JP2003307996A - Image forming apparatus with heat exhausting means - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To exhaust the heat of a fixing means that generates the heat and to prevent delivered sheet adhesion due to temperature elevation. <P>SOLUTION: A copying machine 100 is provided with an image forming portion 115 for forming a toner image on a sheet, a fixing device 122 for applying the heat to the sheet where the toner image is formed by the image forming portion 115 to fix the toner image on the sheet, a delivery portion 125 on which the sheet where the toner image is fixed by the fixing device 122 is delivered and stacked, and heat exhausting fans 157 and 158 provided in the vicinity of the fixing device 122 and the delivery portion 125 for exhausting air in the surroundings of the fixing device 122 and the delivery portion 125 from the right side 101b of a main body 101. There is provided air vents 162, 163 and 168 between the fixing device 122 and the heat exhausting fans 157, 158 and between the delivery portion 125 and the heat exhausting fans 157 and 158. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a copying machine / LBP.
The present invention relates to an image forming apparatus that forms a toner image on a sheet.

[0002]

2. Description of the Related Art Conventionally, there is an image forming apparatus as an apparatus for forming an image on a sheet, such as a copying machine and a laser beam printer (LBP).

FIG. 8 shows a copying machine which is an example of an image forming apparatus. An original table 2 made of a transparent glass plate is fixedly provided on the main body 1 of the copying machine 10. The document pressing plate 3 is configured to press and fix the document D placed on the document table 2 at a predetermined position on the document table 2 with the image surface facing downward. Below the document table 2, an optical system including a lamp 4 for illuminating the document D, reflecting mirrors 5, 6, 7 for guiding the reflected light image of the document D to the image processing unit 8, and an imaging lens 11. Is provided. The lamp 4 and the reflecting mirrors 5, 6 and 7 move in the direction of arrow a at a predetermined speed to scan the document D.

The image forming section 15 includes a photosensitive drum 12, a charging device 13 for uniformly charging the surface of the photosensitive drum 12, a developing device 14 for forming a toner image on the photosensitive drum 12, and a developing device for developing the surface of the photosensitive drum 12. A transfer charging device 19 that transfers the toner image thus transferred onto the sheet S, a separation charging device 20 that separates the sheet S onto which the toner image has been transferred from the photosensitive drum 12, and a toner image after transferring the toner image remains on the photosensitive drum 12. A cleaner 26 for removing toner is provided. Photosensitive drum 1
2 is adapted to develop an electrostatic latent image formed on the surface of the photosensitive drum 12 charged by the charger 13 by the optical image emitted from the laser unit 9 and transfer it to the sheet S. The sheet S is supplied from the sheet cassette 27.

On the downstream side of the image forming section 15, a conveying section 21 for conveying the sheet S on which the toner image is transferred, and the toner image on the sheet S conveyed by the conveying section 21 are fixed to the sheet as a permanent image. The fixing device 22 and the discharging roller pair 24 for discharging the sheet S on which the toner image has been fixed by the fixing device 22 from the copying machine main body 1 are sequentially arranged. A discharge unit 25 that receives the sheet S discharged by the discharge roller pair 24 is provided outside the copying machine main body 1.

As shown in FIG. 9, the copying machine also includes a copying machine 16 having an in-cylinder sheet discharge structure for discharging sheets into the cylinder in order to save space. The image forming process of the copying machine 16 is almost the same as that of the copying machine 10 shown in FIG. 8 except that the sheet conveying path 53 of the transfer portion guides the sheet S in the vertical direction. A transfer roller 50 is used instead of the transfer charger 19 shown in FIG. Copier 16 of FIG.
Is provided with a sheet conveyance path 53 on the right side of the apparatus main body 1. Therefore, as shown in FIG. 9, the fan 54 is provided on the left side surface of the apparatus body 1 so that the air in the apparatus body flows from the right side to the left side of the apparatus body 1.

There is also a copying machine 28 in which a rotary developing unit 51, an intermediate transfer belt 52 and the like are added for forming a color image as shown in FIG. This copier 28
Uses a charging roller 60 instead of the charger 13 shown in FIG.

Fixing device 22 of each copying machine 10, 16, 28
Is configured to nip and convey the sheet while heating and pressing the sheet to fix the toner image on the sheet.

In the constituent elements of the copying machines 16 and 28, the constituent elements that operate in the same manner as the constituent elements of the copying machine 10 are designated by the same reference numerals as those of the copying machine 10 and the description thereof will be omitted. Omit it.

[0010]

Here, as shown in FIG. 10, when a fan 55 is provided on the left side surface of the apparatus main body 1 so that the airflow flows from right to left of the apparatus main body 1, The heat generated from the fixing device 22 may flow around the rotary developing unit 51, the intermediate transfer belt 52, and the like. Since the rotary developing unit 51 and the intermediate transfer belt 52 are process units that use toner, if the temperature rises excessively, problems such as toner blocking and toner fusion may occur.

Further, as compared with the copying machine 10 for laterally conveying the sheet shown in FIG. 8, the copying machines 16 and 28 for vertically conveying the sheet shown in FIGS. 9 and 10 have the toner on the sheet. Since the distance between the fixing device 22 for fixing the image and the discharging unit 25 for discharging the sheet is short, the temperature of the sheet discharged to the discharging unit 25 is high, and the sheets may stick to each other due to the toner image that is not sufficiently cooled. Yes (hereinafter, this phenomenon is referred to as "paper ejection adhesion").

Further, the fan 56 of the copying machine 10 shown in FIG.
Is disposed in the vicinity 61 of the fixing device 22 on the rear side of the apparatus main body 1. The fan 54 of the copying machine 16 shown in FIG. 9 is arranged near the left side surface 62 of the apparatus main body 1. The fan 57 of the copying machine 28 shown in FIG.
It is arranged in the vicinity 63 of 2. Therefore, the fan 56,
When exchanging 54 and 55 due to some trouble, the serviceman had to go around to the left side or rear side of the apparatus main body 1 to perform the exchange work. Furthermore, not only does the maintenance work take time, but the copying machines 10, 1
6,28 had to be stopped for a long time (the downtime was long).

Further, the copying machine 16 for vertically conveying the sheet S shown in FIG. 9 along the sheet conveying path 53 can convey the sheet in an unstable state because the leading end of the sheet falls to the left and right during the conveyance. Many. In particular, the sheet is likely to curl under the influence of heat and pressure of the fixing device 22 until it passes through the fixing device 22 and reaches the discharging portion 25, so that it is necessary to stably convey the sheet.

The fan 57 of the copying machine 28 shown in FIG.
Since the fixing device 22 is provided on the rear side of the apparatus main body 1 and the fixing device 22 is longly arranged in the direction intersecting the sheet conveying direction (front and back direction of the paper surface of FIG. 10), the fixing device 22 is provided. Since the heat of the fixing device 22 is discharged at one end of the above, the heat discharging efficiency of the fixing device 22 is poor.

The present invention provides an image forming apparatus that discharges heat from a fixing unit that generates heat to prevent discharge adhesion due to temperature rise.

[0016]

An image forming apparatus with a waste heat means that achieves the above object has an image forming means for forming a toner image on a sheet, and a sheet on which the toner image is formed by the image forming means. A fixing unit that applies heat to fix the toner image on the sheet, a discharge stacking unit that discharges and stacks the sheet on which the toner image is fixed by the fixing unit, a fixing unit, and a discharge stacking unit. A waste heat means disposed near the fixing means and discharging the air around the fixing means and the air around the discharge and stacking means from the side portion of the apparatus main body. And a vent hole between the discharging and loading means and the waste heat means.

The discharging and stacking means of the image forming apparatus with the waste heat means of the present invention is disposed above the fixing means, and a sheet conveying path facing up and down is provided between the fixing means and the discharging and stacking means. The sheet conveying path has a vent hole.

In the image forming apparatus with the waste heat means of the present invention, when the sheet is conveyed through the sheet conveying path, the waste heat means is removed as the sheet approaches the discharging and stacking means from the fixing means. Waste heat control means is provided for controlling and reducing the amount of air discharged from the waste heat means.

The waste heat means of the image forming apparatus with the waste heat means of the present invention is provided on a lid provided on a side portion of the apparatus body.

The lid of the image forming apparatus with the waste heat means of the present invention is provided so as to be openable and closable around the inner side of the side of the apparatus main body as the center of rotation.

In order to achieve the above object, the image forming apparatus with the waste heat means of the present invention discharges the fixing roller for fixing the toner image formed on the sheet to the sheet and the sheet on which the image is fixed by the fixing roller. A discharge roller, a stacking tray for stacking the sheets discharged by the discharge roller, a guide for guiding the sheet from the fixing roller to the discharge roller, a casing in which the fixing roller and the guide are stored, and the casing. The fixing tray is provided on the body and is arranged on the opposite side of the discharge tray side ventilation hole for taking in air from the space above the stacking tray to the vicinity of the guide and the guide tray sandwiched between the ventilation hole and the discharge tray side ventilation hole. And a fan that discharges air near the roller and near the guide to the outside of the housing.

The guide of the image forming apparatus with the waste heat means of the present invention guides the sheet upward.

Above the stacking tray and the ventilation holes on the stacking tray side of the image forming apparatus with waste heat means of the present invention,
Image reading means is provided.

The guide of the image forming apparatus with the waste heat means of the present invention is provided with a vent hole for allowing air to flow from the vent tray side vent hole to the fan.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION A copying machine which is an image forming apparatus according to an embodiment of the present invention will be described below with reference to the drawings. The image forming apparatus of the present invention generates heat in the apparatus body, for example,
Equipped with a fixing device. In such an image forming apparatus,
In addition to copying machines, there are printers and the like. Therefore, the image forming apparatus of the present invention is not limited to the copying machine.

(Copier of First Embodiment) The copier of the first embodiment will be described with reference to FIGS. 1, 2 and 3. FIG. 1 is a plan view of the copying machine. FIG. 2 is a front sectional view of the copying machine. FIG. 3 is a detailed view from the fixing device 122 to the discharging portion 125.

As shown in FIG. 2, the main body 1 of the copying machine 100.
On the upper part of 01, there is a platen 102 made of a transparent glass plate.
Is fixedly provided. The original pressure plate 103 is the original table 1
A document D placed at a predetermined position 02 with the image surface facing downward is pressed and fixed on the document table 102. Below the document table 102, a lamp 104 for illuminating the document D, reflecting mirrors 105, 106, 107 for guiding the illuminated optical image of the document D to an image processing unit (not shown), and an imaging lens 111 are provided. An optical system (image reading means) is provided. The lamp 104 and the reflection mirror 10
Reference numerals 5, 106, and 107 move in the direction of arrow b at a predetermined speed to scan the document D.

The image forming section 115 includes a photosensitive drum 112.
A charging roller 160 for uniformly charging the surface of the photosensitive drum 112, a rotary developing unit 151 for forming a toner image on the photosensitive drum 112, and an intermediate transfer belt to which the developed toner image is transferred on the surface of the photosensitive drum 112. 15
2, a transfer roller 150 that transfers the toner image on the intermediate transfer belt 152 to the sheet S, and a cleaner 1 that removes the toner remaining on the photosensitive drum 112 after the toner image is transferred.
26 and so on. The photosensitive drum 112 is adapted to develop an electrostatic latent image formed by a light image emitted from the laser unit 109 on the surface of the photosensitive drum 112 charged by the charging roller 160 and transfer it to the intermediate transfer belt 152. There is. The toner image on the intermediate transfer belt 152 is transferred onto the sheet S by the transfer roller 150. The sheet S is sent out from the sheet cassette 127 by a pickup roller 128, separated by a retard roller pair 129 and sent out, and further conveyed by a pair of conveying rollers 130, 131, 132, 133, 13.
4 and the like are supplied to the transfer position.

A fixing device 122 for fixing the toner image on the conveyed sheet S as a permanent image on the downstream side in the conveying direction above the image forming portion 115, and a toner image is fixed on this fixing device 122 further above. A discharge roller pair 124 for discharging the formed sheet S from the copying machine main body 101 is arranged in order. A discharge unit (stacking tray) 125 that receives the sheets S discharged by the discharge roller pair 124 is provided outside the copying machine main body 101. The fixing device 122 is
Heat and press the sheet to fix the toner image on the sheet 1
It has a pair of fixing rollers 122a and 112b.

As shown in FIG. 1, the waste heat fans 157 and 158 are arranged on a jam handling door 159 (see FIG. 4) provided on the right side portion 101b of the main body 101 of the copying machine 100. An exhaust port 166 is formed in a portion of the jam processing door 159 to which the waste heat fans 157 and 158 are attached. As shown in FIG. 3, the left side portion of the main body 101 facing the waste heat fans 157 and 158 and the sheet conveying passage (guide).
Around the wall 153 a of the fixing unit 153 and the fixing device 122, for example, vent holes 162 a, 16 which are vent holes through which air passes.
A plurality of 2b, 163a, 163b, 164 and 168 are formed. In addition, as shown in FIG.
A plurality of intake ports 165 are formed in the la 1a to allow air to enter the main body 101 from the outside.

When the waste heat fans 157 and 158 rotate,
Outside air flows into the main body 101 of the copying machine 100 from the intake port 165 (see FIG. 2), passes through the ventilation port 168, and
It is discharged from the exhaust port 166. During this period, the image forming unit 11
5 and the air around the fixing device 122 are also discharged together with the outside air.

Further, the fixing device 22 is arranged long in a direction intersecting with the sheet conveying direction. That is, the fixing device 22 is arranged long in the front and back direction of the paper surface of FIGS. As shown in FIGS. 1 and 2, the waste heat fans 157 and 158 are arranged obliquely above the fixing device 122 along the longitudinal direction of the fixing device 122. Therefore, the waste heat fans 157 and 158 can reliably discharge the heat of the fixing device 22 to the outside of the apparatus main body 101 to cool the fixing device 22.

On the other hand, the outside air is ventilated through the vents 162a, 162.
air flow 16 passing through b, 163a, 163b, 164
2, 163 are formed and exhausted from the exhaust port 166. Therefore, the sheet S having heat is heated, and the discharge unit 12
Vents 162a, 162 are also attached to the outside air stagnant in 5
b, 163a, 163b, 164, and exhaust port 1
Exhausted from 66. Therefore, the discharge unit 125, the sheets S stacked on the discharge unit 125, the fixing device 122, and the sheet conveying path 153 downstream thereof are cooled.

The waste heat fan is not limited to two and may be three or more. Further, it may be one. When there is one waste heat fan, it is preferable that the waste heat fan is provided so as to face the intermediate position in the longitudinal direction of the fixing device 122.

Further, the waste heat fan is provided with a jam processing door 159.
It is not always necessary to provide it. The waste heat fan may be provided in the apparatus main body 101.

As described above, the copying machine 100 according to the first embodiment.
From the vicinity of the fixing device 122, which is a heat source, to the waste heat fan 15
Since the air is immediately discharged by 7, 158, the air heated by the fixing device 122 hardly flows into other process units such as the rotary developing device 151 and the intermediate transfer belt 152. Furthermore, troubles such as toner blocking and toner fusion can be prevented, and efficient waste heat can be performed.

Further, the copying machine 100 of the first embodiment is
The waste heat fans 157 and 158 also discharge the air between the fixing device 122 and the discharging portion 125 to cool the sheet S. Therefore, the temperature of the sheet S in the discharging portion 125 is lowered,
It is possible to prevent paper ejection adhesion.

(Copier of Second Embodiment) A copier of the second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a plan view of the copying machine. FIG. 5 is a front sectional view of the copying machine.

The copying machine 200 of the second embodiment is different from that of the first embodiment in that the jam processing door 159 is provided in the apparatus main body 101 so as to be openable and closable, and the jam processing door 159 is provided with waste heat fans 157 and 158. The configuration is different from that of the copying machine 100. In the copying machine 200 of the second embodiment, the same parts as those of the copying machine 100 of the first embodiment are designated by the same reference numerals, and the description of those parts will be omitted.

The waste heat fans 157 and 158 are used in the copying machine 20.
It is disposed on the inner surface 159a of the jam handling door 159 on the right side surface of No. 0. In addition, the hinge portion 161 of the jam handling door 159
Is located on the back side of the copying machine 200, and rotatably supports the jam processing door 159 on the apparatus main body 101.

When a service person replaces the waste heat fans 157 and 158 due to some trouble or when performing maintenance on the waste heat fans 157 and 158, the service person rotates the jam processing door 159 around the hinge portion 161. Let it open. Then, the waste heat fans 157 and 158 can be replaced or maintenance work can be performed from the front of the copying machine 200, and the waste heat fans 157 and 158 can be performed.
It is possible to shorten the replacement work time or the maintenance work time. Moreover, the waste heat fans 157, 15
Since 8 is supported by the jam treatment door 159, maintenance work can be performed very easily. further,
Since the stop time of the copying machine 200 can be shortened,
The utilization efficiency of the copying machine 200 can be improved.

In addition, the copying machine 200 of the second embodiment is
It has the same features as the copying machine 100 of the first embodiment.

Also in the copying machine 200 of the second embodiment, the waste heat fan is not limited to two and may be three or more. Further, it may be one. When there is one waste heat fan, it is preferable that the waste heat fan is provided so as to face the intermediate position in the longitudinal direction of the fixing device 122.

(Copying Machine of Third Embodiment) The copying machine of the third embodiment will be described with reference to FIGS. 6 and 7. 6 and 7
FIG. 9 is a cross-sectional view of a waste heat fan and its periphery of the copying machine 300 of the third embodiment. In the copying machine 300 of the third embodiment, the same parts as those of the copying machine 100 of the first embodiment are designated by the same reference numerals, and the description of those parts will be omitted.

In the copying machine 300 of the third embodiment, the waste heat fans 157 and 158 are controlled by the waste heat controller 169 so that the number of rotations can be changed in accordance with the sheet conveyance timing. .

When the copying machine 300 carries out the image forming operation, the waste heat fans 157 and 158 cause the fixing device 122 and the discharging portion 12 to operate.
Air near 5 is discharged to the right of the apparatus main body 101. At this time, the air flows on the wall 15 of the sheet conveying path 153.
3a through the vent 164 to the outer surface 15 of the jam handling door 159
9b, the sheet can follow the wall 153a of the sheet conveying passage 153 as shown in FIG.

However, depending on the size and material of the sheet, the sheet may not be conveyed due to being adsorbed on the wall 153a, or as shown in FIG. 7, the vertical sheet conveying passage 153 may be bent due to its own weight and may not be conveyed smoothly. May occur.

Therefore, when the sheet passes through the suction area from the fixing unit 122 to the discharging unit 125, the waste heat control unit 169 causes the leading edge of the sheet to move from the fixing unit 122 to the discharging roller pair 1.
As it approaches 24, the waste heat fans 157 and 158
Slow down the rotation of. The waste heat control unit 169 also controls the waste heat fans 157, 1 depending on the quality of the sheet and the size of the sheet.
Change the rotation of 58.

Therefore, the copying machine 300 can smoothly convey the sheet in a stable state without sucking and closely adhering the sheet to the wall 153a.

Further, the copying machine 300 can stably convey the sheet along the wall 153a without tilting the sheet leftward or rightward in the sheet conveying passage 153.

In addition, the copying machine 300 of the third embodiment is
It has the same features as the copying machine 100 of the first embodiment.

As described above, the copying machines (image forming apparatuses) 100, 200 and 300 of this embodiment form an image forming section (image forming means) 115 for forming a toner image on a sheet.
Then, a fixing device (fixing unit) 122 that applies heat to the sheet on which the toner image is formed by the image forming unit 115 to fix the toner image on the sheet, and the sheet on which the toner image is fixed by the fixing device 122 are discharged. The discharging section (discharging and stacking means) 125 to be stacked, the fixing unit 122 and the discharging section 125 are provided in the vicinity of the fixing section 122, and the air around the fixing section 122 and the air around the discharging section 125 are provided on the right side of the apparatus main body 101 ( Waste heat fan (waste heat means) 15 discharged from the side portion 101b
7, 158, and the fixing device 122 and the waste heat fan 15
7, 158, and the discharge part 125 and the waste heat fan 15
Vents 162a, 162b, 163 between 7, 158
a, 163b, 164 are provided.

With this configuration, the copying machines 100, 20
In Nos. 0 and 300, the heat generated from the fixing device 122 is immediately discharged from the right side portion 101b of the apparatus main body 101, so that it does not flow into other process units and toner blocking / toner fusion occurs. It is possible to prevent troubles such as wearing and efficiently perform waste heat. Further, the temperature of the sheet in the discharge section 125 can be lowered, and the discharge discharge adhesion can be prevented.

Copiers 100, 200, 30 of this embodiment
The discharge unit 125 of 0 is disposed above the fixing device 122,
A sheet transporting path (sheet transporting path) 153 facing up and down is provided between the fixing device 122 and the discharging portion 125, and the sheet transporting path 153 has ventilation holes 163b and 164.

With this configuration, the copying machine 1 of this embodiment
00, 200, and 300 indicate a sheet conveying path 15
The sheet can be conveyed in a stable state by reliably following the sheet No. 3. Further, since the sheet is cooled and stacked on the discharge section 125 while the sheet passes between the fixing device 122 and the discharge section 125, it is possible to prevent the discharged sheet from adhering.

Copiers 100, 200, 30 of this embodiment
0 controls the waste heat fans 157 and 158 as the sheet approaches the discharge unit 125 from the fixing device 122 when the sheet is conveyed through the sheet conveying passage 153,
A waste heat control unit (waste heat control means) 169 for reducing the amount of air discharged from the waste heat fans 157 and 158 is provided.

With this configuration, the copying machine 1 of this embodiment
00, 200, 300 can change the rotation speed of the waste heat fans 157, 158 when the sheets pass through the suction area by the waste heat fans 157, 158 from the fixing device 122 to the discharge portion 125, and thus the sheets can be changed. The sheet can be stably conveyed without being sucked too much.

Copiers 100, 200, 30 of this embodiment
0, the waste heat fans 157 and 158 are connected to the apparatus main body 1
It is provided on the jam handling door (lid) 159 provided on the right side portion (side portion) 101b of 01.

With this configuration, the copying machine 1 of this embodiment
00, 200, and 300 are the right side portion 10 of the apparatus body 101.
The jam treatment door 159 can be easily removed from the 1b to easily maintain the waste heat fans 157 and 158.

In the copying machine 200 of this embodiment, the jam handling door 159 has the right side portion (side portion) 1 of the apparatus main body 101.
It is provided so as to be openable and closable with the back side of 01b as the center of rotation.

With this configuration, the copying machine 2 of this embodiment
00 is a waste heat fan 15 from the front of the apparatus main body 101 when the service person opens the jam processing door 159.
Since 7, 158 can be accessed, service work can be shortened and downtime of the image forming apparatus can be shortened.

[0062]

In the image forming apparatus of the present invention, the heat generated from the fixing means is immediately discharged from the side portion of the main body of the apparatus, so that the heat does not flow into other process units. Therefore, troubles such as toner blocking and toner fusion can be prevented, and efficient waste heat can be performed.

Further, since the air between the fixing means and the discharging and stacking means is discharged, the sheet can be cooled,
The temperature of the sheet in the discharge stacking unit can be lowered, and the discharge discharge adhesion can be prevented.

[Brief description of drawings]

FIG. 1 is a plan view of an intermediate portion in a height direction of a copying machine which is an image forming apparatus according to a first exemplary embodiment of the present invention.

FIG. 2 is a front sectional view of a copying machine that is an image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view around a waste heat fan of a copying machine that is an image forming apparatus according to the first exemplary embodiment of the present invention.

FIG. 4 is a plan view of an intermediate portion in a height direction of a copying machine which is an image forming apparatus according to a second exemplary embodiment of the present invention.

FIG. 5 is a front sectional view of a copying machine that is an image forming apparatus according to a second embodiment of the present invention.

FIG. 6 is a sectional view around a waste heat fan of a copying machine that is an image forming apparatus according to a third embodiment of the present invention.

7 is a view showing a state in which wrinkles are generated in the sheet in the cross-sectional view around the waste heat fan of FIG.

FIG. 8 is a front sectional view of a copying machine that is a conventional image forming apparatus.

FIG. 9 is a front sectional view of a copying machine which is a conventional image forming apparatus.

FIG. 10 is a front sectional view of a copying machine that is a conventional image forming apparatus.

[Explanation of symbols]

S sheet D originals 100, 200, 300 copying machine (image forming apparatus) 101 copying machine main body (apparatus main body) 101a left side 101b right side (side) 115 image forming section (image forming means) 122 fixing device (fixing means) ) 125 discharge section (discharge stacking means) 153 sheet conveying passage (sheet conveying path) 153a wall 157 waste heat fan (waste heat means) 158 waste heat fan (waste heat means) 159 jam treatment door (lid) 159a jam treatment door Inner surface 159b Outer surface 161 of jam handling door Hinge portions 162, 163 Air currents 162a, 162b, 163a, 163b, 164
Vent (vent) 165 Inlet 166 Exhaust 168 Vent 169 Waste heat control unit (waste heat control means)

Continued front page    F term (reference) 2H027 JA11 JB15 JB17 JB24 JC08                       JC13                 2H033 AA36 AA37 BA10 BA29 CA22                       CA53                 2H171 FA03 FA06 FA19 FA21 FA22                       FA28 GA01 GA11 GA12 GA23                       HA02 HA19 HA23 HA24 NA03                       NA05 QA02 QA08 QA24 QB03                       QB15 QB34 QC03 QC36 RA01                       RA05 RA09 SA11 SA14 SA18                       SA19 SA20 SA22 SA26 SA31                       WA11 WA12 WA16

Claims (9)

[Claims] 1. An image forming unit for forming a toner image on a sheet; a fixing unit for applying heat to the sheet on which the toner image is formed by the image forming unit to fix the toner image on the sheet; Discharge stacking means for discharging and stacking the sheet on which the toner image has been fixed by the fixing means, and air around the fixing means and the discharge stacking provided near the fixing means and the discharge stacking means. Waste heat discharging means for discharging air around the means from the side part of the apparatus main body, and a vent hole between the fixing means and the waste heat means and between the discharge stacking means and the waste heat means. An image forming apparatus with a waste heat unit. 2. The discharging and stacking means is disposed above the fixing means, and includes a sheet conveying path facing up and down between the fixing means and the discharging and stacking means, and the sheet conveying path is a vent hole. The image forming apparatus with a waste heat unit according to claim 1, further comprising: 3. When the sheet is conveyed through the sheet conveying path, the waste heat unit is controlled as the sheet approaches the discharge stacking unit from the fixing unit, and the air of the waste heat unit is controlled. The image forming apparatus with a waste heat unit according to claim 1 or 2, further comprising a waste heat control unit that reduces a discharge amount. 4. The image forming apparatus with a waste heat unit according to claim 1, wherein the waste heat unit is provided on a lid provided on a side portion of the apparatus main body. 5. The image forming apparatus with a waste heat unit according to claim 4, wherein the lid is provided so as to be openable and closable around a rear side of a side portion of the apparatus main body as a rotation center. 6. A fixing roller for fixing the toner image formed on the sheet to the sheet, a discharging roller for discharging the sheet on which the image is fixed by the fixing roller, and a stacking tray for stacking the sheet discharged by the discharging roller. A guide that guides the sheet from the fixing roller to the discharge roller; a housing that houses the fixing roller and the guide; and air that is provided in the housing and above the stacking tray that allows air to flow near the guide. A fan that is disposed on the opposite side of the discharge tray side ventilation hole that is taken in to the discharge tray side ventilation hole and the discharge tray side ventilation hole, and discharges air near the fixing roller and near the guide to the outside of the casing. And an image forming apparatus with a waste heat means. 7. The image forming apparatus with a waste heat unit according to claim 6, wherein the guide guides the sheet upward. 8. The image forming apparatus with a waste heat unit according to claim 6, wherein an image reading unit is provided above the stack tray and the ventilation hole on the stack tray side. 9. The waste heat means according to claim 6 or 7, wherein the guide is provided with a vent hole for allowing air to flow from the discharge tray side vent hole to the fan. Image forming apparatus.