JP5983002B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an improvement in fixing operation in an image forming apparatus having a fixing unit that fixes a toner image formed on a sheet by electrophotography with heat.

  In an electrophotographic image forming apparatus, a toner image is formed on an image bearing member of a rotating photosensitive drum or photosensitive belt, the formed toner image is directly or indirectly transferred onto a sheet, and the toner image is further transferred. An image is formed by fixing on a sheet.

  In this image formation, the toner image electrostatically transferred onto the paper is fixed on the paper in a stable state by heat and pressure from the fixing roller.

  In this fixing, the fixing roller is controlled to be heated within a preset temperature range so that stable fixing can be performed according to the assumed paper type.

  An image forming apparatus provided with this type of fixing device has been proposed in Patent Document 1 below.

JP 2006-64919 A

  In Patent Document 1 described above, there are two stages of (low fixing temperature) / (high fixing temperature) within a preset fixing temperature range. When productivity is prioritized, control is performed so that image output can be started when a low fixing temperature is reached. On the other hand, when priority is given to image quality, control is performed so that image output can be started after reaching a high fixing temperature. In this way, both productivity and quality can be achieved within a fixing temperature range having a certain width.

  In the image forming apparatus, a fixing temperature range is determined so that there is no problem even if image formation is performed stably for a long time on various types of paper (paper within specifications) that are assumed to be used. Yes.

  However, fixing may not be performed sufficiently by using paper that is out of specifications such as a thickness, a surface processing state, and a coating state that are out of the expected range. For example, in the case of a paper having an unexpected thickness or surface processing state, there is a possibility that the heat of the fixing roller is not sufficiently transmitted to the toner on the paper surface and fixing is not performed properly.

  However, in such a case, there is a problem that the conventional image forming apparatus or the image forming apparatus described in Patent Document 1 cannot cope with it.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of appropriately fixing a sheet out of specification.

  The present invention for solving the above-described problems is as follows.

In this image forming apparatus, an image forming unit that transfers a toner image corresponding to image data onto a sheet, a fixing unit that fixes the toner image on the sheet by heat from a heat source, and a temperature that detects the temperature of the fixing unit. a sensor, a control unit for controlling the fixing temperature of the fixing unit based on the detection result of the temperature sensor to control the image formation of said image forming portion, the first fixing temperature is a fixing temperature for the paper in the specification A temperature range including a lower limit value and an upper limit value, and a receiving unit that receives a setting with a second fixing temperature that is a fixing temperature higher than the upper limit value as the fixing temperature, and the control unit includes the receiving unit When the setting of the second fixing temperature is received, fixing at the second fixing temperature is executed under a certain condition.
Further, in this image forming apparatus, an image forming unit that transfers a toner image corresponding to image data to a sheet, a fixing unit that fixes the toner image to the sheet by heat from a heat source, and image formation of the image forming unit And a control unit that controls the fixing temperature of the fixing unit, and an operation display unit that accepts setting input and displays various information, and the control unit is set for the fixing unit. The temperature range of the first fixing temperature that is the fixing temperature for the paper within the specifications includes a lower limit value and an upper limit value, and fixing at the second fixing temperature that is a fixing temperature higher than the upper limit value is performed under a certain condition. And when the setting of the second fixing temperature is received via the operation display unit, the influence caused by the second fixing temperature is displayed on the operation display unit.
Further, in this image forming apparatus, an image forming unit that transfers a toner image corresponding to image data to a sheet, a fixing unit that fixes the toner image to the sheet by heat from a heat source, and image formation of the image forming unit And a control unit that controls the fixing temperature of the fixing unit, and an operation display unit that accepts setting input and displays various information, and the control unit is set for the fixing unit. The temperature range of the first fixing temperature that is the fixing temperature for the paper within the specifications includes a lower limit value and an upper limit value, and fixing at the second fixing temperature that is a fixing temperature higher than the upper limit value is performed under a certain condition. When the image forming setting after the fixing at the second fixing temperature is received or when the image forming is executed after the fixing at the second fixing temperature is completed, 2 According to fixing temperature Fixing is displayed on the operation display unit that has been performed, characterized in that.

  Further, in the above image forming apparatus, the control unit, as the certain condition, when either the number of sheets on which the image is formed or the time for forming the image exceeds a predetermined condition, The setting of the second fixing temperature is canceled.

  Further, in the above image forming apparatus, the control unit does not start fixing at the second fixing temperature when an in-machine temperature in the fixing unit is equal to or higher than a predetermined value. To do.

  Further, in the above image forming apparatus, the control unit does not execute fixing at the next second fixing temperature until a predetermined time elapses after the fixing at the second fixing temperature is completed. To do.

  The image forming apparatus includes an operation display unit that receives setting input and displays various information, and the control unit receives the setting of the second fixing temperature via the operation display unit. The operation display unit displays an effect caused by the second fixing temperature.

Further, the above image forming apparatus includes an operation display unit that accepts input of settings and displays various information, and the control unit accepts settings for image formation after the fixing at the second fixing temperature is completed. Alternatively, when the image is formed after the fixing at the second fixing temperature is completed, the fact that the fixing at the second fixing temperature has been performed is displayed on the operation display unit. To do.
In the above image forming apparatus, the control unit determines whether the second fixing temperature exceeds a fixing upper limit temperature attributed to the image forming apparatus or a fixing upper limit temperature attributed to the sheet, and the image. At least the image forming time and the number of images formed as the predetermined condition when the second fixing temperature does not exceed the upper fixing temperature due to the forming device or the upper fixing temperature due to the paper, the image forming device The upper limit temperature caused by the above or the upper limit temperature caused by the sheet is more restrictive than when the second fixing temperature exceeds the upper limit temperature.

  According to the above invention, the following effects can be obtained.

In this image forming apparatus, the second fixing temperature, which is a fixing temperature higher than the upper limit of the fixing temperature set for the fixing unit, is used when the toner image is fixed on the paper by heat from a heat source during image formation. In order to perform fixing at a certain condition, when non-specification paper such as thickness, surface processing condition, coating condition outside the expected range is used, it is also appropriate for non-specification paper. It becomes possible to fix.

  In addition, as a fixed condition, when either the number of sheets on which image formation is performed or the time for image formation exceeds a predetermined condition, the setting of the second fixing temperature is canceled, so that the normal fixing temperature is set. Even if the second fixing temperature exceeds the above range, stable operation is possible without adversely affecting the apparatus.

  The controller does not start fixing at the second fixing temperature when the in-machine temperature in the fixing unit is equal to or higher than a predetermined value, so that the second fixing temperature is not affected adversely to the apparatus. Operation becomes possible.

  In addition, since the next fixing at the second fixing temperature is not executed until a predetermined time has elapsed after the fixing at the second fixing temperature is completed, the second fixing temperature can be operated in a situation where the apparatus is not adversely affected. become.

  Further, since the influence caused by the second fixing temperature is displayed when accepting the setting of the second fixing temperature via the operation display unit, the operation of the second fixing temperature is possible in a state in which the expected influence is announced. .

  Further, when accepting the setting of image formation after the fixing at the second fixing temperature is completed, or at the time of image formation executed after the fixing at the second fixing temperature is completed, the fixing at the second fixing temperature is performed until then. Therefore, the operation at the second fixing temperature is possible in a state in which the expected influence is announced.

It is a block diagram which shows schematic structure of embodiment of this invention. It is a flowchart which shows operation | movement of embodiment of this invention. It is explanatory drawing which shows the display state of the operation display part in embodiment of this invention. It is explanatory drawing which shows the display state of the operation display part in embodiment of this invention. It is explanatory drawing which shows the display state of the operation display part in embodiment of this invention. It is explanatory drawing which shows the display state of the operation display part in embodiment of this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments (embodiments) for carrying out an image forming apparatus of the present invention will be described below in detail with reference to the drawings.

〔Constitution〕
Here, the configuration of the electrophotographic image forming apparatus 100 according to the first embodiment will be described in detail with reference to FIG. Note that descriptions of general parts that are known as the image forming apparatus 100 and are not directly related to the characteristic operations and controls of the present embodiment are omitted.

  An image forming apparatus 100 shown in FIG. 1 includes a control unit 101 that controls each unit, an operation display unit 105 in which an operator inputs various operations and performs various displays, a storage unit 110 that stores job data and various data, a document A scanner 120 that generates image data by reading image data, an image processing unit 130 that performs predetermined image processing on image data to be imaged, and a print engine 140 that forms an image on paper based on the image data. ing.

  The control unit 101 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (not shown). Here, the CPU uses a predetermined area of the RAM as a work area, executes various programs stored in the ROM, and comprehensively controls each unit of the image forming apparatus 100. In addition, as will be described later, the control unit 101 executes control related to the second fixing temperature shown in the flowchart.

  Here, the operation display unit 105 includes input devices such as a keyboard, a mouse, and a touch panel, and transmits various input instruction signals to the control unit 101. The operation display unit 105 includes display means such as an LCD (Liquid Crystal Display) and a CRT (Cathode Ray Tube), and displays various image data input from the control unit 101. The operation display unit may be provided separately from the operation unit. However, since a touch panel that presses a displayed icon, key, or button is generally used, in the following embodiment, a touch panel type operation is performed. The description will be made assuming that the display unit 105 is used.

  The storage unit 110 is a storage device such as an HDD (Hard Disc Drive) or a flash memory in which data can be freely written, erased, and read, and may be provided in a fixed manner or attached and detached. It may be provided freely. The storage unit 110 stores job data including one or more registered jobs (including processed, processed, and unprocessed jobs). Furthermore, the storage unit 110 stores information regarding the replacement date of each component and the relationship between the components for adjustment control during component replacement.

  The print engine 140 is transferred onto a sheet by an image forming unit 142 that transfers a toner image according to image data onto a sheet through processes such as charging, exposure (latent image formation), development, and transfer by electrophotography. And a fixing unit 144 that fixes the toner image on the paper in a stable state by heat and pressure generated by the fixing roller.

  Here, as a heat source for heating the fixing roller in the fixing unit 144, various heat sources such as a halogen heater and an IH heater can be used. Further, since the structure of the fixing unit 144 and the principle of fixing are well known, detailed description thereof is omitted.

  Note that the in-machine temperature in the print engine 140, the in-machine temperature in the fixing unit 144, or the temperature of the fixing roller in the fixing unit 144 is detected by a temperature sensor (not shown), and the detection result is notified to the control unit 101. .

[Prerequisites]
Hereinafter, the preconditions of the present embodiment will be described in relation to the fixing temperature. Here, the fixing temperature means a surface temperature of a fixing roller which is a member that performs fixing in the fixing unit 144.

・ Fusing upper limit temperature Tmachine due to the device:
If the fixing temperature exceeds Tmachine, a problem such as a failure of the fixing unit 144 may occur. It is a fixed value by the device.

・ Fixing upper limit temperature Tpaper caused by paper:
If the fixing temperature exceeds Tpaper, a defect may occur in the paper or the image on the paper. It depends on the paper type.

Normal fixing temperature (first fixing temperature) T1:
Conventionally, a general fixing temperature that is generally determined so that there is no problem even if image formation is performed stably for a long time on various types of paper that are assumed to be used (paper within specifications). The lower limit value of the fixing temperature T1 is T1min, and the upper limit value of the fixing temperature T1 is T1max. T1max is determined so as not to exceed Tmachine or Tpaper, whichever is lower.

Fixing temperature (second fixing temperature) T2 higher than normal (T1min to T1max):
Temporary image formation is possible on non-specification paper, and the fixing temperature is higher than the usual normal fixing temperature. The upper limit value of the second fixing temperature T2 is T2max. Note that T2max is set within a range that does not cause a problem in the image forming apparatus under certain limited conditions such as the image forming time and the number of images formed. Image forming device failure here refers to a situation where repair or maintenance is required, such as a failure of the fixing device (such as the rubber on the fixing roller being peeled off), melting of the toner in the developing device due to a rise in the temperature inside the device, failure of various sensors, etc. Means.

In addition, when the relationship between the above T1 and T2 is summarized,
T1mini <T1 <T1max <T2 <T2max,
It can be expressed as

In addition, the control unit 101
・ Set the second fixing temperature T2 under certain conditions.
The setting of the second fixing temperature T2 is canceled when either the number of sheets on which the image is formed or the time for forming the image exceeds a predetermined condition as a fixed condition.
When the temperature inside the fixing unit 144 is equal to or higher than a predetermined value, fixing at the second fixing temperature T2 is not started.
The fixing at the next second fixing temperature T2 is not executed until a predetermined time has elapsed after the fixing at the second fixing temperature T2 is completed.
When receiving the setting of the second fixing temperature T2, the operation display unit 105 displays an influence that may be caused by the second fixing temperature T2.
The second fixing temperature T2 until then when the setting of image formation after the fixing at the second fixing temperature T2 is accepted or when the image forming is executed after the fixing at the second fixing temperature T2 is completed. Display on the operation display unit 105 that the fixing by
Such control is performed.

[Operation]
Hereinafter, the operation of the image forming apparatus according to the present embodiment will be described with reference to the flowchart of FIG. 2 and the screen explanatory diagrams of FIG. Here, an operation in the case where fixing is performed on the out-of-specification sheet at the second fixing temperature T2 will be described.

  The control unit 101 displays a setting screen 1050A (see FIG. 3) on the operation display unit 105 during standby. On the setting screen 1050A, the operator who wants to form an image with a sheet out of specification clicks the sheet setting key 1050a1 with a pointing device or the like.

  The control unit 101 that has received a paper setting operation from the setting screen 1050 </ b> A in the operation display unit 105 displays a setting screen 1050 </ b> B for paper setting in FIG. 4 on the operation display unit 105. With this sheet setting setting screen 1050B, settings such as sheet type, profile name, sheet size, basis weight, color, punch hole presence, front and back image formation position adjustment, and the like can be made for each tray.

  In the setting screen 1050B of FIG. 4, an example of setting for the tray 1 is shown. Here, the paper type can be selected from plain paper, high-quality paper, color paper, coated paper (coated paper GL, coated paper ML, coated paper GO, coated paper MO), and the like. Further, if the paper size is a standard size, it can be automatically detected by placing it on a tray. As the basis weight, a settable range is determined according to the paper type. As the process adjustment, the temperature setting range for the first fixing temperature T1 is determined according to the paper type and the basis weight.

  In this embodiment, a sheet outside the specification can be fixed at the second fixing temperature T2 that is higher than the normal fixing temperature, and a sheet within the specification is fixed at the normal first fixing temperature T1. .

  Accordingly, the setting item of “high-temperature fixing mode” indicated by 1050b1 in FIG. 4 is “None” as an initial value for normal paper, and is indicated by 1050b2 in FIG. Thus, “Yes” is changed (step S100 in FIG. 2).

  When the paper setting is completed on the setting screen 1050B, the operator clicks “OK” on the lower right of the setting screen 1050B to save each paper profile name and handle it with reference to the paper profile name in the future. It becomes possible.

  When the paper setting is completed on the setting screen 1050B, the control unit 101 returns the display of the operation display unit 105 from the setting screen 1050B to the setting screen 1050A.

  When the operator clicks the “high temperature fixing mode setting” key 1050a2 on the lower right of the setting screen 1050A in FIG. 3 with the cursor 1050a3, the control unit 101 sets the sheet for which the setting of the high temperature fixing mode is “Yes”. 5 is displayed as a display screen of the operation display unit 105 in a high-temperature fixing mode setting screen 1050C shown in FIG. The operator performs detailed setting of the second fixing temperature T2 via the high-temperature fixing mode setting screen 1050C (step S101 in FIG. 2).

  Here, the operator selects a paper type to be fixed at the second fixing temperature T2 as the setting of the high-temperature fixing mode (step S102 in FIG. 2, 1050c1 in FIG. 5).

  In the example of the setting screen 1050C in FIG. 5, plain paper and coated paper are displayed as options. However, as the paper type options, the types of high quality paper / medium quality paper and coated paper are increased. Also good. Also, since the paper is out of specification or unexpected, a new paper type option may be provided.

  Upon receiving this paper type setting information, the control unit 101 sets the upper limit value T1max of the first fixing temperature T1 at the maximum basis weight corresponding to the corresponding paper type and the second fixing temperature T2 as many times as T1. Displays whether it can be raised. Here, the difference between the upper limit value T2max of the second fixing temperature T2 and the upper limit value T1max of the first fixing temperature T1 is displayed as an adjustment range (1050c2 in FIG. 5).

  If the high temperature fixing mode setting item 1050b1 in FIG. 4 is not provided, the adjustment range 1050c2 of the second fixing temperature T2 in FIG. You may make it display.

  The operator refers to this adjustment range and sets how many times the temperature is actually raised as the high-temperature fixing mode (step S103 in FIG. 2). In the case of FIG. 5, when the adjustment range is + 20 ° C., it is set to + 10 ° C. (1050c3 in FIG. 5).

  Note that when the control unit 101 receives the setting of the second fixing temperature T2 on the high-temperature fixing mode setting screen 1050C, the control unit 101 may have an influence that may be caused by the second fixing temperature T2 higher than the first fixing temperature T1, for example, the image quality. Reduction, uneven gloss, paper curl, high temperature offset (adhesion of molten toner to the fixing roller), poor separation, and the like are displayed as important matters to the operator (1050c4 in FIG. 5). In addition, as an influence displayed here, you may change a display according to importance.

  Then, the operator who has set how many times to actually raise as the high-temperature fixing mode presses an OK button (1050c5 in FIG. 5) to confirm the operation (YES in step S104 in FIG. 2). When the set temperature exceeds the adjustment range, the control unit 101 deactivates the OK button, returns the set value (1050c3 in FIG. 5) to 0, and re-operates the operator. (NO in step S104 in FIG. 2, step S102).

  Here, the control unit 101 determines whether the second fixing temperature T2 is equal to or higher than the fixing upper limit temperature Tmachine (step S105 in FIG. 2).

  If the second fixing temperature T2 is equal to or higher than the fixing upper limit temperature Tmachine (YES in step S105 in FIG. 2), a malfunction such as a failure in the fixing unit 144 may occur. For this reason, the control unit 101 determines a condition in which the number of sheets on which images are formed and the image forming time are limited as a certain condition within a range in which no malfunction occurs (step S106 in FIG. 2). For example, if the number of sheets is within 150 sheets or the image forming time of 5 minutes is exceeded, whichever is smaller, the control unit 101 sets a strict limit such as releasing the second fixing temperature T2.

  Further, when the second fixing temperature T2 is not equal to or higher than the fixing upper limit temperature Tmachine (NO in step S105 in FIG. 2), there is little possibility that a malfunction such as a failure in the fixing unit 144 occurs. However, since the temperature is higher than the normal first fixing temperature T1, the control unit 101 is loosely limited in terms of the number of sheets on which images are formed and the image forming time as a constant condition for avoiding a continuous state for a long time. The condition of the state is determined (step S107 in FIG. 2). For example, when the number of sheets is less than 500 sheets or the image forming time of 30 minutes, whichever is smaller, the control unit 101 sets a loose restriction such as releasing the second fixing temperature T2. In the case where a large margin is set when determining the first fixing temperature T1, the loose restriction in step S107 may actually be unlimited.

  In the above step S105, Tmachine is used as a determination criterion, but the restriction may be determined using Tpager as a determination criterion.

  In addition, as a restriction on the constant condition by the second fixing temperature T2, it is desirable that the control unit 101 calculates by calculation according to the value determined in step S103. For example, even when T2 ≧ Tmachine, the effect on the fixing unit 144 differs when the temperature exceeds 1 ° C. and when the temperature exceeds 10 ° C. Therefore, the limit may be changed according to the expected impact. desirable.

  In this way, when the second fixing temperature T2 is determined and the limitation at the time of executing the second fixing temperature T2 is determined, the control unit 101 sets the limitation content as the high-temperature fixing mode setting screen 1050D. The contents are displayed and notified to the operator (1050d1 in FIG. 6).

  Then, by pressing the “Yes” button (1050d2 in FIG. 6) on the high-temperature fixing mode setting screen 1050D, the operator can start the high-temperature fixing mode (YES in step S108 in FIG. 2).

  At the time of starting the high-temperature fixing mode, the control unit 101 refers to the detection result of the temperature sensor, and when the inside of the fixing unit 144 is in the normal temperature range (YES in step S109 in FIG. 2), the high-temperature fixing is performed. The mode is activated (step S110 in FIG. 2).

  That is, when the temperature inside the fixing unit 144 is higher than a predetermined value (NO in step S109 in FIG. 2), in order to prevent continuous accumulation of thermal stress in the fixing unit 144, Without executing the high-temperature fixing mode, the apparatus waits until the temperature inside the fixing unit 144 falls to the normal range.

  Here, the operator sets or inputs an image forming job via the operation display unit 105 (step S111 in FIG. 2). At this time, the control unit 101 determines whether or not the setting of the input image forming job falls within the above limit range (step S112 in FIG. 2).

  If the setting of the input image forming job does not fall within the above limit range (NO in step S112 in FIG. 2), the control unit 101 determines whether to execute only the part within the limit range. An inquiry is made to the operator via a setting screen (not shown) (step S113 in FIG. 2).

  When the setting of the input image forming job does not fall within the above limit range (NO in step S112 in FIG. 2), and the operator does not agree to execute only the portion within the limit range (in FIG. 2) In step S113, NO), the control unit 101 returns to the job input (step S111 in FIG. 2). When the input image forming job setting does not fall within the above limit range (NO in step S112 in FIG. 2), but the operator agrees to execute only the portion within the limit range (in FIG. 2) In step S113, the control unit 101 sets the number of images to be formed within the limit range (step S114 in FIG. 2).

  When the input image forming job setting falls within the above limit range (YES in step S112 in FIG. 2), or when the number of image forming sheets is set within the limit range (step S114 in FIG. 2) The control unit 101 drives the heat source while referring to the detection result of the temperature sensor, and confirms whether the fixing roller in the fixing unit 144 has reached the second fixing temperature T2 (step S115 in FIG. 2).

  When the fixing roller in the fixing unit 144 reaches the second fixing temperature T2 by driving the heat source while referring to the detection result of the temperature sensor, the control unit 101 executes the input image forming job, Image processing in the image processing unit 130, image formation in the image forming unit 142 (formation of a toner image on the paper), and fixing in the fixing unit 144 (fixing of the toner image on the paper) are executed (FIG. 2). Middle step S116).

  When the executed job is completed, or when the job being executed reaches the limit due to the image formation time or the like (YES in step S117 in FIG. 2), the control unit 101 ends the high-temperature fixing mode (second fixing). The setting of the temperature T2 is canceled), and the fixing roller in the fixing unit 144 is controlled to return to the first fixing temperature T1 (step S118 in FIG. 2). Note that although the control unit 101 has started image formation so as to fall within the limit range in steps S112 to S114, this step S117 corresponds to the case where the image formation time or the like is longer than expected.

  In this case, the image formation may be continued from the second fixing temperature T2 to the first fixing temperature T1, but the image formation itself may be controlled to be stopped as desired by the operator.

  Thereafter, the control unit 101 passes a predetermined time after the high-temperature fixing mode is finished in order to reduce the influence of the stress due to the heat of the fixing unit 144 or to prevent the accumulation of the stress due to the heat of the fixing unit 144. Until this is done, it is prohibited to execute the high-temperature fixing mode again (step S119 in FIG. 2). In addition, it is desirable to determine this fixed time according to the second fixing temperature T2.

  Further, the control unit 101 receives an image formation setting after the fixing at the second fixing temperature T2 is completed, or at the time of image formation executed after the fixing at the second fixing temperature T2 is completed. The fact that the high-temperature fixing at the second fixing temperature T2 has been performed may be displayed as reference information on the display screen of the operation display unit 105. In this case, it is also desirable to notify the expected influence on the display screen of the operation display unit 105 because the fixing unit 144 is or is higher than the normal first fixing temperature T1. .

  In the image forming apparatus of the above embodiment, the second fixing temperature T2 that exceeds the upper limit of the normal first fixing temperature T1 set for the fixing unit 144 is executed under a certain condition. When a sheet outside the specifications such as the outside thickness, surface processing state, and coating state is used, it is possible to appropriately fix the sheet outside the specifications.

  In addition, as a certain condition, when either the number of sheets on which images are formed or the time for image formation exceeds a predetermined condition, the setting of the second fixing temperature T2 is canceled, Even at the second fixing temperature T2 exceeding the range of the first fixing temperature T1, stable operation is possible without adversely affecting the apparatus.

  Further, when the internal temperature in the fixing unit 144 is equal to or higher than a predetermined value, the control unit 101 does not start fixing at the second fixing temperature T2, and thus does not adversely affect each part of the apparatus. Operation at the second fixing temperature T2 becomes possible.

  In addition, since the fixing at the next second fixing temperature T2 is not executed until a predetermined time has elapsed after the fixing at the second fixing temperature T2 is completed, the second fixing temperature T2 in a situation that does not adversely affect each part of the apparatus. Can be operated.

  In addition, when the setting of the second fixing temperature T2 is received via the operation display unit 105, the influence caused by the second fixing temperature T2 is displayed. Operation at temperature T2 becomes possible.

  Further, when accepting the setting of image formation after the fixing at the second fixing temperature T2 is completed, or at the time of image forming executed after the fixing at the second fixing temperature T2 is completed, the second fixing temperature is used until then. Since the fact that the fixing by T2 has been performed is displayed, the operation at the second fixing temperature T2 becomes possible in a state where the expected influence is notified to the operator.

[Other Embodiments]
In FIG. 1, the image forming apparatus 100 has been described on the assumption that a normal fixing unit 144 is used. However, the present invention is not limited to this, and the image forming apparatus 100 is configured to include two fixing units, a first fixing unit and a second fixing unit. In addition, this embodiment can be applied.

  The present embodiment can also be applied to an image forming system using an external fixing device with respect to the image forming apparatus 100.

  Further, the present embodiment can be applied to any of the monochrome image forming apparatus and the color image forming apparatus as the image forming apparatus.

DESCRIPTION OF SYMBOLS 100 Image forming apparatus 101 Control part 110 Storage part 120 Scanner 130 Image processing part 140 Print engine 142 Image formation part 144 Fixing part

Claims (9)

An image forming unit that transfers a toner image corresponding to image data onto a sheet;
A fixing unit for fixing the toner image to the paper by heat from a heat source;
A control unit that controls image formation of the image forming unit and controls a fixing temperature of the fixing unit;
The first fixing temperature range that is the fixing temperature for the sheet within the specification includes a lower limit value and an upper limit value, and accepts a setting for setting the second fixing temperature, which is a fixing temperature higher than the upper limit value , as the fixing temperature. And
With
The control unit executes fixing at the second fixing temperature under a certain condition when the receiving unit receives the setting of the second fixing temperature.
An image forming apparatus. It has an operation display unit that accepts settings and displays various information.
The control unit displays an influence caused by the second fixing temperature in the operation display unit when receiving the setting of the second fixing temperature via the operation display unit.
The image forming apparatus according to claim 1. An image forming unit that transfers a toner image corresponding to image data onto a sheet;
A fixing unit for fixing the toner image to the paper by heat from a heat source;
A control unit that controls image formation of the image forming unit and controls a fixing temperature of the fixing unit;
An operation display unit that accepts input of settings and displays various information;
With
The control unit includes a first fixing temperature range which is set for the fixing unit and is a fixing temperature for a sheet within specifications, including a lower limit value and an upper limit value, and a fixing temperature higher than the upper limit value. run the fixing at the second fixing temperature is under certain conditions,
When receiving the setting of the second fixing temperature via the operation display unit, the influence generated by the second fixing temperature is displayed on the operation display unit;
An image forming apparatus. It has an operation display unit that accepts settings and displays various information.
The controller is
When the setting of image formation after the fixing at the second fixing temperature is received or when the image forming is executed after the fixing at the second fixing temperature is completed, the fixing at the second fixing temperature is performed until then. Is displayed on the operation display unit.
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. An image forming unit that transfers a toner image corresponding to image data onto a sheet;
A fixing unit for fixing the toner image to the paper by heat from a heat source;
A control unit that controls image formation of the image forming unit and controls a fixing temperature of the fixing unit;
An operation display unit that accepts input of settings and displays various information;
With
The control unit includes a first fixing temperature range which is set for the fixing unit and is a fixing temperature for a sheet within specifications, including a lower limit value and an upper limit value, and a fixing temperature higher than the upper limit value. run the fixing at the second fixing temperature is under certain conditions,
Depending on the second fixing temperature until the setting of image formation after the fixing at the second fixing temperature is accepted or when the image forming is executed after the fixing at the second fixing temperature is completed. Display on the operation display section that the fixing has been performed.
An image forming apparatus. The control unit cancels the setting of the second fixing temperature when either the number of sheets on which the image is formed or the time for forming the image exceeds a predetermined condition as the certain condition. ,
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The controller does not start fixing at the second fixing temperature when the in-machine temperature in the fixing unit is equal to or higher than a predetermined value;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The control unit does not execute fixing at the next second fixing temperature until a predetermined time has elapsed after the fixing at the second fixing temperature is completed.
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The control unit determines whether the second fixing temperature exceeds a fixing upper limit temperature caused by the image forming apparatus or a fixing upper limit temperature caused by the paper;
At least the image forming time and the number of images formed as the certain conditions when the second fixing temperature does not exceed the upper fixing temperature due to the image forming apparatus or the upper fixing temperature due to the paper 9. The method according to claim 1, wherein the upper limit temperature of fixing caused by the forming apparatus or the upper limit temperature of fixing caused by the sheet is less restrictive than when the second fixing temperature exceeds the upper limit temperature. The image forming apparatus described.