JP2001242769A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-quality image forming device in which the noise by a fan for cooling a sheet material is suppressed and loading characteristics on a discharge tray are stabilized without causing a stain on the sheet material or defective loading such that the sheet materials tend to stick together on the discharge tray for the sheet material on which an image is formed. SOLUTION: The image forming device is equipped with a control part 60 which controls a heat-exhausting fan 30, a wind direction regulation plate 62 and a shutter 67 (ventilation conditions of a ventilation means) according to the state of the sheet material S loaded on a paper delivering tray 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus having a function of forming an image on a recording material such as a sheet, such as a copier, a printer, or a facsimile machine.

[0002]

2. Description of the Related Art Conventionally, as this type of image forming apparatus,
Those employing an electrophotographic recording method are widely used. This is done by developing a latent image formed on a photoconductor drum into a visible image, transferring this visible image (toner image) to a sheet material using electrostatic force, and then fixing the transferred image by heat. An image is recorded and formed on the sheet material.

Further, a double-sided image forming apparatus capable of recording and forming an image on the other side (back side) of a sheet material on which an image is formed on one side by the same operation as described above, and further, yellow, magenta and cyan A color image forming apparatus capable of recording and forming a full-color image by mixing toner such as black and black has also been proposed and implemented.

FIG. 5 shows a conventional example of an image forming apparatus using the electrophotographic method as described above. In this image forming apparatus, after a toner image formed on the photosensitive drum 151 is transferred to a sheet material by a transfer device 152, heat and pressure are applied to the sheet material by a fixing device 153, and the toner The image is fixed on the sheet material. After the fixing, the sheet material is sequentially discharged onto a tray 156 outside the apparatus by a discharge roller pair 155.

At this time, the sheet material is cooled by blowing air onto the image (toner image) surface of the sheet material by a heat-dissipating fan 154 that exhausts air from the inside of the apparatus. It prevented sticking to the back of the material.

[0006]

However, in the above-mentioned conventional image forming apparatus, since the sheet material immediately after the black and white image or the full-color image having a large amount of toner is heat-fixed has a high temperature, the cooling effect by the intake fan is obtained. Is not enough,
There is a possibility that the image surface and the non-image surface of the sheet material are stained on the tray, or the sheet materials tend to stick to each other, causing a stacking failure or being completely adhered.

Further, when the sheet is smooth, such as an OHP sheet or a sheet whose surface is smoothed in order to increase gloss, the tendency of sticking tends to increase.

Also, when the heat capacity of the sheet is smaller than the heat amount given by the fixing device, such as a thin sheet, sticking is likely to occur.

On the other hand, if the air flow of the fan is extremely increased in order to avoid such a cooling defect, the noise of the fan is directly increased by the fan because the exhaust port faces the outside of the apparatus directly. Problems such as discomfort had occurred.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to contaminate a sheet material on a discharge tray of a sheet material on which an image is formed, or to remove the sheet material. An object of the present invention is to provide a high-quality image forming apparatus which does not cause a stacking defect in which sheets tend to stick to each other, suppresses noise caused by a fan for cooling a sheet material, and stabilizes stackability on a discharge tray.

[0011]

In order to achieve the above object, according to the present invention, an image is formed by developing an electrostatic latent image formed on an image carrier with toner to form an image on a sheet material. Forming means, a sheet material loading section for loading the sheet material on which the image is formed by the image forming means, and exhausting air inside the apparatus to the outside of the apparatus, and applying wind to the sheet material loaded on the sheet material loading section. Control means for controlling a blowing condition of the blowing means in accordance with a state of the sheet material loaded on the sheet material stacking section, wherein the blowing means cools the sheet material by feeding the sheet material. It is characterized by having.

[0012] It is also preferable that the control means controls a blowing condition of the blowing means based on an amount of toner on a sheet material formed as an image by the image forming means.

[0013] Sheet material setting means capable of setting the thickness or material of the sheet material on which an image is formed is provided.
It is also preferable that the blowing condition of the blowing means is controlled based on the thickness or material of the sheet material set by the sheet material setting means.

There is provided sheet number setting means capable of setting the number of sheet materials on which images are formed, and the control means controls the blowing conditions of the blowing means based on the number of sheet materials set by the sheet number setting means. It is also suitable.

A temperature detecting means for detecting a temperature of the sheet material stacked on the sheet material stacking section, wherein the control means controls the air blowing means based on the temperature of the sheet material detected by the temperature detecting means; It is also preferable to control the air blowing conditions.

The apparatus further comprises size setting means for setting the size of a sheet material on which an image is formed, or size detecting means for detecting the size of the sheet material on which an image is formed.
Set by the size setting means or size detection means,
Alternatively, it is also preferable to control the blowing condition of the blowing unit based on the detected size of the sheet material.

The air blowing means includes a wind direction restricting portion having a first position for sending air to the entire area of the sheet material stacking section and a second position for sending air to a partial area of the sheet material stacking section. It is also preferable that the control means controls the blowing means so as to change the position of the wind direction regulating part based on the size of the sheet material set or detected by the size setting means or the size detecting means.

It is also preferable that the control means controls the blowing means so as to change a blowing amount for the sheet material stacked on the sheet material stacking section.

[0019] It is also preferable that the blowing means includes a plurality of fans, and the control means changes a number of fans to be operated among the plurality of fans to change a blowing amount to the sheet material.

The air blowing means includes a first air blowing path for sending air to the sheet material stacked on the sheet material stacking section, and a second air blowing path for exhausting air inside the apparatus to the outside of the apparatus. It is also preferable that the control means changes the air flow rate of the second air flow path to change the air flow rate for the sheet material.

[0021] It is also preferable that the blowing means includes an opening / closing means for opening and closing the second blowing path, and the control means controls the opening / closing means to change a blowing amount of the second blowing path. is there.

[0022]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The material, the shape, and the relative arrangement thereof should be appropriately changed depending on the configuration of the apparatus to which the invention is applied and various conditions, and are not intended to limit the scope of the invention to the following embodiments.

FIGS. 1 and 2 are schematic cross-sectional views showing the vicinity of a sheet discharging portion in a full-color copying machine as an image forming apparatus according to the present invention, FIG. 3 is a diagram showing a control method of the full-color copying machine, and FIG. It is a schematic sectional view of the whole machine.

Here, as the order of the description, first, the entire configuration of the full-color copying machine will be described with reference to FIG. 4, and then the configuration of the blowing means for cooling the sheet material after fixing in the sheet material discharging section will be described. 1 and FIG.

In FIG. 4, reference numeral 1 denotes a copying machine main body, on which an automatic document feeder 2 is supported so as to be openable and closable. The automatic document feeder 2 automatically feeds a document placed on a document placing table 2 a one by one onto a platen glass 3 of the copying machine main body 1 or a document set at a predetermined position on the platen glass 3. The platen glass 3 is brought into close contact with the platen glass 3.

Then, as described above, the platen glass 3
The image of the original set above is read by a reader unit 4 such as a CCD provided in the copying machine main body 1.

In the reader section 4, reference numeral 4a denotes a light source for irradiating the original with light, and 4b denotes a photoelectric conversion element such as a CCD for receiving reflected light from the original and converting it into an electric signal.
Are a mirror and a lens for guiding reflected light from the document to the photoelectric conversion element 4b.

The copier body 1 has an image forming section 5 as image forming means in which image forming stations 5M, 5Y, 5C and 5B corresponding to each color of magenta, yellow, cyan and black are arranged in a line. It has.

Each image forming station includes a photosensitive drum 6a to 6d as an image carrier for each color, and a charger 7a as a process means acting on the photosensitive drums 6a to 6d.
To 7d, developing units 8a to 8d, cleaning units 9a to 9d
Etc. are combined.

Below the image forming section 5, a belt transport section 10 having transfer units 10a to 10d for transferring the images (toner images) formed on the photosensitive drums 6a to 6d to the sheet material S is provided. Are arranged.

Further, on the upper side of the image forming section 5, there is provided a laser unit 11 as an image writing device for decomposing the image information read by the reader section 4 into respective color components and exposing them to the photosensitive drums 6a to 6d. Has been established.

Further, a sheet material S is provided at a lower portion of the copying machine main body 1.
Cassettes 12 and 13 for stacking and storing are stored so as to be able to be pulled out.

Further, a manual feeding section 14 is provided on the left side of the copying machine main body 1, and a large capacity feeding deck 15 is detachably mounted below the manual feeding section 14.

The feeding of the sheet material S is performed by setting the sheet size in advance (size setting means) or by prescanning the document and automatically selecting the size (size detection means). The sheet is appropriately fed out from the manual feed unit 14 or the feed deck 15 by the pickup roller 16, separated one by one by a pair of retard rollers 17, and stopped via a sheet feeding path including a plurality of pairs of conveying rollers 18. The skew is corrected by abutting against the pair of registration rollers 19.

The sheet material S is a pair of registration rollers 1
The image data is sent to the image forming section 5 at a timing according to 9.

The sheet material S sent to the image forming section 5 is conveyed by the belt conveying section 10 and is subjected to a known image forming process by a photosensitive drum 6 of each image forming station.
The images formed on a to 6d are successively superposed and transferred to form a multicolor image.

The sheet material S on which the multicolor image has been formed is sent to the fixing device 20 by the belt conveying section 10, and heat and pressure are applied to fix the transferred image.

The conveyance path of the sheet material S after the image is fixed is switched by the flapper 21, and when forming an image on only one side, the sheet material S is discharged by the discharge roller pair 22 onto the discharge tray 23 as a sheet material stacking unit outside the apparatus. When performing double-sided image formation, the sheet is guided to the reversing conveyance path 25 by the re-feed roller pair 24, is reversibly conveyed by the reversing conveyance roller pair 26, and is stored in the intermediate tray 27 as a storage unit with the image surface facing upward. .

Sheet materials S stacked on the intermediate tray 27
Is fed out by a pickup roller 28, separated and fed one by one by a pair of retard rollers 29, and is image-formed at a predetermined timing by a pair of registration rollers 19.
Sent to.

The images formed on the photosensitive drums 6a to 6d of the respective image forming stations are sequentially transferred by the well-known image forming process in the same manner as described above. The heat and pressure are applied to fix the image, and the image is discharged onto a discharge tray 23 outside the apparatus.

Here, the air blowing means for cooling the sheet material S after the heat fixing by the fixing device 20 will be described in detail with reference to FIGS.

As shown in FIG. 1, a discharge roller pair 32 is disposed downstream of the fixing device 20 in the transport direction, receives the sheet material S from the fixing device 20, and transfers the sheet material S to the discharge tray 23 which is further downstream. The sheet material S is transported and discharged.

Above the fixing device 20, a heat exhaust fan 30
Is provided, and the stay 33 and the stay 36 can be used as ducts to discharge air near the fixing device 20 to the outside of the apparatus.

The air exhausted by the heat exhaust fan 30 is divided into two directions as shown by arrows in FIG. And cooling port 3 as the first ventilation path
5b is discharged from two places.

The air discharged from the cooling port 35b is higher than the outside air by about 10 ° C. due to heat generated from the fixing device 20,
The effect of cooling the sheet material S is sufficient.

The wind discharged from the heat discharge port 35a is substantially the same width as the sheet width, and the wind direction regulating plate 62 as the wind direction regulating portion whose direction can be switched is in the state shown in FIG. 1 (first position). ) Is blown out in a substantially horizontal direction along the wind direction regulating plate 62 to cool the upper surface of the entire sheet material stacked on the upper surface of the paper discharge tray 23.

The wind direction restricting plate 62 is connected to the wind direction changing solenoid 63 via a rod 65 on the far side of the sheet width, and the downward direction position (first position) as shown in FIG. 2 position).

On the other hand, between the heat exhaust fan 30 and the heat exhaust port 35a, there is provided a shutter 67 as an opening / closing means having a slit having substantially the same width as the heat exhaust port 35a. The shutter 67 is connected to a shutter solenoid 64 via a link 66, and in the state of FIG.
When the shutter solenoid 64 is sucked in the state shown in FIG. 2 without preventing the wind from flowing out of the nozzle, the shutter is moved to a position almost blocking the heat exhaust port 35a.

A temperature sensor 61 as a temperature detecting means is provided on the upper surface of the paper discharge tray 23 so that the temperature of the sheet material S stacked on the paper discharge tray 23 can be detected. In this embodiment, the discharge tray 23 has a length that allows A3-size sheets to be stacked without completely protruding from the upper surface, and FIG. 1 shows a state where the A3-size sheets are loaded. .

On the other hand, FIG. 2 shows a state in which sheets of A4 size are stacked such that the long sides are in the depth direction.

In the control system diagram shown in FIG. 3, the original image information read by the CCD 4b is sent to a control unit 60 as control means, and lasers for magenta, cyan, yellow, and black image forming stations are accordingly transmitted. Control signals are sent to the units 11a, 11b, 11c, 11d.

The control unit 60 selects a paper cassette based on the paper size and the number of copies input by the user through the operation unit (sheet material setting means, number setting means, size setting means) 69, and selects the specified number of sheets. Perform a copy operation.

In the present embodiment, the number of copies can be set from 1 to 999. Further, in the copying machine according to the present embodiment, in order to optimally control the process conditions such as the transfer condition and the fixing speed according to the difference in the material and the thickness of the sheet material, the user usually sets the material of the sheet material. The user designates whether the sheet is paper or OHP on the operation unit 69.

Similarly, if the thickness of the sheet material is ordinary paper,
The operation unit 69 specifies whether the thin paper has a basis weight of g / m ² or less. Further, the control unit 60 includes a sheet material S from a temperature sensor 61 provided on the paper discharge tray 23.
Temperature information is also sent.

Further, the control unit 60 adjusts the voltage applied to the exhaust heat fan 30 to a standard voltage of 24 V and a high output voltage.
The air flow rate can be changed by switching between two types of 8 V.

The operation of the color copying machine of the present embodiment having the above configuration will be described.

In general, the phenomenon that the toner fixed on the sheet material S on the discharge tray 23 sticks to the sheet material stacked thereon becomes more likely to occur as the amount of the toner transferred to the sheet material increases. .

In the present embodiment, the control unit 60 adjusts the toner amount on the sheet material for each color over the entire surface of the sheet material.
When the image is 1.2 times or less of the one-color full-area solid image, the voltage applied to the exhaust heat fan 30 is supplied to the power supply 68 by 24 times the standard voltage.
When V is 1.2 times or more, the voltage is controlled to 28 V for high output.

By controlling in this manner, the operating air volume of the exhaust heat fan 30 can be reduced to a necessary minimum air volume in a normal case, and the user is not bothered by the operating noise of the fan.

On the other hand, especially when copying an image having a high image density and a large amount of applied toner, the operating voltage of the heat discharging fan 30 is increased to discharge the image from the cooling port 35b onto the sheet discharging tray 23. The air volume increases, cooling the sheet material S,
There is no sticking between the sheet materials and no toner stain on the back surface of the sheet material.

In the present embodiment, the air volume from the cooling port is controlled by the voltage applied to the exhaust heat fan 30 in this way. Instead, a plurality of fans are provided, and a part of the fan is normally used. A method of using only the fan and cooling the sheet material by all the fans only when the amount of applied toner is large may be adopted.

Even with such a configuration and operation, it is possible to normally prevent noise from the apparatus and prevent sticking of the sheet material.

In this embodiment, the following control is further performed.

The control unit 60 controls the OHP based on the sheet material information input by the user, regardless of the amount of toner applied.
Is a transfer material, the voltage applied to the exhaust heat fan 30 is set to 28 V for high output.

OHP is highly adhesive to high-temperature toner, so that sheet materials tend to stick to each other.
With such control, the OHP sheets are sufficiently cooled and do not stick to each other.

Further, when thin paper of 60 g / m ² or less is used as a recording material based on the thickness information of the sheet material input by the user, the control section 60 applies the heat to the heat exhaust fan 30 regardless of the amount of toner applied. Since the applied voltage is 28 V for high output, the sticking of the sheet material can be similarly prevented.

By controlling in this manner, the fan is operated at the required high output only when copying OHP or thin paper that is not frequently used, so that the noise given to the user can be minimized.

In the present embodiment, the following control is further performed to prevent sticking of the sheet material. When the number of continuous copies input from the operation unit 69 is 100 or more, the control unit 60 controls the output of the power supply 68 to 28 V for high output regardless of the amount of applied toner and the material of the transfer sheet. .

At the time of continuous copying, sheets are stacked one on another before the sheets stacked on the discharge tray 23 are sufficiently cooled. It was easy for the sheet materials to stick together, but by controlling as described above, the fan airflow was increased as necessary only during large-volume continuous copying, which was infrequently used, minimizing noise to the user. Can be

Further, in the present embodiment, the following control is also performed. Even if the above control is performed,
In rare cases, the temperature of the sheets loaded on the paper output tray rises more than intended due to fluctuations in the outside air temperature, deterioration of the durability of the exhaust heat fan, and increased loss due to contamination of the exhaust port. Was.

Even in such a case, in order to prevent sticking of the sheet material, when the temperature of the sheet material output by the temperature sensor 61 provided on the upper surface of the paper discharge tray becomes 60 ° C. or more, the amount of applied toner, the sheet The voltage applied to the exhaust heat fan 30 is set to 2 for high output regardless of the material, thickness and number of copies.
Control to increase to 8V.

With the control using only the temperature sensor 61, the first ten sheets may be slightly sticky or the sheet material may be slightly stained due to a time response delay. By performing the control in combination with the control based on the applied amount, the material, the thickness, and the number of copies, it is possible to minimize the sticking and dirt of the sheet material even when the fan has a failure.

In this embodiment, the following control is further performed. In FIG. 1, A3
FIG. 2 shows a state in which the sheet material is placed, but as shown in FIG. 2, when a small-size sheet of A4 or smaller is placed, the surface area in contact with the outside air with respect to the total volume of the loaded sheet material. When the direction of the cooling air as shown in FIG. 1 is used for cooling, the temperature of the sheet material rises, and sticking easily occurs.

In this case, the cooling of the sheet material was insufficient only by increasing the voltage of the fan to 28 V. Therefore, in addition to increasing the voltage to 28V, the control unit 60 sends a drive current from a power supply (not shown) to the shutter solenoid 64,
By pulling the link 66, the shutter 67 is moved to the position shown in FIG.

At the shutter position shown in FIG. 2, the entire amount of the air blown out of the heat exhaust fan 30 does not come out of the heat exhaust port 35a but goes out of the cooling port 35b, and the wind speed and the air volume increase. In the case of the present embodiment, the wind speed has increased from 1.0 m / s to 1.8 m / s. By performing such control, the cooling of the sheet material can be performed more effectively.

On the other hand, at this time, the exhaust resistance is increased and the suction amount of the exhaust heat fan 30 is slightly reduced by the absence of the air blowing path which goes straight from the exhaust heat fan 30. But,
The negative effect of the decrease in the suction amount of the exhaust heat fan 30 is that the outside air temperature is 3
When the copying machine has been operated for 1 hour or more in the environment of 0 ° C,
Since the image density is reduced below the standard due to the temperature rise around the process unit, there is almost no problem in practical use.

If this is also avoided, it is possible to add a temperature sensor for monitoring the temperature rise inside the apparatus, and if the temperature exceeds a specified value, it is possible to take a method such as reducing the copying speed.

However, simply changing the air flow path and increasing the amount of cooling air is still insufficient cooling, so the following control is further added.

The length of the transfer sheet is A4 width or less (210 m
m or less), a current is applied from a power supply (not shown) to the wind direction switching solenoid 63 by a command from the control unit 60,
As shown in FIG. 2, the rod 65 is pushed downward, and the wind direction regulating plate 62 is directed downward. At this time, the wind from the cooling port 35b is directed downward along the wind direction regulating plate 62,
The cooling capacity is increased because it is concentrated on the sheet length of A4.

By controlling in this manner, sticking can be effectively prevented even when the paper length is short and heat is easily stored.

In this embodiment, a heat exhaust fan for exhausting heat in the apparatus is used as a cooling means for the sheet material.
However, the present invention is not limited to this. For example, an air blowing means for applying air to the sheet material to cool it may be provided separately from the exhaust heat fan.

The cooling means is not limited to a fan, but may be any as long as it blows air to the sheet material to cool it.

In this embodiment, a full-color copying machine has been exemplified as an image forming apparatus to which the present invention is applied.
The present invention is not limited to this, and the same effect can be obtained by applying the present invention to other image forming apparatuses such as a printer and a facsimile machine.

[0084]

As described above, according to the present invention,
Depending on the state of the sheet material loaded on the sheet material loading section,
By providing the control means for controlling the blowing conditions of the blowing means, it is possible to effectively cool the sheet material as necessary, so that sticking between the sheet materials and toner stain on the back surface of the sheet material occur. And the noise caused by the blowing means and the power consumption of the blowing means can be suppressed, and it is possible to provide a high quality image forming apparatus in which the stacking performance on the sheet material stacking section is stabilized. .

Further, the control means controls the air blowing conditions of the air blowing means based on the amount of toner, the thickness or material of the sheet material, the number of sheets, the temperature and the size of the sheet material. The sheet material can be cooled.

Further, since the control means controls the air blowing means so as to change the amount of air blown to the sheet material stacked on the sheet material stacking section, the cooling effect of the sheet material can be surely enhanced.

Further, the control means changes the amount of air blown in the second air path of the air blowing means to change the amount of air blown to the sheet material stacked on the sheet material stacking unit. It is possible to reduce the cost, reduce the size, and increase the air flow while suppressing the noise.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a sheet material discharge unit of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a sheet discharging section of the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is a control system diagram illustrating a control method of the image forming apparatus according to the embodiment of the present invention.

FIG. 4 is a schematic sectional view of the image forming apparatus according to the embodiment of the present invention.

FIG. 5 is a schematic sectional view of a conventional image forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier main body 2 Document automatic feeder 3 Platen glass 4 Reader part 5 Image forming part 5M, 5Y, 5C, 5B Image forming station 6a-6d Photoreceptor drum 7a-7d Charger 8a-8d Developing device 9a-9d Cleaning device DESCRIPTION OF SYMBOLS 10 Belt conveyance part 10a-10d Transfer device 11 Laser unit 12,13 Cassette 14 Feeding part 15 Feeding deck 16 Pickup roller 17 Retard roller pair 18 Transport roller pair 19 Registration roller pair 20 Fixing device 21 Flapper 22 Discharge roller pair 23 Discharge Tray 24 Re-feed roller pair 25 Reverse transport path 26 Reverse transport roller pair 27 Intermediate tray 28 Pick-up roller 29 Retard roller pair 30 Heat exhaust fan 32 Paper exhaust roller pair 33, 36 Stay 35 Exterior cover 35a Heat exhaust port 35b Cooling port 60 Control unit First temperature sensor 62 wind direction regulating plate 63 the wind direction changing solenoid 64 shutter solenoid 65 rod 66 links 67 shutter 68 power 69 operating unit

Continued on the front page F-term (reference) 2H027 DA11 DB09 DC19 DE10 ED19 FA02 FA05 FA15 FA28 FA30 FA37 FB13 JA11 JB14 JB15 JB16 JB24 JB27 JB28 JC08 JC11 3F049 FA05 FA08 LA02 LB03 9A001 JJ35 KK29 KK32 KK42

Claims (11)

[Claims] An image forming means for developing an electrostatic latent image formed on an image carrier with toner to form an image on a sheet material, and loading the sheet material on which an image is formed by the image forming means A sheet material stacking section to be cooled, and air blowing means for exhausting air inside the apparatus to the outside of the apparatus and sending air to the sheet material stacked in the sheet material stacking section to cool the sheet material. The image forming apparatus according to claim 1, further comprising: a control unit configured to control a blowing condition of the blowing unit according to a state of the sheet material stacked on the sheet material stacking unit. 2. The image forming apparatus according to claim 1, wherein the control unit controls a blowing condition of the blowing unit based on an amount of toner on a sheet material formed as an image by the image forming unit. Image forming apparatus. 3. A sheet material setting means capable of setting a thickness or a material of a sheet material on which an image is formed, wherein the control means controls the thickness or the material of the sheet material set by the sheet material setting means. 3. A blowing condition of the blowing means is controlled based on the blowing condition.
An image forming apparatus according to claim 1. 4. A sheet number setting means capable of setting the number of sheet materials for forming an image, wherein the control means sets a blowing condition of the blowing means based on the number of sheet materials set by the sheet number setting means. The image forming apparatus according to claim 1, wherein the control is performed. 5. A temperature detecting device for detecting a temperature of the sheet material stacked on the sheet material stacking section, wherein the control device is configured to control the temperature of the sheet material based on the temperature of the sheet material detected by the temperature detecting device. The image forming apparatus according to claim 1, wherein a blowing condition of the blowing unit is controlled. 6. A size setting unit capable of setting a size of a sheet material on which an image is formed, or a size detection unit detecting a size of the sheet material on which an image is formed, wherein the control unit includes the size setting unit or the size. 6. The image forming apparatus according to claim 1, wherein the air blowing condition of the air blowing unit is controlled based on the size of the sheet material set or detected by the detecting unit. 7. The air blowing means includes a wind direction restricting section that takes a first position for sending air to the entire area of the sheet material stacking section and a second position for sending air to a partial area of the sheet material stacking section. Wherein the control means controls the air blowing means to change the position of the wind direction regulating part based on the size of the sheet material set or detected by the size setting means or the size detecting means. The image forming apparatus according to claim 6. 8. The apparatus according to claim 1, wherein said control means controls said blowing means so as to change a blowing amount for the sheet material stacked on said sheet material stacking section.
The image forming apparatus according to claim 1. 9. The air supply unit includes a plurality of fans, and the control unit changes the number of fans to be operated among the plurality of fans to change the amount of air blown to the sheet material. Item 10. The image forming apparatus according to Item 8. 10. The air blowing means includes a first air blowing path for sending air to the sheet material stacked on the sheet material stacking section, and a second air blowing path for exhausting air inside the apparatus to the outside of the apparatus. 10. The image forming apparatus according to claim 8, wherein the control unit changes an air blowing amount of the second air blowing path to change the air blowing amount for the sheet material. 11. 11. The air blowing means includes an opening / closing means for opening and closing the second air blowing path, and the control means controls the opening / closing means to change an air blowing amount of the second air blowing path. Claim 1.
0. The image forming apparatus according to item 0.