JP5849833B2 - Image processing device - Google Patents

Description

  The present invention relates to an image processing apparatus, and more particularly to an image processing apparatus that executes predetermined image processing.

  As an invention related to a conventional general image processing apparatus, for example, an image processing apparatus described in Patent Document 1 is known. The image processing apparatus has a power saving mode such as a sleep mode and a ready mode. The power consumption in the sleep mode is smaller than the power consumption in the ready mode. When the image processing apparatus finishes a job such as printing or copying, the mode of the image processing apparatus shifts to the sleep mode. Then, when a predetermined time elapses from the ready mode, the mode of the image processing apparatus shifts to the sleep mode.

  The image processing apparatus configured as described above stores the time and time when shifting to the sleep mode and the time and time when shifting to the ready mode. The image processing apparatus changes the setting for a predetermined time based on these times to reduce the power consumption.

  However, in the image processing apparatus described in Patent Document 1, there is a possibility that the waiting time from execution of each mode to execution of a job such as printing or copying becomes long. More specifically, the waiting time until the job is executed in the sleep mode is longer than the waiting time until the job is executed in the ready mode. Therefore, if the predetermined time is set short to reduce the power consumption, the frequency of transition to the sleep mode increases. As a result, the standby time becomes long.

JP 2010-41529 A

  Accordingly, an object of the present invention is to provide an image processing apparatus capable of reducing power consumption and suppressing an increase in standby time until job execution.

  An image processing apparatus according to an aspect of the present invention includes: an execution unit that executes a job for predetermined image processing; and a waiting time required to execute a job in a non-job period in which the execution unit does not perform a job. A power saving unit that shifts the state of the execution unit to a plurality of types of power saving modes that are different and have different power consumption amounts, and an acquisition unit that acquires the first power consumption amount of the non-job period in a first predetermined period And counting means for counting the number of transitions to each power saving mode in the first predetermined period, and based on the power consumption of each power saving mode and the number of transitions to each power saving mode, The plurality of patterns are arranged so that the second power consumption amount in the non-job period in the second predetermined period having the same length as the predetermined period is smaller than the first power consumption amount by a reduction amount. Generating means for generating the number of transitions to each power saving mode in a predetermined period of 2; and waiting for the plurality of patterns based on the number of transitions to the power saving mode of the plurality of patterns and the waiting time of each power saving mode And a calculating means for calculating the total sum of time.

  According to the present invention, it is possible to reduce power consumption and to suppress an increase in waiting time until job execution.

1 is a diagram illustrating an overall configuration of an image forming apparatus. 3 is a block diagram illustrating a power supply configuration of the image forming apparatus. FIG. It is the graph which showed the target value of power consumption and power consumption in each weekend. It is the flowchart which showed the operation | movement which CPU performs. It is the flowchart which showed the operation | movement which CPU performs. It is the flowchart which showed the operation | movement which CPU performs. It is the flowchart which showed the operation | movement which CPU performs. It is the flowchart which showed the operation | movement which CPU performs. It is the flowchart which showed the operation | movement which CPU performs. It is the flowchart which showed the operation | movement which CPU performs.

  An image forming apparatus according to an embodiment of an image processing apparatus according to the present invention will be described below.

(Overall configuration of image forming apparatus)
Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of the image forming apparatus 1.

  The image forming apparatus 1 is an electrophotographic color printer, and synthesizes and prints toner images of four colors (Y: yellow, M: magenta, C: cyan, K: black) on a so-called tandem system. . The image forming apparatus 1 has a function of forming an image on a sheet based on image data read by a scanner. As shown in FIG. 1, the image forming apparatus 1 has a printing unit 2, a sheet feeding unit 15, a timing roller pair 19, a fixing unit. The apparatus 20 includes a paper discharge roller pair 21 and a paper discharge tray 23.

  The paper supply unit 15 serves to supply paper one by one and includes a paper tray 16 and a paper supply roller 17. A plurality of sheets in a state before printing are stacked on the sheet tray 16. The paper feed roller 17 takes out the paper placed on the paper tray 16 one by one.

  The timing roller pair 19 conveys the sheet while adjusting the timing so that the toner image is secondarily transferred in the printing unit 2 to the sheet conveyed by the paper feed roller 17.

  The printing unit 2 forms a toner image on the paper supplied from the paper supply unit 15, and the optical scanning device 6, the transfer unit 8 (8Y, 8M, 8C, 8K), the intermediate transfer belt 11, the driving roller 12, and the driven unit. It includes a roller 13, a secondary transfer roller 14, and an image forming unit 22 (22Y, 22M, 22C, 22K). The image forming unit 22 (22Y, 22M, 22C, 22K) includes a photosensitive drum 4 (4Y, 4M, 4C, 4K), a charger 5 (5Y, 5M, 5C, 5K), and a developing device 7 (7Y, 7K). 7M, 7C, 7K) and cleaner 9 (9Y, 9M, 9C, 9K).

  The photosensitive drum 4 (4Y, 4M, 4C, 4K) has a cylindrical shape, and is rotated clockwise in FIG. The charger 5 (5Y, 5M, 5C, 5K) charges the peripheral surface of the photosensitive drum 4 (4Y, 4M, 4C, 4K). The optical scanning device 6 scans the beam B (BY, BM, BC, BK) on the peripheral surface of the photosensitive drum 4 (4Y, 4M, 4C, 4K). Thereby, an electrostatic latent image is formed on the peripheral surface of the photosensitive drum 4 (4Y, 4M, 4C, 4K).

  The developing device 7 (7Y, 7M, 7C, 7K) develops a toner image based on the electrostatic latent image on the photosensitive drum 4 (4Y, 4M, 4C, 4K).

  The transfer belt 11 is stretched between the driving roller 12 and the driven roller 13. The transfer unit 8 is disposed so as to face the inner peripheral surface of the intermediate transfer belt 11 and plays a role of primary transfer of the toner image formed on the photosensitive drum 4 to the intermediate transfer belt 11. The cleaner 9 collects the toner remaining on the peripheral surface of the photosensitive drum 4 after the primary transfer. The driving roller 12 is rotated by an intermediate transfer belt driving unit (not shown in FIG. 1), thereby driving the intermediate transfer belt 11 in the direction of arrow α. As a result, the intermediate transfer belt 11 conveys the toner image to the secondary transfer roller 14.

  The secondary transfer roller 14 faces the intermediate transfer belt 11 and has a drum shape. The secondary transfer roller 14 secondarily transfers the toner image carried by the intermediate transfer belt 11 to a sheet passing between the secondary transfer roller 14 and the intermediate transfer belt 11 by applying a transfer voltage.

  The sheet on which the toner image is secondarily transferred is conveyed to the fixing device 20. The fixing device 20 fixes the toner image on the paper by performing heat treatment and pressure treatment on the paper. The paper discharge roller pair 21 discharges the paper conveyed from the fixing device 20 to the paper discharge tray 23. Printed paper is placed on the paper discharge tray 23.

(Power supply configuration of image forming apparatus)
Next, the power supply configuration of the image forming apparatus 1 will be described with reference to the drawings. FIG. 2 is a block diagram illustrating a power supply configuration of the image forming apparatus 1.

  The image forming apparatus 1 further includes a CPU 60, a RAM 62, a control board 63, an operation unit 64, a low voltage power supply 66, and a plug 70.

  The CPU 60 is a control unit that controls the entire image forming apparatus 1, and is mounted on the control board 63. The RAM 62 is a storage unit that stores predetermined information, and is mounted on the control board 63. The operation unit 64 is an input unit that receives input from the user and a display unit that displays information to the user, and is configured by a touch panel, for example.

  The plug 70 is inserted into an outlet and is supplied with 100V AC power from the outlet.

  The low-voltage power supply 66 is a power supply device that drops the AC power supplied from the plug 70 to a voltage suitable for the operation of the printing unit 2 and the paper feeding unit 15. On the other hand, the fixing device 20 operates by an AC voltage supplied from the plug 70.

  During the non-job period when the print job is not performed, there are four types of power saving modes, namely, standby 1 mode, standby 2 mode, low power mode, and sleep mode, in the operation state of the fixing device 20 and the low voltage power supply 66. The standby 1 mode is a power saving mode in which power is supplied to the fixing device 20 and the low voltage power supply 66 so that a print job can be immediately executed. The standby 2 mode is a power saving mode in which the temperature of the fixing device 20 is set lower than that in the standby 1 mode and power consumption is lower than that in the standby 1 mode. However, the time taken to execute the print job in the standby 2 mode is longer than the time taken to execute the print job in the standby 1 mode.

  The low power mode is a power saving mode that consumes less power than the standby 2 mode. The power supplied to the fixing device 20 and the low voltage power supply 66 in the low power mode is smaller than the power supplied to the fixing device 20 and the low voltage power supply 66 in the standby 2 mode. For this reason, the time taken to execute the print job in the low power mode is longer than the time taken to execute the print job in the standby 2 mode.

  The sleep mode is a power saving mode that consumes less power than the low power mode. The power supplied to the fixing device 20 and the low voltage power source 66 in the sleep mode is smaller than the power supplied to the fixing device 20 and the low voltage power source 66 in the low power mode. For this reason, the time taken to execute the print job in the sleep mode is longer than the time taken to execute the print job in the low power mode.

  As described above, in the standby 1 mode, the standby 2 mode, the low power mode, and the sleep mode, the standby time required for executing a job is different and the power consumption is different. Table 1 is a table showing power consumption and standby time in each mode. The power consumption amount in Table 1 is an average value of the power amount consumed when shifting to each mode once. The RAM 62 stores the table in Table 1.

  As the non-job period elapses, the CPU 60 shifts the operation states of the fixing device 20 and the low-voltage power supply 66 in the order of standby 1 mode, standby 2 mode, low power mode, and sleep mode.

  Note that when executing the print job in the standby 2 mode, the low power mode, or the sleep mode, the CPU 60 executes the print job after shifting to the warm-up mode. On the other hand, when executing the print job in the standby 1 mode, the CPU 60 executes the print job without shifting to the warm-up mode. In the warm-up mode, the fixing device 20 is heated.

  Further, the CPU 60 counts the number of transitions to each power saving mode in one week. The RAM 62 stores the number of transitions to each power saving mode in one week as a mode distribution. Table 2 is a table showing the mode distribution. In Table 2, the number of transitions to the standby mode is the sum of the number of transitions to the standby 1 mode and the number of transitions to the standby 2 mode.

  Table 2 also records a power consumption amount Sn in the nth week (n is an integer of 1 to 5) and a standby time TWn that is the sum of the standby times in the nth week. Calculation of the power consumption amount Sn and the standby time TWn will be described later.

(Operation of image forming apparatus)
The operation of the image forming apparatus 1 configured as described above will be described below with reference to the drawings. FIG. 3 is a graph showing the power consumption and the target value of power consumption for each weekend.

  First, the user inputs a target value X using the operation unit 64 of the image forming apparatus 1. The target value X is a target value of the power consumption during the non-job period for one month. Here, the target value X is 76.5 kW · h as shown in FIG.

  Next, the image forming apparatus 1 performs a normal operation for one week. The CPU 60 counts the number of transitions to each power saving mode in one week and generates a mode distribution. A specific example of mode distribution generation will be described below using a table. Table 3 is a table showing an example of power consumption and standby time in each power saving mode. Table 4 is a table showing an example of the mode distribution at the end of the first week.

  Table 3 indicates that the power consumption amount Wst in the standby 1 mode is 200 W · h. It also means that the standby time twst in the standby 1 mode is 0 seconds. The same applies to the standby 2 mode, the low power mode, and the sleep mode.

  In Table 4, it means that the number of times Tst of transition to the standby mode is 70 times, the low power mode Tlp is 20 times, and the sleep mode Tsl is 10 times in the first week. In the first week, the number of transitions to the standby mode means the number of transitions to the standby 1 mode. In the second week and thereafter, since the transition is made to the standby 2 mode instead of the standby 1 mode, the number of transitions to the standby mode means the number of transitions to the standby 2 mode.

  In Table 4, the power consumption S1 is 16100 W · h. The power consumption S1 is obtained by substituting the values in Tables 3 and 4 into the following formula (1).

S1 = Tst · Wst + Tlp · Wlp + Tsl · Wsl (1)

  In Table 4, the standby time TW1 is 550 s. The standby time TW1 is obtained by substituting the values in Tables 3 and 4 into the following formula (2).

TW1 = Tst · twst + Tlp · twlp + Tsl · twsl (2)

  Next, the CPU 60 determines a reduction amount Y based on the target value X. The reduction amount Y is the power consumption that should be reduced from the power consumption of this week per week in the next week. Specifically, the reduction amount Y at the end of the first week is obtained by the following equation (3).

Y = (5 · S1-X) / 4 (3)

  The reduction amount Y is obtained as 1000 W · h by substituting X = 76500 and S1 = 16100 into the equation (3).

  Next, based on the power consumption amount Wst−ΔWst, Wlp, Wsl of each power saving mode and the number of times Tst, Tlp, Tsl of transition to each power saving mode, the CPU 60 consumes power in the non-job period in the second week. The number of transition times Tst, Tlp, Tsl to the power saving mode in the second week of the plurality of patterns is generated so that S2 is smaller than the power consumption S1 in the first week by the reduction amount Y.

  Specifically, the CPU 60 changes the mode distribution so that the power consumption amount S2 of the second week is reduced by the reduction amount Y from the first power consumption amount S1. As shown in Table 4, the CPU 60 generates a sleep mode distribution, a low power pattern distribution, and a standby mode distribution. The mode distribution of the sleep pattern is a mode distribution in which the number of transitions to the sleep mode and the number of transitions to the low power mode and the standby mode are decreased in the first week distribution mode. The mode distribution of the low power pattern is a mode distribution in which the number of transitions to the low power mode is increased and the number of transitions to the sleep mode and the standby mode is decreased in the first week distribution mode. The mode distribution of the standby pattern is a mode distribution in which the number of transitions to the standby mode is increased and the number of transitions to the low power mode and the number of transitions to the sleep mode are decreased in the first week distribution mode. When changing the mode distribution, the CPU 60 keeps the total number of transition times to each power saving mode constant.

  Furthermore, the CPU 60 calculates the sum of the standby time in each pattern based on the number of transition times Tst, Tlp, Tsl to each power saving mode in each pattern and the standby time twst, twlp, twsl in each power saving mode. Then, the CPU 60 selects a pattern corresponding to the shortest total waiting time. The CPU 60 displays the number of transition times Tst, Tlp, and Tsl of each selected power saving mode on the operation unit 64 and controls the operation of the image forming apparatus 1 based on the selected pattern in the second week.

  Note that the CPU 60 performs the above operation also at the end of the second week to the end of the fourth week. However, the reduction amount Y at the end of the second week to the end of the third week is obtained by the equations (4) to (6).

Y = (S1 + 4 · S2-X) / 3 (4)
Y = (S1 + S2 + 3 · S3-X) / 2 (5)
Y = (S1 + S2 + S3 + 2 · S4-X) (6)

  Next, operations actually performed by the CPU 60 in the above operations will be described with reference to the drawings. 4 to 10 are flowcharts showing operations performed by the CPU 60.

  The user inputs the target value X using the operation unit 64. In response, the CPU 60 acquires the target value X (step S1) and stores the target value X in the RAM 62.

  Next, the CPU 60 resets the mode distribution of Table 2 stored in the RAM 62 (step S2).

  Next, the CPU 60 determines whether or not to shift the states of the fixing device 20 and the printing unit 2 to the power saving mode (step S3). In step S2, the CPU 60 determines whether or not to shift the states of the fixing device 20 and the printing unit 2 to the power saving mode based on whether or not the elapsed time of the non-job period has passed a predetermined time. When shifting to the power saving mode (Yes), the process proceeds to step S4. On the other hand, if the mode does not shift to the power saving mode (No), the process returns to step S3.

  When shifting to the power saving mode, the CPU 60 shifts the states of the fixing device 20 and the printing unit 2 to the power saving mode (step S4). Note that the CPU 60 determines which power saving mode to shift to based on the elapsed time of the non-job period. In addition, since operation | movement of step S3 and step S4 is general operation | movement, detailed description is abbreviate | omitted. Thereafter, the process proceeds to step S5.

  The CPU 60 determines whether a print job has been input (step S5). The input of the print job may be performed by the user using the operation unit 64 or may be performed by an apparatus connected to the image forming apparatus 1. If a print job has been input (Yes), the process proceeds to step S6. If no print job has been input (No), the process returns to step S5. In this case, step S5 is repeated until a print job is input.

  When a print job is input, the CPU 60 increments the number of transitions to the power saving mode that has been shifted in step S4 in the mode distribution of Table 2 (step S6). Thereafter, the CPU 60 causes the printing unit 2 and the fixing device 20 to execute a print job (step S7).

  Next, the CPU 60 determines whether or not one week has elapsed since the mode distribution was reset in step S2 (step S8). If one week has passed (Yes), the process proceeds to step S9. If one week has not elapsed (No), the process returns to step S3. In this case, steps S3 to S8 are repeated until one week elapses.

  When one week has elapsed, the CPU 60 calculates the power consumption amount Sn and the standby time TWn (step S9). Here, step S9 will be described in more detail with reference to the drawings. FIG. 5 is a flowchart of the subroutine of step S9.

  The CPU 60 reads the mode distribution shown in Table 2 from the RAM 62 (step S91).

Next, the CPU 60 calculates the power consumption amount Sn during the non-job period in the nth week (n is an integer of 1 to 5) based on the equation (7) (step S92).
Sn = Tst · Wst + Tlp · Wlp + Tsl · Wsl (7)

Next, the CPU 60 calculates the standby time TWn of the non-job period in the nth week (n is an integer of 1 to 5) based on the equation (8) (step S93).
TWn = Tst · twst + Tlp · twlp + Tsl · twsl (8)

  Thereafter, the process proceeds to step S10.

  The CPU 60 determines the number of transition times Tst, Tlp, Tsl to each power saving mode in each pattern (step S10). Here, step S10 will be described in more detail with reference to the drawings. FIG. 6 is a flowchart of the subroutine of step S10.

  The CPU 60 reads the mode distribution shown in Table 2 from the RAM 62 (step S101).

  Next, the CPU 60 calculates a reduction amount Y based on the target value X using the equations (3) to (6) (step S102).

  Next, the CPU 60 determines the number of transition times Tst, Tlp, Tsl to each power saving mode in the sleep pattern (step S103). Here, step S103 will be described in more detail with reference to the drawings. FIG. 7 is a flowchart of the subroutine of step S103. Table 5 is a table showing the number of transitions, power consumption, and standby time in the nth week and each pattern.

  The CPU 60 changes the number of transition times Tst, Tlp, Tsl (step S301). Specifically, as shown in Table 5, the CPU 60 increases the number of sleep mode transitions from Tsl to Tsl + ΔTsl. On the other hand, the CPU 60 decreases the number of times of transition to the standby mode from Tst to Tst−ΔTsl1. The CPU 60 decreases the number of times of transition to the low power mode from Tlp to Tlp−ΔTlp2. Note that the relationship ΔTsl = ΔTsl1 + ΔTsl2 is established.

  Next, the CPU 60 calculates the power consumption amount Ssl during the non-job period in the sleep pattern based on the equation (9) (step S302).

Ssl = (Tst−ΔTsl1) · (Wst−ΔWst) + (Tlp−ΔTsl2) · Wlp + (Tsl + ΔTsl) · Wsl (9)

  Next, the CPU 60 calculates the standby time TWsl of the non-job period in the sleep pattern based on the equation (10) (step S303).

TWsl = (Tst−ΔTsl1) · Δtwst + (Tlp−ΔTsl2) · twlp + (Tsl + ΔTsl) · twsl (10)

  Thereafter, the process proceeds to step S104.

  Next, the CPU 60 determines the number of transition times Tst, Tlp, Tsl to each power saving mode in the low power pattern (step S104). Here, step S104 will be described in more detail with reference to the drawings. FIG. 8 is a flowchart of the subroutine of step S104.

  The CPU 60 changes the number of transition times Tst, Tlp, Tsl (step S401). Specifically, as shown in Table 5, the CPU 60 increases the number of times of transition to the low power mode from Tlp to Tlp + ΔTlp. On the other hand, the CPU 60 decreases the number of times of transition to the standby mode from Tst to Tst−ΔTlp1. The CPU 60 decreases the number of times of transition to the sleep mode from Tsl to Tsl−ΔTlp2. Note that the relationship ΔTlp = ΔTlp1 + ΔTlp2 is established.

  Next, the CPU 60 calculates the power consumption Slp during the non-job period in the sleep pattern based on the equation (11) (step S402).

Slp = (Tst−ΔTlp1) · (Wst−ΔWst) + (Tlp + ΔTlp) · Wlp + (Tsl−ΔTlp2) · Wsl (11)

  Next, the CPU 60 calculates the standby time TWlp of the non-job period in the sleep pattern based on the equation (12) (step S403).

TWlp = (Tst−ΔTlp1) · Δtwst + (Tlp + ΔTlp) · twlp + (Tsl−ΔTlp2) · twsl (12)

  Thereafter, the process proceeds to step S105.

  Next, the CPU 60 determines the number of transition times Tst, Tlp, Tsl to each power saving mode in the standby pattern (step S105). Here, step S105 will be described in more detail with reference to the drawings. FIG. 9 is a flowchart of the subroutine of step S105.

  The CPU 60 changes the number of transition times Tst, Tlp, Tsl (step S501). Specifically, as shown in Table 5, the CPU 60 increases the number of standby mode transitions from Tst to Tstp + ΔTst. On the other hand, the CPU 60 decreases the number of times of transition to the low power mode from Tlp to Tlp−ΔTst1. The CPU 60 decreases the number of times of transition to the sleep mode from Tsl to Tsl−ΔTst2. Note that the relationship ΔTstp = ΔTst1 + ΔTst2 is established.

  Next, the CPU 60 calculates the power consumption Sst during the non-job period in the sleep pattern based on the equation (13) (step S502).

Sst = (Tst + ΔTst) · (Wst−ΔWst) + (Tlp−ΔTst1) · Wlp + (Tsl−ΔTst2) · Wsl (13)

  Next, the CPU 60 calculates the standby time TWst of the non-job period in the sleep pattern based on the formula (14) (step S503).

TWst = (Tst + ΔTst) · Δtwst + (Tlp−ΔTst1) · twlp + (Tsl−ΔTst2) · twsl (14)

  Thereafter, the process proceeds to step S11.

  The CPU 60 selects which pattern is to be applied (step S11). At this time, the CPU 60 selects a pattern corresponding to the shortest standby time. Here, step S11 will be described with reference to the drawings. FIG. 10 is a flowchart of the subroutine of step S11.

  CPU 60 determines whether or not standby time TWsl is shorter than standby time TWlp (step S601). When the standby time TWsl is shorter than the standby time TWlp (Yes), the process proceeds to step S602. If the standby time TWsl is not shorter than the standby time TWlp (No), the process proceeds to step S604.

  When the standby time TWsl is shorter than the standby time TWlp, the CPU 60 determines whether or not the standby time TWsl is shorter than the standby time TWst (step S602). If the standby time TWsl is shorter than the standby time TWst (Yes), the process proceeds to step S603. If the standby time TWsl is not shorter than the standby time TWst (No), the process proceeds to step S604.

  When the standby time TWsl is shorter than the standby time TWst, the CPU 60 determines that the standby time TWsl is the shortest and selects a sleep pattern (step S603). Thereafter, the process proceeds to step S12.

  In step S604, the CPU 60 determines whether or not the standby time TWlp is shorter than the standby time TWst (step S604). If the standby time TWlp is shorter than the standby time TWst (Yes), the process proceeds to step S605. If the standby time TWlp is not shorter than the standby time TWst (No), the process proceeds to step S606.

  When the standby time TWlp is shorter than the standby time TWst, the CPU 60 determines that the standby time TWlp is the shortest and selects the low power pattern (step S605). Thereafter, the process proceeds to step S12.

  When the standby time TWlp is not shorter than the standby time TWst, the CPU 60 determines that the standby time TWst is the shortest and selects a standby pattern (step S606). Thereafter, the process proceeds to step S12.

  In step S12, the CPU 60 determines whether one month has elapsed since the target value X was input in step S1 (step S12). If one month has elapsed, the process returns to step S1. If one month has not elapsed, the process returns to step S2. In this case, in the next week, the CPU 60 displays the mode distribution of the pattern selected in step S11 on the operation unit 64, and controls the operations of the printing unit 2 and the fixing device 20 based on the pattern. Above, description of the operation | movement which CPU60 performs is complete | finished.

(effect)
According to the image forming apparatus 1 configured as described above, power consumption can be reduced. More specifically, in the image forming apparatus 1, the number of transition times Tst, Tlp, Tsl to each power saving mode is changed every weekend so as to be within the target value X. The CPU 60 controls the operations of the printing unit 2 and the fixing device 20 based on the number of transition times Tst, Tlp, and Tsl after the change, thereby reducing the power consumption of the image forming apparatus 1.

  Further, according to the image forming apparatus 1, it is possible to prevent the waiting time TWn until the job is executed from increasing. More specifically, the CPU 60 consumes the power consumption amount Sn in the non-job period based on the power consumption amount Wst−ΔWst, Wlp, Wsl in each power saving mode and the number of times Tst, Tlp, Tsl to shift to each power saving mode. The number Tst, Tlp, and Tsl of the number of transitions to each power saving mode are generated so that the reduction amount Y is smaller than the power amount Sn-1. Then, the CPU 60 calculates the waiting times TWst, TWlp, TWsl of the plurality of patterns based on the number of transition times Tst, Tlp, Tsl of the plurality of patterns and the waiting times twst, twlp, twsl of each power saving mode, A pattern corresponding to the shortest standby time TWst, TWlp, TWsl is selected. As a result, in the image forming apparatus 1, it is possible to prevent the standby time TWn until the job is executed from becoming long.

(Other embodiments)
The image forming apparatus according to the present invention is not limited to the image forming apparatus 1 according to the embodiment, and can be changed within the scope of the gist thereof.

  For example, in the image forming apparatus 1, the power consumption amount Sn is calculated in step S92 of FIG. 5, but the power consumption amount Sn may be a value actually measured.

  Note that in the image forming apparatus 1, an execution unit that executes a predetermined image processing job may be provided instead of the printing unit 2 and the fixing device 20 that perform image formation. Examples of the predetermined image processing include reading a document.

  The target value X may be input at the end of the first week.

  As described above, the present invention is useful for an image processing apparatus, and is particularly excellent in that it can reduce power consumption and suppress an increase in waiting time until job execution.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Printing part 20 Fixing apparatus 60 CPU
62 RAM
63 Control board 64 Operation part 66 Low voltage power supply 70 Plug

Claims (3)

An execution unit for executing a predetermined image processing job;
In a non-job period in which the execution unit is not performing a job, the standby time required for executing the job is different, and the state of the execution unit is shifted to a plurality of types of power saving modes with different power consumption amounts. Means,
Obtaining means for obtaining a first power consumption amount of the non-job period in a first predetermined period;
Counting means for counting the number of transitions to each power saving mode in the first predetermined period;
Based on the power consumption amount of each power saving mode and the number of times of transition to each power saving mode, the second power consumption amount of the non-job period in the second predetermined period having the same length as the first predetermined period. Generating means for generating the number of transitions to the respective power saving modes in the second predetermined period of a plurality of patterns, so that is reduced by a reduction amount than the first power consumption amount,
A calculating means for calculating a sum total of the waiting times of the plurality of patterns based on the number of transitions to the power saving modes of the plurality of patterns and the waiting time of each of the power saving modes;
Having
An image processing apparatus. Input means for inputting a target value of the power consumption amount of the non-job period in a third predetermined period longer than the first predetermined period;
In addition,
The generating means determines the amount of reduction based on the target value;
The image processing apparatus according to claim 1. Selection means for selecting the pattern corresponding to the smallest sum of the waiting times among the sum of the waiting times,
More
The image processing apparatus according to claim 1, wherein:

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