JP2018017897A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which can reduce power consumption efficiently.SOLUTION: A multi-function machine 11 includes an image-forming request receiving unit 56, a number-of-copies detection unit 57, and a power supply control unit 58. The image-forming request receiving unit 56 receives image data and an image-forming request. The number-of-copies detection unit 57 detects the number of images to be formed received by the image-forming request receiving unit 56. When the image-forming request receiving unit 56 receives the image-forming request in a second mode, the power supply control unit 58 controls power to be supplied from a power supply unit 25, in accordance with the number of images to be formed detected by the number-of-copies detection unit 57.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an image forming apparatus.

  In an image forming apparatus typified by a multifunction peripheral, light is irradiated on a photoconductor based on image data to form an electrostatic latent image on the photoconductor. Thereafter, charged toner is supplied onto the formed electrostatic latent image to form a toner image. Then, after the toner image is transferred to the paper, the toner image is fixed to the paper. The sheet on which the toner image is fixed is discharged out of the apparatus.

  An image forming apparatus disposed in an office is connected to a plurality of computers via a network. Some image forming apparatuses shift to a sleep mode that saves power during standby when a print request from a computer is not accepted for a predetermined time. When such an image forming apparatus accepts a request for image formation, it supplies power to the fixing device and shifts to a standby mode in which image formation can be performed immediately to perform image formation. Technologies relating to power saving during standby are disclosed in Japanese Unexamined Patent Application Publication No. 2008-145812 (Patent Document 1), Japanese Unexamined Patent Application Publication No. 2010-66372 (Patent Document 2), and Japanese Unexamined Patent Application Publication No. 2010-269696 (Patent Document 3). Has been.

  The image forming apparatus disclosed in Patent Document 1 forms an image by fixing a toner image on a recording sheet. An image forming apparatus disclosed in Patent Document 1 includes a fixing unit that fixes a toner image on a recording sheet, an operation unit that receives an operation input from a user, and a sleep mode for power saving or power saving. A fixing control means for starting heating of the fixing means in order to set the temperature of the fixing means to a target temperature at the time of return of the fixing means, and the fixing control means is controlled by the operating means during the heating of the fixing means. The heating of the fixing unit is stopped when an operation input for selecting a predetermined function that does not require heating of the fixing unit is received.

  An image forming apparatus disclosed in Patent Document 2 includes a solar cell panel for supplying power to the image forming apparatus, and a control unit that monitors an output value of the solar cell panel, and the control unit includes the solar cell panel. When a decrease in output is detected, the power saving operation mode is returned to the normal operation mode.

  An image processing apparatus disclosed in Patent Document 3 includes an engine unit that forms a visible image on a sheet-like recording medium, a controller unit that controls the entire apparatus including the engine unit, and a power source for the engine unit and the controller unit. A power supply unit for supplying the power. The controller unit includes: an energy saving control unit that controls power supply to each unit according to a state transition between an energy saving state and a normal state; a storage unit that stores a command and data for performing a startup process; and an energy saving state. Trajectory control means for controlling activation to a normal state. The trajectory control means determines whether the start is a cold start or a warm start based on the data stored in the storage means, and selects one of the start based on the determination to execute the start processing It is said.

JP 2008-145812 A JP 2010-66372 A JP 2010-269496 A

  An image forming apparatus that has received a request for image formation in the sleep mode supplies power to the fixing device or the like with so-called full power in order to immediately enable image formation. However, with such a configuration, when the image formation is completed after a few sheets, and the image formation request is not accepted for a while, the sleep mode is resumed. Such a situation leads to unnecessary power consumption, which is not preferable from the viewpoint of power saving. In addition, it is difficult to cope with such a problem with the techniques disclosed in Patent Documents 1 to 3 described above.

  An object of the present invention is to provide an image forming apparatus capable of efficiently reducing power consumption.

  The image forming apparatus according to the present invention has a first mode in which power consumption during standby is a predetermined amount of power, and a second mode in which the amount of power is less than the predetermined amount of power. The image forming apparatus includes an image formation request receiving unit, a number detection unit, a developing unit, a transfer unit, a fixing roller, a heater, a power supply unit, and a power supply control unit. The image formation request receiving unit receives an image formation request together with image data. The number detection unit detects the number of image formations received by the image formation request reception unit. The developing unit forms an electrostatic latent image from the image data received by the image formation request receiving unit, and forms a toner image by attaching toner to the electrostatic latent image. The transfer unit transfers the toner image formed by the developing unit to a sheet. The fixing roller fixes the toner image on the sheet on which the toner image is transferred by the transfer unit. The heater heats the fixing roller. The power supply unit supplies power to the heater. If the image formation request accepting unit accepts the image formation request in the second mode, the power supply control unit supplies the power supplied by the power supply unit according to the number of image formations detected by the number detection unit. Control.

  According to such an image forming apparatus, the power to be supplied is controlled according to the number of received image formations. Then, for example, when the number of image formations is relatively small, it is possible to heat the fixing roller without supplying excessive power so that image formation is possible. Therefore, according to such an image forming apparatus, it is possible to efficiently reduce power consumption.

1 is a diagram illustrating a multifunction peripheral when an image forming apparatus according to an embodiment of the present invention is applied to the multifunction peripheral. FIG. 2 is a block diagram illustrating a configuration of the multifunction machine illustrated in FIG. 1. FIG. 2 is a diagram illustrating a schematic configuration of an image forming unit. It is a block diagram which shows the structure of a control part. 6 is a flowchart illustrating a processing flow when a print request is issued from a computer using a multifunction peripheral. It is a figure which shows the relationship between time and the temperature of a fixing roller. The relationship between power consumption until return and return time is shown.

  Embodiments of the present invention will be described below. FIG. 1 is a diagram illustrating a multifunction peripheral when an image forming apparatus according to an embodiment of the present invention is applied to the multifunction peripheral. FIG. 2 is a block diagram illustrating a configuration of the multifunction peripheral illustrated in FIG.

  Referring to FIGS. 1 and 2, the multi-function device 11 has a plurality of functions such as a copying function, a printer function, and a facsimile function regarding image processing. The multifunction machine 11 includes a control unit 12, an operation unit 13, an image reading unit 14, an image forming unit 15, a paper feed cassette 16, a hard disk 17, a network interface unit 18 for connecting to a network 23, And a power supply unit 25. In FIG. 1, the control unit 12 is indicated by a one-dot chain line, and the image forming unit 15 is indicated by a two-dot chain line.

  The control unit 12 controls the entire multifunction machine 11. The control unit 12 includes a CPU and the like, and includes a main memory 19 that temporarily stores data. The operation unit 13 includes a touch panel type display screen 21 as a display unit that displays information transmitted from the multifunction machine 11 side and user input contents. The operation unit 13 accepts input from the user regarding image formation such as the number of copies to be printed and image forming conditions such as gradation. The image reading unit 14 includes an ADF (Auto Document Feeder) 22 as a document transport device that transports a document set at the set position to the read position. The image reading unit 14 reads an image of a document set on the ADF 22 or a mounting table (not shown). A plurality of paper feed cassettes 16 serving as a paper storage unit are provided, and a plurality of paper sheets can be stored therein. The image forming unit 15 forms an image on a sheet conveyed from the sheet feeding cassette 16 or the like based on the image data of the original read by the image reading unit 14 or the image data transmitted via the network 23. In other words, the image forming unit 15 forms and prints an image on a sheet stored in the sheet feeding cassette 16 or the like. The hard disk 17 stores data related to image formation such as transmitted image data and input image forming conditions. The power supply unit 25 supplies power to each member constituting the image forming unit 15, for example, a heater 44 and an operation unit 13 described later.

Next, the configuration of the image forming unit 15 described above will be described in more detail. FIG. 3 is a diagram illustrating a schematic configuration of the image forming unit 15. Referring to FIG. 3, the image forming unit 15 includes a developing unit 31 that forms a toner image on a sheet 46 using toner. A developing unit 31 indicated by a two-dot chain line in FIG. 3 includes a photosensitive member 32 that forms an electrostatic latent image on the surface thereof, a charging unit 33 that charges the surface of the photosensitive member 32, a developing sleeve, and a plurality of stirring rollers. A toner formed on the surface of the photoreceptor 32, including a developing unit 34 that supplies toner to the surface of the photoreceptor 32 on which the electrostatic latent image is formed to form a toner image, and a transfer charger and a separation charger. A transfer unit 35 that transfers the image onto the conveyed paper 46, a charge-removing roller, a cleaning blade, and the like. And a cleaning unit 36 for removing the. Photoreceptor 32 rotates in the direction of the arrow R ₁ in FIG. The developing unit 34 forms an electrostatic latent image from image data received by an image formation request receiving unit 56 described later, and forms a toner image by attaching toner to the electrostatic latent image. The transfer unit 35 transfers the toner image formed by the developing unit 34 to a sheet. The image forming unit 15 repeatedly charges, develops, transfers, and cleans the photoreceptor 32 to form a toner image on the conveyed paper 46. Note that toner consumed by development is supplied to the development unit 34 as needed by a toner container (not shown) detachably provided in the development unit 31.

  The image forming unit 15 includes a fixing device 41 that fixes the toner image formed on the paper 46 by the developing unit 34 to the paper 46. The fixing device 41 includes a hollow rotatable fixing roller 42 that heats the paper 46 when the toner is fixed to the paper 46, and a solid rotatable that pressurizes the paper 46 when the toner is fixed to the paper 46. It includes a fixing roller 43, a heater 44 that heats the fixing roller 42, and a thermistor 45 that detects the temperature of the fixing roller 42. The fixing roller 42 is also called a heat roller. The fixing roller 43 is also called a pressure roller. The fixing rollers 42 and 43 fix the toner image on the sheet on which the toner image is transferred by the transfer unit 35.

  The fixing roller 42 has a cylindrical shape and is mainly composed of a metal base tube. A heater 44 is disposed on the inner side of the fixing roller 42. The thermistor 45 is also arranged in contact with or non-contact with the fixing roller 42. The heater 44 is composed of a so-called halogen heater, and is turned on by the power supplied from the power supply unit 25 to heat the fixing roller 42.

  The fixing roller 43 is mainly composed of a rubber-like cylindrical member having elasticity. The fixing roller 42 and the fixing roller 43 are in contact with each other. Specifically, the fixing roller 42 and the fixing roller 43 are provided so that the surface of the fixing roller 42 and the surface of the fixing roller 43 are in contact with each other in the longitudinal direction. Since the fixing roller 42 and the fixing roller 43 are in contact with each other, the heat of the fixing roller 42 is transmitted to the fixing roller 43 to some extent. That is, the fixing roller 42 and the fixing roller 43 have almost the same temperature distribution in the longitudinal direction. The sheet 46 is conveyed to the contact area between the fixing roller 42 and the fixing roller 43, and the toner image formed on the sheet 46 is fixed to the sheet by heat and pressure.

Fixing roller 43 rotates in the direction of the arrow R ₂ in FIG. The fixing roller 42 rotates in the opposite direction to the fixing roller 43. The sheet 46 is conveyed from the upstream side to the downstream side by the rotation of the fixing roller 42 and the fixing roller 43. During this conveyance, the toner image formed on the paper 46 is fixed by the fixing roller 42 and the fixing roller 43. Direction is conveyed in the sheet 46 is roughly indicated by arrow D ₁ of the in Figure 3.

  The image forming unit 15 is provided with a transport belt 37 provided between the developing unit 31 and the fixing device 41, and a plurality of paper feed rollers 38a, 38b, 38c, 38d, and 38e. For example, the paper 46 set on the manual feed tray 27 is transported through the paper transport paths 39 a, 39 b, 39 c, and 39 d by the paper feed rollers 38 a to 38 e and discharged to the discharge tray 26. Further, the paper 46 set in the paper feed cassette 16 is transported through the paper transport paths 39b to 39d by the paper feed rollers 38b to 38e, and is discharged to the discharge tray 26.

  Here, the multifunction machine 11 has a first mode in which power consumption during standby is a predetermined amount of power, and a second mode in which the amount of power is less than the predetermined amount of power. The first mode is called a so-called standby mode, and consumes a relatively large amount of power during standby. Under this mode, if image formation is required, image formation can be performed immediately. Specifically, the first mode is a state in which electric power is supplied to the fixing rollers 42 and 43 required for fixing the toner on the sheet as needed, and the toner is constantly maintained at a temperature at which the toner can be fixed. On the other hand, the second mode is a so-called sleep mode and consumes relatively little power during standby. In this mode, since the fixing rollers 42 and 43 are maintained at a temperature lower than the temperature at which the toner can be fixed, even if image formation is required, image formation cannot be performed immediately. . This mode is a standby mode in which an image can be formed after a predetermined time has elapsed after receiving a request for image formation. The predetermined time is a time required to heat the fixing rollers 42 and 43 to a temperature at which the fixing rollers 42 and 43 can be fixed, or to charge the toner to a developing level by stirring.

  Next, the configuration of the computer 51 will be described. A display 52, a keyboard 53, and a mouse 54 are connected to the computer 51. Information and data from the computer 51 are displayed on the display 52. In addition, the user inputs data to the computer 51 using the keyboard 53 and the mouse 54. A user who requests printing using the multifunction device 11 uses the keyboard 53 and mouse 54 connected to the computer 51 to transmit a print command to the multifunction device 11 together with image data requesting printing via the network 23. To do. In accordance with the received print command, the multifunction machine 11 forms an image on a sheet based on the received image data, prints it, and outputs it.

  Next, the configuration of the control unit 12 will be described. FIG. 4 is a block diagram illustrating a configuration of the control unit 12. Referring to FIG. 4, the control unit 12 includes an image formation request receiving unit 56, a number detection unit 57, and a power supply control unit 58. The image formation request receiving unit 56 receives an image formation request together with image data. Specifically, when accepting an image formation request from the computer 51, the image formation request acceptance unit 56 accepts print requests and various settings for printing as well as receiving image data via the network 23. The number detection unit 57 detects the number of image formations received by the image formation request reception unit 56. That is, the number of printed sheets is detected from various print settings. If the image formation request accepting unit 56 accepts an image formation request in the second mode, the power supply control unit 58 supplies the power supply unit 25 according to the number of image formations detected by the number detection unit 57. Control the power generated. These configurations will be described in detail later.

  Next, a case where a print request is made from the computer 51 using the multifunction machine 11 will be described. FIG. 5 is a flowchart showing the flow of processing when a request for printing is made from the computer 51 using the multifunction machine 11.

  Referring to FIG. 5, the user uses the display 52 from the computer 51 to operate the keyboard 53 or the mouse 54 to make a request for image formation to the multifunction machine 11. Then, the image formation request accepting unit 56 accepts an image formation request from the computer 51, that is, a print request, via the network 23 (step S11 in FIG. 5, hereinafter, “step” is omitted). At this time, the image formation request receiving unit 56 receives image data for image formation and also receives the number of image formations.

  Thereafter, the number detection unit 57 detects the number of images formed (S12). In this case, for example, data of the number of printed sheets is extracted from various settings of the transmitted printing and detected.

  Next, when the multifunction machine 11 is in the second mode, that is, the sleep mode, power is supplied. Here, when supplying power, if the power supply control unit 58 receives a request for image formation from the image formation request reception unit 56 in the second mode, it corresponds to the number of image formations detected by the number detection unit 57. Then, the power supplied by the power supply unit 25 is controlled (S13).

Here, control of supplied power will be described. FIG. 6 is a diagram illustrating the relationship between time and the temperature of the fixing rollers 42 and 43. In FIG. 6, the vertical axis indicates the temperature of the fixing rollers 42 and 43, and the horizontal axis indicates time. In the vertical axis, the fixable temperature S ₁ in the fixing roller 42 and 43 is shown by a chain line. Line 61a is a diagram showing the power supplied _{P 1.} Line 61b is a diagram showing the power supplied _{P 2.} Line 61c is a diagram showing the power supplied _{P 3.} The electric power P ₁ is the largest, and then the electric power P ₂ and the electric power P ₃ are decreased in this order.

6, when the power is supplied by power P ₁ indicated by line 61a, since the largest power P _1, the time T ₁ of the to reach the fixable temperature S ₁ becomes very short. And the power is supplied next highest power P ₂ indicated by line 61b, the time T ₂ of the to reach the fixable temperature S ₁ is longer than the time T _1. And the power is supplied by the smallest power P ₃ indicated by line 61c, the time T ₃ to reach the fixable temperature S ₁ is longer than the time T _2. That is, longer than the time _{T 1.} 6, when the large power P ₁ supplied, the time required for recovery is shorter. Conventionally, in order to aim to return a minimum on the basis of this idea, at full power the power P _1, i.e., has been decided to provide at best.

  Here, Table 1 shows the relationship between the return time, that is, the time required for the fixing rollers 42 and 43 to be heated again to the fixable temperature and image formation can be performed, and the output power of the heater 44.

  Table 1 shows data obtained by assigning the recovery time, that is, the time from the sleep mode to the standby mode in four steps from 30 seconds to 60 seconds in units of 10 seconds. The heater output control according to the length of the return time and the lighting control are shown. And the power consumption in each case and the power consumption ratio when 30 seconds are set to 100 are also shown.

  FIG. 7 shows the relationship between the power consumption until return and the return time. In FIG. 7, the vertical axis indicates power consumption until return, and the horizontal axis indicates return time. A line 62 in FIG. 7 shows the relationship between the power consumption and the return time.

  Referring to Table 1 and FIG. 7, the power consumption required for the return increases relatively if the return time is relatively short. Specifically, in Table 1, the output of the heater 44 is controlled to 1000 W with the aim of returning in 30 seconds. Further, regarding the lighting control of the heater 44, the continuous heater 44 is turned on. On the other hand, if the return in 40 seconds is aimed, the output of the heater 44 may be controlled to 700W. In addition, the lighting control of the heater 44 may be turned on for 7 seconds and turned off for 3 seconds. That is, the blinking pattern of the heater 44 is set in this way. The power consumption ratio at this time is 93, where 100 is 30 seconds. Furthermore, if it is intended to return in 50 seconds, the output of the heater 44 may be controlled to 500W. Further, the lighting control of the heater 44 may be turned on for 5 seconds and turned off for 5 seconds. That is, the blinking pattern of the heater 44 is set in this way. The power consumption ratio at this time is 85, where 100 is 30 seconds. Further, if it is intended to return in 60 seconds, the output of the heater 44 may be controlled to 400W. In addition, the lighting control of the heater 44 may be turned on for 4 seconds and turned off for 6 seconds. That is, the blinking pattern of the heater 44 is set in this way. The power consumption ratio at this time is 80, where 100 is 30 seconds. That is, power consumption of 4/5 is sufficient.

  Also, referring to FIG. 7, even when the recovery time is relatively long, the power consumption is relatively increased. That is, in Table 1, the power consumption is the smallest for any value after the return time of 60 seconds, and the power consumption gradually increases with that value as the lower limit.

  Here, the return time is not aimed at the shortest, but if it takes a certain amount of time, the power consumption until the return can be reduced. In this way, the power to be supplied is controlled according to the number of sheets from the correlation between the return time and the power consumption. That is, if the power supply control unit 58 receives a request for image formation from the image formation request reception unit 56 in the second mode, the power supply unit 25 corresponds to the number of image formations detected by the number detection unit 57. To control the power supplied. Then, the power supply control unit 58 performs control so that the power supplied by the power supply unit 25 decreases as the number of image formations detected by the number detection unit 57 decreases. Specifically, instead of aiming to return from the sleep mode by suddenly turning on the power in response to all image formation requests suddenly, the power is reduced so that the power consumption is reduced according to the number of images required for image formation. Adjusting the time to put in, reduce the total power consumption. In this case, for example, if the number of image formation is one or two or less, the control is performed to supply power with the above-described return time of 60 seconds. If the number of image formations is 15 or more, control is performed to supply power with the above-described recovery time of 50 seconds. For example, when the number of image formations is 50 or more, power may be supplied at full power. In this case, since the printing is continuously performed, there is less possibility that the power required at the time of return is wasted.

  In this way, the fixing rollers 42 and 43 are heated by the heater 44. If fixing rollers 42 and 43 have reached the fixable temperature (YES in S14), image formation is executed (S15). In this way, the process ends.

  According to such a multifunction machine 11, the power to be supplied is controlled according to the number of received image formations. Then, for example, when the number of image formations is relatively small, it is possible to heat the fixing rollers 42 and 43 without supplying excessive power so that image formation is possible. Therefore, according to such a multi-function device 11, it is possible to efficiently reduce power consumption.

  In this case, since the power supplied by adjusting the blinking pattern of the heater 44 is controlled, the power consumption can be reduced more efficiently.

  In the above embodiment, the blinking pattern of the heater 44 is not adjusted. However, the present invention is not limited to this, and the power supplied may be controlled by reducing the output of the heater 44. .

  In the above embodiment, the power supply control unit 58 determines the temperature of the fixing rollers 42 and 43 in the first mode if the number of image formations detected by the number detection unit 57 is equal to or greater than a predetermined number. Until it becomes, you may make it control to supply electric power continuously by the electric power supply part 25. In this way, image formation can be performed while reducing power consumption more efficiently.

  In the above-described embodiment, when returning from the sleep mode, it is possible to select whether to give priority to power consumption or return time. By doing so, it is possible to perform image formation more in line with user needs.

  It should be understood that the embodiments disclosed herein are illustrative in all respects and are not restrictive in any aspect. The scope of the present invention is defined by the scope of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the scope of the claims.

  The image forming apparatus according to the present invention is particularly effectively used when efficient power consumption reduction is required.

  DESCRIPTION OF SYMBOLS 11 MFP, 12 Control part, 13 Operation part, 14 Image reading part, 15 Image formation part, 16 Paper feed cassette, 17 Hard disk, 18 Network interface part, 19 Main memory, 21 Display screen, 22 ADF, 23 Network, 25 Power supply unit, 26 Discharge tray, 27 Manual feed tray, 31 Developing unit, 32 Photoconductor, 33 Charging unit, 34 Developing unit, 35 Transfer unit, 36 Cleaning unit, 37 Conveying belt, 38a, 38b, 38c, 38d, 38e Paper feed roller, 39a, 39b, 39c, 39d Paper transport path, 41 Fixing device, 42, 43 Fixing roller, 44 Heater, 45 Thermistor, 46 Paper, 51, Computer, 52 Display, 53 Keyboard, 54 Mouse, 56 Image formation Request acceptance Parts, 57 number detecting unit, 58 power supply control unit, 61a, 61b, 61c, 62 lines.

Claims (5)

An image forming apparatus having a first mode in which power consumption during standby is a predetermined amount of power and a second mode in which the amount of power consumption is less than the predetermined amount of power,
An image formation request receiving unit that receives an image formation request together with image data;
A number detection unit that detects the number of image formations received by the image formation request reception unit;
A developing unit that forms an electrostatic latent image from the image data received by the image formation request receiving unit, and forms a toner image by attaching toner to the electrostatic latent image;
A transfer unit that transfers the toner image formed by the developing unit to a sheet;
A fixing roller for fixing the toner image on a sheet onto which the toner image has been transferred by the transfer unit;
A heater for heating the fixing roller;
A power supply unit for supplying power to the heater;
If the image formation request acceptance unit accepts the image formation request in the second mode, the power supplied by the power supply unit is set according to the number of image formations detected by the number detection unit. An image forming apparatus comprising: a power supply control unit that controls the image forming apparatus. The image forming apparatus according to claim 1, wherein the power supply control unit controls to reduce an output of the power supplied from the power supply unit. The heater includes a halogen heater that heats the fixing roller by lighting,
The image forming apparatus according to claim 1, wherein the power supply control unit controls the power supplied by the power supply unit by adjusting a blinking pattern of the halogen heater. 4. The power supply control unit according to claim 1, wherein the power supply control unit controls the power supplied by the power supply unit to be smaller as the number of image formations detected by the number detection unit decreases. The image forming apparatus described in 1. If the number of image formations detected by the number detection unit is equal to or greater than a predetermined number, the power supply control unit continuously uses the power supply unit until the temperature of the fixing roller in the first mode is reached. The image forming apparatus according to claim 1, wherein the power is controlled so as to supply the power.

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