JPH07234624A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To provide an electrophotographic device equipped with an image erasing device which is made compact and inexpensive and contrived to save a space in an office by integrally assembling an image erasing device in an electrophotographic device. CONSTITUTION:This device is provided with the image erasing device equipped with a printed paper housing means 32, a printed paper supplying means 33, a wetting means 34 wetting toner on the surface of printed paper 31, a toner peeling means 35 obtaining recycled paper 50 where erasion has been performed by heating the paper 31 after wetting and peeling the toner stuck to the surface of the paper, and a drying means 36 drying the recycled paper 50 wetted after peeling the toner; and the drying means 36 and a fixing means in the image erasing device are integrally formed as a common fixing and drying unit 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus having an image erasing device.

[0002]

6 and 7 show an example of a conventional electrophotographic apparatus. FIG. 6 shows a digital copying machine and FIG. 7 shows a laser printer. 6 and 7, the apparatus main body 1 includes a paper feed tray 3 as a print paper storage means for storing the print paper 2, and a print paper supply means for feeding the stored print paper 2. A sheet feeding unit 4, a photoconductor 5 as a latent image carrier, a latent image forming unit 6 as a latent image forming means for forming a latent image on the photoconductor 5, and a latent image formed by the toner. The image forming unit 7 as a visualizing means that visualizes the image by the image forming unit 7 and a transfer means that transfers the visualized visible image on the photoconductor 5 to the printing paper 2 to form a printed paper 31. The transfer unit 8 is roughly divided into a fixing unit 9 as a fixing unit that heats and fixes the toner attached to the printed paper 31.

In this case, the printing paper feeding unit 4 comprises a feeding roller 10, a feeding roller 12 arranged in a feeding path 11, a registration roller 13 and the like. The latent image forming unit 6 includes a light source unit (not shown) that emits laser light, a polygon mirror 14, a lens 15, a mirror 16, and the like. A scanner unit 17 is provided above the latent image forming unit 6 shown in FIG.
7 is a lamp 18, a plurality of mirrors 19, a lens 20, a CC
It consists of D21. Further, the image forming unit 7 is
A developing unit 22, a charging unit 23, a cleaning unit 24 and the like are arranged around the photoconductor 5. A transfer unit 8, a separation unit 25, and a conveyance unit 26 are arranged below the photoconductor 5. further,
The fixing unit 9 is arranged on the downstream side of the transport unit 26. The fixing unit 9 includes a fixing roller 2
7 and the pressure roller 28 are arranged in pressure contact with each other. On the downstream side of the fixing unit 9, a paper discharge tray 29 is provided outside the apparatus main body 1. As a result, the print paper 2 fed from the paper feed tray 3 is
An image is transferred by the transfer unit 8 below the photoconductor 5 and is fixed in the fixing unit 9 to be discharged as a printed paper 31 on the paper discharge tray 29. Image creation processing is performed by such a series of operations.

In recent years, there is an increasing demand for an image erasing apparatus that erases and reproduces printed paper (copied paper) inside the office without taking confidential documents and the like out of the office. An example of the image erasing device will be described with reference to FIG. The apparatus main body 30 has a printed paper feed tray 32 (hereinafter, referred to as a paper feed tray 32) as a printed paper storage means that stores a printed paper 31 with a part thereof protruding to the side surface of the main body.
And a printed paper feeding unit 33 (hereinafter, referred to as a paper feeding unit 33) as a printed paper feeding means for feeding the printed paper 31 stored in the paper feeding tray 32, and A wetting unit 34 as wetting means for wetting the surface of the toner of the printed printed sheet 31.
A toner peeling unit 35 as a toner peeling unit that heats the wet printed paper 31 to peel off the toner adhering to the paper surface, and a wet printed paper 31 after the toner is peeled off is dried. Erased recycled paper 5
It is roughly divided into a drying unit 36 as a drying means for setting to 0.

In this case, in the paper feeding unit 33,
A paper feed roller 37 for feeding the printed paper 31 in the paper feed tray 32, a conveyance path 38, a conveyance roller 39, and the like are provided. In the wetting unit 34, the treatment liquid 4
0, a coating roller 41, a conveyance roller 42, etc. are provided. In the toner peeling unit 35, a pair of toner peeling rollers 44 having a heater 43 built-in, separation claws 45 in contact with these toner peeling rollers 44, and cleaning roller 4 are provided.
6 and the like are provided. In the drying unit 36, a drying roller 48 having a heater 47 built therein, and the drying roller 4
A pressure roller 49 and the like that are in contact with 8 are provided. A discharge tray 51 for storing the erased recycled paper 50 formed by drying the printed paper 31 is provided outside the main body on the downstream side of the drying unit 36. As a result, the printed paper 31 is first wetted in the wet unit 34, and then the toner on the paper surface is erased in the toner peeling unit 35. Further, the printed paper 31 in which the toner has been erased and is in a wet state is dried in the drying unit 36, and is discharged onto the paper discharge tray 51 as erased recycled paper 50. The image erasing process is performed by such a series of operations.

[0006]

In recent years, in offices, in addition to the digital copying machine (see FIG. 6) and the laser printer (see FIG. 7) described above, many office automation equipment such as facsimiles and personal computers have been installed. The current situation is that they are narrowly installed. At the same time, from the aspect of resource conservation by maintaining confidentiality and recycling, the demand for the image erasing device (see FIG. 8) as described above for erasing and reproducing confidential documents and general printed paper inside the office has further increased. And, in the future, it is becoming a necessity item in the office. However, if such an image erasing device is to be provided in an office, it must be installed side by side with another OA device such as a copying machine or a printer, and a space for installing the image erasing device is newly required. Become. As described above, at the present stage, the electrophotographic apparatus such as a copying machine and the image erasing apparatus have to be separately installed, so that there is a problem that the space of the office becomes small. It is not economical to install it in.

[0007]

According to a first aspect of the present invention, there is provided a print sheet storing means for storing print sheets, a print sheet feeding means for feeding the stored print sheets, and a latent image carrier. A latent image forming means for forming a latent image on the latent image carrier, a visualization means for developing the formed latent image with toner, and the visualized latent image carrier In the electrophotographic apparatus including a transfer unit that transfers the visible image of the above to the printing paper to form a printed paper, and a fixing unit that heats and fixes the toner adhering to the printed paper, the printed paper is Printed paper storing means for storing, printed paper feeding means for feeding the stored printed paper, wetting means for wetting the toner on the surface of the fed printed paper, and after the wetting The printed paper of is heated and attached to the surface of the paper. The image erasing device is provided with a toner peeling means for peeling the removed toner to obtain erased recycled paper, and a drying means for drying the wet erased recycled paper after the toner is peeled off. The drying means and the fixing means in the apparatus are integrally formed as a common fixing / drying unit.

According to a second aspect of the present invention, in the first aspect of the invention, the heat supply amount to the erased recycled paper conveyed during drying in the fixing / drying unit is the heat supply to the printing paper conveyed during fixing. A means for changing the amount of heat supply during fixing and drying is provided to increase the amount of heat supplied.

According to the invention of claim 3, claim 1 or 2
In the invention described above, a paper conveyance destination switching means for switching the conveyance destination of the paper is provided on the downstream side of the fixing / drying unit to which the printed paper or the erased recycled paper is conveyed, and the paper conveyance destination switching means is provided on the downstream side of the paper conveyance destination switching means. A printed paper discharge means for discharging printed paper and an erased recycled paper discharge means for discharging erased recycled paper are formed separately from each other.

[0010]

According to the first aspect of the present invention, the image erasing device is incorporated and integrated in the electrophotographic device such as a copying machine or a printer, and further, the fixing device on the electrophotographic device side and the drying device on the image erasing device side. By forming and as a common fixing / drying unit, it is possible to combine the copying function and the image erasing function in one device, so that it is possible to obtain a low-cost composite device in which the number of parts is further reduced. It will be possible. Further, as a result, it is not necessary to separately install the electrophotographic apparatus and the image erasing apparatus in the office as in the conventional case, and it is possible to reduce the space in the office.

According to the second aspect of the present invention, in the fixing / drying unit, the heat supply amount supplied to the erased recycled paper at the time of drying and the heat supply amount supplied to the printing paper at the time of fixing are made different. Therefore, it is possible to eliminate waste of electric energy and perform the fixing process and the drying process in the best condition.

According to the third aspect of the present invention, the fixed printed sheet discharged from the fixing / drying unit is guided to the printed sheet discharging means, and the dried recycled sheet is discharged to the erased recycled sheet. Since the sheets are discharged to separate places by being guided to the means, it is possible to eliminate the mixture of the printed sheets and the erased recycled sheets on the tray after the sheet discharge is completed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention described in claim 1 will be described with reference to FIGS. Prior art (FIGS. 6 to 8)
The description of the same parts as those of is omitted, and the same reference numerals are used for the same parts. First, as a first embodiment of an electrophotographic apparatus having an image erasing device, a digital copying machine as shown in FIG. 1 will be taken as an example. This digital copying machine is one in which the image erasing device as shown in FIG. 8 is incorporated in the inside of the digital copying machine as shown in FIG. Hereinafter, description of the digital copying machine will be omitted, and only the image erasing device will be described. First, in the lower part of the apparatus main body 1, a paper feed tray 32 is arranged as a printed paper storage means for storing the printed paper 31. A paper feed roller 37 is provided above the paper feed tray 32.
A printed paper feed unit 33 is provided as a printed paper feed means including a transport path 38 and a transport roller 39. A wetting unit 34 as a wetting unit for wetting the surface of the toner of the fed printed paper 31 is arranged in the middle of the transport path 38. The wetting unit 34 includes a processing liquid 40 contained in a wetting tank 52 and a nozzle 53. In the conveying path 38 above the wetting unit 34, a toner stripping unit as a toner stripping unit that heats the printed sheet 31 after wetting to strip the toner adhering to the surface of the sheet to make the erased recycled sheet 50. 35 are provided. The toner peeling unit 35 includes the heater 4
3 includes a toner peeling roller 44 and a roller 54 in contact with the toner peeling roller 44. Above the toner peeling unit 35, a drying unit 36 is arranged as a drying unit for drying the wet erased recycled paper 50 after being peeled off. The drying unit 36 includes a drying roller 48 having a heater 47 built-in, and a pressure roller 49 that comes into pressure contact with the drying roller 48. On the outer side surface of the apparatus main body 1 on the downstream side of the drying unit 36, a paper discharge tray 51 for storing the discharged paper is provided. Further, the drying roller 48 in this embodiment also has a function as a fixing roller (fixing roller 27 in FIG. 6) of the digital copying machine. Therefore, hereinafter, the drying roller 48 will be referred to as the fixing / drying roller 48, and accordingly, the drying unit 36 will be referred to as the fixing / drying unit 36.

In such a structure, first, the printed paper 31 which has been printed by the digital copying machine and which is to be printed and whose image is to be erased is put in the paper feed tray 32 with its printing surface facing upward. The printed paper 31 fed from the paper feed tray 32 is coated with the treatment liquid 40 ejected from the nozzle 53. After this application, the printed paper 31 is heated and pressed by the toner peeling roller 44 to remove the toner adhering to the paper surface. The printed paper 31 after the toner removal is referred to as erased recycled paper 50. The toner attached to the toner peeling roller 44 side is peeled off by the scraper 55. Next, the erased recycled paper 50 still wet with the processing liquid 40 after the peeling.
Is introduced into the fixing / drying unit 36 and heated and dried by the fixing / drying roller 48. After that, the erased recycled paper 50 discharged from the fixing / drying unit 36
Are stored on the discharge tray 51. Although the paper feeding type in the digital copying machine of the present embodiment is a front loading type, a small-sized paper (for example, A
Only the size of up to 4 portraits) can be set.

Next, a second embodiment will be described by taking a laser printer as shown in FIG. 2 as an example. This laser printer is an example in which the image erasing device as shown in FIG. 8 is incorporated and integrated with the laser printer as shown in FIG. Here, the paper feed tray 32 is set on the outer side surface of the apparatus main body 1. Further, the wetting unit 34 is not of a nozzle type but of a contact type using the coating roller 41. Further, the pressure roller 49 in the fixing / drying unit 36 has a heater 56 built therein.

In such a configuration, the printed surface of the printed paper 31 on which the image has been printed and whose image is to be erased is placed in the paper feed tray 32 with the printing surface facing downward. Then, the printed sheet 31 fed and fed is applied to the application roller 4 to which the treatment liquid 40 is applied.
Passes in contact with 1. After this application, printed paper 31
Is heated and pressed by the toner peeling roller 44 to remove the toner on the printed paper 31. The removed printed paper 31 is referred to as erased recycled paper 50. The toner attached on the toner peeling roller 44 is peeled off by the scraper 55. Next, the erased recycled paper 50 still wet with the processing liquid 40 after the peeling is introduced into the fixing / drying unit 36 and heated and dried by the fixing / drying roller 48. The erased recycled paper 50 discharged from the fixing / drying unit 36 is stored on the paper discharge tray 51.

In this case, the printing surface by the laser printer is the upper surface side of the printing paper 2 to be set, and the erasing surface (wetting surface) by the image erasing device is the printed paper 3 to be set.
1 is the lower surface side (that is, the direction opposite to that at the time of printing). As described above, since the surface to be heated in the fixing / drying unit 36 is different between fixing and drying, the pressure roller 4 is used in this embodiment.
A heater 56 is also provided inside 9. Table 1 shows the heater 4
7 shows a state of heating control of Nos. 7 and 56. The heater 47 on the fixing / drying roller 48 side is turned on at the time of fixing, and the heater 56 on the pressure roller 49 side is turned on at the time of drying.
Accordingly, even if the fixing surface and the drying surface are different in the same unit, the fixing / drying processing can be performed without any problem.

[0018]

[Table 1]

As described above, by incorporating the image erasing device into the digital copying machine and integrating them, the size of the device can be reduced, and further, the fixing means on the electrophotographic device side and the drying on the image erasing device side. By forming the fixing / drying unit 36 in common with the means, the number of parts in the apparatus can be further reduced. Therefore, as described above, it is not necessary to separately install the electrophotographic apparatus and the image erasing apparatus in the office as in the conventional case, the space in the office can be reduced, and the size and size can be reduced. It is possible to provide an electrophotographic apparatus provided with a costly image erasing apparatus. In general, a laser printer or an image erasing apparatus cannot be used even when the power source of the apparatus main body is turned on until the fixing section or the drying section thereof is sufficiently warmed. However, by incorporating the heaters 47 and 56 in the fixing / drying roller 48 and the pressure roller 49 respectively as in the present embodiment, the heaters 47 and 56 are heated immediately after the power source of the apparatus main body side is turned on. Therefore, it is possible to shorten the time required for the fixing / drying unit 36 to warm up, which can further improve the work efficiency.

Next, an embodiment of the invention described in claim 2 will be described with reference to FIGS. 3 and 4. The description of the same parts as those in the first aspect of the present invention will be omitted, and the same reference numerals will be used for the same parts. In the case where the electrophotographic apparatus and the image erasing apparatus are integrally provided in the same apparatus and the fixing means and the drying means are made common to constitute one fixing / drying unit as in the above-mentioned invention of claim 1. It was found that the amount of heat required by the printing paper 2 during fixing and the amount of heat required by the erased recycled paper 50 during drying were different. According to the experimental results, the amount of heat required for drying was larger than the amount of heat required for fixing.
Therefore, if the amount of heat required for drying is set in advance as the condition for setting the amount of heat in the fixing / drying unit 36, both the fixing and drying steps can be satisfied. However, with such a method of setting the amount of heat, an unnecessary amount of heat is added during fixing, resulting in a waste of electric energy.

Therefore, in this embodiment, in the fixing / drying unit 36 of the electrophotographic apparatus equipped with the image erasing device according to the first aspect, the erased recycled paper 5 conveyed at the time of drying.
A fixing / drying heat supply amount changing means (not shown) for increasing the heat supply amount to 0 than the heat supply amount to the printing paper 2 conveyed at the time of fixing is provided. Hereinafter, specific examples of the fixing and drying heat supply amount changing means for changing the amount of heat applied to the paper will be sequentially described.

First, as the first specific example of the fixing / drying heat supply amount changing means for changing the amount of heat applied to the paper, the printing paper 2 and the erased recycled paper 50 are fixed / drying units 36.
There is a way to change the time it takes to pass through. To change the passage time, the speed of the fixing / drying roller 48 may be changed. Table 2 shows the degree of drying of the erased recycled paper 50 moistened with the processing liquid 40 by changing the speed of the fixing / drying roller 48 in the fixing / drying unit 36.
In this case, the speed of the fixing / drying roller 48 at the time of fixing is set as a reference value of 100%, and changes in the dry state when the speed is reduced to 50% are shown. From Table 2, it is desirable to set the speed of the fixing / drying roller 48 at the time of drying, which is slower than half the speed at the time of fixing.

[0023]

[Table 2]

From the above, as a first method for slowing the speed of the fixing / drying roller 48 at the time of drying,
There is a method of slowing the speed of a motor (not shown) which is a drive source. For example, printing unit A (digital copying machine side),
The erasing / drying unit B (on the image erasing device side) and the fixing / drying unit 36 are driven by separate motors, and only the speed of the motor driving the fixing / drying unit 36 is changed during printing and during drying. As a result, the amount of heat supplied to the erased recycled paper 50 conveyed during drying can be made larger than the amount of heat supplied to the printing paper 2 conveyed during fixing. By making the drive sources of the printing unit A and the erasing / drying unit B independent, noise can be reduced during printing and drying, and the life of the printing unit A and the erasing / drying unit B can be extended. . Further, as a second method of decreasing the speed of the fixing / drying roller 48, the drive output from the motor serving as a drive source is used for the printing section A, the erasing / drying section B, the fixing / drying unit
It is divided into 6 and 3 systems, and the printing section A and the erasing and drying section B are separated.
There is a method of interposing a clutch (not shown) so that drive transmission can be cut off and connected. in this case,
At the time of printing, the driving force is transmitted to the printing unit A and the fixing / drying unit 36, and is not transmitted to the erasing / drying unit B, and is cut off. On the contrary, at the time of drying, the driving force is transmitted to the erasing / drying unit B and the fixing / drying unit 36, the rotation speed of the motor is reduced, and the printing unit A is cut off without being transmitted. This allows
The amount of heat supplied to the erased recycled paper 50 conveyed during drying can be made larger than the amount of heat supplied to the printing paper 2 conveyed during fixing. It should be noted that the erasing and drying section B
However, since the printing unit A is not driven during drying, the printing unit A and the erasing / drying unit B can have a longer life, lower noise, lower torque of the motor, and cost reduction by reducing the number of motors. .

Next, as a second specific example of the fixing / drying heat supply amount changing means for changing the amount of heat applied to the paper, there is a method of changing the nip width between the fixing / drying roller 48 and the pressure roller 49. Generally, as the fixing / drying roller 48, a metal roller such as aluminum coated with a fluorine resin is often used, and as the pressure roller 49, a metal roller such as aluminum coated with silicon rubber is used. Many are used. In this case,
As shown in (a), the pressure shaft 57 of the pressure roller 49 is pressed by the pressure lever 58 so that the pressure roller 49 bites into the fixing / drying roller 48 to increase the nip width. In this embodiment, the pressing lever 58 is pressed by the eccentric cam 59, and when drying, as shown in FIG.
As compared with (a), the amount of the pressure roller 49 biting into the fixing / drying roller 48 is increased to widen the nip width. As a result, the amount of heat supplied to the erased recycled paper 50 conveyed during drying can be made larger than the amount of heat supplied to the printing paper 2 conveyed during fixing.

Next, as a third specific example of the fixing / drying heat supply amount changing means for changing the amount of heat applied to the paper, the heater 4 is used.
There is a method of changing the heat generation amount of 7,56. As shown in FIG. 4, two heaters 47, 60 are provided in the fixing / drying roller 48.
And one of the heaters 47 (or the heater 6 at the time of fixing).
0) is energized, and two heaters 47 and 6 are used during drying.
0 is energized together. In the concrete examples so far, all are shown in FIG.
In the case of the laser printer of FIG. 2, as shown in Table 3, only the fixing / drying roller 48 is turned on during fixing, and the fixing / drying roller 48 and pressure are applied during drying. Turn on both rollers 49. As a result, the amount of heat supplied to the erased recycled paper 50 conveyed during drying can be made larger than the amount of heat supplied to the printing paper 2 conveyed during fixing.

[0027]

[Table 3]

As described above, the fixing / drying unit 36
In the above, since the heat supply amount supplied to the erased recycled paper 50 at the time of drying is made different from the heat supply amount supplied to the print paper 2 at the time of fixing, it is possible to save waste of electric energy and save power. The fixing process and the drying process can be performed in the best condition, and the work efficiency can be improved.

Next, an embodiment of the invention described in claim 3 will be described with reference to FIG. The description of the same parts as those in the first and second aspects of the present invention is omitted, and the same parts are designated by the same reference numerals. Generally, when a facsimile or printer is used as the electrophotographic apparatus and the electrophotographic apparatus is equipped with the image erasing apparatus (see FIGS. 1 and 2) described above, printing is performed even when there is no operator such as at night. There are cases where For example, the erased recycled paper 50 after the image (toner) deletion is the paper output tray 51.
When it remains inside, a print command may be sent from a CPU (not shown), and the printed paper 31 may be discharged onto the paper discharge tray 51. This allows
Although the erased recycled paper 50 and the printed paper 31 are actually mixed on the paper discharge tray 51, the operator mistakenly outputs only the printed paper 31 on the paper discharge tray 51. There is a case where those papers are misunderstood and taken to a place away from the apparatus. On the contrary, the printed paper 3 after printing
When 1 remains in the discharge tray 51, the image erasing device may be activated to discharge the erased recycled paper 50 after the image is erased onto the printed paper 31. To be In any of these cases, the operator thinks that both papers are not mixed and only one of the papers (printed paper 31 or erased recycled paper 50) is ejected, and the paper is ejected at another place. It would be confusing in the office when doing the sorting work for distribution.

Therefore, in view of such a point, in the present embodiment, an electrophotographic apparatus provided with the image erasing apparatus according to the first and second aspects of the present invention (here, the digital copying machine of FIG. 1 is taken as an example. In (1), a paper conveyance destination switching means 61 for switching the conveyance destination of the paper is provided downstream of the fixing / drying unit 36 to which the printed paper 31 or the erased recycled paper 50 is conveyed, and the paper conveyance destination switching means 61. On the downstream side of which a printed paper discharge means 62 for discharging the printed paper 31 and an erased recycled paper discharge means 63 for discharging the erased recycled paper 50 are formed separately from each other. Is. In this case, the paper conveyance destination switching means 61 is
It is composed of a solenoid 64 and a switching lever 65. The printed paper ejecting means 62 includes a paper ejecting passage 66, a pair of paper ejecting rollers 67, and a paper ejecting tray 51a.
It consists of and. The erased recycled paper ejecting means 63 comprises a paper ejecting passage 68, a pair of paper ejecting rollers 69, and a paper ejecting tray 51b.

In such a configuration, for example, at the time of printing, the solenoid 64 is turned on, so that FIG.
As shown in (a), the switching lever 65 closes the lower paper discharge passage 68 and becomes parallel to the upper paper discharge passage 66. Therefore, the printed paper 31 is sent by the paper discharge rollers 67. The sheet is discharged to the sheet discharge tray 51a. On the contrary, at the time of drying, as shown in FIG. 5B, the solenoid 64 is turned off, and the switching lever 65 closes the upper paper discharge passage 66 to be parallel to the lower paper discharge passage 68. Therefore, the erased recycled paper 50 is sent by the paper discharge roller 69 and is discharged to the lower paper discharge tray 51b.

As described above, the printed paper 3 after printing
It is possible to prevent the printed sheet 31 and the erased recycled sheet 50 from being mixed by ejecting 1 to the sheet discharge tray 51a and the dried erased recycled sheet 50 to the sheet discharge tray 51b. As a result, the operator does not get confused during the paper sorting work, and the work efficiency can be further improved.

[0033]

According to the first aspect of the present invention, the printing paper storage means for storing the printing paper, the printing paper feeding means for feeding the printing paper stored therein, the latent image carrier, and the latent image are provided. A latent image forming means for forming a latent image on the carrier; a developing means for developing the formed latent image with toner; and a visualized image on the latent image carrier. An electrophotographic apparatus, comprising: a transfer unit that transfers the printed paper to a printed paper and a fixing unit that heats and fixes the toner adhering to the printed paper; Paper storing means, printed paper feeding means for feeding the stored printed paper, wetting means for wetting toner on the surface of the fed printed paper, and printed paper after the wetting To remove the toner adhering to the paper surface. The image erasing device is provided with a toner peeling means for forming an erased recycled paper sheet and a drying means for drying the wet erased recycled paper sheet after the toner is peeled off. Since the drying means and the fixing means are integrally formed as a common fixing / drying unit, the image erasing device is incorporated and integrated in the electrophotographic apparatus as described above. By forming the drying unit on the erasing device side as a common fixing / drying unit, it is possible to combine the copying function and the image erasing function in a single device, thereby reducing the number of parts and reducing the size and size. A cost-effective composite device can be provided. Further, this eliminates the need to separately install the electrophotographic apparatus and the image erasing apparatus in the office as in the conventional case, so that the space in the office can be further reduced.

According to a second aspect of the present invention, in the first aspect of the present invention, the heat supply amount to the erased recycled paper conveyed during drying in the fixing / drying unit is supplied to the printing paper conveyed during fixing. Since the fixing / drying heat supply amount changing means for increasing the fixing amount is provided, the waste of electric energy can be saved to save power, and the fixing process and the drying process can be performed in the best state.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a paper conveyance destination is provided to switch the conveyance destination of the paper to the downstream side of the fixing / drying unit to which the printed paper or the erased recycled paper is conveyed. Switching means is provided, and a printed paper discharge means for discharging the printed paper and an erased recycled paper discharge means for discharging the erased recycled paper are branched on the downstream side of the paper transport destination switching means. Since they are formed independently, it is possible to eliminate the mixture of printed paper and erased recycled paper on the tray after paper ejection is complete.
The operator will not be confused during the paper sorting work, and the work efficiency can be further improved.

[Brief description of drawings]

FIG. 1 is a view showing a configuration of an electrophotographic apparatus provided with an image erasing apparatus according to a first embodiment of the invention, and is a vertical sectional front view when a digital copying machine is used as the electrophotographic apparatus. Is.

FIG. 2 is a longitudinal sectional front view showing a configuration of an electrophotographic apparatus provided with an image erasing apparatus according to a second embodiment of the invention, wherein a laser printer is used as the electrophotographic apparatus. is there.

3A and 3B show an embodiment of the invention described in claim 2, wherein FIG. 3A is a front view showing a roller pressure contact state in a fixing / drying unit during fixing, and FIG. It is a front view which shows the roller pressure contact state in a drying unit.

FIG. 4 is a front view showing a configuration in which two heaters are provided on one roller in the fixing / drying unit.

5A and 5B are views showing an embodiment of the invention described in claim 3, wherein FIG. 5A is a front view showing a paper discharge state during fixing, and FIG. 5B is a front view showing a paper discharge state during drying. is there.

FIG. 6 shows a conventional example and is a vertical sectional front view when a digital copying machine is used as an electrophotographic apparatus.

FIG. 7 shows a conventional example and is a vertical sectional front view when a laser printer is used as an electrophotographic apparatus.

FIG. 8 is a vertical cross-sectional front view showing a configuration of an image erasing device, showing a conventional example.

[Explanation of symbols]

 2 printing paper 3 printing paper storage means 4 printing paper feeding means 5 latent image carrier 6 latent image forming means 7 visualization means 8 transfer means 9 fixing means (fixing / drying unit) 31 printed paper 32 printed paper storage Means 33 Printed paper feeding means 34 Wetting means 35 Toner peeling means 36 Drying means (fixing / drying unit) 50 Erased recycled paper 61 Paper transport destination switching means 62 Printed paper discharging means 63 Erased recycled paper discharging means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G03G 21/00 570

Claims (3)

[Claims] 1. A print sheet storage means for storing print sheets, a print sheet feeding means for feeding the stored print sheets, a latent image carrier, and a latent image formed on the latent image carrier. Latent image forming means, a latent image forming means for visualizing the formed latent image by toner, and the visualized image on the latent image carrier is transferred to the printing paper to print. In an electrophotographic apparatus provided with a transfer unit for forming a printed sheet and a fixing unit for heating and fixing the toner attached to the printed sheet, a printed sheet storing unit for storing the printed sheet and the stored unit Printed paper feeding means for feeding printed paper, wet means for wetting the toner on the surface of the printed paper fed, and heating the printed paper after wetting to adhere to the surface of the printed paper Removed toner and erased recycled paper And an image erasing device provided with a toner removing device for removing the toner and a drying device for drying the wet erased recycled paper after the toner is removed, and the drying device and the fixing device in the image erasing device. An electrophotographic apparatus characterized in that the above are integrally formed as a common fixing / drying unit. 2. A fixing / drying heat supply amount changing means for increasing the heat supply amount to the erased recycled paper conveyed during drying in the fixing / drying unit more than the heat supply amount to the printing paper conveyed during fixing. It is provided, The claim 1 characterized by the above-mentioned.
The described electrophotographic apparatus. 3. A paper transport destination switching means for switching the transport destination of the paper is provided on the downstream side of the fixing / drying unit to which the printed paper or the erased recycled paper is transported, and the paper transport destination switching means is provided on the downstream side. 3. A printed paper discharging means for discharging printed paper and an erased recycled paper discharging means for discharging erased recycled paper are formed separately from each other. Electrophotographic device.