JP2002175000A - Image forming device - Google Patents

Abstract

(57) [Problem] To provide a heater for preventing dew condensation and a sheet of paper when power supply to a fixing device is cut off when a power supply is turned off or when operation of an apparatus is not performed for a predetermined time. The heater for moisturizing can be turned on, and on / off of the heater for preventing dew condensation and the heater for moisturizing paper can be controlled based on the total power consumption of the device. According to the present invention, a heater for preventing dew condensation and a heater for moisturizing paper are provided when power is turned off or when power supply to a fixing device is cut off due to no operation of a device for a predetermined time. ON, and when the total power consumption of the device is equal to or more than the predetermined power amount, the heater for dew condensation prevention and the heater for moisturizing the paper are turned off, and when the total power consumption of the device is equal to or less than the predetermined power amount, The heater for preventing dew condensation and the heater for keeping the paper moist are turned on.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus having a heater for preventing dew condensation or a heater for moisturizing an image forming medium.

[0002]

2. Description of the Related Art In a conventional image forming apparatus such as a copying machine, a heater for preventing dew condensation and a heater for moisturizing paper are turned on only when the power is off, or always prevent dew condensation regardless of whether the power is on or off. The heater in which the heater for the heater is turned on has been put to practical use.

[0003] However, as a current copying machine, a multifunction machine has been developed, and a machine having a facsimile function (multifunction machine) has been put to practical use.

[0004] In a multifunction peripheral having such a facsimile function, since the power is turned on day and night, it is not possible to use a dew condensation prevention heater which is turned on only when the power is turned off.

Further, when the heater for preventing dew condensation and the heater for keeping the paper moist are always on regardless of whether the power is on or off, there is a disadvantage that the power consumption increases. Further, when the total amount of power is limited, there is a disadvantage that the power consumption becomes a problem.

[0006]

SUMMARY OF THE INVENTION The present invention provides a heater for preventing dew condensation and a sheet of paper when the power supply to the fixing device is cut off when the power is turned off or when the operation of the apparatus is not performed for a predetermined time. Provided is an image forming apparatus capable of turning on a heater for keeping moisture and controlling on / off of a heater for preventing dew condensation and a heater for keeping moisture of paper based on the total power consumption of the device. It is intended to be.

[0007]

SUMMARY OF THE INVENTION The present invention relates to an image forming apparatus which has a heater for preventing dew condensation and forms an image on an image forming medium based on various settings from an operation panel. Control means for controlling on and off of the heater; and a first means for turning on the dew condensation preventing heater by the control means when the power is off, and turning off the dew condensation preventing heater by the control means when the power is on. Processing means, a second processing means for turning on the dew condensation prevention heater by the control means when the setting from the operation panel is not made for a predetermined time or more, and a dew condensation prevention heater by the control means. A third processing unit for turning off a heater for preventing dew condensation by the control unit when a setting is made from the operation panel when the switch is turned on.

According to the present invention, in an image forming apparatus having a heater for preventing dew condensation and forming an image on a medium on which an image is to be formed, the total power consumption of the apparatus is determined to be equal to or less than a predetermined amount of power. There is provided control means for controlling on / off of the heater for preventing condensation.

According to the present invention, there is provided an image forming apparatus having a fixing device for fixing a developer image on an image forming medium by induction heating a heating roller and a heater for preventing dew condensation, and forming an image on the image forming medium. The apparatus further includes a control unit that controls on / off of the dew condensation prevention heater according to whether the power consumption of the fixing device is equal to or less than a predetermined amount of power.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing a schematic configuration of a digital copying machine 1 as an example of an image forming apparatus according to the present invention.

As shown in FIG. 1, the digital copying machine 1 includes an apparatus main body 2, in which a scanner section 4 as reading means and a printer section 6 functioning as image forming means are provided. ing.

On the upper surface of the apparatus main body 2, there is provided an original mounting table 8 made of transparent glass on which an object to be read, that is, an original D is mounted. An automatic document feeder 9 (hereinafter, referred to as an ADF) as a conveying means for automatically feeding the document D onto the document table 8 is provided on the upper surface of the apparatus main body 2.

The document D placed on the document tray 9a of the ADF 9 is transported by a transport guide (not shown) and is discharged onto a paper discharge tray 9c via a platen roller 9b. Thereby, while the original D is being conveyed by the platen roller 9b, the original D is exposed and scanned by the exposure lamp 10 of the scanner unit 4 described later.
The reading of the image of the document D is performed.

The original D is set on the original tray 9a of the ADF 9 with the reading surface of the original D facing upward, and the originals D are taken one by one from the uppermost original D.

The scanner unit 4 provided in the apparatus main body 2
An exposure lamp 10 composed of, for example, a halogen lamp or the like as a light source for illuminating the original D conveyed by the ADF 9 or the original D placed on the original placing table 8, reflects reflected light from the original D in a predetermined direction. First mirror 1 to deflect
2, the exposure lamp 10 and the first mirror 12
Is a first carriage 1 disposed below the document table 8.
4 attached.

The first carriage 14 is arranged so as to be movable in parallel with the original table 8, and is reciprocated below the original table 8 by a scanner motor (drive motor) 16 via a toothed belt or the like (not shown). You. Scanner motor 16
Is constituted by a stepping motor or the like.

A second carriage 18 is provided below the document table 8 so as to be movable in parallel with the document table 8. The second carriage 18 sequentially deflects the reflected light from the document D deflected by the first mirror 12.
And third mirrors 20, 22 are mounted at right angles to each other. The second carriage 18 is driven by the first carriage 14 with the rotation force from the scanner motor 16 transmitted by a toothed belt or the like that drives the first carriage 14, and is driven by the first carriage 14. , Is moved in parallel along the document table 8 at a speed of 1/2.

An image forming lens 24 for converging the reflected light from the third mirror 20 on the second carriage 18 and a light receiving the reflected light converged by the image forming lens 24 are provided below the document table 8. And a CCD sensor (line sensor) 26 for performing photoelectric conversion. The imaging lens 24 is movably disposed via a drive mechanism in a plane including the optical axis of the light deflected by the third mirror 22, and moves the reflected light to a desired magnification ( An image is formed in the main scanning direction). The CCD sensor 26 is connected to a main CP (to be described later).
In accordance with the image processing clock given from U, the reflected light incident on the original is subjected to photoelectric conversion, and an electric signal corresponding to the read original D is output. The magnification in the sub-scanning direction can be handled by changing the transport speed of the ADF 9 or the moving speed of the first carriage 14.

When reading the original D conveyed by the ADF 9, the irradiation position of the exposure lamp 10 is
It is fixed at a reading position (not shown). When reading the document D placed on the document table 8, the irradiation position of the exposure lamp 10 is moved from left to right along the document table 8.

The scanner unit 4 is provided with a heater (dump heater) 81 for preventing dew condensation on the scanner unit 4 and especially on each mirror.

On the other hand, the printer section 6 is provided with a laser exposure device 28 acting as a latent image forming means. The peripheral surface of the photosensitive drum 30 is scanned by the laser beam from the laser exposure device 28 to form an electrostatic latent image on the peripheral surface of the photosensitive drum 30.

The printer section 6 has a rotatable photosensitive drum 30 as an image carrier, which is disposed substantially at the center right of the apparatus main body 2. And a desired electrostatic latent image is formed. On the peripheral surface of the photosensitive drum 30, a charging charger 3 for charging the peripheral surface of the drum to a predetermined charge is provided.
2. a developing unit 34 as a developing unit for supplying toner as a developer to the electrostatic latent image formed on the peripheral surface of the photosensitive drum 30 to develop it at a desired image density;
8 and 50, the image forming medium, that is, the peeling charger 36 for separating the copy sheet P from the photosensitive drum 30 is integrally provided, and the toner image formed on the photosensitive drum 30 is transferred to the sheet P. Charger 3 to transfer to
8, a peeling claw 40 for peeling the copy sheet P from the peripheral surface of the photoconductor drum 30, a cleaning device 42 for cleaning the toner remaining on the peripheral surface of the photoconductor drum 30, and a static eliminator 44 for discharging the peripheral surface of the photoconductor drum 30 Are arranged in order.

Further, a heater (dump heater) 82 for preventing dew condensation around the developing device 34 and the developing device 34 is provided below the developing device 34 in the printer section 6.

An upper cassette 48 and a lower cassette 5 which can be pulled out from the apparatus main body are provided in the lower part of the apparatus main body 2 respectively.
0 are arranged in a stacked state with respect to each other, and each cassette 48, 50
Inside are loaded copy papers P of different sizes.
A manual tray 54 is provided beside the upper cassette 48.

In the vicinity of the cassette 48, a heater (dump heater) 83 for moisturizing the copy sheet P in each of the cassettes 48 and 50 is provided.

In the apparatus main body 2, each cassette 48, 50
And a transfer path 56 extending through the transfer section located between the photosensitive drum 30 and the transfer charger 38. A fixing device 58 is provided at the end of the transfer path 56. An outlet 60 is formed in an upper part of the fixing device 58.

The fixing device 58 includes a heating roller 58b and a pressure roller 58c in which an induction heating device (IH) 58a is housed as a heat source, and the copy sheet P is sandwiched between these rollers to transfer the copy sheet P. While transporting
The developer image on the copy sheet P is fixed by the heat of the heating roller 58b. The copy paper P that has passed through the fixing device 58 is
The sheet is discharged from the discharge port 60 by the sheet discharge roller pair 70.

In the vicinity of the upper cassette 48 and the lower cassette 50, a paper feed roller 62 and a separation roller 63 for taking out the sheets P one by one from the respective cassettes 48 and 50 are provided, respectively. The transport path 56 is provided with a number of paper feed roller pairs 64 for transporting the copy paper P taken out by the paper feed roller 62 and the separation roller 63 through the transport path 56.

A pair of registration rollers 66 is provided upstream of the photosensitive drum 30 in the transport path 56. The registration roller pair 66 corrects the inclination of the copy paper P taken out, aligns the leading end of the toner image on the photosensitive drum 30 with the leading end of the copy paper P, and adjusts the moving speed of the peripheral surface of the photosensitive drum 30 to the speed. The copy paper P is fed to the transfer unit at the same speed. A pre-alignment sensor 68 for detecting the arrival of the copy sheet P is provided in front of the registration roller pair 66, that is, on the side of the sheet supply roller 64.

Each of the cassettes 48, 5
The copy sheets P taken one by one from 0 are sent to a pair of registration rollers 66 by a pair of paper feed rollers 64. Then, the copy sheet P is sent to the transfer section after the leading end is aligned by the pair of registration rollers 66.

In the transfer section, the developer image formed on the photosensitive drum 30, that is, the toner image is transferred onto the paper P by the transfer charger 38. The copy paper P on which the toner image has been transferred is separated from the peripheral surface of the photosensitive drum 30 by the action of the separation charger 36 and the separation claw 40,
A transport belt (not shown) that forms part of the transport path 56
Through the fixing device 58. After the developer image is fused and fixed to the copy sheet P by the fixing device 58, the copy sheet P is discharged from the discharge port 6 by the discharge roller pair 70.
0 is discharged onto the paper discharge tray 72 in the apparatus main body 2.

On the right side of the transport path 56, there is provided an automatic double-sided device 74 for reversing the copy sheet P that has passed through the fixing device 58 and sending it to the transport path 56 again.

An operation panel for instructing various copying conditions such as a copy magnification and starting copying is provided on an upper front portion of the apparatus main body 2.

The internal configuration of the control circuit of the digital copying machine 1 will be described with reference to FIG.

The digital copying machine 1 is provided with a main control section 90 for controlling the whole. This main control unit 90
Are not shown, respectively, are CPs that control the operation thereof.
U (central processing uniti)
t), a ROM (Rend only memory) in which software for operating the digital copying machine 1 is stored.
y), RAM (random access memory) for temporarily storing image data and other operational data
y) (S-RAM).

The main controller 90 is connected to the ADF 9, scanner 4, printer 6, operation panel 91, image processor 92, page memory 93, HDD 94, and heater drive circuit 97 via a bus 95. . The image processing unit 92, page memory 93, and HDD 94 are connected to the image bus 9
6 are connected.

The operation panel 91 is provided on the front upper portion of the apparatus main body 2 and instructs various copying conditions such as a copy magnification and the start of copying.

The image processing section 92 processes an original image read by the scanner section 4 and performs processing on the page memory 93 and the HD.
D94, and processes the processed image data in the page memory 93, the printer unit 6, or the HD.
D94.

The image processing section 92 has a compression / expansion circuit (not shown).
The image data from the HDD 94 is compressed, and the image data from the HDD 94 is decompressed.

The page memory 93 registers image data from the image processing section 92.

The HDD 94 is an external storage device represented by a hard disk for storing various data. For example, when copying a plurality of copies, an image obtained by compressing read images of a plurality of document images is registered, and the compressed image is read and printed at the time of printing.

The heater drive circuit 97 supplies a power supply voltage to the dew condensation preventing heaters 81 and 82 and the moisturizing heater 83 based on a control signal from the main control unit 90.

The main control section 90 has an input task and a print task managed for each job.

The main controller 90 includes an induction heating device (I
H) 58a is connected. The supply or cutoff of the power supply voltage to the induction heating device (IH) 58 a provided in the fixing device 58 of the printer unit 6 is controlled by the main control unit 90.
Is controlled by a control signal to the drive circuit 84.

Next, in the above configuration, when the power is turned on and off, and when the sleep mode is set, the heaters 81 and 82 for preventing dew condensation and the heater 83 for keeping moisture are turned on as dump heaters.
The off process will be described with reference to the flowchart shown in FIG.

First, when a power switch (not shown) is turned off (ST1), the main control unit 90 controls the heater drive circuit 97
Is output (ST2). As a result, the power supply voltage is supplied to the heaters 81 and 82 for preventing dew condensation and the heater 83 for keeping moisture by the heater driving circuit 97,
It is turned on and returns to step 1.

When the power switch is turned on in step 1, the main controller 90 outputs an off signal to the heater drive circuit 97 (ST3). As a result, the supply of the power supply voltage to the heaters 81 and 82 for preventing dew condensation and the heater 83 for keeping moisture by the heater driving circuit 97 is cut off, so that the heater driving circuit 97 is turned off.

At this time, after performing the initial operation process (warming up), the main control unit 90 outputs an ON signal to the drive circuit 84 (ST4). Thus, the power supply voltage is supplied to the induction heating device (IH) 58a by the drive circuit 84, so that the device is turned on.

Thereafter, when the fixing temperature reaches a predetermined temperature, the main control section 90 enters a ready state (ST5). In this state, the main control unit 90 performs copy processing based on various settings from the operation panel 91 (ST6, ST7).
After the end of the copy processing, the process returns to the ready state of step 5 again.

In the ready state of step 5, when the setting from the operation panel 91 has not been performed for a predetermined time or more, the main control unit 90 determines the sleep mode (ST).
6) Output an ON signal to the heater drive circuit 97 (ST)
8). As a result, power is supplied to the heaters 81 and 82 for preventing dew condensation and the heater 83 for moisturizing by the heater drive circuit 97, so that the heaters are turned on.

At this time, the main controller 90 controls the driving circuit 8
Then, an off-signal is output to ST4 (ST9). As a result, the supply of the power supply voltage to the induction heating device (IH) 58a by the drive circuit 84 is cut off, so that the device is turned off.

Thereafter, when a setting is made from the operation panel 91, the main control unit 90 determines the release of the sleep mode (ST10), and outputs an off signal to the heater drive circuit 97 (ST11). Thus, the heaters 81 and 82 for preventing dew condensation and the heater 83 for moisturizing by the heater driving circuit 97 are provided.
It is turned off by shutting off the supply of the power supply voltage to the power supply.

At this time, the main controller 90 controls the driving circuit 8
Then, an on-signal is output to No. 4 (ST12). Thus, the power supply voltage is supplied to the induction heating device (IH) 58a by the drive circuit 84, so that the device is turned on.

Thereafter, when the fixing temperature reaches a predetermined temperature, the main control unit 90 enters the ready state of step 5 described above.

Next, on / off processing of the dew condensation preventing heaters 81 and 82 and the moisturizing heater 83 based on the standard power consumption of the equipment will be described with reference to the flowcharts shown in FIGS. I do.

First, when the power switch (not shown) is off (ST21), the main control unit 90 sets the heater drive circuit 9
Then, an ON signal is outputted to ST7 (ST22). Thus, the heaters 81 and 8 for preventing dew condensation are generated by the heater driving circuit 97.
2. When the power supply voltage is supplied to the moisturizing heater 83, the heater 83 is turned on, and the process returns to step S21.

If the power switch is turned on in step 21, the main control section 90 performs an initial operation process (warming up) (ST23), and then outputs an ON signal to the drive circuit 84 (ST24). Thus, the power supply voltage is supplied to the induction heating device (IH) 58a by the drive circuit 84, so that the device is turned on.

After that, the main control unit 90 controls the induction heating device (I
H) When the power supplied to 58a becomes 1200 W or more (ST25), it is determined that the limit value of the total power consumption of the device is reached (exceeds the standard value), and an off signal is sent to the heater drive circuit 97. Output (ST26). Thus, the heater 8 for preventing dew condensation by the heater drive circuit 97 is provided.
1, 82, the supply of the power supply voltage to the moisturizing heater 83 is cut off, so that the heater 83 is turned off.

In step 25, the power supply becomes 120
When the fixing temperature reaches a predetermined temperature without being equal to or higher than 0 W, or when the heater 81 to 8
When the fixing temperature reaches the predetermined temperature after the turning off of Step 3, the main control unit 90 enters a ready state (ST27).

In this state, in order to maintain the temperature of the fixing device 58 at a predetermined temperature, the main control unit 90 changes the power supply to the induction heating device (IH) 58a (ST2).
8) The power supplied to the induction heating device (IH) 58a is 12
When the power becomes 00 W or more (ST29), the heaters 81 to 8
3 is turned on or off (ST30), and when turned on, an off signal is output to the heater drive circuit 97 (ST31). As a result, the supply of the power supply voltage to the heaters 81 and 82 for preventing dew condensation and the heater 83 for keeping moisture by the heater driving circuit 97 is cut off, so that the heater driving circuit 97 is turned off.

Further, the main controller 90 controls the induction heating device (I
H) When the power supply to 58a is changed (ST2)
8) The power supplied to the induction heating device (IH) 58a is 12
When the power is less than 00 W (ST29), the heaters 81 to 8
3 is turned on or off (ST32), and when turned off, an on signal is output to the heater drive circuit 97 (ST33). As a result, the heater drive circuit 97 supplies power to the dew condensation preventing heaters 81 and 82 and the moisturizing heater 83 to be turned on.

If the heaters 81 to 83 are turned off in step 30, the heaters 81 to 83 are turned off in step 31, and then the heaters 81 to 83 are turned off in step 32.
Is ON, the heaters 81 to 83 are set in step 33.
Is turned on, a copy process is performed based on various settings from the operation panel 91 (ST34).

In this state, in order to maintain the temperature of the fixing device 58 at a predetermined temperature, the main control portion 90 changes the power supply to the induction heating device (IH) 58a (ST3).
5) The power supplied to the induction heating device (IH) 58a is 12
When the power becomes 00 W or more (ST36), the heaters 81 to 8
3 is turned on or off (ST37), and when turned on, an off signal is output to the heater drive circuit 97 (ST38). As a result, the supply of the power supply voltage to the heaters 81 and 82 for preventing dew condensation and the heater 83 for keeping moisture by the heater drive circuit 97 is cut off, so that the heaters are turned off.

Further, the main controller 90 controls the induction heating device (I
H) When the power supply to 58a is changed (ST3
5) The power supplied to the induction heating device (IH) 58a is 12
When the power becomes 00 W or less (ST36), the heaters 81 to 8
3 is turned on or off (ST39), and when turned off, an off signal is output to the heater drive circuit 97 (ST40). As a result, the heater drive circuit 97 supplies power to the dew condensation preventing heaters 81 and 82 and the moisturizing heater 83 to be turned on.

If the heaters 81 to 83 are turned off in step 37, the heaters 81 to 83 are turned off in step 38, and then the heaters 81 to 83 are turned off in step 39.
Is on, the heaters 81 to 83
Is turned on and the copy processing is completed (ST4
1) Return to the ready state of step 27 again.

As described above, in the sleep mode, the heater for preventing dew condensation and the heater for keeping the paper moist are turned on. When the amount of power supplied to the induction heating device is equal to or more than a predetermined amount of power, the dew condensation is prevented. Turn off the heater for heating the paper and the heater for keeping the paper moist, and turn on the heater for preventing dew condensation and the heater for keeping the paper moist when the amount of power supplied to the induction heating device is equal to or less than the predetermined power amount. is there.

When the power supply to the fixing device is cut off when the power is turned off or the operation of the apparatus is not performed for a predetermined time, the heater for preventing dew condensation and the heater for keeping the paper moist are turned on. Further, it is possible to control on / off of a heater for preventing dew condensation and a heater for moisturizing paper based on the amount of electric power supplied to the induction heating device.

That is, it is possible to turn on only the heater for preventing dew condensation and the heater for keeping the paper moist.

[0070]

As described above in detail, according to the present invention, when the power supply to the fixing device is cut off when the power is turned off or when the operation of the device is not performed for a predetermined time, the dew condensation is prevented. Heaters and paper heaters can be turned on, and based on the total power consumption of the equipment,
It is possible to provide an image forming apparatus capable of controlling on and off of a heater for preventing dew condensation and a heater for keeping paper moist.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a digital copying machine for explaining an embodiment of the present invention.

FIG. 2 is a block diagram showing an internal configuration of a control circuit of the digital copying machine.

FIG. 3 is a flowchart for explaining on / off processing of the dump heater when the power is turned on / off and in the sleep mode.

FIG. 4 is a flowchart for explaining on / off processing of a dump heater based on the standard power consumption of a device.

FIG. 5 is a flowchart for explaining on / off processing of a dump heater based on the standard power consumption of the device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Digital copying machine, 2 ... Apparatus main body, 4 ... Scanner part,
6 printer unit, 58 fixing device, 58a induction heating device, 58b heating roller, 58c pressure roller, 81
82: a heater for preventing dew condensation, 83: a heater for keeping moisture, 8
4 drive circuit, 90 main control unit, 91 operation panel, 9
2. Image processing unit, 97: heater drive circuit.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H027 DA01 DA38 EA18 EC20 ED01 ED08 ED25 ED30 EE02 EE07 EE08 EF01 EF04 EF09 EF13 EF17 JA12 JA16 JB19 JC01 JC06 JC08 JC12 2H033 AA32 AA39 CA18 CA21 CB02 DA02

Claims (6)

[Claims] 1. An image forming apparatus having a heater for preventing dew condensation and forming an image on an image forming medium based on various settings from an operation panel, controls on / off of the heater for preventing dew condensation. Control means, a first processing means for turning on a heater for preventing dew condensation by the control means when the power is turned off, and turning off a heater for dew condensation prevention by the control means when the power is turned on; The second processing means for turning on the dew condensation prevention heater by the control means when the setting of the control means has not been performed for a predetermined time or more, and the second processing means for turning on the dew condensation prevention heater by the control means. An image forming apparatus comprising: a third processing unit that turns off a heater for preventing dew condensation by the control unit when a setting is made from an operation panel. 2. An image forming apparatus having a heater for preventing dew condensation and forming an image on an image forming medium, wherein the dew condensation prevention is performed according to whether the total power consumption of the apparatus is equal to or less than a predetermined power amount. An image forming apparatus comprising: a control unit that controls on / off of a heater for use in the image forming apparatus. 3. An image forming apparatus for forming an image on an image forming medium, comprising a fixing device for fixing a developer image on the image forming medium by induction heating a heating roller and a heater for preventing dew condensation. An image forming apparatus comprising: a control unit that controls on / off of the condensation prevention heater according to whether the power consumption of the fixing device is equal to or less than a predetermined power amount. 4. An image forming apparatus having a heater for moisturizing an image forming medium and forming an image on the image forming medium based on various settings from an operation panel. Control means for controlling turning off; first processing means for turning on the moisturizing heater by the control means when the power is off; turning off the moisturizing heater by the control means when the power is on; A second processing unit that turns on the moisture-holding heater by the control unit when the setting from the panel is not performed for a predetermined time or more; and a second process unit that turns on the moisture-holding heater by the control unit. An image forming apparatus comprising: a third processing unit that turns off a moisture retention heater by the control unit when a setting is made from an operation panel. 5. An image forming apparatus having a heater for moisturizing an image forming medium and forming an image on the image forming medium, wherein the total power consumption of the apparatus is equal to or less than a predetermined amount of power. An image forming apparatus comprising: a control unit that controls on / off of the moisturizing heater. 6. A fixing device for inductively heating a heating roller to fix a developer image on an image forming medium, and a heater for moisturizing the image forming medium, and forming an image on the image forming medium. An image forming apparatus, comprising: a control unit that controls on / off of the moisturizing heater according to whether the power consumption of the fixing device is equal to or less than a predetermined amount of power.