JPH06138795A - Decoloring device and decoloring unit - Google Patents

Abstract

PURPOSE:To provide a decoloring device and a decoloring unit capable of efficiently decoloring a photochemically erasable toner, and short in the decoloring time per a paper short, light in weight and compact in size. CONSTITUTION:The decoloring device 1 is constituted of a pair of heating rollers consisting of a heating roller 10 and a pressure roller 11, a light source 12 such as a halogen lamp, reflection mirrors 13a and 13b, heat-resistant glass plates 14 and 15, paper feeding rollers 31 and 32 carrying a sheet body 2, carrying rollers 34, 35, 38 and 39, paper ejecting rollers 22 and 23, guiding members 33, 36, 37, 40, 41, 16 and 17, exhaust ducts 61, 65, 63 and 67, ventilation fans 62 and 66, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an erasing device and an erasing unit for erasing a photochemically erasable toner fixed on a sheet body.

[0002]

2. Description of the Related Art Recently, the reuse and recycling of used papers and plastics has been reviewed for the protection of global resources. However, regarding the reuse of recorded documents, an external recycling company should be consulted. Some requests have been made, but most of them are incinerated or crushed.

[0003]

In order to solve such a problem, the color of ink or toner fixed on the recording medium is erased while maintaining the shape of the recording medium.
Toner that can be reproduced as a plain recording medium,
It is proposed in Japanese Patent Application No. 3-277725. When electrostatic copying is performed using such a toner, a recorded image such as a copy sheet or the like recorded on a sheet or a recorded image such as a print can be erased by irradiating near infrared rays. Therefore, the recording medium can be easily reused.

However, there has been a problem that a decoloring device capable of decolorizing a photochemically decolorable toner efficiently and quickly has not been developed so far.

An object of the present invention is to provide a lightweight and compact erasing apparatus and erasing unit which can efficiently erase erasable photochemically erasable toner, and have a short erasing time per sheet. Is to provide.

[0006]

SUMMARY OF THE INVENTION The present invention is a heating means for heating a photochemically decolorizable toner fixed on a sheet member to at least the glass transition temperature of the binder resin of the toner. A light source for irradiating the toner with near infrared rays, and a light collecting means for collecting light from the light source to form a light collecting portion on the discharge side of the heating means. The erasing device is characterized in that exhaust ducts are provided above and / or below the sheet conveying path between the heating unit and the heating unit.

The present invention also provides a heating means for heating the photochemically decolorizable toner fixed on the sheet member to at least the glass transition temperature of the binder resin of the toner, and the heating means. The light source for irradiating near-infrared rays and the light collecting means for collecting the light from the light source to form a light collecting portion on the discharge side of the heating means are provided, and the light source and the light collecting means are integrated. The erasing device is characterized in that the light source unit included therein is relatively displaceable with respect to the heating means.

Further, according to the present invention, a heating means for heating the photochemically decolorizable toner fixed on the sheet body to at least the glass transition temperature of the binder resin of the toner, and the heating means. A light source for irradiating near-infrared rays, and a light collecting means for collecting light from the light source to form a light collecting portion on the discharge side of the heating means are provided. It is an erasing device characterized in that

The present invention also provides a heating means for heating the photochemically decolorizable toner fixed on the sheet member to at least the glass transition temperature of the binder resin of the toner, and the toner. A light source for irradiating near infrared rays, and a light collecting means for collecting light from the light source to form a light collecting portion on the discharge side of the heating means, and a supporting member for supporting the heating means are provided. The decoloring device is removable.

Further, according to the present invention, heating means for heating the photochemically decolorizable toner fixed on the sheet body to at least the glass transition temperature of the binder resin of the toner, and the heating means are provided. A light source for irradiating near-infrared rays, a light collecting means for collecting light from the light source to form a light collecting portion on the downstream side of the heating means for conveying the sheet body, the heating means, the light source, and the light source. An erasing unit, comprising: a box housing a light collecting means inside.

Further, according to the present invention, the box body has a bottom plate, two side plates standing upright on both sides of the bottom plate, a top plate connecting upper ends of the side plates, and a front plate having a carrying-in port for the sheet body. When,
It is characterized by comprising a light source housing member housing the light source and the light collecting means.

Further, the present invention is characterized in that the heating means can heat and fuse the unfixed toner on the sheet body and fix it on the sheet body.

The present invention is also characterized in that a discharge tray is detachably attached to the light source storage member.

[0014]

According to the present invention, a heating means for heating a photochemically decolorizable toner to a predetermined temperature, a light source for irradiating the toner with near infrared rays, and a light from the light source are used. Light collecting means for collecting and forming a light collecting portion on the discharge side of the heating means, and providing exhaust ducts above and / or below the sheet conveying path between the light source and the heating means, respectively. By this, the exhaust of the inside of the device is smoothly performed, and the rise of the internal temperature can be prevented. Further, it is possible to prevent the deformation of the sheet body due to the exhaust pressure difference on both sides of the sheet body, and suppress the so-called jam occurrence rate.

According to the invention, the light source unit integrally including the light source and the light condensing means is displaceable relative to the heating means, so that the sheet body is clogged on the discharge side of the heating means. When a so-called jam occurs, a large space is formed on the discharge side of the heating means by displacing the light source unit, which simplifies the jam removal work by the user.
Cleaning is extremely safe and easy.

Further, according to the present invention, in the case of erasing a sheet body having various erasing performances depending on the attached amount and the attached thickness of the fixed toner due to the variable conveying speed of the sheet body. For a sheet body that is easily erased, the erasing process time can be shortened by increasing the transport speed, and for a sheet body that is difficult to be erased, the heating amount and light The amount of irradiation is increased, and reliable decoloring processing can be performed. Therefore, it is possible to arbitrarily adjust which of the degree of residual decoloring remaining without being decolored and the decoloring processing time is prioritized in accordance with the user's request.

Further, according to the present invention, since the supporting member for supporting the heating means is detachable, when the heating means is replaced, the heating means can be taken out only by removing the supporting member. Maintenance such as repair, inspection and cleaning of the device can be performed easily and quickly.

Further, according to the present invention, there is provided a heating means for heating the photochemically decolorizable toner fixed on the sheet body to at least the glass transition temperature of the binder resin of the toner or more. By this, the thermal momentum of the molecules of the binder resin increases, the decolorization chemical reaction is promoted, and a light source for irradiating the thus heated toner with near-infrared rays, and the light from the light source are collected to heat the toner. By providing the light collecting means for forming light collection on the downstream side of the sheet body conveyance, the amount of light irradiation to the sheet body is increased, and the dye in the toner is efficiently decolorized. Also, heating means,
By providing the box body that houses the light source and the light condensing means, it is possible to eliminate the adverse effect of the heat discharged from these devices on the external device. Furthermore, the heating means, the light source, and the light collecting means are integrally housed inside the box, so that the relative position between them is fixed. Therefore, when the erasing unit according to the present invention is incorporated in another device, its assembling accuracy can be improved.

Further, the box body includes a bottom plate, two side plates standing on both sides of the bottom plate, a top plate connecting the upper ends of the side plates, a front plate having a sheet carrying-in port, a light source and a collector. Since it is possible to downsize the erasing unit and improve the space utilization efficiency by being configured with the light source housing member that houses the light means, it is easy to incorporate it in other equipment, and the equipment is small in size. It becomes possible.

Further, since the heating means can heat and fuse the unfixed toner on the sheet body and fix it on the sheet body, the erasing unit according to the present invention can also be used as a fixing device of an electrophotographic apparatus. Therefore, the electrophotographic apparatus having the erasing function can be realized in a lightweight and compact form.

Further, the paper discharge tray is detachably attached to the light source accommodating member, so that when the erasing unit according to the present invention is incorporated into another device, the erasing unit can be easily taken in and out. . Further, since the paper discharge tray can be removed even when the light source storage member is opened, maintenance workability is improved.

[0022]

EXAMPLES First, the toner used in the present invention will be described. The toner is a photochemically decolorizable toner, in particular, a decoloring toner that decolorizes by absorbing near-infrared rays, and examples of a large number of composition examples and other components constituting the toner such as a sensitizer, The details of the decoloring action of the toner of each composition example and the like are described in Japanese Patent Application No. 3-277725. Therefore, in the following examples, several examples of decolorizable toner will be shown. The present invention is not limited to the example of this embodiment, but includes a wide variety of modifications in accordance with the spirit of the present invention.

Such an erasable toner is, for example, constituted by dispersing a dye and an organic boron ammonium salt in a styrene resin. The dye is represented by, for example, the following (Chemical formula 1) or (Chemical formula 2).

[0024]

[Chemical 1]

[0025]

[Chemical 2]

The styrene resin is widely used as a binder resin for toner. The above (Chemical formula 1) and (Chemical formula 2)
The dye represented by is one of the cyanine dyes and has a wavelength of 820 when coexisted with an organic boron ammonium salt.
Irradiation with near-infrared rays in the vicinity of nm absorbs the near-infrared rays to cause an irreversible reaction, and the blue color disappears to become colorless. As the organic ammonium borate salt, for example, tetrabutylammonium n-butyltriphenylboron represented by the following (Chemical Formula 3) is used.

[0027]

[Chemical 3]

Next, the erasing device according to the present invention will be described. FIG. 1 is a front view showing the configuration of an erasing apparatus which is an embodiment of the present invention. The erasing device 1 includes a heating roller pair including a heat roller 10 and a pressure roller 11, a light source 12 such as a halogen lamp, reflecting mirrors 13a and 13b having concave surfaces, heat-resistant glass plates 14 and 15, and a paper sheet. Paper feeding rollers 31 and 32, conveying rollers 34, 35, 38 and 39, and discharging rollers 22 and 23 for conveying the sheet body 2 such as a plastic sheet, and a guide member 33 for smoothly guiding the sheet body 2, 36, 37, 40, 41, 1
6, 17 and exhaust ducts 61, 6 for discharging heat from the heating roller pairs 10, 11 and the light source 12 to the outside.
3, 65, 67 and exhaust fans 62, 66 and the like.

The sheet cassette 2 accommodates the sheet body 2 to which the photochemically decolorizable toner as described above is fixed. The sheet members 2 are taken out one by one by the sheet feeding rollers 31 and 32, and are guided along the one-dot chain line in the figure.
3, 36, 37, 40, 41 and conveyance rollers 34, 3
It is conveyed to the heating roller pair 10, 11 by 5, 38, 39.

The heat roller 10 is a hollow cylindrical roller made of metal or glass whose surface is coated with fluororesin or the like, and has a heater 10a such as a halogen lamp incorporated in the shaft center portion thereof. The current is applied to heat the surface to a predetermined temperature. The pressure roller 11 is a metal roller whose surface is thickly coated with silicon rubber. The pressure roller 11 is urged by a predetermined pressure against the heat roller 10 to move along the outer peripheral shape of the heat roller 10. The silicone rubber is elastically deformed to secure a predetermined contact area.

By passing the sheet body 2 while being sandwiched by the pair of heating rollers 10 and 11, the toner is heated above the glass transition temperature of the binder resin.

On the discharge side of the heating roller pair 10, 11, the light including the near infrared rays emitted from the light source 12 is reflected by the reflecting mirror 1.
3a, 13b, etc., form a condensing portion that is efficiently collected and has a high light irradiation density. Therefore, when the sheet body 2 is ejected from the heating roller pair 10 and 12, the near-infrared light is immediately irradiated, so that the color of the toner is efficiently erased. The decolored sheet body 2 is guided by the guide members 16 and 17, discharged to the outside by the discharge rollers 22 and 23, and placed on the discharge tray 42. The guide member 16 is composed of a plurality of linear members formed by bending such as wire, and is arranged at a predetermined interval along the conveying direction of the sheet body.

In this manner, the sheet body 2 once recorded with the toner is erased efficiently and quickly by the time the sheet body 2 is conveyed from the paper feed cassette 30 to the paper discharge tray 42.

The heating roller 10 and the pressure roller 11 of the heating roller pair are in contact with the cleaning rollers 20 and 21 impregnated with a releasing agent such as silicone oil. By moistening the surface with a release agent, the adhesion of the toner fixed on the sheet body 2 and the winding of the sheet body 2 are prevented. Also,
Separation claws 24 and 25 are in contact with the vicinity of the discharge side of the heat roller 10 and the pressure roller 11, respectively, and even when the sheet body 2 is in close contact with the heating roller pair 10 and 11, the tip ends of the separation claws 24 and 25. The sheet body 2 can be peeled off, and the sheet body 2 is prevented from being wrapped around.

At various points along the conveying path of the sheet body 2 (one-dot chain line in the figure), for example, the upper part of the guide member 36 and the paper discharge rollers 22,
Sheet body detection sensors 51 and 52 such as photocouplers and microswitches are installed on the discharge side of 23 as required to perform timing control and jam occurrence detection. In addition, at various places on the conveying path of the sheet body 2 and at various places of each roller, for example, the surface of the pressure roller 11 or the discharge roller 2
Static elimination brushes 56 and 57 are provided on the discharge sides of 2 and 23 to prevent the occurrence of electrostatic attraction of the sheet body 2.

A temperature sensor 53 such as a bimetal or thermistor is provided on the surface of the heat roller 10.
The temperature of the heat roller 10 is controlled. Further, a point where the temperature rises significantly, for example, the surface of the heat roller 10,
The reflecting mirror 13b and the guide member 17 have a thermal fuse 54,
55 and 56 are provided to prevent the occurrence of abnormally high temperature.

The heating roller pairs 10, 11 and the light source 12
Since a large amount of heat is generated in the vicinity of, the exhaust ducts 61 and 65 are installed on both sides of the conveyance path of the sheet body 2, and the exhaust fans 62 and 66 such as sirocco fans forcibly exhaust the exhaust ducts 63 and 67 and the ventilation. By releasing the gas through the ports 64 and 68 to the outside, the temperature rise in the device is prevented.

FIG. 2 is a cutaway side view showing a schematic structure of the erasing apparatus 1 of FIG. The heat roller 10, the pressure roller 11, and the cleaning rollers 20, 21 are rotatably supported with respect to the casing 6 and the auxiliary side plate 7, and the heater roller 10 has a heater such as a halogen lamp at its axis. 10a is provided. Therefore, when replacing each of the rollers 10, 11, 20, and 21, it is sufficient to remove only the auxiliary side plate 7 without disassembling the entire casing 6, and thus the maintenance workability is improved.

As shown in the central portion of the breakage in FIG. 2, the paper discharge rollers 22 and 23 are axially supported at predetermined intervals along the width direction of the sheet body. Similarly, the tips of the separation claws 24, 25 provided at a predetermined interval along the width direction of the sheet body 2 are in contact with the respective surfaces of the heat roller 10 and the pressure roller 11 while being biased with a predetermined pressure. The coil springs 24a and 25a are attached. Further, as shown in FIG. 1, one end of the coil spring 24a for urging the separation claw 24 is extended to the axis of the paper discharge roller 22 and is bent into a smooth curve so that it also serves as the guide member 16. You can The paper discharge fan 62 is driven by the motor 62a.

FIG. 3 is a front view showing a state in which the light source unit 70 in the erasing apparatus 1 of FIG. 1 is opened around the shaft 71. When the sheet body 2 is jammed at the subsequent stage of the heating roller pair 10 and 11, that is, when a so-called jam occurs, after the paper discharge tray 42 is removed in the state of FIG.
By manually moving the locking member 72 provided on the upper part of 0, the engagement between the claw 73 of the locking member 72 and the hole 74 formed in the housing 5 is released. And the light source unit 7
By tilting 0 to the outside, the heating roller pair 10, 11
A large space is formed on the discharge side of the light source, and the inside of the light source unit 70 can be easily seen, and the jam removal work by the user can be performed very safely and easily.

When the jam removing operation is completed, the light source unit 70 is pushed into the housing 5 to thereby cause the locking member 72.
The engagement between the claw 73 and the hole 74 of the housing 5 is easily restored.
In this way, by opening and closing the light source unit 70,
The jam removal work is simplified. The light source unit 7
0 may be a mechanism that moves horizontally by a linear guide means such as a rail, or may be a mechanism that is detachable from the main body of the erasing apparatus by using a detachable pivot shaft as the shaft 71.

FIG. 4 is an exploded perspective view showing the erasing unit 80. The erasing unit 80 includes the heating roller pair 10, 1
1, the cleaning rollers 20 and 21, and the guide member 4
0, 41, a light source unit 70, a bottom plate 4 for holding them, a casing 6, an auxiliary side plate 7 and the like, and an exhaust duct 65 for the heating roller pairs 10, 11 and the bottom plate 4.
An upper surface cover 81, which is mounted between the heating roller pair 10 and 11, is mounted between the heating roller pair 10 and 11 and is integrated with the exhaust duct 61. The pressure roller 11 is biased by the coil spring 82 against the heat roller 10.

The auxiliary side plate 7, which rotatably supports the heating roller pair 10, 11 and the cleaning rollers 20, 21 by a bearing such as a bearing, is detachably attached to the casing 6 by a fixing member 7a such as a screw. ing.
Therefore, as described above, each roller 10, 11, 2
Maintenance of 0 and 21 can be performed easily and quickly.

FIG. 5 is a partial block diagram showing the optical system of the light source 12 and the light condensing unit P. Some of the light emitted from the light source 12 reaches the light condensing part P directly, but most of the light is reflected by the reflecting mirrors 13a, 13b, 13c, and the reflecting mirror 1
The light reflected by 3b is directed to the condensing part P, while the reflection mirror 13
The light reflected by a and 13c is directed to the guide member 17 whose surface is a mirror surface, and is reflected there again to be collected in the light condensing unit P. In addition, the light guide 12 and the light condensing portion P are formed by forming the guide member 17 into a mirror-like shape and having a triangular cross-section.
By setting and in the regular reflection direction, the light collection efficiency can be further improved. Therefore, the guide member 17
Plays a role of smooth conveyance of the sheet body 2 and improvement of light collection efficiency. Even when the sheet body 2 passes over the guide member 17, the light from the light source 12 passes through the sheet body 2 while being attenuated to some extent, so that the light condensing action by the guide member 17 is continued. . Further, when the output of the light source 12 is large, the resin separation claw 24 may be overheated and deformed. Therefore, it is preferable to provide the metal protective cover 18 in front of the separation claw 24.

FIG. 6 shows a light source 12 and a heating roller pair 1.
It is a partial block diagram which shows the exhaust heat state of 0 and 11 vicinity. In order to erase the color of the decolorable toner efficiently and quickly, it is conceivable that the output efficiency of the light source 12 is increased and the output power of the light source 12 is increased in addition to the improvement of the light collection efficiency from the light source 12 to the light collecting portion P. It is necessary to exhaust the temperature-elevated air to the outside of the device while reducing the influence on the member. The light source 12 emits light having a wavelength distribution from visible light to far infrared and generates a large amount of heat. The temperature of the member that directly receives the light from the light source 12 rises due to light absorption, so that the temperature of the air near the light source 12 and the heating roller pair 10 and 11 becomes high. Therefore, the exhaust duct 61 connected to the exhaust fan 62 is provided near the upper portion, and the exhaust duct 65 connected to the exhaust fan 66 is provided near the lower portion. Further, by providing the heat-resistant glass plates 14 and 15 between the light source 12 and the light condensing unit P, it is possible to smooth the air flow without blocking the light from the light source 12 so much. It is possible to prevent the accumulation of internal air. Further, ventilation efficiency is improved by exhausting air from both sides of the conveyance path of the sheet body 2, and deformation of the sheet body 2 such as warpage and corrugation due to the exhaust pressure difference on both sides of the sheet body 2 is prevented. It is possible to suppress the jam occurrence rate.

FIG. 7 is a cutaway front view showing the operation panel 91 of the erasing apparatus 1 shown in FIG. By pressing the operation switch 92 of the operation panel 91, the sheet bodies 2 stored in the paper feed cassette 30 are taken out one by one, and the erasing process is continuously performed. It is also possible to set such that one sheet body 2 is processed by one switch operation.

On the other hand, by operating the speed adjusting knob 93, each of the rollers 34, 35, 38, 39, 10, 1.
The rotation speed of the drive motor 90, which is the power source of 1, 22, 23, is controlled, and the conveyance speed of the sheet body 2 can be set to a desired speed. Therefore, in the case of processing the sheet body 2 that is easily erased or in the case where a slight amount of unerased residue is acceptable, a rapid decoloring process can be performed by increasing the transport speed of the sheet body 2. Further, when processing the sheet body 2 that is difficult to be erased, by setting the conveying speed of the sheet body 2 to be slow, it is possible to perform a reliable erasing treatment by sufficient heating and light irradiation. Further, the sheet body that is not erased even by one-time erasing process is again fed to the sheet feeding cassette 30.
By performing the erasing process many times after returning to step 1, the erasing can be performed more reliably.

Next, the erasing unit according to the present invention will be described. FIG. 8 is a front view showing the internal structure of the erasing unit 101 which is another embodiment of the present invention. The erasing unit 101 includes a heating roller 110 and a pressing roller 1.
A pair of heating rollers 110 and 111 each including 11, a light source 112 that emits near infrared rays such as a halogen lamp, reflecting mirrors 113a and 113b having a concave shape and a reflecting mirror 113c having a flat portion, and heat-resistant glass plates 114 and 115.
And a guide member 1 for smoothly guiding a sheet body such as paper or a plastic sheet carried in through the carry-in port 109a.
40, 141, 116, 117, discharge rollers 122, 123 for conveying the sheet body, and a bottom plate 104, a top plate 108, a front plate 109b, for accommodating these inside.
It is composed of a box body composed of 109c and the like. It should be noted that in order to provide compatibility with the conventional fixing device, FIG.
It is preferable that the ratio of the height to the width of the erasing unit, ie, the aspect ratio, is in the range of 0.7 to 1.6.

The heating roller 110 is a hollow cylindrical roller made of metal or glass whose surface is coated with fluororesin or the like, and has a heater 110a such as a halogen lamp incorporated in the shaft center portion thereof. The surface of the roller is heated to a predetermined temperature by the energization of. The pressing roller 111 is a metal roller whose surface is thickly coated with silicone rubber. The pressing roller 111 is biased against the heating roller 110 by a predetermined pressure, so that the heating roller 11 is pressed.
The silicone rubber elastically deforms along the outer peripheral shape of 0 to secure a predetermined contact area.

From the carry-in port 109a formed in the front plates 109b and 109c, the sheet body to which the photochemically decolorizable toner as described above is fixed is conveyed along the alternate long and short dash line in FIG. When the leading end of the sheet reaches the heating roller pair 110, 111 through the guide members 140, 141, the heating roller pair 110, 111 rotates at a predetermined rotation speed.
By being conveyed while being sandwiched by the toner, the toner is heated to the glass transition temperature of the binder resin or higher.

On the discharge side of the heating roller pair 110, 111, the light including the near infrared rays emitted from the light source 112 such as a halogen lamp is reflected by the reflecting mirrors 113a, 113b, 113c.
As a result, the light condensing portion P that is efficiently collected and has a high light irradiation density is formed.

FIG. 9 is a partial block diagram showing the optical system of the light source 112 and the light condensing unit P. Some of the light emitted from the light source 112 reaches the light condensing part P directly, but most of the light is reflected by the reflecting mirrors 113a, 113b, 113c, and the light reflected by the reflecting mirror 113b is the light collecting part. On the other hand, the light reflected by the reflecting mirrors 113a and 113c is directed to P, travels toward the guide member 117 whose surface is a mirror surface, and is reflected there again to be collected in the condensing unit P. In addition, the light-collecting efficiency can be further improved by forming the guide member 117 into a mirror surface and forming the cross-sectional shape into a triangular wave shape to set the light source 112 and the light-collecting portion P in the regular reflection direction. Therefore, the guide member 117 plays a role of smooth conveyance of the sheet body 102 and improvement of light collection efficiency. In addition,
Even when the sheet body 102 passes over the guide member 117, the light from the light source 112 passes through the sheet body 102 while being attenuated to some extent, so that the light condensing action by the guide member 117 is continued.

In this way, the sheet body is composed of the heating roller pair 11
When the toner is discharged from No. 0, 111, the near-infrared light is immediately irradiated, so that the color of the toner is efficiently erased. The erased sheet body is the guide member 11
6, 117, and discharge rollers 122, 12
3 is discharged to the outside. The guide member 116 is composed of a plurality of linear members formed by bending such as wire, and is arranged at a predetermined interval along the conveying direction of the sheet body.

In this way, the sheet body recorded with the toner is erased efficiently and quickly while being conveyed along the one-dot chain line in the figure.

Heating roller 110 and pressing roller 111
The cleaning rollers 120 and 121 capable of being impregnated with a releasing agent such as silicone oil are in contact with each other, and by moistening the surfaces of the heating roller pairs 110 and 111 with the releasing agent, a sheet body is formed. It prevents the adhesion of fixed toner and the winding of the sheet. Further, the separation claws 124 and 125 are in contact with the vicinity of the discharge side of the heating roller 110 and the pressing roller 111, respectively, and even when the sheet body is in close contact with the heating roller pair 110 and 111, the tip ends of the separation claws 124 and 125. Enables the sheet body to be peeled off and prevents the sheet body from being wrapped around. A metal protective cover 118 is provided in order to prevent light from the light source 112 from hitting the resin separation claw 124 and being overheated and deformed.

By providing the sheet body detection sensor 152 such as a photo coupler or a micro switch on the discharge side of the discharge rollers 122 and 123, it is possible to perform timing control and jam occurrence detection. In addition, the pressing roller 11
Static elimination brushes 156 and 157 are provided on the surface of No. 1 and on the discharge side of the discharge rollers 122 and 123 to prevent occurrence of electrostatic attraction of the sheet body.

A temperature sensor 153 such as a bimetal or thermistor is provided on the surface of the heating roller 110 to control the temperature of the heating roller 110. Also,
Thermal fuses 154, 155, and 156 are provided on a portion where the temperature rises significantly, for example, on the front surface of the heating roller 110 and the rear surface of the reflecting mirror 113b and the guide member 117,
Prevents the generation of abnormally high temperatures.

Since a large amount of heat is generated in the vicinity of the heating roller pair 110, 111 and the light source 112, exhaust ducts 161, 1 are provided on both upper and lower sides of the sheet conveying path (one-dot chain line in the figure).
The temperature rise in the erasing unit 101 is prevented by installing 65 and forcibly exhausting by an exhaust fan provided outside.

FIG. 10 is a partial configuration diagram showing a heat exhaust state in the vicinity of the light source 112 and the heating roller pair 110, 111. In order to erase the color-erasable toner efficiently and quickly, it is conceivable to increase the light-collecting efficiency from the light source 112 to the light-collecting section P and to increase the output of the light source 112. It is necessary to exhaust the temperature-elevated air to the outside of the device while reducing the influence on the member. The light source 112 emits light having a wavelength distribution from visible light to far infrared and generates a large amount of heat. The temperature of the member that directly receives the light from the light source 112 rises due to the light absorption, so that the temperature of the air near the light source 112 and the heating roller pair 110 and 111 becomes high. Therefore, the exhaust duct 161 connected to the exhaust fan 162 is provided near the upper portion, and the exhaust duct 65 connected to the exhaust fan 166 is provided near the lower portion. Further, by providing the heat-resistant glass plates 114 and 115 between the light source 112 and the light condensing part P, it becomes possible to smooth the air flow without blocking the light from the light source 112 so much. It is possible to prevent the accumulation of internal air. Further, ventilation efficiency is improved by exhausting air from both sides of the conveying path of the sheet body 102, and deformation of the sheet body 102 such as warpage and corrugation due to the exhaust pressure difference on both sides is prevented. It is possible to suppress the jam occurrence rate.

FIG. 11 shows the erasing unit 101 shown in FIG.
FIG. The shaft 120a of the cleaning roller 120 of FIG. 8 is biased against the heating roller 110 by a spring 121b via a bearing, while the shaft 121a of the cleaning roller 121 is pressed by a spring 121b against a pressing roller 111 via a bearing. Being energized. The end of the heating roller 110 is covered with a protective cover 110b. A knob 111g for manual rotation is attached to one end of the shaft of the pressing roller 111. In addition, in order to bias the pressing roller 111 against the heating roller 110, the pulling spring 111f locked to the side plate 106a is
A lever 111e that can be angularly displaced about a fulcrum 111i
The free end of the roller is pulled by a predetermined force, and the lever 111e presses the bearing of the pressing roller 111 against the heating roller 110.

Electrode 11 for holding and energizing light source 112
2a is provided. In addition, the discharge rollers 122 and 1 of FIG.
The shaft 122a of the discharge roller 122 is biased toward the shaft 123b of the discharge roller 123 by a spring 122b via a bearing in order to bring the 23 into close contact with each other.

FIG. 12 shows the erasing unit 101 shown in FIG.
FIG. An electrode 110c is provided for holding and energizing the heater 110a provided at the axis of the heating roller 110, and a gear 110d for transmitting the rotation of the heating roller 110 meshes with the gear 143 and the gear 142b. There is. The shaft 111a and the bearing 111b of the pressing roller 111 are urged against the heating roller 110 by a lever 111c pulled by a pulling spring 111d locked to the side plate 106b, as described above. Gear 1
A driving force is supplied to 42a from an external driving system (not shown), and a gear 142b integrated with the gear 142a drives the gear 120d of the cleaning roller 120 and the gear 110d of the heating roller 110. Also, gear 1
10d and the gear 143 mesh with each other, and the gear 143 and the gear 14
4b meshes with each other, and the gear 144a integrated with the gear 144b meshes with the gear 123c of the discharge roller 123, so that the discharge rollers 122 and 123 are driven at a predetermined rotation speed. A pull-out hole 190 for pulling out the electric cable is provided in the lower portion of the side plate 106b.

FIG. 13 shows the erasing unit 101 shown in FIG.
3 is a partial cross-sectional view taken along line AA and line BB of FIG.
The heating roller 110, the pressing roller 111, and the cleaning rollers 120 and 121 are rotatably supported with respect to the side plate 106b and the auxiliary side plate 107, and the heater 110a such as a halogen lamp is provided at the axis of the heating roller 110. It is held by the electrode 110c. Therefore, when replacing the rollers 110, 111, 120, 121, without disassembling the entire box body including the side plates 106a, 106b, the top plate 108, the bottom plate 104, and the like,
Maintenance workability is improved because it is sufficient to remove only the auxiliary side plate 107.

As shown in the broken central portion of FIG. 13, a plurality of discharge rollers 122 and 123 are provided on the shafts 122a and 123b at predetermined intervals along the width direction of the sheet body.
Similarly, the tip ends of the separation claws 124 and 125 provided at a predetermined interval along the width direction of the sheet body have the heating roller 11
0 and the surfaces of the pressing roller 111 are contacted while being biased by a predetermined pressure.
5a is attached. Further, as shown in FIG. 8, one end of the coil spring 124a for urging the separation claw 124 is extended to the shaft 122a of the discharge roller 122, and is bent into a smooth curve so that it also serves as the guide member 116. There is.

FIG. 14 shows the erasing unit 101 shown in FIG.
FIG. 4 is a partial cross-sectional view and a plan view taken along line CC of FIG. As shown in the lower left part of FIG. 12, the heating roller 110 is pivotally supported by the side plate 106b and is coupled to the gear 110d, and the gear 110d and the gear 142b are meshed with each other. On the other hand, the shaft 123b of the discharge roller 123 is connected to the gear 123c, and meshes with the gear 123c and the gear 144a. On the other hand, as shown in the upper right part of FIG. 14, an exhaust duct 161 is provided on the top plate 108.

FIG. 15 shows the erasing unit 101 shown in FIG.
FIG. 3 is an exploded perspective view of a box body that constitutes the. Decoloring unit 10
The box body 1 includes a bottom plate 104, two side plates 106a and 106b standing on both ends of the bottom plate 104, and each side plate 106.
and a front plate 109b, 109c forming a sheet inlet, and a back plate 170a on the sheet discharge side,
The bent portions formed at these ends are screwed so as to be surface-bonded to each other. In particular, the bottom plate 104 and each side plate 1
Mounting holes 2 that are screwed to each other on 06a and 106b
12a and 212b are formed, a positioning hole 210 is formed when the erasing unit 101 is incorporated into another device, and mounting holes 211a and 211b for fixing the entire erasing unit 101 are formed. In addition,
The back plate 170a is pivotally supported by a shaft 171 so that it can be angularly displaced with respect to the side plates 106a and 106b. Further, by forming the intake port 170b above the sheet discharge port of the back plate 170a, it is possible to prevent the corrugation phenomenon and vibration of the sheet body due to the inflow of air from the discharge port.

FIG. 16 shows the erasing unit 101 shown in FIG.
FIG. Between the front plates 109b and 109c to which the guide members 140 and 141 are attached, there is provided a carry-in port 109a into which the sheet body is loaded, and the top plate 108 provided with the exhaust duct 161 is mounted above the carry-in port 109a. .
Further, an exhaust duct 165 is provided on the inner bottom plate 104. The auxiliary side plate 107 that pivotally supports one end of each of the rollers 110, 111, 120, 121 is detachably attached to the side plate 106a by a fixing member such as a screw.

Further, the light source housing portion 170 housing the light source 112 is provided with a shaft by releasing the engagement between the claw 173 of the locking member 172 and the hole 174 formed in the top plate 108 shown in FIG. It is possible to tilt the unit 171 outward. In this way, a large space is formed on the discharge side of the heating roller pair 110 and 111, so that even when a sheet is jammed in the conveying path, that is, when a so-called jam occurs, the user can safely and easily remove the jam. It becomes possible to do. When the jam removal work is completed, the light source storage unit 170 is pushed into the box body, so that the engagement between the claw 173 of the locking member 172 and the hole 174 of the top plate 108 is easily restored. By opening and closing the light source storage unit 170 in this way, the jam removal operation is simplified. The light source storage unit 170 may be a mechanism that moves horizontally by a linear guide means such as a rail, or may be a mechanism that detaches from the single unit by adopting a detachable pivot shaft as the shaft 171.

FIG. 17 shows an erasing unit 10 according to the present invention.
1 is a front view showing an internal configuration of a color erasing device 200 incorporating 1. The erasing device 200 includes an erasing unit 101 including a heating roller pair 110 and 111 including a heating roller 110 and a pressing roller 111, a light source 112, reflecting mirrors 113a to 113c, and discharge rollers 122 and 123, and the above-described photochemical. A sheet feeding cassette 202 for accommodating a sheet body having decolorizable toner fixed thereon, sheet feeding rollers 231 and 232 for taking out the sheet bodies one by one from the sheet feeding cassette 202, and a sheet body 1 in FIG. Transport rollers 234, 235, 238, 23 for transporting along the dotted line
9 and a guide member 23 for smoothly guiding the sheet body
3, 236, 237, a discharge tray 203 for receiving the sheet body that has been subjected to the erasing process, exhaust fans 162, 166 for exhausting heat generated in the erasing unit 101 to the outside through exhaust ports 164a, 164b, and Exhaust duct 16
3, 167 and the like.

In the vicinity of the upper part of the conveying path of the guide member 236,
A sheet body detection sensor 251 is installed for timing control, jam occurrence detection, and the like. Further, a motor 240, which is a drive source for driving each roller in the erasing apparatus 200, is attached above this. These are housed in the housing 201. Further, the erasing unit 101 is fixed to the bottom of the erasing apparatus 200 by screwing or the like.

FIG. 18 is a rear view of the erasing device 200 shown in FIG. The gear 242 fixed to the output shaft 241 of the motor 240 meshes with the gear 243, and the gear 24
3 and the gear 244 mesh with each other to transmit the rotational driving force to the gear 142a of the erasing unit 101. Further, the gear 142a drives each roller in the erasing unit 101 and meshes with the gear 248 of the erasing apparatus 200 to drive the gear 239b of the conveying roller 239.
39b and the gear 247 mesh with each other, and further the transport roller 23
The gear 235b of No. 5 is rotationally driven. Furthermore, gear 2
35b, via the gears 245, 246, the paper feed roller 2
32 gear 232b is being driven. The shaft 238a of the transport roller 238 is urged against the transport roller 239 by a spring 238b via a bearing. A power switch 191 of the erasing device 200 is provided on the lower right side of the side plate 106b of the erasing unit 101.

In this way, since the erasing unit 101 for performing the erasing heat treatment and the near-infrared treatment is small and is integrated in a box shape, the erasing apparatus 200 incorporating this is also small. And can be realized as a compact device.

FIG. 19 is a front view showing a state in which the light source housing 170 in the erasing apparatus 200 of FIG. 17 is opened around the shaft 171. When the sheet body is jammed on the discharge side of the heating roller pair 110 and 111, that is, when a so-called jam occurs, after the sheet discharge tray 203 is removed in the state of FIG. 17, a member provided on the upper portion of the light source storage unit 170. Stop member 1
By manually moving 72, the engagement between the claw 173 of the locking member 172 and the hole 174 formed in the top plate 108 is released. Then, by tilting the light source storage unit 170 outward, a large space is formed on the discharge side of the heating roller pair 110, 111, and the inside of the light source storage unit 170 becomes easily visible, which makes it extremely easy for the user to remove jams. It is possible to do it safely and easily.

When the jam removal work is completed, the light source storage portion 170 is pushed inward, so that the locking member 172 is released.
The engagement between the claw 173 and the hole 174 is easily restored. In this way, by opening and closing the light source storage unit 170, the jam removal work is simplified. The light source storage unit 170 may be a mechanism that moves horizontally by a linear guide means such as a rail, or may be a mechanism that detaches from the main body of the erasing apparatus by adopting a detachable pivot shaft as the shaft 171.

FIG. 20 is a cutaway front view showing the operation panel 291 of the erasing apparatus 200 shown in FIG. By pressing the operation switch 292 of the operation panel 291, the sheet bodies 102 accommodated in the paper feed cassette 202 are taken out one by one, and the erasing process is continuously performed. It is also possible to set such that one sheet 102 is processed by one switch operation.

On the other hand, by operating the speed adjusting knob 293, each roller 234, 235, 238, 23
The rotation speed of the motor 240, which is the power source of 9, 110, 111, 122, and 123, is controlled, and the conveyance speed of the sheet body 102 can be set to a desired speed. Therefore, in the case of processing the sheet body 102 that is easily erased or in the case where there is a small amount of unerased remaining, it is possible to speed up the decoloring process by increasing the transport speed of the sheet body 102. In addition, the sheet body 102 that is difficult to be erased
In the case of processing, by setting the conveyance speed of the sheet body 102 to be slow, it is possible to perform reliable decoloring processing by sufficient heating and light irradiation. Further, the sheet body that has not been erased even by one-time erase processing can be erased more reliably by returning it to the sheet feeding cassette 202 again and performing the erase processing many times.

FIG. 21 is a sectional view showing the internal structure of the erasing unit 101a according to another embodiment of the present invention. This erasing unit 101a is similar to that shown in FIG.
A pair of heating rollers 110 and 111 including a heating roller 110 and a pressing roller 111, a light source 112 that emits near infrared rays such as a halogen lamp, and reflecting mirrors 113a to 113a.
c, heat-resistant glass plates 114, 115, and guide members 116, 117, 140, 1 for smoothly guiding the sheet body.
41 and a discharge roller 122 for conveying the sheet body,
123 and the bottom plate 104 for storing these inside,
The top plate 108, the front plate 109, and the like are configured by a box body or the like. The exhaust duct 161 is provided on the top plate 108.
An exhaust fan 162 and an exhaust duct 163 are provided corresponding to the opening of the. An exhaust duct 165 for exhausting the heat generated in the erasing unit 101a is provided inside the upper surface of the bottom plate 104.

FIG. 22A shows the erasing unit 10 of FIG.
FIG. 22 is a perspective view showing a state in which the paper discharge tray 203 is mounted on the sheet No. 1, and FIG. A cover 170 is provided outside the light source housing 170 of the erasing unit 101.
b is attached, and the mounting hole 206 is provided below the cover 170b.
a and 206b are formed. On the other hand, the paper ejection tray 20
Projection 204 having locking claws 205a, 205 at the end of 3
a, 204b are formed, and the projections 204a, 204
By inserting b into the mounting holes 206a and 206b respectively, the locking claws 205a,
205b engages with the upper ends of the mounting holes 206a and 206b. In this way, the paper discharge tray 203 can be easily attached and detached.

FIG. 23 shows the erasing unit 10 according to the present invention.
FIG. 24 is a cross-sectional view showing the internal structure of an electrophotographic apparatus 300 in which 1 is incorporated, and FIG. 24 is an electrophotographic apparatus 300 shown in FIG.
FIG. The electrophotographic apparatus 300 includes a document table 310 on which a document is placed, a right cylindrical photosensitive member 304,
A charger 309 that charges the surface of the photoconductor 304, an exposure optical system 311 that scans and exposes a document and forms an image of reflected light on the surface of the photoconductor 304, and a charging device 309 formed on the surface of the photoconductor 304. A developing device 312 for developing toner by attaching toner to the electrostatic latent image, a manual feed tray 313 for supplying a recording medium such as paper, and paper feed cassettes 314a and 314b.
A transfer device 315 for transferring the toner on the photoconductor 304 to the recording medium, a conveying means 316 such as an endless belt for conveying the recording medium on which the toner is transferred, and the photoconductor 30.
4 includes a cleaner 315 that removes the toner remaining on the recording sheet 4, the erasing unit 101 according to the present invention, and a discharge tray 317.

As shown in FIG. 8, the erasing unit 101 includes a pair of heating rollers 110 and 111 composed of a heating roller and a pressing roller 111, and a light source 11 for emitting near infrared rays.
It is equipped with 2. First, when a normal copying operation is performed, the switch 302 for switching the copying / decoloring operation shown in FIG. 24 is set to copy and the print button 301 is pressed, and the surface of the photoconductor 304 charged by the charger 309 is touched. The exposure optical system 311 forms the reflected light from the original to form an electrostatic latent image, the developing device 312 develops the toner on the photoconductor 304, and the recording medium is supplied from, for example, the paper feed cassette 314a. Photoconductor 30
4 the developed toner is transferred. Further, the recording medium on which the toner is transferred is conveyed by the conveying unit 316.
It is conveyed to the erasing unit 101. Decoloring unit 101
Then, the heating roller pair 110 and 111 heat and melt the toner, fix the toner on the recording medium, and discharge the toner to the discharge tray 317. At this time, the light source 112 of the erasing unit 101 is not turned on. In this way, the erasing unit 101 can also be used as a toner fixing device.

Next, when the erasing operation is performed, the sheet body to which the erasing toner is fixed in advance is applied to, for example, the sheet feeding cassette 314b.
24, and when the erasing switch 303 shown in FIG. 24 is pressed, the sheet bodies are taken out one by one from the paper feeding cassette 314b, and the erasing unit 101 is conveyed by the conveying means 316.
Be delivered to. In the erasing unit 101, the heating roller pair 110, 111 heats the sheet body to a temperature not lower than the glass transition temperature of the binder resin of the toner, and thereafter, the near-infrared rays are irradiated by the light source 112, whereby the sheet body is heated. The upper toner is decolored and is discharged to the discharge tray 317.

In this way, the heating roller pair 110, 111 of the erasing unit 101 according to the present invention has both the fixing function for electrophotography and the erasing function for sheet body reproduction, thereby reducing the size of the entire apparatus. And space saving can be achieved.

[0083]

As described in detail above, according to the present invention,
Since it is possible to improve the heating efficiency and the light irradiation efficiency of the sheet body, it is possible to perform the toner decoloring process efficiently and quickly, and at the same time, suppress the temperature rise in the device, while being small and lightweight. An erasing device can be provided.
Further, even when the sheet body is clogged on the discharge side of the heating roller pair, the sheet body can be quickly taken out, and the light source unit can be easily inspected and cleaned. In addition, since the conveyance speed of the sheet body can be adjusted according to the decoloring performance of the toner fixed on the sheet body,
The erasing processing condition required by the user can be arbitrarily set. Moreover, maintenance such as replacement, repair, inspection, and cleaning of the heating roller becomes easy, so that maintenance cost can be reduced.

As described above, when the sheet body is reused by using the erasing apparatus according to the present invention, a large-scale facility is not required, and the reuse in each company is easy.

Further, according to the present invention, it is possible to efficiently and quickly perform the decoloring process of the toner fixed on the sheet body, and the influence of the heat generated inside to the outside is reduced. In addition, it is possible to realize a small and lightweight decoloring device.

Further, even when the erasing unit according to the present invention is incorporated into an electrophotographic apparatus, the overall size and weight of the apparatus can be reduced.

[Brief description of drawings]

FIG. 1 is a front view showing a configuration of an erasing device which is an embodiment of the present invention.

FIG. 2 is a cutaway side view showing a schematic configuration of the erasing device 1 of FIG.

3 is a front view showing a state in which a light source unit 70 in the erasing device 1 of FIG. 1 is opened around a shaft 71. FIG.

FIG. 4 is an exploded perspective view showing a erasing unit 80.

FIG. 5 is a partial configuration diagram showing an optical system of a light source 12 and a condensing unit P.

FIG. 6 is a partial configuration diagram showing a heat exhaust state in the vicinity of a light source 12 and a pair of heating rollers 10 and 11.

7 is a cutaway front view showing an operation panel 91 of the erasing apparatus 1 of FIG.

FIG. 8 is a erasing unit 101 which is another embodiment of the present invention.
FIG. 3 is a front cross-sectional view showing the internal configuration of FIG.

FIG. 9 is a partial configuration diagram showing an optical system of a light source 112 and a condensing unit P.

FIG. 10 shows a light source 112 and a pair of heating rollers 110 and 11.
It is a partial block diagram which shows the exhaust heat state of 1 vicinity.

11 is a front view of the erasing unit 101 shown in FIG.

12 is a rear view of the erasing unit 101 shown in FIG.

13 is a partial cross-sectional view of the decoloring unit 101 shown in FIG. 8 taken along the lines AA and BB.

14A and 14B are a partial cross-sectional view and a plan view of the erasing unit 101 shown in FIG. 8 taken along the line C-C.

15 is an exploded perspective view of a box body that constitutes the erasing unit 101 shown in FIG.

16 is a perspective view of the erasing unit 101 shown in FIG.

FIG. 17 is a front view showing the internal structure of a erasing device 200 incorporating the erasing unit 101 according to the present invention.

FIG. 18 is a rear view of the erasing device 200 shown in FIG.

FIG. 19 is a light source storage unit 1 in the erasing apparatus 200 of FIG.
It is a front view which shows the state which 70 opened centering around the axis | shaft 171. FIG.

20 is an operation panel 2 of the erasing device 200 shown in FIG.
It is a fracture front view showing 91.

FIG. 21 is a erasing unit 10 which is another embodiment of the present invention.
It is sectional drawing which shows the internal structure of 1a.

22 (a) is a erasing unit 101 of FIG.
FIG. 22 is a perspective view showing a state in which the paper discharge tray 203 is mounted, and FIG. 22 (b) is a partial sectional view thereof.

FIG. 23 is a cross-sectional view showing the internal configuration of an electrophotographic apparatus 300 incorporating the erasing unit 101 according to the present invention.

24 is a cutaway plan view of the electrophotographic apparatus 300 shown in FIG.

[Explanation of symbols]

1 Decoloring device 2 Sheet body 4 Bottom plate 5 Cover 6 Housing frame 7 Auxiliary side plate 10 Heat roller 11 Pressure roller 12 Light source 13a, 13b, 13c Reflecting mirror 14, 15 Heat-resistant glass plate 16, 17, 33, 36, 37, 40 , 41 Guide member 18 Protective cover 20, 21 Cleaning roller 22, 23 Paper discharging roller 24, 25 Separation claw 31, 32 Paper feeding roller 30 Paper feeding cassette 34, 35, 38, 39 Conveying roller 42 Paper discharging tray 61, 63, 66,67 Exhaust duct 62,66 Exhaust fan 70 Light source unit 80 Decoloring unit 101 Decoloring unit 102 Sheet body 104 Bottom plate 106a, 106b Side plate 107 Auxiliary side plate 108 Top plate 109 Front plate 109a Carrying inlet 110 Heating roller 110a Heater 110d, 142a , 142b, 144a, 144b
Gear 111 Pressing roller 112 Light source 113a, 113b, 113c Reflecting mirror 114, 115 Heat resistant glass plate 116, 117, 140, 141 Guide member 118 Protective cover 122, 123 Discharging roller 120, 121 Cleaning roller 124, 125 Separation claw 161, 163, 165, 167 Exhaust duct 162, 166 Exhaust fan 162a, 166a Motor 170 Light source storage 170a Back plate 203 Paper ejection tray

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masakazu Okamoto 3-2-15 Meiwadori, Hyogo-ku, Kobe City, Hyogo Prefecture Bando Kagaku Co., Ltd. (72) Inventor's view, Yasunori 3 Meiwadori, Hyogo-ku, Kobe-shi 2-15, Bando Kagaku Co., Ltd. (72) Inventor Katsumi Murofushi 5-1 Ogimachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Showa Denko Co., Ltd. Chemicals Research Laboratory (72) Inventor, Kiichi Hosoda Ogi-machi, Kawasaki-shi, Kanagawa No. 5 No. 1 Showa Denko Chemicals Laboratory

Claims (8)

[Claims] 1. A heating unit for heating a photochemically decolorizable toner fixed on a sheet member to at least a glass transition temperature of a binder resin of the toner, and a near infrared ray to the toner. A light source for irradiating, and a light collecting means for collecting the light from the light source to form a light collecting portion on the discharge side of the heating means, and between the light source and the heating means, An erasing device, characterized in that exhaust ducts are provided above and / or below a sheet conveying path. 2. A heating means for heating a photochemically decolorizable toner fixed on a sheet member to at least a glass transition temperature of a binder resin of the toner, and a near infrared ray to the toner. A light source for irradiating and a light collecting means for collecting light from the light source to form a light collecting portion on the discharge side of the heating means are provided, and the light source and the light collecting means are integrally included. The erasing device, wherein the light source unit is displaceable relative to the heating means. 3. A heating means for heating a photochemically decolorizable toner fixed on a sheet member to at least a glass transition temperature of a binder resin of the toner, and a near infrared ray to the toner. A light source for irradiating and a light collecting unit for collecting light from the light source to form a light collecting unit on the discharge side of the heating unit are provided, and the conveyance speed of the sheet body is variable. Characteristic erasing device. 4. A heating unit for heating a photochemically decolorizable toner fixed on a sheet member to at least a glass transition temperature of a binder resin of the toner, and a near infrared ray to the toner. A light source for irradiating and a light collecting means for collecting light from the light source to form a light collecting portion on the discharge side of the heating means, and a support member for supporting the heating means is removable. An erasing device characterized in that 5. A heating means for heating a photochemically decolorizable toner fixed on a sheet member to at least a glass transition temperature of a binder resin of the toner, and a near infrared ray to the toner. A light source for irradiating, a light collecting means for collecting light from the light source to form a light collecting part on the downstream side of the heating means for conveying the sheet body, the heating means, the light source and the light collecting means. An erasing unit, characterized in that it comprises a box for accommodating the inside. 6. The box body, a bottom plate, two side plates standing on both sides of the bottom plate, a top plate connecting the upper ends of the side plates, a front plate having a carry-in port for the sheet body, The erasing unit according to claim 5, wherein the erasing unit comprises a light source and a light source housing member that houses the light collecting means. 7. The erasing unit according to claim 5, wherein the heating means is capable of heating and melting the unfixed toner on the sheet body and fixing it on the sheet body. 8. The erasing unit according to claim 5, wherein a discharge tray is detachably attached to the light source storage member.