Image forming apparatus, image forming system, image forming method, and program

Abstract

To prevent reduction in productivity.SOLUTION: An image forming apparatus 100 comprises: an image forming unit that forms an image on a recording medium; a temperature sensor that detects the temperature inside the apparatus; a counter that counts an integrated value of output results from the image forming unit; and a control unit that controls the operation of the image forming unit. The control unit can execute first control of continuing the operation while reducing the output from the image forming unit when the temperature inside the apparatus is equal to or more than a first reference temperature, and second control of stopping the output from the image forming unit and executing an adjustment operation when the integrated value is equal to or more than a first reference integrated value. When the temperature inside the apparatus is equal to or more than a second reference temperature lower than the first reference temperature, and when the integrated value is equal to or more than a second reference integrated value lower than the first reference integrated value, the control unit executes the second control.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to an image forming apparatus, an image forming system, an image forming method, and a program.

Background Art

[0002] In an image forming apparatus, it is known to integrate a weighted count value weighted based on print mode information included in each job as an index value (see, for example, Patent Document 1). In the image forming apparatus described in Patent Document 1, when the integrated value obtained by integration becomes equal to or greater than a preset determination threshold value, the density of the image is adjusted.

[0003] Also, in an image forming apparatus, it is known to stop a printing operation when the temperature inside the apparatus exceeds a preset determination threshold value (see, for example, Patent Document 2).

Summary of the Invention

Problems to be Solved by the Invention

[0004] In an image forming apparatus according to the related art, when the temperature of a fixing device or the temperature inside the apparatus becomes equal to or higher than a predetermined temperature, there is an apparatus that controls the temperature so as not to cause overheating by reducing the productivity of the apparatus. Further, in an image forming apparatus according to the related art, when the cumulative number of printed sheets becomes equal to or greater than a predetermined number, process control for controlling image forming conditions is executed. In such an image forming apparatus, productivity may decrease by changing the image forming conditions.

[0005] An object of the present disclosure is to provide an image forming apparatus capable of suppressing a decrease in productivity.

Means for Solving the Problems

[0006] An image forming apparatus according to an aspect of the present disclosure includes: an image forming unit that forms an image on a recording medium; a temperature sensor that detects the temperature inside the apparatus; A counter that counts the integrated value of the output result by the image forming unit, and a control unit that controls the operation of the image forming unit. The control unit performs a first control to continue operation while reducing the output by the image forming unit when the temperature inside the machine is equal to or higher than a first reference temperature, and is capable of performing a second control to stop the output by the image forming unit and execute an adjustment operation when the integrated value is equal to or higher than a first reference integrated value. The control unit performs the second control when the temperature inside the machine is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value.

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide an image forming apparatus capable of suppressing a decrease in productivity.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiment for Carrying out the Invention

[0009] Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings. In the present specification and drawings, substantially the same components may be denoted by the same reference numerals, and redundant descriptions may be omitted.

[0010] In the present specification, image formation, printing, printing, or recording are all synonymous.

[0011] [Image Forming Apparatus 100 According to the Embodiment] FIG. 1 is a schematic view showing an example of an image forming apparatus 100 according to the embodiment. The image forming apparatus 100 may be an electrophotographic tandem type color image forming apparatus. The image forming apparatus 100 includes a paper feeding unit 10, a conveyance mechanism 20, an image forming unit 30, a fixing unit 40, and a paper discharging unit 60.

[0012] The image forming unit 30 includes one intermediate transfer belt 35, a plurality of photoreceptor drums 34K, 34C, 34M, 34Y arranged to face the intermediate transfer belt 35, and a transfer unit 32. The image forming apparatus 100 can form a full-color image on a recording medium PP supplied by the paper feeding unit 10 and the conveyance mechanism 20 by the image forming unit 30, convey the recording medium PP on which the full-color image is formed by the conveyance mechanism 20, and discharge it to the paper discharging unit 60.

[0013] [Recording Medium PP] The recording medium PP may be, for example, paper or a transparent film. The paper may be, for example, white paper or black paper. The color of the paper may be other colors, for example, yellow, pink, or blue. The recording medium PP may be other than paper and film.

[0014] [Paper Feeding Unit 10] The paper feeding unit 10 has a plurality of trays for holding the recording medium PP. The plurality of trays hold different types of recording media PP. Different types of recording media PP include those with different materials or different colors. The paper feeding unit 10 holds, for example, a recording medium PP that is white paper. The paper feeding unit 10B holds, for example, a recording medium PP that is black paper. The image forming apparatus 100 may be provided with a paper feeding unit 10 that holds three or more types of recording media PP respectively, or may be provided with a paper feeding unit 10 that holds one type of recording medium PP.

[0015] [Transport mechanism 20] The transport mechanism 20 is a transport mechanism that supplies the recording medium PP held in the paper feeding unit 10 to the transfer unit 32. The transport mechanism 20 includes a transport mechanism that transports the recording medium PP that has passed through the transfer unit 32 of the image forming unit 30. The recording medium PP that has passed through the transfer unit 32 is sent to the subsequent paper discharge unit 60. The transport mechanism 20 includes a pair of transport rollers 22 for transporting the recording medium PP. The transport mechanism 20 includes a guide for guiding the transport of the recording medium PP.

[0016] [Image forming unit 30] The image forming unit 30 includes a transfer unit 32, photosensitive drums 34K, 34C, 34M, 34Y, an intermediate transfer belt 35, and a secondary transfer roller 36. The intermediate transfer belt 35 is an endless belt on which an intermediate transfer image is formed. The intermediate transfer belt 35 moves in a circular motion. The photosensitive drums 34K, 34C, 34M, 34Y are arranged side by side in order from the upstream side in the moving direction of the intermediate transfer belt 35.

[0017] The photosensitive drums 34K, 34C, 34M, 34Y carry toner images on their surfaces. The intermediate transfer belt 35 is arranged facing the plurality of photosensitive drums 34K, 34C, 34M, 34Y. The transfer unit 32 transfers the toner image to the recording medium PP.

[0018] The photoreceptor drum 34K transfers the black toner image to the intermediate transfer belt 35, forming a black toner image on the surface of the intermediate transfer belt 35. The photoreceptor drum 34C transfers the cyan toner image to the intermediate transfer belt 35, forming a cyan toner image on the surface of the intermediate transfer belt 35. The photoreceptor drum 34M transfers the magenta toner image to the intermediate transfer belt 35, forming a magenta toner image on the surface of the intermediate transfer belt 35. The photoreceptor drum 34Y transfers the yellow toner image to the intermediate transfer belt 35, forming a yellow toner image on the surface of the intermediate transfer belt 35.

[0019] The image forming unit 30 may have a photoreceptor drum 34S that transfers a special toner image to the intermediate transfer belt 35. The photoreceptor drum 34S transfers the special toner to the intermediate transfer belt 35, forming a special toner image on the surface of the intermediate transfer belt 35. Examples of the special toner include white, gold, silver, fluorescent color, fluorescent coloring, clear, and intermediate colors.

[0020] The secondary transfer roller 36 transfers the toner image formed on the intermediate transfer belt 35 to the surface of the recording medium PP.

[0021] [Fixing unit 40] The fixing unit 40 is provided downstream of the image forming unit 30. The fixing unit 40 includes a fixing roller and a heater. The fixing unit 40 fixes the toner image transferred to the recording medium PP onto the surface of the recording medium PP. Thereby, an image is formed on the surface of the recording medium PP. The fixing unit 40 fixes the toner image to the recording medium PP by heating and pressing the recording medium PP onto which the toner image has been transferred. The heater may be, for example, a halogen heater. The heater is built into the fixing roller.

[0022] [Paper discharge unit 60] The paper discharge unit 60 includes a paper discharge tray where the printed recording medium PP is discharged. The printed recording medium PP is discharged to the paper discharge unit 60.

[0023] [Hardware configuration of the image forming apparatus 100] Next, the hardware configuration of the image forming apparatus 100 will be described with reference to FIG. 2. FIG. 2 is a block diagram showing an example of the hardware configuration of the image forming apparatus 100 according to the embodiment. The image forming apparatus 100 includes a control device 200 having a control unit 210.

[0024] A printer driver 110 is connected to the control unit 210. The printer driver 110 generates print data. The printer driver 110 may generate print data in a host device such as an information processing terminal such as a PC (Personal Computer), an image reading device such as an image scanner, or an imaging device such as a digital camera. The printer driver 110 generates dot pattern data for image output in the image forming apparatus 100.

[0025] [Control Unit 210] The control unit 210 includes a CPU (Center Processing Unit) 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, and an NVRAM (Non Volatile Random Access Memory) 204.

[0026] The CPU 201 is an arithmetic unit and controls the operations of the entire image forming apparatus 100. The CPU 201 controls the conveyance operation of the recording medium PP and the printing operation by the image forming unit 30. The ROM 202 is a read-only non-volatile storage medium. The ROM 202 stores programs such as firmware. The RAM 203 is a volatile storage medium capable of high-speed reading and writing of information. The RAM 203 is used as a work area when the CPU 201 processes information.

[0027] The NVRAM 204 is a non-volatile storage medium capable of reading and writing information. The NVRAM 204 stores an OS (Operating System), various control programs, application programs, and the like.

[0028] The program stored in the storage unit is read into the RAM 203, and the CPU 201 performs calculations according to the program loaded into the RAM 203, thereby configuring the software control unit. The storage unit includes a ROM 202 and an NVRAM 204. The storage unit may include a storage medium such as an optical disk.

[0029] A functional block that realizes the functions of the image forming apparatus 100 is configured by a combination of hardware and the software control unit. The CPU 201 and the RAM 203 function as various control units as shown in FIG. 3. The various control units will be described later.

[0030] [Operation panel 111] The image forming apparatus 100 includes an operation panel 111. The operation panel 111 is connected to the control unit 210. The operation panel 111 is an input unit that can be operated by a user for input. The operation panel 111 may be, for example, a liquid crystal panel. The user can operate the operation panel 111 to change the setting of the printing conditions. Also, the user can operate the operation panel 111 to change the setting of various conditions.

[0031] The user can operate the operation panel 111 to input information regarding the recording medium PP. The user can operate the operation panel 111 to input, for example, whether the recording medium PP is white paper or not. The information input via the operation panel 111 is transmitted to the control unit 210. The operation panel 111 may be a display unit and an input unit of a terminal (PC) connected to the control unit 210.

[0032] [Temperature sensor 160] The image forming apparatus 100 includes a temperature sensor 160. The temperature sensor 160 detects the temperature inside the machine. The temperature inside the machine may be the temperature inside the housing of the image forming apparatus 100. The temperature inside the machine may be, for example, the temperature near the heater of the fixing unit 40. The image forming apparatus 100 may include a plurality of temperature sensors 160 that detect the temperature at different locations.

[0033] The image forming apparatus 100 may include other sensors other than the temperature sensor 160. The image forming apparatus 100 may include a sensor that detects the color and density of an image formed on the recording medium PP. The image forming apparatus 100 may include, for example, a camera that images the printing surface of the recording medium PP as other sensors. The printing surface is the surface on which the image is formed.

[0034] [Functional Configuration] Next, with reference to FIG. 3, the functional configuration of the control unit 210 will be described. FIG. 3 is a functional block diagram of the control unit 210 of the image forming apparatus 100 according to the embodiment. The CPU 201 shown in FIG. 2 realizes each function of the data input unit 231, the data expansion unit 232, the temperature detection unit 233, the integrated value counting unit 234, the operation mode setting unit 235, the operation condition setting unit 236, the determination unit 237, and the storage unit 250 shown in FIG. 3 by executing a program stored in a storage unit such as the ROM 202. Note that external devices and sensors connected to the control unit 210 may execute a part of these functions.

[0035] [Data Input Unit 231] The data input unit 231 receives various data. The data input unit 231 receives print data from, for example, a client PC.

[0036] [Data Expansion Unit 232] The data expansion unit 232 converts, for example, print data in a file format into PDL in the same manner as a printer driver. That is, in PDL, the position, size, color, font, etc. of each character are specified, and the position of the image in the printing area of the recording medium PP is specified.

[0037] [Data Generation Unit 258 for Multiple Prints] The data generation unit 258 for multiple prints creates data for multiple prints on the same surface of the recording medium PP. The data generation unit 258 for multiple prints generates data for multiple prints based on the medium information. Details will be described later.

[0038] [Temperature Detection Unit 233] The temperature detection unit 233 detects the internal temperature of the apparatus based on the detection result by the temperature sensor 160. The control unit 210 can detect the internal temperature of the image forming apparatus 100.

[0039] [Integration value counting unit 234] The integration value counting unit 234 counts the integration value of the output result by the image forming unit 30. The integration value counting unit 234 can calculate the number of sheets of the printed recording medium PP as the integration value. The integration value counting unit 234 may calculate the number of printed sheets based on the data of the print job and use it as the integration value. The integration value counting unit 234 may calculate the number of printed sheets based on the data stored in the storage unit 250. The number of printed sheets of the recording medium PP is an example of the output result.

[0040] [Operation mode setting unit 235] The operation mode setting unit 235 can set the operation mode in the image forming apparatus 100. Examples of the operation mode may include a quality priority mode, a cost priority mode, and a productivity priority mode. The quality priority mode is selected when emphasizing print quality. The cost priority mode is selected when emphasizing reduction of printing costs. In the cost priority mode, for example, toner consumption can be suppressed. The productivity priority mode is selected, for example, when emphasizing print speed. The user can select the operation mode by, for example, operating and inputting using the operation panel 111. The operation mode setting unit 235 can set the selected operation mode as the operation mode of the image forming apparatus 100.

[0041] [Operation condition setting unit 236] The operation condition setting unit 236 can set the operation conditions in the image forming apparatus 100. The operation condition setting unit 236 can change the operation conditions according to the operation mode. The operation condition setting unit can set the operation conditions, for example, according to the internal temperature detected by the temperature sensor 160. Examples of the operation conditions include print density, print speed, and the like.

[0042] [Judgment unit 237] The determination unit 237 can determine, for example, whether or not the in-machine temperature is equal to or higher than a first reference temperature (determination threshold value). The determination unit 237 can determine, for example, whether or not the in-machine temperature is equal to or higher than a second reference temperature (determination threshold value). The second reference temperature may be a value lower than the first reference temperature.

[0043] The determination unit 237 can determine whether or not the integrated value of the output result by the image forming unit is equal to or higher than a first reference integrated value (determination threshold value). The determination unit 237 can determine whether or not the integrated value of the output result by the image forming unit is equal to or higher than a second reference integrated value (determination threshold value). The second reference integrated value may be a value lower than the first reference integrated value.

[0044] The determination unit 237 may change various determination threshold values according to the operation mode. The determination unit 237 may change at least one of the second reference temperature and the second reference integrated value according to the operation mode.

[0045] The control unit 210 can control the operation of the image forming unit 30. When the in-machine temperature is equal to or higher than the first reference temperature, the control unit 210 can execute a first control to continue the operation while reducing the output by the image forming unit 30. When the in-machine temperature is equal to or higher than the first reference temperature, the control unit 210 can reduce the output by the image forming unit 30 as compared with the case where the in-machine temperature is lower than the first reference temperature. Reducing the output by the image forming unit 30 may be, for example, reducing the number of printed sheets per unit time.

[0046] When the integrated value is equal to or higher than the first reference integrated value, the control unit 210 can execute a second control to stop the output by the image forming unit 30 and execute an adjustment operation. Stopping the output by the image forming unit 30 may be not executing the printing operation. When the number of printed sheets becomes equal to or higher than the first reference integrated value, the control unit 210 can stop the printing. The printing may be stopped and a maintenance operation in the image forming apparatus 100 may be executed. The adjustment operation may be a maintenance operation.

[0047] When the internal temperature is equal to or higher than a second reference temperature that is lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value that is lower than the first reference integrated value, the control unit 210 can execute second control. When the internal temperature is equal to or higher than the second reference temperature and the integrated value is equal to or higher than the second reference integrated value, the control unit 210 can execute an adjustment operation. The image forming apparatus 100 can execute an adjustment operation when the integrated value reaches a second integrated value before the internal temperature reaches the first reference temperature.

[0048] The adjustment operation may include a plurality of types of adjustment operations. The adjustment operation may include a first adjustment operation and a second adjustment operation having a longer working time than the adjustment operation.

[0049] When the internal temperature is equal to or higher than a third reference temperature (determination threshold value) that is higher than the second reference temperature and lower than the first reference temperature and the integrated value is equal to or higher than the second reference integrated value, the control unit 210 may execute the second adjustment operation.

[0050] When the internal temperature is lower than the third reference temperature and the integrated value is equal to or higher than the second reference integrated value, the control unit 210 may execute the first adjustment operation.

[0051] The control unit 210 can change the third reference temperature. The control unit 210 can change the third reference temperature according to, for example, the operation mode. When the third reference temperature is low, the control unit 210 can shorten the working time in the second adjustment operation as compared with the case where the third reference temperature is high.

[0052] The control unit 210 can execute a normal operation mode that is a normal operation mode and a productivity priority operation mode that has higher productivity than the normal operation mode. When the productivity priority operation mode is being executed, the control unit 210 can enable the execution of the second control, and when the normal operation mode is being executed, the control unit 210 can disable the execution of the second control.

[0053] [Storage unit 250] The storage unit 250 stores various types of information. The storage unit 250 stores data regarding the determination threshold value. The storage unit 250 stores the determination threshold value regarding the internal temperature. The storage unit 250 stores the determination threshold value regarding the integrated value.

[0054] [Control Process; First Embodiment] Next, with reference to FIGS. 4 and 5, the procedure of the control process executed in the image forming apparatus 100 will be described. FIG. 4 is a flowchart showing the procedure of the control process (productivity down operation determination) according to the first embodiment. FIG. 5 is a flowchart showing the procedure of the control process (adjustment execution determination) according to the first embodiment. The control unit 210 can execute the control processes of FIGS. 4 and 5 by each functional component shown in FIG. 3. The control processes shown in FIGS. 4 and 5 can be executed in parallel.

[0055] The control process shown in FIG. 4 is a process for determining whether to execute a productivity down operation. The control unit 210 of the image forming apparatus 100 determines whether the internal temperature is equal to or higher than the first reference temperature T1 (step S11). If the internal temperature is equal to or higher than the first reference temperature T1, the control unit 210 executes the process of step S12. If the internal temperature is lower than the first reference temperature T1, the control unit 210 ends the process here.

[0056] In step S12, the control unit 210 executes a productivity down operation. The control unit 210 reduces the output by the image forming unit 30. The control unit 210 may, for example, reduce the printing speed. After executing the process in step S12, the control unit 210 ends the process here.

[0057] The control process shown in FIG. 5 is a process for determining whether to execute an adjustment operation. The adjustment operation includes stopping the output by the image forming unit 30. First, the control unit 210 determines whether the internal temperature is equal to or higher than the second reference temperature T2 (step S21). If the internal temperature is equal to or higher than the second reference temperature T2, the control unit 210 executes the process of step S22. If the internal temperature is lower than the second reference temperature T2, the control unit 210 executes the process of step S23.

[0058] In step S22, the control unit 210 determines whether the integrated value, which is the number of printed sheets, is equal to or greater than the second reference integrated value M2. If the integrated value is equal to or greater than the second reference integrated value M2, the control unit 210 executes the process of step S24. If the integrated value is less than the second reference integrated value M2, the control unit 210 executes the process of step S23.

[0059] In step S23, the control unit 210 determines whether the integrated value, which is the number of printed sheets, is equal to or greater than the first reference integrated value M1. If the integrated value is equal to or greater than the first reference integrated value M1, the control unit 210 executes the process of step S24. If the integrated value is less than the first reference integrated value M1, the control unit 210 ends the process here.

[0060] In step S24, the control unit 210 executes an adjustment operation. In step S24, the control unit 210 executes an adjustment operation to stop the output by the image forming unit 30. Here, an adjustment operation for preventing image quality degradation is executed. The adjustment operation may include a maintenance operation in the image forming unit 30. In step S24, the integrated value, which is the number of printed sheets, is reset to 0. After executing the process in step S24, the control unit 210 ends the process here.

[0061] [Control Process; Second Embodiment] FIG. 6 is a flowchart showing the procedure of the control process (adjustment execution determination) according to the second embodiment. The control process shown in FIG. 6 is a process for determining whether to execute an adjustment operation. In the control process shown in FIG. 6, it is possible to determine which adjustment operation among a plurality of adjustment operations (first adjustment operation, second adjustment operation, third adjustment operation) is to be executed. In FIG. 6, the same step numbers are assigned to the processes similar to the flowchart shown in FIG. 5. Also, similar explanations may be omitted.

[0062] First, the control unit 210 determines whether the temperature inside the machine is equal to or higher than the second reference temperature T2 (step S21). The same process as the above-described process is executed.

[0063] In step S22, the control unit 210 determines whether the integrated value, which is the number of printed sheets, is equal to or greater than the second reference integrated value M2. If the integrated value is equal to or greater than the second reference integrated value M2, the control unit 210 executes the process of step S25. If the integrated value is less than the second reference integrated value M2, the control unit 210 executes the process of step S23.

[0064] In step S23, the control unit 210 determines whether the integrated value, which is the number of printed sheets, is equal to or greater than the first reference integrated value M1. If the integrated value is equal to or greater than the first reference integrated value M1, the control unit 210 executes the process of step S24. If the integrated value is less than the first reference integrated value M1, the control unit 210 ends the process here.

[0065] In step S24, the control unit 210 executes the first adjustment operation. In step S24, the control unit 210 executes the first adjustment operation to stop the output by the image forming unit 30. After executing the process in step S24, the control unit 210 ends the process here.

[0066] In step S25, the control unit 210 determines whether the integrated value, which is the number of printed sheets, is equal to or greater than the third reference integrated value M3. If the integrated value is equal to or greater than the third reference integrated value M3, the control unit 210 executes the process of step S27. If the integrated value is less than the third reference integrated value M3, the control unit 210 executes the process of step S26.

[0067] In step S26, the control unit 210 executes the second adjustment operation. In step S26, the control unit 210 executes the second adjustment operation to stop the output by the image forming unit 30. The second adjustment operation is a simple adjustment operation with a shorter execution time compared to the third adjustment operation. After executing the process in step S26, the control unit 210 ends the process here.

[0068] In step S27, the control unit 210 executes a third adjustment operation. In step S27, the control unit 210 executes a third adjustment operation to stop the output by the image forming unit 30. The third adjustment operation includes a complex adjustment operation with a longer execution time compared to the second adjustment operation. After executing the process in step S27, the control unit 210 ends the process here.

[0069] [Control Process; Third Embodiment] FIG. 7 is a flowchart showing the procedure of the control process (adjustment execution determination) according to the third embodiment. The control process shown in FIG. 7 is a process for determining whether to execute an adjustment operation. In the control process shown in FIG. 7, before the process of step S21, a process for determining the operation mode (step S31) is executed. In FIG. 7, the same step numbers are assigned to the processes similar to the flowchart shown in FIG. 5. Also, the same explanations may be omitted.

[0070] First, the control unit 210 determines whether it is in the productivity priority mode (step S31). If the current operation mode of the image forming apparatus 100 is the productivity priority mode, the control unit 210 executes the process of step S23. If the current operation mode is not the productivity priority mode, the control unit 210 executes the process of step S21. Steps S21 to S24 are as described above and are the same as the flowchart shown in FIG. 5. According to the flowchart shown in FIG. 7, it is possible to select whether to execute steps S21 and S22 according to the operation mode.

[0071] [Change in Operating Status] FIG. 8 is a diagram showing the change in the operating status of the image forming apparatus 100. FIG. 8(a) is a diagram showing the change in the operating status of the image forming apparatus 100 according to the embodiment. In FIG. 8, the horizontal axis represents the passage of time.

[0072] As shown in FIG. 8(a), at time t10, the image forming apparatus 100 is performing printing at, for example, the normal printing speed. The control unit 210 of the image forming apparatus 100 is executing the processes shown in FIGS. 4 and 5 above. At time t11, the internal temperature has reached the second reference temperature T2 (T2 < T1). The control unit 210 does not execute CPM down at time t11. "CPM down" is an example of the first control that continues the printing operation while executing temperature control to suppress overheating of the internal temperature. The first control does not include the second control that executes an adjustment operation to stop the output by the image forming unit 30. In the image forming apparatus 100, by executing CPM down, a productivity down operation in the image forming unit 30 is performed.

[0073] At time t12, the number of printed sheets reaches the second reference integrated value M2 (M2 < M1). The control unit 210 executes adjustment (pro-con). Adjustment (pro-con) includes image density adjustment (process control) and includes operations to prevent image quality degradation. The adjustment is an example of the second control. The control unit 210 may execute the adjustment by stopping the operation of the image forming unit 30. In the image forming apparatus 100, by executing the adjustment, the temperature of the fixing unit 40 can be lowered. In the image forming apparatus 100, by executing the adjustment, the internal temperature can be lowered. In the image forming apparatus 100, since the internal temperature can be lowered, the downtime due to CPM down is less likely to occur.

[0074] At time t13, the adjustment ends. In the image forming apparatus 100, from time t13 to time t15, no downtime due to CPM down occurs. In the image forming apparatus 100, from time t13 to time t15, printing can be performed at the normal printing speed. Therefore, the productivity in the image forming apparatus 100 does not decrease.

[0075] [Changes in the operating status of the image forming apparatus according to the comparative example] FIG. 8(b) is a diagram showing changes in the operating status of the image forming apparatus according to the comparative example. As shown in FIG. 8(b), at time t20, the image forming apparatus 100 is performing printing at, for example, the normal printing speed.

[0076] At time t21, the internal temperature reaches the first reference temperature T1. The control unit executes CPM down. The image forming apparatus according to the comparative example performs a productivity down operation. In the image forming apparatus according to the comparative example, CPM down is executed from time t21 to time t23.

[0077] At time t23, the number of printed sheets reaches the first reference integrated value M1. The control unit executes adjustment. The control unit may execute the adjustment by stopping the operation of the image forming unit.

[0078] At time t24, the adjustment ends. In the image forming apparatus according to the comparative example, printing can be performed at the normal printing speed from time t24 to time t25.

[0079] In the image forming apparatus according to the comparative example, downtime due to CPM down occurs from time t21 to time t23. In the image forming apparatus according to the comparative example, adjustment is executed from time t23 to time t24. On the other hand, in the image forming apparatus 100 according to the embodiment, adjustment is executed from time t12 to time t13. In the image forming apparatus 100, during the period from time t10 to time t12 and the period from time t13 to time t15, printing can be performed at the normal printing speed. In the image forming apparatus 100 according to the embodiment, compared with the image forming apparatus according to the comparative example, the period during which printing can be performed at the normal printing speed is longer. The image forming apparatus 100 has a shorter time with low productivity (time with CPM down) compared with the image forming apparatus according to the comparative example. In the image forming apparatus 100, a decrease in productivity can be suppressed.

[0080] During the execution of the adjustment operation, printing is not possible, so the temperature inside the machine drops. By the temperature inside the machine dropping, it is possible to suppress the occurrence of a productivity decrease due to CPM down. For example, in the image forming apparatus according to the comparative example, there is a possibility that CPM down for preventing an overrise in the temperature inside the machine may occur at a timing when the adjustment operation occurs immediately, and there was a possibility that productivity would decrease in an unnecessary situation. In the image forming apparatus 100 according to the embodiment, since it is possible to suppress the occurrence of CPM down immediately before the adjustment operation, it is possible to suppress a decrease in productivity.

[0081] [Operation and effect of the image forming apparatus 100 according to the embodiment] The image forming apparatus 100 according to the embodiment includes an image forming unit 30 that forms an image on a recording medium PP, a temperature sensor 160 that detects the temperature inside the machine, an integrated value counting unit (counter) 234 that counts the integrated value of the output results by the image forming unit 30, and a control unit 210 that controls the operation of the image forming unit 30. When the temperature inside the machine is equal to or higher than the first reference temperature T1, the control unit 210 can execute a first control (CPM down) that continues the operation while reducing the output by the image forming unit 30, and when the integrated value is equal to or higher than the first reference integrated value M1, a second control that stops the output by the image forming unit 30 and executes an adjustment operation. The control unit 210 executes the second control when the temperature inside the machine is equal to or higher than a second reference temperature T2 that is lower than the first reference temperature T1 and the integrated value is equal to or higher than a second reference integrated value M2 that is lower than the first reference integrated value M1.

[0082] According to the image forming apparatus 100 according to the embodiment, by executing the second control before the temperature inside the machine reaches the first reference temperature T1, it is possible to delay the execution of the first control (CPM down). Therefore, in the image forming apparatus 100, it is possible to suppress a decrease in productivity.

[0083] In the image forming apparatus 100, the control unit 210 can execute a plurality of different operation modes, and at least one of the second reference temperature T2 and the second reference integrated value M2 can be changed according to the operation mode. In such an image forming apparatus 100, the timing of executing the second control can be changed according to the operation mode.

[0084] In the image forming apparatus 100, the adjustment operation includes a first adjustment operation and a second adjustment operation having a longer working time than the first adjustment operation. When the temperature inside the machine is equal to or higher than a third reference temperature T3, which is higher than the second reference temperature T2 and lower than the first reference temperature T1, and the integrated value is equal to or higher than the second reference integrated value M2, the control unit may execute the second adjustment operation. When the temperature inside the machine is lower than the third reference temperature T3 and the integrated value is equal to or higher than the second reference integrated value M2, the first adjustment operation may be executed. In such an image forming apparatus 100, the working time of the adjustment operation can be changed according to the temperature inside the machine. According to the image forming apparatus 100, the content of the adjustment operation may be changed according to the temperature inside the machine.

[0085] In the image forming apparatus 100, the control unit 210 can change the third reference temperature T3. When the third reference temperature T3 is low, the working time in the second adjustment operation may be shorter than when the third reference temperature T3 is high. In the image forming apparatus 100, by changing the third reference temperature T3, the working time in the second adjustment operation can be adjusted.

[0086] In the image forming apparatus 100, the control unit 210 can execute a normal operation mode, which is a normal operation mode, and a productivity priority operation mode having higher productivity than the normal operation mode. When the productivity priority operation mode is being executed, the second control can be executed. When the normal operation mode is being executed, the execution of the second control can be made impossible. In such an image forming apparatus 100, in the productivity priority operation mode, by executing the second control, the productivity can be improved compared to the normal operation mode.

[0087] Also, in the image forming apparatus 100, the image forming unit 30 includes a photosensitive drum 34K, 34C, 34M, 34Y that carries a toner image on its surface, an intermediate transfer belt 35 that is disposed facing the photosensitive drums 34K, 34C, 34M, 34Y and to which the toner image is transferred, and a transfer unit 32 that transfers the toner image to a recording medium PP. In this image forming apparatus 100, the toner image carried on the surfaces of the photosensitive drums 34K, 34C, 34M, 34Y can be transferred to the recording medium PP via the intermediate transfer belt 35 and the transfer unit 32.

[0088] Note that the above-described embodiments are presented as examples and are not intended to limit the scope of the present invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. Also, the embodiments and modifications of the embodiments are included in the scope and gist of the invention and are included in the invention described in the claims and its equivalent scope.

[0089] [Processing Circuit] Each function of the above-described embodiments can be realized by one or a plurality of processing circuits. Here, the "processing circuit" in this specification includes a processor programmed to execute each function by software like a processor implemented by an electronic circuit, an ASIC (Application Specific Integrated Circuit) designed to execute each function described above, a DSP (digital signal processor), an FPGA (field programmable gate array), and devices such as conventional circuit modules.

[0090] In the above-described embodiment, a multicolor image forming apparatus 100 having photosensitive drums for each of a plurality of colors is exemplified, but the image forming apparatus may perform monochromatic image formation with a single photosensitive drum.

[0091] The image forming apparatus may be a liquid ejection apparatus. The liquid ejection apparatus includes a discharge head that discharges liquid. In the liquid ejection apparatus, the image forming unit may include a liquid discharge unit that discharges liquid onto a recording medium PP, and a fixing unit that fixes the liquid discharged onto the recording medium PP. In the liquid ejection apparatus, second control for executing a maintenance operation as an adjustment operation may be performed. Examples of the maintenance operation include a wiping operation for cleaning the nozzle surface of the discharge head, and a dummy discharge operation for discharging liquid that does not contribute to image formation. The maintenance operation includes an operation for maintaining the liquid discharge operation by the discharge head and an operation for restoring the liquid discharge operation.

[0092] One aspect of the present invention may be as follows.

[0093] <1> An image forming unit that forms an image on a recording medium; A temperature sensor that detects the temperature inside the machine; A counter that counts an integrated value of the output result by the image forming unit; A control unit that controls the operation of the image forming unit, The control unit, When the temperature inside the machine is equal to or higher than a first reference temperature, first control for continuing the operation while reducing the output by the image forming unit; When the integrated value is equal to or higher than a first reference integrated value, second control for stopping the output by the image forming unit and executing an adjustment operation, The control unit, An image forming apparatus that executes the second control when the temperature inside the machine is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value. <2> The control unit, The image forming apparatus according to <1> above, which is capable of executing a plurality of different operation modes and changing at least one of the second reference temperature and the second reference integrated value according to the operation mode. <3> The adjustment operation includes a first adjustment operation and a second adjustment operation having a longer working time than the first adjustment operation. The control unit When the internal temperature is equal to or higher than a third reference temperature that is higher than the second reference temperature and lower than the first reference temperature, and the integrated value is equal to or higher than the second reference integrated value, the second adjustment operation is executed. The image forming apparatus according to <1> or <2> above, wherein when the internal temperature is lower than the third reference temperature and the integrated value is equal to or higher than the second reference integrated value, the first adjustment operation is executed. <4> The control unit can change the third reference temperature. The image forming apparatus according to <3> above, wherein when the third reference temperature is low, the working time in the second adjustment operation is shorter than when the third reference temperature is high. <5> The control unit A normal operation mode which is a normal operation mode, and A productivity priority operation mode having higher productivity than the normal operation mode, and can execute the two. When the productivity priority operation mode is being executed, the second control can be executed. The image forming apparatus according to any one of <1> to <4> above, wherein when the normal operation mode is being executed, the execution of the second control is made impossible. <6> The image forming unit A photosensitive drum that carries a toner image on its surface, An intermediate transfer belt that is disposed facing the photosensitive drum and to which the toner image is transferred, A transfer unit that transfers the toner image to the recording medium, and the image forming apparatus according to any one of <1> to <5> above. <7> An image forming unit that forms an image on a recording medium, A temperature sensor that detects the internal temperature, A counter that counts an integrated value of the output result by the image forming unit, A control unit that controls the operation of the image forming unit, and is provided with The control unit when the internal temperature is equal to or higher than a first reference temperature, perform a first control to continue the operation while reducing the output by the image forming unit; when the integrated value is equal to or higher than a first reference integrated value, perform a second control to stop the output by the image forming unit and execute an adjustment operation, and is capable of executing the second control; The control unit An image forming system that executes the second control when the internal temperature is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value. <8> An image forming step of forming an image on a recording medium using an image forming unit; A temperature detection step of detecting the internal temperature; A counting step of counting an integrated value of output results by the image forming unit; And a control step of controlling the operation of the image forming unit, The control step when the internal temperature is equal to or higher than a first reference temperature, a first control step of continuing the operation while reducing the output by the image forming unit; when the integrated value is equal to or higher than a first reference integrated value, a second control step of stopping the output by the image forming unit and executing an adjustment operation, and including the second control step; In the control step An image forming method that executes the second control step when the internal temperature is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value. <9> A program for causing a computer to execute a control process for forming an image on a recording medium using an image forming unit, A process of executing an image forming step of forming an image on the recording medium using the image forming unit; A process of executing a temperature detection step of detecting the internal temperature; A process of executing a counting step of counting an integrated value of output results by the image forming unit; Causing the computer to execute a process of causing the control step for controlling the operation of the image forming unit to be executed; The control step includes: A first control step of continuing the operation while reducing the output by the image forming unit when the temperature inside the machine is equal to or higher than a first reference temperature; A second control step of stopping the output by the image forming unit and executing an adjustment operation when the integrated value is equal to or higher than a first reference integrated value; In the control step, A program for executing the second control step when the temperature inside the machine is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value.

Explanation of Signs

[0094] 100 Image forming apparatus 30 Image forming unit 160 Temperature sensor 200 Control device 210 Control unit 234 Integrated value counting unit (counter)

Prior Art Documents

Patent Documents

[0095]

Patent Document 1

Patent Document 2

Claims

1. An image forming unit that forms an image on a recording medium, A temperature sensor that detects the internal temperature of the machine, A counter that counts the integrated value of the output result by the image forming unit, A control unit that controls the operation of the image forming unit, and includes, The control unit, When the internal temperature is equal to or higher than the first reference temperature, a first control for continuing the operation while reducing the output by the image forming unit, When the integrated value is equal to or higher than the first reference integrated value, a second control for stopping the output by the image forming unit and executing an adjustment operation can be executed, The control unit, An image forming apparatus that executes the second control when the internal temperature is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value.

2. The control unit, Can execute a plurality of different operation modes, and according to the operation mode, at least one of the second reference temperature and the second reference integrated value is changed. The image forming apparatus according to claim 1.

3. The adjustment operation includes a first adjustment operation and a second adjustment operation having a longer working time than the first adjustment operation, When the control unit, The internal temperature is equal to or higher than a third reference temperature higher than the second reference temperature and lower than the first reference temperature, and the integrated value is equal to or higher than the second reference integrated value, the second adjustment operation is executed, The image forming apparatus according to claim 1, wherein when the internal temperature is lower than the third reference temperature and the integrated value is equal to or higher than the second reference integrated value, the first adjustment operation is executed.

4. The control unit can change the third reference temperature, When the third reference temperature is low, the working time in the second adjustment operation is shorter than when the third reference temperature is high. The image forming apparatus according to claim 3.

5. The control unit, A normal operation mode that is a normal operation mode, A productivity priority operation mode having higher productivity than the normal operation mode can be executed, When the productivity priority operation mode is being executed, the second control can be executed, The image forming apparatus according to claim 1, wherein when the normal operation mode is being executed, the execution of the second control is impossible.

6. The image forming unit, A photosensitive drum that carries a toner image on its surface, An intermediate transfer belt that is arranged facing the photosensitive drum and to which the toner image is transferred, An image forming apparatus according to claim 1, including a transfer unit that transfers the toner image to the recording medium.

7. An image forming unit that forms an image on a recording medium, A temperature sensor that detects the internal temperature, A counter that counts the integrated value of the output results by the image forming unit, A control unit that controls the operation of the image forming unit, and includes, The control unit, When the internal temperature is equal to or higher than a first reference temperature, a first control for continuing operation while reducing the output by the image forming unit, When the integrated value is equal to or higher than a first reference integrated value, a second control for stopping the output by the image forming unit and executing an adjustment operation, and can execute, The control unit, An image forming system that executes the second control when the internal temperature is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value.

8. An image forming step of forming an image on a recording medium using an image forming unit, A temperature detection step of detecting the internal temperature, A counting step of counting the integrated value of the output results by the image forming unit, A control step of controlling the operation of the image forming unit, and includes, The control step, When the internal temperature is equal to or higher than a first reference temperature, a first control step for continuing operation while reducing the output by the image forming unit, When the integrated value is equal to or higher than a first reference integrated value, a second control step for stopping the output by the image forming unit and executing an adjustment operation, and includes, In the control step, An image forming method that executes the second control step when the internal temperature is equal to or higher than a second reference temperature lower than the first reference temperature and the integrated value is equal to or higher than a second reference integrated value lower than the first reference integrated value.

9. A program that causes a computer to execute control processing for forming an image on a recording medium using an image forming unit, A process for executing an image forming step of forming an image on the recording medium using the image forming unit, A process for executing a temperature detection step of detecting the internal temperature, A process for executing a counting step of counting the integrated value of the output results by the image forming unit, A process for executing a control step of controlling the operation of the image forming unit is caused to be executed by the computer, The control step, When the internal temperature is equal to or higher than a first reference temperature, a first control step for continuing operation while reducing the output by the image forming unit, When the integrated value is equal to or higher than a first reference integrated value, a second control step for stopping the output by the image forming unit and executing an adjustment operation, and includes, In the control step, A program that executes the second control step when the in-aircraft temperature is equal to or higher than a second reference temperature that is lower than the first reference temperature, and when the integrated value is equal to or higher than a second reference integrated value that is lower than the first reference integrated value.

Images