JP6904014B2 - Image formation system and image formation method - Google Patents

Description

The present invention relates to an image forming system and an image forming method.

In recent years, an image forming system is required to output a printed matter having higher added value in addition to a conventional color image or the like. As a technique for increasing the added value of printed matter, for example, a technique of foil stamping in which toner is used as an adhesive to transfer foil to an image formed by toner formed on paper is known (for example, patent documents). 1).

By the way, in general printing, there is a control for stabilizing the image quality by forcibly discharging toner.

Japanese Unexamined Patent Publication No. 2013-238733

However, forcibly discharging the toner leads to wasteful consumption of the toner while stabilizing the image quality. In particular, in the invention described in Patent Document 1, since toner is used as an adhesive for foil stamping printing, when toner is consumed for image stability in addition to foil stamping printing, the amount of toner consumed is extremely high. There is a problem that it grows large.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image forming system and an image forming method for performing foil stamping printing while suppressing wasteful toner consumption.

The above object of the present invention is achieved by the following means.

(1) An image forming system capable of transferring foil to a foil pressing image formed by a toner to perform foil pressing printing, and an image forming unit for sequentially forming an image using the toner, and the image forming unit. It has a determination unit for determining whether or not it is necessary to forcibly discharge the toner, and the image forming unit can form a normal image and the foil pressing image, and the determination unit can form a normal image and the foil pressing image. An image forming system that does not forcibly discharge the toner when it is determined that it is necessary to forcibly discharge the toner together with the normal image, but there is an image for foil pressing that is subsequently formed.

(2) The image forming unit forms the image based on the image data included in the print job, and even when the determination unit determines that it is necessary to forcibly discharge the toner, the print job The image formation according to (1) above, wherein the toner is not forcibly discharged when the image data to be subsequently processed in the above includes the image data for foil pressing used for forming the image for foil pressing. system.

(3) Further having an acquisition unit for acquiring the amount of toner used, which is the amount of the toner used for forming the image based on the image data, the determination unit is the toner used acquired by the acquisition unit. The image forming system according to (2) above, wherein when the amount is less than a predetermined first threshold value, it is determined that the toner needs to be forcibly discharged.

(4) The amount of toner used, which is the amount of the toner used for forming the image based on the image data, is acquired for each of a plurality of regions divided by a predetermined width in the main scanning direction when forming the image. The determination unit further has an acquisition unit to be used, and when at least one of the toner amounts used in each region acquired by the acquisition unit is less than a predetermined second threshold value, the toner is said to be used. The image forming system according to (2) above, which determines that it is necessary to forcibly discharge the toner.

(5) When the determination unit determines that the toner needs to be forcibly discharged, the amount of the forced discharge toner, which is the amount of the toner that needs to be forcibly discharged to the image forming unit, is calculated. The image forming unit further includes a calculation unit, and the image forming unit forcibly forces the toner by the determination unit in the case where the image data for foil pressing is not included in the image data subsequently processed in the printing job. The image forming system according to (3) or (4) above, wherein when it is determined that the toner needs to be discharged to the toner, the toner of the forced discharge toner amount calculated by the calculation unit is forcibly discharged.

(6) The calculation unit further calculates the cumulative value of the forced discharge toner amount each time the forced discharge toner amount is calculated, and each time the image forming unit forms the foil pressing image, the foil pressing unit is used. The amount of toner used to form the image for printing is subtracted from the cumulative value, and the image forming unit uses the image data for foil pressing even when the image data subsequently processed in the print job includes the image data for foil pressing. The image forming system according to (5) above, wherein when the cumulative value calculated by the calculation unit is equal to or higher than a predetermined third threshold value at a predetermined timing, the toner is forcibly discharged.

(7) The toner further includes a selection unit for selecting the color of the toner used for forming the foil pressing image from the toners having a plurality of different colors, and the determination unit is used for each color of the toner. After determining whether or not it is necessary to forcibly discharge the toner, the acquisition unit acquires the amount of foil-pressed toner, which is the amount of the toner to be used for forming the foil-pressing image based on the foil-pressing image data. Then, when the determination unit determines that it is necessary to forcibly discharge the toners of a plurality of different colors, the calculation unit calculates the amount of the forced discharge toner for each color of the toner, and selects the toner. The unit compares the amount of the foil-pressed toner acquired by the acquisition unit with the amount of the forced discharge toner for each color of the toner calculated by the calculation unit, and at least used for forming the foil-pressing image. The above (5) or (6), wherein the color of one toner is selected, and the image forming unit forms the foil pressing image by using the toner of the color selected by the selecting unit. Image forming system.

(8) The selection unit preferentially uses the color of the toner, which has a larger amount of the forced discharge toner for each color of the toner calculated by the calculation unit, for forming the foil pressing image. The image forming system according to (7) above, which is selected as a color.

(9) The determination unit determines whether or not it is necessary to forcibly discharge each of the plurality of different colors of the toner, and the image forming unit determines whether or not the toners of the plurality of different colors need to be forcibly discharged by the determination unit. When it is determined that it is necessary to forcibly discharge the toner, the toners of the plurality of different colors are evenly used to form one of the above (1) to (6) for forming the foil pressing image. The image forming system described.

(10) A foil transfer unit that transfers a foil to a foil pressing image formed by a toner, and an image forming unit that can form a normal image and the foil pressing image by using the toner and sequentially forms an image. A step (a) of determining whether or not it is necessary to forcibly discharge the toner to the image forming unit, which is a method executed in an image forming system capable of performing foil stamping printing having the above. Even if it is determined in step (a) that it is necessary to forcibly discharge the toner together with the normal image, if there is a foil pressing image formed thereafter, the toner is not forcibly discharged. An image forming method including step (b).

According to the image forming system, even if it is determined that the toner needs to be forcibly discharged, the toner is not forcibly discharged if there is an image for foil pressing that is subsequently formed. The image forming system can reuse the toner that needs to be forcibly ejected to form the foil stamping image. Therefore, the image forming system can suppress wasteful toner consumption.

It is a figure which shows the schematic structure of the image formation system which concerns on one Embodiment of this invention. It is a block diagram which shows the schematic structure of the paper feed device, the image forming device, the foil pressing device, and the post-processing device. It is a block diagram which shows the functional structure of the control part of an image forming apparatus. It is a figure for demonstrating the forced discharge of toner. It is a figure for demonstrating the forced discharge of toner. It is a flowchart which shows the procedure of the process executed in an image formation system. 6 is a subroutine flowchart showing an example of a procedure for calculating the forced discharge toner width in steps S105 and S112 of FIG. 6 is a subroutine flowchart showing an example of a procedure for forming an image for stamping foil in step S111 of FIG. It is a figure for demonstrating an example of the relationship between the foil pressing toner amount and the cumulative forced discharge toner amount. It is a figure for demonstrating another example of the relationship between the foil pressing toner amount and the cumulative forced discharge toner amount. It is a figure for demonstrating the forced discharge of the toner of the modification 1. FIG. 6 is a subroutine flowchart showing another example of the procedure for calculating the forced discharge toner width in steps S105 and S112 of FIG. 6 is a subroutine flowchart showing another example of the procedure for forming an image for stamping foil in step S111 of FIG. It is a figure for demonstrating still another example of the relationship between the foil pressing toner amount and the cumulative forced discharge toner amount.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation and may differ from the actual ratios.

FIG. 1 is a diagram showing a schematic configuration of an image forming system according to an embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of a paper feeding device, an image forming device, a foil pressing device, and a post-processing device.

As shown in FIGS. 1 and 2, the image forming system 1 includes a paper feeding device 10, an image forming device 20, a foil pressing device 30, and a post-processing device 40. The paper feeding device 10, the image forming device 20, the foil pressing device 30, and the post-processing device 40 are connected in this order from the upstream side to the downstream side of the paper transport. Hereinafter, the image forming apparatus 20, the paper feeding apparatus 10, the foil pressing apparatus 30, and the post-processing apparatus 40 will be described in this order.

(Image forming apparatus 20)
The image forming apparatus 20 includes a control unit 21, a storage unit 22, a communication unit 23, an image processing unit 24, an operation panel 25, a paper feeding unit 26, an image forming unit 27, and a fixing unit 28. These are connected to each other via a bus for exchanging signals. The image forming apparatus 20 is an apparatus for forming an image by using a well-known image forming process such as an electrophotographic method.

The control unit 21 is a CPU (Central Processing Unit), and executes control of each of the above units and various arithmetic processes according to a program. The functional configuration of the control unit 21 will be described later.

The storage unit 22 includes a ROM (Read Only Memory) that stores various programs and various data in advance, a RAM (Random Access Memory) that temporarily stores programs and data as a work area, a hard disk that stores various programs and various data, and the like. Consists of.

The communication unit 23 is an interface for communicating with other devices, and transmits / receives set values, various signals necessary for operation timing control, and the like between the paper feeding device 10, the foil pressing device 30, and the post-processing device 40. To do. In addition, the communication unit 23 receives a print job or the like including image data from a user's PC (Personal Computer) or the like via a network.

The image processing unit 24 executes various image processing on the image data included in the print job as needed. The image processing unit 24, for example, performs rasterization processing or the like on the image data included in the print job received from the user's PC or the like to generate the image data in the bitmap format.

The operation panel 25 includes a touch panel, a numeric keypad, a start button, a stop button, and the like, displays various information, and is used for inputting various instructions.

The paper feed unit 26 includes a plurality of paper feed trays for storing the paper 50, which is a recording material used for printing, and feeds the paper 50 stored in the paper feed trays one by one to the image forming unit 27.

The image forming unit 27 uses at least one of a plurality of different color toners to form paper using a well-known image forming process such as an electrophotographic method including charging, exposure, developing, transfer and fixing steps. Form an image on 50. The image forming unit 27 sequentially forms an image based on the image data in the print job. The image forming unit 27 includes an image forming unit 271Y that forms an image of yellow (Y), an image forming unit 271M that forms an image of magenta (M), an image forming unit 271C that forms an image of cyan (C), and black. An image forming unit 271K for forming the image of (K) and a transfer belt 272 are provided.

The image forming units 271Y, 271M, 271C, and 271K include a photoconductor drum as an image carrier, and a charging unit, an optical writing unit, a developing device, and a photoconductor drum cleaning device (none of which are shown) arranged around the photoconductor drum. And each are provided. Each photoconductor drum is rotated at a predetermined speed by a drum motor. Each developing device contains a developer containing toners of each color of yellow, magenta, cyan and black. In the image forming units 271Y, 271M, 271C, and 271K, the optical writing unit writes an image information signal based on the image data of each color on the photoconductor drum, and forms a latent image based on the image information signal on the photoconductor drum. Then, the developing device develops the latent image and forms a toner image of each color, which is a visible image, on the photoconductor drum.

The image forming unit 27 may further include an image forming unit (not shown) other than the above-mentioned image forming units 271Y, 271M, 271C, and 271K. Specifically, the image forming unit 27 may include an image forming unit containing a spot color toner such as clear or white. By using a clear toner for expressing a glossy feeling and a transparent feeling and a white toner for forming a white image in the image forming unit 27, a printed matter having high added value can be output. The image forming unit containing these spot color toners has the same configuration as the image forming unit 271Y and the like.

The transfer belt 272 is an endless belt wound by a plurality of rollers and supported so as to be able to run. The toner images of each color formed on the photoconductor drum by the image forming units 271Y, 271M, 271C, and 271K are transferred onto the transfer belt 272, and the images transferred on the transfer belt 272 are transferred onto the paper 50. Toner.

The fixing unit 28 heat-fixes the image formed on the paper 50 by the image forming unit 27. The fixing portion 28 includes a pressure roller and a heating roller, and presses and heats the paper 50 on which the image is formed to weld the image onto the paper 50. The paper 50 on which the image is fixed by the fixing unit 28 is conveyed to the foil pressing device 30.

(Paper Feeding Device 10)
The paper feeding device 10 includes a control unit 11, a storage unit 12, a communication unit 13, and a paper feeding unit 14. These are connected to each other via a bus for exchanging signals. Since the control unit 11, the storage unit 12, and the communication unit 13 have the same functions as the control unit 21, the storage unit 22, and the communication unit 23 of the image forming apparatus 20, the description thereof will be omitted.

The paper feed unit 14 includes a plurality of paper feed trays, and feeds the paper 50 stored in the paper feed trays one by one to the image forming apparatus 20.

(Foil pressing device 30)
The foil pressing device 30 includes a control unit 31, a storage unit 32, a communication unit 33, and a foil transfer unit 34. These are connected to each other via a bus for exchanging signals. Since the control unit 31, the storage unit 32, and the communication unit 33 have the same functions as the control unit 21, the storage unit 22, and the communication unit 23 of the image forming apparatus 20, the description thereof will be omitted.

The foil transfer unit 34 transfers the foil to the foil pressing image formed by the toner to form the foil image. The foil transfer unit 34 uses toner as an adhesive by, for example, transporting a foil film sheet having a foil film formed on the surface of a base material, superimposing it on a foil stamping image on paper 50, and heating and pressure-welding it. Then, the foil is transferred to the image for stamping. The paper 50 to which the foil has been transferred by the foil transfer unit 34 is conveyed to the post-processing device 40.

(Post-processing device 40)
The post-processing device 40 includes a control unit 41, a storage unit 42, a communication unit 43, a post-processing unit 44, and a paper ejection unit 45. These are connected to each other via a bus for exchanging signals. Since the control unit 41, the storage unit 42, and the communication unit 43 have the same functions as the control unit 21, the storage unit 22, and the communication unit 23 of the image forming apparatus 20, the description thereof will be omitted.

The post-processing unit 44 executes post-processing such as stapling processing and punching processing on the paper 50 conveyed from the foil pressing device 30.

The paper discharge unit 45 discharges the paper 50 conveyed from the post-processing unit 44 to the outside of the post-processing device 40.

The paper feeding device 10, the image forming device 20, the foil pressing device 30, and the post-processing device 40 may include components other than the above-mentioned components, or may not include a part of the above-mentioned components. May be good.

As described above, the image forming system 1 of the present embodiment can perform foil stamping printing by transferring the foil to the foil stamping image formed by the toner. Hereinafter, the flow of the foil stamping printing process in the image forming system 1 will be described.

First, the image forming apparatus 20 receives a print job including image data used for forming an image for foil pressing (hereinafter referred to as "image data for foil pressing") from a user's PC or the like. Then, the image forming apparatus 20 forms a foil pressing image on the paper feeding unit 26 or the paper 50 fed from the paper feeding unit 14 of the paper feeding device 10. Subsequently, the foil pressing device 30 transfers the foil onto the paper 50 on which the foil pressing image is formed to form the foil image. Finally, the post-processing device 40 discharges the paper 50 on which the foil image is formed. The image forming system 1 outputs the printed matter on which the foil image is formed in this way.

When both the foil image and the normal image are formed on the paper 50, the image forming apparatus 20 forms the normal image on the paper 50 on which the foil image is formed. The image forming apparatus 20 accepts a print job including image data (hereinafter referred to as "normal image data") used for forming a normal image. Then, the image forming apparatus 20 forms a normal image on the paper 50 returned from the foil pressing apparatus 30 to the image forming apparatus 20 via the transport path. The image forming apparatus 20 may form a normal image on the paper 50 which has been temporarily discharged by the post-processing apparatus 40 and has been reset into the paper feeding unit 26 or the paper feeding unit 14 by the user. Subsequently, the foil pressing device 30 passes the paper 50 without transferring the foil. Finally, the post-processing device 40 discharges the paper 50 that has passed through the foil pressing device 30. The image forming system 1 outputs a printed matter in which both a foil image and a normal image are formed in this way.

Subsequently, the functional configuration of the control unit 21 of the image forming apparatus 20 will be described.

FIG. 3 is a block diagram showing a functional configuration of a control unit of the image forming apparatus.

In the present embodiment, the control unit 21 of the image forming apparatus 20 reads the program and executes the process, so that the job reception unit 211, the image control unit 212, the acquisition unit 213, the judgment unit 214, the calculation unit 215, and the selection unit Functions as 216.

The job reception unit 211 receives a print job received from a user's PC or the like via the communication unit 23. Further, the job reception unit 211 determines the type and number of image data included in the received print job. A print mode for instructing normal printing or foil stamping printing may be set for each image data via a user's PC, an operation panel 25, or the like.

The image control unit 212 controls the operation of the image forming unit 27, and causes the image forming unit 27 to form an image based on the image data. Further, the image control unit 212 determines for each image data whether or not the image formation timing, which is the timing for the image forming unit 27 to form an image, has been reached. Further, the image control unit 212 forcibly discharges the toner (hereinafter referred to as “forced discharge”) to the image forming unit 27 as needed. Under the control of the image control unit 212, the image forming unit 27 forms a toner image on the photoconductor drum and removes the toner image by the photoconductor drum cleaning device without transferring it onto the paper 50, thereby forcibly discharging the toner. Realize.

The acquisition unit 213 acquires the amount of toner used for forming the image (hereinafter, also referred to as “the amount of toner used”) based on the image data used for forming the image. In the present embodiment, "amount of toner used" may mean both "amount of toner used" and "amount of toner to be used" unless otherwise specified. That is, the description of "acquiring the amount of toner used" means "acquiring the amount of toner used for forming the image after forming the image" and "the amount of toner planned to be used for forming the image before forming the image". Can mean both of "getting". Further, in the present embodiment, the area of the image formed on the paper 50 can be acquired as the amount of toner used. In addition, the acquisition unit 213 acquires the coverage of the formed image from the acquired toner amount used.

The determination unit 214 determines for each color of the toner whether or not it is necessary for the image forming unit 27 to forcibly discharge the toner. If the amount of toner consumed by the image forming unit 27 is small, the toner stays in the developing device for a long time and is agitated more than necessary to deteriorate . When bets toner deteriorates, the development performance of the developing device is deteriorated, the quality of the toner image is deteriorated. Therefore, the determination unit 214 determines whether or not it is necessary to forcibly discharge the toner each time an image based on one image data is formed in order to stabilize the quality of the subsequent image.

The calculation unit 215 calculates the amount of toner that needs to be forcibly discharged by the image forming unit 27 (hereinafter referred to as “forced discharge toner amount”) for each toner color. In addition, the calculation unit 215 executes various arithmetic processes related to the forced discharge toner amount, such as calculating the cumulative value of the forced discharge toner amount (hereinafter referred to as “cumulative forced discharge toner amount”).

The selection unit 216 selects the color of the toner (hereinafter referred to as “foil stamping color”) used for forming the foil stamping image from a plurality of different color toners based on a predetermined condition. The selection unit 216 compares, for example, the amount of toner to be used for forming the foil pressing image with the cumulative forced discharge toner amount for each toner color, and selects at least one foil pressing color. Further, the selection unit 216 confirms the number of toner colors that can be used by the image forming unit 27 (that is, the number of image forming units included in the image forming unit 27) in order to select the foil stamping color.

In the following, forced ejection of toner will be described with reference to FIGS. 4 and 5.

4 and 5 are diagrams for explaining forced ejection of toner.

First, a case where a patch image showing forced ejection of toner is formed will be described with reference to FIG. In FIG. 4, a patch image of black (K) and cyan (C) toner is formed between the normal image A and the normal image B in order in the sub-scanning direction when the image is formed. The normal image A includes the letter "123" formed using black toner and a circle painted red using equal amounts of yellow (Y) and magenta (M) toner. There is.

As shown in FIG. 4, the toner is forcibly discharged by being used for forming a patch image. The patch image is formed outside the region where the normal image A and the normal image B are formed, for example, between the normal image A and the normal image B. The patch image can be formed in a strip shape having dimensions in the main scan direction and the sub scan direction when forming the image. In this embodiment, the area of the patch image can be calculated as the amount of forced discharge toner. Hereinafter, the dimension in the main scanning direction of the patch image is referred to as "forced ejection toner length", and the dimension in the sub-scanning direction is referred to as "forced ejection toner width". The forced discharge toner length is a fixed value, and may be, for example, a length corresponding to the maximum dimension in which toner can be discharged in the main scanning direction. The forced discharge toner length may be, for example, 330 mm. Since the forced discharge toner length is a fixed value, the forced discharge toner amount can be adjusted by adjusting the forced discharge toner width.

In FIG. 4, in order to stabilize the quality of the subsequent image including the normal image B, the cyan toner which is not used at all for forming the normal image A and the black toner which is used only in a small amount are forcibly discharged. There is. The forcibly discharged toner width of cyan is larger than the forced discharge toner width of black because more cyan toner, which is not normally used for forming the image A, is forcibly discharged than the black toner used in a small amount. On the other hand, the yellow and magenta toners are usually used in a sufficiently large amount for forming the image A, and therefore are not forcibly discharged. That is, it can be said that the forced discharge toner widths of yellow and magenta are zero.

Next, a case where a patch image showing forced ejection of toner is not formed will be described with reference to FIG. FIG. 5 is different from FIG. 4 in that the image following the normal image A is not the normal image B but the foil pressing image C. In FIG. 5, the same normal image A as in FIG. 4 is formed, but the cyan and black toners are not forcibly discharged. That is, it can be said that the forced discharge toner width of all colors is zero. As described above, the present embodiment is characterized in that the toner is not forcibly discharged when there is an image for foil pressing that is subsequently formed. Hereinafter, the processing of the image forming system 1 having such a feature will be described with reference to FIG.

FIG. 6 is a flowchart showing a procedure of processing executed in the image forming system.

The algorithm shown in the flowchart of FIG. 6 is stored as a program in the storage unit 22 of the image forming apparatus 20, and is executed by the control unit 21.

First, the control unit 21 determines whether or not the print job has been accepted by the job reception unit 211 (step S101).

When the print job is not accepted (step S101: NO), the control unit 21 waits until the print job is accepted.

When the print job is accepted (step S101: YES), the control unit 21 determines whether or not the print job includes image data for foil stamping as the job reception unit 211 (step S102).

When the foil pressing image data is not included (step S102: NO), that is, when only the normal image data is included, the control unit 21 proceeds to the process of step S103. Then, the control unit 21 determines, as the image control unit 212, whether or not the image formation timing based on the first normal image data among the unoutput normal image data included in the print job has arrived (step S103). ..

When the image formation timing has not been reached (step S103: NO), the control unit 21 waits until the image formation timing is reached.

When the image formation timing is reached (step S103: YES), the control unit 21 causes the image forming unit 27 to form a normal image based on the normal image data as the image control unit 212 (step S104). Then, the control unit 21 proceeds to the process of calculating the forced discharge toner width in step S105. The details of the process in step S105 will be described later with reference to FIG. 7, but the control unit 21 forces discharge toner width for each toner color based on the amount of toner used to form the normal image in step S104. Is calculated.

Subsequently, the control unit 21 causes the image control unit 212 to forcibly discharge the toner corresponding to the forced discharge toner width calculated in step S105 to the image forming unit 27 (step S106). That is, the control unit 21 causes the image forming unit 27 to form a patch image having the forced discharge toner width calculated in step S105.

Subsequently, the control unit 21 determines, as the job reception unit 211, whether or not the normal image data to be processed after the print job is included (step S107).

When the normal image data is included (step S107: YES), the control unit 21 returns to the process of step S103. Then, the control unit 21 repeats the processes of steps S103 to S107 until the print job does not include the unoutput normal image data (step S107: NO). The control unit 21 calculates the forced discharge toner width each time a normal image is formed, and forcibly discharges the toner of a color whose forced discharge toner width exceeds zero. That is, it can be said that the processes of steps S103 to S107 are processes in which the forced discharge of toner is permitted.

On the other hand, in step S102, when the print job includes image data for foil pressing (step S102: YES), the control unit 21 proceeds to the process of step S108. Then, the control unit 21 determines, as the image control unit 212, whether or not the image formation timing based on the first image data of the unoutput image data included in the print job has been reached (step S108).

When the image formation timing has not been reached (step S108: NO), the control unit 21 waits until the image formation timing is reached.

When the image formation timing is reached (step S108: YES), the control unit 21, as the image control unit 212, determines whether or not the image to be formed is a normal image (step S109).

When the image to be formed is a normal image (step S109: YES), the control unit 21 causes the image forming unit 27 to form a normal image based on the normal image data as the image control unit 212 (step S110).

When the image to be formed is not a normal image (step S109: NO), that is, when it is a foil pressing image, the control unit 21 proceeds to the process of forming the foil pressing image in step S111. The details of the process of step S111 will be described later with reference to FIG. 8, but the control unit 21 selects the foil stamping color based on a predetermined condition, and the foil stamping image using the foil stamping color is sent to the image forming unit 27. To form.

Subsequently, the control unit 21 proceeds to the process of calculating the forced discharge toner width in step S112. The process of step S112 is a process common to the process of step S105. The details of the processing in step S112 will be described later with reference to FIG. 7, but the control unit 21 forces the toner to be discharged for each color of the toner based on the amount of toner used to form the image in step S110 or S111. Calculate the width.

Subsequently, the control unit 21 determines, as the job reception unit 211, whether or not the foil pressing image data to be processed after the print job is included (step S113).

When the image data for foil pressing is included (step S113: YES), the control unit 21 proceeds to the process of step S114. Then, the control unit 21, as the calculation unit 215, calculates the amount of forced discharge toner for each color of the toner based on the forced discharge toner width calculated in step S112 (step S114). As described above, in the present embodiment, the area of the patch image can be calculated as the amount of forced discharge toner. Therefore, the control unit 21 can calculate the forced discharge toner amount by multiplying the predetermined forced discharge toner length (for example, 330 mm) by the forced discharge toner width calculated in step S112.

Further, as will be described later, the control unit 21 may repeat the process of step S114 thereafter. Therefore, the control unit 21 calculates the cumulative forced discharge toner amount for each color of the toner by accumulating each time the forced discharge toner amount is calculated (step S114). When the control unit 21 executes the process of step S114 for the first time, the cumulative forced discharge toner amount becomes the same value as the forced discharge toner amount.

After step S114, the control unit 21 returns to the process of step S108. Then, the control unit 21 repeats the processes of steps S108 to S114 until the print job does not include the unoutput image data for stamping foil (step S113: NO). The control unit 21 calculates the forced discharge toner width each time an image is formed, but does not force the toner to be discharged. That is, it can be said that the processes of steps S108 to S114 are processes in a state in which forced discharge of toner is prohibited.

On the other hand, in step S113, when the foil pressing image data to be processed after the print job is not included (step S113: NO), the control unit 21 proceeds to the process of step S106. Then, the control unit 21 causes the image control unit 212 to forcibly discharge the toner corresponding to the forced discharge toner width calculated in step S112 to the image forming unit 27 (step S106). Further, the control unit 21 proceeds to the process of step S107, and repeats the processes of steps S103 to S107 until the print job does not include the unoutput normal image data (step S107: NO).

When the image data to be processed after the print job is not included (step S107: NO), that is, when all the image data included in the print job is output, the control unit 21 performs the process in step S115. move on. Then, the control unit 21 determines, as the determination unit 214, whether or not the cumulative forced discharge toner amount is equal to or greater than a predetermined toner amount (third threshold value) for each toner color (step S115). ^{The predetermined amount of toner may be, for example, 124,740 mm 2} , which corresponds to the area of A3 paper size (297 mm × 420 mm), or may be set by the user.

When the cumulative forced discharge toner amount is equal to or more than a predetermined toner amount (step S115: YES), the control unit 21, as the image control unit 212, applies toner corresponding to the predetermined toner amount to the image forming unit 27 for each toner color. (Step S116). The image forming unit 27 forcibly discharges the toner outside the region where the image based on the image data is formed. When the predetermined amount of toner is, for example, 124,740 mm ² , the control unit 21 ^{forcibly discharges 124,740 mm 2} minutes of toner at a time. ^{The control unit 21 may forcibly discharge 124,740 mm 2} minutes of toner by forming an image having a size of 297 mm × 420 mm, which corresponds to the size of A3 size, on the image forming unit 27, for example.

As described above, the control unit 21 prohibits forced ejection of toner while the print job includes unoutput image data for stamping foil. For example, even if only the last image data in the print job is the foil stamping image data, the control unit 21 continues to prohibit the forced discharge of the toner until the foil stamping image data is processed. In this case, even if the control unit 21 causes the image forming unit 27 to form a foil pressing image using toner that needs to be forcibly discharged, there is a high possibility that a large cumulative amount of forcibly discharged toner remains. Therefore, after all the image data included in the print job is output, the control unit 21 forcibly discharges the toner when the cumulative forced discharge toner amount is too large.

On the other hand, in step S115, when the cumulative forced discharge toner amount is not equal to or more than the predetermined toner amount (step S115: NO), that is, when it is less than the predetermined toner amount, the control unit 21 ends the process as it is.

Subsequently, the process of calculating the forced discharge toner width in steps S105 and S112 will be described in detail.

FIG. 7 is a subroutine flowchart showing an example of the procedure for calculating the forced discharge toner width in steps S105 and S112 of FIG.

First, the control unit 21 acquires, as the acquisition unit 213, the amount of toner used for forming each image in step S104, step S110 or step S111 for each toner color based on each image data (step). S201). As described above, in the present embodiment, the area of the formed image can be acquired as the amount of toner used. Then, the control unit 21 acquires the image coverage for each toner color based on the amount of toner used as the acquisition unit 213 (step S202).

Subsequently, the control unit 21 determines, as the determination unit 214, whether or not the coverage acquired in step S202 is less than a predetermined coverage (first threshold value) for each toner color (step S203). The predetermined coverage may be, for example, 5% or may be set by the user. The control unit 21 determines whether or not the amount of toner used is less than the predetermined amount of toner by determining whether or not the coverage is less than the predetermined coverage. The control unit 21 may directly determine the amount of toner used instead of determining the coverage.

When the coverage is less than the predetermined coverage (step S203: YES), the control unit 21 determines that the toner needs to be forcibly discharged as the determination unit 214 (step S204). Then, the control unit 21 calculates the forced discharge toner width for each color of the toner as the calculation unit 215 based on the coverage (step S205). After that, the control unit 21 returns to the process of FIG.

For example, when the predetermined coverage is 5% and the reference value of the paper length in the sub-scanning direction is 210 mm, the control unit 21 calculates the forced discharge toner width based on the following formula.

^{Here, "9.45" in the formula is 3118.5 mm 2} , which corresponds to the area of 5% coverage of the A4 paper size (210 mm × 297 mm), divided by 330 mm, which is a predetermined toner length of the patch image. The value. That is, "9.45" is a value corresponding to the forced discharge toner width of the patch image having an area corresponding to the area of 5% coverage of A4 size. Further, "210" corresponds to the paper length in the sub-scanning direction when the A4 paper is placed horizontally. In the formula, the unit of the forced discharge toner width and the paper length in the sub-scanning direction is mm, and the unit of coverage is%.

Here, the relationship between the coverage and the forced discharge toner width when the paper length in the sub-scanning direction is 210 mm is shown in the following table.

That is, in order to stabilize the quality of the subsequent image, the control unit 21 controls the forced discharge toner width so that ^{the total of the used toner amount and the forced discharge toner amount is 3118.5 mm 2 or more for each paper transport distance of 210 mm.} To adjust.

On the other hand, in step S203, when the coverage is not less than the predetermined coverage (step S203: NO), that is, when the coverage is equal to or more than the predetermined coverage, the control unit 21 proceeds to the process of step S206. Then, the control unit 21 determines that it is not necessary to forcibly discharge the toner as the determination unit 214 (step S206). In this case, it corresponds to the case ^{where 3118.5 mm 2} is achieved only by the amount of toner used. Further, the control unit 21 calculates the forced discharge toner width as 0 as the calculation unit 215 (step S207), and returns to the process of FIG.

After returning to the process of FIG. 6, the control unit 21 forcibly discharges the toner corresponding to the forced discharge toner width to the image forming unit 27 in step S106, and in step S114, the forced discharge toner amount is calculated from the forced discharge toner width. To calculate. When the forced discharge toner width is calculated to be 0 in step S207, the control unit 21 does not force the image forming unit 27 to discharge the toner in step S106.

Subsequently, the process of forming the image for stamping the foil in step S111 will be described in detail.

FIG. 8 is a subroutine flowchart showing an example of a procedure for forming an image for foil pressing in step S111 of FIG.

The control unit 21 first determines whether or not the foil stamping color is specified by the user (step S301). The foil stamping color can be specified, for example, via the user's PC or the operation panel 25.

When the foil stamping color is specified (step S301: YES), the control unit 21 selects the color specified by the user as the foil stamping color as the selection unit 216 (step S302).

When the foil stamping color is not specified (step S301: NO), the control unit 21, as the calculation unit 215, has executed the process of step S114 at least once by this point, and has calculated the cumulative forced discharge toner amount? Is determined (step S303).

When the cumulative forced discharge toner amount has not been calculated (step S303: NO), the control unit 21 selects a predetermined color as the foil stamping color as the selection unit 216 (step S304). The predetermined color may be the color initially set as the foil stamping color, or the color of the toner having the largest amount of toner remaining in the image forming apparatus 20.

When the cumulative forced discharge toner amount is calculated (step S303: YES), the control unit 21 confirms the cumulative forced discharge toner amount for each color of the toner calculated in step S114 as the calculation unit 215 (step S305). ). Then, the control unit 21 acquires, as the acquisition unit 213, the amount of toner to be used for forming the foil pressing image (hereinafter, referred to as “foil pressing toner amount”) based on the foil pressing image data (step S306). In the present embodiment, the area of the foil pressing image formed on the paper 50 can be acquired as the amount of foil pressing toner. The control unit 21 may execute the processes in steps S305 and S306 by changing the order of processing.

Subsequently, the control unit 21, as the selection unit 216, has the maximum cumulative forced discharge toner amount of the cumulative forced discharge toner amount for each color of the toner confirmed in step S305, which is the foil pressing toner amount acquired in step S306. It is determined whether or not the above is the case (step S307). Here, it is assumed that the cumulative forced discharge toner amount of yellow is 80 mm ² , the cumulative forced discharge toner amount of magenta is 50 mm ² , the cumulative forced discharge toner amount of cyan is 30 mm ² , and the cumulative forced discharge toner amount of black is 20 mm ^2. To do. In this case, the control unit 21 determines whether or not the cumulative forced discharge toner amount of yellow 80 mm ² is equal to or larger than the foil pressing toner amount.

When the maximum cumulative forced discharge toner amount is equal to or greater than the foil pressing toner amount (step S307: YES), the control unit 21 selects the toner color having the maximum cumulative forced discharge toner amount as the foil pressing color as the selection unit 216. (Step S308).

When the maximum cumulative forced discharge toner amount is not equal to or more than the foil pressing toner amount (step S307: NO), that is, when it is less than the foil pressing toner amount, the control unit 21 proceeds to the process of step S309. Then, the control unit 21 sets the set value T to 2 (step S309). The set value T is a value indicating the number of toner colors that can be used for forming the foil pressing image.

Subsequently, in the control unit 21, as the selection unit 216, whether the set value T is equal to or less than the number of toner colors that can be used by the image forming unit 27 (that is, the number of image forming units included in the image forming unit 27). It is determined whether or not (step S310). For example, when the control unit 21 executes the process of step S310 for the first time and the image forming unit 27 includes four image forming units 271Y, 271M, 271C, and 271K, the set value T is used for the control unit 21. It can be determined that the number is less than or equal to the number of possible toner colors. When the image forming unit 27 includes an image forming unit containing the spot color toner, the number of colors of the toner that can be used includes the number of colors of the spot color toner.

When the set value T is equal to or less than the number of available toner colors (step S310: YES), the control unit 21 proceeds to the process of step S311. Then, the control unit 21 calculates, as the calculation unit 215, the total value of the cumulative forced discharge toner amount up to the Tth among the cumulative forced discharge toner amounts for each toner color (step S311). For example, when the process of step S311 is executed for the first time, the control unit 21 determines the second largest cumulative forced discharge toner amount, that is, the maximum cumulative forced discharge toner amount and the second largest cumulative forced discharge toner amount. Sum. Here, it is assumed that the cumulative forced discharge toner amount of yellow is 80 mm ² , the cumulative forced discharge toner amount of magenta is 50 mm ² , the cumulative forced discharge toner amount of cyan is 30 mm ² , and the cumulative forced discharge toner amount of black is 20 mm ^2. To do. Control unit 21, when first run the process in step S311 in this condition, the 130 mm ² which is the sum of the 50 mm ² of the yellow 80 mm ² and magenta, is calculated as the sum value.

Subsequently, the control unit 21 determines, as the selection unit 216, whether or not the total value calculated in step S311 is equal to or greater than the amount of foil-pressed toner acquired in step S306 (step S312).

If the total value is not equal to or greater than the amount of foil pressing toner (step S312: NO), that is, if it is less than the amount of foil pressing toner, the control unit 21 proceeds to the process of step S313. Then, the control unit 21 increases the set value T to T + 1 and resets it (step S313). The control unit 21 sets the set value T to 3, for example, when the process of step S313 is executed for the first time. After that, the control unit 21 returns to the process of step S310. The control unit 21 of steps S310 to S313 until the set value T is not less than or equal to the number of available toner colors (step S310: NO) or the total value is equal to or more than the foil pressing toner amount (step S312: YES). Repeat the process.

When the total value is equal to or greater than the foil pressing toner amount (step S312: YES), the control unit 21 selects, as the selection unit 216, the color of the toner having the largest cumulative forced discharge toner amount up to the Tth as the foil pressing color (step S312: YES). S314). Control unit 21, for example, in step S311, if you have to calculate the 130 mm ² which is the sum of the 50 mm ² of the yellow 80 mm ² and magenta as the total value, selects both the yellow and magenta as foil color. When the total value exceeds the foil stamping toner amount, the control unit 21 may select a toner color having a larger cumulative forced discharge toner amount as the foil stamping color to be preferentially used.

On the other hand, in step S310, if the set value T is not less than or equal to the number of available toner colors (step S310: NO), that is, if it exceeds the number of available toner colors, the control unit 21 processes the process in step S315. Proceed to. Then, the control unit 21 selects, as the selection unit 216, the color of all the toners whose cumulative forced discharge toner amount exceeds 0 (having the cumulative forced discharge toner amount) as the foil pressing color (step S315).

Subsequently, the control unit 21 causes the image forming unit 27 to form a foil stamping image using the foil stamping color toner selected in steps S302, S304, S308, S314 or S315 as the image control unit 212 (step S316). ).

For example, when the foil stamping color is selected in step S302, the control unit 21 causes the image forming unit 27 to form a foil stamping image using the toner of the color specified by the user.

When the foil stamping color is selected in step S304, the control unit 21 causes the image forming unit 27 to form a foil stamping image using toner of a predetermined color.

When the foil stamping color is selected in step S308, the control unit 21 causes the image forming unit 27 to form a foil stamping image using the toner of the color having the maximum cumulative forced discharge toner amount.

When the foil stamping color is selected in step S314, the control unit 21 causes the image forming unit 27 to apply toner of a color having a large cumulative forced discharge toner amount up to the T-th to an amount equal to or less than the cumulative forced discharge toner amount. Form the foil stamping image used for each. Specifically, for example, when yellow and magenta are selected as the foil stamping colors, the control unit 21 causes the image forming unit 27 to form a part of the foil stamping image with yellow toner, and the remaining part is magenta. It is formed by the toner of. The control unit 21 may cause the image forming unit 27 to form a foil pressing image using toners of different colors for each of a plurality of regions divided in the sub-scanning direction.

When the foil stamping color is selected in step S315, the control unit 21 causes the image forming unit 27 to form a foil stamping image using toners of all colors having a cumulative forced discharge toner amount. However, when the process of step S315 is executed, it corresponds to the case where the foil pressing toner amount cannot be secured even if the cumulative forced discharge toner amounts of the toners of all colors are totaled. Therefore, the control unit 21 causes the image forming unit 27 to use the toners of all colors having the cumulative forced discharge toner amount for each cumulative forced discharge toner amount, and at any one of the toner amounts insufficient with respect to the foil pressing toner amount. Toner of the color of is supplemented to form a foil stamping image. The toner color for compensating for the insufficient amount of toner may be a color selected by the user, a color initially set as a foil stamping color, or a color of the toner having the largest amount of remaining toner in the image forming apparatus 20.

Subsequently, the control unit 21, as the acquisition unit 213, acquires the amount of toner used in step S316 for each toner color, and the calculation unit 215 obtains the amount of toner used for each color of toner. Subtract from the quantity (step S317). Then, the control unit 21 returns to the process of FIG. In the present embodiment, as described above, the area of the formed foil pressing image can be acquired as the foil pressing toner amount, and the area of the patch image can be calculated as the forced discharge toner amount. Therefore, the control unit 21 can process the foil pressing toner amount and the cumulative forced discharge toner amount as numerical values having the same area unit. However, when the foil stamping color is selected in step S304, it corresponds to the case where the cumulative forced discharge toner amount has not been calculated, so the control unit 21 omits the process of step S317. Further, even when the foil stamping color is selected in step S302 and the cumulative forced discharge toner amount is not calculated, the control unit 21 omits the process of step S317.

Hereinafter, the above processing will be further described with reference to FIGS. 9 and 10.

FIG. 9 is a diagram for explaining an example of the relationship between the amount of foil pressed toner and the amount of cumulative forced discharge toner. FIG. 10 is a diagram for explaining another example of the relationship between the amount of foil pressed toner and the amount of cumulative forced discharge toner.

FIG. 9A shows the cumulative forced discharge toner amount and the foil stamping toner amount before the foil stamping image is formed. Here, it is assumed that the cumulative forced discharge toner amount of yellow is 80 mm ² , the cumulative forced discharge toner amount of magenta is 50 mm ² , the cumulative forced discharge toner amount of cyan is 30 mm ² , and the cumulative forced discharge toner amount of black is 20 mm ^2. To do. Then, it is assumed that the amount of foil-pressing toner to be used for forming the foil-pressing image is 150 mm ^2. Hereinafter, the procedure for selecting the foil stamping color will be described on the premise of the condition of the toner amount shown in FIG. 9A.

^{First, the control unit 21 determines whether or not the yellow 80 mm 2} which is the maximum cumulative forced discharge toner amount is equal to or more than the foil pressing toner amount. Since the cumulative forced discharge toner amount of yellow is less than the foil stamping toner amount, the control unit 21 cannot select the foil stamping color at this point.

Subsequently, the control unit 21 calculates the total value of the cumulative forced discharge toner amount that is the second largest. That is, the control unit 21 calculates 130 mm ^{2, which is the sum of 80 mm 2 of} yellow, which is the maximum cumulative forced discharge toner amount, ^{and 50 mm 2 of} magenta, which is the second largest cumulative forced discharge toner amount, as a total value. .. Then, the control unit 21 determines whether or not the total value is equal to or greater than the amount of foil pressing toner. Since the total value of the cumulative forced discharge toner amounts of yellow and magenta is less than the foil stamping toner amount, the control unit 21 cannot select the foil stamping color even at this point.

Subsequently, the control unit 21 calculates the total value of the cumulative forced discharge toner amount that is the third largest. That is, the control unit 21 has the maximum cumulative forced discharge toner amount of 80 mm ² for yellow, the second largest cumulative forced discharge toner amount of 50 mm ^2, and the third largest cumulative forced discharge toner amount. the 160 mm ² which is the sum of the 30 mm ² of cyan, is calculated as the sum value. Then, the control unit 21 determines whether or not the total value is equal to or greater than the amount of foil pressing toner. Since the total value of the cumulative forced discharge toner amounts of yellow, magenta, and cyan is equal to or greater than the foil stamping toner amount, the control unit 21 selects yellow, magenta, and cyan as the foil stamping colors. In this way, the control unit 21 adds the cumulative forced discharge toner amount until the total value becomes equal to or more than the foil stamping toner amount, and selects the foil stamping color.

FIG. 9B shows the remaining amount of the cumulative forced discharge toner amount after the foil pressing image is formed on the premise of the condition of the toner amount of FIG. 9A. The cumulative forced discharge toner amount of yellow and magenta is 0 mm ² , the cumulative forced discharge toner amount of cyan is 10 mm ² , and the cumulative forced discharge toner amount of black is 20 mm ² . The total value of the cumulative forced discharge toner amounts of yellow, magenta, and cyan before forming the foil stamping image was 10 mm ² larger than the foil stamping toner amount. , The cumulative amount of forced discharge toner of cyan remains ^{10 mm 2.}

Further, FIG. 10A shows the cumulative forced discharge toner amount and the foil stamping toner amount before the foil stamping image is formed. The cumulative forced discharge toner amount is the same as in FIG. 9 (a), but the foil pressing toner amount is 50 mm ² larger than that in FIG. 9 (a). In this case, the total amount of the cumulative forced discharge toners of all the colors of yellow, magenta, cyan, and black does not exceed the amount of the foil pressing toner, so the control unit 21 selects all the colors as the foil pressing colors.

FIG. 10B shows the remaining amount of the cumulative forced discharge toner amount after the foil pressing image is formed on the premise of the condition of the toner amount of FIG. 10A. The cumulative amount of forced discharge toner for all colors is 0 mm ² . ^{Further, the toner amount of 20 mm 2} , which is insufficient with respect to the amount of the foil stamping toner, is supplemented by, for example, the toner of the color initially set as the foil stamping color.

As described above, according to the image forming system 1, even if it is determined that the toner needs to be forcibly discharged, the toner is not forcibly discharged if there is an image for foil pressing that is subsequently formed. The image forming system 1 can reuse the toner that needs to be forcibly discharged to form the foil pressing image. Therefore, the image forming system 1 can suppress wasteful toner consumption.

Further, the image forming system 1 does not forcibly discharge the toner when the image data subsequently processed in the print job includes the foil pressing image data used for forming the foil pressing image. Therefore, the image forming system 1 can determine whether or not forced discharge of toner is necessary based on the image data.

Further, the image forming system 1 determines that it is necessary to forcibly discharge the toner when the amount of toner used is less than a predetermined threshold value. Therefore, the image forming system 1 can appropriately determine whether or not it is necessary to forcibly discharge the toner according to the amount of toner used in the image formed immediately before.

Further, when the image forming system 1 determines that it is necessary to forcibly discharge the toner, the image forming system 1 calculates the amount of the forcibly discharged toner. Then, the image forming system 1 forcibly discharges the toner corresponding to the amount of the forced discharge toner when the foil pressing image data to be processed after the print job is not included. As a result, the image forming system 1 can stabilize the quality of the subsequent image.

Further, the image forming system 1 acquires the foil pressing toner amount, calculates the forced discharge toner amount for each toner color, compares the foil pressing toner amount with the forced discharge toner amount for each toner color, and compares the foil pressing toner amount with the forced discharge toner amount for each toner color. Select. Then, the image forming system 1 forms an image for foil pressing by using the toner of the selected color. Therefore, the image forming system 1 can form an image for foil pressing by selectively using the toner that needs to be forcibly discharged.

Further, the image forming system 1 selects a color of toner having a larger amount of forced discharge toner as a foil stamping color to be used preferentially. As a result, the image forming system 1 can preferentially use the toner that has remained in the developing device for a long time, and the quality of the subsequent image can be stabilized.

In the above embodiment, an example of the processing procedure of the image forming system 1 has been described. However, this embodiment is not limited to this. The following various changes and improvements are possible.

It has been explained that the image forming system 1 determines in step S115 whether or not the cumulative forced discharge toner amount is equal to or more than a predetermined toner amount after all the image data included in the print job is output. However, this embodiment is not limited to this. The image forming system 1 may execute the same processing as in steps S115 and S116 at predetermined timings, for example, at predetermined times or every time a predetermined number of image data are processed. As a result, the image forming system 1 is forced to discharge the toner at a predetermined timing even when the image data for foil pressing to be processed after the print job is included, and the quality of the image is always stabilized.

Further, it has been explained that the image forming system 1 does not forcibly eject the toner when the image data for foil pressing to be processed after the print job is included. However, this embodiment is not limited to this. The image forming system 1 may be controlled so as not to forcibly eject the toner even when the foil pressing image is included in any of the plurality of print jobs received from the user's PC or the like. That is, for example, even if the print job being processed does not include the image data for foil pressing, the image forming system 1 does not forcibly eject the toner when the print job waiting to be processed contains the image data for foil pressing. It may be controlled by. As a result, the image forming system 1 can further suppress wasteful toner consumption.

Further, the image forming system 1 may be controlled so as not to forcibly discharge the toner only when there is foil pressing image data immediately after the image data being processed in the print job. That is, the image forming system 1 forces the toner if there is no foil pressing image data immediately after the image data being processed even if the foil pressing image data is included two or more ahead of the image data being processed. It may be controlled to discharge. Further, the image forming system 1 may be controlled to forcibly discharge the toner when the image data for foil pressing is not included in the image data that follows the image data being processed within a predetermined number. As a result, the image forming system 1 can forcibly discharge toner as necessary even when the print job includes unoutput image data for foil stamping, and can stabilize the image quality.

Further, in the image forming system 1, when the ratio of the foil stamping image data to the image data included in the print job is less than a predetermined ratio, even if the print job includes unoutput foil stamping image data. , The toner may be controlled to be forcibly discharged.

Further, the image forming system 1 may be executed by changing the order of the processes of steps S104 and S105. That is, the image forming system 1 does not calculate the amount of toner used after forming the normal image and then calculate the forced discharge toner width, but instead uses the amount of toner scheduled to be used for forming the normal image as the normal image data. A normal image may be formed after calculating based on the calculation and calculating the forced discharge toner width. Similarly, when the image formed in step S109 is a normal image, the image forming system 1 may execute the processes in steps S110 and S112 in a different order.

Further, although it has been explained that the image forming system 1 acquires the area of the image to be formed as the amount of toner used, the present embodiment is not limited to this. The image forming system 1 may acquire the amount of toner actually used by the developing device as the amount of toner used.

Hereinafter, modifications of the present embodiment will be described with reference to the drawings.

(Modification example 1)
In the above embodiment, it has been described that the image forming system 1 determines whether or not it is necessary to forcibly discharge the toner based on the amount of toner used for forming the entire image. In the first modification, it will be described that the image forming system 1 determines whether or not it is necessary to forcibly discharge the toner based on the amount of the toner used for forming a part of the image.

In the above embodiment, if the amount of toner consumed by the image forming unit 27 is small, the toner stays in the developing device for a long time and is agitated more than necessary to deteriorate, so that the quality of the toner image deteriorates. However, the problem that occurs when the toner consumption is low is not limited to this. For example, if the amount of toner consumed is small, new toner cannot be supplied to the image forming unit, which may cause mechanical damage to the image forming unit 27. In the first modification, in order to avoid such mechanical damage, forcibly ejecting the toner will be described.

FIG. 11 is a diagram for explaining forced discharge of toner according to the first modification.

Also in the first modification, a patch image showing the forced discharge of the toner can be formed as in the above embodiment. In FIG. 11, between the normal image D and the normal image E, patches with black (K), cyan (C), magenta (M), and yellow (Y) toners are applied in this order in the sub-scanning direction when the image is formed. The image is formed. The patch image of each color has a different forced discharge toner width for each region in which a predetermined toner length (for example, 330 mm) is divided into eight in the main scanning direction. Further, the forced discharge toner width of each region of the patch image is calculated based on the amount of toner used for each region in which the normal image D is divided into eight in the main scanning direction so as to correspond to each region of the patch image. .. Hereinafter, as shown in FIG. 11, each region is referred to as regions 1 to 8. The normal image D includes the letters "123" formed using black toner and a circle formed red using equal amounts of yellow and magenta toner, the interior of which is not filled. I'm out.

In FIG. 11, the patch image with cyan toner, which is not normally used for forming the image D, has the same forced discharge toner width in all the regions 1 to 8. On the other hand, the patch image with black, magenta, and yellow toner has a different forced discharge toner width for each region in order to avoid mechanical damage to the image forming unit 27.

The patch image with black toner usually has a forced discharge toner width smaller than the other regions in the regions 2 and 3 corresponding to the position of the character "123" formed on the upper part of the image D. Further, since the region 3 contains the characters in a larger proportion than the region 2 of the normal image D, the region 3 has a smaller forced discharge toner width than the region 2 of the patch image.

Similarly, patch images with magenta and yellow toner usually have a smaller forced discharge toner width in regions 3-6 corresponding to the position of the circle formed in the center of image D than the other regions. Further, since the areas 3 and 6 include the outline portion of the circle in a larger proportion than the areas 4 and 5 of the normal image D, the areas 3 and 6 are larger than the areas 4 and 5 of the patch image. It has a small forced discharge toner width.

Similar to the above embodiment, the image forming system 1 of the modification 1 does not forcibly discharge the toner when the foil pressing image is subsequently formed. Hereinafter, the process of calculating the forced discharge toner width of the first modification 1 will be described in detail with reference to FIG.

FIG. 12 is a subroutine flowchart showing another example of the procedure for calculating the forced discharge toner width in steps S105 and S112 of FIG.

First, the control unit 21 acquires, as the acquisition unit 213, the amount of toner used for forming each image for each toner color and for each predetermined region based on each image data (step S401). The predetermined region means a plurality of regions divided by a predetermined width in the main scanning direction when forming an image. As described above, the predetermined width may be one-eighth of the predetermined forced discharge toner length (for example, 330 mm), but is not limited thereto. For example, the predetermined width may be another width such as a width of 1/6 of the predetermined forced discharge toner length. Further, in the first modification, the area of the formed image can be acquired as the amount of toner used, as in the above embodiment.

Subsequently, the control unit 21, as the acquisition unit 213, acquires the coverage of the image of each region for each toner color based on the amount of toner used in each region (step S402). Then, the control unit 21 sets the set value N to 1 (step S403). The set value N is a value indicating each divided area.

Subsequently, the control unit 21 determines, as the determination unit 214, whether or not the coverage of the region N is less than a predetermined coverage (second threshold value) for each toner color (step S404). The predetermined coverage may be, for example, 5% or may be set by the user.

When the coverage of the area N is less than the predetermined coverage (step S404: YES), the control unit 21 determines that the toner of the area N needs to be forcibly discharged as the determination unit 214 (step S405). Then, the control unit 21, as the calculation unit 215, calculates the forced discharge toner width for each color of the toner in the area N based on the coverage of the area N (step S406).

For example, when the predetermined coverage is 5% and the reference value of the paper length in the sub-scanning direction is 210 mm, the control unit 21 calculates the forced discharge toner width based on the following formula. Since the following equation is substantially the same as the equation described in the above embodiment, detailed description thereof will be omitted.

On the other hand, when the coverage of the area N is not less than the predetermined coverage (step S404: NO), that is, when it is equal to or more than the predetermined coverage, the control unit 21 proceeds to the process of step S407. Then, the control unit 21 determines that it is not necessary to forcibly discharge the toner in the region N as the determination unit 214 (step S407). Then, the control unit 21 calculates the forced discharge toner width of the region N as 0 as the calculation unit 215 (step S408).

Subsequently, the control unit 21 increases the set value N to N + 1 and resets it (step S409). Then, the control unit 21 determines whether or not the set value N is equal to or less than the number of divided regions (step S410).

When the set value N is equal to or less than the number of regions (step S410: YES), the control unit 21 returns to the process of step S404. Then, the control unit 21 repeats the processes of steps S404 to S410 until the set value N is not less than or equal to the number of divided regions (step S410: NO), that is, exceeds the number of divided regions. As a result, the control unit 21 can determine whether or not it is necessary to forcibly discharge the toner in the entire divided region.

When the set value N is not equal to or less than the number of regions (step S410: NO), the control unit 21 returns to the process of FIG. After returning to the process of FIG. 6, the control unit 21 forcibly discharges the toner corresponding to the forced discharge toner width of each region to the image forming unit 27 in step S106, or the forced discharge toner width of each region in step S114. The amount of forced discharge toner in each area is calculated from.

As described above, according to the image forming system 1 of the modification 1, it is determined for each region whether or not it is necessary to forcibly discharge the toner based on the amount of toner used in each region. Therefore, the image forming system 1 can effectively suppress the mechanical damage of the image forming unit 27.

The image forming system 1 may be executed by combining the processes of calculating the forced discharge toner width of FIGS. 7 and 12. The image forming system 1 may select, for example, a process of calculating the forced discharge toner width to be executed for each toner color. The image forming system 1 applies, for example, the process of FIG. 7 to calculate the forced discharge toner widths of yellow and magenta, and applies the process of FIG. 12 to calculate the forced discharge toner widths of cyan and black. May be good. As a result, the image forming system 1 can prioritize the stability of the image quality and the avoidance of mechanical damage for each toner color.

Further, the image forming system 1 may execute the process of calculating the forced discharge toner width of both FIGS. 7 and 12, and adopt the forced discharge toner width calculated larger for each region. As a result, the image forming system 1 can avoid mechanical damage while stabilizing the image quality.

(Modification 2)
In the above embodiment, it has been described that the image forming system 1 selects the foil stamping color by comparing the amount of the foil stamping toner with the amount of the forced discharge toner for each color of the toner. In the second modification, the image forming system 1 describes selecting the foil stamping color by a different method.

FIG. 13 is a subroutine flowchart showing another example of the procedure for forming the foil stamping image in step S111 of FIG. Since the processes of steps S501 to S505 of FIG. 13 are the same as the processes of steps S301 to S305 of FIG. 8, the description thereof will be omitted.

In step S506, the control unit 21 selects, as the selection unit 216, the color of all the toners having the cumulative forced discharge toner amount as the foil stamping color (step S506).

Subsequently, the control unit 21, as the acquisition unit 213, determines the amount of toner to be used for forming all the foil stamping images based on all the foil stamping image data included in the print job (hereinafter referred to as "total foil stamping toner amount"). ") Is acquired (step S507). The control unit 21 may execute the processes of steps S505 and S506 in the order of the processes of step S507.

Subsequently, the control unit 21, as the calculation unit 215, divides the total amount of foil stamping toner acquired in step S507 by the number of foil stamping colors selected in step S506 to calculate the amount of foil stamping toner for each foil stamping color. (Step S508).

Subsequently, the control unit 21 causes the image forming unit 27 to form a foil stamping image using the foil stamping color toner selected in steps S502, S504 or S506 as the image control unit 212 (step S509).

When the foil stamping color is selected in step S506, the control unit 21 applies the toners of all colors having the cumulative forced discharge toner amount to the image forming unit 27 by the amount of foil stamping toner of each foil stamping color calculated in step S508. Use evenly to form a foil stamping image. The control unit 21 may cause the image forming unit 27 to use toner in the order of, for example, yellow, magenta, cyan, and black to form an image for foil pressing. The control unit 21 causes the image forming unit 27 to evenly divide one foil pressing image in the sub-scanning direction by the number of foil pressing colors, and use different foil pressing colors for each divided region to form the foil pressing image. You may. Alternatively, the control unit 21 causes the image forming unit 27 to continuously use only the foil stamping color by the amount of the foil stamping toner of each foil stamping color until a certain foil stamping color is used by the amount of the foil stamping toner of each foil stamping color. After being used, the foil stamping color to be used may be switched.

Since the process of step S510 of FIG. 13 is the same as the process of step S317 of FIG. 8, the description thereof will be omitted.

Hereinafter, the above processing will be further described with reference to FIG.

FIG. 14 is a diagram for explaining yet another example of the relationship between the amount of foil pressed toner and the amount of cumulative forced discharge toner.

FIG. 14A shows the cumulative forced discharge toner amount and the foil stamping toner amount before the foil stamping image is formed. Here, it is assumed that the cumulative forced discharge toner amount of yellow is 80 mm ² , the cumulative forced discharge toner amount of magenta is 50 mm ² , the cumulative forced discharge toner amount of cyan is 30 mm ² , and the cumulative forced discharge toner amount of black is 0 mm ^2. To do. Then, it is assumed that the total amount of foil stamping toner to be used for forming all the foil stamping images is 120 mm ^2. In this case, the control unit 21 selects yellow, magenta, and cyan whose cumulative forced discharge toner amount exceeds 0 as the foil stamping color. Further, the control unit 21 divides the total amount of foil stamping toner by 3 which is the number of foil stamping colors, and calculates the ^{amount of foil stamping toner of each foil stamping color as 40 mm 2.}

FIG. 14B shows the remaining amount of the cumulative forced discharge toner amount after the foil pressing image is formed on the premise of the condition of the toner amount of FIG. 14A. Since the yellow, magenta, and cyan toners ^{were used in an amount of 40 mm 2 for} each foil pressing color, the cumulative forced discharge toner amount for yellow is 40 mm ² , and the cumulative forced discharge toner amount for magenta is 10 mm ² . Further, the cyan toner is used in excess of the cumulative forced discharge toner amount, and the cumulative forced discharge toner amount becomes 0 mm ² .

As described above, according to the image forming system 1 of the modification 2, when it is determined that it is necessary to forcibly discharge the toners of a plurality of different colors, the toners of a plurality of different colors are evenly used and the foil is pressed. Form an image for use. Therefore, the image forming system 1 can form an image for foil pressing by evenly using toner having a cumulative forced discharge toner amount of more than 0.

When the process of forming the image for foil pressing of the modification 2 is executed, the control unit 21 selects the foil pressing color based on the cumulative forced discharge toner amount at the time confirmed in step S505, and of each foil pressing color. Calculate the amount of foil stamping toner. Therefore, once the foil stamping color is selected in step S506, the control unit 21 does not have to repeat the processes such as steps S113 and S114 in FIG. 6 and steps S501 to S508 in FIG. As a result, the control unit 21 can simplify the process.

Further, in the above embodiment, the image forming apparatus 20 and the like in the image forming system 1 have been described as one apparatus. However, the present invention is not limited to this. For example, with respect to the image forming apparatus 20, an information processing apparatus that executes an image forming color selection process and the like and an apparatus that executes an image forming process may be separately configured. In this case, the information processing device and the device that executes the image forming process are connected via a bus.

The means and methods for performing various processes in the image forming system 1 according to the above-described embodiment can be realized by either a dedicated hardware circuit or a programmed computer. The above program may be provided by a computer-readable recording medium such as a USB memory, a flexible disk and a CD-ROM (Compact Disc Read Only Memory), or may be provided online via a network such as the Internet. May be good. In this case, the program recorded on the computer-readable recording medium is usually transferred and stored in a storage unit such as a hard disk. Further, the above program may be provided as a single application software, or may be incorporated into the software of each device as a function of the image forming system 1.

1 Image formation system,
10 Paper feed device,
11, 21, 31, 41 Control unit,
12, 22, 32, 42 storage units,
13, 23, 33, 43 communication unit,
14 Paper feed section,
20 Image forming device,
211 Job reception department,
212 Image control unit,
213 Acquisition Department,
214 Judgment Department,
215 calculation unit,
216 selection section,
24 Image processing unit,
25 Operation panel,
26 Paper feed section,
27 Image forming part,
28 Fixing part,
30 Foil stamping device,
34 Foil transfer part,
40 Aftertreatment device,
44 Post-processing unit,
45 Paper ejection section.

Claims (10)

An image forming system capable of performing foil stamping printing by transferring foil to a foil stamping image formed by toner.
An image forming unit that sequentially forms an image using the toner, and an image forming unit.
A determination unit for determining whether or not the toner needs to be forcibly discharged to the image forming unit, and a determination unit.
Have,
The image forming unit can form a normal image and the foil pressing image, and even if the determination unit determines that it is necessary to forcibly discharge the toner together with the normal image, it is subsequently formed. An image forming system that does not forcibly discharge the toner when there is an image for foil pressing. The image forming part is
The image is formed based on the image data included in the print job, and the image is formed.
Even if the determination unit determines that it is necessary to forcibly discharge the toner, the foil pressing image used for forming the foil pressing image is added to the image data subsequently processed in the printing job. The image forming system according to claim 1, wherein the toner is not forcibly discharged when data is included. Further having an acquisition unit for acquiring the amount of toner used, which is the amount of the toner used for forming the image based on the image data.
The image forming system according to claim 2, wherein the determination unit determines that it is necessary to forcibly discharge the toner when the amount of toner used acquired by the acquisition unit is less than a predetermined first threshold value. .. An acquisition unit that acquires the amount of toner used, which is the amount of toner used to form the image based on the image data, for each of a plurality of regions divided by a predetermined width in the main scanning direction when forming the image. Have more
The determination unit needs to forcibly discharge the toner when at least one of the toner amounts used in each region acquired by the acquisition unit is less than a predetermined second threshold value. The image forming system according to claim 2, which is determined to be present. When the determination unit determines that it is necessary to forcibly discharge the toner, a calculation unit for calculating the amount of forced discharge toner, which is the amount of the toner that needs to be forcibly discharged to the image forming unit, is used. Have more
When the image data to be subsequently processed in the print job does not include the image data for foil pressing, the image forming unit needs to forcibly discharge the toner by the determination unit. The image forming system according to claim 3 or 4, wherein when it is determined, the toner of the forced discharge toner amount calculated by the calculation unit is forcibly discharged. The calculation unit
Each time the forced discharge toner amount is calculated, the cumulative value of the forced discharge toner amount is further calculated.
Each time the image forming portion forms the foil pressing image, the amount of toner used to form the foil pressing image is subtracted from the cumulative value.
In the image forming unit, even when the image data for foil pressing is included in the image data subsequently processed in the print job, the cumulative value calculated by the calculation unit is a predetermined third at a predetermined timing. The image forming system according to claim 5, wherein the toner is forcibly discharged when the value is equal to or higher than the threshold value. Further, it has a selection unit for selecting the color of the toner used for forming the foil pressing image from the toners having a plurality of different colors.
The determination unit determines whether or not it is necessary to forcibly discharge the toner for each color of the toner.
The acquisition unit acquires the amount of foil-pressing toner, which is the amount of the toner to be used for forming the foil-pressing image based on the foil-pressing image data.
When the determination unit determines that it is necessary to forcibly discharge a plurality of different colors of the toner, the calculation unit calculates the amount of the forced discharge toner for each color of the toner.
The selection unit is used for forming the foil pressing image by comparing the amount of the foil pressing toner acquired by the acquisition unit with the forced discharge toner amount for each color of the toner calculated by the calculation unit. Select the color of at least one of the toners
The image forming system according to claim 5 or 6, wherein the image forming section uses the toner of the color selected by the selecting section to form the foil pressing image. The selection unit selects the color of the toner having a larger amount of the forced discharge toner for each color of the toner calculated by the calculation unit as the color of the toner to be preferentially used for forming the foil pressing image. The image forming system according to claim 7. The determination unit determines whether or not it is necessary to forcibly discharge each of the plurality of different toner colors.
When the image forming unit determines that it is necessary for the determination unit to forcibly discharge the toners of a plurality of different colors, the image forming unit uses the toners of the plurality of different colors evenly for the foil pressing. The image forming system according to any one of claims 1 to 6, wherein an image is formed. It has a foil transfer unit that transfers foil to a foil pressing image formed by toner, and an image forming unit that can form a normal image and the foil pressing image using the toner and sequentially forms images. A method performed in an image forming system capable of performing foil stamping,
The step (a) of determining whether or not it is necessary to forcibly discharge the toner to the image forming portion, and
Even if it is determined in step (a) that it is necessary to forcibly discharge the toner together with the normal image, if there is a foil pressing image formed thereafter, the toner is forcibly discharged. Step (b) that does not allow
Image forming method including.

Images