JP2012037579A - Image formation device and its control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress electric power consumption in heating of a fixing device, without increasing stand-by time for the fixing device temperature to reach a predetermined temperature or complicating the structure, such as an additional mechanism for switching the electric power to heat the fixing device.SOLUTION: If a processing using a fixing device is supposed to be executed when a sleep mode is released, a preheating time from the start of preheating of the fixing device by a heating part until the fixing device temperature reaches an image formation temperature Tis calculated, based on the fixing device temperature detected by a temperature sensor, and the heating part is started to preheat the fixing device so as to complete the preheating at substantially the same time as a processing execution instruction by a user. (Refer to (C) and (D)).

Description

  The present invention relates to an image forming apparatus and a control program therefor.

  In Patent Document 1, in a complex system including an operation panel, a button is provided for each function of a copy, a document box, a fax, a printer, and a scanner so that the user cannot recover from the energy saving state unless one of the buttons is selected and pressed. Furthermore, there is disclosed a technology for suppressing power consumption when returning from an energy saving state by performing power recovery only for a portion necessary for the function.

  Further, in Patent Document 2, when returning from the sleep mode, only the necessary mechanism is initialized according to the content of the process to be started, and when the fixing mechanism is used, the temperature of the heated member is detected, A technique for switching the power supplied to the induction heating means or the lamp heating means in accordance with the temperature of the member to be heated is disclosed.

JP 2004-222234 A Japanese Patent No. 3400402

  The present invention eliminates an increase in waiting time until the temperature of the fixing device reaches a preset temperature and a complicated configuration such as providing a mechanism for switching electric power for heating the fixing device. An object of the present invention is to obtain an image forming apparatus and a control program for the image forming apparatus that can reduce power consumption during heating.

  In order to achieve the above object, the image forming apparatus according to the first aspect of the present invention includes a heating unit that heats the fixing unit, a temperature detection unit that detects the temperature of the fixing unit, and a process that uses the fixing unit. The heating means while the estimation means for estimating whether or not the process is performed and the process using the fixing device is not being executed and the process using the fixing device is not estimated to be executed by the estimation means. The heating of the fixing device by the means is stopped, and the temperature of the fixing device detected by the temperature detecting means when the processing using the fixing device is estimated to be executed by the estimating means, or The time from the start of heating of the fixing device by the heating means until the temperature of the fixing device reaches a preset temperature, which is obtained from the elapsed time since the heating of the fixing device by the heating means is stopped. At a timing corresponding to time, and is configured to include a control means for performing control to start heating of the fixing device according to the heating means.

  According to a second aspect of the present invention, in the first aspect of the invention, the control unit stops the temperature of the fixing unit detected by the temperature detecting unit or the heating of the fixing unit by the heating unit. The required time is estimated on the basis of the elapsed time from the beginning, and heating of the fixing device by the heating means is started at a timing before the required time estimated from the estimated use start time of the fixing device.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, an image reading unit that reads an image of a set original, a set of the original on the image reading unit, and a document on the image reading unit. Detecting means for detecting at least one of operations for reading an image, and the estimating means sets a document on the image reading unit and reads an image of the document on the image reading unit. When at least one of the operations is detected by the detection means, it is assumed that the process using the fixing device is executed, and the control means uses the detection means as the scheduled start time of use of the fixing device. The time after a preset time after at least one of the setting of the document on the image reading unit and the operation for reading the image of the document at the image reading unit is detected. There.

  According to a fourth aspect of the present invention, in the third aspect of the invention, the apparatus further includes a specifying unit for a user to specify a process to be executed, and the control unit sets the document on the image reading unit and the The heating unit is configured such that at least one of operations for reading an image of a document in the image reading unit is detected by the detection unit, and it is estimated that a process using the fixing device is executed by the estimation unit. After the heating of the fixing device is started, when the processing that does not use the fixing device is specified through the specifying means as the processing to be executed, the heating of the fixing device by the heating means is stopped.

  According to a fifth aspect of the present invention, there is provided a control program for an image forming apparatus, comprising: a computer built in an image forming apparatus, comprising: a heating unit that heats a fixing unit; and a temperature detection unit that detects a temperature of the fixing unit. , An estimation means for estimating whether or not the process using the fixing device is executed, and a process using the fixing device is not executed and a process using the fixing device is executed by the estimation means. When it is estimated that the heating unit stops heating the fixing unit and the estimation unit estimates that the process using the fixing unit will be executed, the temperature detection unit detects the temperature. Further, the temperature of the fixing device or the elapsed time after the heating of the fixing device by the heating means is obtained, and then the temperature of the fixing device is started after the heating means starts heating of the fixing device. At a timing corresponding to the time required until the temperature of the vessel reaches a predetermined temperature, to function as control means for performing control to start heating of the fixing device according to the heating means.

  The inventions according to claims 1 and 5 increase the waiting time until the temperature of the fixing device reaches a preset temperature, and complicate the configuration such as providing a mechanism for switching electric power for heating the fixing device. There is an effect that it is possible to suppress power consumption in heating the fixing device without incurring.

  The invention according to claim 2 has the effect that the heating start timing of the fixing device can be optimized.

  According to the third aspect of the present invention, when an operation for reading an image of a document is performed by the image reading unit before a process to be executed is specified, heating of the fixing device can be started early. It has the effect that it becomes possible.

  In the invention described in claim 4, although the heating of the fixing device is started by the operation for reading the image of the original in the image reading unit, the processing to be executed is processing that does not use the fixing device. In this case, useless power consumption can be suppressed.

1 is a block diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment. It is a block diagram which shows the detailed structure of a controller. 5 is a chart showing various control signals, various power supplies, and on / off of each functional module in various operating states. It is an image figure which shows an example of an initial menu screen. It is a flowchart which shows the content of the process at the time of the image formation part ON performed by MCU of an image formation part. It is a diagram showing an example of a temperature change of the fixing device.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an image forming apparatus 10 according to this embodiment. The image forming apparatus 10 has a function as a copying machine, a function as a printer, and a function as a scanner. The image forming apparatus 10 includes a controller 12 that controls the operation of the entire image forming apparatus 10, a display unit 14 A including an LCD, and the like. An operation panel 14 that includes a numeric keypad, a touch panel, and the like and is provided with an operation receiving unit 14B that receives an operation by a user, and an image reading unit that optically reads a set document (paper document) to be read and outputs read image data Each of the functional modules includes a unit 16 and an image forming unit 18 that forms an image represented by the input image data on a recording sheet.

The controller 12 is connected to a first power supply unit 20, and the first power supply unit 20 is connected to a commercial power supply via a main power switch 26. The first power supply unit 20 rectifies the AC power supplied from the commercial power supply while the main power switch 26 is turned on to generate a first DC low voltage V _L −1 (for example, a DC voltage of 5 V). , And supplied to the controller 12 as the first DC low voltage power.

The controller 12, the image reading unit 16 and the image forming unit 18 are connected to a second power supply unit 22, and the second power supply unit 22 is connected to a commercial power supply via a power supply switch 24 and a main power switch 26. ing. The second power supply unit 22 rectifies the AC power supplied from the commercial power source while the power supply switch 24 and the main power switch 26 are turned on, and generates a second DC low voltage V _L -2 (for example, a DC voltage of 5 V). Voltage) and a DC high voltage V _H (for example, a DC voltage of 24 V), respectively, and the second DC low voltage V _L -2 is supplied to the controller 12, the image reading unit 16 and the image forming unit 18. In addition to being supplied as electric power, the DC high voltage V _H is supplied as DC high voltage power to the controller 12 and the image forming unit 18.

  The power supply switch 24 is composed of, for example, a relay or a semiconductor element and can be switched on / off by an on / off signal supplied from the outside. The power supply switch 24 is connected to the controller 12 and is turned on / off by a sleep signal SLEEP_ON supplied from the controller 12. The state of is switched.

  As shown in FIG. 2, the controller 12 includes a CPU 54, to which a memory bus 56, a first PCI (Peripheral Component Interconnect) bus 58, and a second PCI bus 60 are connected. A DRAM 62 and a flash memory 64 are respectively connected to the memory bus 56, and a power saving control program for the CPU 54 to perform power saving control described later is stored in the flash memory 64 in advance. The controller 12 functions as an example of an estimation unit according to the present invention by the CPU 54 executing the above power saving control program.

  Further, a UI (User Interface) control circuit 66 and a video I / F circuit 68 are connected to the first PCI bus 58. An operation panel 14 is connected to the UI control circuit 66, and the UI control circuit 66 supplies power to the operation panel 14 and transmits / receives information to / from the operation panel 14 (for example, a screen to be displayed on the display unit 14A). Information and transmission / reception of signals according to operations performed by the user via the operation reception unit 14B. For example, the operation receiving unit 14B of the operation panel 14 is provided with a power saving cancel button (not shown) for the user to instruct the power saving state image forming apparatus 10 to cancel the power saving state. When the power saving cancel button is operated by the user while power is being supplied to the PC, a signal corresponding to the operation is directly input to the CPU 54 from the operation panel 14 without passing through the UI control circuit 66, thereby enabling the use. The CPU 54 (controller 12) detects that the person has operated the power saving cancel button.

  The video I / F circuit 68 is connected to the image reading unit 16 and the image forming unit 18. The video I / F circuit 68 transmits and receives information to and from the image reading unit 16 and the image forming unit 18. Control. For example, the controller 12 outputs an image reading unit ON signal IIT_ON (see FIG. 1) for turning on / off the operation of the image reading unit 16 to the image reading unit 16 via the video I / F circuit 68 to operate the image forming unit 18. An image forming unit on signal IOT_ON for turning on / off the image forming unit and a preheating preparation signal P_HEAT (see FIG. 1) for instructing preheating preparation of the fixing device are output to the image forming unit 18 via the video I / F circuit 68.

  The image reading unit 16 is supplied with the second DC low-voltage power from the second power supply unit 22 and the image reading unit ON signal IIT_ON input from the controller 12 is in a signal state corresponding to “ON”. The image forming unit 18 is supplied with the second DC low voltage power and the DC high voltage power from the second power supply unit 22 and the image forming unit ON signal IOT_ON input from the controller 12 is “ It operates while it is in the signal state corresponding to “ON”.

  A host I / F circuit 70 and a power supply control circuit 72 are connected to the second PCI bus 60, respectively. A host PC 76 can be connected to the image forming apparatus 10 via a USB (Universal Serial Bus) interface or a LAN (Local Area Network) interface, and the host I / F circuit 70 is connected via a USB interface or a LAN interface. It manages communication with the connected host PC 76. An HDD (Hard Disk Drive) 74 is connected to the host I / F circuit 70 via an IDE (Integrated Drive Electronics) interface, and the host I / F circuit 70 is also responsible for sending and receiving information to and from the HDD 74. The HDD 74 may be connected via an interface such as SATA.

  The image forming apparatus 10 is provided with a power switch 28 (see also FIG. 1) that is turned on and off by a user operation. One end of the power switch 28 is grounded, the other end is connected to the power supply line via the resistor 30, and is connected to the power switch monitoring circuit 72A built in the power control circuit 72 via a signal line. The on / off state of the switch 28 is monitored by the power switch monitoring circuit 72A of the power control circuit 72, and the change in the on / off state of the power switch 28 is detected by the CPU 54 (controller 12) via the power switch monitoring circuit 72A.

  In addition, the image reading unit 16 includes an automatic document feeding unit (not shown) and, as shown in FIG. 1, a document set detection switch that switches on and off depending on whether or not a document is set on the automatic document feeding unit. 32 is provided. The document set detection switch 32 has one end grounded and the other end connected to the power supply line via the resistor 34 and to the controller 12 via the signal line. The document set detection switch 32 is in an on / off state. The document detection signal PAPER is input to the controller 12. The document set detection is generally performed by detecting reflected light with a reflection type photosensor, and the document set detection switch 32 shown in FIG. 1 schematically shows this configuration.

  The image reading unit 16 is also provided with a cover open / close detection switch 36 that is turned on and off in accordance with opening / closing of a cover that closes the platen glass on which the document is placed. One end of the cover open / close detection switch 36 is grounded, and the other end is connected to the power supply line via a resistor 38 and to the controller 12 via a signal line. The on / off state of the cover open / close detection switch 36 is as follows. The cover opening / closing detection signal COVER is input to the controller 12.

  Accordingly, when the on / off state of the document set detection switch 32 or the cover open / close detection switch 36 changes, the change of the on / off state is caused by the CPU 54 (controller 12) regardless of whether the image reading unit 16 is operating. Detected. The document set detection switch 32 and the cover open / close detection switch 36 are an example of a detection unit.

  The image forming unit 18 is provided with an MCU 40, a fixing unit 42, and a post-processing device 44. The MCU 40 is composed of a microcomputer or the like, and incorporates a non-volatile storage unit 40B composed of a CPU 40A, a memory (not shown), a flash memory, and the like. An image forming unit control program is stored in advance in the storage unit 40B, and this image forming unit control program includes a program for executing processing when the image forming unit is turned on, which will be described later. It is an example of the control program of the image forming apparatus according to the present invention together with the power saving control program. The MCU 40 performs an image forming unit control process for controlling the operation of each unit of the image forming unit 18 by the CPU 40A executing the image forming unit control program while the image forming unit 18 is operating. The MCU 40 functions as an example of a control unit according to the present invention by the CPU 40A executing the image forming unit control program.

The fixing unit 42 includes a temperature sensor 46 that detects the temperature of a fixing device (not shown), a heating unit 48 that includes a heater and the like, and that heats the fixing device. There is provided a control unit 50 that controls heating of the fixing device by the heating unit 48 so that the temperature matches a preset image forming temperature T _F. The heating unit 48 is an example of a heating unit described in claim 1 and the like, and the temperature sensor 46 is an example of a temperature detection unit described in claim 1 and the like. A power supply line is connected to the fixing unit 42, and AC power from a commercial power source is supplied. Further, a fixing unit ON signal FSR_ON for turning on / off the operation of the fixing unit 42 is input from the MCU 40 to the fixing unit 42, and the fixing unit 42 is a signal in which the fixing unit ON signal FSR_ON input from the MCU 40 corresponds to “ON”. Operates while in a state.

  Further, a power supply line is also connected to the post-processing device 44, and AC power or DC high-voltage power from a commercial power source is supplied. Further, the post-processing device 44 receives a post-processing device ON signal FIN_ON from the MCU 40 for turning on / off the operation of the post-processing device 44, and the post-processing device 44 receives a post-processing device ON signal FIN_ON input from the MCU 40 as “ON”. It operates while the signal state corresponding to "." The post-processing performed by the post-processing device 44 includes, for example, decoloring processing that corrects paper warping (curl), folding processing that folds the paper at a preset position on the paper, and preset position on the paper. Punch processing that punches holes, staple processing that aligns the edges of multiple sheets and staples them as a single sheet bundle, offset processing that discharges paper (bundle) to different positions on the same discharge section, Examples include at least one of stack processing for stacking sheets (bundles), booklet processing for aligning the ends of a plurality of sheets, and the like.

Next, the operation of this embodiment will be described. In the image forming apparatus 10 according to the present embodiment, when the main power switch 26 is in the OFF state, the first power supply unit 20 and the second power supply unit are denoted as “main power SW off” in FIG. Since the operation of 22 is stopped, the generation of the first DC low voltage V _L −1, the second DC low voltage V _L −2 and the DC high voltage V _H is stopped. The functional modules of the panel 14, the image reading unit 16, and the image forming unit 18 (the MCU 40, the fixing unit 42, and the post-processing device 44) are stopped.

Here, when the main power switch 26 is switched from the OFF state to the ON state by the user, the first DC power supply 20 by the first power supply unit 20 as shown in FIG. Generation of the voltage V _L −1 is started, and the first DC low-voltage power is supplied from the first power supply unit 20 to the controller 12. As a result, the controller 12 starts to operate, and the CPU 54 first acquires the on / off state of the power switch 28 from the power switch monitoring circuit 72A of the power control circuit 72. If the power switch 28 is in the off state, the controller 12 itself is removed. Transition to power saving mode.

  That is, the CPU 54 stores the program and data stored in the flash memory 64 in the DRAM 62 (which reduces the processing time when returning from the power saving state), and then sets the DRAM 62 to the self-refresh mode. , Power supply to each device (for example, UI control circuit 66, video I / F circuit 68, host I / F circuit 70, HDD 74, etc.) other than the power control circuit 72 including the CPU 54, the DRAM 62, and the power switch monitoring circuit 72A. By turning it off, the operation of each device is stopped.

  When the user switches the power switch 28 from the off state to the on state and detects a change in the on / off state of the power switch 28 through the power switch monitoring circuit 72A of the power control circuit 72, the CPU 54 detects each device of the controller 12. Is turned on, the DRAM 62 is released from the self-refresh mode, and the program stored in the DRAM 62 is executed. As this program is executed, the CPU 54, as shown as “standby” in FIG. 3, sleep signal SLEEP_ON supplied to the power supply switch 24, image reading unit on signal IIT_ON output to the image reading unit 16, The image forming unit ON signal IOT_ON to be output to the image forming unit 18 is switched to a signal state corresponding to ON, and the operation panel 14 is also operated. As shown in FIG. 4, for example, each of copy, scan, and print An initial menu screen in which the functions are specified as options is displayed on the display unit 14A of the operation panel 14.

Accordingly, when the power supply switch 24 is turned on, generation of the second DC low voltage V _L -2 and the DC high voltage V _H by the second power supply unit 22 is started. The second DC low voltage power and the DC high voltage power are supplied to the image forming unit 18 and the second DC low voltage power is supplied from the second power supply unit 22 to the image reading unit 16. Further, the image reading unit 16 and the image forming unit 18 (the MCU 40 thereof) start operation, and the MCU 40 of the image forming unit 18 performs the fixing unit ON signal FSR_ON output to the fixing unit 42 and the post-processing output to the post-processing device 44. The device ON signal FIN_ON is switched to a signal state corresponding to ON.

  As a result, the fixing unit 42 and the post-processing device 44 start operation (the fixing unit 42 starts preheating of the fixing device by the heating unit 48), and the image forming apparatus 10 has copy, scan, and print functions. Transition to a standby state in which processing corresponding to any of these can be executed is made. Then, when one of the functions clearly indicated as options on the initial menu screen shown in FIG. 4 is selected by the operation of the operation receiving unit 14B of the operation panel 14 by the user, this corresponds to the selected function. When a designation screen for designating the processing content of the processing to be performed is displayed on the display unit 14A, and the processing content of the processing to be executed is designated through the displayed designation screen, the execution of the processing is instructed by the user. The processing instructed to be executed is executed by at least one of the image reading unit 16 and the image forming unit 18.

  Further, the controller 12 is provided with a timer, and the CPU 54 counts the elapsed time since the last processing in the image forming apparatus 10 by this timer. The timer value of this timer is reset every time a new process is started in the image forming apparatus 10, but the timer value is set to a preset low power mode transition time or sleep mode transition time (however, the low power mode transition is performed). When a value corresponding to time <sleep mode transition time) is reached, the CPU 54 controls one or more of the control signals as indicated by “low power mode” or “sleep mode” in FIG. Each signal is switched to a signal state corresponding to OFF.

  Thereby, first, in the “low power mode”, the operation of the operation panel 14 and the image reading unit 16 is stopped. In the “sleep mode”, the operations of the image forming unit 18 (the MCU 40, the fixing unit 42, and the post-processing device 44) and the second power supply unit 22 are further stopped. In the sleep mode, the operation state of the controller 12 is different from the state indicated as “Power OFF” in FIG. 3, and the portion of the host I / F circuit 70 that controls communication with the host PC 76 operates. It will be in a continuing state. In addition, as described above, the transition to the power saving state such as the low power mode and the sleep mode is not limited to the case where the elapsed time from the last processing has reached the preset transition time. For example, even when an operation that indicates an instruction to enter a power saving state is performed by the user, such as “the power saving release button has been pressed for a long time”, the time elapsed since the last processing was performed Regardless, the power saving state may be entered.

  By the way, when the image forming apparatus 10 in the sleep mode, which is one of the power saving states, desires to execute processing corresponding to any of the functions of copy, scan, and print, A power saving cancel button (not shown) provided in the reception unit 14B is pressed. As a result, the power saving state of the controller 12 is released, and the CPU 54 causes the display unit 14A of the operation panel 14 to display the above-described initial menu screen. Subsequently, the user selects an option corresponding to a process desired to be executed from among a plurality of options specified on the initial menu screen. If the option selected by the user is “copy”, the CPU 54 causes the image forming apparatus 10 to transition to the standby mode, causes the display unit 14A to display a designation screen corresponding to “copy”, and is selected by the user. If the option is “scan”, the image forming apparatus 10 is shifted to the reading unit on mode (see FIG. 3), and a designation screen corresponding to “scan” is displayed on the display unit 14A. If it is “print”, the image forming apparatus 10 is shifted to the forming unit on mode (see FIG. 3), and a designation screen corresponding to “print” is displayed on the display unit 14A.

  After that, if it is “copy” or “scan”, an operation for setting a document on the image reading unit 16 (an operation for setting a document on the automatic document feeder, or opening a platen glass cover and placing a document on the platen glass) To close the cover (this operation is an example of `` operation for reading the image of the original document with the image reading unit '') and operation to specify the processing content of `` copy '' or `` scan '' After being performed by the user, an operation for instructing execution of the process is performed by the user. In the case of “print”, the image forming apparatus 10 uses a recording medium in which data of a document to be printed is recorded (for example, a flash memory (so-called USB memory) added with a circuit that communicates with the outside via a USB interface). After the user has performed an operation for connecting to the printer or an operation for designating the processing content of “print”, an operation for instructing the execution of the processing is performed by the user.

  However, the user operation order described above is a general order, for example, before a user who desires to execute the “copy” or “scan” process performs an operation of pressing the power saving cancel button. Before an operation for setting a document on the image reading unit 16 or a user who desires to execute a “print” process performs an operation for pressing a power saving release button, the recording medium is inserted into the image forming apparatus 10. There is a possibility that an operation to connect to will be performed. When the operations are performed in this order, an operation for setting a document or an operation for connecting a recording medium to the image forming apparatus 10 is performed first, so that processing is performed after an option on the initial menu screen is selected. Since the time until the operation for instructing execution is shortened, the user waits for a relatively long time from when the operation for instructing execution of the process is performed until the execution of the process is actually started. There is a possibility.

For example, in FIG. 6A, a user who desires to execute a “copy” process (1) set a document on the image reading unit 16, (2) press the power saving cancel button, and (3) “copy”. This is the case where the operation is performed in the order of selection, (4) "copy" processing content specification, (5) "copy" processing execution instruction, but "(3)" copy "selection" operation As a trigger, the operation of the image forming unit 18 is started, and preheating of the fixing unit of the fixing unit 42 is started. At the stage where the user performs an operation of “(5)“ Copy ”process execution instruction”, the fixing unit Is not completed (the temperature of the fixing device has not reached the image formation temperature T _F ), and thus a waiting time for the user is generated.

Further, for the purpose of eliminating the waiting time of the user, the operation of the image forming unit 18 is started by using “(1) document set on the image reading unit 16” as a trigger, and preheating of the fixing unit of the fixing unit 42 is started. It is possible to make it. However, the temperature of the fixing device at the time when the preheating of the fixing device is started is the time during which the image forming apparatus 10 is in the sleep mode before the preheating of the fixing device is started (the image forming unit 18 (fixing unit 42)). Therefore, when the preheating of the fixing unit of the fixing unit 42 is started by using “(1) Document setting on the image reading unit 16” as a trigger, the fixing unit 42 In order to maintain the temperature at the temperature _TF during image formation, useless power consumption may occur.

For example, in the example shown in FIG. 6B, the user's operation is performed in the same order as in FIG. 6A, and “(1) Document setting on the image reading unit 16” is used as a trigger of the image forming unit 18. In the case where the operation (preheating of the fixing device) is started, the temperature (= T ₂ ) of the fixing device at the time of starting the preheating is higher than the temperature (= T ₁ ) in the example of FIG. T ₂ > T ₁ ), so that the fixing device is operated during the period from when the temperature of the fixing device reaches the image forming temperature T _F until the operation of “(5)“ Copy ”processing execution instruction” is performed by the user. In order to maintain this temperature at the image forming temperature _TF , wasteful power consumption occurs.

  Therefore, in the present embodiment, while the image forming apparatus 10 is in the sleep mode, the CPU 54 monitors whether or not a document has been set on the automatic document feeding unit of the image reading unit 16 based on the document detection signal PAPER. And a process for monitoring whether or not the cover of the platen glass is opened and closed based on the cover open / close detection signal COVER, and whether or not a USB memory or the like is connected to the image forming apparatus 10 is input from the host I / F circuit 70. And a process of monitoring based on each signal. Then, if any of the setting of the original on the automatic document feeder, the opening / closing of the platen glass cover, the connection of the USB memory, etc. is detected, the CPU 54 indicates as “preheating preparation mode” in FIG. In addition, the sleep signal SLEEP_ON, the image forming unit ON signal IOT_ON, and the preheating preparation signal P_HEAT are switched to signal states corresponding to ON, respectively, and the image forming unit 18 (MCU 40) is started to preheat the image forming apparatus 10. Transition to preparation mode.

  Note that the above-mentioned “setting of the document to the automatic document feeder”, “opening / closing the platen glass cover”, and “connection of USB memory” are events that are likely to be performed using the fixing device. The above process is an example of a process performed by the estimation unit according to the present invention, which “guesses whether or not a process using a fixing device is executed”.

  In addition, the MCU 40 of the image forming unit 18 whose operation has been started executes the program stored in the storage unit 40B, thereby performing the on-time processing of the image forming unit shown in FIG. This on-image processing is an example of processing by the control unit according to the present invention.

In the image forming unit ON process, first, in step 80, it is determined whether or not the preheating preparation signal P_HEAT input from the controller 12 is in a signal state corresponding to ON. If the determination is negative, the process proceeds to step 94, and the fixing unit ON signal FSR_ON output to the fixing unit 42 is switched from the signal state corresponding to OFF to the signal state corresponding to ON, whereby the fixing device by the heating unit 48 is operated. Start heating (preheating). If the determination in step 80 is affirmative, it means that any of the setting of the document to the automatic document feeder, the opening and closing of the platen glass cover, and the connection of the USB memory is detected. The current temperature T of the fixing device detected by the temperature sensor 46 of the fixing unit 42 is acquired from the temperature sensor 46. In the next step 84, based on the deviation between the current temperature T of the fixing device acquired in step 82 and the image forming temperature T _F , a preheating time t for raising the temperature of the fixing device to the image forming temperature T _F is set. Calculate. The preheating time t is an example of the required time in the present invention.

  In the next step 86, an estimated time tm until the start of processing execution is instructed by the user is acquired. As the estimated time tm, a preset time (for example, an average operation time required for the user to perform the operations (2) to (5) described above) can be used. When the event detected by the user is “setting the document on the automatic document feeder” or “opening / closing the platen glass cover”, the process instructed to be executed by the user is the “copy” process. When the event is “USB memory connection”, the process instructed to be executed by the user is the “print” process, and the time required for specifying the processing content in (4) according to the type of process (average time) Etc.) may change, and the value of the estimated time tm may be switched according to the type of event detected by the CPU 54 of the controller 12.

In step 88, it is determined whether or not the preheating time t calculated in step 84 is shorter (shorter) than the estimated time tm acquired in step 86. If the determination is negative, the process proceeds to step 94, and the fixing unit ON signal FSR_ON is switched from the signal state corresponding to OFF to the signal state corresponding to ON to start heating (preheating) of the fixing device by the heating unit 48. Let If the determination at step 88 is affirmative, the routine proceeds to step 90, where a time after the current time is calculated as the preheating start time t _S by a time corresponding to the difference between the estimated time tm and the preheating time t. . In the next step 92, it is determined whether or not the preheating start time t _S calculated in step 90 has arrived, and step 92 is repeated until the determination is affirmed.

When the preheating start time t _S arrives, the determination at step 92 is affirmed and the routine proceeds to step 94, where the fixing unit ON signal FSR_ON is switched from the signal state corresponding to OFF to the signal state corresponding to ON, thereby heating unit 48. Start heating (preheating) of the fuser. At this time, the post-processing device ON signal FIN_ON may be switched from the signal state corresponding to OFF to the signal state corresponding to ON. In step 96, the current temperature T of the fixing device is acquired from the temperature sensor 46, and in the next step 98, it is determined whether or not the current temperature T of the fixing device acquired in step 96 is equal to or higher than the image forming temperature _TF. . If the determination is negative, the process returns to step 96, and steps 96 and 98 are repeated until the determination of step 98 is affirmed. If the determination in step 98 is affirmative, the process proceeds to step 100 to notify the controller 12 that the preheating of the fixing unit has been completed, and the processing when the image forming unit is on ends.

By the above process, as shown in FIG. 6C as an example, the preheating of the fixing device is completed approximately at the same time when the user performs an operation to instruct the execution of the process (5). It is possible to start the process instructed to execute without causing the user to wait for a long time. Further, since the preheating time t is calculated based on the current temperature T of the fixing device, as shown in FIG. 6D as an example, when the temperature of the fixing device is relatively high (T = T ₂ ), the preheating of the fixing device is completed approximately at the same time when the user performs the operation to instruct the execution of the process (5), and the temperature of the fixing device is set to the image forming temperature T. It is possible to prevent wasteful power consumption for maintaining _F.

  Note that the above-mentioned “setting of the document to the automatic document feeder”, “opening / closing the platen glass cover” and “connecting the USB memory etc.” are events in which the processing using the fixing device is highly likely to be executed. If there is a user who wants to execute the “scan” process (a process that does not use the fuser) for “loading the document to the automatic document feeder” and “opening / closing the platen glass cover” Is also an operation performed. Therefore, when “scan” is selected by the user in (3), the CPU 54 of the controller 12 shifts the image forming apparatus 10 to the reading unit on mode, and outputs the image forming unit on signal IOT_ON and the preheating preparation signal P_HEAT. Each is switched to a signal state corresponding to OFF, and the image reading unit ON signal IIT_ON is switched to a signal state corresponding to ON.

  In this case, the MCU 40 of the image forming unit 18 terminates the execution of the image forming unit ON process (FIG. 5) triggered by the image forming unit ON signal IOT_ON being switched to a signal state corresponding to OFF. By switching the ON signal FSR_ON to a signal state corresponding to OFF, the operation of the image forming unit 18 is stopped after preheating (heating) of the fixing device is finished. Thereby, useless power consumption is suppressed. The above processing is an example of the invention described in claim 4.

  In the above description, the mode in which the current temperature T of the fixing device is acquired and the preheating time t is calculated based on the acquired temperature T has been described. However, the present invention is not limited to this. The time elapsed since the heating of the fixing device is stopped or estimated, the current temperature T of the fixing device is estimated based on the time measured or the estimated elapsed time, and the preheating time t is calculated based on the estimated temperature T. You may make it calculate. Further, in estimating the current temperature T of the fixing device, the temperature inside the image forming apparatus 10 may be taken into consideration.

  In the above description, a mode in which a preset time (value) is used as the estimated time tm until the start of processing execution is instructed by the user has been described. However, the present invention is not limited to this. In each image forming apparatus 10, the time from when an operation is started to the image forming apparatus 10 in the sleep mode until the execution of processing is instructed is measured, and the average value of the measured times is calculated ( If the configuration authenticates the user, the average value of the measurement time may be calculated for each user).

  Also, in the above, on the premise that the fixing unit is heated by the heating unit 48 composed of a heater or the like (that is, the preheating time t is relatively long), the “document setting on the automatic document feeding unit” or the “platen glass cover” In the above description, the control according to the present invention is performed mainly for the purpose of eliminating the waiting time when the operation of “opening / closing” and “connecting USB memory” is performed first. However, the present invention is not limited to this. For example, in the configuration in which the fixing device is heated by induction heating, the preheating time t is relatively short and the waiting time hardly occurs. Therefore, it is used mainly for the purpose of suppressing wasteful power consumption. The control according to the present invention may be performed regardless of the user's operation order.

  In the above description, the power saving control program, which is an example of the control program for the image forming apparatus according to the present invention, is stored in the flash memory 64, and the image forming unit control program is stored in the storage unit 40B. The control program for the image forming apparatus according to the invention can be provided in a form recorded on a recording medium such as a CD-ROM or a DVD-ROM.

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Controller 18 Image forming part 32 Document set detection switch 36 Cover opening / closing detection switch 42 Fixing part 46 Temperature sensor 48 Heating part 50 Control part

Claims (5)

Heating means for heating the fixing device;
Temperature detecting means for detecting the temperature of the fixing device;
A guessing means for guessing whether or not processing using the fixing device is executed;
While the process using the fixing unit is not being executed and the process using the fixing unit is not estimated to be executed by the estimation unit, heating of the fixing unit by the heating unit is stopped, When it is estimated that the process using the fixing unit is executed by the estimation unit, the temperature of the fixing unit detected by the temperature detection unit or the heating of the fixing unit by the heating unit is stopped. The fixing by the heating unit is performed at a timing corresponding to a required time from the start of heating of the fixing unit by the heating unit until the temperature of the fixing unit reaches a preset temperature. Control means for performing control to start heating of the vessel;
An image forming apparatus including:   The control means estimates the required time based on a temperature of the fixing device detected by the temperature detecting means or an elapsed time since heating of the fixing device by the heating means is stopped, and the fixing The image forming apparatus according to claim 1, wherein heating of the fixing unit by the heating unit is started at a timing before the required time estimated from a scheduled start time of use of the unit. An image reading unit that reads an image of a set document;
Detecting means for detecting at least one of setting of an original on the image reading unit and an operation for reading an image of the original on the image reading unit;
Further comprising
The estimation unit uses the fixing unit when at least one of setting of a document on the image reading unit and an operation for reading an image of a document on the image reading unit is detected by the detection unit. Guess that the process will be executed,
The control means detects at least one of setting of a document on the image reading unit and an operation for reading an image of the document by the image reading unit as the scheduled start time of use of the fixing device. The image forming apparatus according to claim 1, wherein a time after a preset time is used. It further comprises a specifying means for the user to specify the process to be executed,
The control means detects at least one of setting an original on the image reading section and an operation for reading an image of the original on the image reading section by the detecting means, and uses the fixing device by the estimating means. It is presumed that the processing to be performed is performed, and after starting the heating of the fixing device by the heating means, the processing that does not use the fixing device is designated through the designating means as the processing to be executed. The image forming apparatus according to claim 3, wherein heating of the fixing device by the heating unit is stopped. A computer built in the image forming apparatus, comprising: a heating unit that heats the fixing unit; and a temperature detection unit that detects a temperature of the fixing unit.
Inference means for estimating whether or not processing using the fixing device is executed,
And while the process using the fixing device is not being executed and the process using the fixing device is not estimated to be executed by the estimating means, heating of the fixing device by the heating means is stopped. When it is estimated that the process using the fixing unit is executed by the estimation unit, the temperature of the fixing unit detected by the temperature detection unit or the heating of the fixing unit by the heating unit is stopped. By the heating means at a timing according to the time required from the start of heating of the fixing device by the heating means until the temperature of the fixing device reaches a preset temperature, which is obtained from the elapsed time since A control program for an image forming apparatus for functioning as control means for performing control for starting heating of the fixing device.

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