Image forming apparatus and program

Abstract

To prevent the occurrence of a situation where execution of print instructions is interrupted due to the amount of recovered developer, compared with a case where print instructions are executed in the order of reception irrespective of the amount of recovered developer to be recovered along with execution of the received print instructions and the state of a storage container storing the recovered developer.SOLUTION: An image forming apparatus comprises a processor, and when a result of detection of the state of a storage container storing recovered developer to be recovered along with formation of an image with developer is determined in advance, the processor predicts the amount of recovered developer to be recovered along with execution of received print instructions (step 504), receives a first print instruction and subsequently receives a second print instruction as the print instructions, and when the predicted amount of recovered developer in the second print instruction is smaller than that in the first print instruction, changes the printing order so as to print the second print instruction earlier than the first print instruction (step 506).SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus and a program. [Background technology]

[0002] For example, Patent Document 1 discloses a configuration including an image output unit that outputs a toner image on a recording material, a collection unit that collects toner that is no longer needed in the image output unit as waste toner, a removable container that stores the collected waste toner, a transfer pipe that is arranged to connect the collection unit and the container and transfers the collected waste toner to the container, an opening / closing member that opens and closes the discharge outlet of the transfer pipe in accordance with the installation and removal of the container, a transport member that rotates inside the transfer pipe and transports the waste toner toward the discharge outlet, and a control means that, when the container is removed while the image output unit and transport member are operating, changes the rotational speed of the transport member to a speed slower than the rotational speed before the container was removed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-95819 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, consider a mode in which, when the amount of recovered developer recovered in association with the execution of received print instructions varies for each print instruction, the print instructions are executed in the order of reception regardless of the state of the storage container that contains the recovered recovered developer. If one print instruction received first among the sequentially received print instructions requires a larger amount of recovered developer than another print instruction received next, there is a risk that the execution of the one print instruction and the other print instructions will be canceled due to the amount of recovered developer for the one print instruction. The object of the present invention is to prevent the execution of a print instruction from being canceled due to the amount of recovered developer, compared to when print instructions are executed in the order of receipt regardless of the amount of recovered developer recovered in conjunction with the execution of the received print instruction and the state of the storage container that contains the recovered developer. [Means for solving the problem]

[0005] The invention described in claim 1 is an image forming device that includes a processor, which, when the result of detecting the state of a storage container that contains recovered developer recovered in the course of forming an image with developer is predetermined, predicts the amount of recovered developer that will be recovered in the course of carrying out a received print instruction, receives a first print instruction as the print instruction, and then receives a second print instruction, and, if the predicted amount of recovered developer for the second print instruction is less than that for the first print instruction, changes the print order so that the second print instruction is printed before the first print instruction. The invention described in claim 2 is the image forming apparatus described in claim 1, characterized in that the predetermined case is that the amount of recovered developer in the storage container when the storage container is installed is a predetermined amount. The invention described in claim 3 is the image forming apparatus described in claim 2, characterized in that when the predetermined amount is less than the upper limit of the amount of recovered developer that can be stored in the storage container, the motor that recovers the recovered developer from the image forming unit rotates at a higher speed than when the amount of recovered developer in the storage container has not reached the small amount. The invention described in claim 4 is the image forming apparatus described in claim 2, characterized in that when the predetermined amount is the upper limit of the amount of recovered developer that can be stored in the storage container, the motor that recovers the recovered developer from the image forming unit rotates at a slower speed than when the amount of recovered developer in the storage container is not at the upper limit. The invention described in claim 5 is the image forming apparatus described in claim 1, characterized in that the predetermined case is when it is detected that the storage container has been removed. The invention described in claim 6 is the image forming apparatus described in claim 5, characterized in that the motor that recovers recovered developer from the image forming unit rotates at a slower speed than when the storage container is attached. The invention described in claim 7 is the image forming apparatus described in claim 6, characterized in that when the result of the status detection changes from detecting that the storage container is removed to detecting that the storage container is installed, the rotation of the motor is changed to a high speed. The invention described in claim 8 is an image forming apparatus described in claim 1, characterized in that when the image formed by the developer by the printing instruction satisfies predetermined conditions and developer is supplied to a predetermined area without the printing instruction, the amount of recovered developer is predicted based on the amount of developer that is not transferred when the image formed by the developer is transferred to a recording medium and the amount of developer supplied to the predetermined area. The invention described in claim 9 is the image forming apparatus described in claim 8, characterized in that the amount of developer supplied to the predetermined area is increased for at least one of the first print instruction and the second print instruction. The invention described in claim 10 is the image forming apparatus described in claim 1, characterized in that the amount of recovered developer in the path that transports the recovered developer to a storage container is predicted, and if the predicted result is an upper limit, the first print instruction and the second print instruction are not executed. An eleventh aspect of the present invention is the image forming apparatus according to the first aspect, characterized in that it is possible to switch between a case where the printing order is changed and a case where the printing order is not changed. The invention described in claim 12 is a program that enables an information processing device to implement the following functions: a function to predict the amount of recovered developer to be recovered in accordance with the implementation of a received print instruction when the result of detecting the state of a storage container that contains recovered developer recovered in accordance with the formation of an image with developer is predetermined; and a function to accept a second print instruction after accepting a first print instruction as the print instruction, and if the predicted amount of recovered developer for the second print instruction is less than that for the first print instruction, change the print order so that the second print instruction is printed before the first print instruction. [Effects of the Invention]

[0006] According to the invention of claim 1, it is possible to prevent the execution of a print instruction from being canceled due to the amount of recovered developer, compared to when the print instructions are executed in the order of receipt, regardless of the amount of recovered developer recovered in conjunction with the execution of the received print instruction and the state of the storage container that contains the recovered developer. According to the invention of claim 2, when it is predetermined, it is possible to prevent the occurrence of a situation in which the execution of a print instruction is interrupted due to the amount of recovered developer, compared to a case in which the configuration in which the amount of recovered developer in the storage container when the storage container is attached is not provided. According to the invention of claim 3, when the predetermined amount is less than the upper limit of the amount of recovered developer that can be stored in the storage container, the motor that recovers the recovered developer from the image forming unit can be prevented from canceling the execution of the print instruction even if the storage container is subsequently removed, compared to when the motor is not configured to rotate at a higher speed than when the amount of recovered developer in the storage container has not reached a low level. According to the invention of claim 4, when the predetermined amount is the upper limit of the amount of recovered developer that can be stored in the storage container, the number of print instructions that can be executed can be increased compared to when the motor that recovers the recovered developer from the image forming unit does not have a configuration in which it rotates at a slower speed than when the recovered developer in the storage container is not at the upper limit. According to the invention of claim 5, when it is predetermined, it is possible to prevent the execution of a print instruction from being stopped due to the amount of recovered developer after the storage container is removed, compared to when the configuration is not provided in which the removal of the storage container is detected. According to the invention of claim 6, the number of print instructions that can be executed can be increased compared to when the motor that recovers recovered developer from the image forming unit is not configured to rotate at a slower speed than when a storage container is attached. According to the invention of claim 7, when the result of the status detection changes from detecting that the storage container is removed to detecting that the storage container is attached, the motor rotation speed is changed to high speed, and the recovered developer in the transport path to the storage container can be transported to the storage container more quickly than in a case where the configuration is not provided. According to the invention of claim 8, when an image formed by developer according to a printing instruction satisfies predetermined conditions and developer is supplied to a predetermined area without a printing instruction, the accuracy of the prediction of the amount of recovered developer can be improved compared to when the configuration is not provided in which the prediction is performed based on the amount of developer that is not transferred when an image formed by developer is transferred to a recording medium and the amount of developer that is supplied to the predetermined area. According to the invention of claim 9, the amount of recovered developer can be reduced compared to a case where a configuration for increasing the amount of developer supplied to a predetermined area is not provided for at least one of the first print instruction and the second print instruction. According to the invention of claim 10, the amount of recovered developer in the path that transports the recovered developer to the storage container is predicted, and if the predicted result is at the upper limit, it is possible to avoid a situation in which a print instruction being executed is interrupted midway, compared to a case in which the configuration is not provided in which the first print instruction and the second print instruction are not executed. According to the invention of claim 11, it is possible to provide the user with more options than in a case where there is no configuration that allows switching between changing the printing order and not changing the printing order. According to the invention of claim 12, it is possible to prevent the execution of a print instruction from being canceled due to the amount of recovered developer, compared to when the print instructions are executed in the order of receipt, regardless of the amount of recovered developer recovered in conjunction with the execution of the received print instruction and the state of the storage container that contains the recovered developer. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an image forming apparatus. [Figure 2] FIG. 1 is a diagram illustrating a waste toner recovery system in an image forming apparatus. [Figure 3] FIG. 10 is a cross-sectional view showing the configuration of a fourth transfer device. [Figure 4] 3A and 3B are diagrams illustrating the configuration of a collection container, where FIG. 3A shows an example according to FIG. 2, and FIG. 3B shows another example. [Figure 5] FIG. 2 is a diagram illustrating an example of the hardware configuration of a control unit of the image forming apparatus. [Figure 6] FIG. 2 is a block diagram illustrating the functional configuration of a control unit. [Figure 7] 10 is a flowchart illustrating a waste toner collection process according to the state of the collection container. [Figure 8] 10 is a flowchart illustrating clogging prevention control. [Figure 9] 10 is a flowchart illustrating a process for determining whether to interrupt a print instruction based on the amount of waste toner generated. [Figure 10] 10 is a flowchart illustrating a process for calculating the amount of waste toner generated. [Figure 11] 10 is a flowchart illustrating a print instruction switching process. [Figure 12] 10A and 10B are diagrams illustrating a process for calculating the amount of discharged and discarded toner, where FIG. 10A is a flowchart and FIG. 10B is a table used in the flowchart of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. <Image forming apparatus 1> FIG. 1 is a diagram illustrating an image forming apparatus 1. As shown in FIG. The image forming apparatus 1 according to this embodiment includes a paper feed unit 1A, a printing unit 1B, and a paper discharge unit 1C. The paper feed unit 1A includes a first paper storage section 11 to a fourth paper storage section 14 that store paper P as an example of a recording medium. In addition, the paper feed unit 1A is provided with feed rolls 15 to 18 that correspond to each of the first paper storage section 11 to fourth paper storage section 14 and feed the paper P stored in each paper storage section to a transport path connected to the printing unit 1B. The image forming apparatus 1 is an example of an information processing apparatus.

[0009] The printing unit 1B includes an image forming section 20 that forms an image on a sheet P. The printing unit 1B also includes a control section 21 that controls each section of the image forming apparatus 1. The printing unit 1B also includes an image processing section 22. The image processing section 22 performs image processing on image data transmitted from the image reading device 4 and the personal computer (PC) 5. The printing unit 1B is also provided with a UI (User Interface) 23, which is configured with a touch panel or the like and notifies the user of information and receives information input from the user.

[0010] The image forming section 20, which is an example of an image forming means, is provided with six image forming units 30T, 30P, 30Y, 30M, 30C, and 30K (hereinafter, sometimes simply referred to as "image forming units 30") arranged in parallel at regular intervals. Each image forming unit 30 includes a photosensitive drum 31 on which an electrostatic latent image is formed while rotating in the direction of arrow A, a charging roll 32 that charges the surface of the photosensitive drum 31, a developing device 33 that develops the electrostatic latent image formed on the photosensitive drum 31, and a drum cleaner 34 that removes toner and the like from the surface of the photosensitive drum 31.

[0011] The image forming section 20 is also provided with a laser exposure device 26 that exposes the photosensitive drum 31 of each image forming unit 30 to laser light. The exposure of the photosensitive drum 31 by the laser exposure device 26 is not limited to using laser light. For example, a light source such as an LED (Light Emitting Diode) may be provided for each image forming unit 30, and the photosensitive drum 31 may be exposed using light emitted from the light source.

[0012] Each image forming unit 30 is configured similarly except for the toner stored in the developing device 33. Image forming units 30Y, 30M, 30C, and 30K form toner images of yellow (Y), magenta (M), cyan (C), and black (K), respectively. Furthermore, the image forming units 30T and 30P form toner images using toner corresponding to the corporate color, foam toner for Braille, fluorescent color toner, toner for improving gloss, etc. In other words, the image forming units 30T and 30P form toner images using toner of a particular color.

[0013] Here, image forming units 30T and 30P are an example of one image forming unit that forms a developer image of one color on the surface of one image carrier, and image forming units 30Y, 30M, 30C, and 30K are examples of other image forming units located downstream of the one image forming unit that form developer images of other colors on the surface of other image carriers. That is, photoconductor drums 31 of image forming units 30T and 30P are an example of one image carrier, and the developer of one color is the developer of image forming units 30T and 30P. Also, photoconductor drums 31 of image forming units 30Y, 30M, 30C, and 30K are an example of other image carriers, and the developers of other colors are the developers of image forming units 30Y, 30M, 30C, and 30K.

[0014] The image forming section 20 is also provided with an intermediate transfer belt 41 onto which the toner images of each color formed by the photosensitive drums 31 of the image forming units 30 are transferred. The image forming section 20 is also provided with primary transfer rolls 42 that transfer the respective color toner images of the image forming units 30 onto the intermediate transfer belt 41 at the primary transfer section T1. The image forming unit 20 is also provided with a secondary transfer roll 40 that transfers the toner images transferred onto the intermediate transfer belt 41 onto the paper P at a secondary transfer unit T2. Furthermore, the image forming unit 20 is provided with a belt cleaner 45 that removes toner and the like from the surface of the intermediate transfer belt 41, and a fixing device 80 that fixes the secondarily transferred image onto the paper P.

[0015] The image forming unit 20 performs an image forming operation based on a control signal from the control unit 21 . Specifically, in the image forming unit 20, first, image processing is performed by the image processing unit 22 on the image data input from the image reading device 4 or the PC 5, and the image data after image processing is supplied to the laser exposure device 26. For example, in the magenta (M) image forming unit 30M, the surface of the photosensitive drum 31 is charged by the charging roll 32, and then the laser exposure device 26 irradiates the photosensitive drum 31 with laser light modulated by image data obtained from the image processing unit 22.

[0016] As a result, an electrostatic latent image is formed on the photosensitive drum 31 . The formed electrostatic latent image is developed by the developing unit 33, and a magenta toner image is formed on the photosensitive drum 31. Similarly, yellow, cyan and black toner images are formed in the image forming units 30Y, 30C and 30K, and special color toner images are formed in the image forming units 30T and 30P.

[0017] The color toner images formed by each image forming unit 30 are sequentially electrostatically transferred onto an intermediate transfer belt 41 rotating in the direction of arrow C in Figure 1 by a primary transfer roll 42, forming superimposed toner images on the intermediate transfer belt 41. The superimposed toner image formed on the intermediate transfer belt 41 is transported to a secondary transfer portion T2 constituted by a secondary transfer roll 40 and a backup roll 49 as the intermediate transfer belt 41 moves.

[0018] On the other hand, the paper sheet P is taken out from the first paper storage unit 11 by, for example, the delivery roll 15, and then transported to the position of the registration roll 74 via the transport path. When the superimposed toner image is transported to the secondary transfer portion T2, the paper P is supplied from the registration roll 74 to the secondary transfer portion T2 in accordance with this timing. Then, at the secondary transfer portion T2, the superimposed toner images are electrostatically transferred onto the paper P in a lump due to the action of a transfer electric field formed between the secondary transfer roll 40 and the backup roll 49.

[0019] Thereafter, the paper P onto which the superimposed toner images have been electrostatically transferred is transported to the fixing device 80. In the fixing device 80, the paper P on which the unfixed toner image has been formed is pressurized and heated, and the toner image is fixed to the paper P. Then, the paper P on which the fixing process has been performed passes through a curl correction section 81 provided in the paper discharge unit 1C, and is then conveyed to a paper stacking section (not shown).

[0020] <Waste Toner Collection System 100> 1, the image forming apparatus 1 according to the present embodiment is equipped with a waste toner recovery system 100 that collects unnecessary toner from the drum cleaner 34 and the belt cleaner 45 as waste toner and then collects it in a collection container 200 (see FIG. 2 or FIG. 4). The waste toner here refers to total waste toner 90 (see FIG. 2 or FIG. 4), which will be described later. The collection container 200 is an example of a storage container.

[0021] FIG. 2 is a diagram illustrating a waste toner recovery system 100 in the image forming apparatus 1. As shown in FIG. As shown in FIG. 2, the waste toner collection system 100 is composed of a collection container 200 that ultimately collects all the waste toner 91, 92 discharged from each drum cleaner 34 and belt cleaner 45 in the image forming unit 20 (see FIG. 1), and a transport device 102 that collects the waste toner 91, 92 discharged from each drum cleaner 34 and belt cleaner 45 and transports it to the collection container 200.

[0022] The waste toner 91 is toner and the like that is discharged after unwanted matter such as toner remaining on the peripheral surface of each photosensitive drum 31 in each image forming unit 30 (see Figure 1) (Y, M, C, K, T, P) of the image forming section 20 after the primary transfer is removed and collected by the drum cleaner 34. That is, the waste toner 91 is untransferred toner that has not been primarily transferred at the primary transfer portion T1.

[0023] The waste toner 92 is toner and the like that is discharged after unwanted matter such as toner remaining on the outer surface of the intermediate transfer belt 41 (see Figure 1) in the intermediate transfer device of the image forming unit 20 is removed and collected by the belt cleaner 45. More specifically, the waste toner 92 includes waste toner 92a, which is toner that has not been secondarily transferred at the secondary transfer portion T2, and waste toner 92b, which is toner that has been discharged.

[0024] The reason for toner discharge is as follows: When intermediate transfer belt 41 (see FIG. 1) runs continuously while paper P (see FIG. 1) is narrow, toner is not supplied to the area outside the paper width, which is the area outside the paper width, and this causes the belt cleaner 45 (see FIG. 1) that comes into contact with intermediate transfer belt 41 in the area outside the paper to curl up. To prevent this, it is necessary to periodically supply toner to the area outside the paper as a lubricant, and toner discharge is performed. The amount of toner discharged varies depending on the image density of the image specified for printing: the lower the image density, the greater the amount of toner discharged, and the higher the image density, the less the amount of toner discharged. The toner discharge is an example of a case where the developer is supplied to a predetermined area without a print instruction when the image formed by the developer in response to a print instruction satisfies predetermined conditions. The area outside the paper is an example of a predetermined area.

[0025] The waste toner 91 and the waste toner 92 may be collectively referred to as "total waste toner 90 (see FIG. 2)." In other words, the sum of the amount of waste toner 91 and the amount of waste toner 92 is the amount of total waste toner 90. The amount of total waste toner 90 is an example of the amount of recovered developer that is collected. The waste toner 91 and the waste toner 92a may be collectively referred to as “untransferred waste toner.” That is, the sum of the amount of waste toner 91 and the amount of waste toner 92a is the amount of untransferred waste toner. The waste toner 92b may also be referred to as "discharged waste toner 92b."

[0026] The transfer device 102 includes a first transfer device 110 that transfers waste toner 91 discharged from the drum cleaners 34 of each image forming unit 30 as a single unit, a second transfer device 120 that transports waste toner 92 discharged from the belt cleaner 45, a third transfer device 130 that transfers waste toner 91, 92 transferred by the first transfer device 110 and the second transfer device 120 as a single unit, and a fourth transfer device 140 that finally transfers waste toner 91, 92 transferred by the third transfer device 130 to the collection container 200.

[0027] Of these, the first transport device 110 is composed of a first transport pipe 112 that is positioned below each image forming unit 30 in a substantially horizontal state, i.e., along the direction indicated by the coordinate axis X (see Figure 3), a transport member 113 that rotates in the internal space of the first transport pipe 112, which has a circular cross section, to transport the waste toner 91 downstream in the transport direction, and a first drive device 114 that transmits rotational power to the transport member 113. The transfer direction is the direction indicated by the arrow drawn near the first transfer pipe 112 in Fig. 2. The transfer direction in each of the subsequent transfer pipes is the same.

[0028] The first transfer pipe 112 of the first transfer device 110 is connected to a connecting transfer device 115 (SY, SM, SC, SK, SA, SB) that connects the waste toner discharge outlets of the drum cleaners 34 in each image forming unit 30 and transfers the waste toner 91. Each of these connecting and transporting devices 115 is composed of a tubular member 116 that is arranged in a state that is roughly aligned in the vertical direction (vertical direction of coordinate axis Y (see Figure 3)) so as to connect the discharge outlets of the drum cleaners 34 in each image forming unit 30, a breaking-up member 117 that moves back and forth in an up-and-down direction within the internal space of the tubular member 116 to break down waste toner and the like that has adhered to the inner wall, and a drive unit 118 that transmits power to move the breaking-up member 117 back and forth. The breaking member 117 may be, for example, a coil spring having no rotation axis and made of a wire wound in a spiral shape.

[0029] The second transfer device 120 is composed of a second transfer pipe 122 that is positioned in a nearly horizontal state in a rear portion of the main body of the printing unit 1B, below the belt cleaner 45, a conveying member 123 (not shown) that rotates in the internal space of the second transfer pipe 122, which has a circular cross section, to transfer the waste toner 92 downstream in the conveying direction, and a second drive device 124 that transmits rotational power to the conveying member 123. The downstream side in the transfer direction of the second transfer device 120 is joined to the downstream end of the first transfer pipe 112 of the first transfer device 110, and their internal spaces are connected to each other.

[0030] A connecting / transporting device 125 is connected to the second transfer pipe 122 of the second transfer device 120, and connects the second transfer pipe 122 to the waste toner discharge port of the belt cleaner 45 to transfer the waste toner 92. The connecting transport device 125 is composed of at least a tubular member that is arranged substantially vertically so as to connect the discharge port of the belt cleaner 45 and the second transport pipe 122. Incidentally, when the third transport device 130 is arranged on the opposite side of the belt cleaner 45 from the image forming unit 30, the second transport device 120 does not need to be installed, and it is sufficient to configure the connecting transport device 125 to be connected to a part of the first transport pipe 112 of the first transport device 110, for example.

[0031] The third transfer device 130 is composed of a tubular member 132 arranged in a state that is aligned approximately vertically from the joint between the first transfer pipe 112 of the first transfer device 110 and the second transfer pipe 122 of the second transfer device 120 toward the fourth transfer device 140 located below in the direction of gravity (a direction approximately along the coordinate axis Y), a breaking member 133 such as a coil spring that moves back and forth in the internal space of the tubular member 132 to break down the waste toner 91, 92 adhering to the inner wall, and a third drive device 134 that transmits power to move the breaking member 133 back and forth.

[0032] The fourth transfer device 140 is composed of a fourth transfer pipe 142 that connects at least the lower part of the tubular member 132 of the third transfer device 130 to the receiving port 210 of the collection container 200 and is arranged so that the entire pipe is approximately horizontal, a transport member 143 that rotates in the internal space of the fourth transfer pipe 142, which has a circular cross section, and transports the waste toner 91, 92 downstream in the transport direction, i.e., toward the discharge port described below, and a fourth drive unit 144 that transmits rotational power to the transport member 143.

[0033] In this transfer device 102, for example, cylindrical pipes are used as the first transfer pipe 112, the second transfer pipe 122, and the fourth transfer pipe 142. For example, a tubular member 132 of the third transfer device 130 is used, which has a circular cross-sectional shape whose diameter gradually decreases toward the bottom of the internal space.

[0034] Of these, the first transfer pipe 112 has a plurality of connection ports or receiving ports at required intervals on its upper surface where it connects to the tubular members 116 of each connecting transfer device 115, for receiving waste toner discharged from the drum cleaners 34 of each image forming unit 30 through the tubular members 116. The second transfer pipe 122 has a connection port or a receiving port at the top where it connects to the tubular member of the connecting and transferring device 125, for receiving waste toner discharged from the belt cleaner 45 through the tubular member.

[0035] FIG. 3 is a cross-sectional view showing the configuration of the fourth transfer device 140. As shown in FIG. 3, the fourth transfer pipe 142 has a connection port 142a or a receiving port 142a at a portion of its upper surface that connects to the tubular member 132 of the third transfer device 130, for receiving the waste toner 91, 92 transferred through the tubular member 132. Moreover, the fourth transfer pipe 142 has a discharge port 142b at a portion of its lower surface, downstream in the direction of gravity, that connects to the receiving port of the collection container 200 (see FIG. 2), for dropping the waste toner transferred through the fourth transfer pipe 142 into the collection container 200 and discharging it.

[0036] An opening / closing shutter 148 for opening and closing the discharge port 142b is provided at a portion of the fourth transfer pipe 142 where the discharge port 142b exists. It is a plate-like member having a through-hole 148a of a corresponding size and a non-through-hole portion that blocks it, and is attached to the underside of the fourth transfer pipe 142 so as to be freely displaceable. The opening / closing shutter 148 is displaced in conjunction with the attachment / detachment of the collection container 200, thereby opening and closing the discharge port 142b. The displacement in conjunction here is achieved by the receiving port 210 (see FIG. 2) of the container 200 coming into contact with or separating from a part of the opening / closing shutter 148.

[0037] In addition, the conveying members 113, 123, and 143 in the transfer device 102 are screw augers with a basic structure in which conveying blades 146 are formed spirally wound around a cylindrical rod-shaped rotating shaft 145, as shown in Figure 3 as a representative example of the conveying member 143. The rotational power from the fourth driving device 144 is transmitted to a gear 149 fixed to one end of a rotation shaft 145 .

[0038] 4A and 4B are diagrams illustrating the configuration of the collection container 200, where (a) shows an example according to FIG. 2, and (b) shows another example. 4(a) shows an example of a waste toner container 200 that has a generally rectangular parallelepiped shape. The waste toner container 200 has a receiving opening 210 for receiving waste toner 91, 92 and a handle 220 formed on the top thereof.

[0039] Furthermore, the collection container 200 is detachably attached to a container attachment portion formed at the bottom of the main body of the printing unit 1B and is of a type that can be easily replaced (a detachable container). That is, the collection container 200 can be fitted into a mounting frame 19 provided in the container attachment portion, as exemplified in FIG. 4. When the collection container 200 is fitted into the mounting frame 19, its receiving port 210 is attached to the discharge port 142b (see FIG. 3) of the fourth transfer pipe 142 of the fourth transfer device 140. On the other hand, when the collection container 200 is removed from the mounting frame 19, the receiving port 210 moves away from the discharge port 142b. This allows the collection container 200 to be replaced.

[0040] Furthermore, by performing an attachment / detachment operation on the mounting frame 19, the collection container 200 can open and close the discharge port 142b in the fourth transfer pipe 142 by the opening / closing shutter 148 for the discharge port 142b in conjunction with the attachment / detachment operation. Specifically, for example, when the collection container 200 is attached, a part of the receiving port 210 comes into contact with and presses the opening / closing shutter 148, causing the opening / closing shutter 148 to displace to a position that opens the discharge port 142b. When the collection container 200 is removed, the part of the receiving port 210 is released from contacting and pressing the opening / closing shutter 148, causing the opening / closing shutter 148 to displace to a position that closes the discharge port 142b.

[0041] The container mounting section is also provided with a fullness detection sensor 107 that detects when the total waste toner 90, i.e., the waste toners 91 and 92 contained in the collection container 200, reaches a predetermined amount, for example, an amount just short of being completely full. The fullness detection sensor 107 also detects when the container is completely full. The fullness detection sensor 107 may be, for example, a magnetic permeability sensor that measures the magnetic permeability of the magnetic carrier of the two-component developer contained in the waste toner to detect that the amount of non-magnetic toner and magnetic carrier contained therein has exceeded a predetermined amount, but is not limited to this.

[0042] In the waste toner recovery system 100, when the fullness detection sensor 107 detects that the waste toner container 200 is full, the waste toner recovery system 100 first notifies the user of the image forming apparatus 1 that the waste toner container 200 needs to be replaced, because the waste toner container 200 is not completely full at the time of the detection and still has room to accommodate a little more to be stored. For example, a warning message is displayed on the input / display device 14 or the screen of an externally connected device.

[0043] Furthermore, the container mounting portion on the mounting frame 19 side is provided with an attachment / detachment detection sensor 108 that detects when the collection container 200 is mounted and when the collection container 200 is removed. The attachment / detachment detection sensor 108 is of a type that directly detects the presence or absence of the collection container 200 when the collection container 200 is mounted or removed. Alternatively, the attachment / detachment detection sensor 108 may be of a type that indirectly detects the mounting or detachment of the collection container 200 by detecting the state or position that is displaced when the opening / closing shutter 148 is opened or closed.

[0044] The above-mentioned fullness detection sensor 107 and attachment / detachment detection sensor 108 (see FIG. 4) are connected to the control unit 21 (see FIG. 1) of the image forming apparatus 1, and the detection results thereof are transmitted. In addition, a drive control unit 62 (see FIG. 6), which will be described later, of the control unit 21 is connected to each of the drive devices 114, 118, 124, 134, 144, etc. in the transfer device 102, and transmits required control signals related to the rotational drive of each drive device.

[0045] Next, another example of the collection container 200 shown in Fig. 4(b) will be described. Note that this other example has the same configuration as the example shown in Fig. 4(a), and therefore the description thereof will be omitted. As shown in Fig. 4(b), another example of the collection container 200 differs from the example of the collection container 200 shown in Fig. 4(a) in that it includes a fourth transfer pipe 142. Therefore, the receiving port 210 is provided at the upstream end (the right end in the figure) of the fourth transfer pipe 142. In addition, the position where the opening / closing shutter 148 (see Fig. 3) is provided is the lower end position of the tubular member 132 (see Fig. 3) of the third transfer device 130.

[0046] When the collection container 200 is removed, the fourth transfer pipe 142 is separated from the fourth drive device 144 shown by the dashed line in Fig. 4(b). Therefore, when the attachment / detachment detection sensor 108 detects that the collection container 200 has been removed, it is possible to perform control to stop driving the fourth drive device 144.

[0047] <Basic Operation of Waste Toner Recovery System 100> The waste toner recovery system 100 basically operates as follows. The waste toner recovery system 100 operates at least while the image forming operation is being performed by the image forming unit 20. That is, when the image forming operation is started, the drive devices 114, 118, 124, 134, and 144 in the transfer device 102 start to rotate or move back and forth, respectively, causing the conveying members and the loosening or breaking members to begin rotating or moving back and forth.

[0048] First, in the first transfer device 110 of the transfer device 102, waste toner 91 discharged from the drum cleaners 34 of each image forming unit 30 falls through the internal space of the tubular members 116 of each connecting transfer device 115 (SY, SM, SC, SK, SA, SB), is received and collected in the first transfer pipe 112 through each connection port, and is then conveyed by the rotationally driven conveying member 113 to move in the transfer direction indicated by the arrow within the internal space of the first transfer pipe 112. Also, in the second transfer device 120 of the transfer device 102, waste toner 92 discharged from the belt cleaner 45 falls naturally through the tubular member of the connecting transfer device 125, is received in the second transfer pipe 122 through a connection port, and is then conveyed by the rotationally driven conveying member 123 to move in the transfer direction indicated by the arrow within the internal space of the second transfer pipe 122.

[0049] Next, in the third transfer device 130 of the transfer device 102, the waste toner 91, 92 that has been transferred in each transfer direction by the first transfer device 110 and the second transfer device 120 and collected at one location, i.e., the connecting portion, falls through the tubular member 132 and is received through the connection port 142a in the fourth transfer pipe 142 of the fourth transfer device 140. Here, in each of the tubular members of the first transfer device 110, the second transfer device 120, and the third transfer device 130, the falling waste toner 91, 92 is broken down by the respective breaking members 117, 133 to eliminate any agglomerated state.

[0050] Next, in the fourth transfer device 140 of the transfer device 102, the waste toner 91, 92 received in the fourth transfer pipe 142 is transported in the transfer direction indicated by the arrow by a transport member 143 that is rotationally driven in the internal space of the fourth transfer pipe 142, and is dropped when it reaches the discharge port 142b of the fourth transfer pipe 142. As a result, the waste toner 91, 92 is collected together in the storage space of the collection container 200 through the receiving port 210 of the collection container 200.

[0051] Through the above recovery operation, the waste toner 91 discharged from the drum cleaner 34 of each image forming unit 30 and the waste toner 92 discharged from the belt cleaner 45 are collected by the transport device 102 and transported to the recovery container 200, and are finally collected by being stored in the recovery container 200.

[0052] In addition, in this waste toner recovery system 100, when the amount of waste toner 91, 92 contained in collection container 200 reaches a predetermined amount, this state is detected by full detection sensor 107. When full detection sensor 107 detects that collection container 200 is full, a warning message is displayed on UI 23 (see FIG. 1) to prompt the user of image forming apparatus 1 that collection container 200 needs to be replaced. Furthermore, after this notification of replacement has been issued, the replacement work of collection container 200 is recognized as having been performed and completed when collection container attachment / detachment detection sensor 108 detects the removal and attachment of collection container 200 as a set.

[0053] <Control unit 21> 5 is a diagram showing an example of the hardware configuration of the control unit 21 of the image forming apparatus 1. The control unit 21 is realized by a computer. The control unit 21 has an arithmetic processing unit 21a that executes digital arithmetic processing according to a program, and a secondary storage unit 21g that stores information. The secondary storage unit 21g is realized by an existing information storage device such as an HDD (Hard Disk Drive), semiconductor memory, or magnetic tape.

[0054] The arithmetic processing unit 21a is provided with a CPU 21b as an example of a processor. The arithmetic processing unit 21a is also provided with a RAM 21c used as a working memory for the CPU 21b, and a ROM 21d in which programs executed by the CPU 21b are stored. The arithmetic processing unit 21a is also provided with a non-volatile memory 21e that is rewritable and can retain data even if the power supply is interrupted, and an interface unit 21f that controls each part, such as a communication unit, connected to the arithmetic processing unit 21a.

[0055] The nonvolatile memory 21e is configured, for example, with a battery-backed SRAM, a flash memory, etc. The secondary storage unit 21g stores files, etc., as well as programs executed by the arithmetic processing unit 21a. In this embodiment, the arithmetic processing unit 21a reads programs stored in the ROM 21d or the secondary storage unit 21g, thereby executing each process.

[0056] The program executed by CPU 21b may be provided to image forming apparatus 1 in a state where it is stored in a computer-readable recording medium such as a magnetic recording medium (such as a magnetic tape or a magnetic disk), an optical recording medium (such as an optical disk), a magneto-optical recording medium, or a semiconductor memory. Alternatively, the program executed by CPU 21b may be provided to image forming apparatus 1 using a communication means such as the Internet.

[0057] In this specification, the term "processor" refers to a processor in a broad sense, and includes general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.). Furthermore, the operations of the processors may not only be performed by a single processor, but may also be performed by multiple processors located at physically separate locations working together. The order of the operations of the processors is not limited to the order described in this embodiment, and may be changed.

[0058] FIG. 6 is a block diagram illustrating the functional configuration of the control unit 21. 6, the control unit 21 includes a determination unit 61, a drive control unit 62, a state detection unit 63, a prediction unit 64, and a print order change unit 65. The determination unit 61 and the like are realized by the CPU 21b (see FIG. 5).

[0059] The determination unit 61 performs various determinations in the flowcharts described below. The drive control unit 62 controls the drive of the first drive unit 114, the drive unit 118, the second drive unit 124, the third drive unit 134, and the fourth drive unit 144 (see FIG. 2). More specifically, when the fullness detection sensor 107 (see FIG. 4) detects that the toner container has been filled to a level just short of being completely full, the drive control unit 62 increases the speed of the drive units 114, 118, 124, 134, and 144 to collect the waste toner in the transfer path into the collection container 200 (see FIG. 2) to prevent clogging due to the waste toner that will be generated from now on. In other words, the drive control unit 62 rotates the drive units at high speed to empty the transfer path. When there is free space in the collection container (see FIG. 2), the rotation speed of the collection motor is set to medium speed, and there is a relationship of high speed > medium speed > low speed. Furthermore, when the fullness detection sensor 107 (see FIG. 4) detects that the collection container 200 is full, or when the attachment / detachment detection sensor 108 (see FIG. 4) detects that the collection container 200 has been removed, the drive control unit 62 slows down the speed of the drive devices 114, 118, 124, 134, and 144 to prevent the waste toner from clogging the discharge port 142b (see FIG. 3) and accumulating in the transfer path. This allows the waste toner to be collected in the transfer pipe when the collection container 200 (see FIG. 2) is full or being replaced, and allows the execution of the print command to continue. The first driving device 114, the driving device 118, the second driving device 124, the third driving device 134, and the fourth driving device 144 are examples of motors that collect the recovered developer from the image forming unit 20.

[0060] The status detection unit 63 detects the status of the collection container 200 based on detection signals from the full detection sensor 107 and the attachment / detachment detection sensor 108. The status detection unit 63 detects the amount of total waste toner 90 in the collection container 200 based on the detection signal from the full detection sensor 107. More specifically, the status detection unit 63 detects when the total waste toner 90 in the collection container 200 is full and when the total waste toner 90 in the collection container 200 is just short of being full. The state detection unit 63 detects the state that the collection container 200 is attached and the state that the collection container 200 is detached based on the detection signal from the attachment / detachment detection sensor 108. Therefore, the state detection unit 63 detects the state that the collection container 200 is full, that the collection container 200 is attached, and that the collection container 200 is detached. The state detection unit 63 also detects the state that the collection container 200 is just short of being full.

[0061] The prediction unit 64 predicts the amount of total waste toner 90 (see FIG. 2) in the print instruction replacement process described later (see step 504 in FIG. 11 described later). More specifically, the prediction unit 64 predicts the amount of discharged waste toner 92b (see FIG. 2), predicts the amount of untransferred waste toner, i.e., waste toner 91 (see FIG. 2) and waste toner 92a (see FIG. 2), and adds these together to predict the amount of total waste toner 90. The print order change unit 65 controls the execution of print instructions so that they are not executed in the order in which they were received, but rather in a reversed order in which they were received.

[0062] <Waste toner collection process> Next, a collection process of the waste toner 91, 92 (see FIG. 2) according to the state of the collection container 200 (see FIG. 2) will be described. FIG. 7 is a flowchart illustrating the waste toner collection process according to the state of the collection container 200 (see FIG. 2). 7, when a print instruction is received (step 101), assuming that collection container 200 has been removed and is being replaced, determination unit 61 (see FIG. 6) determines whether a clogging prevention switch that extends the time until waste toner clogging is ON (step 102). The clogging prevention switch is set ON when attachment / detachment detection sensor 108 (see FIG. 4) detects that collection container 200 has been removed.

[0063] If the jam prevention switch is ON (Yes in step 102), jam prevention control is performed (step 103), and the print instruction interruption determination process described below is performed to determine whether to interrupt the execution of the print instruction (step 104), and it is determined whether a predetermined cause for interrupting the print instruction exists (step 105). The determination in the print instruction interruption determination process includes interruption due to the amount of waste toner generated, as well as interruption by the user, interruption due to an error, interruption due to a lack of consumables, etc. The determination in the print instruction interruption determination process may also include measuring the elapsed time since the collection container 200 was removed and determining whether the elapsed time is equal to or greater than a predetermined value. On the other hand, if the clogging prevention switch is not ON (No in step 102 ), the process proceeds to step 104 .

[0064] If there is no cause for interrupting the print instruction (No in step 105), the print instruction is executed (step 106). On the other hand, if there is a reason for interrupting the print instruction (Yes in step 105), the process of interrupting the print instruction is carried out (step 107). When interrupting the print instruction, an error indicating the reason for the interruption may be displayed. After the print instruction is executed (step 106) or the print instruction is interrupted (step 107), the process returns to step 101.

[0065] In this embodiment, the waste toner recovery process is performed when a print instruction is received, but this is not limiting and it may be performed when the image forming apparatus 1 (see FIG. 1) is powered on. In such a case, if the clogging prevention switch is on (Yes in step 102), the print instruction interruption determination process (step 104) is performed and the process ends, and if the clogging prevention switch is not on (No in step 102), the process ends without any processing.

[0066] <Clogging prevention control> Next, the clogging prevention control (see step 103 in FIG. 7) will be described. FIG. 8 is a flowchart illustrating the clogging prevention control. 8, it is determined whether the total amount of waste toner in the collection container 200 (see FIG. 2) is close to the upper limit (step 201). This determination is made by the determination unit 61 (see FIG. 6) based on the result of the state detection by the state detection unit 63 (see FIG. 6).

[0067] If the total amount of waste toner is close to the upper limit of the amount of waste toner to be stored (Yes in step 201), a process for discharging the waste toner in the transfer device 102 is performed (step 202). That is, if the amount of waste toner in the collection container 200 (see FIG. 2) is close to the upper limit of the amount of waste toner to be stored, it is highly likely that the collection container 200 will need to be replaced. Therefore, the transfer pipes 112, 122, 142 and the tubular member 132 (see FIG. 2) in the transfer device 102 are used as a storage space for waste toner generated during replacement of the collection container 200 (see FIG. 2). For this reason, the waste toner in the transfer pipes 112, 122, 142 and the tubular member 132 (see FIG. 2) is discharged at a speed faster than normal and transferred to the collection container 200 (see FIG. 2). This makes it possible to use the transfer pipes 112, 122, 142 and the tubular member 132 in the transfer device 102 as a temporary storage space for waste toner generated during replacement of the collection container 200. Such temporary storage space may be referred to as the "storage space for the transport device 102."

[0068] More specifically, the drive control unit 62 (see FIG. 6) controls the drive unit 118 (see FIG. 2) to increase the rotational speed of the breaking member 117 (see FIG. 2) of the connection transfer device 115 (SY, SM, SC, SK, SA, SB). The drive control unit 62 (see FIG. 6) also controls the first drive unit 114 (see FIG. 2) to increase the rotational speed of the conveying member 113 (see FIG. 2) of the first transfer device 110, and controls the second drive unit 124 (see FIG. 6) to increase the rotational speed of the conveying member 123 (see FIG. 2) of the second transfer device 120. In addition, the drive control unit 62 (see Figure 6) controls the third drive device 134 (see Figure 2) to increase the rotational speed of the breaking member 133 (see Figure 2) of the third transfer device 130, and controls the fourth drive device 144 (see Figure 2) to increase the rotational speed of the conveying member 143 (see Figure 2) of the fourth transfer device 140. In this way, the drive control unit 62 (see FIG. 6) rotates the first drive unit 114, the drive unit 118, the second drive unit 124, the third drive unit 134, and the fourth drive unit 144 (see FIG. 2) at high speed.

[0069] Then, the determination unit 61 (see FIG. 6) determines the state of the collection container 200 (see FIG. 2). That is, it determines whether the collection container 200 is being replaced and whether the amount of waste toner in the collection container 200 has reached its upper limit (step 203). This determination is made by the determination unit 61 (see FIG. 6) based on the result of the state detection by the state detection unit 63. The determination unit 61 determines whether the result of the state detection by the state detection unit 63 satisfies the condition that the waste toner container 200 is being replaced or that the amount of waste toner in the waste toner container 200 has reached its upper limit.

[0070] Here, the result of the state detection by the state detection unit 63 (see FIG. 6) is an example of the result of the state detection of the storage container. Also, the fact that the collection container 200 is being replaced or that the amount of waste toner in the collection container 200 has reached its upper limit is an example of a predetermined case. The fact that the collection container 200 is removed is an example of a predetermined case. Furthermore, the fact that the amount of waste toner in the collection container 200 has reached the upper limit of the amount of collected developer in the collection container when the collection container is attached is an example of the amount of collected developer being a predetermined amount.

[0071] If the state of collection container 200 (see FIG. 2) corresponds to any one of the above (Yes in step 203), drive control section 62 (see FIG. 6) rotates first drive device 114, drive device 118, second drive device 124, third drive device 134, and fourth drive device 144 (see FIG. 2) at low speeds (step 204). That is, if high speed rotation was performed in step 202, the speed is changed to low speed rotation, and if high speed rotation was not performed in step 202, the low speed rotation is maintained. The amount of waste toner in the collection container 200 reaching its upper limit is an example of a case where the amount of collected developer that can be stored in the storage container is the upper limit, and the slow rotation by the drive control unit 62 (see Figure 6) is an example of control in which the motor that collects collected developer from the image forming unit rotates slower than when the collected developer in the storage container is not at its upper limit, and is an example of control in which the motor that collects collected developer from the image forming unit rotates slower than when a storage container is attached.

[0072] The determination unit 61 (see FIG. 6) determines whether or not there is a print instruction waiting to be executed or currently being executed among the received print instructions (see step 101 in FIG. 7) (step 205). If there is a print instruction waiting to be executed or currently being executed (Yes in step 205), a print instruction exchange process (details of which will be described later) is performed (step 206), and density adjustment is performed for the print instruction waiting to be executed or currently being executed (step 207).

[0073] In the print instruction replacement process (step 206), if there are print instructions waiting to be executed while the collection container 200 (see FIG. 2) is being replaced, the print order change unit 65 (see FIG. 6) prioritizes the print instructions that will result in less waste toner 92b due to toner discharge. This increases the number of print instructions that can be executed during the period until the collection container 200 is replaced. Details will be explained with reference to FIG. 11. The amount of waste toner 92b is calculated from the pixel count of each image, the paper size, and the like.

[0074] In addition, it is also possible to allow the user to set so that the print instruction swapping process (step 206) is not performed even when there is a print instruction waiting to be executed or being executed (Yes in step 205). In other words, the system is configured to be able to switch between changing the print order and not changing it. Even when such a setting is made, the density adjustment (step 207) is controlled to be performed.

[0075] Here, the density adjustment in step 207 will be explained. When low-density image data is printed in response to a print command, a large amount of waste toner is generated. Therefore, if there is a print command waiting to be executed or currently being executed because collection container 200 is being replaced, the density is increased by increasing the exposure amount for the print command determined to have a low density. This reduces the amount of waste toner discharged and reduces clogging of the waste toner transport path within transport device 102, i.e., transfer pipes 112, 122, 142 and tubular member 132 (see FIG. 2). It is also possible to adopt a configuration in which the user can set whether or not to perform density adjustment. Furthermore, density adjustment may be performed to increase the density not only when the image data in the print instruction is low density, but also when it is high density. Furthermore, as the density adjustment in step 207, when performing toner ejection to supply toner as a lubricant to the area outside the paper, control may be adopted to increase the amount of toner supplied to the area outside the paper for at least one of the current print instruction and the next print instruction.

[0076] Thereafter, the determining unit 61 (see FIG. 6) determines whether the collection container 200 has been replaced (step 208). If the collection container 200 has already been replaced (Yes in step 208), the drive control unit 62 (see FIG. 6) rotates the first drive device 114, the drive device 118, the second drive device 124, the third drive device 134, and the fourth drive device 144 (see FIG. 2) at high speed. As a result, any waste toner in the transfer device 102 that was generated during the replacement of the collection container 200 is quickly discharged after replacement (step 209) and transferred to the collection container 200. After a predetermined time has elapsed for discharging the waste toner in the preset transfer path, the fourth drive device 144 (see FIG. 2) is returned to medium speed rotation. This ends the clogging prevention control. If the collection container 200 has been replaced (see Yes in step 208), this is an example of a case where the result of the status detection has changed from detecting that the storage container has been removed to detecting that the storage container has been attached, and the high-speed rotation (see step 209) by the drive control unit 62 (see Figure 6) is an example of control in which the motor rotation is changed to a high speed.

[0077] If the amount of waste toner in collection container 200 (see FIG. 2) is not close to the upper limit (No in step 201), the process proceeds to step 203. If collection container 200 (see FIG. 2) is not being replaced and the amount of waste toner has not reached the upper limit (No in step 203), and if there is no print instruction waiting to be executed or currently being executed (No in step 205), the process proceeds to step 208. If collection container 200 has not been replaced (No in step 208), the clogging prevention control ends.

[0078] 8, when the amount of waste toner in the collection container 200 is full (Yes in step 203) or nearly full (Yes in step 201), the rotation speed is changed by the drive control unit 62. That is, the rotation speed of each of the drive devices 114, 118, 124, 134, and 144 is controlled according to the waste toner storage capacity of the collection container 200. To explain further, even if the collection container 200 has already been replaced (Yes in step 208), the rotation speed is changed by the drive control unit 62. Therefore, it can be said that the change in the rotation speed by the drive control unit 62 is performed in accordance with the detection result by the state detection unit 63.

[0079] <Print instruction interruption determination process> Next, the print instruction interruption determination process (see step 104 in FIG. 7) will be described. Note that the print instruction may be interrupted due to the amount of waste toner generated, interruption by the user, interruption due to the occurrence of an error, interruption due to a lack of consumables, etc. Below, the interruption due to the amount of waste toner generated will be described. FIG. 9 is a flowchart illustrating a process for determining whether to interrupt a print instruction based on the amount of waste toner generated. 9, the determination unit 61 (see FIG. 6) determines whether the amount of waste toner in the waste toner container 200 (see FIG. 2) is close to the upper limit (step 301). This determination is made based on the detection result of the fullness detection sensor 107 (see FIG. 4).

[0080] If the amount of waste toner is not close to the upper limit (No in step 301), the process returns to step 301. If the amount of waste toner is close to the upper limit (Yes in step 301), the prediction unit 64 calculates the predicted amount Ta of waste toner until the upper limit is reached in the storage space of the transfer device 102 (step 302). The calculation of the predicted amount Ta is performed by, for example, calculating the amount of toner consumption from pixel count and predicting the amount of waste toner from the transfer efficiencies of the primary and secondary transfers. The calculated predicted amount Ta of waste toner is saved in RAM 21c (see FIG. 4). The calculation of the predicted amount Ta of waste toner (see step 302) is an example of prediction of the amount of recovered developer in the path that transfers the recovered developer to the storage container.

[0081] Then, the determination unit 61 (see FIG. 6) determines the state of the waste toner container 200 (see FIG. 2). That is, it determines whether the amount of waste toner in the waste toner container 200 has reached the upper limit (step 303) and whether the waste toner container 200 is not yet installed (step 304). Whether the amount of waste toner has reached the upper limit of the storage capacity is determined based on the detection result of the fullness detection sensor 107 (see Figure 4), and whether the collection container 200 is not yet attached is determined based on the detection result of the attachment / detachment detection sensor 108 (see the same figure).

[0082] If the amount of waste toner in the collection container 200 has not reached the upper limit (No in step 303), it is determined whether the collection container 200 is not installed (step 304). If the collection container 200 is not installed (No in step 304), the process returns to step 303. If the amount of waste toner in the waste toner container 200 has reached the upper limit (Yes in step 303), the process proceeds to step 307, which will be described later.

[0083] If the waste toner container 200 is not installed (Yes in step 304), the waste toner generation amount calculation process described below is performed to calculate the waste toner generation amount Tb (step 305). In the waste toner generation amount calculation process, the toner consumption amount is calculated from the pixel count, and the amount of waste toner is calculated from the transfer efficiencies of the primary transfer and secondary transfer.

[0084] Then, the determining unit 61 (see FIG. 6) determines whether the amount of waste toner generated Tb in step 305 is greater than the predicted amount Ta until the storage upper limit is reached in step 302 (step 306). If the amount of waste toner generated Tb is greater than the predicted amount Ta until the upper limit of storage is reached (Yes in step 306), the process of interrupting the print instruction is executed (step 307). Also, as described above, if the amount of waste toner in the collection container 200 has reached its upper limit (see Yes in step 303), the current print instruction and the next print instruction are not executed, and the print instruction interruption process is executed (step 307).

[0085] The process of interrupting the print instruction includes notifying the user that the waste toner container 200 is full. In this way, the print instruction interruption determination process shown in Figure 9 predicts the amount of waste toner Tb generated by the print instruction currently being executed, and if it exceeds the predicted amount Ta that can be stored within the predetermined storage space of the transfer device 102, the print instruction currently being executed is interrupted.

[0086] <Waste Toner Generation Amount Calculation Process> Next, the waste toner generation amount calculation process (see step 305 in FIG. 9) will be described. FIG. 10 is a flowchart illustrating the waste toner generation amount calculation process. 10, it is determined whether printing of one line has been completed (step 401), and if printing has been completed (Yes in step 401), the toner consumption amount for one line is calculated based on the dot count value and edge count value (step 402). Such edge count value is taken into consideration in correspondence with the edge effect of the toner. If printing has not finished (No in step 401), the process returns to step 401.

[0087] Next, the fog toner consumption amount for one line is calculated (step 403). The fog toner consumption amount is the amount of toner consumed as toner that adheres to areas where no dots exist in the image data.

[0088] Then, the toner consumption amount for one line calculated in step 402 and the fog toner consumption amount for one line calculated in step 403 are added to the toner consumption amount for one image (step 404). Thereafter, the determination unit 61 (see FIG. 6) determines whether or not the imaging of one image has been completed (step 405). If the imaging of one image has not been completed (No in step 405), the process returns to step 401.

[0089] When the imaging of one image is completed (Yes in step 405), the primary transfer efficiency is calculated (step 406), and the secondary transfer efficiency is calculated (step 407). The primary transfer efficiency is the efficiency with which toner consumed for one image is transferred to the intermediate transfer belt 41 (see Figure 1) at the primary transfer section T1, in order to determine the amount of toner that is not transferred to the intermediate transfer belt 41 (see Figure 1) at the primary transfer section T1 and is removed by the drum cleaner 34, out of the toner consumed for one image. The secondary transfer efficiency is the efficiency with which toner is transferred onto the paper P at the secondary transfer portion T2.

[0090] Then, the amount of waste toner per image is calculated from the toner consumption amount for one image, the primary transfer efficiency (%), and the secondary transfer efficiency (%) (step 408). Next, the amount of waste toner per image is added to the cumulative amount of waste toner (step 409). Then, it is determined whether printing of all images has been completed (step 410). If printing has not been completed (No in step 410), the process returns to step 401; if printing has been completed (Yes in step 410), the process ends.

[0091] <Print instruction replacement process> Next, the print instruction exchange process (see step 206 in FIG. 8) will be described. 11 is a flowchart illustrating the print instruction switching process. In this flowchart, the print order change unit 65 (see FIG. 6) calculates the toner discharge amount for the print instructions waiting to be executed before executing the next print instruction, and determines the print instruction to be executed.

[0092] In the example shown in FIG. 11, the determination unit 61 (see FIG. 6) determines whether or not there is a next print instruction (step 501). If there is a next print instruction (Yes in step 501), the process determines the print order for the current print instruction and the next print instruction by comparing the total amount of waste toner for each. As described above, the total amount of waste toner is the sum of the amount of untransferred waste toner and the amount of discharged waste toner.

[0093] First, the prediction unit 64 (see FIG. 6) performs a discharged waste toner amount calculation process (described later) to calculate the amount of discharged waste toner 92b (see FIG. 2) (step 502), and calculates the amount of untransferred waste toner (step 503). Then, the amount of discharged waste toner 92b and the amount of untransferred waste toner are added together to calculate the total amount of waste toner (step 504). The calculation of the total amount of waste toner is performed for each print instruction.

[0094] The amount of discharged waste toner 92b (see step 502) is an example of the amount of developer supplied to a predetermined area, and the amount of untransferred waste toner is an example of the amount of untransferred developer. The calculation of the total amount of waste toner is an example of prediction of the amount of recovered developer that will be recovered in response to the execution of a received print instruction, and is an example of prediction of the amount of recovered developer.

[0095] Next, the determination unit 61 (see FIG. 6) determines whether the total amount of waste toner for the current print instruction is greater than the total amount of waste toner for the next print instruction (step 505). If the total amount of waste toner for the current print instruction is greater than the total amount of waste toner for the next print instruction (Yes in step 505), the print order change unit 65 (see FIG. 6) switches the print order of the current print instruction and the next print instruction (step 506). That is, if the calculated total amount of waste toner (see step 504) for the next print instruction is less than that for the current print instruction, the print order is changed so that the next print instruction is printed before the current print instruction. After the print order is changed, the process ends.

[0096] In this way, the printing order is changed so that the next print instruction, which has a smaller total amount of waste toner, is printed before the current print instruction, which has a larger total amount of waste toner. If the current print instruction, which has a large total amount of waste toner, is printed first, there is a high possibility that it will be interrupted midway. If the current print instruction is interrupted midway, the next print instruction will also be unable to be executed. Therefore, by printing the print instruction with a smaller total amount of waste toner before the print instruction with a larger total amount of waste toner, it is possible to increase the number of print instructions that are completed as much as possible. In this way, by rearranging the printing order, it is possible to prevent the current print instruction from being interrupted midway. The current print instruction is an example of a first print instruction, and the next print instruction is an example of a second print instruction. When three or more print instructions are used, the print instruction with the largest total amount of waste toner may be used first.

[0097] If the total amount of waste toner for the current print instruction is not greater than the total amount of waste toner for the next print instruction (No in step 505), the print order is not changed and the process ends.

[0098] In this way, in the print instruction replacement process, when the collection container 200 is being replaced and there are print instructions waiting to be executed, it is determined whether the image data of each print instruction has a low coverage, which is a relatively low density, or a high coverage, which is a relatively high density. A common method for determining whether the image data has a low density is to compare the pixel count of the image with a threshold value for determining whether toner should be discharged. In the case of low coverage, toner discharge is required to prevent toner with deteriorated chargeability from remaining in the developing unit 33 (see Figure 1), resulting in an increase in waste toner. For this reason, the execution order of a print instruction determined to be low coverage is swapped with that of a high coverage print instruction, and the high coverage print instruction is executed first, delaying the generation of a large amount of waste toner. Note that the execution order can also be swapped based on the difference in density between the previous and next instructions.

[0099] Here, the above-described print instruction exchange process for calculating the total amount of waste toner (see step 504) and changing the print order (see step 506) is performed when the collection container 200 is being replaced or when the amount of waste toner is at its upper limit (see "Yes" in step 203 of FIG. 8). However, this is not limited to this, and modified examples can be considered. As such a modified example, for example, when the amount of waste toner in the collection container 200 is close to its upper limit (see "Yes" in step 201 of FIG. 8), the total amount of waste toner may be calculated (see step 504) and the print order may be changed (see step 506) in addition to the discharge process (step 202). This makes it possible to prevent the execution of print instructions from being canceled even if the collection container 200 is subsequently removed. In such a modified example, when the amount of waste toner is close to the upper limit of the amount of recovered toner that can be stored in the storage container, this is an example of a case where the amount is less than the upper limit of the amount of recovered developer that can be stored in the storage container, and the high-speed rotation by the drive control unit 62 is an example of control in which the motor that recovers recovered developer from the image forming unit rotates faster than when the amount of recovered developer in the storage container has not reached the upper limit of the amount that can be stored.

[0100] <Calculation of the amount of discharged waste toner> Next, the discharged waste toner amount calculation process (see step 502 in FIG. 11) will be described. FIG. 12 is a diagram for explaining the discharged waste toner amount calculation process, where (a) is a flowchart and (b) is a table used in the flowchart of (a). In the example shown in FIG. 12(a), after the low density determination of the print instruction is performed, the size of the paper P (see FIG. 1) is determined. To determine whether a print command is low density, first, the pixel count of the image in the print command is obtained (step 601), and the first discharge waste toner amount is determined based on the obtained pixel count and the table (step 602).

[0101] The table here indicates the relationship between the pixel count (X) and the amount of discharged and discarded toner, as shown in FIG. 12(b). When the pixel count (X) is less than X1, which is low area coverage, the amount of discharged waste toner is Y1% of the pixel count (X). When the pixel count (X) is equal to or greater than X1% and less than X2, which is medium area coverage, the amount of discharged waste toner is Y2% of the pixel count (X). When the pixel count (X) is equal to or greater than X2% and less than X3, which is high area coverage, the amount of discharged waste toner is Y3% of the pixel count (X). When the pixel count (X) is equal to or greater than X3%, the amount of discharged waste toner is Y4% of the pixel count (X). Note that the magnitude relationship is Y1%>Y2%>Y3%>Y4%. Y4% may be, for example, 0%.

[0102] Returning to FIG. 12(a), the explanation will be continued. Next, to determine the size of the paper P (see FIG. 1), the paper width size is acquired (step 603), and the determination unit 61 (see FIG. 6) determines whether the paper width size is smaller than a predetermined threshold value (step 604). If the paper width size is smaller than a predetermined threshold (Yes in step 604), the second discharge amount of waste toner is determined based on the paper width size, etc. (step 605); if not (No in step 604), the second discharge amount of waste toner is determined to be 0 (step 606). Then, the first amount of discharged waste toner (see step 602) determined by the low density determination of the print instruction is added to the second amount of discharged waste toner determined by the size determination of the paper P (see Figure 1) to calculate the amount of discharged waste toner to be used in step 502 (see Figure 11) (step 607).

[0103] When discharging toner to supply toner as a lubricant to the area outside the paper, control may be adopted to increase the amount of toner for at least one of the current print instruction and the next print instruction. In calculating the amount of toner to be discharged and discarded, if control to increase the amount of toner is adopted, the amount of toner to be discharged and discarded will be large (see step 607).

[0104] <Additional Notes> (((1))) a processor; The processor: When the result of detecting the state of a container that stores recovered developer collected in association with forming an image with the developer is predetermined, the amount of recovered developer to be collected in association with the execution of the received print instruction is predicted; receiving a second print instruction as the print instruction after receiving a first print instruction, and if the predicted amount of recovered developer for the second print instruction is less than that for the first print instruction, changing the print order so that the second print instruction is printed before the first print instruction. Image forming device. (((2))) The predetermined amount is a predetermined amount of recovered developer in the storage container when the storage container is attached. The image forming apparatus according to (((1))) is characterized in that (((3))) the predetermined amount is less than the upper limit of the amount of recovered developer that can be stored in the storage container, a motor for recovering the recovered developer from the image forming unit rotates at a higher speed than when the amount of the recovered developer in the container has not reached the small amount; The image forming apparatus according to (((2))) is characterized in that (((4))) the predetermined amount is the upper limit of the amount of recovered developer that can be stored in the storage container, a motor for recovering the recovered developer from the image forming unit rotates at a slower speed than when the amount of recovered developer in the container is not at the upper limit; The image forming apparatus according to (((2))) is characterized in that (((5))) The predetermined case is that it has been detected that the storage container has been removed. The image forming apparatus according to (((1))) is characterized in that (((6))) a motor for recovering the recovered developer from the image forming unit rotates at a slower speed than when the developer container is attached; The image forming apparatus according to (((5))) is characterized in that (((7))) When the result of the state detection changes from detection that the container is removed to detection that the container is attached, the rotation speed of the motor is changed to a high speed. The image forming apparatus according to (((6))) is characterized in that (((8))) When the image formed by the developer according to the print instruction satisfies a predetermined condition, the developer is supplied to a predetermined area regardless of the print instruction. the amount of recovered developer is predicted based on the amount of developer that remains untransferred when an image formed by the developer is transferred to a recording medium and the amount of developer that is supplied to the predetermined area; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus comprises: (((9))) increasing the amount of developer supplied to the predetermined area for at least one of the first print instruction and the second print instruction; The image forming apparatus according to (((8))) is characterized in that (((10))) predicting an amount of recovered developer in a path for transferring the recovered developer to a storage container, and not carrying out the first print instruction and the second print instruction when the result of the prediction is an upper limit; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus comprises: (((11))) It is possible to switch between a case where the printing order is changed and a case where the printing order is not changed. 10. The image forming apparatus according to claim 1, wherein the image forming apparatus comprises: (((12))) In the information processing device, a function of predicting the amount of recovered developer to be recovered in accordance with the execution of a received print instruction when the result of detecting the state of a container that stores recovered developer recovered in accordance with the formation of an image with developer is predetermined; a function of accepting a second print instruction as the print instruction after accepting a first print instruction, and changing the print order so that the second print instruction is printed before the first print instruction when the predicted amount of recovered developer for the second print instruction is less than that for the first print instruction; A program to make this happen.

[0105] According to the invention (((1))), it is possible to prevent the execution of a print instruction from being canceled due to the amount of recovered developer, compared to when the print instructions are executed in the order of receipt, regardless of the amount of recovered developer recovered in conjunction with the execution of the received print instruction and the state of the storage container that contains the recovered developer. According to the invention of (((2))), when it is predetermined, it is possible to prevent the occurrence of a situation in which the execution of a print instruction is interrupted due to the amount of recovered developer, compared to a case in which the configuration is not provided in which the amount of recovered developer in the storage container when the storage container is attached is a predetermined amount. According to the invention of (((3))), when the predetermined amount is less than the upper limit of the amount of recovered developer that can be stored in the storage container, the motor that recovers recovered developer from the image forming unit can be prevented from canceling the execution of a print instruction even if the storage container is subsequently removed, compared to when the motor is not configured to rotate at a higher speed than when the amount of recovered developer in the storage container has not reached a low level. According to the invention of (((4))), when the predetermined amount is the upper limit of the amount of recovered developer that can be stored in the storage container, the number of print instructions that can be executed can be increased compared to when the motor that recovers the recovered developer from the image forming unit is not configured to rotate at a slower speed than when the recovered developer in the storage container is not at the upper limit. According to the invention of (((5))), in a predetermined case, it is possible to prevent the occurrence of a situation in which the execution of a print instruction is interrupted due to the amount of recovered developer after the storage container is removed, compared to a case in which the configuration is not provided in which the removal of the storage container is detected. According to the invention (((6))), the motor that recovers recovered developer from the image forming unit rotates at a slower speed than when a storage container is attached, and the number of print instructions that can be executed can be increased compared to when the motor is not configured to rotate at a slower speed than when a storage container is attached. According to the invention of (((7))), when the result of the state detection changes from detecting that the storage container is removed to detecting that the storage container is attached, the rotation of the motor is changed to high speed, and the recovered developer in the transport path to the storage container can be transported to the storage container more quickly than in a case where the configuration is not provided. According to the invention of (((8))), when an image formed by developer according to a print instruction satisfies predetermined conditions and developer is supplied to a predetermined area without a print instruction, the accuracy of the prediction of the amount of recovered developer can be improved compared to when the configuration is not provided in which the prediction is based on the amount of developer that is not transferred when an image formed by developer is transferred to a recording medium and the amount of developer that is supplied to the predetermined area. According to the invention (((9))), the amount of recovered developer can be reduced compared to a case where the configuration for increasing the amount of developer supplied to a predetermined area is not provided for at least one of the first print instruction and the second print instruction. According to the invention of (((10))), the amount of recovered developer in the path that transports the recovered developer to a storage container is predicted, and if the predicted result is at the upper limit, it is possible to avoid a situation in which a print instruction being executed is interrupted midway, compared to a case in which the configuration is not provided that does not execute the first print instruction and the second print instruction. According to the invention of (((11))), it is possible to provide the user with more options than when there is no configuration that allows switching between changing the printing order and not changing the printing order. According to the invention (((12))), it is possible to prevent the execution of a print instruction from being canceled due to the amount of recovered developer, compared to when the print instructions are executed in the order of receipt, regardless of the amount of recovered developer recovered in conjunction with the execution of the received print instruction and the state of the storage container that contains the recovered developer. [Explanation of symbols]

[0106] 1...image forming apparatus, 21a...arithmetic processing unit, 21b...CPU, 34...drum cleaner, 45...belt cleaner, 61...determination unit, 62...drive control unit, 63...status detection unit, 64...prediction unit, 65...print order change unit, 90...total waste toner, 91, 92, 92a, 92b...waste toner, 100...waste toner recovery system, 102...transport device, 107...full detection sensor, 108 ...attachment / detachment detection sensor, 110...first transfer device, 112...first transfer pipe, 114...first drive device, 116...tubular member, 118...drive device, 120...second transfer device, 122...second transfer pipe, 124...second drive device, 130...third transfer device, 132...tubular member, 134...third drive device, 140...fourth transfer device, 142...fourth transfer pipe, 144...fourth drive device, 200...collection container

Claims

1. a processor; The processor: When the result of detecting the state of a container that stores recovered developer collected in association with forming an image with the developer is predetermined, the amount of recovered developer to be collected in association with the execution of the received print instruction is predicted; receiving a second print instruction as the print instruction after receiving a first print instruction, and if the predicted amount of recovered developer for the second print instruction is less than that for the first print instruction, changing the print order so that the second print instruction is printed before the first print instruction. Image forming device.

2. The predetermined amount is a predetermined amount of recovered developer in the storage container when the storage container is attached.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. the predetermined amount is less than the upper limit of the amount of recovered developer that can be stored in the storage container, a motor for recovering the recovered developer from the image forming unit rotates at a higher speed than when the amount of the recovered developer in the container has not reached the small amount; 3. The image forming apparatus according to claim 2, wherein the image forming apparatus is a recording medium.

4. the predetermined amount is the upper limit of the amount of recovered developer that can be stored in the storage container, a motor for recovering the recovered developer from the image forming unit rotates at a slower speed than when the amount of recovered developer in the storage container is not at the upper limit; 3. The image forming apparatus according to claim 2, wherein the image forming apparatus is a recording medium.

5. The predetermined case is that it has been detected that the storage container has been removed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. a motor for recovering the recovered developer from the image forming unit rotates at a slower speed than when the developer container is attached; 6. The image forming apparatus according to claim 5,

7. When the result of the state detection changes from detection that the container is removed to detection that the container is attached, the rotation speed of the motor is changed to a high speed.

7. The image forming apparatus according to claim 6,

8. When the image formed by the developer according to the print instruction satisfies a predetermined condition, the developer is supplied to a predetermined area regardless of the print instruction. the amount of recovered developer is predicted based on the amount of developer that remains untransferred when an image formed by the developer is transferred to a recording medium and the amount of developer that is supplied to the predetermined area; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. increasing the amount of developer supplied to the predetermined area for at least one of the first print instruction and the second print instruction; 9. The image forming apparatus according to claim 8,

10. predicting an amount of recovered developer in a path for transferring the recovered developer to a storage container, and not carrying out the first print instruction and the second print instruction when the result of the prediction is an upper limit; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

11. It is possible to switch between a case where the printing order is changed and a case where the printing order is not changed.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

12. In the information processing device, a function of predicting the amount of recovered developer to be recovered in accordance with the execution of a received print instruction when the result of detecting the state of a container that stores recovered developer recovered in accordance with the formation of an image with developer is predetermined; a function of accepting a second print instruction as the print instruction after accepting a first print instruction, and changing the print order so that the second print instruction is printed before the first print instruction when the predicted amount of recovered developer for the second print instruction is less than that for the first print instruction; A program to make this happen.

Images