individual discharge portions. The preliminary discharge could not be performed.
An object of the present invention is to realize the execution of preliminary discharge according to each discharge unit.

The invention according to claim 1 has a plurality of ejection portions provided with at least a first ejection portion and a second ejection portion for ejecting ink on the first surface of the recording material, and forms an image on the recording material. Each of the first ejection unit and the second ejection unit is provided with a control means for controlling the execution of preliminary ejection in which the ejection unit ejects ink before printing. , An image forming system.
The invention according to claim 2 is the image forming system according to claim 1, wherein the control means controls the execution of the preliminary ejection from the printing instruction prior to printing.
In the invention according to claim 3, the first ejection unit ejects black ink, the second ejection unit ejects a color ink different from the black ink, and the control means is the recording material. When the instruction to perform black-and-white printing on the first surface is included in the instruction, the first ejection unit is made to execute the preliminary ejection a predetermined number of times, and the second ejection portion is subjected to the preliminary ejection. The image forming system according to claim 2, wherein the image forming system is executed or not executed a number of times less than a predetermined number of times.
According to the fourth aspect of the present invention, the plurality of ejection units include a third ejection unit that ejects the black ink onto the second surface of the recording material, and color printing on the second surface without being used for black-and-white printing. When the instruction includes an instruction to perform color printing on the second surface of the recording material, the control means includes the fourth ejection unit for ejecting the color ink of the color used in the above. 3. The image forming system according to claim 3, wherein the discharge unit and the fourth discharge unit execute the preliminary discharge a predetermined number of times.
In the invention according to claim 5, the first ejection unit ejects the first color ink, the second ejection unit ejects the second color ink, and the control means is the first of the recording materials. When the instruction includes an instruction to perform color printing using the first color ink and not the second color ink on one surface, the first ejection unit is made to execute the preliminary ejection a predetermined number of times. The image forming system according to claim 2, wherein the second ejection unit is made to execute the preliminary ejection a number of times less than a predetermined number of times, or is not executed.
According to the sixth aspect of the present invention, the discharge means can move the first discharge part and the second discharge part, and the control means has the first discharge part and the second discharge part. The image forming system according to claim 1, wherein the execution of the preliminary discharge is controlled based on the positions of the individual discharge portions.
The invention according to claim 7 is the case where the control means has the first discharge unit located at a predetermined position and the second discharge unit is located at a position different from the predetermined position. The image forming system according to claim 6, wherein the first discharge unit does not execute the preliminary discharge, and the second discharge unit executes the preliminary discharge.
In the invention according to claim 8, when the ink is ejected from the individual ejection portions of the first ejection portion and the second ejection portion, the ink adheres to the recording material at the predetermined position. The image forming system according to claim 7, wherein the position is the position of the discharge portion.
The invention according to claim 9 is characterized in that the control means controls the execution of the preliminary discharge based on the state of each discharge unit of the first discharge unit and the second discharge unit. Item 2. The image forming system according to item 1.
The invention according to claim 10 is that the discharge means moves the first discharge unit and the second discharge unit to a storage position for storing the plurality of discharge units when the printing instruction is not received. The control means can reach a predetermined time when the first discharge unit is not located at the storage position, and the second discharge unit is not located at the storage position. If has not reached the predetermined time, the first discharge unit is made to execute the preliminary discharge a predetermined number of times, and the second discharge unit is made to perform the preliminary discharge more than the predetermined number of times. The image forming system according to claim 9, wherein the image forming system is executed or not executed a small number of times.
The invention according to claim 11, wherein the control means is based on the amount of ink ejected from the individual ejection portions of the first ejection portion and the second ejection portion by forming an image relating to the latest printing. The image forming system according to claim 9, wherein the execution of the preliminary discharge is controlled.
In the invention according to claim 12, the control means does not reach a predetermined amount of ink ejected from the first ejection unit in the latest printing, and ejects the ink from the second ejection unit. When the amount of ink reached the predetermined amount, the first ejection unit is made to execute the preliminary ejection a predetermined number of times, and the second ejection portion is subjected to the preliminary ejection. The image forming system according to claim 11, wherein the image forming system is executed or not executed a number of times less than the number of times.
The invention according to claim 13 is characterized in that the control means controls the number of executions of the preliminary discharge for each individual discharge unit of the first discharge unit and the second discharge unit. The image forming system described.

According to the invention of claim 1, it is possible to realize the execution of preliminary discharge according to each discharge portion.
According to the second aspect of the present invention, the control means can control the execution of the preliminary ejection according to the content of the printing instruction.
According to the invention of claim 3, the second ejection that is not used for printing is not used as compared with the case where the first ejection unit and the second ejection unit execute the preliminary ejection a predetermined number of times regardless of the content of the printing instruction. It is possible to reduce the amount of ink ejected from the portion by preliminary ejection.
According to the invention of claim 4, even if the color of the ink used for printing is different between the first surface and the second surface of the recording material, the control means can be used according to the color of the ink used for printing. The execution of pre-discharge can be controlled.
According to the invention of claim 5, in the case where color printing is performed, the preliminary ejection is performed from the second ejection portion which is not used for color printing, as compared with the case where all the ejection portions are subjected to the preliminary ejection a predetermined number of times. The amount of ejected ink can be reduced.
According to the sixth aspect of the present invention, the control means can control the execution of the preliminary discharge according to the position of each discharge unit.
According to the invention of claim 7, the position where the preliminary discharge is not executed can be set in the first discharge part and the second discharge part.
According to the eighth aspect of the present invention, the first discharge unit and the second discharge unit perform preliminary discharge regardless of the position of the first discharge unit and the position of the second discharge unit, as compared with the case where the first discharge unit and the second discharge unit execute the preliminary discharge. When the second ejection unit executes the preliminary ejection, it is possible to prevent the ejected ink from adhering to the recording material.
According to the invention of claim 9, the control means can control the execution of the preliminary discharge according to the state of each discharge unit.
According to the invention of claim 10, as compared with the case where the first discharge part and the second discharge part execute the preliminary discharge a predetermined number of times regardless of the position of the first discharge part and the position of the second discharge part. It is possible to reduce the amount of ink ejected by the preliminary ejection from the second ejection unit where the time not located at the storage position has not reached a predetermined time.
According to the invention of claim 11, it is possible to make the control means control the execution of the preliminary ejection according to the amount of ink ejected from each ejection unit by forming an image relating to the latest printing.
According to the invention of claim 12, preliminary ejection is predetermined for the first ejection portion and the second ejection portion regardless of the amount of ink ejected from the first ejection portion and the amount of ink ejected from the second ejection portion. It is possible to reduce the amount of ink ejected by the preliminary ejection from the second ejection portion where a predetermined amount of ink has not been ejected in the latest printing, as compared with the case where the ink is executed a specified number of times.
According to the thirteenth aspect of the present invention, the control means can control the number of times the preliminary discharge is executed according to the necessity of the preliminary discharge in the individual discharge portions of the first discharge portion and the second discharge portion.

It is a figure which shows the whole structure example of the image formation system by this embodiment. It is a figure which shows the structure of the image forming apparatus. It is a block diagram which showed the functional configuration example of a server device. It is a flowchart which showed the flow of the preliminary discharge control processing. It is a flowchart which showed the flow of the preliminary discharge control processing in modification 1. It is a flowchart which showed the flow of the preliminary discharge control processing in the modification 2. It is a flowchart which showed the flow of the preliminary discharge control processing in the modification 3.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
<Configuration of image formation system>
FIG. 1 is a diagram showing an overall configuration example of the image forming system 1 according to the present embodiment. The image forming system 1 of the present embodiment includes a server device 10, an image forming device 20, and a terminal device 30. The server device 10, the image forming device 20, and the terminal device 30 are connected via a network.

The server device 10 is a server that transmits / receives data between the image forming device 20 and the terminal device 30 via a network. The server device 10 is realized by, for example, a computer. The server device 10 may be configured by a single computer, or may be realized by distributed processing by a plurality of computers.

The image forming apparatus 20 of the present embodiment is an inkjet printer that forms an image by ejecting ink onto continuous paper P in which each page is continuously formed in the paper conveying direction. Examples of the continuous paper P include roll paper, continuous forms, and the like. Further, the continuous paper P is an example of a recording material.

The terminal device 30 is a computer device that is operated when the user gives a print instruction. The terminal device 30 gives an instruction such as printing to the server device 10 via the network. The terminal device 30 is realized by, for example, a computer, a tablet-type information terminal, or other information processing device.

<Configuration of image forming apparatus>
FIG. 2 is a diagram showing the configuration of the image forming apparatus 20.
The image forming apparatus 20 includes a first image forming unit 201, a second image forming unit 204, a supply unit 207, a winding unit 208, a buffer device 209, and a control unit 210.

The first image forming unit 201 forms an image on the surface of the continuous paper P. The first image forming unit 201 is a yellow (Y) first inkjet head 203Y and magenta (M) corresponding to four color inks of yellow (Y), magenta (M), cyan (C), and black (K), respectively. ), A first inkjet head 203C of cyan (C), and a first inkjet head 203K of black (K). In addition, the first image forming unit 201 includes a first driving unit 202 that drives the first inkjet head. Here, the surface of the continuous paper P is regarded as the first surface of the recording material.
In the following description, when each first inkjet head is described without distinction, it is referred to as the first inkjet head 203. Further, when the first inkjet head 203Y of yellow (Y), the first inkjet head 203M of magenta (M), and the first inkjet head 203C of cyan (C) are collectively described, the first color inkjet head It is called 203.

The second image forming unit 204 forms an image on the back surface of the continuous paper P. The second image forming unit 204 is a yellow (Y) second inkjet head 206Y and magenta (M) corresponding to four color inks of yellow (Y), magenta (M), cyan (C), and black (K), respectively. ), A second inkjet head 206C of cyan (C), and a second inkjet head 206K of black (K). Further, the second image forming unit 204 includes a second driving unit 205 that drives the second inkjet head. Here, the back surface of the continuous paper P is regarded as the second surface of the recording material.

In the following description, when each second inkjet head is described without distinction, it is referred to as a second inkjet head 206. Further, when the yellow (Y) second inkjet head 206Y, the magenta (M) second inkjet head 206M, and the cyan (C) second inkjet head 206C are collectively described, the color second inkjet head 206C will be described together. It is called 206. When the first inkjet head 203 and the second inkjet head 206 are described without distinction, they are simply referred to as an inkjet head. Further, when the color first inkjet head 203 and the color second inkjet head 206 are described without distinction, they are simply referred to as a color inkjet head. Further, when the first drive unit 202 and the second drive unit 205 are described without distinction, they are simply referred to as drive units.

An inkjet head as an example of a ejection unit forms an image on continuous paper P by ejecting ink droplets by a known means such as a thermal method or a piezoelectric method. The inkjet head has a length corresponding to a width equal to or larger than a region where an image is formed with respect to the continuous paper P. Further, the inkjet head is provided with a nozzle for ejecting ink over the entire width of the region where an image is formed with respect to the continuous paper P.

The drive unit can move the inkjet head to at least a printing position, a storage position, and a maintenance position.
The printing position is the position of the inkjet head where the ink adheres to the continuous paper P when the ink is ejected from the inkjet head.
The storage position is a position where the inkjet head is stored when the image forming system 1 is not instructed to print. The inkjet head located in the storage position is covered with a cap containing water to prevent the nozzle of the inkjet head from drying out.
The maintenance position is the position of the inkjet head within the reach of the user. In the state where the inkjet head is located at the maintenance position, the user performs maintenance of the inkjet head and the like.
The first image forming unit 201 and the second image forming unit 204 are taken as ejection means for forming an image on the continuous paper P.

The supply unit 207 accommodates the continuous paper P. Further, the supply unit 207 supplies the continuous paper P to the downstream side in the paper transport direction.
The winding unit 208 winds up the continuous paper P on which the image is formed by the first image forming unit 201 and the second image forming unit 204.
The buffer device 209 has an inversion mechanism that inverts the front surface and the back surface of the continuous paper P.

When the control unit 210 receives a print instruction from the server device 10, the control unit 210 controls the operations of the first image forming unit 201 and the second image forming unit 204 based on the printing instruction. In addition, the control unit 210 manages the position of the inkjet head. Then, the position information regarding the position of the inkjet head is transmitted to the server device 10. This position information includes information indicating which of the printing position, the storage position, the maintenance position, and other positions the individual inkjet heads provided in the image forming apparatus 20 are located.

<Preliminary discharge>
Here, the preliminary ejection performed by the inkjet head will be described.
The nozzle of the inkjet head is in a state where ink remains after the ink is ejected. Therefore, when the ink is not ejected in a low temperature environment or for a long period of time, when the nozzle restarts the ink ejection operation, the ink ejection becomes unstable due to the residual ink or from the nozzle. Ink ejection failure may occur, such as ink not being ejected.

In order to suppress such ink ejection failure, the inkjet head may perform preliminary ejection. Preliminary ejection means that the nozzle of the inkjet head ejects ink before printing. Examples of the preliminary discharge include a dummy jet and a warm-up. The dummy jet means that the inkjet head ejects ink for a purpose other than forming an image on the continuous paper P before printing. Further, the warm-up means that the inkjet head ejects ink to the continuous paper P in preparation for printing.
The inkjet head pre-discharges and supplies fresh ink into the nozzle to eliminate the cause of poor ejection of ink that is not suitable for image formation due to thickening due to evaporation of air bubbles, dust, or solvent. Maintain a state suitable for image formation.

<Functional configuration of server device>
Next, the functional configuration of the server device 10 will be described. FIG. 3 is a block diagram showing a functional configuration example of the server device 10.
The server device 10 includes an instruction receiving unit 11, a head information acquisition unit 12, a calculation unit 13, a setting information acquisition unit 14, and a head control unit 15.

The instruction receiving unit 11 receives printing instructions. The instruction receiving unit 11 receives, for example, a printing instruction given by the operation of the terminal device 30 by the user. Further, at this time, the instruction receiving unit 11 acquires instruction information regarding the printing instruction from the terminal device 30. This instruction information includes information indicating the print setting of the print received by the instruction reception unit 11. The print settings include, for example, a setting of either single-sided printing or double-sided printing, a setting of either black-and-white printing or color printing, and a setting of which color image is formed at which position on the continuous paper P. And so on. The instruction receiving unit 11 transmits the acquired instruction information to the calculation unit 13 and the head control unit 15.

The head information acquisition unit 12 acquires the above-mentioned position information from the control unit 210 of the image forming apparatus 20, for example, every second. Then, this position information acquired from the control unit 210 is transmitted to the head control unit 15.

The calculation unit 13 calculates the amount of ink ejected from each of the inkjet heads provided in the image forming apparatus 20. Specifically, when the calculation unit 13 acquires the instruction information from the instruction reception unit 11, the individual inkjet heads are based on the print settings included in the instruction information and the image data to be printed related to the instruction information. The amount of ink ejected by printing is calculated for each. The calculation unit 13 transmits ink amount information indicating the amount of ink calculated for each individual inkjet head to the head control unit 15.

The setting information acquisition unit 14 acquires information related to print settings. The setting information acquisition unit 14 acquires, for example, information about print settings made by the user operating the terminal device 30. This print setting is a setting that is set separately from the print setting that is performed together with the print instruction. The setting information acquisition unit 14 transmits the acquired print setting information to the head control unit 15.
The head control unit 15 controls the execution of preliminary ejection by the inkjet head based on the information acquired from the instruction receiving unit 11, the head information acquisition unit 12, the calculation unit 13, and the setting information acquisition unit 14.

<Preliminary discharge control processing>
Next, the preliminary discharge control process will be described. Here, the preliminary ejection control process is a process in which the head control unit 15 controls the execution of preliminary ejection of the inkjet head. The preliminary ejection control process is realized by the head control unit 15 instructing the control unit 210 of the image forming apparatus 20 to execute the preliminary ejection by the inkjet head.
FIG. 4 is a flowchart showing the flow of the preliminary discharge control process.

First, the head control unit 15 determines whether or not a printing instruction has been given (S101). Specifically, the head control unit 15 determines whether or not a print instruction has been given depending on whether or not the instruction information has been acquired from the instruction reception unit 11. While the negative result continues, the head control unit 15 repeats the determination operation in step 101.

On the other hand, when the head control unit 15 acquires the instruction information, an affirmative result is obtained and the process proceeds to step 102.
The head control unit 15 refers to information regarding print settings included in the instruction information. Then, it is determined whether or not the instructed printing is color printing (S102).
When the instructed print is color printing (YES in S102), the head control unit 15 determines whether or not the instructed print is double-sided printing (S103).

When the instructed printing is double-sided printing (YES in S103), the head control unit 15 reserves all the first inkjet heads 203 and all the second inkjet heads 206 prior to the instructed printing. Discharge is executed (S104).
On the other hand, when the instructed print is not double-sided printing (NO in S103), the head control unit 15 determines that the instructed print is single-sided printing. In this case, the head control unit 15 causes all the first inkjet heads 203 to perform preliminary ejection prior to printing (S105). On the other hand, the head control unit 15 does not cause all the second inkjet heads 206 to perform preliminary ejection.

If a negative result is obtained in step 102, the head control unit 15 determines that the instructed print is black-and-white print. In this case, the head control unit 15 determines whether or not the instructed printing is double-sided printing (S106).
When the instructed printing is double-sided printing (YES in S106), the head control unit 15 reserves the black first inkjet head 203K and the black second inkjet head 206K prior to the instructed printing. Discharge is executed (S107). On the other hand, the head control unit 15 does not cause the color first inkjet head 203 and the color second inkjet head 206 to perform preliminary ejection.
If the instructed print is not double-sided printing (NO in S106), the head control unit 15 determines that the instructed print is single-sided printing. In this case, the head control unit 15 causes the black first inkjet head 203K to perform preliminary ejection prior to printing instructed (S108). On the other hand, the head control unit 15 does not cause the color first inkjet head 203 and all the second inkjet heads 206 to perform preliminary ejection.

As described above, in the present embodiment, the head control unit 15 controls the execution of the preliminary ejection for each individual inkjet head provided in the image forming apparatus 20.
In particular, in the present embodiment, the head control unit 15 controls the execution of preliminary ejection from the printing instruction prior to printing. More specifically, the inkjet head used for printing is made to perform preliminary ejection, while the inkjet head not used for printing is not allowed to perform preliminary ejection.

As described above, the preliminary discharge is performed to maintain a state suitable for image formation. Therefore, an inkjet head that is not used for printing requires less pre-discharge than an inkjet head that is used for printing. Therefore, in the present embodiment, whether or not the inkjet head is used for printing is set as an execution condition for preliminary ejection.

In the example shown in FIG. 4, the inkjet head not used for printing is not allowed to perform preliminary ejection, but the present invention is not limited to this. The head control unit 15 may cause the inkjet head not used for printing to perform preliminary ejection a smaller number of times than the inkjet head used for printing. This number of times is, for example, the number of times that the inkjet head ejects ink in the dummy jet. Further, this number of times may be the number of times when the number of times that the inkjet head forms an image on a predetermined number of continuous sheets P of the first page in warm-up is counted as one time. The number of pages on the first page is, for example, one.

For example, when the printing instruction includes an instruction to perform black-and-white printing on the surface of the continuous paper P, the head control unit 15 causes the black first inkjet head 203K to execute preliminary ejection a predetermined number of times, and yellow. The first inkjet head 203Y of the above may or may not execute the preliminary ejection a number of times less than a predetermined number of times. Further, when the printing instruction includes an instruction to perform color printing on the back surface of the continuous paper P, the head control unit 15 preliminarily discharges the black second inkjet head 206K and the yellow second inkjet head 206Y. It may be executed a predetermined number of times. Here, the black first inkjet head 203K is regarded as a first ejection unit that ejects black ink. Further, the yellow first inkjet head 203Y is regarded as a second ejection unit that ejects a color ink different from the black ink. Further, the black second inkjet head 206K is regarded as a third ejection unit that ejects black ink on the back surface of the continuous paper P. Further, the yellow second inkjet head 206Y is regarded as a fourth ejection unit that ejects color ink of a color that is not used for black-and-white printing but is used for color printing on the back surface of the continuous paper P. The predetermined number of times is, for example, two times.

Further, in the example shown in FIG. 4, when color printing is performed, all the surfaces of the continuous paper P corresponding to the surface on which the image is formed are formed regardless of which color of the inkjet head is used for printing. The inkjet head is made to perform preliminary ejection, but the present invention is not limited to this. The head control unit 15 may prevent the preliminary ejection of the inkjet head, which is not used for the color printing, from being executed even when the color printing is performed.

For example, when the printing instruction includes an instruction to perform color printing using yellow ink on the surface of the continuous paper P and not using magenta ink, the head control unit 15 reserves the first inkjet head 203Y of yellow. The ejection may be executed a predetermined number of times, and the magenta first inkjet head 203M may or may not execute the preliminary ejection a number of times less than the predetermined number of times. Here, the yellow first inkjet head 203Y is regarded as a first ejection unit that ejects the first color ink. Further, the magenta first inkjet head 203M is regarded as a second ejection unit that ejects the second color ink.

<Modification example 1 of preliminary discharge control processing>
Next, a modification 1 of the preliminary discharge control process will be described.
When the head control unit 15 acquires the instruction information from the instruction reception unit 11, it instructs the head information acquisition unit 12 to transmit the latest position information to the head control unit 15. Then, when the position information is acquired from the head information acquisition unit 12, the execution of preliminary ejection is controlled for each individual inkjet head based on the position information.

FIG. 5 is a flowchart showing the flow of the preliminary discharge control process in the first modification.
First, the head control unit 15 determines whether or not a printing instruction has been given (S201). While the negative result continues, the head control unit 15 repeats the determination operation in step 201.

If an affirmative result is obtained in step 201, the head control unit 15 determines whether or not the individual inkjet heads provided in the image forming apparatus 20 are located at the storage position (S202). Specifically, the head control unit 15 instructs the head information acquisition unit 12 to transmit the latest position information to the head control unit 15, and acquires the position information from the head information acquisition unit 12. Then, from the acquired position information, it is determined whether or not each inkjet head is located at the storage position.

When at least one of all the inkjet heads provided in the image forming apparatus 20 is located in the storage position (YES in step 202), the head control unit 15 is the inkjet head located in the storage position. (S203). Specifically, the head control unit 15 causes each of the inkjet heads located at the storage position among all the inkjet heads to perform preliminary ejection after removing the cap. On the other hand, the inkjet head that is not located in the storage position is not allowed to perform preliminary ejection.
Further, when none of the inkjet heads is located at the storage position (NO in step 202), the head control unit 15 does not cause any of the inkjet heads to perform preliminary ejection.

As described above, in the first modification, the head control unit 15 controls the execution of the preliminary ejection based on the positions of the individual inkjet heads.
In particular, in the first modification, the head control unit 15 is one when one inkjet head is located at a predetermined position and the other one inkjet head is located at a position different from the predetermined position. The inkjet head is not made to perform the preliminary ejection, and the other inkjet head is made to perform the preliminary ejection. Here, one inkjet head is regarded as a first ejection unit. Further, the other one inkjet head is regarded as a second ejection unit.
Further, the predetermined position is the print position.

<Modification example 2 of preliminary discharge control processing>
Next, a modification 2 of the preliminary discharge control process will be described.
Based on the position information continuously transmitted from the control unit 210 of the image forming apparatus 20, the head information acquisition unit 12 sets the inkjet head in the storage position for each of the individual inkjet heads provided in the image forming apparatus 20. Calculate the non-positioned time. Then, the time information indicating the time when the individual inkjet heads are not located at the storage position is transmitted to the head control unit 15.

The setting information acquisition unit 14 acquires page number information indicating the number of pages of continuous paper P on which an image is formed by warming up from the terminal device 30. Specifically, the setting information acquisition unit 14 obtains page number information from the terminal device 30 by setting the number of pages of continuous paper P on which the terminal device 30 is operated by the user and an image is formed by warming up. get. Then, the acquired page number information is transmitted to the head control unit 15.

When the head control unit 15 acquires instruction information from the instruction reception unit 11, it instructs the head information acquisition unit 12 to transmit the latest time information to the head control unit 15. In addition, the calculation unit 13 is instructed to transmit the ink amount information related to the latest printing to the head control unit 15. Here, the latest printing is printing performed according to the last printing instruction. Further, the setting information acquisition unit 14 is instructed to transmit the page number information related to the print setting when the latest printing is performed. Then, when the head control unit 15 acquires the time information, the ink amount information, and the page number information, the head control unit 15 controls the execution of preliminary ejection for each individual inkjet head based on the acquired information.

FIG. 6 is a flowchart showing the flow of the preliminary discharge control process in the second modification.
First, the head control unit 15 determines whether or not a printing instruction has been given (S301). While the negative result continues, the head control unit 15 repeats the determination operation in step 301.

When an affirmative result is obtained in step 301, the head control unit 15 has the number of pages of the continuous paper P on which the image is formed by the warm-up related to the latest printing is equal to or less than the predetermined second page number. Whether or not it is determined (S302). Specifically, the head control unit 15 acquires page number information from the setting information acquisition unit 14. Then, from the acquired page number information, it is determined whether or not the number of pages of the continuous paper P on which the image is formed by the warm-up related to the latest printing is equal to or less than the predetermined second page number. The predetermined number of second pages is a threshold value for determining whether or not preliminary ejection is necessary based on the amount of ink ejected from the inkjet head due to the warm-up related to the latest printing. The predetermined number of second pages is, for example, one.
If the amount of ink ejected from the inkjet head due to warm-up is large, new ink is supplied to the nozzle of the inkjet head accordingly. This new ink is less likely to cause ejection failure than the ink that is thickened as described above and is not suitable for image formation by continuing to accumulate in the nozzle. Therefore, an inkjet head filled with new ink has a lower need for preliminary ejection than an inkjet head containing ink that is not suitable for image formation. Therefore, in the present embodiment, the amount of ink ejected from the inkjet head due to warm-up is set as the execution condition for preliminary ejection.

If an affirmative result is obtained in step 302, the head control unit 15 causes the inkjet head to remove the cap and then execute preliminary ejection (S305).
The processing after step 302 is performed for each individual inkjet head.

On the other hand, when a negative result is obtained in step 302, the head control unit 15 determines whether or not the amount of ink ejected from the inkjet head by the latest printing is less than a predetermined amount (S303). ). Specifically, the head control unit 15 acquires ink amount information related to the latest printing from the calculation unit 13. Then, from the acquired ink amount information, it is determined whether or not the amount of ink ejected from the inkjet head to be determined by the latest printing is less than a predetermined amount. This predetermined amount is a threshold value for determining whether or not preliminary ejection is necessary based on the amount of ink ejected from the inkjet head in the latest printing. The predetermined amount is, for example, 10 ml.
If the amount of ink ejected from the inkjet head by printing is large, new ink is supplied to the nozzles of the inkjet head by that amount, so that ink ejection failure is less likely to occur. Therefore, in the present embodiment, the amount of ink ejected from the inkjet head by printing is set as an execution condition for preliminary ejection.
When a positive result is obtained in step 303, the head control unit 15 causes the inkjet head to remove the cap and then execute preliminary ejection (S305).

On the other hand, when a negative result is obtained in step 303, the head control unit 15 determines whether or not the time when the inkjet head is not located at the storage position is equal to or longer than a predetermined time (S304). Specifically, the head control unit 15 acquires the latest time information from the head information acquisition unit 12. Then, from the acquired time information, it is determined whether or not the time when the inkjet head is not located at the storage position is equal to or longer than a predetermined time. The predetermined time is a threshold value for determining whether or not preliminary ejection is required based on the time when the inkjet head is not covered with the cap. The predetermined time is, for example, one hour.
The ink in the inkjet head, which is located in the storage position and is covered with a cap, is less likely to cause ejection failure because it is harder to dry than the ink in the inkjet head without a cap. Therefore, in the present embodiment, the time when the inkjet head is not covered with the cap is set as the execution condition of the preliminary ejection.

If an affirmative result is obtained in step 304, the head control unit 15 causes the inkjet head to remove the cap and then execute the preliminary ejection (S305).
On the other hand, when a negative result is obtained in step 303, the head control unit 15 does not cause the inkjet head to be determined to perform preliminary ejection.

As described above, in the second modification, the head control unit 15 controls the execution of the preliminary ejection based on the state of each inkjet head. For example, the head control unit 15 controls the execution of preliminary ejection based on the amount of ink ejected from each of the individual inkjet heads of one inkjet head and the other one inkjet head by forming an image related to the latest printing. To do. Here, one inkjet head is regarded as a first ejection unit. Further, the other one inkjet head is regarded as a second ejection unit.

In the example shown in FIG. 6, the pre-discharge is not executed for the inkjet head that does not satisfy the predetermined conditions regarding the state of the inkjet head, but the present invention is not limited to this. The head control unit 15 may cause an inkjet head that does not satisfy a predetermined condition to perform preliminary ejection a smaller number of times than an inkjet head that satisfies a predetermined condition.

For example, in the head control unit 15, the time when one inkjet head is not located at the storage position reaches a predetermined time, and the time when the other one inkjet head is not located at the storage position is predetermined. If the time has not been reached, one inkjet head should be made to execute the preliminary ejection a predetermined number of times, and the other one inkjet head should be made to execute the preliminary ejection less than the predetermined number of times. It may be.

Further, for example, in the latest printing, the amount of ink ejected from one inkjet head does not reach a predetermined amount, and the amount of ink ejected from the other one inkjet head is a predetermined amount. When the above is reached, one inkjet head may be made to execute the preliminary ejection a predetermined number of times, and the other one inkjet head may be made to execute the preliminary ejection less than a predetermined number of times or may not be executed. ..

It should be noted that the "predetermined number of second page sheets", "predetermined amount", and "predetermined time" described above are set to different values for each individual inkjet head. May be good.
In addition, the value of the "predetermined number of second page pages" may differ depending on the amount ejected from the inkjet head for each pixel formation.
The "predetermined amount" is the integrated value of the amount of ink ejected from the inkjet head due to the latest printing and the amount of ink ejected from the inkjet head due to the warm-up related to the latest printing. May be set. That is, the "formation of an image related to the latest printing" includes not only the formation of an image by the latest printing but also the formation of an image by warm-up related to the latest printing.

The head control unit 15 may cause the inkjet head to perform preliminary ejection when the time during which the inkjet head is not located at the storage position after the completion of the latest printing is equal to or longer than a predetermined time. .. That is, the "time when the inkjet head is not in the storage position" includes the time when the inkjet head is not in the storage position after the latest printing is completed.

<Modification 3 of preliminary discharge control processing>
Next, a modification 3 of the preliminary discharge control process will be described.
The setting information acquisition unit 14 acquires execution information indicating execution of preliminary ejection for each individual inkjet head from the terminal device 30. Specifically, the setting information acquisition unit 14 acquires execution information from the terminal device 30 by setting an inkjet head in which the terminal device 30 is operated by the user to execute preliminary ejection. This execution information includes information indicating the number of times the preliminary discharge is executed. The number of executions is set for each individual inkjet head by operating the terminal device 30 by the user. The setting information acquisition unit 14 transmits the acquired execution information to the head control unit 15.

FIG. 7 is a flowchart showing the flow of the preliminary discharge control process in the modified example 3.
First, the head control unit 15 determines whether or not a printing instruction has been given (S401). While the negative result continues, the head control unit 15 repeats the determination operation in step 401.

If an affirmative result is obtained in step 401, the head control unit 15 determines whether or not the inkjet head is set to perform preliminary ejection (S402). Specifically, the head control unit 15 acquires execution information from the setting information acquisition unit 14. Then, from the acquired execution information, it is determined whether or not it is set to execute the preliminary ejection for each individual inkjet head provided in the image forming apparatus 20.

When there is at least one inkjet head set to execute the preliminary ejection (YES in step 402), the head control unit 15 causes the inkjet head to remove the cap, and then performs the preliminary ejection. Execute (S403). Specifically, the head control unit 15 is set for each of the inkjet heads provided in the image forming apparatus 20 and which are set to execute preliminary ejection. Execute the preliminary discharge of the number of executions.
On the other hand, when it is not set to execute the preliminary ejection to any of the inkjet heads (NO in step 402), the head control unit 15 does not execute the preliminary ejection to any of the inkjet heads.
As described above, in the modification 3, the head control unit 15 controls the number of times the preliminary ejection is executed for each individual inkjet head.

In the third modification, the setting information acquisition unit 14 acquires execution information separately from the print instruction, but the present invention is not limited to this.
For example, the instruction information may include execution information.

Although the embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear from the description of the scope of claims that the above-described embodiment with various modifications or improvements is also included in the technical scope of the present invention.

In the present embodiment, the execution of preliminary ejection is controlled for each individual inkjet head provided in the image forming apparatus 20, but the present embodiment is not limited to this. For example, at least two of the first inkjet heads 203 provided in the first image forming unit 201 may be controlled to execute the preliminary ejection.

Further, for example, the preliminary discharge control process shown in FIG. 4 and the preliminary discharge control process shown in FIG. 5 may be combined. Specifically, the head control unit 15 extracts an inkjet head to be preliminarily ejected by the process of step 202 shown in FIG. 5, and then selects the inkjet head located at the storage position among the extracted inkjet heads. Preliminary discharge may be performed. Then, among the extracted inkjet heads, the inkjet heads that are not located at the storage position may not be subjected to preliminary ejection. That is, when the head control unit 15 is instructed to print, even if the inkjet head is used for this printing, if the inkjet head is not located at the storage position, the head control unit 15 reserves the inkjet head. It is also possible not to execute the discharge.

Further, for example, the preliminary discharge control process shown in FIG. 5 and the preliminary discharge control process shown in FIG. 6 may be combined. Specifically, the head control unit 15 extracts an inkjet head to be preliminarily ejected by the processes of steps 302 to 304 in FIG. 6, and then, among the extracted inkjet heads, an inkjet located at a storage position. The head may be made to perform preliminary ejection. Then, among the extracted inkjet heads, the inkjet heads that are not located at the storage position may not be subjected to preliminary ejection. That is, even if the head control unit 15 is an inkjet head that is the target of pre-discharge based on the state of the inkjet head, if the inkjet head is not located at the storage position, the head control unit 15 pre-discharges to the inkjet head. May not be executed.

Further, the image forming apparatus 20 may be provided with an inkjet head different from the above-mentioned inkjet head. For example, the image forming apparatus 20 may be provided with an inkjet head that ejects metallic color ink. Then, the execution of preliminary ejection may be controlled for each individual inkjet head including the inkjet head that ejects the metallic color ink.

Further, in the present embodiment, an example in which an inkjet printer that forms an image on continuous paper P is used has been described, but the present invention is not limited to this.
For example, an inkjet printer that forms an image on cut paper may be used.

1 ... image forming system, 10 ... server device, 11 ... instruction receiving unit, 12 ... head information acquisition unit, 13 ... calculation unit, 14 ... setting information acquisition unit, 15 ... head control unit, 20 ... image forming device, 201 ... 1st image forming unit, 202 ... 1st driving unit, 203 ... 1st inkjet head, 204 ... 2nd image forming unit, 205 ... 2nd driving unit, 206 ... 2nd inkjet head

Claims (13)

An ejection means having a plurality of ejection portions provided with at least a first ejection portion and a second ejection portion for ejecting ink on the first surface of the recording material and forming an image on the recording material.
A control means for controlling the execution of preliminary ejection in which the ejection unit ejects ink before printing for each individual ejection unit of the first ejection unit and the second ejection unit.
An image forming system equipped with. The image forming system according to claim 1, wherein the control means controls the execution of the preliminary ejection from the printing instruction prior to printing. The first ejection unit ejects black ink and discharges black ink.
The second ejection unit ejects a color ink different from the black ink,
When the instruction includes an instruction to perform black-and-white printing on the first surface of the recording material, the control means causes the first ejection unit to execute the preliminary ejection a predetermined number of times, and causes the second ejection unit to execute the preliminary ejection a predetermined number of times. The image forming system according to claim 2, wherein the discharge unit executes or does not execute the preliminary discharge a number of times less than a predetermined number of times. To the plurality of ejection units, a third ejection unit that ejects the black ink onto the second surface of the recording material and a color ink of a color that is not used for black-and-white printing but is used for color printing are ejected to the second surface. Including the 4th discharge part
When the instruction includes an instruction to perform color printing on the second surface of the recording material, the control means predetermines the preliminary discharge to the third discharge portion and the fourth discharge portion. The image forming system according to claim 3, wherein the image forming system is executed a number of times. The first ejection unit ejects the first color ink.
The second ejection unit ejects the second color ink.
When the instruction includes an instruction to perform color printing using the first color ink on the first surface of the recording material and not using the second color ink, the control means is applied to the first ejection unit. The image forming system according to claim 2, wherein the preliminary discharge is executed a predetermined number of times, and the second discharge unit is executed or not executed a number of times less than the predetermined number of times. .. The discharge means can move the first discharge portion and the second discharge portion.
The image forming system according to claim 1, wherein the control means controls the execution of the preliminary discharge based on the positions of the individual discharge portions of the first discharge portion and the second discharge portion. When the first discharge unit is located at a predetermined position and the second discharge unit is located at a position different from the predetermined position, the control means performs the preliminary discharge to the first discharge unit. 6. The image forming system according to claim 6, wherein the second ejection unit executes the preliminary ejection without executing the above. The predetermined position is the position of the ejection portion where the ink adheres to the recording material when the ink is ejected from the individual ejection portions of the first ejection portion and the second ejection portion. The image forming system according to claim 7. The image forming system according to claim 1, wherein the control means controls the execution of the preliminary discharge based on the state of each discharge unit of the first discharge unit and the second discharge unit. The ejection means can move the first ejection unit and the second ejection unit to a storage position for storing the plurality of ejection units when the printing instruction is not received.
In the control means, the time when the first discharge unit is not located at the storage position reaches a predetermined time, and the time when the second discharge unit is not located at the storage position is predetermined. If the time has not been reached, the first discharge unit is made to execute the preliminary discharge a predetermined number of times, and the second discharge unit is made to execute the preliminary discharge a number of times less than the predetermined number of times. The image forming system according to claim 9, wherein the image forming system is not executed. The control means controls the execution of the preliminary ejection based on the amount of ink ejected from the individual ejection portions of the first ejection portion and the second ejection portion by forming an image relating to the latest printing. 9. The image forming system according to claim 9. In the latest printing, the control means does not reach a predetermined amount of ink ejected from the first ejection unit, and the amount of ink ejected from the second ejection unit is predetermined. When the specified amount is reached, the first discharge unit is made to execute the preliminary discharge a predetermined number of times, and the second discharge unit is made to execute or execute the preliminary discharge a number of times less than the predetermined number of times. The image forming system according to claim 11, wherein the image forming system is not allowed to be formed. The image forming system according to claim 1, wherein the control means controls the number of times the preliminary discharge is executed for each individual discharge unit of the first discharge unit and the second discharge unit.