JP2008046516A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that strikes a balance between energy saving and convenience. <P>SOLUTION: The apparatus shifts to a low power mode when shift time T elapses without requiring image formation. The apparatus includes a shift time setting part which sets the shift time T' taken to shift to the low power mode next time to be shorter than T when the image formation is required in a period A (period that elapsed time after starting the low power mode is under t1), sets the shift time T' to be the same as T when the image formation is required in a period B (period that the elapsed time is equal to or above t1 and under t2), and sets the shift time T' to be longer than T when the image formation is required in a period C (period that the elapsed time is equal to or above t2). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, or a facsimile machine.

  In recent years, energy saving has been achieved in various devices, and an attempt has been made to reduce power consumption in image forming apparatuses. As a typical method for reducing power consumption, image formation is performed in a low power mode that further reduces power consumption compared to the standby mode by reducing power supply to the display unit or heater during non-image formation. A technique for operating the apparatus may be mentioned.

For example, the invention of Patent Document 1 aims to provide an image forming apparatus that allows the user to grasp the power consumption value of the terminal used by the power consumption calculation function, and has the following configuration. That is, in this image forming apparatus, when the initialization of each part is completed after the power is turned on, the timer starts counting, the power consumption value in the standby state is calculated, and when the transition condition to the energy saving mode is detected during the standby state, Transition to energy saving mode and shut down unnecessary power systems.
JP 2002-225395 A (released on August 14, 2002)

  In the above conventional technique, the user sets conditions for the user himself / herself to enter the energy saving mode. Therefore, the user individually determines whether to enhance the energy saving effect or to improve the convenience by speeding up the startup. Further, since it is a burden for the user to set such conditions, it is rare to change the conditions once set. Therefore, depending on the set conditions, there has been a problem that the energy saving effect as expected cannot be obtained, or conversely, the convenience is remarkably inferior.

  In view of such problems, an object of the present invention is to provide an image forming apparatus capable of achieving both an energy saving effect and convenience.

  An image forming apparatus according to the present invention is an image forming apparatus that performs image formation in response to an image formation request. The image forming apparatus accepts an image formation request from the outside, and the reception unit accepts the image formation request after image formation. When a predetermined transition time elapses, a power control unit that executes a low power mode that reduces power consumption in the entire image forming apparatus from the standby state, and a first image after the start of the low power mode by the transition time T If the timer that measures the elapsed time until the formation request is received and the elapsed time is less than a predetermined range, the transition time T ′ at the time of transition to the next low power mode is set longer than T, and the elapsed time A transition time setting unit that sets the transition time T ′ to be the same as T if it is within the predetermined range, and sets the transition time T ′ to be shorter than T if the elapsed time exceeds the predetermined range; Obtain.

  If the time from the transition to the low power mode to the first image formation request is shorter than a predetermined time by the transition time setting unit, the transition time setting unit increases the transition time T ′ so that the next low power mode The transition to can be delayed. In this way, when an image forming operation is frequently required, it is possible to reduce the return power from the low power mode and to shorten the time taken for the start-up to improve the convenience. Conversely, if the time from the transition to the low power mode to the first image formation request is longer than a certain time, the transition time T ′ is set to be short so that the standby time is shortened and consumed in the standby state. Power consumption can be reduced.

  Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments. Moreover, a conventionally well-known technique can be utilized suitably about the structure which does not mention especially in the following description.

[1. MFP)
FIG. 1 is a block diagram showing a main configuration of a multifunction peripheral (image forming apparatus) 1 according to an embodiment of the present invention. In this embodiment, an example of an image forming apparatus includes a multifunction peripheral that can function as a printer, a facsimile machine, and a copier. However, the present invention is not limited to this and can be implemented as various image forming apparatuses.

  As shown in FIG. 1, the multi-function device 1 has an operation panel 2 that accepts input from a user, an interface 3 for exchanging image data with an external computer via a network, and for exchanging image data with an external facsimile. By providing the communication unit 4, it is possible to accept an image formation request from the outside. Further, the multifunction device 1 is formed of a liquid crystal display element or the like, and includes a display unit 5 for showing information about image processing to the user, a printer unit 6 having image forming and scanner functions, and the like. A control device 7 for controlling the members, a timer group 8 and the like are provided. The operation panel 2, the interface 3, and the communication unit 4 can function as a receiving unit that can receive an image formation request from the outside.

  The control device 7 includes a microcomputer system including a CPU, RAM, ROM, various drivers and various IOs, and includes a transition time setting unit 72 and a power control unit 73.

  The power control unit 73 can execute the standby mode and the low power mode as will be described later by controlling each member in the multi-function device 1 in accordance with the transition time set by the transition time setting unit 72. The transition time setting unit 72 determines the transition time based on the elapsed time from when the multifunction device 1 transitions to the low power mode until the operation panel 2, I / F 3, communication unit 4, etc. accepts a new image formation request. Can be set. The transition time setting method will be described later.

  The timer group 8 includes a timer a and a timer b, which will be described later, and is used for switching from the standby mode to the low power mode by the power control unit 73, setting the transition time by the transition time control unit 72, and the like.

  A more specific configuration of the multifunction machine 1 will be described with reference to FIG. FIG. 2 is a front view showing a main configuration of the multifunction machine 1 with the printer unit 6 as the center.

  As shown in FIG. 2, the multi function device 1 includes a discharge unit 80 and a main body 90, and as a printer unit 6, an image forming unit 61 (61 </ b> Y, 61 </ b> M, 61 </ b> C, 61 </ b> K), a transfer unit 62, a fixing device 63, a supply unit. A paper transport unit 64, a scanner (not shown), an internal interface unit, and the like are provided.

  The image forming unit 61 employs an electrophotographic method, includes a rotatable photosensitive drum 611, and includes a cleaning unit 612, a charging unit 613, a laser unit 614, and a developing unit along the rotation direction of the photosensitive drum 611. Prepare each. The developing unit includes a developing roller 616 that transports toner onto the photosensitive drum 1, a supply roller 617 that supplies toner to the developing roller 616, and a toner storage unit 619 that stores toner of each color.

  At the time of image formation, after the charging unit 613 uniformly charges the photosensitive drum 611, the laser unit 614 draws an electrostatic latent image by discharging with light, and the developing unit develops the electrostatic latent image with toner of each color. To do. After the transfer by the transfer unit 62, the cleaning unit 612 removes the residual toner after transfer from the photosensitive drum 611.

  The image developed by the developing unit is transferred onto the paper by the transfer unit 62. The transfer unit 62 includes a transfer belt 621, a driving roller 622, and a transfer unit 623. The transfer belt unit 26 sucks the paper conveyed by the paper feeding / conveying unit 64 by the transfer belt 621 and the driving roller 622. Then, it is conveyed to the position where it contacts each photosensitive drum 611 with good timing. Then, the toner image on the photosensitive drum 611 is transferred onto a sheet by the transfer unit 623.

  The fixing device 63 fixes the toner image on the paper by thermocompression bonding with the heat roller 631. A control circuit 90 that controls the temperature of the heat roller 631 is connected to the fixing device 63.

  The sheet on which the toner image has been fixed in this way is conveyed by the sheet feeding / conveying unit 64 to the discharge unit 80 provided outside the image forming apparatus main body 90, and printing is completed.

[2. (Standby mode / Low power mode)
The standby mode and the low power mode will be described with reference to FIG. FIG. 3 is a flowchart showing the processing operation for mode switching of the multifunction machine 1.

  When the power is turned on, the MFP 1 performs a startup operation such as initial setting (S1).

  The activated multifunction device 1 enters the standby mode (S2). The standby mode is a state in which each unit is kept in a state that can quickly respond to an image formation request. Although the specific operation in the standby mode is not limited, for example, the temperature of the heat roller 631 is the same as or lower than that at the time of image formation while the paper transport unit 64 and the like is stopped, but can easily return to the temperature at the time of image formation. You may hold | maintain at the temperature which can be performed. The display unit 5 may be held in a state where a screen indicating that printing is possible is displayed.

  At the same time, the standby time is counted by the timer a (S3). The multifunction device 1 waits until an image request is accepted (Yes in S4), the standby time reaches T (Yes in S7), or an instruction to turn off the power is accepted via the operation panel 2 or the like (Yes in S13). The state continues and the count of the waiting time by the timer a is also continued.

  When the image formation request is accepted (Yes in S4), the count of the timer a is reset (S5), and the image forming operation by the printer unit 6 is executed (S6). Thereafter, the multifunction device 1 enters the standby mode again.

  On the other hand, when the standby time reaches T with no image formation request (No in S4, Yes in S7), the count of the timer a is reset (S8), and the multi function device 1 shifts to the low power mode (S9). The low power mode is continued until there is an image formation request (Yes in S10) or an instruction to turn off the power (No in S10 and Yes in S12). The low power mode is a mode in which power consumption is further reduced than in the standby mode. Although a specific operation is not limited, the power control unit 73 may cut off or switch a part of the power supply circuit to each unit in the multi-function device 1, particularly the printer unit 6 and the display unit 5, to another circuit. More specifically, the power control unit 73 energizes only a minimum member that receives an image formation request from the outside, such as the communication unit 4, and heats the display unit 5, the printer unit 6, particularly the control circuit 90. Processing such as cutting off power supply to the roller 631 can be performed.

  If there is an image formation instruction, the power control unit 73 resumes the power supply to the members necessary for the image forming operation such as the printer unit 6 and the display unit 5 (return operation, S11). Note that members other than the image formation request, such as the display unit 5 and the like, are not limited to the image formation request, and are restored when any of the operation panel 2, the interface 3, and the communication unit 4 receives an input. May be.

  After the return, when the image forming operation (S6) is finished, the multi-function device 1 repeats the same operation from step S2 again.

  FIG. 4 is a graph illustrating an example of a change in power consumption of the multifunction machine 1, where the horizontal axis represents time and the vertical axis represents power consumption. As shown in FIG. 4, when returning from the low power mode, a large amount of electric power that is the same as that at startup is required. On the other hand, not much power is required to perform the image forming operation from the standby mode. However, the power consumption during the standby mode is greater than the power consumption during the low power mode.

[3. (How to set the transition time)
In the multifunction device 1, the transition time T from the start of the standby mode to the start of the low power mode is variable. The multifunction device 1 can perform the processing operation shown in FIG. 5 in order to set the transition time T. The processing operation in FIG. 5 is the same as the processing operation in FIG. 3 except that steps S101 to S103 are added. For this reason, the same steps are denoted by the same reference numerals or illustrations are omitted as appropriate.

  As described above, when the standby time reaches the transition time T, the transition to the low power mode is executed (S9). The elapsed time after shifting to the low power mode is counted by the timer b (S101). When there is an image formation request (Yes in S10), a new transition time T ′ is set by the transition time setting unit 72 based on the counted time (S102). The timer b is reset (S103), and the power control unit 73 restores the power state of the multifunction machine 1 (S11). The subsequent operation is as described in FIG.

  The transition time setting in step S102 will be described more specifically. The count result of the timer b is the elapsed time from the start of the low power mode to the reception of the image formation request. The transition time setting unit 72 can change the transition time to the next low power mode according to the difference between the elapsed time and the predetermined range. This predetermined range is shown as a period B (a period in which the elapsed time is not less than t1 and less than t2) in FIG. The “predetermined range” is a range that can be arbitrarily set, and is not particularly limited as long as the object of the present invention can be achieved. For example, t2 can be a time during which the temperature of the heat roller 631 is sufficiently lowered.

  The transition time T ′ newly set by the transition time setting unit 72 can be expressed as T ′ = T + ΔT using the previous transition time T. The transition time setting unit 72, when the elapsed time until the image forming operation is requested after the start of the low power mode (elapsed time 0) is less than the predetermined range, that is, the period A (the period in which the elapsed time is 0 or more and less than t1) ), A transition time T ′ longer than the transition time T is set anew as ΔT> 0 (FIG. 6). When the elapsed time is within the predetermined range, that is, when the image formation request is accepted within the period B, the transition time T is maintained as T = 0 (FIG. 7). When the elapsed time is longer than the predetermined range, that is, when an image formation request is received within the period C (a period equal to or longer than t2), a transition time T ′ shorter than the transition time T is set as ΔT <0. It can be newly set (FIG. 8).

  More specifically, for example, a table in which the elapsed time and ΔT are associated with each other is stored in the control device 7 in advance, and the transition time setting unit 72 selects ΔT corresponding to the elapsed time from this table. It may be. At this time, it is preferable that the absolute value of ΔT is set so that the elapsed time increases as the distance from the range of the period B increases. The transition time setting unit 72 can also set ΔT to a number obtained by multiplying the difference between the elapsed time and the range of the period B by a constant (an increase rate of T with respect to the elapsed time). The above table and this constant may be set in advance during the manufacturing process, or may be settable by the user.

  Such a transition time changing operation may be always performed, or the user can select a specific mode such as “transition time changing mode” via the display unit 6 and the operation panel 2, and this mode is selected. It may be performed only when it is done.

  Further, the transition time may be set to the initial setting value until the transition time setting unit 72 changes the setting. This initial set value may be preinstalled in the control device 7 at the time of manufacture, or may be set by the user.

  As described above, the multi-function device 1 according to the present embodiment uses the timer b to measure the occurrence time of the next image formation request (return request during the low power mode) after completion of image formation, and uses the time from this occurrence time. When it is determined that the frequency is high, the transition time setting unit 72 can set the transition time longer, and when it is determined that the usage frequency is low, the transition time can be set shorter. In this way, the transition time setting unit 72 can set the transition time according to the usage status of the multifunction device 1, so that both energy saving and convenience can be achieved. Further, since the multifunction device 1 can automatically set the transition time, it does not require detailed transition time setting by the user, and is very convenient for the user.

  In the above embodiments, the techniques described as different embodiments can be used in combination, and the technical scope obtained by combining known techniques with these techniques is also included in the present invention. Not too long.

1 is a block diagram showing a main configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a front view showing a printer unit and its peripheral members of the image forming apparatus. 6 is a flowchart illustrating a standby mode and low power mode execution operation in the image forming apparatus. 6 is a graph showing power consumption with respect to elapsed time in the image forming apparatus. 10 is a flowchart showing an image forming operation request status totaling operation when setting a transition time from a standby mode to a low power mode. The graph which shows the power consumption when changing transition time T to T 'when (DELTA) T> 0. The graph which shows the power consumption when the transition time T is changed to T ′ when ΔT = 0. The graph which shows the power consumption when the transition time T is changed to T ′ when ΔT <0.

Explanation of symbols

1 MFP (image forming device)
2 Operation panel (reception part)
3 Interface (Reception Department)
4 Communication Department (Reception Department)
DESCRIPTION OF SYMBOLS 5 Display part 6 Printer part 7 Control apparatus 72 Transition time setting part 73 Power control part 8 Timer group

Claims (1)

An image forming apparatus that executes image formation in response to an image formation request,
A reception unit for receiving an image formation request from the outside;
A power control unit that executes a low power mode for reducing power consumption in the entire image forming apparatus from a standby state when a predetermined transition time has elapsed without image reception request received by the reception unit after image formation;
A timer for measuring an elapsed time from when the low power mode is started by the transition time T until the first image formation request is received;
If the elapsed time is less than the predetermined range, the transition time T ′ at the time of transition to the next low power mode is set longer than T, and if the elapsed time is within the predetermined range, the transition time T ′ is set. And a transition time setting unit that sets the transition time T ′ to be shorter than T when the elapsed time exceeds the predetermined range.

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