Information processing systems and information processing programs

Abstract

This device supplements the current flowing from the primary transfer unit to the secondary transfer unit via the intermediate transfer belt during image transfer to the image recording medium. [Solution] The information processing system 80 includes at least one processor, which calculates a correction coefficient based on the voltage measurement of the primary transfer section 33 in a first state in which the primary transfer section 33 and secondary transfer section 34 in contact with the intermediate transfer belt of the image forming apparatus 80A are subjected to voltages of the same polarity, and the voltage measurement of the primary transfer section 33 in a second state in which the primary transfer section 33 and secondary transfer section 34 are subjected to voltages of opposite polarity with the same current flowing through the primary transfer section 33 as in the first state, and uses the correction coefficient to adjust the primary transfer current that flows through the primary transfer section 33 when transferring an image to an image recording medium.

Description

Technical Field

[0001] The present disclosure relates to an information processing system and an information processing program.

Background Art

[0002] In a transfer device including a primary transfer unit and a secondary transfer unit to which transfer biases having different polarities are applied, current interference between the transfer units may occur. In such a case, current may flow from the primary transfer unit to the secondary transfer unit, resulting in transfer failure. Patent Document 1 below describes a transfer device provided with a grounding portion where an intermediate transfer belt and the ground are connected between the primary transfer unit and the secondary transfer unit. This prevents current interference between the transfer units.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure compensates for the current flowing from the primary transfer unit to the secondary transfer unit via the intermediate transfer belt during image transfer to an image recording medium.

Means for Solving the Problems

[0005] An information processing system according to a first aspect includes at least one processor. The processor calculates a correction coefficient based on a voltage measurement value of the primary transfer unit in a first state in which the same-polarity voltage is applied to the primary transfer unit and the secondary transfer unit that contact the intermediate transfer belt of the image forming apparatus, and a voltage measurement value of the primary transfer unit in a second state in which reverse-polarity voltages are applied to the primary transfer unit and the secondary transfer unit with the same current as that in the first state flowing through the primary transfer unit, and adjusts the primary current during transfer flowing through the primary transfer unit during image transfer to an image recording medium using the correction coefficient.

[0006] In the second embodiment of the information processing system, the processor in the first embodiment flows a current that applies an equal voltage to the primary transfer unit and the secondary transfer unit in the first state.

[0007] In the third embodiment of the information processing system, in the first embodiment of the information processing system, the processor, in the first state, flows the primary current during transfer before adjustment to the primary transfer unit.

[0008] In the fourth embodiment of the information processing system, in the second embodiment of the information processing system, the processor adjusts the current flowing through the secondary transfer section in the first state to apply a voltage equal to that of the primary transfer section to the secondary transfer section.

[0009] In the fifth embodiment of the information processing system, in the information processing system of the second embodiment, if the voltage when the primary current during transfer is passed through the primary transfer section is equal to or greater than a predetermined reference voltage, the processor adjusts the current flowing through the secondary transfer section in the first state to apply a voltage equal to that of the primary transfer section to the secondary transfer section.

[0010] The sixth embodiment of the information processing system is an information processing system in the first embodiment in which, if the voltage when the primary current during transfer is passed through the primary transfer section is less than a predetermined reference voltage, the processor in the first state passes the primary current during transfer through the primary transfer section and passes a current to the secondary transfer section that applies the reference voltage.

[0011] The seventh aspect of the information processing system is an information processing system in the second aspect, in which the processor, when the voltage when the primary current during transfer is passed through the primary transfer section is less than a predetermined reference voltage, adjusts the current flowing through the primary transfer section in the first state to apply the reference voltage to the primary transfer section, which is equal to the voltage of the secondary transfer section.

[0012] The information processing system of the eighth embodiment, in the information processing system of the second embodiment, if the voltage when the primary current during transfer is passed through the primary transfer section is less than a predetermined reference voltage, the processor adjusts the current flowing through the secondary transfer section in the first state to apply a voltage equal to that of the primary transfer section to the secondary transfer section, and after calculating the correction coefficient, adjusts the current flowing through the secondary transfer section to apply a voltage equal to or greater than the reference voltage to the secondary transfer section to clean the secondary transfer section.

[0013] The ninth aspect of the information processing system, in the information processing system of the seventh aspect, when the processor accepts a subsequent job involving image transfer to the image recording medium, in the first state, adjusts the current flowing to the primary transfer section to apply the reference voltage to the primary transfer section, which is equal to the voltage of the secondary transfer section. When the processor does not accept a subsequent job involving image transfer to the image recording medium, in the first state, adjusts the current flowing to the secondary transfer section to apply the same voltage to the secondary transfer section as the primary transfer section. After calculating the correction coefficient, the processor adjusts the current flowing to the secondary transfer section to apply a voltage equal to or greater than the reference voltage to the secondary transfer section to clean the secondary transfer section.

[0014] In the tenth embodiment of the information processing system, in the second embodiment of the information processing system, the processor, when the difference between a predetermined reference voltage and the voltage when the primary current during transfer is passed through the primary transfer unit is greater than a threshold, flows a current that applies an equal voltage to the primary transfer unit and the secondary transfer unit in the first state.

[0015] The information processing system of the eleventh embodiment, in the information processing system of the first embodiment, wherein the processor flows the primary current during transfer to the primary transfer unit before the first state and the second state, and obtains the voltage of the primary transfer unit.

[0016] In the twelfth embodiment of the information processing system, in the first embodiment of the information processing system, the processor calculates the correction coefficient based on the voltage measurement value of the primary transfer portion closest to the secondary transfer portion on the upstream side in the circumferential direction of the intermediate transfer belt when there are multiple primary transfer portions in contact with the intermediate transfer belt.

[0017] The information processing program of the thirteenth embodiment calculates a correction coefficient based on the voltage measurement of the primary transfer section in a first state in which the same polarity voltage is applied to the primary transfer section and the secondary transfer section in contact with the intermediate transfer belt of the image forming apparatus, and the voltage measurement of the primary transfer section in a second state in which the same current as in the first state is applied to the primary transfer section and the primary transfer section and the secondary transfer section are subjected to voltages of opposite polarity, and causes the computer to adjust the primary transfer current that flows through the primary transfer section when transferring an image to an image recording medium using the correction coefficient. [Effects of the Invention]

[0018] According to the information processing system of the first embodiment and the information processing program of the thirteenth embodiment, the current flowing from the primary transfer unit to the secondary transfer unit via the intermediate transfer belt during image transfer to an image recording medium can be supplemented.

[0019] According to the information processing system of the second embodiment, the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary transfer unit and the secondary transfer unit are different.

[0020] According to the third embodiment of the information processing system, the accuracy of the correction coefficient is higher compared to the case where a current different from the primary current during transfer is passed through the primary transfer section to calculate the correction coefficient.

[0021] According to the information processing system of the fourth embodiment, the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary transfer unit and the secondary transfer unit are different.

[0022] According to the information processing system of the fifth embodiment, cleaning of the secondary transfer section, which is required when the voltage applied to the secondary transfer section is less than the reference voltage, becomes unnecessary.

[0023] According to the information processing system of the sixth aspect, the secondary transfer unit can be cleaned by a reference voltage.

[0024] According to the information processing system of the seventh aspect, when the voltage applied to the secondary transfer unit is less than the reference voltage, cleaning of the secondary transfer unit, which is required otherwise, becomes unnecessary.

[0025] According to the information processing system of the eighth aspect, the accuracy of the correction coefficient is higher as compared with the case where a current different from the primary transfer current at the time of transfer is passed through the primary transfer unit to calculate the correction coefficient. Further, the secondary transfer unit can be cleaned.

[0026] According to the information processing system of the ninth aspect, the secondary transfer unit can be cleaned when a plurality of jobs involving image transfer to an image recording medium are not instructed to be executed.

[0027] According to the information processing system of the tenth aspect, the accuracy of the correction coefficient is higher as compared with the case where the voltages applied to the primary transfer unit and the secondary transfer unit are different.

[0028] According to the information processing system of the eleventh aspect, the voltage applied to the primary transfer unit when a primary transfer current is passed through can be confirmed.

[0029] According to the information processing system of the twelfth aspect, the current flowing from the primary transfer unit closest to the secondary transfer unit to the secondary transfer unit can be compensated.

Brief Description of the Drawings

[0030] [Figure 1] It is a schematic diagram showing an example of the overall configuration of the information processing system of the present disclosure. [Figure 2] It is a block diagram showing an example of the electrical configuration of the control device in the information processing system of the present disclosure. [Figure 3] It is a block diagram showing an example of the functional configuration of the control device in the information processing system of the present disclosure. [Figure 4]This table shows an example of a current adjustment process in the information processing system disclosed herein. [Figure 5] This flowchart shows an example of current adjustment processing in the information processing system disclosed herein. [Modes for carrying out the invention]

[0031] Hereinafter, an information processing system and information processing program according to the embodiments of this disclosure will be described with reference to the drawings. Components indicated by the same reference numerals in each drawing are considered to be the same component. However, unless otherwise specified in the specification, each component is not limited to one, and there may be multiple such components.

[0032] Furthermore, explanations of redundant components and reference numerals in each drawing may be omitted. This disclosure is not limited to the following embodiments. Various embodiments can be implemented with appropriate modifications, such as omitting components, substituting different components, or combining one embodiment with various modifications, within the scope of the purpose of this disclosure.

[0033] <Information Processing System> The information processing system 80 shown in Figure 1 is a system built into the image forming apparatus 80A. In this disclosure, "system" includes systems composed of a single device. Furthermore, in this disclosure, "system" also includes systems composed of multiple devices, and systems built into higher-level devices or systems.

[0034] In other words, the information processing system disclosed herein may be constructed across multiple devices other than the image forming apparatus 80A. For example, the information processing system 80 of this embodiment may be constructed including a server that can communicate with the image forming apparatus 80A, or other image forming apparatuses connected via a network.

[0035] Furthermore, the various processes performed by the information processing system 80 can also be executed in the cloud, on-premise servers, edge servers, endpoints, etc. In addition, this disclosure is also applicable to programs and program products.

[0036] <Overall configuration of the image forming apparatus> Figure 1 is a schematic diagram showing the configuration of the image forming apparatus 80A as viewed from the front. In Figure 1, the direction indicated by arrow H is the vertical direction, and the direction indicated by arrow W is the horizontal direction, which is the width direction of the apparatus.

[0037] As shown in Figure 1, the image forming apparatus 80A includes an image forming unit 12 that forms an image on a sheet of paper P, which is an example of an image recording medium, using an electrophotographic method; a transport device 50 that transports the sheet of paper P; and a control device 10 that controls the operation of each part of the image forming apparatus 80A. The image forming apparatus 80A is also equipped with a sensor 46 that detects temperature and humidity.

[0038] <Conveying device 50> As shown in Figure 1, the conveying device 50 has a container 51 in which the paper P is stored. The conveying device 50 also has a plurality of conveying rolls 52, 53 that convey the paper P from the container 51 to the secondary transfer position NT. Furthermore, the conveying device 50 has a conveying belt 58 that conveys the paper P from the secondary transfer position NT to the fixing device 40, which will be described later.

[0039] <Image forming unit 12> The image forming unit 12 includes a toner image forming unit 20 that forms a toner image. The image forming unit 12 also includes a transfer device 30 that transfers the toner image formed by the toner image forming unit 20 onto paper P. Furthermore, the image forming unit 12 includes a fixing device 40 that heats and pressurizes the toner image transferred to paper P to fix it to the paper P. The toner image forming unit 20 is an example of an image forming unit.

[0040] (Toner image forming unit 20) Multiple toner image forming units 20 are provided to form toner images for each color. In this embodiment, a total of four toner image forming units 20 are provided for yellow (Y), magenta (M), cyan (C), and black (K). These toner image forming units 20 for each color are arranged in the order of yellow (Y), magenta (M), cyan (C), and black (K), from the upstream side to the downstream side in the transport direction of the intermediate transfer belt 31, which will be described later.

[0041] Figure 1 shows (Y), (M), (C), and (K) to indicate the component parts corresponding to each of the above colors. In this specification, the parentheses around (Y), (M), (C), and (K) may be omitted, and they may be written as Y, M, C, and K.

[0042] Each toner image forming unit 20 is basically configured similarly, except for the toner used. Specifically, each toner image forming unit 20 has a photoreceptor drum 21 that rotates clockwise as indicated by the arrow. The toner image forming unit 20 also has a charger 22 for charging the photoreceptor drum 21. The toner image forming unit 20 also has an exposure device 23. The exposure device 23 exposes the photoreceptor drum 21, which has been charged by the charger 22, to form an electrostatic latent image on the photoreceptor drum 21. Furthermore, each toner image forming unit 20 has a developing device 24. The developing device 24 develops the electrostatic latent image formed on the photoreceptor drum 21 by the exposure device 23 to form a toner image. The toner image forming unit 20 also has a cleaning device 25. The cleaning device 25 is equipped with a blade 25A that removes toner remaining on the surface of the photoreceptor drum 21 after the toner image has been transferred to the transfer device 30.

[0043] The charger 22, for example, negatively charges the surface (photosensitive layer) of the photoreceptor drum 21. The negatively charged surface of the photoreceptor drum 21 exhibits positive polarity in the area irradiated with exposure light L by the exposure device 23, and an electrostatic latent image is formed on the surface of the photoreceptor drum 21. Then, toner that has been negatively frictionally charged in the developing device 24 adheres to the positively polarized electrostatic latent image, and the electrostatic latent image is developed. In this way, a toner image is formed on the surface (outer surface) of the photoreceptor drum 21. The blade 25A contacts the surface of the photoreceptor drum 21 and scrapes off the toner remaining on the surface of the photoreceptor drum 21.

[0044] (Transfer device 30) The transfer device 30 performs primary transfer by superimposing the toner images of each color photoreceptor drum 21 onto the intermediate transfer belt 31. The transfer device 30 then performs secondary transfer of the superimposed toner images onto the paper P at the secondary transfer position NT. Specifically, the transfer device 30 comprises an intermediate transfer belt 31 that holds the toner images, a primary transfer roll 33A, and a secondary transfer section 34 equipped with a secondary transfer belt 36. The secondary transfer position NT is an example of a transfer position.

[0045] • Intermediate transfer belt 31 As shown in Figure 1, the intermediate transfer belt 31 is endless and its orientation is determined by being wrapped around the drive roll 32D, the tensioning roll 32T, and the opposing roll 32B. In the first embodiment, the intermediate transfer belt 31 is positioned as an inverted obtuse triangle, which is long in the width direction of the device when viewed from the front. The device may also be provided with other rolls around which the intermediate transfer belt 31 is wrapped.

[0046] The drive roll 32D rotates the intermediate transfer belt 31 in the direction of arrow A using power from a motor (not shown). By rotating in the direction of arrow A, the intermediate transfer belt 31 transports the toner image transferred in the primary transfer to the secondary transfer position NT. As an example, the drive roll 32D is positioned upstream of the four primary transfer rolls 33A in the rotational direction of the intermediate transfer belt 31. The tension-applying roll 32T applies tension to the intermediate transfer belt 31.

[0047] Furthermore, the opposing roll 32B is a roll that faces the secondary transfer roll 60, which will be described later. The upper end of the obtuse angle of the intermediate transfer belt 31, which is positioned in an inverted obtuse-angled triangular shape, is wrapped around the opposing roll 32B. The upper edge of this intermediate transfer belt 31, which extends in the width direction of the apparatus in the aforementioned orientation, is in contact with the photosensitive drums 21 of each color from below.

[0048] A cleaning device 35 for removing toner remaining on the intermediate transfer belt 31 is provided downstream of the secondary transfer position NT in the circumferential direction of the intermediate transfer belt 31 and upstream of the primary transfer position T(K). As an example, the cleaning device 35 comprises a cleaning brush 35A, a blade 35B, and a scraper 35C. The cleaning brush 35A removes toner from the surface of the intermediate transfer belt 31 by rotating while in contact with the surface of the intermediate transfer belt 31. The blade 35B is positioned downstream of the cleaning brush 35A in the circumferential direction of the intermediate transfer belt 31. The blade 35B contacts the intermediate transfer belt 31 and scrapes off toner from the surface of the intermediate transfer belt 31. The scraper 35C is positioned downstream of the blade 35B in the circumferential direction of the intermediate transfer belt 31. The scraper 35C contacts the intermediate transfer belt 31 and scrapes off toner from the surface of the intermediate transfer belt 31 that could not be removed by the cleaning brush 35A and the blade 35B.

[0049] For example, the circumference of the intermediate transfer belt 31 is 1200 mm, the width in the direction perpendicular to the direction of movement is 370 mm, and the thickness of the intermediate transfer belt 31 is between 50 μm and 100 μm. Also, for example, the intermediate transfer belt 31 has a structure in which carbon is dispersed in polyimide resin.

[0050] • Primary transfer section 33 As shown in Figure 1, the primary transfer unit 33 is equipped with a primary transfer roll 33A. The primary transfer roll 33A is a roll that transfers the toner image from each photoreceptor drum 21 to the intermediate transfer belt 31. The primary transfer roll 33A is located inside the intermediate transfer belt 31. Each primary transfer roll 33A is positioned opposite the corresponding color photoreceptor drum 21, with the intermediate transfer belt 31 in between. A variable power supply 72 is connected to the primary transfer roll 33A. The variable power supply 72 is a power supply capable of varying a constant DC voltage and constant current. A current measuring element 71 and a voltage measuring element 73 are connected to the wiring 72A between the primary transfer roll 33A and the variable power supply 72. The current measuring element 71 measures the current in the primary transfer unit 33. The voltage measuring element 73 measures the voltage in the primary transfer unit 33.

[0051] In Figure 1, the variable power supply 72, wiring 72A, current measuring element 71, and voltage measuring element 73 are connected only to the primary transfer roll 33A closest to the secondary transfer section 34. The variable power supply 72, wiring 72A, current measuring element 71, and voltage measuring element 73 connected to the other transfer rolls 33A are not shown.

[0052] The primary transfer roll 33A is supplied with a primary transfer voltage opposite to the toner polarity by a variable power supply 72. In other words, because the toner is triboelectrically charged with negative polarity, a positive primary transfer voltage is applied to the primary transfer roll 33A. This application of primary transfer voltage transfers the toner image formed on the photoreceptor drum 21 to the intermediate transfer belt 31. The toner image is transferred to the intermediate transfer belt 31 at the primary transfer position T between the photoreceptor drum 21 and the primary transfer roll 33A.

[0053] • Secondary transfer section 34 The secondary transfer unit 34 includes a secondary transfer belt 36, a secondary transfer roll 60 and a driven roll 61 that support the secondary transfer belt 36 so as to be able to rotate around it. The secondary transfer unit 34 also includes an opposing roll 32B. The opposing roll 32B faces the secondary transfer roll 60 via the intermediate transfer belt 31 and the secondary transfer belt 36. The secondary transfer unit 34 also includes a contact roll 64 that supplies power to the opposing roll 32B by contacting it. Furthermore, the secondary transfer unit 34 includes a cleaning device 62 that removes toner from the surface of the secondary transfer belt 36. In the secondary transfer unit 34, the contact roll 64 applies a transfer bias between the opposing roll 32B and the secondary transfer roll 60. This creates a transfer electric field. This transfer electric field transfers the toner image superimposed on the intermediate transfer belt 31 to the paper P conveyed between the intermediate transfer belt 31 and the secondary transfer belt 36.

[0054] The secondary transfer belt 36 is endless and is wrapped around the secondary transfer roll 60 and the driven roll 61. The secondary transfer roll 60 is rotationally driven by a motor (not shown). The driven roll 61 moves in conjunction with the circumferential movement of the secondary transfer belt 36.

[0055] As an example, the secondary transfer belt 36 comprises a layer in which carbon is dispersed in an elastomer such as polyurethane, and a surface layer made of fluororesin or the like.

[0056] The secondary transfer roll 60 is positioned so as to sandwich the intermediate transfer belt 31 and the secondary transfer belt 36 between it and the opposing roll 32B. The secondary transfer belt 36 and the intermediate transfer belt 31 are in contact with a predetermined load. The area between the contacting secondary transfer belt 36 and the intermediate transfer belt 31 is defined as the secondary transfer position NT. Paper P is supplied to this secondary transfer position NT from the container 51 in a timely manner.

[0057] For example, the secondary transfer roll 60 is made of a foamed roll in which a conductive resin is dispersed. For example, the driven roll 61 is made of a metal roll.

[0058] For example, the opposing roll 32B has a configuration in which a conductive material such as carbon is dispersed in a foamed roll.

[0059] A variable power supply 68 is connected to the contact roll 64. The variable power supply 68 is a power supply capable of varying a constant DC voltage and constant current. Although not shown in the figure, the variable power supply 68 is equipped with a switching mechanism for switching and supplying a positive voltage and a negative voltage. The variable power supply 68 can switch between a positive voltage and a negative voltage using the switching mechanism and supply it to the contact roll 64. A current measuring element 69 and a voltage measuring element 70 are connected to the wiring 68A between the contact roll 64 and the variable power supply 68. The current measuring element 69 measures the current in the secondary transfer section 34. The voltage measuring element 70 measures the voltage in the secondary transfer section 34.

[0060] In the image forming apparatus 80A, a transfer bias is applied to the opposing roll 32B via the contact roll 64 by a variable power supply 68.

[0061] For example, when transferring the toner image on the surface of the intermediate transfer belt 31 to the paper P, a variable power supply 68 applies a negative voltage to the opposing roll 32B via the contact roll 64. This creates a potential difference between the opposing roll 32B and the secondary transfer roll 60. In other words, by applying a negative voltage to the opposing roll 32B, a secondary transfer voltage (positive voltage) with the opposite polarity to the toner is indirectly applied to the secondary transfer roll 60, which forms the opposing electrode of the opposing roll 32B. As a result, the toner image of the negative electrode is transferred from the intermediate transfer belt 31 to the paper P as it passes through the secondary transfer position NT.

[0062] In the secondary transfer section 34, a transfer bias is applied to the opposing roll 32B by constant current control or constant voltage control using a variable power supply 68. For example, the output of the transfer bias is determined by the temperature and humidity detected by the sensor 46 and the type of paper P. In addition, the output of the transfer bias is determined by the width of the paper P in a direction perpendicular to the transport direction.

[0063] When paper P does not pass through, a bias of the opposite polarity to that during transfer is applied to the opposing roll 32B by the variable power supply 68. For example, in the secondary transfer section 34, the load at the pressing point between the opposing roll 32B and the secondary transfer roll 60 is between 30N and 200N. The load at the pressing point is determined by the type of paper P and the temperature and humidity.

[0064] For example, when the toner on the intermediate transfer belt 31 is to be held on the intermediate transfer belt 31 as it passes through the secondary transfer position NT, a positive voltage is applied to the opposing roll 32B via the contact roll 64 by the variable power supply 68. This creates a potential difference between the opposing roll 32B and the secondary transfer roll 60. In other words, by applying a positive voltage to the opposing roll 32B, a non-transfer voltage (negative voltage) with the same polarity as the toner is indirectly applied to the secondary transfer roll 60, which forms the opposing electrode of the opposing roll 32B. As a result, the toner passing through the secondary transfer position NT is held on the intermediate transfer belt 31 by a repulsive force from the secondary transfer roll 60.

[0065] In the image forming apparatus 80A, a transfer bias is applied to the opposing roll 32B by constant current control using a variable power supply 68. When the image forming operation starts, the intermediate transfer belt 31 and the secondary transfer belt 36 move in a circular motion. Then, a standard current value corresponding to the process speed, which is the image forming speed, is applied to the contact roll 64. The current travels along the creepage surface of the opposing roll 32B, and the transfer bias is applied to the paper P via the intermediate transfer belt 31.

[0066] The voltage measuring element 70 measures the component voltage Vm applied to the component before the paper P passes through in the secondary transfer section 34. The voltage measuring element 70 also measures the paper voltage Vp, which is an example of the recording medium voltage division when the paper P passes through in the secondary transfer section 34.

[0067] The cleaning device 62 is a blade that contacts the secondary transfer belt 36 and removes toner adhering to the secondary transfer belt 36. For example, the blade that makes up the cleaning device 62 is made of polyurethane or the like.

[0068] (Fusing device 40) The fixing device 40 includes a heating roll 40A and a pressure roll 40B that is pressed against the heating roll 40A. The paper P onto which the toner image has been transferred passes through the nip between the heating roll 40A and the pressure roll 40B. This fixes the toner image to the paper P.

[0069] <Sensor 46> Sensor 46 detects temperature and humidity. The temperature and humidity information detected by sensor 46 is output to control device 10.

[0070] <Electrical configuration of the control device> As shown in Figure 2, the control device 10 includes a CPU (Central Processing Unit: processor) 11, a memory 15 as a temporary storage area, a non-volatile storage unit 13, an input unit 14, a media read / write (R / W) device 16, a communication interface (I / F) unit 18, and an external I / F unit 19. The CPU 11, memory 15, storage unit 13, input unit 14, media read / write device 16, communication I / F unit 18, and external I / F unit 19 are connected to each other via bus B1.

[0071] The CPU 11 controls the overall operation of the control unit 10.

[0072] The storage unit 13 is implemented by an HDD (Hard Disk Drive), SSD (Solid State Drive), flash memory, etc. The storage unit 13, as a storage medium, stores an information processing program 13A. The information processing program 13A is stored in the storage unit 13 when the recording medium 17 on which the information processing program 13A is written is set in the media read / write device 16, and the media read / write device 16 reads the information processing program 13A from the recording medium 17. The CPU 11 reads the information processing program 13A from the storage unit 13, loads it into memory 15, and sequentially executes the processes contained in the information processing program 13A. The storage unit 13 also stores a voltage information database 13B, which will be described later.

[0073] The input unit 14 is an interface that allows the user to input jobs to be executed by the image forming apparatus 80A. The input unit 14 includes a display unit and an operation unit.

[0074] The display unit is a display screen configured by combining, for example, a touch panel with a liquid crystal display or an organic EL display. Images and the like are displayed on the display unit in response to user touch operations or processing by the image forming apparatus 80A. The operation unit consists of operation keys, operation buttons, and a power button provided on the image forming apparatus 80A.

[0075] The user can specify job details or input job execution instructions to the image forming apparatus 80A by touching the display unit. Alternatively, user input operations may be performed via the control unit.

[0076] The media read / write device 16 reads information written to the recording medium 17 and writes information to the recording medium 17. The communication interface 18 is an interface for enabling communication between the control device and, for example, a server located outside the control device 10 or various terminals used by users. Communication standards such as Wi-Fi®, Bluetooth®, and LAN (Local Area Network) can be used in the communication interface 18.

[0077] <Functional configuration of the control device> Next, with reference to Figure 3, the functional configuration of the control device 10 according to this embodiment will be described. As shown in Figure 3, the control device 10 includes an acquisition unit 11A, a determination unit 11B, a setting unit 11C, a calculation unit 11D, and a control unit 11E. The CPU 11 of the control device 10 functions as the acquisition unit 11A, the determination unit 11B, the setting unit 11C, the calculation unit 11D, and the control unit 11E by executing the information processing program 13A.

[0078] (Acquisition Department) The acquisition unit 11A acquires job execution instructions from the user via the input unit 14. For example, the acquisition unit 11A acquires an instruction to transfer an image to an image recording medium (print execution instruction). If the acquisition unit 11A receives an execution instruction for a subsequent job while a job is being executed, the subsequent job is stored in the storage unit 13 as job waiting to be executed.

[0079] The acquisition unit 11A acquires the current value measured by the current measuring element 71 and the voltage value measured by the voltage measuring element 73 of the primary transfer unit 33. The acquisition unit 11A also acquires the current value measured by the current measuring element 69 of the secondary transfer unit 34. Furthermore, the acquisition unit 11A acquires the voltage value measured by the voltage measuring element 70 of the secondary transfer unit 34.

[0080] (Control Unit) The control unit 11E controls various functions provided in the image forming apparatus 80A, such as the image forming unit 12.

[0081] The control unit 11E controls the output of the primary transfer unit 33 to the variable power supply 72. Under the control of the control unit 11E, a positive primary transfer voltage is applied to the primary transfer roll 33A with constant current control. In this specification, the current that flows through the primary transfer unit 33 when transferring an image to the paper P is referred to as the "transfer primary current." The voltage applied to the primary transfer roll 33A when the transfer primary current flows through the primary transfer unit 33 is referred to as the "transfer primary voltage."

[0082] The control unit 11E controls the output of the secondary transfer unit 34 to the variable power supply 68. Under the control of the control unit 11E, a negative polarity secondary transfer voltage is applied to the opposing roll 32B with constant current control. Also, under the control of the control unit 11E, a positive polarity secondary transfer voltage is applied to the opposing roll 32B with constant current control.

[0083] When the control unit 11E transfers the toner image from the intermediate transfer belt 31 to the paper P, it applies a negative polarity secondary transfer voltage to the opposing roll 32B. In this specification, the current that flows through the secondary transfer unit 34 when transferring an image to the paper P is referred to as the "transfer secondary current." The voltage applied to the opposing roll 32B when the transfer secondary current flows through the secondary transfer unit 34 is referred to as the "transfer secondary voltage."

[0084] The control unit 11E applies a positive polarity secondary transfer voltage to the opposing roll 32B when removing toner adhering to the secondary transfer belt 36. The control unit 11E also applies a positive polarity secondary transfer voltage to the opposing roll 32B when calculating a correction coefficient (details described later) to correct the primary current during transfer.

[0085] The state in which voltages of the same polarity are applied to the primary transfer section 33 and the secondary transfer section 34 that are in contact with the intermediate transfer belt 31 is referred to as the "first state." The first state is, for example, a state in which a positive current is passed through the primary transfer section 33 and a positive current is passed through the secondary transfer section 34.

[0086] Furthermore, the state in which the primary transfer unit 33 is set to receive the same current as in the first state, and a voltage of opposite polarity is applied to the primary and secondary transfer units, is referred to as the "second state." The second state is, for example, a state in which a positive current flows through the primary transfer unit 33 and a negative current flows through the secondary transfer unit 34. Note that "the primary transfer unit 33 is set to receive the same current as in the first state" means that the current setting of the primary transfer unit 33 is maintained when transitioning from the first state to the second state.

[0087] Furthermore, the control unit 11E adjusts the "primary current during transfer". Specifically, the control unit 11E adjusts the output of the primary transfer unit 33 to the variable power supply 72 and supplies the "corrected primary current during transfer" to the primary transfer unit 33 using a "correction coefficient" which will be described later.

[0088] (Judgment Department) The determination unit 11B determines whether the voltage of the primary transfer unit 33 (i.e., the primary transfer voltage) acquired by the acquisition unit 11A is equal to or greater than a predetermined reference voltage when the control unit 11E supplies a "primary transfer current" to the primary transfer unit 33 and a "secondary transfer current" to the secondary transfer unit 34. The reference voltage is, for example, 1000[V]. This reference voltage can be set in advance and is stored in the voltage information database 13B.

[0089] Furthermore, when the control unit 11E flows the "transfer-time primary current" through the primary transfer unit 33 and the "transfer-time secondary current" through the secondary transfer unit 34, the determination unit 11B determines whether the difference between a predetermined "reference voltage" and the voltage of the primary transfer unit 33 acquired by the acquisition unit 11A (i.e., the transfer-time primary voltage) is below a threshold. For example, the threshold is 500[V]. This threshold can be set in advance and is stored in the voltage information database 13B.

[0090] (Calculation section) The calculation unit 11D calculates a correction coefficient based on the voltage measurement of the primary transfer unit 33 in the first state and the voltage measurement of the primary transfer unit 33 in the second state. The method for calculating the correction coefficient will be described later.

[0091] The calculation unit 11D calculates a correction coefficient based on the voltage measurement value of the primary transfer section 33 (primary transfer position T(K)) that is closest to the secondary transfer section 34 on the upstream side in the circumferential direction of the intermediate transfer belt 31.

[0092] <Types of methods for correcting the primary current during transfer> This section describes the types of methods for correcting the primary current during transfer.

[0093] (Case 1) • Initial state When a print job involving image transfer to paper P is input to the image forming apparatus 80A, the control unit 11E supplies a primary transfer current to the primary transfer unit 33. In the example shown in Case 1 of Figure 4, the primary transfer current is 10 μA. The control unit 11E also supplies a secondary transfer current to the secondary transfer unit 34. At this time, a positive voltage is applied to the primary transfer unit 33 and a negative voltage is applied to the secondary transfer unit 34. This state is referred to as the initial state.

[0094] Furthermore, the acquisition unit 11A acquires the primary voltage (transfer-time primary voltage) measured by the voltage measuring element 73 as needed. Also, the acquisition unit 11A acquires the secondary voltage (transfer-time secondary voltage) measured by the voltage measuring element 70 as needed.

[0095] In the example shown in Case 1 of Figure 4, if the predetermined reference voltage is 1000V, the initial primary voltage is 1400V, which is above the reference voltage. Thus, Case 1 is defined as the case where the voltage when the primary current is passed through the primary transfer unit 33 during transfer (primary voltage during transfer) is above the predetermined reference voltage. In the following explanation, the reference voltage will be set to 1000V.

[0096] • First state Next, the control unit 11E adjusts the current flowing through the secondary transfer unit 34. This causes the secondary transfer unit 34 to receive a current with the same polarity (positive polarity) as the primary transfer unit 33 and with the same voltage as the primary transfer unit 33. In this case, current interference between the primary transfer unit 33 and the secondary transfer unit 34 is less likely to occur compared to when these voltages are different. In the example shown in Case 1 of Figure 4, a current of 2000V, which is the same voltage as the primary transfer unit 33, is applied to the secondary transfer unit 34. Note that "equal voltage" does not need to be strictly identical and may include a setting error of about 10%.

[0097] • Second state Next, the control unit 11E adjusts the current flowing through the secondary transfer unit 34. This causes a current (transfer-time secondary current) to flow through the secondary transfer unit 34, which is a transfer-time secondary voltage with the opposite polarity (negative polarity) to the primary transfer unit 33. The primary transfer unit 33 is set to have the same current flowing through it as in the first state. At this time, the voltages in the primary transfer unit 33 and the secondary transfer unit 34 are different. As a result, current interference occurs between the primary transfer unit 33 and the secondary transfer unit 34.

[0098] In the example shown in Case 1 of Figure 4, current interference occurs when -3000V is applied to the secondary transfer section 34 as the secondary voltage during transfer. As a result, the voltage of the primary transfer section 33 becomes 1400V.

[0099] • Calculation of correction factor Next, the calculation unit 11D calculates a correction coefficient based on the voltage measurement value of the primary transfer unit 33 in the first state (2000V) and the voltage measurement value of the primary transfer unit 33 in the second state (1400V). Specifically, the voltage measurement value of the primary transfer unit 33 in the first state is divided by the voltage measurement value of the primary transfer unit 33 in the second state. This calculates the correction coefficient K1 as follows.

[0100] K1 = 2000 / 1400 = 1.42

[0101] • Adjustment of the primary current during transfer Next, the control unit 11E adjusts the primary current during transfer using the calculated correction coefficient. Specifically, it supplies a current (corrected primary current during transfer A12) obtained by multiplying the initial primary current setting value (initial current A11) by the correction coefficient K1 to the primary transfer unit 33.

[0102] A12=A11×K1=10μA×1.42=14.2μA

[0103] (Case 2) • Initial state In the example shown in Case 2 of Figure 4, the initial primary voltage is 400V, which is less than the reference voltage (1000V).

[0104] • First state The control unit 11E adjusts the current flowing through the secondary transfer unit 34. As a result, the secondary transfer unit 34 is supplied with the same polarity (positive polarity) as the primary transfer unit 33, and a reference voltage is applied to it.

[0105] In the example shown in Case 2 of Figure 4, a current that applies a reference voltage is passed through the secondary transfer unit 34. At this time, the voltage of the primary transfer unit 33 becomes, for example, 600V. In this case, the difference between the reference voltage (1000V) and the voltage of the primary transfer unit 33 is 400V. For example, let's say the threshold for the difference between the reference voltage and the voltage of the primary transfer unit is 500V. In this case, in Case 2, the difference between the reference voltage and the voltage of the primary transfer unit 33, which is 400V, is below the threshold.

[0106] Thus, in cases other than Case 1, when a current that applies a reference voltage is passed through the secondary transfer section 34 and a primary transfer current is passed through the primary transfer section, and the difference between the reference voltage and the voltage of the primary transfer section is less than or equal to a threshold, this is defined as Case 2.

[0107] • Second state Next, the control unit 11E adjusts the current flowing through the secondary transfer unit 34. This applies a secondary voltage during transfer to the secondary transfer unit 34, which is a voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. The primary transfer unit 33 is set to have the same current flowing through it as in the first state. At this time, the voltages in the primary transfer unit 33 and the secondary transfer unit 34 are different. As a result, current interference occurs between the primary transfer unit 33 and the secondary transfer unit 34.

[0108] In the example shown in Case 2 of Figure 4, current interference occurs when -3000V is applied to the secondary transfer section 34 as the secondary voltage during transfer. As a result, the voltage of the primary transfer section 33 becomes 400V.

[0109] • Calculation of correction factor Next, the calculation unit 11D calculates a correction coefficient based on the voltage measurement value of the primary transfer unit 33 in the first state (600V) and the voltage measurement value of the primary transfer unit 33 in the second state (400V). Specifically, the voltage measurement value of the primary transfer unit 33 in the first state is divided by the voltage measurement value of the primary transfer unit 33 in the second state. This calculates the correction coefficient K2 as follows.

[0110] K2 = 600 / 400 = 1.50

[0111] • Adjustment of the primary current during transfer Next, the control unit 11E adjusts the primary current during transfer using the calculated correction coefficient. Specifically, it supplies a current (corrected primary current during transfer A22) obtained by multiplying the initial primary current setting value (initial current A21) by the correction coefficient K2 to the primary transfer unit 33.

[0112] A22=A21×K2=10μA×1.50=15.0μA

[0113] (Case 3) • Initial state In the example shown in Case 3 of Figure 4, the initial primary voltage is 300V, which is less than the reference voltage (1000V).

[0114] • First state The control unit 11E adjusts the current flowing through the secondary transfer unit 34 to supply a current to the secondary transfer unit 34 that has the same polarity (positive polarity) as the primary transfer unit 33 and to which a reference voltage is applied.

[0115] In the example shown in Case 3 of Figure 4, a current that applies a reference voltage is passed through the secondary transfer unit 34. At this time, the voltage of the primary transfer unit 33 becomes, for example, 400V. In this case, the difference between the reference voltage (1000V) and the voltage of the primary transfer unit 33 is 600V. In this Case 3, the difference of 600V between the reference voltage and the voltage of the primary transfer unit 33 is greater than the threshold (500V).

[0116] Thus, in cases other than Case 1, when a current that applies a reference voltage is passed through the secondary transfer section 34 and a primary transfer current is passed through the primary transfer section, and the difference between the reference voltage and the voltage of the primary transfer section is greater than the threshold, these are designated as Case 3 or Case 4. The threshold can be predetermined.

[0117] Furthermore, Case 3 is defined as the case where the acquisition unit 11A accepts a subsequent job that involves transferring an image to paper P. Also, as will be described later, Case 4 is defined as the case where the acquisition unit 11A does not accept a subsequent job that involves transferring an image to paper P.

[0118] In Case 3, the control unit 11E adjusts the current flowing through the primary transfer unit 33 in the first state so that a current equal to the voltage of the secondary transfer unit 34 and corresponding to the reference voltage (1000V) flows through the primary transfer unit 33. For example, in the example shown in Case 3 of Figure 4, the current flowing through the primary transfer unit 33 is set to 20μA. In this case, current interference between the primary transfer unit 33 and the secondary transfer unit 34 is less likely to occur compared to the case where these voltages are different.

[0119] • Second state Next, the control unit 11E adjusts the current flowing through the secondary transfer unit 34. This applies a secondary voltage during transfer to the secondary transfer unit 34, which is a voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. The primary transfer unit 33 is set to have the same current flowing through it as in the first state after current adjustment. At this time, the voltages in the primary transfer unit 33 and the secondary transfer unit 34 are different. Therefore, current interference occurs between the primary transfer unit 33 and the secondary transfer unit 34.

[0120] In the example shown in Case 3 of Figure 4, current interference occurs when -3000V is applied to the secondary transfer section 34 as the secondary voltage during transfer. As a result, the voltage of the primary transfer section 33 becomes 700V.

[0121] • Calculation of correction factor Next, the calculation unit 11D calculates a correction coefficient based on the voltage measurement value of the primary transfer unit 33 in the first state (1000V) and the voltage measurement value of the primary transfer unit 33 in the second state (700V). Specifically, the voltage measurement value of the primary transfer unit 33 in the first state is divided by the voltage measurement value of the primary transfer unit 33 in the second state. This calculates the correction coefficient K3 as follows.

[0122] K3 = 1000 / 700 = 1.42

[0123] • Adjustment of the primary current during transfer Next, the control unit 11E adjusts the primary current during transfer using the calculated correction coefficient. Specifically, it supplies a current (corrected primary current during transfer A32) obtained by multiplying the initial primary current setting value (initial current A31) by the correction coefficient K3 to the primary transfer unit 33.

[0124] A32=A31×K3=10μA×1.42=14.2μA

[0125] (Case 4) • Initial state In the example shown in Case 4 of Figure 4, the initial primary voltage is 300V, which is less than the reference voltage (1000V).

[0126] • First state The control unit 11E adjusts the current flowing through the secondary transfer unit 34. This causes the secondary transfer unit 34 to receive a current with the same polarity (positive polarity) as the primary transfer unit 33, and to which a reference voltage is applied.

[0127] In the example shown in Case 4 of Figure 4, a current that applies a reference voltage is passed through the secondary transfer unit 34. At this time, the voltage of the primary transfer unit 33 becomes, for example, 400V. In this case, the difference between the reference voltage (1000V) and the voltage of the primary transfer unit 33 is 600V. In this Case 4, the difference of 600V between the reference voltage and the voltage of the primary transfer unit 33 is greater than the threshold (500V).

[0128] In Case 4, the control unit 11E, in the first state, adjusts the current flowing to the secondary transfer unit 34 so that a current equal to the voltage (400V) of the primary transfer unit 33 is applied to the secondary transfer unit 34. In this case, current interference is less likely to occur between the primary transfer unit 33 and the secondary transfer unit 34 compared to the case where these voltages are different.

[0129] • Second state Next, the control unit 11E adjusts the current flowing through the secondary transfer unit 34. This applies a secondary voltage during transfer to the secondary transfer unit 34, which is a voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. The primary transfer unit 33 is set to have the same current flowing through it as in the first state after current adjustment. At this time, the voltages in the primary transfer unit 33 and the secondary transfer unit 34 are different. Therefore, current interference occurs between the primary transfer unit 33 and the secondary transfer unit 34.

[0130] In the example shown in Case 4 of Figure 4, current interference occurs when -3000V is applied to the secondary transfer section 34 as the secondary voltage during transfer. As a result, the voltage of the primary transfer section 33 becomes 300V.

[0131] • Calculation of correction factor Next, the calculation unit 11D calculates a correction coefficient based on the voltage measurement value of the primary transfer unit 33 in the first state (400V) and the voltage measurement value of the primary transfer unit 33 in the second state (300V). Specifically, the voltage measurement value of the primary transfer unit 33 in the first state is divided by the voltage measurement value of the primary transfer unit 33 in the second state. This calculates the correction coefficient K2 as follows.

[0132] K4 = 400 / 300 = 1.33

[0133] ·cleaning In Case 4, after calculating the correction coefficient, the control unit 11E supplies a current to the secondary transfer unit 34 that provides a voltage of 1000V or higher than the reference voltage. Then, it controls the cleaning device 62 to remove the toner adhering to the secondary transfer belt 36 and clean it.

[0134] • Adjustment of the primary current during transfer Next, the control unit 11E adjusts the primary current during transfer using the calculated correction coefficient. Specifically, it supplies a current (corrected primary current during transfer A42) obtained by multiplying the initial primary current setting value (initial current A41) by the correction coefficient K4 to the primary transfer unit 33.

[0135] A42=A41×K4=10μA×1.33=13.3μA

[0136] (Common points for each case) In cases 1, 3, and 4 described above, in order to calculate the correction coefficient, in the first state, a current is passed through the primary transfer unit 33 and the secondary transfer unit 34 that is equal in voltage (2000V in case 1, 1000V in case 3, and 400V in case 4).

[0137] In cases 1, 2, and 4 described above, the primary transfer current (10 μA) before adjustment is passed through the primary transfer unit 33 via the first and second states in order to calculate the correction coefficient.

[0138] In cases 1 and 4 described above, in order to calculate the correction coefficient, in the first state, a current is passed through the secondary transfer unit 34 that is equal to the voltage applied to the primary transfer unit 33 (2000V in case 1, and 400V in case 4). In other words, the voltage applied to the secondary transfer unit 34 is made to match the voltage applied to the primary transfer unit 33.

[0139] In Case 3, in the first state, the voltage applied to the primary transfer unit 33 is made to match the voltage (1000V) applied to the secondary transfer unit 34. In Case 2, in the first state, the voltage applied to the primary transfer unit 33 and the voltage applied to the secondary transfer unit 34 are not made to match.

[0140] <Current adjustment process> In the image forming apparatus 80A, the CPU 11 of the control device 10 starts the "current adjustment process" shown in Figure 5 when it receives a job that involves transferring an image to paper P.

[0141] When the current adjustment process is executed, in step S102, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and supplies the primary transfer current to the primary transfer unit 33 and the secondary transfer current to the secondary transfer unit 34. At this time, the CPU 11 acquires the primary transfer voltage (positive polarity) and the secondary transfer voltage (negative polarity). After step S102, the process proceeds to step S110.

[0142] In step S110, the CPU 11 determines whether the primary voltage obtained in step S102 is equal to or greater than a predetermined reference voltage (e.g., 1000V). If the determination in step S110 is positive, the process proceeds to step S112 to start the control of Case 1 described above. On the other hand, if the determination in step S110 is negative, the process proceeds to step S120.

[0143] In step S112, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 so that a current with the same polarity (positive polarity) as the primary transfer unit 33 and the same voltage as the primary transfer unit 33 is applied to the secondary transfer unit 34. After step S112, the process proceeds to step S114.

[0144] In step S114, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 to supply a current (transfer-time secondary current) to the secondary transfer unit 34 that is the transfer-time secondary voltage, which is the voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. After step S114, the process proceeds to step S116.

[0145] In step S116, the CPU 11 calculates a correction coefficient K1 based on the voltage value of the primary transfer unit 33 in the first state obtained in step S112 and the voltage measurement value of the primary transfer unit 33 in the second state obtained in step S114. After step S116, the process proceeds to step S118.

[0146] In step S118, the CPU 11 adjusts the current supplied to the primary transfer unit 33 using the correction coefficient K1 calculated in step S116. Specifically, the CPU 11 supplies the primary current set value supplied in step S102 multiplied by the correction coefficient K1 to the primary transfer unit 33 as the primary current supplied during correction transfer. After step S118, the process proceeds to step S150.

[0147] In step S120, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 so that a current equal to a predetermined reference voltage is applied to the secondary transfer unit 34. After step S120, the process proceeds to step S122.

[0148] In step S122, the CPU 11 determines whether the difference between the reference voltage and the voltage of the primary transfer unit obtained in step S120 is less than or equal to a predetermined threshold (for example, 500V). If the determination in step S122 is positive, the process proceeds to step S124 to start the control of Case 2 described above. On the other hand, if the determination in step S122 is negative, the process proceeds to step S130.

[0149] In step S124, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 to supply a current (transfer-time secondary current) to the secondary transfer unit 34 that is the transfer-time secondary voltage, which is the voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. After step S124, the process proceeds to step S126.

[0150] In step S126, the CPU 11 calculates a correction coefficient K2 based on the voltage value of the primary transfer unit 33 in the first state obtained in step S120 and the voltage measurement value of the primary transfer unit 33 in the second state obtained in step S124. After step S126, the process proceeds to step S128.

[0151] In step S128, the CPU 11 adjusts the current supplied to the primary transfer unit 33 using the correction coefficient K2 calculated in step S126. Specifically, the current obtained by multiplying the primary current set value supplied in step S102 by the correction coefficient K2 is supplied to the primary transfer unit 33 as the primary current during correction transfer. After step S128, the process proceeds to step S150.

[0152] In step S130, the CPU 11 determines whether or not it has accepted a job that involves transferring an image to paper P. If the determination in step S130 is positive, the process proceeds to step S132 to start controlling case 3 as described above. On the other hand, if the determination in step S130 is negative, the process proceeds to step S142 to start controlling case 4 as described above.

[0153] In step S132, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing through the primary transfer unit 33 to supply a current (reference voltage) to the primary transfer unit 33 that is equal to the voltage supplied to the secondary transfer unit 34. After step S132, the process proceeds to step S134.

[0154] In step S134, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 to supply a current (transfer-time secondary current) to the secondary transfer unit 34 that is the transfer-time secondary voltage, which is the voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. After step S134, the process proceeds to step S136.

[0155] In step S136, the CPU 11 calculates a correction coefficient K3 based on the voltage value of the primary transfer unit 33 in the first state obtained in step S132 and the voltage measurement value of the primary transfer unit 33 in the second state obtained in step S134. After step S136, the process proceeds to step S138.

[0156] In step S138, the CPU 11 adjusts the current supplied to the primary transfer unit 33 using the correction coefficient K3 calculated in step S136. Specifically, the current obtained by multiplying the primary current set value supplied in step S102 by the correction coefficient K3 is supplied to the primary transfer unit 33 as the primary current during correction transfer. After step S138, the process proceeds to step S150.

[0157] In step S142, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 so that a current equal to the voltage applied to the primary transfer unit 33 flows through the secondary transfer unit 34. After step S142, the process proceeds to step S144.

[0158] In step S144, the CPU 11 acquires the voltages of the primary transfer unit 33 and the secondary transfer unit 34, and adjusts the current flowing to the secondary transfer unit 34 to supply a current (transfer-time secondary current) to the secondary transfer unit 34 that is the transfer-time secondary voltage, which is the voltage with the opposite polarity (negative polarity) to that of the primary transfer unit 33. After step S144, the process proceeds to step S146.

[0159] In step S146, the CPU 11 calculates a correction coefficient K4 based on the voltage value of the primary transfer unit 33 in the first state obtained in step S142 and the voltage measurement value of the primary transfer unit 33 in the second state obtained in step S144. After step S146, the process proceeds to step S147.

[0160] In step S147, the CPU 11 supplies a current to the secondary transfer unit 34 that is equal to or greater than the reference voltage, and controls the cleaning device 62 to clean the secondary transfer unit 34. After step S147, the process proceeds to step S148.

[0161] In step S148, the CPU 11 adjusts the current flowing to the primary transfer unit 33 using the correction coefficient K4 calculated in step S146. Specifically, the CPU 11 multiplies the primary current set in step S102 by the correction coefficient K4 and flows this current to the primary transfer unit 33 as the primary current during correction transfer. The CPU 11 also adjusts the current flowing to the secondary transfer unit 34 and flows the secondary current during transfer to the secondary transfer unit 34. After step S148, the process proceeds to step S150.

[0162] In step S150, the CPU 11 controls the image forming unit 12 and other components to execute the supported print job. The current adjustment process terminates when the print job is completed.

[0163] <Mechanism and Effects> In the above embodiment, a correction coefficient is calculated based on the voltage measurement value of the primary transfer section in both the first state, where a positive voltage is applied to the secondary transfer section, and the second state, where a negative voltage is applied. Then, using this correction coefficient, the primary transfer current flowing through the primary transfer section during image transfer to the image recording medium is adjusted.

[0164] This makes it possible to supplement the current flowing from the primary transfer unit 33 to the secondary transfer unit 34 via the intermediate transfer belt 31 during image transfer to the image recording medium.

[0165] In cases 1, 3, and 4 of the above embodiments, in the first state, a current is passed through which equal voltages are applied to the primary transfer unit 33 and the secondary transfer unit 34. Therefore, current interference is less likely to occur between the primary transfer unit 33 and the secondary transfer unit 34 in the first state. As a result, the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary transfer unit 33 and the secondary transfer unit 34 are different.

[0166] In cases 1, 2, and 4 of the above embodiments, the primary current during transfer is applied to the primary transfer unit 33 in the first state. Therefore, the correction coefficients K1, K2, and K4 are calculated based on the voltage when the primary current during transfer is applied. This results in higher accuracy of the correction coefficients compared to the case where a current different from the primary current during transfer is applied to the primary transfer unit 33 and the correction coefficients are calculated.

[0167] In cases 1 and 4 of the above embodiments, in the first state, the current flowing to the secondary transfer unit 34 is adjusted so that a current equal to the voltage applied to the primary transfer unit 33 is supplied to the secondary transfer unit 34. Therefore, current interference between the primary transfer unit 33 and the secondary transfer unit 34 is less likely to occur in the first state. As a result, the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary transfer unit 33 and the secondary transfer unit 34 are different.

[0168] In Case 1 of the above embodiment, the voltage when the primary current is passed through the primary transfer unit 33 during transfer is equal to or greater than a predetermined reference voltage. In the first state, a current equal to that applied to the primary transfer unit 33 is passed through the secondary transfer unit 34. That is, a voltage equal to or greater than the reference voltage is applied to the secondary transfer unit 34. This eliminates the need for cleaning the secondary transfer unit 34, which is necessary when the voltage applied to the secondary transfer unit 34 is less than the reference voltage.

[0169] Furthermore, in the first state, the primary transfer current is passed through the primary transfer unit 33. This results in higher accuracy of the correction coefficient compared to the case where a different current is passed through the primary transfer unit 33 to calculate the correction coefficient.

[0170] In Case 3 of the above embodiment, in the first state, a current equal to the voltage of the secondary transfer unit 34 and which is the reference voltage is applied is passed through the primary transfer unit 33.

[0171] Therefore, in the first state, current interference is less likely to occur between the primary transfer unit 33 and the secondary transfer unit 34. As a result, the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary transfer unit 33 and the secondary transfer unit 34 are different. In addition, cleaning of the secondary transfer unit 34, which is required when the voltage applied to the secondary transfer unit 34 is less than the reference voltage, becomes unnecessary.

[0172] In case 4 of the above embodiment, in the first state, a current equal to the voltage of the primary transfer unit 33, which is the reference voltage, is applied to the secondary transfer unit 34. Also in the first state, a primary transfer current is applied to the primary transfer unit 33.

[0173] Therefore, in the first state, current interference is less likely to occur between the primary transfer section 33 and the secondary transfer section 34. As a result, the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary transfer section 33 and the secondary transfer section 34 are different. Furthermore, the accuracy of the correction coefficient is higher compared to the case where a current different from the primary current during transfer is passed through the primary transfer section 33 and the correction coefficient is calculated.

[0174] Furthermore, Case 4 of the above embodiment is executed when no subsequent jobs involving image transfer to paper P have been accepted. In this way, if there are no instructions to execute multiple jobs involving image transfer to paper P, the secondary transfer unit can be cleaned even if a voltage lower than the reference voltage is applied to the secondary transfer unit 34 in the first state.

[0175] In Case 2 of the above embodiment, in the first state, a primary current is passed through the primary transfer unit 33, and a current is passed through the secondary transfer unit 34 to apply a reference voltage. Therefore, cleaning of the secondary transfer unit 34, which is required when the voltage applied to the secondary transfer unit 34 is less than the reference voltage, becomes unnecessary.

[0176] In the above embodiment, in the initial state prior to the first and second states, a primary current is passed through the primary transfer unit 33 to obtain the voltage of the primary transfer unit. This makes it possible to confirm the voltage applied to the primary transfer unit 33 when a primary current is passed through it.

[0177] In the above embodiment, a correction coefficient is determined based on the voltage measurement value of the primary transfer section 33 closest to the secondary transfer section 34 on the upstream side in the circumferential direction of the intermediate transfer belt 31. This makes it possible to compensate for the current flowing from the primary transfer section 33 closest to the secondary transfer section 34 to the secondary transfer section 34.

[0178] <Other Embodiments> In the above embodiment, in case 4, after calculating the correction coefficient K4, the secondary transfer unit 34 is cleaned (step S147). However, the embodiments of this disclosure are not limited thereto. The primary current may be adjusted without such a cleaning step.

[0179] Furthermore, in the above embodiment, control of case 3 is executed when a subsequent job involving image transfer is accepted. Also, control of case 4 is executed when a subsequent job involving image transfer is not accepted. However, the embodiments of this disclosure are not limited thereto.

[0180] The image forming apparatus 80A can be pre-configured to determine whether to execute control case 3 or control case 4 when the difference between the primary voltage during transfer and the reference voltage is greater than a threshold.

[0181] Furthermore, in the above embodiment, control in case 2 is executed when the difference between the primary voltage during transfer and the reference voltage is less than or equal to a threshold. Also, if the difference between the primary voltage during transfer and the reference voltage is greater than the threshold, either control in case 3 or case 4 is executed. However, the embodiments of this disclosure are not limited thereto.

[0182] The image forming apparatus 80A can be pre-set to determine whether to execute control case 2, control case 3, or control case 4 when the primary voltage during transfer is below the reference voltage. Furthermore, although the above embodiment assumes an apparatus that can handle multiple cases as shown in Figure 4, it is also possible to assume only some cases and perform only some of them. Similarly, it is possible to perform only some of the processes in the flowchart of Figure 5. For example, some or all of the confirmation results in each step such as step S110, step S122, and step S130 may be omitted. In particular, steps that can be anticipated in advance due to the characteristics of the apparatus may be omitted.

[0183] Furthermore, in the above embodiment, the primary voltage during transfer is obtained in the initial state prior to the first and second states. However, the embodiments of this disclosure are not limited to this. For example, the primary voltage during transfer may be set in advance and used as a known value.

[0184] Furthermore, in the above embodiment, the correction coefficient is calculated based on the voltage measurement value of the primary transfer section 33 closest to the secondary transfer section 34 on the upstream side in the circumferential direction of the intermediate transfer belt 31. However, the embodiments of this disclosure are not limited to this. For example, the correction coefficient may be calculated based on the voltage measurement value of a primary transfer section 33 other than the primary transfer section 33 closest to the secondary transfer section 34.

[0185] Furthermore, in the above embodiment, for example, the hardware structure of the processing unit that executes the acquisition unit 11A, determination unit 11B, setting unit 11C, calculation unit 11D, and control unit 11E can be any of the following types of processors. As mentioned above, these types of processors include a CPU, which is a general-purpose processor that executes software (programs) and functions as a processing unit, as well as programmable logic devices (PLDs), such as FPGAs (Field-Programmable Gate Arrays), which are processors whose circuit configuration can be changed after manufacturing, and dedicated electrical circuits, such as ASICs (Application Specific Integrated Circuits), which are processors with circuit configurations specifically designed to execute specific processes.

[0186] The processing unit may consist of one of these various processors, or it may consist of a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, or a combination of a CPU and an FPGA). Alternatively, the processing unit may consist of a single processor. Some or all of these processors may be configured on the cloud. At least each of the processes described in the above embodiments may be executed by a processor on the cloud.

[0187] Examples of configuring a processing unit with a single processor include, firstly, a configuration where one or more CPUs and software combine to form a single processor, as is common in client and server computers, and this processor functions as the processing unit. Secondly, a configuration using a processor that realizes the functions of the entire system, including the processing unit, on a single IC (Integrated Circuit) chip, as is common in System-on-a-Chip (SoC) systems. Thus, the processing unit is configured, in terms of hardware structure, using one or more of the above-mentioned types of processors.

[0188] Furthermore, the hardware structure of these various processors can more specifically utilize an electrical circuit (circuitry) that combines circuit elements such as semiconductor elements. Thus, this disclosure can be implemented in various forms.

[0189] (Note) (((1))) Equipped with at least one processor, The aforementioned processor, A correction coefficient is calculated based on the voltage measurement of the primary transfer section in a first state in which the same polarity voltage is applied to the primary transfer section and the secondary transfer section in contact with the intermediate transfer belt of the image forming apparatus, and the voltage measurement of the primary transfer section in a second state in which the same current as in the first state is applied to the primary transfer section and the primary transfer section and the secondary transfer section is subjected to voltages of opposite polarity. Using the correction coefficient, the primary current flowing to the primary transfer section during image transfer to the image recording medium is adjusted. Information processing system. (((2))) The aforementioned processor, In the first state, a current is passed through which an equal voltage is applied to the primary transfer unit and the secondary transfer unit. The information processing system described in (((1))). (((3))) The aforementioned processor, In the first state, the primary transfer current before adjustment is passed through the primary transfer unit. The information processing system described in (((1))) or (((2))). (((4))) The aforementioned processor, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. An information processing system described in any one of the items (((1))) to (((3))). (((5))) The aforementioned processor, If the voltage when the primary current during transfer is passed through the primary transfer section is equal to or greater than a predetermined reference voltage, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. An information processing system described in any one of the items (((1))) to (((4))). (((6))) The aforementioned processor, If the voltage when the primary current is passed through the primary transfer unit is less than a predetermined reference voltage, In the first state, the primary transfer current is passed through the primary transfer section, and the current to which the reference voltage is applied is passed through the secondary transfer section. The information processing system described in (((1))) or (((3))). (((7))) The aforementioned processor, If the voltage when the primary current is passed through the primary transfer unit is less than a predetermined reference voltage, In the first state, the current flowing through the primary transfer section is adjusted to apply the reference voltage to the primary transfer section, which is equal to the voltage applied to the secondary transfer section. The information processing system described in (((1))) or (((2))). (((8))) The aforementioned processor, If the voltage when the primary current is passed through the primary transfer unit is less than a predetermined reference voltage, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. After calculating the correction coefficient, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to or greater than the reference voltage to the secondary transfer section to clean it. An information processing system described in any one of the items (((1))) to (((4))). (((9))) The aforementioned processor, When accepting a subsequent job that involves transferring an image to the aforementioned image recording medium, In the first state, the current flowing through the primary transfer section is adjusted to apply the reference voltage to the primary transfer section, which is equal to the voltage applied to the secondary transfer section. If no subsequent jobs involving image transfer to the aforementioned image recording medium are accepted, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. After calculating the correction coefficient, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to or greater than the reference voltage to the secondary transfer section to clean it. The information processing system described in (((7))). (((10))) The aforementioned processor, When the difference between a predetermined reference voltage and the voltage when the primary current is passed through the primary transfer unit is greater than a threshold, In the first state, a current is passed through which an equal voltage is applied to the primary transfer unit and the secondary transfer unit. The information processing system described in (((2))). (((11))) The aforementioned processor, Before the first state and the second state, The primary current during transfer is passed through the primary transfer section, and the voltage of the primary transfer section is obtained. An information processing system described in any one of the items (((1))) to (((10))). (((12))) The aforementioned processor, When there are multiple primary transfer sections in contact with the intermediate transfer belt, the correction coefficient is calculated based on the voltage measurement value of the primary transfer section closest to the secondary transfer section on the upstream side in the circumferential direction of the intermediate transfer belt. An information processing system described in any one of the items (((1))) to (((11))). (((13))) A correction coefficient is calculated based on the voltage measurement of the primary transfer section in a first state in which the same polarity voltage is applied to the primary transfer section and the secondary transfer section in contact with the intermediate transfer belt of the image forming apparatus, and the voltage measurement of the primary transfer section in a second state in which the same current as in the first state is applied to the primary transfer section and the primary transfer section and the secondary transfer section are subjected to voltages of opposite polarity. The primary current supplied to the primary transfer unit during image transfer to the image recording medium is adjusted using the correction coefficient. An information processing program that is executed by a computer.

[0190] According to the information processing system (((1))) and the information processing program (((13)))), the current flowing from the primary transfer unit to the secondary transfer unit via the intermediate transfer belt during image transfer to the image recording medium can be supplemented. According to the information processing system (((2))), the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary and secondary transfer sections are different. According to the information processing system (((3))), the accuracy of the correction coefficient is higher compared to the case where a different current from the primary current during transfer is passed through the primary transfer section to calculate the correction coefficient. According to the information processing system (((4))), the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary and secondary transfer sections are different. According to the information processing system (((5))), cleaning of the secondary transfer section, which is required when the voltage applied to the secondary transfer section is less than the reference voltage, becomes unnecessary. According to the information processing system (((6))), the secondary transfer section can be cleaned using a reference voltage. According to the information processing system (((7))), cleaning of the secondary transfer section, which is required when the voltage applied to the secondary transfer section is less than the reference voltage, becomes unnecessary. According to the information processing system (((8))), the accuracy of the correction coefficient is higher compared to the case where a different current from the primary current during transfer is passed through the primary transfer section to calculate the correction coefficient. In addition, the secondary transfer section can be cleaned. According to the information processing system (((9))), the secondary transfer unit can be cleaned when there are no instructions to execute multiple jobs involving image transfer to an image recording medium. According to the information processing system (((10))), the accuracy of the correction coefficient is higher compared to the case where the voltages applied to the primary and secondary transfer sections are different. According to the information processing system (((11))), the voltage applied to the primary transfer section when the primary current is passed during transfer can be confirmed. According to the information processing system (((12))), it is possible to supplement the current flowing from the primary transfer unit, which is closest to the secondary transfer unit, to the secondary transfer unit. [Explanation of Symbols]

[0191] 11 CPU (Processor) 13A Information Processing Program 31 Intermediate transfer belt 80 Information Processing Systems 80A Image forming apparatus 33 Primary Transfer Section 34 Secondary transfer section P paper (image recording medium)

Claims

1. Equipped with at least one processor, The aforementioned processor, A correction coefficient is calculated based on the voltage measurement of the primary transfer section in a first state in which the same polarity voltage is applied to the primary transfer section and the secondary transfer section in contact with the intermediate transfer belt of the image forming apparatus, and the voltage measurement of the primary transfer section in a second state in which the same current as in the first state is applied to the primary transfer section and the primary transfer section and the secondary transfer section is subjected to voltages of opposite polarity. Using the correction coefficient, the primary current flowing to the primary transfer section during image transfer to the image recording medium is adjusted. Information processing system.

2. The aforementioned processor, In the first state, a current is passed through which an equal voltage is applied to the primary transfer unit and the secondary transfer unit. The information processing system according to claim 1.

3. The aforementioned processor, In the first state, the primary transfer current before adjustment is passed through the primary transfer unit. The information processing system according to claim 1.

4. The aforementioned processor, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. The information processing system according to claim 2.

5. The aforementioned processor, If the voltage when the primary current during transfer is passed through the primary transfer section is equal to or greater than a predetermined reference voltage, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. The information processing system according to claim 2.

6. The aforementioned processor, If the voltage when the primary current is passed through the primary transfer unit is less than a predetermined reference voltage, In the first state, the primary transfer current is passed through the primary transfer section, and the current to which the reference voltage is applied is passed through the secondary transfer section. The information processing system according to claim 1.

7. The aforementioned processor, If the voltage when the primary current is passed through the primary transfer unit is less than a predetermined reference voltage, In the first state, the current flowing through the primary transfer section is adjusted to apply the reference voltage to the primary transfer section, which is equal to the voltage applied to the secondary transfer section. The information processing system according to claim 2.

8. The aforementioned processor, If the voltage when the primary current is passed through the primary transfer unit is less than a predetermined reference voltage, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. After calculating the correction coefficient, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to or greater than the reference voltage to the secondary transfer section to clean it. The information processing system according to claim 2.

9. The aforementioned processor, When accepting a subsequent job that involves transferring an image to the aforementioned image recording medium, In the first state, the current flowing through the primary transfer section is adjusted to apply the reference voltage to the primary transfer section, which is equal to the voltage applied to the secondary transfer section. If no subsequent jobs involving image transfer to the aforementioned image recording medium are accepted, In the first state, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to that of the primary transfer section to the secondary transfer section. After calculating the correction coefficient, the current flowing through the secondary transfer section is adjusted to apply a voltage equal to or greater than the reference voltage to the secondary transfer section to clean it. The information processing system according to claim 7.

10. The aforementioned processor, When the difference between a predetermined reference voltage and the voltage when the primary current is passed through the primary transfer unit is greater than a threshold, In the first state, a current is passed through which an equal voltage is applied to the primary transfer unit and the secondary transfer unit. The information processing system according to claim 2.

11. The aforementioned processor, Before the first state and the second state, The primary current during transfer is passed through the primary transfer section, and the voltage of the primary transfer section is obtained. The information processing system according to claim 1.

12. The aforementioned processor, When there are multiple primary transfer sections in contact with the intermediate transfer belt, the correction coefficient is calculated based on the voltage measurement value of the primary transfer section closest to the secondary transfer section on the upstream side in the circumferential direction of the intermediate transfer belt. The information processing system according to claim 1.

13. A correction coefficient is calculated based on the voltage measurement of the primary transfer section in a first state in which the same polarity voltage is applied to the primary transfer section and the secondary transfer section in contact with the intermediate transfer belt of the image forming apparatus, and the voltage measurement of the primary transfer section in a second state in which the same current as in the first state is applied to the primary transfer section and the primary transfer section and the secondary transfer section are subjected to voltages of opposite polarity. The primary current supplied to the primary transfer unit during image transfer to the image recording medium is adjusted using the correction coefficient. An information processing program that is executed by a computer.

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