JP2012103580A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus with small power consumption, which has a plurality of sensors as triggers for recovering from a sleep mode.SOLUTION: An image forming apparatus includes a main control unit 300, first to third sensors 312, 314, and 316 for generating signals as triggers to recover from a sleep mode to a normal operation mode, and a sub control unit 310. When the sleep mode is set, the sub control unit 310 performs duty control for intermittently controlling the respective first to third sensors at a fixed period so that periods for supplying power to the respective sensors do not overlap with each other, checks an output of the respective sensors during their operating periods, and imparts a trigger signal to the main control unit 300 when detecting an event to be a trigger for moving to the normal operation mode.

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus capable of reducing power consumption in a sleep mode.

  Some image forming apparatuses such as multifunction peripherals shift from a normal operation mode to a sleep mode (power saving mode) after a predetermined period of time has passed. In the normal operation mode, power is constantly supplied to each function unit of the image forming apparatus. Therefore, each functional unit can start operation immediately in response to an instruction from the user. On the other hand, in the sleep mode, power is supplied only to the sensor that serves as a trigger for returning from the sleep mode to the normal operation mode. Electric power is not supplied to other functional units. Therefore, the power consumption in the sleep mode may be less than the power consumption in the normal operation mode. Therefore, the sleep mode is frequently used in a standby state or the like.

  However, the sleep mode is often used for a long time. Even if the image forming apparatus is set to the sleep mode, the power consumption becomes a large value over a long period of time. For this reason, various methods for reducing power consumption in the sleep mode have been proposed, one of which is duty control. In this specification, control for turning on / off a power source for supplying power to each functional unit is referred to as duty control.

  Referring to FIG. 19, the amount of power consumed is compared between when the sensor power supply is duty controlled and when it is not. When duty control is not performed, the sensor power supply is always on. On the other hand, when performing duty control, the sensor power supply repeats an on state and an off state (shaded portion in FIG. 19) at a constant cycle. The amount of power consumed by the image forming apparatus is determined by the length of time that the power is on (hereinafter referred to as “power on time”). As the on-state time is shorter, the time during which no power is supplied to the sensor is longer, and thus the power consumption is reduced.

  Patent Document 1 described later discloses a technique for duty-controlling a driving power source to a driver that drives an image sensor. When duty control is performed, the power consumption of the image reading apparatus is reduced compared to the power consumed when the duty control is not performed.

JP-A-10-257209

  In the technique disclosed in Patent Document 1, the target for duty control is fixed only to the drive power supply to the driver. However, in the case of the image forming apparatus, there are a plurality of sensors that are triggers for returning from the sleep mode. Even if the technique disclosed in Patent Document 1 is applied to each sensor as it is, the power saving effect is recognized, but there seems to be room for further improvement. The technique disclosed in Patent Document 1 does not consider a case where there are a plurality of objects. In order to further reduce the power consumption in the sleep mode, it is necessary to consider how to drive a plurality of sensors.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an image forming apparatus with low power consumption in an image forming apparatus having a plurality of sensors that are triggers for returning from a sleep mode.

  The image forming apparatus according to the present invention takes one of a sleep mode and a normal operation mode that shift when the unused state continues for a predetermined time or more, and a trigger for transition from the sleep mode to the normal operation mode. In the sleep mode, the first and second detection means for detecting the event respectively, the first and second power supply means for supplying power to the first and second detection means, respectively, Timing control means for periodically controlling the first and second power supply means at regular intervals so that the periods for supplying power to the first and second detection means do not overlap each other.

  When the first and second detection means detect an event that triggers the transition from the sleep mode to the normal operation mode, the first and second detection means transmit a signal to notify the mode transition. The image forming apparatus receives this signal only for one detection means at a time. Therefore, the first and second detection units do not need to operate simultaneously, and it is useless to always supply power to both detection units. In the image forming apparatus according to the present embodiment, the periods for supplying power to the first and second detection units do not overlap. Therefore, power consumption can be reduced as compared with the case where power is always supplied to both detection means.

  Preferably, the length of the power supply period to the first and second detection means by the timing control means is equal to each other.

  Since the lengths of the power supply periods to the first and second detection means are equal, both detection means can be operated under the same conditions.

  Preferably, the length of the power supply period to the first and second detection means by the timing control means is different from each other.

  Depending on the length of the power supply period to the first and second detection means, the power supply period of the detection means that may be frequently used is set longer, etc. Accordingly, it is possible to further reduce the power consumption while reducing the risk of the detection failure of the event that triggers the transition to the normal operation mode.

  Preferably, the frequency of the power supply period to the first and second detection means by the timing control means is equal to each other within the cycle.

  Since the frequency of the power supply period to the first and second detection means is equal, both detection means can be operated under the same conditions.

  Preferably, the frequency of power supply to the first and second detection means by the timing control means is different from each other within the period.

  Since the frequency of the power supply period to the first and second detection means is different, the detection means that may be frequently used is set so that the frequency of the power supply period is increased. Depending on conditions, it is possible to reduce power consumption while reducing the risk of detection failure of an event that triggers the transition to the normal operation mode.

  Preferably, the image forming apparatus according to the present invention includes storage means for storing order information indicating an order of supplying power to the first and second detection means within a cycle, and the timing control means includes the storage means In accordance with the order stored in the first and second detection means, power is periodically supplied to the first and second detection means.

  The image forming apparatus causes the first and second detection units to supply power in accordance with the order information stored by the storage unit. For this reason, if the order information is programmed in advance in the storage means, the image forming apparatus operates the detection means in accordance with the programmed order information. The detection means can be easily operated in a desired order while reducing power consumption.

  More preferably, the storage means further stores power supply availability information indicating whether or not to supply power to the first and second detection means. The timing control means determines whether to supply power to the first and second detection means within a cycle according to the power supply availability information stored in the storage means.

  By determining the power supply to the first and second detection means according to the power supply availability information, it is determined whether or not power is supplied to each detection means. It is possible to dispense with power supply to the detection means that does not need to be activated. As a result, power consumption can be reduced.

  More preferably, the storage means further stores a period length per cycle when power is supplied to the first and second detection means, and the timing control means stores the period length stored in the storage means. Accordingly, a period for supplying power per cycle to the first and second detection means is determined.

  The power supply to the detection means is determined by the stored power supply availability information and the period length. Therefore, if the power supply availability information and the period length are set in advance, the power supply to the first and second detection means can be set as desired by the user. As a result, it is possible to reduce the power consumption while making a setting to reduce the risk of occurrence of an omission of detection of an event that triggers the transition to the normal operation mode.

  Preferably, the image forming apparatus according to the present invention further includes a setting unit used by the user to set information stored in the storage unit.

  The user can arbitrarily set information included in the storage means. Therefore, in the sleep mode, the user can set as desired a setting that reduces the risk of missing detection of an event that triggers the transition to the normal operation mode, and at the same time, it is possible to reduce power consumption.

  According to the present invention, the power consumption of the image forming apparatus in the sleep mode can be reduced.

1 is a perspective view showing an external appearance of a multifunction machine that is an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a perspective view showing an open / close state of an automatic document processing apparatus 112 of the multifunction machine shown in FIG. 1. FIG. 3 is a partial cross-sectional view illustrating an internal configuration of the image forming apparatus illustrated in FIGS. 1 and 2. FIG. 4 is an enlarged view of an image station in the multifunction peripheral shown in FIG. 3. FIG. 2 is a diagram illustrating an example of a control block of the multifunction peripheral illustrated in FIG. 1. It is a figure which shows an example of the electric power supply of each sensor power supply by which duty control is carried out. It is a figure which shows the example which changed the power-on time of duty control for every sensor. It is a figure which shows the example which changed the power-on frequency | count of duty control for every sensor. It is a figure which shows the example which changed the power-on time per unit time of duty control, and the power-on frequency | count for every sensor. It is a setting screen displayed in order to set the use frequency level of each function part. FIG. 2 is a diagram illustrating an example of a control block of the multifunction peripheral illustrated in FIG. 1. It is an example of the matrix table | surface which shows the setting state of the duty control of each sensor. It is a figure which shows the example which the user changed arbitrarily the power-on time of duty control. It is a setting screen displayed in order for a user to arbitrarily set execution of duty control. It is an example of the matrix table | surface which shows the setting state of the duty control of each sensor. It is a matrix table which associates the combination of ON / OFF setting of each sensor, and i value. It is an example of the table | surface which shows the order of the duty control derived | led-out from i value. It is a figure which shows the example which the user arbitrarily set execution of duty control. It is a figure which shows the difference in the power consumption by the case where duty control is performed and it is not performed.

  In the following description and drawings, the same parts are denoted by the same reference numerals. Their functions and names are also the same. Therefore, detailed description thereof will not be repeated.

  In the following description and drawings, the image forming apparatus according to the embodiment of the present invention will be described as a tandem full-color type multifunction peripheral (MFP (Multifunction Peripheral)). However, the present invention is not limited to such. The image forming apparatus may be a full color type of another type (for example, 4 cycles) or a monochrome type.

<< First Embodiment >>
[Image forming apparatus (hardware)]
The image forming apparatus according to the first embodiment of the present invention is a so-called multi-function peripheral (MFP), and has a copy function (copy mode), a facsimile transmission / reception function (facsimile mode), and a printer function (printer mode) as operation modes. And a scanner function (scanner mode).

  In the following, particularly with reference to FIGS. 1 to 4, internal configuration of MFP 100 according to the present embodiment in relation to a function of forming an image on recording paper (used in copy mode, facsimile reception mode, and printer mode) An outline of the operation will be described. In this specification, “copy” refers to a process of printing on a recording sheet based on image data obtained by scanning a document. “Image formation” is not limited to copying, but also refers to a process of printing an image received by facsimile on a recording sheet or printing image data received from a printer on a recording sheet.

  MFP 100 forms a multicolor image or a single color image on a predetermined recording sheet based on image data received from an information processing apparatus such as a computer via a network line or scan data of a document scanned by MFP 100. To do.

  Referring to FIGS. 1 and 2, MFP 100 generally includes a main body 110, an automatic document processing apparatus 112 provided on the upper portion of main body 110, and details are not shown in FIG. And an image forming unit 114 and a recording paper transport unit 116 provided inside the main body 110. A manual paper feed cassette 190 is provided on the right side surface of the main body 110. The automatic document processor 112 is used in a copy mode or a scanner mode. As shown in FIG. 2, a document placement table 148 made of transparent glass on which a document is placed is provided on the upper surface of the main body 110.

  The automatic document processor 112 is attached to the main body 110 so as to cover the document table 148. The automatic document processor 112 automatically conveys the document on the document table 148. Further, as shown in FIG. 2, the automatic document processor 112 is attached to the main body 110 so as to be rotatable in the direction of the arrow M, and can open the top of the document table 148. When the document table 148 is opened, the document can be manually placed on the document table 148.

  An operation device 240 that receives an operation by a user and outputs an operation signal is provided on the upper front surface of the main body 110 of the MFP 100. The operation device 240 includes a plate-like operation unit 242 having a hardware key including a numeric keypad and other various operation buttons, which is disposed in a region on the right side of the surface of the operation device 240, and a left side of the surface of the operation device 240. And a display unit 244 which is a small touch panel integrated liquid crystal display device disposed in the area. The operation unit 242 and the display unit 244 are held in one housing, and the operation device 240 is integrated as a whole. The display unit 244 can display information based on a display signal given from the outside.

  On the display unit 244 of the operation device 240, an operation state of the MFP 100, a menu for the user to select a desired function, and the like are displayed. A selection button or the like is displayed on the display area of the display unit 244. When the user presses the displayed area such as the selection button with a finger, the touch panel of the display unit 244 detects the pressed position. The user's instruction is detected by comparing the display position of the selection button with the position where the touch panel is pressed on the program. In accordance with the detected user instruction, function setting and operation of MFP 100 are performed.

  Referring to FIG. 3, a document reading unit 118 that reads a document placed on document placing table 148 and outputs it as image data is provided in the upper part of main body 110 and directly below document placing table 148.

  Various units constituting the image forming unit are arranged inside the main body 110. Each of the image forming units 114 includes a photoconductor drum, and four image stations for forming four images of black (K), cyan (C), magenta (M), and yellow (Y) on the photoconductor. 150, 152, 154, and 156, an exposure unit 130 that forms a latent image of each color image on the surface of the photosensitive drum in each of the image stations 150, 152, 154, and 156 based on the image data; 152, 154 and 156 are arranged above the intermediate transfer belt unit 140 for transferring the images of the respective colors formed on these sheets onto the recording paper, and for fixing the image transferred onto the recording paper. A fixing unit 142.

  The image data handled in the MFP 100 is data representing a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y). Each of the image stations 150, 152, 154, and 156 is for forming four types of latent images corresponding to these four colors. These have the same configuration. Referring to FIG. 4, for example, an image station 156 is provided on the surface of the photosensitive drum 134 on which a latent image based on image data is formed, and is provided close to the surface of the photosensitive drum 134. A charger 138 for uniformly charging to a predetermined potential, a developer 132 for developing a latent image formed on the surface of the photosensitive drum 134 with toner, and a visible image on the surface of the photosensitive drum 134 A cleaner unit 136 for removing and collecting toner remaining on the surface of the photosensitive drum 134 after being transferred to an intermediate transfer belt described later is included.

  The exposure unit 130 is a laser scanning unit (LSU: Laser Scanning Unit) that includes a laser emitting portion, a reflection mirror, and the like. The exposure unit 130 includes a polygon mirror that scans laser light corresponding to each color emitted by the laser emitting unit, a lens that guides the laser light of each color reflected by the polygon mirror to the photosensitive drum 134 of each image station, and Optical elements such as mirrors.

  The exposure unit 130 exposes the charged photosensitive drum 134 of each image station according to each color of the input image data. As a result, an electrostatic latent image corresponding to the image data of each color is formed on the surface of the photosensitive drum 134 of each image station.

  An intermediate transfer belt unit 140 is disposed above the photosensitive drum 134. The intermediate transfer belt unit 140 includes an intermediate transfer belt 160, an intermediate transfer belt driving roller 162, an intermediate transfer belt driven roller 164, four intermediate transfer rollers 166 provided for each of C, M, Y, and K, and An intermediate transfer belt cleaning unit 168 is included. The intermediate transfer belt driving roller 162, the intermediate transfer belt driven roller 164, and the intermediate transfer roller 166 stretch and drive the intermediate transfer belt 160. The intermediate transfer roller 166 provides a transfer bias for transferring the toner image on the photosensitive drum 134 onto the intermediate transfer belt 160.

  The intermediate transfer belt 160 is provided so as to be in contact with the four photosensitive drums 134, and sequentially transfers the toner images of the respective colors formed on the photosensitive drum 134 onto the intermediate transfer belt 160. A color toner image (multicolor toner image) is formed on the intermediate transfer belt 160. The intermediate transfer belt 160 is formed in an endless shape using, for example, a film having a thickness of about 100 μm to 150 μm.

  The toner image is transferred from the photosensitive drum 134 to the intermediate transfer belt 160 by an intermediate transfer roller 166 that is in contact with the back side of the intermediate transfer belt 160. The intermediate transfer roller 166 is applied with a high-voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) in order to transfer the toner image. The intermediate transfer roller 166 is a roller that is based on a metal (for example, stainless steel) shaft having a diameter of 8 mm to 10 mm and whose surface is covered with a conductive elastic material (for example, ethylene-propylene-diene rubber, urethane foam, or the like). By this conductive elastic material, a high voltage can be uniformly applied to the intermediate transfer belt 160. In this embodiment, a roller-shaped electrode is used as the transfer electrode, but a brush-shaped electrode or the like can be used in addition to that.

  As described above, the electrostatic latent images visualized according to the respective colors on the respective photosensitive drums 134 are stacked on the intermediate transfer belt 160. The laminated image information is transferred onto the recording sheet by a later-described transfer roller 180 disposed at a contact position between the recording sheet and the intermediate transfer belt 160 by the rotation of the intermediate transfer belt 160.

  At this time, the intermediate transfer belt 160 and the transfer roller 180 are pressed against each other at a predetermined nip, and a voltage for transferring the toner to the recording paper is applied to the transfer roller 180. This voltage is a high voltage having a polarity (+) opposite to the charging polarity (−) of the toner. In order to constantly obtain the nip, either the transfer roller 180 or the intermediate transfer belt driving roller 162 is formed of a hard material (metal or the like), and the other is formed of a soft material such as an elastic roller. Examples of the soft material include elastic rubber and foamable resin.

  The toner that is not transferred onto the recording paper and remains on the intermediate transfer belt 160 causes toner color mixing in the next step. Such toner is removed and collected by the intermediate transfer belt cleaning unit 168. The intermediate transfer belt cleaning unit 168 has a cleaning blade that contacts the intermediate transfer belt 160. At the position where the cleaning blade comes into contact, the intermediate transfer belt 160 is supported by the intermediate transfer belt driven roller 164 from the back side.

  In addition to the above-described manual paper feed cassette 190, the recording paper transport unit 116 and the paper feed cassette 144 provided at the lower part of the main body and the original on the upper part of the main body part 110 where the recording paper after the image is formed are discharged. And a paper discharge tray 146 provided below the mounting table 148.

  The paper feed cassette 144 is a tray for storing recording paper used for image formation, and is provided below the exposure unit 130 of the main body 110. A recording sheet used for image formation can also be placed on the manual sheet feeding cassette 190. The paper discharge tray 146 is a tray for collecting printed recording sheets face down.

  The recording paper transport unit 116 is formed inside the main body 110 and is used to send the recording papers of the paper feed cassette 144 and the manual paper feed cassette 190 to the paper discharge tray 146 via the transfer roller 180 and the fixing unit 142. , Including a substantially vertical sheet conveyance path 120. The recording paper conveyance unit 116 is further provided with a pickup roller 200, a pickup roller 202, and a plurality of conveyance rollers 204-provided in the vicinity of the paper conveyance path 120 from the paper feed cassette 144 or the manual paper feed cassette 190 to the paper discharge tray 146. A conveyance roller 210, a registration roller 212, a transfer roller 180, a fixing unit 142, and the like are included.

  The conveyance rollers 204 to 210 are small rollers for promoting and assisting the conveyance of the recording paper, and a plurality of conveyance rollers 204 to 210 are provided along the paper conveyance path 120. The pickup roller 200 is provided near the end of the paper feed cassette 144 and picks up recording paper from the paper feed cassette 144 one by one and supplies it to the paper transport path 120. Similarly, the pickup roller 202 is provided in the vicinity of the end of the manual paper feed cassette 190 and picks up the recording paper one by one from the manual paper feed cassette 190 and supplies it to the paper transport path 120.

  The registration roller 212 temporarily holds the recording paper conveyed through the paper conveyance path 120. The registration roller 212 conveys the recording paper to the transfer roller 180 at a timing when the leading edge of the toner image on the photosensitive drum 134 is aligned with the leading edge of the recording paper.

  The fixing unit 142 includes a heat roller 220 and a pressure roller 222. The heat roller 220 and the pressure roller 222 are arranged and rotated with a recording sheet interposed therebetween. The heat roller 220 is set to have a predetermined fixing temperature based on a signal from a temperature detector (not shown). The pressure roller 222 and the heat roller 220 are used to thermally press the toner onto the recording paper, so that the multicolor toner image transferred onto the recording paper is melted, mixed and pressed to be fixed on the recording paper.

  Although not shown, the fixing unit 142 is provided with a heater such as a halogen heater for heating the heat roller 220.

  The recording paper conveyance path is as follows. As described above, the MFP 100 is provided with the paper feed cassette 144 and the manual paper feed cassette 190 that store recording paper in advance. In order to feed recording paper from these paper feed cassette 144 or manual paper feed cassette 190, a pickup roller 200 or pickup roller 202 is arranged to guide the recording paper to the paper transport path 120 one by one. .

  A recording sheet conveyed from the sheet feeding cassette 144 or the manual sheet feeding cassette 190 is conveyed to the registration roller 212 by the conveying roller 204 in the sheet conveying path 120. The recording sheet is conveyed to the transfer roller 180 at a timing when the leading end of the sheet and the leading end of the image information on the intermediate transfer belt 160 are aligned, and the image is transferred from the intermediate transfer belt 160 onto the recording sheet. Thereafter, when the recording paper passes through the fixing unit 142, the unfixed toner on the recording paper is melted and fixed by heat. Further, the recording paper is discharged onto a paper discharge tray 146 through a conveyance roller 206 disposed thereafter.

  The conveyance path is when an image is formed on one side of the recording paper. On the other hand, when images are formed on both sides of a recording sheet, the recording sheet is conveyed on a conveyance path described below. As described above, image formation on one side is completed, and the recording paper passes through the fixing unit 142. When the trailing edge of the recording sheet is gripped by the final transport roller 206, the transport roller 206 rotates in the reverse direction. As a result, the recording sheet is guided to the conveyance rollers 208 and 210. Thereafter, the recording paper is conveyed to the transfer roller 180 through the registration roller 212. Here, as in the case of forming an image on one side, an image is formed on the back side of the recording paper. Thereafter, the recording paper is discharged to a paper discharge tray 146.

  Such control of the recording paper transport process is executed by a control unit that controls the recording paper transport unit.

[action mode]
MFP 100 according to the present embodiment includes a copy mode, a facsimile transmission / reception mode, a printer mode, and a scanner mode as its operation modes. In the following, these operation modes will be described. In the example of the screen displayed on the display unit 244, the facsimile transmission / reception mode and the scanner mode are described as a “fax / image transmission” mode and a “document filing” mode, respectively.

-Copy mode-
In the following, the operation of the copy mode will be described. In this copy mode, the copy function is realized mainly by the operation of the main body 110. When the document is automatically fed, the automatic document processor 112 operates.

  A document placed on the document table 148 is read by the document reading unit 118 as image data. This image data is input to the control unit, where various image processing is performed on the image data. An image forming unit having the above-described configuration prints an image of a document indicated by the image data on a recording sheet.

-Facsimile mode-
In the facsimile mode, the transmission operation is mainly realized by operating the document reading unit 118 and the FAX communication unit. The reception operation is realized by the operation of the FAX communication unit and the image forming unit.

  During transmission, MFP 100 operates as follows. In MFP 100, a facsimile mode is designated. A document placed on the document table 148 is read as image data by the document reading unit 118. The read image data is input to the control unit, where various image processing is performed on the image data. This image data is output to the FAX communication unit. The FAX communication unit connects the designated transmission line to the designated transmission destination, converts the image data into communication data conforming to the facsimile communication standard, and transmits the communication data to the reception side facsimile apparatus. When the line is connected, the receiving facsimile apparatus detects a communication request signal from the FAX communication unit of MFP 100 and transmits a response signal. After that, for example, the FAX communication unit of the MFP 100 and the facsimile machine on the receiving side deliver the capability information mounted on each other, and determine the communication speed at the maximum available capability and the encoding / code correction method of the image data. To set the modem communication method. Image data is transmitted from the FAX communication unit of MFP 100 to the receiving facsimile apparatus using an image signal format adapted to this communication method. When transmission is completed, the line is disconnected.

  The receiving operation is as follows. The FAX communication unit of MFP 100 on the receiving side converts the received data into image data and sends it to the image forming unit. The received data may be converted into image data by the image forming unit. The image forming unit forms an image on the recording paper based on the image data obtained by conversion from the received data, as in the operation in the copy mode described above.

-Printer mode-
In this printer mode, the printer function is realized mainly by the operation of the image forming unit.

  When MFP 100 receives print data from a computer via a network interface (not shown), the received print data is sent to the image forming unit. The image forming unit converts this print data into image data. The image forming unit forms an image on a recording sheet based on image data obtained by conversion from print data, as in the above-described operation in the copy mode.

-Scanner mode-
In the scanner mode, the scanner function is realized mainly by the operation of the document reading unit 118.

  A document placed on the document table 148 is read as image data by the document reading unit 118. The read image data is input to the control unit, where various image processing is performed on the image data. This image data is stored in a storage device (hard disk) (not shown) of MFP 100, transmitted to a computer connected to a network via a network interface, or transmitted as an attached file of an e-mail via a network interface. In this specification, these operation modes are referred to as “document filing”, “scan to folder”, and “scan to mail”, respectively.

[Control block structure]
Referring to FIG. 5, the control block of MFP 100 includes the following functional blocks. MFP 100 has functional blocks that realize general functions as an image forming apparatus. However, since these functional blocks are not directly related to the features of the present embodiment, the details thereof will not be described here.

  Referring to FIG. 5, the control block of MFP 100 includes an automatic document processing device 112, an image forming unit 114, a recording paper transport unit 116, and an operation device 240 based on the output of the operation device 240 in addition to the operation device 240 described above. And a first sensor 312 that generates a trigger signal for returning from the sleep mode to the normal operation mode by detecting the occurrence of an event such as a user operation during the sleep mode. The second sensor 314, the third sensor 316, and the main controller 300 are connected to the main controller 300, and the first to third sensors 312, 314, 316 are performing duty control while there is an output from these sensors. And a controller 302 for supplying a return trigger signal to the main control unit 300. The controller 302 includes sensor power supply units 304, 306, and 308 for turning on / off power supply from the power supply 318 to the sensors 312, 314, and 316, respectively, and sensor power supply units 304, 306, and 308 in the sleep mode. And a sub-control unit 310 for performing duty control. The sub-control unit 310 performs the duty control, and at the same time, determines whether there is a trigger signal from the first to third sensors 312, 314, and 316 that indicates that the user has operated each function unit. Is detected.

  MFP 100 returns to the normal operation mode when the user operates one of the functional units in the sleep mode. The first to third sensors detect such an operation instruction from the user and output a signal notifying the detection to the sub-control unit 310. For this reason, the first to third sensors 312, 314, and 316 are installed in functional units that the user may operate. For example, the automatic document processing device 112, the paper feed cassette 144, the document placement table 148, the manual paper feed cassette 190, and the operation device 240 including the operation unit 242 and the display unit 244 may be used. The first to third sensors may be installed in an opening / closing cover (not shown) included in the image forming unit 114, the recording paper transport unit 116, and the like. The opening / closing cover is frequently used when a user performs a paper jam removing operation and a replacement operation of consumables such as ink, toner, and a photoreceptor. Not only this embodiment but this specification WHEREIN: Each sensor shall be installed in such a function part.

  The sub-control unit 310 includes, for example, an ASIC (Application Specific Integrated Circuit). An ASIC has a higher operation speed and lower power consumption than other single semiconductors. The sub control unit needs to quickly send a signal for switching the MFP 100 from the sleep mode to the normal operation mode to the main control unit 300 in accordance with the signal from each sensor. Therefore, the ASIC is suitable for the sub control unit 310.

[Operation]
The operation of MFP 100 based on the above structure will be described with reference to FIGS. In response to the elapse of a predetermined time from when MFP 100 was last operated, main control unit 300 provides a signal indicating that MFP 100 is switched to the sleep mode to sub control unit 310, and then to each unit of MFP 100. Is turned off and the MFP 100 is switched to the sleep mode. In response to this signal, the sub-control unit 310 starts the following duty control for the sensor power supply units 304, 306, and 308.

  Referring to FIG. 6, first, sub-control unit 310 turns on the first sensor for a time T1, and turns off the second and third sensors. The sub-control unit 310 reads the output of the first sensor at a predetermined timing during this time T1, and if it is High, outputs a trigger signal to the main control unit. When the time T1 has passed, the sub-control unit 310 turns off the first sensor and turns on the second sensor for the time T1. At a predetermined timing during this time, the sub control unit 310 reads the output of the second sensor. If it is High, the sub-control unit 310 outputs a trigger signal to the main control unit 300. When the time T1 has passed, the sub-control unit 310 turns off the second sensor, and this time turns on the third sensor. The sub-control unit 310 reads the output of the third sensor at a predetermined timing within the time T1, and outputs a trigger signal to the main control unit 300 if it is High. When the time T1 has passed, the sub-control unit turns off the third sensor and returns to the beginning to turn on the first sensor.

  Thereafter, the sub-control unit repeats such an operation at a constant cycle. When the user operates a component provided with any sensor in the sleep mode, an appropriate one of the first to third sensors detects it, and time T1 allocated to that sensor in the above-described repetition. Among them, a high output is given to the sub-control unit 310. The sub-control unit 310 gives a trigger signal to the main control unit 300 in response to the output of the sensor being High. In response to the trigger signal, main control unit 300 resumes power supply to each unit of MFP 100 and returns MFP 100 to the normal operation mode.

  Normally, the sub-control unit 310 can only read the output of one sensor at a time. Even if a plurality of sensors are turned on and operating at the same time, the outputs of these sensors cannot be read simultaneously by the sub-control unit. It is sufficient that only the sensor to be read is operating, and it is not always necessary to supply power to the sensor that is not to be read. By performing duty control as in the present embodiment, the power consumption of MFP 100 in the sleep mode can be reduced.

<< Second Embodiment >>
The image forming apparatus according to the second embodiment differs from the image forming apparatus according to the first embodiment only in the point of duty control for each sensor power supply unit. In other respects, the basic configuration and operation of the image forming apparatus according to the second embodiment of the present invention are the same as those of the first embodiment. Therefore, detailed description thereof will not be repeated. This is not limited to this embodiment, and the same applies to other embodiments described below.

[Control block structure]
The sub-control unit (not shown, corresponding to the sub-control unit 310 in FIG. 4) according to the present embodiment sets the power-on time of the corresponding sensor power unit according to the frequency of detecting the output of each sensor. adjust. The detection frequency of the sensor output is determined depending on which part is likely to be operated by the user. Referring to FIG. 7, in this embodiment, the second sensor has the highest output detection frequency, and the sensor output detection frequency decreases in the order of the first sensor and the third sensor. In this case, in the present embodiment, the length of the power-on time of each sensor indicated by T1, T2, and T3 in the figure is set to satisfy T2>T1> T3. That is, the length of the power-on time corresponds to the frequency of detecting the output of each sensor. In this way, when a function unit that is frequently used is operated, the sub-control unit can quickly detect the sensor output and can immediately output a trigger signal for returning to the normal operation mode.

[Operation]
Referring to FIG. 7, when entering the sleep mode, the sub-control unit operates as follows. The sub-control unit first turns on the first sensor for a time T1, and reads the output of the first sensor during this time. If the output of the first sensor is High, the sub control unit outputs a trigger signal to the main control unit. If the output of the first sensor is Low, the sub control unit does not output a trigger signal. When time T1 has passed, the sub-control unit turns off the first sensor and turns on the second sensor. The sub control unit reads the output of the second sensor during time T2, and if it is High, outputs a trigger signal to the main control unit. If it is Low, the second sensor is turned on until the time T2 passes, then the second sensor is turned off and the third sensor is turned on. The sub-control unit reads the output of the third sensor during time T3, and outputs a trigger signal to the main control unit if High. If it is Low, the sub-control unit turns off the third sensor after the time T3 has elapsed. Returning to the beginning, the sub-control unit turns on the first sensor and reads the output of the first sensor during time T1.

  Hereinafter, such control is repeated at a constant cycle. If the output of the first, second, or third sensor becomes High during the sleep mode, the sub control unit outputs a trigger signal to the main control unit. In response to the trigger signal, the main control unit returns the image forming apparatus to the normal operation mode.

  In the present embodiment, as in the first embodiment, only one sensor is operating at a time. Compared with the case where three sensors are always operated, power consumption can be reduced. Further, in the present embodiment, the time during which each sensor is on is adjusted according to the frequency of use of the portion where the sensors are provided. Therefore, there is an effect that the possibility that the user's operation can be detected in a timely manner and quickly returned to the normal operation mode can be increased.

<< Third Embodiment >>
[Control block structure]
The sub-control unit (not shown, corresponding to the sub-control unit 310 in FIG. 4) according to the present embodiment determines the number of times the corresponding sensor power unit is turned on according to the frequency of detecting the output of each sensor. adjust. The detection frequency of the sensor output is determined by which part is likely to be operated by the user. Referring to FIG. 8, in the present embodiment, the second sensor has the highest output detection frequency, and the first sensor and the third sensor have the same output detection frequency. In this case, in the present embodiment, the number of times of power-on of each sensor is the highest for the second sensor, and the same number of times for the first sensor and the third sensor. That is, the number of power-on times corresponds to the frequency of detecting the output of each sensor. In this way, when a function unit that is frequently used is operated, the sub-control unit can quickly detect the sensor output and can immediately output a trigger signal for returning to the normal operation mode.

[Operation]
Referring to FIG. 8, when the sleep mode is entered, the sub control unit operates as follows. The sub-control unit first turns on the first sensor for a time T1, and reads the output of the first sensor during this time. If the output of the first sensor is High, the sub control unit outputs a trigger signal to the main control unit. If the first sensor is Low, the sub control unit does not output a trigger signal. When time T1 has passed, the sub-control unit turns off the first sensor and turns on the second sensor. The sub-control unit reads the output of the second sensor, and if it is High, outputs a trigger signal to the main control unit. If it is Low, the second sensor is turned on until the time T1 passes, then the second sensor is turned off and the third sensor is turned on. The sub control unit reads the output of the third sensor, and if it is High, outputs a trigger signal to the main control unit. If it is Low, the third sensor is turned off and the second sensor is turned on again after the time T1 has elapsed. The sub control unit reads the output of the second sensor, and if it is High, outputs a trigger signal to the main control unit. If it is Low, the sub-control unit turns on the second sensor until time T1 passes, then turns off the second sensor, and turns on the first sensor again.

  Hereinafter, such control is repeated at a constant cycle. If the output of the first, second, or third sensor becomes High during the sleep mode, the sub control unit outputs a trigger signal to the main control unit. In response to the trigger signal, the main control unit returns the image forming apparatus to the normal operation mode.

  In the present embodiment, as in the first and second embodiments, only one sensor is operating at a time. Compared with the case where three sensors are always operated, the power consumption of the image forming apparatus can be reduced. Further, in this embodiment, the time during which the sensors are turned on is set to the length of time T1 at a time, and the order in which the sensors are turned on is adjusted according to the number of times each sensor is turned on. The number of times is adjusted according to the frequency of use of the portion where the sensor is provided. Therefore, there is an effect that the possibility that the user's operation can be detected in a timely manner and quickly returned to the normal operation mode can be increased.

<< Fourth Embodiment >>
[Control block structure]
The sub-control unit (not shown, corresponding to the sub-control unit 310 in FIG. 4) according to the present embodiment, depending on the frequency of detecting the output of each sensor, Adjust the number of times the power is turned on. The detection frequency of the sensor output is determined depending on which part is likely to be operated by the user.

  Referring to FIG. 9, in the present embodiment, the second sensor has the highest output detection frequency, and then the first sensor is followed by the third sensor. The length of the power-on time of each sensor indicated by T1, T2, and T3 in the figure is set so that T2> T1> T3. That is, the length of the power-on time corresponds to the frequency of detecting the output of each sensor.

  Referring to FIG. 9, the number of power-on times is the highest for the second sensor and the same number for the first and third sensors. In other words, in the present embodiment, the sensor having the highest frequency of detecting the output is set to have the highest power-on count.

  By setting the power-on time and the number of power-on times as described above, when a frequently used function unit is operated, the sub-control unit can quickly detect the sensor output and immediately send a trigger signal for returning to the normal operation mode. It can be detected.

[Operation]
Referring to FIG. 9, when the sleep mode is entered, the sub control unit operates as follows. The sub-control unit first turns on the first sensor for a time T1, and reads the output of the first sensor during this time. If the output of the first sensor is High, the sub control unit outputs a trigger signal to the main control unit. If the output of the first sensor is Low, the sub control unit does not output a trigger signal. When time T1 has passed, the sub-control unit turns off the first sensor and turns on the second sensor. The sub-control unit reads the output of the second sensor during time T2, and outputs a trigger signal to the main control unit if High. If it is Low, the second sensor is turned on until the time T2 passes, then the second sensor is turned off and the third sensor is turned on. During the time T3, the output of the third sensor is read, and if it is High, a trigger signal is output to the main controller. If it is Low, the third sensor is turned on until time T3 passes, then the third sensor is turned off and the second sensor is turned on again. During the time T2, the output of the second sensor is read, and if it is High, a trigger signal is output to the main controller. If it is Low, after the time T2 has elapsed, the sub-control unit turns off the second sensor. Returning to the beginning, the sub-control unit turns on the first sensor and reads the output of the first sensor during time T1.

  Hereinafter, such control is repeated at a constant cycle. If the output of the first, second, or third sensor becomes High during the sleep mode, the sub control unit outputs a trigger signal to the main control unit. In response to the trigger signal, the main control unit returns the image forming apparatus to the normal operation mode.

  In the present embodiment, as in the first to third embodiments, only one sensor operates at a time. Compared with the case where three sensors are always operated, the power consumption of the image forming apparatus can be reduced. In the present embodiment, the number of power-on times and the power-on time of each sensor are adjusted according to the frequency of use of the portion where the sensor is provided. Therefore, there is an effect that the possibility that the user's operation can be detected in a timely manner and quickly returned to the normal operation mode becomes higher than in the first to third embodiments.

<< Fifth Embodiment >>
[Duty control setting]
In the present embodiment, the user can arbitrarily set to which sensor how much power is supplied to each sensor. Referring to FIG. 10, when a predetermined operation is performed on operation unit 242 or display unit 244 shown in FIG. 1, what kind of duty control is performed on each sensor on display unit 244. A setting screen 400 for setting is displayed. On the setting screen 400, an allowable value display unit 370 that indicates an allowable value of power that can be supplied to the sensor in the sleep mode, a name display unit 380 that displays the name of each functional unit in which each sensor is installed, and duty control are displayed. A control display unit 390 for selecting whether or not to be performed, a usage frequency setting unit 410 for setting the usage frequency of each functional unit displayed on the name display unit 380, and how much power is supplied to each sensor. A power consumption display unit 420 for displaying whether or not, and a power consumption total display unit 430 for displaying the total power consumption of the sensor are displayed. When the user touches the display location of the functional unit that is displayed on the usage frequency setting unit 410 and the usage frequency setting is to be switched, the usage frequency level of the functional unit is in the order of low, medium, and high according to the number of touches. Switch. As the usage frequency level is switched, the power value displayed on the power consumption display unit 420 of the function unit is also switched. Furthermore, the total power consumption value of the entire sensor displayed on the total power consumption display unit 430 is also switched according to the switching of the power value. Settings displayed on the setting screen 400 are stored, and duty control based on the settings is performed in the sleep mode.

  The user can set the usage frequency level for each functional unit while referring to the allowable value display unit 370, the power consumption display unit 420, the total power consumption display unit 430, and the like on the setting screen 400. For example, when the power consumption of the MFP 100 is 2 watts or less, the power consumption of each sensor displayed on the power consumption display unit 420 is displayed with a power value such that the total of each sensor does not exceed 2 watts. The power value is set in consideration of the display level of the usage frequency displayed on the usage frequency setting unit 410. When the total power consumption of each sensor may exceed the allowable value displayed on the allowable value display unit 370, a warning screen (not shown) that prompts the user to change the setting is displayed on the setting screen 400. Is displayed.

[Control block structure]
The structure of the control block according to the present embodiment is basically the same as the structure of the control block according to the first to fourth embodiments. However, the number of sensor power supply units and sensors that perform duty control, and the functions related to duty control of the sub-control unit are different. Referring to FIG. 11, in the present embodiment, controller 302 includes sensor power supply units 352-356 and first power supply units 352-356 in addition to sensor power supply units 304-308 and first to third sensors 312-316. 4 sensor 358, fifth sensor 360, and sixth sensor 362. The controller 302 further includes a sub control unit 350. The sensor power supply units 352 to 356 and the fourth to sixth sensors 358 to 362 have the same functions as the sensor power supply units 304 to 308 and the first to third sensors 312 to 316, respectively.

  The sub-control unit 350 according to the present embodiment has a length of a period during which power is supplied to the corresponding sensor power supply unit according to the setting of the usage frequency of the functional unit displayed on the setting screen 400, that is, the sensor power supply unit. Adjust the power on time. Referring to FIG. 13, among the function units in which six sensors are installed, the function unit in which the second sensor is installed has the highest frequency of use, and the function unit in which the fifth sensor is installed next is used. The frequency is high. The frequency of use of the functional unit in which the first, third, and fourth sensors are installed is assumed to be equal. Since the function unit in which the sixth sensor is installed is set to off, power is not supplied to the sixth sensor. In this case, the length of the power-on time T1-T5 is T2> T5> T1 = T3 = T4. That is, the length of the power-on time corresponds to the order of use frequency of the functional units where the sensors are installed. A function unit that is frequently used is likely to be operated to promote a return from the sleep mode to the normal operation mode. In particular, since the frequency of use is set by the user himself, the possibility of being operated is higher than in the first to fourth embodiments. Therefore, as in the present embodiment, if the power-on time of a sensor installed in a frequently used function unit is lengthened, the sub control unit 350 can quickly detect a signal related to mode return.

[Operation]
The operation of MFP 100 based on the above structure will be described with reference to FIGS. The user operates the operation device 240 illustrated in FIG. 1 to display the setting screen 400 illustrated in FIG. On the name display unit 380 on the setting screen 400, names of some functional units constituting the MFP 100 are displayed. The user sets the usage frequency level of these functional units by touching the corresponding part of the usage frequency setting unit 410. By touching the same location multiple times, the user can switch the usage frequency level to either low, medium or high. The values displayed on the power consumption display unit 420 and the total power consumption display unit 430 are also switched according to the change in the usage frequency level.

  Referring to FIGS. 10 and 12, based on the settings displayed on control display unit 390 and usage frequency setting unit 410, sub control unit 350 creates the matrix table shown in FIG. This matrix table quantifies the settings displayed on the control display unit 390 and the usage frequency setting unit 410. The numerical values in the table vary depending on whether duty control is performed on each sensor and on which usage frequency level of each functional unit is set. The item “ON / OFF” described in the matrix table is based on the display on the control display unit 390. When ON is displayed on the control display unit 390, a value of “1” is displayed in the matrix table, and when OFF is displayed, a value of “0” is displayed. The item “cycle length” described in the matrix table is based on the setting of the use frequency setting unit 410. When the usage frequency setting unit 410 selects low, the matrix table has a value of “1”, when medium is selected, a value of “2”, and when high is selected, “3”. Each value is displayed.

  Referring to FIG. 13, when the sleep mode is entered, sub control unit 350 performs the following control based on the matrix table shown in FIG. The sub-control unit 350 does not supply power to the sixth sensor because the on / off value of the sixth sensor illustrated in FIG. 12 is “0”.

  The sub-control unit 350 first turns on the first sensor for a time T1, and reads the output of the first sensor during this time. If the output of the first sensor is High, the sub control unit 350 outputs a trigger signal to the main control unit. If the output of the first sensor is Low, the sub control unit 350 does not output a trigger signal. When the time T1 passes, the sub-control unit 350 turns off the first sensor and turns on the second sensor. The sub-control unit 350 reads the output of the second sensor during the time T2, and outputs a trigger signal to the main control unit if it is High. If it is Low, the second sensor is turned on until the time T2 passes, then the second sensor is turned off and the third sensor is turned on. The sub-control unit 350 reads the output of the third sensor during time T3, and outputs a trigger signal to the main control unit if High. If it is Low, the third sensor is turned on until the time T3 passes, then the third sensor is turned off and the fourth sensor is turned on. The sub-control unit 350 reads the output of the fourth sensor during the time T4, and outputs a trigger signal to the main control unit if High. If it is Low, the fourth sensor is turned on until the time T4 has passed, and then the fourth sensor is turned off and the fifth sensor is turned on. The sub-control unit 350 reads the output of the fifth sensor during time T5, and outputs a trigger signal to the main control unit if High. If it is Low, the fifth sensor is turned on until the time T5 has passed, and then the fifth sensor is turned off. Thereafter, the control returns to the control of the first sensor again, and thereafter the same procedure is repeated at a constant cycle.

  Comparing the lengths of the sensor power-on times T1 to T5 and assuming that the times T1, T3 and T4 are 1, the length T5 is 2 and the length T2 is 3. That is, the length of T1-T5 corresponds to the numerical value of the cycle length of each sensor in the matrix table shown in FIG. Therefore, when the usage frequency level of each functional unit is changed by the usage frequency setting unit 410 shown in FIG. 10, the length of the power-on time of each corresponding sensor changes. As described above, the sub control unit 350 detects the output state of each sensor at a constant cycle. Therefore, a sensor with a long power-on time is detected many times by the sub-control unit 350. If the usage frequency level is set to a high level for a function unit that is frequently used, the power-on time of the sensor set in the function unit becomes long, and the sub-control unit 350 can quickly detect the instruction operation from the user. Increases nature.

<< Sixth Embodiment >>
[Duty control setting]
In the present embodiment, the user can arbitrarily set whether or not to perform duty control on each sensor. The setting screen 400 shown in FIG. 14 is basically the same as that shown in FIG. However, the control display unit 390 and the usage frequency setting unit 410 are displayed on the setting screen 400 shown in FIG. 10, whereas the setting screen shown in FIG. 14 is used to set whether to perform duty control. A control setting unit 450 and a usage frequency display unit 460 for displaying the usage frequency level of each functional unit are displayed. The control setting unit 450 switches the duty control setting for the sensor to ON or OFF in response to a touch operation from the user. As the display of the control setting unit 450 is switched, the value of the total power consumption display unit 430 also changes. The user can set whether to perform duty control for each sensor while referring to the value of the total power consumption display unit 430.

[Control block structure]
The structure of the control block according to the present embodiment is basically the same as the structure of the control block according to the fifth embodiment. However, the functions relating to duty control of the sub-control unit (not shown, corresponding to the sub-control unit 350 of FIG. 11) are different.

  The sub control unit determines the matrix table shown in FIG. 15 based on the settings displayed on the setting screen 400 shown in FIG. This matrix table quantifies the settings displayed on the control setting unit 450 and the usage frequency display unit 460. The item “ON / OFF” described in the matrix table is based on the setting of the control setting unit 450, and the item of “Cycle ratio” is based on the display of the usage frequency display unit 460. The sub-control unit 470 determines in what order the power sources of the sensors are turned on based on the on / off value and the cycle ratio shown in FIG.

  Referring to FIG. 16, sub-control unit 470 determines an i value used to determine the power-on sequence from the on / off values shown in FIG. 15. FIG. 16 shows all combinations of on / off values of the sensors. The sub-control unit 470 calculates the i value in the setting from these combinations. For example, the combination of on / off values when duty control is performed only on the first sensor is (1, 0, 0, 0, 0, 0). The i value corresponding to this combination is i = 1 with reference to FIG. In the present embodiment, ON or OFF is selected for each of the six sensors. Accordingly, there are a total of 64 i values of 0-63. In the present embodiment, the usage frequency level of each functional unit is fixed regardless of the combination of on / off values.

[Operation]
The operation of MFP 100 based on the above structure will be described with reference to FIGS. The user operates the operation device 240 illustrated in FIG. 1 to display the setting screen 400 illustrated in FIG. The user touches a corresponding part of the control setting unit 450 to set whether or not to perform duty control on the sensor installed in the function unit displayed on the name display unit 380. The control setting unit 450 switches the display to ON or OFF according to the number of touches. By switching the setting of the control setting unit 450, the value displayed on the total power consumption display unit 430 changes. The user can operate the control setting unit 450 while referring to the allowable value display unit 370, the total power consumption display unit 430, and the like.

  Based on the settings made by the user, the sub-control unit creates a matrix table shown in FIG. The sub-control unit further determines the i value from FIG. 16 based on the matrix table.

  Referring to FIG. 17, the sub control unit determines the order in which each sensor is powered on from the above-described i value. The numerical values described in FIG. 17 indicate sensor numbers, and the sub-control unit turns on the power in order from the sensor with the sensor number described above. This order is programmed in advance in the sub-control unit based on the on / off value and cycle ratio shown in FIG. When the power-on time of the sensor with the sensor number indicated immediately above “End” ends, the sensor set at the beginning of the cycle is turned on again. Hereinafter, the sub-control unit repeats the duty control cycle.

  Referring to FIG. 18, the sub control unit performs duty control on each sensor based on the cycle ratio shown in FIG. 15 and the power-on sequence shown in FIG. Since the on / off value of the sixth sensor illustrated in FIG. 15 is “0”, power is not supplied to the sixth sensor.

  Referring to FIG. 18, when the sleep mode is entered, the sub control unit operates as follows. The sub-control unit first turns on the first sensor for a time T1, and reads the output of the first sensor during this time. If the output of the first sensor is High, the sub-control unit outputs a trigger signal to the main control unit, and does not output it if it is Low. When time T1 has passed, the sub-control unit turns off the first sensor and turns on the second sensor. The sub-control unit reads the output of the second sensor during time T1, and outputs a trigger signal to the main control unit if High. If it is Low, the second sensor is turned on until the time T1 passes, then the second sensor is turned off and the third sensor is turned on.

  In this way, the sub control unit turns on each sensor in a predetermined order, reads the output of the sensor, and outputs a trigger signal to the main control unit if it is High. In this way, as shown in FIG. 17, the sub-control unit performs the above-described operation in the order of the first, second, third, fifth, second, fourth, second, and fifth sensors. When the time T1 when the fifth sensor is turned on for the second time has passed, the procedure returns to the beginning.

  The sub-control unit performs duty control for each sensor, and at the same time, detects the sensor output for the sensor in the power-on state. In a state in which each sensor is duty-controlled, the sub-control unit detects more output states of the sensor with a large number of power-on times. Therefore, a sensor with a large number of power-on times is likely to be quickly detected by the sub-control unit.

  Referring to FIG. 17, the order in which duty control is performed is already programmed so as to be uniquely determined once i value is determined. However, in this embodiment, the user may arbitrarily set the order of duty control. Based on the settings of the control setting unit 450 and the usage frequency display unit 460, the order of duty control per cycle can be set.

  In the present embodiment, the user may be able to simultaneously set the duty control setting and the usage frequency level setting. In this case, since both the on / off value and the cycle ratio described in FIG. 15 change, variables other than the i value are set for determining the order in which the duty control is performed. It is conceivable to create a matrix table as shown.

  In any embodiment, the user may arbitrarily set the allowable value displayed on the allowable value display unit 370. The duty control is set in such a range that the total power consumption of the sensor does not exceed the allowable value. Therefore, if the user can arbitrarily set the allowable value, the power control desired by the user can be executed.

  In any embodiment, the number of sensors that perform duty control is not limited. Each sub-control unit performs duty control on three sensors in the first to fourth embodiments and six sensors in the fifth and sixth embodiments. However, these need not always be a fixed number. Therefore, when MFP 100 returns to the normal operation mode, it is possible to install sensors in all functional units that are considered to be operated by the user.

  The embodiment disclosed this time is merely an example, and the present invention is not limited to the embodiment described above. The scope of the present invention is indicated by each claim of the claims after taking into account the description of the detailed description of the invention, and all modifications within the meaning and scope equivalent to the wording described therein are included. Including.

100 MFP
240 Operation Device 242 Operation Unit 244 Display Unit 302 Controller 304-308, 352-356 Sensor Power Supply Unit 310, 350 Sub Control Unit 312 First Sensor 314 Second Sensor 316 Third Sensor 318 Power Supply 358 Fourth Sensor 360 Fifth sensor 362 Sixth sensor 370 Allowable value display unit 380 Name display unit 390 Control display unit 400 Setting screen 410 Usage frequency setting unit 420 Power consumption display unit 430 Power consumption total display unit 450 Control setting unit 460 Usage frequency display unit

Claims (9)

An image forming apparatus that takes one of a sleep mode and a normal operation mode that shift when an unused state continues for a predetermined time or more,
First and second detection means for respectively detecting an event that triggers a transition from the sleep mode to the normal operation mode;
First and second power supply means for supplying power to the first and second detection means, respectively;
In the sleep mode, timing for periodically controlling the first and second power supply units at a constant cycle so that periods of supplying power to the first and second detection units do not overlap each other. An image forming apparatus including a control unit.   The image forming apparatus according to claim 1, wherein lengths of power supply periods by the timing control unit to the first and second detection units are equal to each other.   The image forming apparatus according to claim 1, wherein lengths of power supply periods to the first and second detection units by the timing control unit are different from each other.   4. The image forming apparatus according to claim 1, wherein frequencies of power supply periods to the first and second detection units by the timing control unit are equal to each other within the period. 5.   4. The image forming apparatus according to claim 1, wherein frequencies of power supply to the first and second detection units by the timing control unit are different from each other within the period. 5. Storage means for storing order information indicating the order in which power is supplied to the first and second detection means within the cycle;
6. The image formation according to claim 1, wherein the timing control unit periodically supplies power to the first and second detection units in accordance with the order stored in the storage unit. apparatus. The storage means further stores power supply availability information indicating whether or not to supply power to the first and second detection means,
7. The timing control unit according to claim 6, wherein the timing control unit determines whether or not to supply power to the first and second detection units within the period according to the power supply availability information stored in the storage unit. The image forming apparatus described. The storage means further stores a period length per cycle when power is supplied to the first and second detection means,
The timing control means determines a period for supplying power per cycle to the first and second detection means according to the period length stored in the storage means. The image forming apparatus described.   The image forming apparatus according to claim 6, further comprising a setting unit used to set information stored in the storage unit.

Images