JPH10207326A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the optimum rotating time of a cooling fan to be set and to effectively cool the inside of a device by controlling the driving of the fan cooling the inside of a device main body according to a mode. SOLUTION: When printing work is started, a photoreceptor drum 1 is rotated but the cooling fan 18 is not rotated while a latent image is formed. Then, the rotation of the fan 18 is started by a fan control means 17b just before a recording sheet rushes in a nip between a fixing roller 13 and a pressure roller 14. While the recording sheet is ejected to an ejection tray 16 through a carrying path, it is exposed to external air immediately after it is heated by the fixing nip N so as to be cooled. Besides, when the recording sheet is positioned between the nip N and the tray 16, the external air is not advanced toward the inside of the device main body and it is discharged to the outside of the device main body by a louver 19 after the recording sheet is cooled. The rotation of the fan 18 is stopped prescribed time after the printing work is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus to which an electrophotographic method is applied, such as a copying machine and a printer, and more particularly to an image forming apparatus having a cooling fan.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a conventional image forming apparatus.
The image forming apparatus 50 includes a laser 52 on the charged photosensitive drum 51.
Is radiated through the polygon mirror 53 to form an electrostatic latent image, which is visualized by colored charged particles (hereinafter referred to as toner). Then, the recording sheet fed from the cassette 54 by the sheet feeding roller 55 is guided to the nip between the photosensitive drum 51 and the transfer roller 56 to transfer the toner, and the recording sheet is further fixed to a fixing roller 58 which is a heat fixing device. It is inserted into the nip of the pressure roller 60, and is heated and pressed to fix. The toner remaining on the photosensitive drum 51 is wiped by the cleaner 57.

The heater 59 disposed in the fixing roller 58 is maintained at a constant temperature range, but the temperature range needs to be as high as 130 ° C. to 200 ° C. depending on the melting point of the toner. Electric power is also 300W according to the peripheral speed of the photosensitive drum
It is generally up to 1500W.

The heat generated by the heater 59 is mainly used for fixing the toner. However, a part of the heat generated by the heater 59 includes the fixing roller 58, the pressure roller 60, and other parts of the image forming apparatus 50 and the internal air (hereinafter referred to as internal temperature rise). Temperature). For example, if the temperature of the cleaner 57, which is often located in the vicinity of the fixing roller 58, exceeds the softening point of the toner (about 50 to 60 ° C.), it causes toner clogging, and waste toner is not collected in the cleaner. This will cause serious problems such as toner spilling inside the machine, resulting in image contamination.

Therefore, an exhaust cooling fan 62 is provided in the vicinity of the fixing roller in order to discharge extra heat inside the apparatus outside the apparatus. At this time, the cooling efficiency can be increased by providing the louvers 63 and taking in relatively cool air outside the apparatus.

By providing a cooling fan 61 separately and taking in air outside the machine into the machine, an airflow can be created inside the machine as shown in FIG. Thereby, each member heated in the machine can be efficiently cooled by the relatively cool outside air. In the case of a cooling fan that draws in air outside the device, a filter 64 is provided because dust inside the device may stain the components inside the device or cause functional deterioration.

As a method of controlling the cooling fans 61 and 62, for example, rotation is started at the start of printing and cooling is performed, and rotation is maintained for a predetermined time (for example, 30 seconds) from the end of printing to maintain cooling. And then stop. This does not change whether the printing instruction is continuous printing or intermittent printing.

[0008] Alternatively, the device is driven for a predetermined time during printing and after printing as described above, and a thermistor is provided on the substrate to constantly detect the temperature on the substrate. C.), the cooling fan may be turned on for a predetermined time (for example, 30 seconds).
In this method, the temperature of the thermistor is detected again at every predetermined time, and if the temperature exceeds the predetermined temperature at that time, the control of turning the cooling fan for another predetermined time is repeated.

As another example of the control method, the cooling fans 61 and 62 are always rotated at half speed while the main power of the image forming apparatus is turned on, and are rotated at full speed when printing is started.
Then, the rotation at full speed is maintained for a predetermined time (for example, 30 seconds) after printing is completed, and if the next printing is not started within the predetermined time, the rotation speed is reduced to half speed.

When an image is formed on both sides by reversing the recording sheet, the temperature of the recording sheet on which the image is fixed passes through the main body again, so that the temperature inside the apparatus increases more sharply. Therefore, a cooling time is set even when images are formed on both sides, and the cooling fan 6 is set after printing is completed.
The rotation of 1,62 is maintained.

[0011]

In the control method as described in the above conventional example, the rotation maintaining time of the cooling fan after printing is set on the assumption that the temperature inside the image forming apparatus becomes the highest. I have. That is, the internal temperature after printing, the size of the recording sheet, double-sided printing or single-sided printing,
The rotation of the cooling fan is controlled irrespective of printing conditions such as continuous printing or intermittent printing.

For example, in the case of intermittent printing, although the degree of temperature rise is lower than in continuous printing, the rotation time of the cooling fan after printing is set so that cooling is possible even in continuous printing. Similarly, in an image forming apparatus capable of performing both double-sided printing and single-sided printing, the rotation time of the cooling fan is set so that cooling can be performed even in the case of double-sided printing at a higher temperature.

Therefore, when the number of printed sheets is small, when intermittent printing is performed, when single-sided printing is performed, the cooling fan is turned excessively even though the temperature inside the apparatus is not so high.

However, when the cooling fan is rotated more than necessary, there is a problem that the operation sound of the image forming apparatus is generated for a long time. In addition, since a cooling fan having a long guaranteed rotation time must be used, the production cost increases.

Further, since the outside air is taken into the image forming apparatus, dust contained in the outside air adheres to the inside of the apparatus and causes dirt, and adheres to optical members such as the laser 52 and the polygon mirror 53 and causes a deterioration in function. Also. For this reason, a filter is attached to the opening of the cooling fan, but the filter is clogged by long-term use, so that the filter must be constantly replaced.

An object of the invention according to the present application is to shorten the rotation time of a cooling fan in an image forming apparatus having a cooling fan of an intake system while efficiently suppressing the temperature rise in the apparatus.

[0017]

According to an aspect of the present invention, there is provided an image forming apparatus for recording an image on a recording medium in accordance with a print mode by fixing an image recorded on the recording medium. A heat fixing device for causing
A fan for cooling the inside of the apparatus main body and fan control means for controlling the drive of the fan are configured to control the drive of the fan according to the print mode.

This makes it possible to set an optimum cooling fan rotation time in response to the fact that the internal temperature rise differs depending on the printing mode in the image forming state, and to shorten the cooling fan rotation time as much as possible. Therefore, the inside of the image forming apparatus can be effectively cooled, and the influence of dust on the optical system member can be minimized.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] A first embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of the image forming apparatus according to the present embodiment, and FIG. 2 is an enlarged view of a fixing nip. First, a schematic configuration of the apparatus main body A of the image forming apparatus shown in FIG. 1 will be described, and a procedure for performing a printing operation will be briefly described.

When an instruction to start printing is sent from the host computer (not shown) to the main body control means 17, the photosensitive drum 1 rotates in the direction of the arrow according to the designated print mode, and the surface thereof is made uniform by the charging roller 2. It is charged to a potential. While scanning the photosensitive drum 1 with the output light of the laser 3 by the polygon mirror 4 in the longitudinal direction of the photosensitive drum 1,
The exposure 5 is emitted by turning on and off the output of the laser 3 according to the image information. Then, the portion irradiated with the light is neutralized to form an electrostatic latent image, which is supplied with colored charged particles (hereinafter referred to as toner 7) by the developing device 6 to be visualized.

In the cassette 8, recording sheets, which are recording media, are stacked and held. The recording sheets are taken out one by one by a feeding roller 9, and are synchronized with a visible image on the photosensitive drum 1 by a registration roller 10 to be exposed. It is inserted through a nip formed between the drum 1 and the transfer roller 11. In FIG. 1, the path through which the recording sheet passes is indicated by a solid line.

The transfer roller 11 applies a charge having a polarity opposite to that of the toner 7 to the back surface of the recording sheet, so that the toner 7 is electrostatically transferred to the recording sheet. The transfer residual toner on the photosensitive drum 1 is wiped by the cleaner 12, and the photosensitive drum 1 is used in the next image forming process.

The recording sheet onto which the toner 7 has been transferred includes a fixing roller 13 as a fixing member and a pressure roller as a pressing member.
The toner 7 is permanently fixed to the recording sheet by being inserted into the fixing nip N of the heat fixing device composed of the recording sheet 14 and heated and pressed. Thereafter, the recording sheet is conveyed and discharged onto the discharge tray 16. The fixing roller 13 has a heater 15 for heating.
Is built-in.

The fixing roller 13 is a tensionless type film heating and fixing device. As shown in FIG. 2, the fixing roller 13 has a thin heat-resistant film 13a, which is a rotatable cylindrical member, attached to a support 13b. It is fitted. The inner peripheral length of the heat-resistant film 13a and the outer peripheral length of the support 13b are slightly larger (for example, about 3 mm) in the heat-resistant film 13a, so that the heat-resistant film 13a has a peripheral length relative to the support 13b. Is loosely fitted. The heat-resistant film 13a has a small heat capacity to improve quick start,
Film thickness is 100 μm or less, preferably 50 μm or less
It is formed of a heat-resistant material of μm or more.

The pressure roller 14 forms a fixing nip N with the heat-resistant film 13a sandwiched between the pressure roller 14 and the heater 15, presses the recording sheet against the heat-resistant film 13a, and applies a conveying force to the recording sheet. Is provided. The pressure roller 14 has a core metal 14a integrally provided with a heat-resistant rubber roller portion 14b of silicon rubber or the like having good releasability, and transmits a driving force to a gear (not shown) attached to an end of the core metal 14a. It rotates by driving.

A heater 15 for heating the heat-resistant film 13a is attached to the support 13b.
The output of the 13 surface temperature sensors 15a is output to the temperature controller 17a.
And the power supply to the heater 15 is turned on and off to maintain the temperature within a certain temperature range. Thereby, the recording sheet passing through the fixing nip N is heated, and the toner image transferred by the image forming unit is permanently fixed on the recording sheet.

A cooling fan 18 of an air intake system is provided near the fixing roller 13 of the apparatus main body A, and is configured to take in relatively cool air outside the apparatus into the apparatus. The rotation of the cooling fan 18 is controlled by fan control means 17b.

A louver 19, which is a vent, is provided on the other surface of the apparatus main body A. That is, the outside air sucked from the cooling fan 18 cools the heated member inside the machine,
Exhausted from the louver 19 outside the aircraft. In the case of the cooling fan 18 that draws in air outside the device, the filter 20 is provided because dust inside the device may stain components inside the device or cause functional deterioration.

The recording sheet that has passed through the fixing nip N is guided to a discharge tray 16 by a transport path P indicated by a solid line in FIG. A discharge sensor 16a is provided near the discharge tray 16.
Is provided, and detects that the recording sheet has passed, and sends a signal to the main body control means 17. The printing operation on one recording sheet is completed as described above.

Next, control of the cooling fan 18 by the fan control means 17b will be described. When the printing operation is started, the cooling fan 18 is not rotated while the photosensitive drum 1 is rotating to form a latent image, and the recording sheet is
Immediately before the roller 13 and the pressure roller 14 enter the nip, the fan control means 17b starts the rotation. Thus, noise during printing can be reduced, and dust reaching the photosensitive drum 1 can be reduced.

Thus, while the recording sheet is discharged to the discharge tray 16 along the transport path P indicated by the solid line arrow, the cooling fan 18 cools the recording sheet by applying outside air immediately after the recording sheet is heated by the fixing nip. Even during continuous printing, the toner on the recording sheets stacked on the discharge tray 16 can be prevented from peeling.

When the recording sheet is located between the fixing nip N and the discharge tray 16, the outside air does not go to the inside of the apparatus main body A. It is exhausted outside. At the time of continuous printing, the recording sheet is continuously conveyed, so that even if the outside air contains dust, it does not diffuse into the apparatus main body A.

When the printing instruction from the host computer is interrupted, the apparatus main body A shifts to a standby state. At this time, the rotation of the cooling fan 18 is stopped after a lapse of a predetermined time after printing is completed. The predetermined time is determined in accordance with a temperature control mode at the time of printing completion, which will be described below, among the print modes by the main body control unit 17.

The temperature control mode is a temperature setting (hereinafter referred to as a fixing temperature) for fixing the toner 7 on the recording sheet in the heater 15 of the fixing roller 13 and is determined by the number of prints and the temperature condition. Hereinafter, a temperature control mode control sequence of the apparatus main body A according to the present embodiment will be described. Table 1 shows the relationship between the number of prints and the temperature control temperature when the pressure roller is close to room temperature (when power is turned on, etc.).

[0035]

[Table 1]

Next, the temperature condition and the temperature control mode will be described. Table 2 shows the relationship between the initial temperature detected by the surface temperature sensor 15a and the temperature control mode entered at that time.

[0037]

[Table 2]

That is, according to Tables 1 and 2, for example, when the temperature of the fixing roller 13 at the start of printing is 25 ° C., printing is started from the first temperature control and the heating from the first sheet to the tenth sheet is performed. The fixing temperature of the heater 15 is 210 ° C., the second temperature control is performed from the 11th sheet to the 20th sheet, and the fixing temperature is 200 ° C., and similarly, the third temperature control, the fourth temperature control and the fixing temperature are controlled. . For example, when the initial temperature is 60 ° C, printing starts from the third temperature control, and printing starts from the first sheet.
The fixing temperature is 190 ° C for the 10th sheet, the fourth temperature control is applied to the 11th to 20th sheets, and the fixing temperature is 180 ° C. From the 21st sheet, the fixing temperature is 170 ° C. I do.

In the apparatus main assembly A having the above-described fixing temperature control sequence, when the temperature control mode at the end of printing is the first temperature control or the second temperature control, the printing time is short and the temperature rise in the apparatus is not so large. Therefore, immediately after the printing is completed, the rotation of the cooling fan 18 is stopped. If the temperature control mode at the end of printing is the third temperature control or the fourth temperature control, the cooling fan 18 is turned off for 10 seconds after printing is completed, and then turned off. If the temperature control mode at the end of printing is the fifth temperature control, the cooling fan 18 is turned on for 30 seconds after printing is completed, and then the rotation is stopped.

As described above, the time during which the cooling fan 18 is turned on after printing is not fixed, but is optimized in accordance with the temperature control mode at the time of printing, so that the temperature of the recording sheet or the inside of the machine during printing can be increased. It can be prevented efficiently. Therefore, it is possible to prevent the device main body A from being stained with dust and the function from deteriorating by inhaling outside air more than necessary. Particularly, in many cases, the number of prints in one job is about two to three on average, so if the rotation of the cooling fan 18 is stopped immediately after printing is completed, the rotation time of the cooling fan 18 can be extremely reduced. .

[Second Embodiment] In this embodiment, in addition to the control of the cooling fan 18 in accordance with the temperature control mode shown in the first embodiment, the size of the recording sheet is detected, and the cooling after printing is completed by both of them. This determines the time during which the fan 18 is running. The image forming apparatus is the same as that of the first embodiment, and the description is omitted.

When the width of the recording sheet is smaller than the maximum width that can be conveyed by the image forming apparatus, a portion where the recording sheet does not pass in the longitudinal direction of the fixing roller 13 (hereinafter, referred to as a non-passing portion) occurs. However, the heater 15 for heating is
Therefore, when the area of the non-passing portion increases, the heat of the heating heater 15 accumulates in the fixing roller 13 and the temperature inside the apparatus increases sharply.

Therefore, a predetermined size (for example, a size having a width of B5) is set, and a case where the recording sheet is smaller than the predetermined size is regarded as a small size sheet, and a case where the recording sheet is larger than the predetermined size (for example, A4, LTR, Legal, etc.). ) Is a normal size sheet. When the recording sheet is a small size sheet, the time during which the cooling fan 18 is turned after printing is longer than when the recording sheet is a normal size sheet. Table 3 shows the relationship between the temperature control mode at the end of printing, the sheet size, and the time during which the cooling fan 18 is rotated after the end of printing.

[0044]

[Table 3]

According to Table 3 above, for example, when the temperature control mode is the first temperature control or the second temperature control and a normal size sheet is set, the rotation of the cooling fan 18 is ended simultaneously with the end of printing. . However, similarly, even if the temperature control mode is the first temperature control or the second temperature control, if the sheet is a small size sheet, the rotation of the cooling fan 18 is maintained for 10 seconds after printing is completed. Even in other temperature control modes, if the recording sheet is a small size sheet, the time for maintaining the rotation is set to be long (double in the above example).

As described above, by optimizing the time for keeping the rotation of the cooling fan 18 after the printing is completed in accordance with the temperature control mode at the time of printing and the size of the recording sheet, the temperature rise of the recording sheet or the inside of the machine at the time of printing is achieved. Can be efficiently prevented. This prevents the apparatus main body A from being stained with dust and deteriorating its function, and prevents the non-passing portion of the fixing roller from excessively heating even when printing is performed on a small-sized sheet.

[Third Embodiment] In the present embodiment, in addition to the control of the cooling fan 18 according to the temperature control mode performed in the first embodiment, the rotation of the cooling fan 18 depends on the continuous printing mode or the intermittent printing mode. The control is performed. The image forming apparatus is the same as that of the first embodiment, and the description is omitted. Here, continuous printing means that the previous recording sheet is a discharge sensor
When the next print signal is received when the sheet passes through the sheet 16a, the intermittent printing is when the next print signal is received within 60 seconds after the previous recording sheet has passed the discharge sensor 16a.

When the intermittent printing is performed, since the heating heater 15 is turned off for a long time, the temperature in the apparatus main body A does not rise so much as compared with the case of the continuous printing. Therefore, in the case of intermittent printing, the cooling fan 18
The time of turning is short. Table 5 shows the relationship between the temperature control mode at the end of printing, whether continuous printing or intermittent printing is performed, and the time during which the cooling fan 18 is turned on after printing is completed.

[0049]

[Table 4]

According to Table 4, for example, when the temperature control mode is the first temperature control or the second temperature control and intermittent printing is performed, the rotation of the cooling fan 18 is ended simultaneously with the end of printing. However, similarly, even when the temperature control mode is the first temperature control or the second temperature control, if continuous printing is performed, the rotation of the cooling fan 18 is maintained for 10 seconds after printing is completed. Even in other temperature control modes, the time for maintaining the rotation of the cooling fan 18 is set to be longer (in the above example, twice as long) in the case of continuous printing than in the case of intermittent printing. .

As described above, by optimizing the temperature control mode at the end of printing and the time for maintaining the rotation of the cooling fan 18 in accordance with the continuous printing or the intermittent printing, the rotating time of the cooling fan 18 can be minimized. Can be suppressed. Accordingly, it is possible to efficiently cool the temperature of the recording sheet during printing and the inside of the apparatus, and also to prevent dust from adhering to the inside of the apparatus main body A and soiling or functional deterioration.

[Fourth Embodiment] In this embodiment, in addition to the control of the cooling fan 18 according to the temperature control mode shown in the first embodiment, the rotation of the cooling fan 18 depends on whether it is a single-sided printing mode or a double-sided printing mode. The control is performed. FIG. 3 is a longitudinal sectional view of an image forming apparatus having the automatic duplex unit according to the present embodiment.

FIG. 3 shows an apparatus body A with an automatic duplex unit B
FIG. 3 shows a vertical cross-sectional view in the case where is attached. In the apparatus main body A, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description is omitted. In other words, the apparatus main body A itself functions as a single-sided printing apparatus. However, by combining the automatic double-sided unit B with this, the recording sheet on which single-sided printing has been completed is turned over, re-fed to the apparatus main body A, and sent to the back side. Printing is automatically performed.

A flapper 21 is provided in the apparatus main body A, and moves to a position shown by a broken line in the figure when printing on one side and when printing the second side of double-sided printing, and shows a recording sheet by a broken line. It operates to guide to the discharge tray 16 on the transport path.
When printing the first side of the double-sided printing, the printing sheet is moved to the position indicated by the solid line in the figure, and the recording sheet is guided to the automatic double-sided unit B along the transport path indicated by the solid line.

After the printing on one side is completed, the automatic duplex unit B
The recording sheet guided to is rotated in the reverse direction by the reversing roller 22 and is again fed to the apparatus main body A by the re-feed roller 24. At this time, the recording sheet is guided from the vicinity of the cassette 8 to the transport path, and undergoes a process similar to that for single-sided printing to complete double-sided printing.

It should be noted that, without switching between the leading and trailing ends of the recording sheet in the automatic double-sided unit B without passing through the reversing roller 22,
Multiple printing, in which the same second surface as the first surface is printed by a known method, can also be executed.

A cooling fan 23 of an exhaust system is provided on the side of the automatic double-sided unit B, and the recording sheet immediately after being discharged from the fixing nip and the gas such as water vapor generated therefrom are exhausted outside the apparatus. This prevents the temperature inside the apparatus main body A from becoming too high due to the heat accumulated in the recording sheet during the fixing process.

When double-sided printing is performed, the high-temperature recording sheet once fixed passes through the inside of the apparatus main body A again, so that the temperature inside the apparatus main body A increases more than in the case of single-sided printing. Therefore, in the case of double-sided printing, it is necessary to make the time for rotating the cooling fan 18 after printing to be longer than in the case of single-sided printing. Table 5 shows the temperature control mode at the end of printing, whether the printing is double-sided printing or single-sided printing, and the cooling fan 18 after printing is completed.
It shows the relationship of the time of turning 23.

[0059]

[Table 5]

According to Table 5, for example, when the temperature control mode is the first temperature control or the second temperature control and the printing is one-sided printing, the rotation of the cooling fans 18 and 23 is terminated at the same time as the printing is completed. Let it. However, similarly, even when the temperature control mode is the first temperature control or the second temperature control, in the case of double-sided printing,
The rotation of the cooling fans 18 and 23 is maintained for 10 seconds after printing is completed.
Even in other temperature control modes, the time to maintain the rotation of the cooling fans 18 and 23 is set longer (double the length in the above example) for duplex printing than for single-sided printing. ing.

By optimizing the time for maintaining the rotation of the cooling fans 18 and 23 after the end of printing in accordance with the temperature control mode at the end of printing and whether one-sided printing or two-sided printing is performed,
The rotation time of the cooling fans 18 and 23 can be minimized. Accordingly, it is possible to efficiently cool the temperature of the recording sheet during printing and the inside of the apparatus, and also to prevent dust from adhering to the inside of the apparatus main body A and soiling or functional deterioration.

In the above embodiment, the temperature control mode,
Temperature control mode and recording sheet size, temperature control mode and intermittent /
The example in which the cooling fan 18 is controlled according to the continuous printing, the temperature control mode, and the single-sided / double-sided printing has been described. However, the present invention is not limited to this. For example, the rotation of the cooling fan is controlled according to the temperature control mode and the size of the recording sheet, intermittent / continuous printing, and single-sided / double-sided printing according to the capability of the image recording apparatus. It may be controlled.

[0063]

As described above, according to the present invention,
By changing the time during which the cooling fan of the intake system is rotated according to each printing mode such as the temperature control mode at the end of printing, it is possible to efficiently suppress the temperature rise in the apparatus and cool the recording sheet. . In addition, since airflow flowing through the image forming apparatus is minimized, dirt inside the apparatus,
In particular, dirt on optical system members such as photosensitive drums is reduced,
Functional deterioration can be suppressed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an image forming apparatus according to an embodiment.

FIG. 2 is an enlarged view of a fixing nip of the image forming apparatus according to the embodiment.

FIG. 3 is a longitudinal sectional view of the image forming apparatus having the automatic duplex unit according to the embodiment.

FIG. 4 is an example of a conventional image forming apparatus.

FIG. 5 is a schematic view of an airflow formed in an image forming apparatus of a conventional image forming apparatus.

[Explanation of symbols]

 A: apparatus body B: automatic duplex unit N: fixing nip P: transport path 1: photosensitive drum 2: charging roller 3: laser 4: polygon mirror 5: exposure 6: developing device 7: toner 8: cassette 9: feeding roller 10 ... Registration roller 11 ... Transfer roller 12 ... Cleaner 13 ... Fixing roller 13a ... Heat resistant film 13b ... Support 14 ... Pressurizing roller 14a ... Core metal 14b ... Heat resistant rubber roller part 15 ... Heating heater 15a ... Surface temperature sensor 16 ... Discharge tray 16a Discharge sensor 17 Main body control means 17a Temperature controller 17b Fan control means 18 Cooling fan 19 Louver 20 Filter 21 Flapper 22 Reverse roller 23 Exhaust cooling fan 24 Re-feed roller

Claims (9)

[Claims] 1. An image forming apparatus for recording an image on a recording medium according to a print mode, comprising: a heat fixing device for fixing an image recorded on the recording medium; a fan for cooling the inside of the apparatus main body; An image forming apparatus, comprising: fan control means for controlling driving of a fan; and controlling driving of the fan in accordance with the print mode. 2. The image forming apparatus according to claim 1, wherein the fixing device includes a heater for heating a recording medium via a film member, and a pressing member for pressing and conveying the recording medium. . 3. The printing mode includes a temperature control mode in which a heating temperature of the fixing device is changed, and the fan control unit controls driving of the cooling fan in accordance with the temperature control mode. The image forming apparatus according to claim 1. 4. The image according to claim 1, wherein the print mode includes a size of the detected recording medium, and the fan control unit controls the driving of the cooling fan according to the size of the recording medium. Forming equipment. 5. The apparatus according to claim 1, wherein the fan control unit controls the driving time of the cooling fan to be longer when the size of the recording medium is equal to or smaller than a predetermined size than when the size of the recording medium is the predetermined size. 5. The image forming apparatus according to 4. 6. The printing mode includes a continuous printing mode and an intermittent printing mode, wherein the fan control means controls the driving of the cooling fan according to the continuous printing mode and the intermittent printing mode. The image forming apparatus according to claim 1. 7. The image according to claim 6, wherein the fan control unit controls the driving time of the cooling fan to be longer when the printing mode is the continuous printing mode than when the printing mode is the intermittent printing mode. Forming equipment. 8. The printing mode includes a double-sided printing mode and a single-sided printing mode, wherein the fan control unit controls the driving of the cooling fan according to a case of the double-sided printing mode and a case of the single-sided printing mode. The image forming apparatus according to claim 1. 9. The image according to claim 8, wherein the fan control unit controls the driving time of the cooling fan to be longer when the printing mode is the double-sided printing mode than when the printing mode is the single-sided printing mode. Forming equipment.