JP2010107603A - Image forming apparatus and cooling device for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling device for an image forming apparatus, which prevents toner melting between paper and paper and prevents temperature rise in an original reading section due to heat radiation from the paper. <P>SOLUTION: The cooling device is provided in the image forming apparatus including a body 1, the original reading section 2, an image forming section 4, a fixing section 14 fixing an unfixed image formed on the paper by heating, a paper storing section 5, and an in-body ejection section 16 positioned at the upper part of the image forming section 4 under the original reading section 2, and opened as a section for taking out the paper in the body 1. The cooling device for the image forming apparatus, which cools the ejection space H of the in-body ejection section 16, includes a temperature detection section 17, a cooling section 18 and a controller 19. The controller 19 controls drive of the cooling section 18 in accordance with atmospheric temperature of the ejection space H of the in-body ejection section 16 detected by the temperature detection section 17 so as to cool the ejection space H of the in-body ejection section 16. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus including a fixing unit that fixes an unfixed image formed on a sheet by heating, and a cooling apparatus for the image forming apparatus.

  Generally, a fixing device is provided in an electrophotographic image forming apparatus such as a copying machine, a facsimile, a scanner, and a multifunction machine. In an electrophotographic image forming apparatus, a toner image formed on the surface of a photosensitive drum is transferred to a sheet to form an image. The fixing apparatus fixes the transferred toner image on a sheet with heat and pressure. .

In recent years, not only plain paper but also special paper such as thick paper subjected to surface treatment and special paper such as OHT has been used in various types of image forming apparatuses. Also, the number of printed sheets by the image forming apparatus tends to increase. Therefore, in order to obtain a stable fixability regardless of the increase in the number of sheets and the number of printed sheets, for example, a temperature sensor is provided near the fixing nip of the fixing device to detect the surface temperature of the sheet after fixing. A method of changing the fixing control temperature according to the temperature has been proposed (see Patent Document 1 and Patent Document 2).
JP 2003-280447 A JP 2006-10653 A

  When the toner image is fixed on the sheet by the fixing device, the sheet is heated and becomes high temperature. When such a high-temperature sheet is discharged and stacked on the discharge unit, the toner on the sheet in the discharge unit is close to the melting point. Then, there is a problem that the toners of the overlapping sheets in the discharge unit are fused and the sheets adhere to each other.

  Here, the apparatuses disclosed in Patent Document 1 and Patent Document 2 include a temperature sensor that detects the surface temperature of the paper after fixing. Therefore, for example, by providing a cooling device that cools the fixing device in conjunction with these sensors, it is considered that the above-described problem of toner welding between sheets can be dealt with.

  On the other hand, there is an image forming apparatus including an in-cylinder discharge unit that discharges paper under a document reading unit that reads image information. When a high-temperature sheet is discharged to the in-cylinder discharge portion of such an image forming apparatus, the temperature of the in-cylinder discharge portion rises because heat from the sheet is not easily diffused. As a result, the temperature of the document reading unit disposed on the upper part of the in-body discharge unit increases, which may cause further problems such as a decrease in the reading accuracy of the document reading unit and a decrease in the function of the electrical components.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a cooling device for an image forming apparatus that prevents toner fusion between sheets and prevents a temperature rise of a document reading unit due to heat radiation from the sheets.

  The cooling device for an image forming apparatus according to claim 1 includes a main body, a document reading unit that reads image information, an image forming unit that forms an image on a sheet based on image information of the document read by the document reading unit, A fixing unit that fixes an unfixed image formed on a sheet by heating, a sheet storage unit that stores a sheet to be supplied to the image forming unit, a lower part of the document reading unit, and an upper part of the image forming unit. A cooling device that is provided in an image forming apparatus including an in-cylinder discharge unit that is opened for taking out paper and in which a sheet on which an image is recorded is discharged, and cools the discharge space of the in-cylinder discharge unit, A temperature detection unit that detects the ambient temperature of the discharge space of the in-body discharge unit, a cooling unit that cools the discharge space, and a control unit that drives the cooling unit according to the ambient temperature.

  Here, the control unit controls the driving of the cooling unit according to the atmospheric temperature of the discharge space of the in-cylinder discharge unit detected by the temperature detection unit, and cools the discharge space of the in-cylinder discharge unit. Accordingly, it is possible to cool the paper discharged to the in-cylinder discharge unit and cool the document reading unit disposed on the in-cylinder discharge unit. From the above, it is possible not only to prevent toner fusion between sheets, but also to prevent an increase in the temperature of the document reading unit and prevent a decrease in the function of the document reading device that can be caused by the temperature increase.

  A cooling device for an image forming apparatus according to a second aspect is the cooling device for an image forming apparatus according to the first aspect, wherein the cooling unit has a cooling fan.

  Here, the cooling unit has a cooling fan to cool the discharge space of the in-cylinder discharge unit, to cool the paper discharged to the in-cylinder discharge unit, and the document reading unit disposed on the in-cylinder discharge unit. Cooling. Therefore, not only the toner fusion between the sheets can be prevented, but also the temperature reading of the document reading unit can be avoided and the deterioration of the function of the document reading device that can be caused by the temperature rise can be prevented.

  A cooling device for an image forming apparatus according to a third aspect is the cooling device for an image forming apparatus according to the first or second aspect, wherein the cooling unit is disposed in the main body, and the cooling air from the cooling unit is supplied to the in-cylinder discharge unit. It is sent out along the paper discharge direction.

  Here, since the cooling air is sent from the cooling unit to the in-body discharge unit along the paper discharge direction, a path through the discharge space is taken to cool the discharge space and to remove the heat in the discharge space from the main body. Can be squeezed out. Accordingly, it is possible to cool the paper discharged to the in-cylinder discharge unit and cool the document reading unit disposed on the in-cylinder discharge unit. From the above, it is possible not only to prevent toner fusion between sheets, but also to prevent an increase in the temperature of the document reading unit and prevent a decrease in the function of the document reading device that can be caused by the temperature increase.

  A cooling device for an image forming apparatus according to a fourth aspect is the cooling device for an image forming apparatus according to the first or second aspect, wherein the cooling portion is a lower portion of the document reading portion and faces the in-body discharge portion. Placed in.

  Here, the cooling air sent from the cooling unit cools the discharge space of the in-cylinder discharge unit, thereby cooling the paper discharged to the in-cylinder discharge unit and reading the document placed on the in-cylinder discharge unit. The part can be cooled. From the above, it is possible not only to prevent toner fusion between sheets, but also to prevent an increase in the temperature of the document reading unit and prevent a decrease in the function of the document reading device that can be caused by the temperature increase.

  A cooling device for an image forming apparatus according to a fifth aspect is the cooling device for an image forming apparatus according to the first or fourth aspect, wherein the control unit further controls the fixing temperature in the fixing unit according to the ambient temperature.

  Here, the control unit controls the driving of the cooling unit and further controls the fixing temperature of the fixing unit according to the atmospheric temperature of the discharge space of the in-cylinder discharge unit detected by the temperature detection unit. Therefore, not only the discharge space can be cooled, but also the paper whose temperature has already decreased can be discharged to the in-body discharge portion. Accordingly, it is possible to more efficiently prevent toner fusion between sheets and prevent deterioration of the function due to the temperature increase of the document reading unit.

  A cooling device for an image forming apparatus according to a sixth aspect is the cooling device for an image forming apparatus according to the first or fifth aspect, wherein the control unit further controls the sheet processing speed in accordance with the ambient temperature.

Here, the control unit controls the driving of the cooling fan and further controls the number of sheets processed in the image forming apparatus. Therefore, the temperature of the paper discharged to the in-body discharge portion can be lowered. Further, by simultaneously cooling the discharge space of the in-body discharge unit by the cooling unit, it is possible to more efficiently prevent toner fusion between sheets and prevent deterioration of the function due to the temperature increase of the document reading unit. Can do.
An image forming apparatus according to a seventh aspect includes a main body, a document reading unit that reads image information, an image forming unit that forms an image on a sheet based on image information of the document read by the document reading unit, and a sheet formed on the sheet A fixing unit that fixes a fixed unfixed image by heating, a paper storage unit that stores paper to be supplied to the image forming unit, a lower part of the document reading unit, and an upper part of the image forming unit. An in-body discharge unit that is opened for taking out and discharges a sheet on which an image is recorded, and a cooling device for an image forming apparatus according to claim 1.

  According to the present invention as described above, it is possible to prevent toner fusion between sheets discharged to the in-cylinder discharge portion, and it is possible to prevent a decrease in the function of the document reading apparatus caused by a temperature increase due to heat radiation from the sheets. .

1. First Embodiment [Overall Configuration]
FIG. 1 is a schematic cross-sectional view of a multifunction machine 1 as an image forming apparatus in which the first embodiment of the present invention is employed.

  The multifunction machine 1 includes a document reading unit 2 and a main body 3, and includes an image forming unit 4, a paper storage unit 5, a paper transport unit 13 that transports paper from the paper storage unit 5, and a fixing device 14. And an in-body discharge section 16. Furthermore, the multifunction device 1 includes a temperature detection unit 17, a cooling unit 18, and a control unit 19 as a cooling device. Note that the arrows in FIG. 1 indicate the sheet conveyance path.

  The document reading unit 2 is a part for reading image data of a document, and can read image data of a document on a contact glass (not shown).

  The image forming unit 4 is a part for forming an image on a sheet based on the image data of the document read by the document reading unit 2. The image forming unit 4 includes a photosensitive drum 6, a charging device 7, an exposure device 8, and a developing device 9. And a transfer roller 10 and a cleaning device 11. The photosensitive drum 6 is a member that forms an electrostatic latent image on the surface based on image data, and is a cylindrical member. The charging device 7 is a member that charges the surface of the photosensitive drum 6. The exposure device 8 is a member for irradiating the photosensitive drum 6 with laser light. The developing device 9 is disposed in the vicinity of the photosensitive drum 6 and supplies toner to the surface of the photosensitive drum 6. The developing device 9 stores toner therein. The transfer roller 10 is disposed to face the photosensitive drum 6 and transfers a toner image to a sheet. The cleaning device 11 collects residual toner.

  The fixing device 14 is disposed above the image forming unit 4 and is a part for fixing the toner image formed on the paper. The fixing device 14 includes a fixing roller 141 and a pressure roller 142 disposed to face each other. The fixing roller 141 incorporates a heat source such as a halogen lamp. Fixing is performed by inserting a sheet with unfixed toner through a nip portion where the fixing roller 141 and the pressure roller 142 face each other. Specifically, the toner image is pressed against the paper by the pressure of the pressure roller 142, and the toner image is melted by the heat of the fixing roller 141 to fix the toner image on the paper.

  The paper storage unit 5 stores paper to be supplied to the image forming unit 4.

  The paper transport unit 13 is formed to extend from the paper storage unit 5 to the in-body discharge unit 16. In the paper transport unit 13, a registration roller pair 12, a transport roller (not shown), and a discharge roller pair 15 are disposed. The paper in the paper storage unit 5 is carried into the paper transport unit 13 by the registration roller pair 12, and then the paper is transported in the order of the image forming unit 4, the fixing device 14, and the in-body discharge unit 16.

  The in-body discharge unit 16 is a part on which the image-formed paper is discharged and stacked by the discharge roller pair 15. The in-body discharge unit 16 is formed below the document reading unit 2 and above the image forming unit 4 at a position where a part of the main body 3 is opened. The in-body discharge unit 16 is formed so as to be accommodated inside the main body 3 when the multifunction machine 1 is viewed in plan. In the in-cylinder discharge unit 16, there is no barrier such as a panel on the other side surface other than the side surface on which the discharge roller pair 15 is arranged, and the user can take out the paper by inserting his hand through the opening. Further, the bottom of the in-body discharge unit 16 is inclined so as to gradually increase from the discharge roller pair 15 side toward the sheet discharge direction. Accordingly, the rear end portions of the sheets discharged to the in-body discharge portion 16 are aligned on the discharge roller pair 15 side.

  The temperature detection unit 17 is for detecting the ambient temperature of the discharge space H of the in-cylinder discharge unit 16 and includes, for example, a thermistor. This temperature detection part 17 should just be arrange | positioned in the part which can detect the atmospheric temperature of the discharge space H accurately. In the present embodiment, a range of the in-cylinder discharge unit 16 that is a lower part of the document reading unit 2 and faces the in-cylinder discharge unit 16 and on which frequently used paper, for example, A4 size paper is stacked. It is arranged at a position corresponding to the inside.

  The cooling unit 18 cools the discharge space H of the in-body discharge unit 16. The cooling unit 18 includes a cooling fan 181, a duct 182, a discharge port 183, and a ventilation port 184. The cooling fan 181 is attached in the main body 3 via an attachment member (not shown). The cooling fan 181 is rotatably supported in the attachment member. The cooling fan 181 is rotationally driven under the control of the control unit 19 to be described later, sucks outside air from a ventilation port 184 provided in the outer frame cover of the main body 3, and cools the cooled air through the duct 182 and the discharge port 183. Send to the inner discharge unit 16 side. The discharge port 183 is provided in the vicinity of the discharge roller pair 15 and is disposed at a position where the cooling air from the cooling fan 181 can be sent out in the direction in which the sheet is discharged.

  The control unit 19 includes a CPU, a RAM, and a ROM, and is electrically connected to the temperature detection unit 17 and the cooling fan 181 of the cooling unit 18. Then, the rotational drive of the cooling fan 181 of the cooling unit 18 is controlled according to the atmospheric temperature of the discharge space H of the in-body discharge unit 16 detected by the temperature detection unit 17. The control unit 19 compares the predetermined temperature stored in the ROM in advance with the atmospheric temperature detected by the temperature detection unit 17, and starts rotating the cooling fan 181 when determining that the atmospheric temperature is higher than the predetermined temperature, for example. When it is determined that the ambient temperature is lower than the predetermined temperature, control is performed such that the cooling fan 181 is not driven or stopped.

  In the copying machine 1 having such a configuration, the paper fixed by the fixing device 14 is discharged from the discharge roller pair 15 to the in-body discharge portion 16 in a state of being heated to high temperature by the fixing roller 141. Here, since the in-cylinder discharge unit 16 is provided in the lower part of the document reading unit 2 and in the upper part of the image forming unit 4 as described above, the heat of the sheets discharged and stacked in the in-cylinder discharge unit 16 is dissipated. Hateful. Then, the following two problems may arise.

  First, the toner on the paper stacked on the in-body discharge section 16 is in a state close to the melting point, and the toner on the overlapping paper is fused.

  Secondly, the heat of the sheets discharged and stacked on the in-cylinder discharge unit 16 rises, and the temperature of the document reading unit 2 disposed on the upper part of the in-cylinder discharge unit 16 is increased. Accordingly, there arises a problem that the reading accuracy of the document reading unit 2 is lowered and the function of the electrical component is lowered.

  In the present embodiment, a temperature detection unit 17 that detects the atmospheric temperature of the discharge space H of the in-body discharge unit 16 is provided, and the control unit 19 controls the cooling fan of the cooling unit 18 according to the atmospheric temperature detected by the temperature detection unit 17. By causing 181 to rotate and cool the discharge space H, the occurrence of these two problems is suppressed. Hereinafter, the cooling operation will be described in detail.

[Cooling operation]
The cooling operation of the discharge space H of the in-body discharge unit 16 will be described with reference to FIG. FIG. 2 is a flowchart showing control of the cooling fan 181 by the control unit 19.

  The rotational driving of the cooling fan 181 is controlled by the electrically connected control unit 19. Specifically, the control unit 19 compares the atmospheric temperature of the discharge space H detected by the temperature detection unit 17 with a predetermined temperature stored in advance in the ROM, and the atmospheric temperature is the same as or higher or lower than the predetermined temperature. Is determined (step S1). Here, the predetermined temperature is a dangerous temperature set according to the heat-resistant temperature of the document reading unit 2. When it is determined that the detected ambient temperature is the same as or higher than the dangerous temperature, the control unit 19 rotates the cooling fan 181 (step S2). The rotationally driven cooling fan 181 sucks outside air from the ventilation port 184 and sends out the cooled air to the in-body discharge unit 16 side through the duct 182 and the discharge port 183. Here, the discharge port 183 provided in the vicinity of the discharge roller pair 15 sends the cooling air from the cooling fan 181 in the paper discharge direction. Therefore, the flow of the cooling air sent out from the discharge port 183 takes a path passing through the discharge space H. Therefore, the discharge space H can be cooled, and the heat in the discharge space H can be discharged out of the main body 3.

  Even after the cooling fan 181 is rotationally driven, the control unit 19 compares the ambient temperature of the discharge space H detected by the temperature detection unit 17 with the dangerous temperature (step S3). Here, when it is determined that the ambient temperature of the discharge space H has become lower than the dangerous temperature due to cooling, the control unit 19 stops the rotational driving of the cooling fan 181 (step S4). On the other hand, when the atmospheric temperature of the discharge space H is still higher than the dangerous temperature, the blowing to the discharge space H of the in-body discharge portion 16 is continued until the atmospheric temperature becomes lower than the predetermined dangerous temperature.

  In the present embodiment, an example in which the control unit 19 drives or stops driving the cooling fan 181 according to the atmospheric temperature of the discharge space H of the in-body discharge unit 16 has been described. However, it is only necessary that the discharge space H can be cooled according to the atmospheric temperature of the discharge space H of the in-body discharge unit 16, and the control method of the cooling fan 181 by the control unit 19 is not limited to this. For example, when the cooling fan 181 is continuously driven during the operation of the copying machine 1 and it is determined that the ambient temperature of the discharge space H of the in-cylinder discharge unit 16 is higher than a predetermined temperature, the cooling fan 181 The rotational drive speed may be controlled to be further increased.

  Further, the timing of stopping the driving of the cooling unit 18 by the control unit 19 is not limited to this example. For example, the cooling fan 181 may be controlled to stop rotating after a predetermined time has elapsed from the start of driving of the cooling fan 181.

  Thus, in this embodiment, the temperature detection part 17, the cooling fan 181 and the control part 19 are provided. Then, according to the atmospheric temperature of the discharge space H of the in-cylinder discharge unit 16 detected by the temperature detection unit 17, the control unit 19 controls the driving of the cooling fan 181 to cool the discharge space H of the in-cylinder discharge unit 16. . Therefore, it is possible to cool the paper discharged to the in-cylinder discharge unit 16 and cool the document reading unit 2 disposed on the in-cylinder discharge unit 16. As described above, in the present embodiment, toner fusion between sheets can be prevented, and a temperature increase of the document reading unit can be avoided to prevent a decrease in the function of the document reading apparatus that can be caused by the temperature increase.

2. Second Embodiment The second embodiment has a configuration similar to that of the first embodiment except that a cooling unit is provided in the lower part of the document reading unit.

  With reference to FIG. 3, the cooling part 28 in 2nd Embodiment is demonstrated. In addition, about the structure similar to 1st Embodiment, the same code | symbol as 1st Embodiment is used.

  FIG. 3 is a sectional view of the copying machine 1 according to the second embodiment. The cooling unit 28 according to the second embodiment is disposed at a position below the document reading unit 2 and facing the in-body discharge unit 16. The cooling unit 28 includes a cooling fan 281 and is attached to the document reading unit 2 via an attachment member 282 provided with an air intake (not shown). The cooling fan 281 is rotatably supported in the mounting member.

  The cooling operation by the cooling unit 28 is the same as that in the first embodiment. That is, the control unit 19 controls the rotation of the cooling fan 281 according to the atmospheric temperature of the discharge space H detected by the temperature detection unit 17. For example, when it is determined that the ambient temperature is the same as or higher than the dangerous temperature compared with a predetermined dangerous temperature stored in advance in the ROM, the control unit 19 rotates the cooling fan 281. The cooling fan 281 in a rotationally driven state sucks outside air from the air intake and cools the discharge space H by sending cooling air to the in-body discharge portion 16 side. Further, when the control unit 19 determines that the atmospheric temperature of the discharge space H is lower than the dangerous temperature, the control unit 19 performs control so that the cooling fan 281 is not rotationally driven or stopped.

  Thus, in this embodiment, the temperature detection part 17, the cooling fan 281 and the control part 19 are provided. Then, according to the atmospheric temperature of the discharge space H of the in-cylinder discharge unit 16, the control unit 19 controls the driving of the cooling fan 281 to cool the discharge space H of the in-cylinder discharge unit 16. Therefore, it is possible to cool the paper discharged to the in-cylinder discharge unit 16 and cool the document reading unit 2 disposed on the in-cylinder discharge unit 16. From the above, in this embodiment, not only the toner fusion between sheets can be prevented, but also the temperature increase of the document reading unit 2 can be avoided and the deterioration of the function of the document reading apparatus that can be caused by the temperature increase can be prevented.

3. Third Embodiment In the third embodiment, the control unit controls the driving of the cooling fan according to the atmospheric temperature of the discharge space of the in-cylinder discharge unit detected by the temperature detection unit, and further the fixing temperature of the fixing device. To control. Other than that, it has the same configuration as that of the first embodiment, and hereinafter, the third embodiment will be described using the same reference numerals as those of the first embodiment.

  In the third embodiment, the control unit 19 is further electrically connected to a heat source (not shown) such as a halogen lamp built in the fixing roller 141. Then, the driving of the heat source of the fixing roller 141 is controlled according to the ambient temperature of the discharge space H of the in-body discharge unit 16 detected by the temperature detection unit 17. For example, when the control unit 19 determines that the ambient temperature is equal to or higher than a predetermined dangerous temperature stored in advance in the ROM, the control unit 19 rotates the cooling fan 181 and drives the heat source of the fixing roller 141 so as to lower the fixing temperature. To control. Here, the fixing temperature is changed within a range where no fixing failure occurs.

  After that, when the control unit 19 determines that the atmospheric temperature in the discharge space H of the in-cylinder discharge unit 16 is lower than a predetermined dangerous temperature, the control unit 19 stops the rotation driving of the cooling fan 181 and sets the fixing temperature to the originally set temperature. The drive of the heat source of the fixing roller 141 is controlled to return.

  As described above, in the present embodiment, the control unit 19 controls the driving of the cooling fan 181 according to the atmospheric temperature of the discharge space H of the in-cylinder discharge unit 16 detected by the temperature detection unit 17, and further the fixing device. 14 fixing temperature is controlled. Therefore, not only the discharge space H can be cooled, but also the paper whose temperature has already decreased can be discharged to the in-body discharge unit 16. Accordingly, it is possible to more efficiently prevent toner fusion between sheets and prevent deterioration of the function due to the temperature increase of the document reading unit 2.

4). Fourth Embodiment In the fourth embodiment, the control unit controls the driving of the cooling unit according to the atmospheric temperature of the discharge space of the in-cylinder discharge unit detected by the temperature detection unit, and further, the sheet in the image forming apparatus. Control the number of processed sheets. Other than that, it has the same configuration as the first embodiment, and hereinafter, the fourth embodiment will be described using the same reference numerals as the first embodiment.

  In the fourth embodiment, the control unit 19 is further electrically connected to the image forming unit 4 and the registration roller pair 12. Then, according to the atmospheric temperature in the discharge space H of the in-cylinder discharge unit 16 detected by the temperature detection unit 17, the control unit 19 controls the driving of the cooling fan 181 and the photosensitive drum 6 in the image forming unit 4. The image forming speed such as the rotation speed of the image forming apparatus and the rotation speed of the registration roller pair 12 are controlled. Specifically, when the control unit 19 determines that the ambient temperature is equal to or higher than a predetermined dangerous temperature stored in advance in the ROM, the control unit 19 starts to rotate the cooling fan 181 to drive the cooling fan 181 and to rotate the image. The formation speed and the rotation speed of the registration roller pair 12 are controlled to be slow. Then, the speed at which the toner image is formed in the image forming unit 4 is slowed down, and the carry-in interval of the paper carried into the image forming unit 4 from the registration roller pair 12 through the paper carrying unit 13 and finally in the cylinder The discharge interval of the paper discharged to the discharge unit 16 is increased. As described above, when the discharge interval of the paper discharged to the in-body discharge unit 16 is increased, the diffusion of heat is promoted as compared to when the discharge interval is narrow. Therefore, toner fusion between sheets can be prevented.

  Thereafter, when the control unit 19 determines that the atmospheric temperature in the discharge space H of the in-cylinder discharge unit 16 is lower than a predetermined temperature, the control unit 19 stops the rotation drive of the cooling fan 181 and also rotates the image forming speed and the registration roller pair 12. Control the speed back to the original speed.

Thus, in this embodiment, the control unit controls the driving of the cooling fan and further controls the number of sheets processed in the image forming apparatus. Therefore, first, the temperature of the sheet discharged to the in-body discharge unit 16 can be lowered. Further, by simultaneously cooling the discharge space H of the in-body discharge unit 16 by the cooling unit 18, it is possible to more efficiently prevent toner fusion between sheets and prevent deterioration of the function due to the temperature rise of the document reading unit. [Other Embodiments]
(a) The application of the temperature detection unit, the cooling unit, and the control unit of the present invention is not limited to a copying machine, and can be similarly applied to other image forming apparatuses.

  (b) The shape and the number of cooling units and cooling fans are not limited to the above-described embodiment, and various modifications are possible as long as the discharge space of the in-cylinder discharge unit can be cooled.

  (c) The predetermined temperature stored in the ROM of the control unit is not limited to the dangerous temperature set according to the heat-resistant temperature of the document reading unit, and may be another temperature. For example, the temperature at which the toner on the paper is fused may be set as the predetermined temperature.

  (d) A plurality of predetermined temperatures may be stored in advance in the ROM of the control unit. For example, the above-mentioned dangerous temperature and toner fusing temperature may be set and stored as the predetermined temperature if the toner fusing temperature is lower than the dangerous temperature.

  Here, the cooling fan may be set so that it can be driven in two stages of medium speed and high speed. For example, when the ambient temperature of the discharge space is higher than the toner fusing temperature but lower than the dangerous temperature, the control unit drives the cooling fan at a medium speed, and when the ambient temperature becomes higher than the dangerous temperature, It may be driven by.

  Furthermore, when the atmospheric temperature of the discharge space is higher than the toner fusing temperature but lower than the dangerous temperature, the control unit controls the fixing temperature of the fixing device and the number of sheets processed, and the atmospheric temperature is higher than the dangerous temperature. After the determination, the control of the rotational drive of the cooling fan may be started for the first time.

  As described above, embodiments obtained by appropriately combining the embodiments described in different columns are also included in the technical scope of the present invention.

1 is a schematic sectional view of a copying machine according to a first embodiment of the present invention. A flow chart of cooling fan control by the control unit. FIG. 6 is a schematic sectional view of a copying machine according to a second embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copier 2 Original reading part 3 Main body 4 Image forming part 5 Paper storage part 12 Registration roller pair 14 Fixing device 15 Discharge roller pair 16 In-cylinder discharge part 17 Temperature detection part 18 28 Cooling part 181 282 Cooling fan 183 Discharge port 19 Control Part H Discharge space

Claims (7)

A main body, a document reading unit that reads image information, an image forming unit that forms an image on a sheet based on the image information of the document read by the document reading unit, and fixing an unfixed image formed on the sheet by heating A fixing unit for holding paper, a paper storage unit for storing paper to be supplied to the image forming unit, a lower part of the original reading unit and an upper part of the image forming unit, and is opened in the main body for taking out paper. A cooling device that is provided in an image forming apparatus including an in-cylinder discharge unit that discharges a sheet on which an image is recorded, and cools a discharge space of the in-cylinder discharge unit,
A temperature detection unit for detecting the ambient temperature of the discharge space of the in-cylinder discharge unit;
A cooling section for cooling the discharge space;
A controller that drives the cooling unit according to the ambient temperature;
A cooling apparatus for an image forming apparatus.   The cooling device for an image forming apparatus according to claim 1, wherein the cooling unit includes a cooling fan.   The cooling device for an image forming apparatus according to claim 1, wherein the cooling unit is disposed in the main body, and cooling air from the cooling unit is sent along a discharge direction of the sheet to the in-cylinder discharge unit. .   The cooling device for an image forming apparatus according to claim 1, wherein the cooling unit is disposed at a position that is a lower part of the document reading unit and faces the in-body discharge unit.   5. The cooling device for an image forming apparatus according to claim 1, wherein the control unit further controls a fixing temperature in the fixing unit according to the ambient temperature.   The cooling device for an image forming apparatus according to claim 1, wherein the control unit further controls a sheet processing speed in accordance with the ambient temperature. The body,
A document reading section for reading image information;
An image forming unit that forms an image on a sheet based on image information of the document read by the document reading unit;
A fixing unit for fixing an unfixed image formed on a sheet by heating;
A paper storage unit for storing paper to be supplied to the image forming unit;
An in-cylinder discharge unit that is located at a lower part of the document reading unit and at an upper part of the image forming unit, is opened for taking out a sheet in the main body, and discharges a sheet on which an image is recorded;
The cooling device according to any one of claims 1 to 6,
An image forming apparatus comprising:

Images