JP4285168B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine or a printer. More specifically, the present invention relates to an image forming apparatus having an energy saving mode for limiting the power supplied to the apparatus when an image formation pause period continues to some extent.

  Some electrophotographic image forming apparatuses generate ozone around the photoreceptor due to operation of the charger. In general, it is known that when the surface of a photoreceptor is exposed to ozone for a long time, the sensitivity of that portion deteriorates. Therefore, conventionally, a fan for adsorbing or discharging the generated ozone is provided, and this fan is driven during or after image formation to prevent deterioration of the photoreceptor.

  In addition, if the photoconductor is stopped while the generated ozone stays, a specific portion tends to be exposed to ozone because the concentration of ozone stays uneven. In order to prevent the partial deterioration of the photoconductor due to this, a technique for rotating the photoconductor at a timing such as after the end of warming up or after the end of image formation has been proposed (for example, see Patent Document 1). In the apparatus described in this document, the photosensitive member is rotated at a speed different from that at the time of image formation during the time calculated based on the driving time of the charger.

Further, in recent years, some have an energy saving mode in order to save energy consumption of the image forming apparatus. The energy saving mode is a mode in which the power of each part is automatically shut off except for the control part when the image formation suspension period continues for a predetermined time. For example, the high-voltage power supply for the charger and the power supply for the drive unit that rotationally drives the photosensitive member are cut off and stopped until the next command is input. In many cases, the length of the image formation suspension period until the start of the energy saving mode can be selected and determined by the user within a predetermined range.
JP 2002-189397 A

  However, in the conventional image forming apparatus described above, the power for rotating the photosensitive member is cut off during the energy saving mode, and therefore the photosensitive member cannot be rotated. On the other hand, if the time is set very short by the user, the energy saving mode may be started before the discharge or diffusion of ozone is sufficiently completed. That is, in this case, after the energy saving mode is started, the photosensitive member is stopped while ozone remains. As a result, the photoconductor is partially exposed to ozone as in the conventional case, which may cause partial deterioration of the photoconductor.

  Furthermore, the image forming apparatus has a rotation member such as a transfer belt or a transfer roller. Some of these are not desirable to be held in the same position for a long time because of their flexibility. This is because it can cause creep and distortion. On the other hand, there is a technique for rotating these rotating members minutely during the image formation suspension period, but in this case, there is a problem that it cannot be executed during the energy saving mode.

  The present invention has been made to solve the problems of the conventional image forming apparatus described above. That is, an object of the present invention is to provide an image forming apparatus capable of preventing partial deterioration of the photoreceptor and creep of the rotating member even when the set time until the energy saving mode is short.

The problem of resolving the image forming apparatus of the present invention made for the purpose includes a photoreceptor that rotates, a rotation driving means for rotating the photosensitive member, and a power supply unit for supplying electric power to the rotary drive means, the surface of the photoconductor An image forming apparatus for forming an image while rotating a photosensitive member by supplying power from a power supply unit to a rotation driving unit, and the power supply unit is operated in a low power consumption mode under a predetermined condition. A low power consumption mode control unit, a micro-rotation control unit that micro-rotates the rotating element at a predetermined timing during non-image formation, and a second rotational driving unit that is different from the rotational driving unit that rotationally drives the photosensitive member; , Supplying power to the second rotation drive means, the second power supply unit different from the power supply unit, and the micro-rotation control unit rotates when the power supply unit is set to the low power consumption mode by the low power consumption mode control unit Let the element rotate slightly Then, those having a power temporary supply control unit shall be the state that power to the second rotary drive means from the second power supply unit is supplied.

According to the image forming apparatus of the present invention, the photosensitive member is rotated by the rotation driving unit. The rotation driving means can be driven when power is supplied from the power supply unit. Therefore, when the power supply unit is set to the low power consumption mode by the low power consumption mode control unit, the photoconductor is not rotated as it is. In the present invention, since the second rotation driving means, the second power supply unit, and the temporary power supply return control unit are provided, if the minute rotation control unit attempts to rotate the photosensitive member minutely during the low power consumption mode, the second power supply is provided. second rotation driving means which is powered by parts is Ru can rotate the photosensitive member. Thereby, the rotation driving means can be driven, and the photosensitive member can be rotated. Accordingly, even if short setting time until the energy-saving mode, since no leaving the photoreceptor in the same environmental conditions, which is an image forming apparatus capable of preventing partial deterioration of the photoreceptor.

Further, in the present invention, the micro-rotation control unit includes the total discharge time of the charging unit, the number of continuous image formations, the total drive time of the photosensitive member, the number of image formations per unit time, and the drive time of the photosensitive member per unit time. It is desirable to set a threshold value for at least a part of the parameters, and to determine whether or not the photoconductor is to be rotated slightly based on conditions relating to the presence of parameters exceeding the threshold value.
In this way, the deterioration state of the in-machine environment such as the degree of stagnation of ozone and the degree of occurrence of uneven humidity is predicted, and the photoconductor is rotated slightly only when it is judged necessary.

The image forming apparatus of the present invention includes a rotating element, a rotation driving unit that rotationally drives the rotating element, and a power supply unit that supplies power to the rotation driving unit, and the power supply unit supplies power to the rotation driving unit. An image forming apparatus that performs image formation while rotating a rotating element, and that includes a low power consumption mode control unit that sets a power supply unit in a low power consumption mode under a predetermined condition, and a rotating element at a predetermined timing during non-image formation. A micro-rotation control unit that micro-rotates, a second rotational drive unit that is rotationally driven to rotate the rotating element, and that supplies power to the second rotational drive unit, and a second power source that is separate from the power source unit When the minute rotation control unit tries to slightly rotate the rotating element while the power source unit and the power source unit are set to the low power consumption mode by the low power consumption mode control unit, power is supplied from the second power source unit to the second rotation driving means. Is supplied and Possess a power temporary supply control unit that, rotating element, a transfer belt, a transfer roller, a fixing belt, a fixing roller, Ru one or more elements Der comprised in the group consisting of a recording material conveying member, and the document conveying member from It may be a thing.

According to the image forming apparatus of the present invention, since the second rotation driving unit, the second power supply unit, and the temporary power supply control unit are provided, the micro rotation control unit tries to rotate the rotating element microscopically during the low power consumption mode. Then, the 2nd rotation drive means supplied with electric power by the 2nd power supply part can rotate a rotation element. As a result, since the rotating elements are not left in the same posture, the image forming apparatus can prevent the rotating elements from creeping even when the set time until the energy saving mode is short.

  According to the image forming apparatus of the present invention, it is possible to prevent partial deterioration of the photoreceptor and creep of the rotating member even if the set time until the energy saving mode is short.

“First Embodiment”
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, the present invention is applied to the image forming apparatus shown in FIG.

  The image forming apparatus 1 of the present embodiment is a tandem color printer, as schematically shown in FIG. The configurations for image formation of each color of YMCK are arranged along the intermediate transfer belt 10. The configuration of each color is such that a charging device 12, an exposure device 13, a developing device 14, and a cleaner device 15 are arranged around each photosensitive drum 11. Further, a primary transfer device 16 is disposed opposite to the photosensitive drums 11 of the respective colors with the intermediate transfer belt 10 interposed therebetween. Further, a secondary transfer device 17 and a fixing device 18 are provided on the right side of the drawing, and a belt cleaner device 19 is provided on the left side of the drawing. Since these are general ones, details are omitted.

  The overall operation of the image forming apparatus 1 will be briefly described. The image forming apparatus 1 starts a printing operation when receiving a print signal. The photosensitive drum 11 is rotated and charged uniformly by the charging device 12. Next, an electrostatic latent image is formed on the surface of the photosensitive drum 11 by the exposure device 13, and the electrostatic latent image is developed with toner of each color by the developing device 14. The toner images of the respective colors are sequentially transferred to the intermediate transfer belt 10 by the primary transfer device 16 and are superimposed on the intermediate transfer belt 10. Further, the superimposed toner images are transferred to a sheet by the secondary transfer device 17 and fixed by the fixing device 18. The paper on which the color image is formed in this way is discharged out of the machine. After the toner image is transferred to the intermediate transfer belt 10, the photosensitive drum 11 is further rotated, and the transfer residual toner is collected by the cleaner device 15. Further, the untransferred toner remaining on the intermediate transfer belt 10 after the secondary transfer is collected by the belt cleaner 19.

  Next, paying attention to one of the photosensitive drums 11, the drive portion will be described. As shown in FIG. 2, the photosensitive drum 11 is rotatably held at both ends of its shaft by bearings 22 and 23, respectively. Further, a drive motor 25 is connected to an end portion held by the bearing 22 via a coupling 24. Further, as shown in FIG. 2, the image forming apparatus 1 is provided with a power supply unit 31 for supplying power to each unit and a control unit 41 for controlling the operation of each unit.

  The power supply unit 31 receives an input of an AC 100V commercial power supply 32, converts it into a necessary voltage for each part in the apparatus, and supplies power to each part. The power supply unit 31 includes an HV (high voltage power supply unit) 33 for supplying high voltage power to the charging device 12 and the like, a 24V power supply unit 34 for supplying 24V power to the drive motor 25 and the like, and 5V power to the control unit 41. A 5V power supply unit 35 and the like are provided. Each of these power supplies can be operated or stopped independently.

  The control unit 41 controls the entire image forming apparatus 1, and includes a drive control unit 42, an energy saving mode control unit 43, a minute rotation control unit 44, and the like. The drive control unit 42 is a part that performs drive control of the drive motor 25 and the like connected to the photosensitive drum 11. The energy saving mode control unit 43 is a part that counts the image formation pause time to determine the start of the energy saving mode and controls the power supply unit 31 during the energy saving mode. Further, the micro-rotation control unit 44 is a part that performs control for micro-rotating the photosensitive drum 11 during image formation suspension in order to prevent partial deterioration of the photosensitive drum 11.

  In a normal state where the image forming apparatus 1 is not in the energy saving mode, power is supplied to each unit as shown in FIG. For example, power is supplied to the control unit 41 by the 5V power supply unit 35 of the power supply unit 31. The drive motor 25 is supplied with necessary power by a 24V power source 34 and the charging device 12 by HV 33. In this state, when the image forming apparatus 1 receives a signal for instructing image formation, the control unit 41 drives each unit according to a procedure for image formation. For example, the drive control unit 42 sends a drive signal to the drive motor 25 so as to start the rotation of the photosensitive drum 11. At this time, since power is supplied to the drive motor 25 from the 24V power supply unit 34, rotation is started in accordance with the drive signal, and the photosensitive drum 11 is rotated. Here, the photosensitive drum 11 corresponds to the rotating element, the drive motor 25 corresponds to the rotation driving means, and the 24V power supply unit 34 corresponds to the power supply unit.

  When a certain number of images are formed, ozone generated by corona discharge of the charging device 12 starts to stay around the photosensitive drum 11. Furthermore, a humidity difference occurs around the photosensitive drum 11 due to water evaporated from the toner in the developing device 14 and the cleaner device 15. That is, as shown in FIG. 3, the humidity is high in the vicinity of the developing device 14 and in the cleaner device 15, and the intermediate transfer belt 10 between the developing device 14 and the cleaner device 15 has a medium humidity. Further, the humidity is low around the charging device 12 and the exposure device 13, and the ozone concentration is high immediately above the charging device 12.

  If left in such an uneven state, a difference in sensitivity occurs in the photosensitive drum 11. For example, ozone degradation may occur in a portion exposed to ozone, sensitivity may be reduced, and image defects (white spots) may occur. Alternatively, the photosensitive drum 11 has a sensitivity difference depending on humidity, and the sensitivity is higher in the high humidity portion than in other portions. As a result, a normal electrostatic latent image is not formed at the time of exposure, and an image defect (black band) may occur.

  In order to prevent the occurrence of these image defects, in the image forming apparatus 1, the photosensitive drum 11 is rotated little by little during the image formation pause. That is, after forming a predetermined number of images or more, the photosensitive drum 11 is rotated by a minute angle by the minute rotation control unit 44 at a predetermined timing. For example, rotating the photosensitive drum 11 for about 300 ms is repeated about 10 to 15 times at intervals of 30 seconds or 60 seconds. The photosensitive drum 11 rotates about a quarter (about 90 degrees) by the rotation of about 300 ms. Thus, by rotating little by little at intervals, it is possible to prevent the same position of the photosensitive drum 11 from being exposed to the same environment and to prevent the occurrence of sensitivity unevenness.

  Here, the interval and the number of times the micro rotation is repeated are controlled according to the control table 45 stored in the micro rotation control unit 44. The control table 45 is stored by being classified according to the in-machine environment of the image forming apparatus 1 as shown in FIG. The image forming apparatus 1 detects the temperature and humidity state in the apparatus, and determines which control table 45 is used based on the detection result. 4A shows a case where the inside of the apparatus is low temperature and low humidity, FIG. 4B is a table used in the case of a medium temperature middle chamber, and FIG. 4C is a table used in the case of high temperature and high humidity. In this figure, the column for image formation pause time indicates the time since the image formation was paused after the execution of the minute rotation was decided. Each minute rotation is performed at the time timing indicated by the circles. .

  On the other hand, when a predetermined time elapses without receiving an image forming signal or inputting a command, the image forming apparatus 1 enters an energy saving mode state by the energy saving mode control unit 43. In this state, as shown in FIG. 5, the power supply unit 31 leaves only the 5V power supply unit 35 and stops the other parts. That is, the 24V power supply 34 that is the power supply of the drive motor 25 for rotating the photosensitive drum 11 is stopped. In FIG. 5, a broken line indicates that the line is connected but no power is supplied. Therefore, in this state, even if a drive signal is output from the drive control unit 42 to the drive motor 25, the drive motor 25 is not driven by itself.

  Therefore, the minute rotation control unit 44 sends an instruction to send a drive signal to the drive motor 25 to the drive control unit 42 when the timing for performing the minute rotation is in the energy saving mode, and also the energy saving mode control unit. An instruction to temporarily operate the 24V power supply unit 34 is sent to 43. In response to this instruction, the energy saving mode control unit 43 sends a signal for temporarily operating the 24V power supply unit 34 to the power supply unit 31. As a result, power is supplied to the drive motor 25, so that the photosensitive drum 11 can be rotated slightly by receiving a drive signal. Further, the minute rotation control unit 44 stops the 24V power supply unit 34 again via the energy saving mode control unit 43 when one minute rotation is completed. At this time, the energy saving mode control unit 43 functions as a power supply temporary return control unit.

  Next, the control timing of the minute rotation control unit 44 will be described with reference to the time table of FIG. In FIG. 6, the “driving state of the photosensitive drum 11”, “cumulative driving time of the photosensitive drum 11 (Tpc)”, “cumulative image formation pause time (Tstop)”, and “micro rotation control” are sequentially performed from the top. Show. In the “driving state of the photosensitive drum 11”, “driving” is indicated when the image forming apparatus 1 is in the image forming operation or the image stabilizing operation, and “rest” is indicated in other cases. Then, Tpc is obtained by accumulating the time during which the “driving state of the photosensitive drum 11” is “driving”. Further, Tstop is an accumulation of times during which the “driving state of the photosensitive drum 11” is “pause”.

  The minute rotation control unit 44 determines execution of minute rotation when Tpc exceeds a predetermined threshold value (Tpc−max). However, if the photosensitive drum 11 is being driven such as during an image forming operation, the image forming operation is prioritized and the minute rotation is not immediately executed. Waiting for the “driving state of the photosensitive drum 11” to become “pause”, the execution timing is determined from the control table 45 of FIG. 4 selected according to the in-machine environment. Further, at each timing indicated by a circle in the control table 45, if the image forming operation is not being performed, a minute rotation is executed. Once execution of minute rotation is determined, the control table 45 repeats the number of times set in advance.

  As can be seen from the control table 45, the number of micro rotations varies greatly depending on the in-machine environment, and continues for about 15 minutes at low temperature and low humidity. On the other hand, the image formation pause time until the start of the energy saving mode is set by the user and can be set to about 10 minutes at the shortest. For this reason, depending on conditions, the energy saving mode may be started before the minute rotation is completed up to the set number of times. When the energy saving mode is started, the HV 33, 24V power supply unit 34, etc. are stopped as shown in FIG. When the minute rotation execution timing comes in this state, the minute rotation control unit 44 temporarily operates the 24V power supply unit, and once again performs minute rotation, and then stops again.

  In the time table of FIG. 6, when Tstop exceeds a predetermined threshold value (Tstop-max), Tpc that has been accumulated and held until then is cleared. This is because when the image formation is suspended, the ozone accumulated until then is diffused or discharged to some extent, and the unevenness in humidity distribution is also eliminated to some extent. When Tstop reaches the energy saving mode start time set by the user and the energy saving mode is started, Tstop is cleared. Further, Tstop is not accumulated during the energy saving mode.

  Here, Tpc, that is, the cumulative driving time of the photosensitive drum 11 is used as a determination criterion for the minute rotation control unit 44 to determine execution of the minute rotation. This criterion is not limited to this. For example, the number of printed sheets, the accumulated discharge time of the charging device 12, and the like may be used. Alternatively, a threshold value can be set for each of the continuous printing and the total per unit time, and judgment can be made by a combination thereof.

  As described above in detail, according to the image forming apparatus 1 of the present embodiment, when the accumulated driving time of the photosensitive drum 11 reaches a predetermined time, the minute rotation control unit 44 determines execution of minute rotation. Is done. The number and timing of minute rotations are set by a control table 45 stored in the minute rotation control unit 44. Further, if it is in the energy saving mode when trying to execute the minute rotation, the minute rotation control unit 44 instructs the energy saving mode control unit 43 to temporarily operate the 24V power supply unit 34. Therefore, the drive motor 25 can be driven for minute rotation even in the energy saving mode. Thereby, according to this image forming apparatus 1, even if the set time until the energy saving mode is short, the partial deterioration of the photosensitive drum 11 can be prevented.

“Second Embodiment”
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, the image forming apparatus according to the first embodiment further includes a second drive unit for slightly rotating the photosensitive drum 11. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof is omitted.

  In the image forming apparatus of this embodiment, as shown in FIG. 7, a second drive motor 51 is provided on the side of the photosensitive drum 11 held by the bearing 23. Further, the end portion on the bearing 23 side protrudes from the bearing 23 and is formed long, and a gear is provided at the tip portion. A gear that meshes with the gear at the end is also formed on the rotation shaft of the drive motor 51. That is, when these gears are engaged, the photosensitive drum 11 is rotated by the driving force of the driving motor 51. Here, the drive motor 51 may be slightly inferior in driving force and control precision as compared with the first drive motor 25. The drive motor 51 is a motor that can be driven by DC 5V power. Further, in the present embodiment, the control unit 41 is provided with a second drive control unit 52 for controlling the drive motor 51. Here, the drive motor 51 corresponds to the second rotational drive means.

  This embodiment differs from the image forming apparatus according to the first embodiment in a control method in the case where execution of minute rotation is instructed during the energy saving mode. In this embodiment, when the execution of minute rotation is instructed and the energy saving mode is in effect, the coupling 24 is separated from the end of the photosensitive drum 11 and the drive motor 25 and the photosensitive drum 11 are separated. Further, the drive motor 51 is brought into contact with the end portion on the bearing 23 side, and the gears are engaged with each other. After that, the minute rotation control unit 44 instructs the second drive control unit 52 to drive the drive motor 51. The drive power of the drive motor 51 is taken from the 5V power supply unit 35, and the 5V power supply unit 35 is not stopped. Here, the 5V power supply unit 35 corresponds to a second power supply unit, and the second drive control unit 52 functions as a temporary power supply control unit.

  As described in detail above, in the image forming apparatus according to the present embodiment, as in the first embodiment, even if the set time until the energy saving mode is short, partial deterioration of the photoconductor can be prevented. it can.

“Third Embodiment”
The third embodiment embodying the present invention will be described below. Since the configuration of the present embodiment is the same as that of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In addition to the photosensitive drum 11, for example, a transfer roller included in the intermediate transfer belt 10, the primary transfer device 16 or the secondary transfer device 17, a fixing belt or a fixing roller of the fixing device 18, a recording material or a document conveying member, etc. Includes a rotating part. Some of these rotating parts can cause creep if held in the same position for a long time. Therefore, these rotating portions may be rotated slightly at a predetermined timing similarly to the photosensitive drum 11. Even in this case, if the rotation timing is in the energy saving mode, the minute rotation control unit 44 instructs the energy saving mode control unit 43 to temporarily operate the 24V power supply unit 34.

  As described above, in the image forming apparatus according to the present embodiment, it is possible to prevent the rotating member from creeping even if the set time until the energy saving mode is short.

Note that this embodiment is merely an example, and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof.
For example, in each of the above-described embodiments, the end of the photosensitive drum 11 is connected to the coupling 24 and the rotation of the drive motor 25 is transmitted. May be transmitted as the rotation of the photosensitive drum 11. For example, a gear drive system in which a gear is provided at the end of the shaft of the photosensitive drum 11 may be used.
Further, for example, although a tandem color printer is used, the present invention is not limited to this, and an image forming apparatus such as a copier or a fax machine or a monochrome machine may be used.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an exemplary embodiment. It is explanatory drawing which shows the structure for the rotational drive of a photoconductor drum. FIG. 6 is an explanatory diagram showing a state around a photosensitive drum. It is explanatory drawing which shows the example of the control table which controls the timing of micro rotation drive. It is explanatory drawing which shows the state in the energy-saving mode of the structure for the rotational drive of a photoconductor drum. 3 is a time table showing operation timing of the image forming apparatus. It is explanatory drawing which shows the structure for the rotational drive of the photosensitive drum of 2nd Embodiment. It is explanatory drawing which shows the state in the energy saving mode of the structure for the rotational drive of the photosensitive drum of 2nd Embodiment.

Explanation of symbols

1 Image forming apparatus 11 Photosensitive drum (photosensitive member, rotating element)
12 Charging device (charging unit)
25 Drive motor (rotation drive means)
34 24V power supply (power supply)
35 5V power supply (second power supply)
43 Energy saving mode control unit (low power consumption mode control unit, power supply temporary recovery control unit)
44 Micro-rotation control unit 51 Drive motor (second rotation drive means)
52 2nd drive control part (power supply temporary supply control part)

Claims (3)

A rotating photosensitive member; a rotational driving unit that rotationally drives the photosensitive member; a power supply unit that supplies power to the rotational driving unit; and a charging unit that charges the surface of the photosensitive member. In an image forming apparatus for forming an image while rotating the photosensitive member by supplying power to the rotation driving unit,
A low power consumption mode control unit for setting the power supply unit to a low power consumption mode under a predetermined condition;
A micro-rotation control unit that micro-rotates the photoconductor at a predetermined timing during non-image formation;
A second rotational drive means separate from the rotational drive means for rotationally driving the photoreceptor;
A second power supply unit different from the power supply unit for supplying power to the second rotation driving means;
If the micro-rotation control unit tries to rotate the photoconductor microscopically when the power source unit is set to the low power consumption mode by the low power consumption mode control unit, the second rotational drive is performed from the second power source unit. an image forming apparatus, comprising a power temporary supply control unit shall be the state that power to the unit is supplied. The image forming apparatus according to claim 1,
The micro-rotation control unit includes parameters for the total discharge time of the charging unit, the number of continuous image formations, the total drive time of the photoconductor, the number of image formations per unit time, and the drive time of the photoconductor per unit time. An image forming apparatus, wherein a threshold value is set for at least a part, and whether or not the photoconductor is to be slightly rotated is determined according to a condition relating to the presence of a parameter exceeding the threshold value. One or more rotating elements included in the group consisting of a transfer belt, a transfer roller, a fixing belt, a fixing roller, a recording material conveying member, and a document conveying member, a rotation driving means for rotating the rotating element, and the rotation driving An image forming apparatus that forms an image while rotating the rotating element by supplying power from the power supply unit to the rotation driving unit.
A low power consumption mode control unit for setting the power supply unit to a low power consumption mode under a predetermined condition;
A micro-rotation control unit that micro-rotates the rotary element at a predetermined timing during non-image formation; a second rotary drive unit that is different from the rotary drive unit that rotationally drives the rotary element;
A second power supply unit different from the power supply unit for supplying power to the second rotation driving means;
If the minute rotation control unit attempts to slightly rotate the rotating element when the power source unit is set to the low power consumption mode by the low power consumption mode control unit, the second rotation drive is performed from the second power source unit. An image forming apparatus comprising: a temporary power supply control unit configured to supply power to the unit.

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