JP2014164030A - Image decoloring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily maintain the performance characteristic of a peripheral device by preventing the device from being heated by heat used for decoloring of an image.SOLUTION: An image decoloring apparatus includes: a heating part for heating a recording medium to a temperature equal to or higher than a temperature for decoloring a colorant; a conveyance part for conveying the recording medium which has passed through the heating part; a peripheral device existing near the heating part; and a heat storage part for absorbing heat which goes to the peripheral device from the heating part.

Description

  Embodiments relate to an image erasing apparatus that heats a sheet and erases an image formed on the sheet.

  There is an image erasing apparatus that heats a sheet and erases a formed image on the sheet for reuse. On the other hand, there is a need to prevent the heat used to erase the formed image from heating the peripheral device.

JP 2010-113337 A JP 2011-209711 A

  The problem to be solved by the present invention is to provide an image erasing device that prevents the heat used for erasing the formed image on the sheet from heating the peripheral device and maintains the performance characteristics of the peripheral device well. Is to provide.

  In order to achieve the above object, an image erasing apparatus according to an embodiment includes a heating unit that heats a recording medium to a color erasing temperature of a colorant or more, a conveyance unit that conveys the recording medium that has passed through the heating unit, A peripheral device located around the heating unit, and a heat storage unit that absorbs heat reaching the peripheral device from the heating unit.

The schematic block diagram which shows the decoloring apparatus of 1st Embodiment. Schematic explanatory drawing which shows the decoloring part of 1st Embodiment. Schematic explanatory drawing which shows an example of the detail of the cooling guide of 1st Embodiment. The graph which shows transition of the surface temperature of the sensor of 1st Embodiment. The schematic block diagram which shows the decoloring apparatus of 2nd Embodiment.

  Embodiments will be described below.

(First embodiment)
The image erasing apparatus of the first embodiment will be described with reference to FIGS. FIG. 1 shows an example of an erasing apparatus 10 that is an image erasing apparatus. The decoloring apparatus 10 is, for example, a paper feeding unit 11, a transport mechanism 12, and a peripheral device, and includes a sensor 13 that is a reading unit, a decoloring unit 14 that is a heating unit, and a paper discharge mechanism 16.

  The paper feeding unit 11 feeds a sheet P that is a recording medium. The paper feed unit 11 includes a paper feed tray 11a for stacking sheets P having images formed with colorants that can be erased by heating, a pickup roller 11b for taking out the sheet P from the paper feed tray 11a, and a separation roller 11c. Prepare.

  The transport mechanism 12 transports the sheet P fed from the paper feed unit 11 toward the sensor 13, the erasing unit 14, or the paper discharge mechanism 16. The transport mechanism 12 includes a first transport path 20, a second transport path 21, and a third transport path 22 that is a transport unit. The first transport path 20 extends from the paper feeding unit 11 through the sensor 13 to the first branching unit 24a. The second conveyance path 21 extends from the first branch part 24 a to the decoloring part 14. The third conveyance path 22 reaches from the decoloring section 14 to the junction 26 upstream of the sensor 13. That is, a circulation type conveyance path is formed by a part of the first conveyance path 20, the second conveyance path 21, and the third conveyance path 22, and the sensor 13 is disposed at a predetermined position of the circulation type conveyance path. .

  The sensor 13 includes a first sensor 13a and a second sensor 13b that face each other with the first conveyance path 20 interposed therebetween. The first sensor 13a and the second sensor 13b are, for example, a CCD (Charge Coupled Device) scanner or a CMOS sensor. The first sensor 13 a reads the surface of the sheet P passing through the first transport path 20, and the second sensor 13 b reads the back surface of the sheet P passing through the first transport path 20.

  For the first sensor 13a and the second sensor 13b, the absolute maximum rated temperature is defined as, for example, (temperature t2). If the first sensor 13a and the second sensor 13b are heated to the absolute maximum rated temperature or higher, a good reading result cannot be obtained, and there is a risk of damage.

  The erasing unit 14 heats the sheet P to erase the colorant of the image formed on the sheet P. The decoloring unit 14 heats the sheet P to a temperature equal to or higher than the decoloring temperature at which the colorant decolors. As shown in FIG. 2, the erasing unit 14 includes a first erasing unit 31 for erasing the image on the front side of the sheet P and a second erasing unit for erasing the image on the back side opposite to the front side of the sheet P A color unit 32 is provided. The first erasing unit 31 includes a heat roller 31b, a press roller 31c, and a temperature sensor 31d that incorporate a heat lamp 31a. The second erasing unit 32 includes a heat roller 32b that incorporates a heat lamp 32a, a press roller 32c, and a temperature sensor 32d.

  The paper discharge mechanism 16 classifies and discharges the erased sheet P. The paper discharge mechanism 16 includes a paper discharge tray 36 that stores a sheet S1 that can be reused after erasing, and a reject tray 37 that stores a sheet S2 that cannot be reused. The paper discharge mechanism 16 includes a first paper discharge path 36a from the first branch section 24a to the paper discharge tray 36 via the second branch section 24b, and a second paper discharge path 37a from the second branch section 24b to the reject tray 37. Is provided.

  The third transport path 22 includes first to third transport rollers 27a, 27b, and 27c. There is an upper cooling guide 28a between the first conveyance roller 27a and the second conveyance roller 27b, and there is an upper and lower cooling guide 28b between the second conveyance roller 27b and the third conveyance roller 27c. A lower cooling guide 28 c exists between the junction 26. Each cooling guide 28a, 28b, 28c cools the sheet P heated by passing through the decoloring section 14.

  Although the cooling guides 28a, 28b, and 28c have different shapes and directions, the configuration is common. Accordingly, an example of the configuration of each cooling guide 28a, 28b, 28c will be described in detail using a part of the upper and lower cooling guide 28b shown in FIG.

  The lower guide plate 38 of the vertical cooling guide 28b is made of, for example, a copper plate having high thermal conductivity. The heat storage material 40 which is a heat storage part contacts the surface 38a of the guide plate 38 which opposes the contact surface with the sheet P. The heat storage material 40 includes a melting point that maintains a temperature (temperature t1) lower than the absolute maximum rated temperature (temperature t2) of the first sensor 13a and the second sensor 13b, for example. The heat storage material 40 uses, for example, sodium acetate that changes phase from solid to liquid at (temperature t1).

  For example, sodium acetate is applied to the guide plate 38 and the heat storage material 40 is fixed by an adhesive. The heat storage material 40 absorbs the heat of the sheet P that is thermally conducted from the guide plate 38. Due to the heat absorption of the heat storage material 40, the temperature of the sheet P heated by the decoloring section 14 is cooled below the absolute maximum rated temperature (temperature t1) of the first sensor 13a and the second sensor 13b.

  The material of the guide plate 38 or the heat storage material 40 is not limited as long as the sheet P can be cooled below the absolute maximum rated temperature. The material of the heat storage material 40 is arbitrary and is not limited to sodium acetate. The heat storage material 40 can adjust the melting point by changing the material used or changing the distribution of the material. Further, the heat storage material 40 may not be applied to the guide plate 38, but the guide plate 38 may be formed hollow and the heat storage material 40 may be enclosed inside. Furthermore, the number and arrangement positions of the cooling guides provided in the third conveyance path 22 are arbitrary.

  The detailed configuration of the upper cooling guide 28a, the upper side of the upper and lower cooling guide 28b, and the lower cooling guide 28c is the same as the configuration of the lower side of the upper and lower cooling guide 28b. Although not shown, the detailed configuration of the upper cooling guide 28a, the upper and lower cooling guides 28b, and the lower cooling guide 28c will be described using the same reference numerals used below the upper and lower cooling guides 28b.

  The upper cooling guide 28a, the upper side of the upper and lower cooling guides 28b, and the lower cooling guide 28c are all provided with a guide plate 38 having high thermal conductivity. The heat storage material 40 is applied to the surface 38a facing the contact surface of the sheet P on the upper cooling guide 28a, the upper side of the upper and lower cooling guides 28b, and the guide plate 38 of the lower cooling guide 28c.

  With these configurations, in order to reuse the sheet P, the sheet P is set on the paper feed tray 11a of the erasing apparatus 10 and the image erasing operation is started. The erasing apparatus 10 takes out the sheet P from the paper feed tray 11 a and conveys it to the sensor 13. The erasing apparatus 10 reads the sheet P with the first sensor 13a and the second sensor 13b. From the read result, if the sheet P can be reused, the decoloring apparatus 10 conveys the sheet P to the decoloring unit 14 via the first branching section 24a and the second conveyance path 21. If the sheet P is not suitable for reuse, the decoloring apparatus 10 classifies the sheet S2 that cannot be reused into the reject tray 37 from the first conveyance path 20 through the second discharge path 37a.

  The decoloring unit 14 decolorizes the image of the sheet P by heating both surfaces of the sheet P to the decoloring temperature of the colorant by the first decoloring unit 31 and the second decoloring unit 32. The third conveyance path 22 conveys the sheet P that has passed through the decoloring section 14 in the direction of the arrow q toward the first sensor 13a and the second sensor 13b again via the junction 26.

  The sheet P heated by the decoloring unit 14 contacts the cooling guides 28a, 28b, and 28c while passing through the third conveyance path 22. Each of the cooling guides 28a, 28b, 28c takes the heat of the sheet P by the heat conduction of the guide plate 38. The heat storage material 40 applied to each cooling guide 28a, 28b, 28c absorbs and stores heat taken from the sheet P by the guide plate 38. The sheet P is cooled to (temperature t1) or less while passing through the third conveyance path 22.

  The sheet P conveyed to the third conveyance path 22 and reaching the first sensor 13a and the second sensor 13b is cooled to (temperature t1) or less. Even when the first sensor 13a and the second sensor 13b read the sheet P that has passed through the decoloring section 14, the first sensor 13a and the second sensor 13b maintain a temperature equal to or lower than the absolute maximum rated temperature (t2). If the first sensor 13a and the second sensor 13b are equal to or lower than the absolute maximum rated temperature (t2), the first sensor 13a and the second sensor 13b read the sheet P with high accuracy while maintaining good reading characteristics.

  From the reading result of the sheet P by the first sensor 13a and the second sensor 13b after passing through the erasing unit 14, the erasing apparatus 10 determines whether the sheet P can be reused or cannot be reused. If the image is erased from the reading result, the erasing apparatus 10 determines that the sheet S1 is reusable and classifies the sheet S1 into the paper discharge tray 36. If the image is not erased from the reading result, the erasing apparatus 10 determines that the sheet S2 cannot be reused, and classifies the sheet S2 into the reject box 37.

  The heat storage material 40 absorbs heat until the heat storage capacity becomes full (temperature t1) and maintains the temperature below, and cools the sheet P passing through the third conveyance path 22 to (temperature t1) and below. When the heat storage capacity becomes full, the heat storage material 40 gradually radiates the accumulated heat, for example, gradually.

  In contrast to the first embodiment, if the sheet P that is not cooled in the third conveyance path 22 is conveyed to the sensor 13, the sensor 13 is heated by the sheet P and the temperature rises. If the sensor 13 is heated to a temperature higher than the absolute maximum rated temperature due to the passage of the high-temperature sheet P, the reading accuracy of the first sensor 13a or the second sensor 13b may be significantly impaired. The decoloring apparatus 10 according to the first embodiment cools the sheet P that has passed through the decoloring unit 14 while being transported through the third transport path 22 in order to maintain good reading accuracy of the sensor 13.

  The transition of the surface temperature of the sensor 13 during the erasing operation by the erasing apparatus 10 is shown by a solid line α in FIG. The sensor 13 reads the sheet P that is cooled to (temperature t1) or less by the heat absorption of the heat storage material 40 during the decoloring of the images at times s0 to s2. During the color erasing of the images at times s0 to s1, the surface temperature of the sensor 13 rises gradually from room temperature t0 to (temperature t1), for example.

  The heat storage material 40 cools the sheet P to (temperature t1) or less until the heat storage capacity becomes full. Even if the surface temperature of the sensor 13 reaches (temperature t1) at time s1, the surface temperature of the sensor 13 is maintained at (temperature t1) until the heat storage capacity of the heat storage material 40 becomes full. When the erasing operation is finished at time s2, the surface temperature of the sensor 13 is gradually cooled to room temperature t0. The surface temperature of the sensor 13 is kept below the absolute maximum rated temperature (temperature t2) during the decoloring operation. The sensor 13 that holds the absolute maximum rated temperature (t2) or lower maintains good reading accuracy and reliably reads the reusable sheet S1 and the non-reusable sheet S2.

  On the other hand, as a comparative example, when the decoloring operation was performed without using the heat storage material 40 in the cooling guide in the third conveyance path 22, the transition of the surface temperature of the sensor 13 became the broken line β in FIG. . In the comparative example, the surface temperature of the sensor 13 continues to rise by reading the heated sheet P that has passed through the erasing unit 14 during the erasing of time s0 to s2. In the comparative example, the surface temperature of the sensor 13 exceeds the absolute maximum rated temperature (temperature t2) of the sensor 13 and reaches a high temperature (temperature t3). The sensor 13 heated to the absolute maximum rated temperature (temperature t2) or more may significantly impair the reading accuracy of the sheet P and become unreadable and may possibly be damaged.

  According to the first embodiment, the third conveyance path 22 includes the heat storage material 40 having a melting point that maintains a temperature lower than the absolute maximum rated temperature of the sensor 13 (temperature t1). While the sheet P passes through the third conveyance path 22, the heat storage material 40 absorbs the heat of the sheet P heated by the decoloring section 14, and cools the sheet P to (temperature t1) or less. During the decoloring operation, the temperature of the sensor 13 is kept below the absolute maximum rated temperature, and the reading accuracy of the sheet P by the sensor 13 is kept good. The erasing apparatus 10 can reliably classify the reusable sheet P according to the reading result of the sensor 13.

(Second Embodiment)
An image erasing apparatus according to the second embodiment will be described with reference to FIG. The second embodiment further prevents the peripheral device from being heated by the heat radiated from the heating unit in the first embodiment. In the second embodiment, the same components as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 5, the decoloring apparatus 50 that is the image decoloring apparatus of the second embodiment includes an endothermic guard 51 that is a heat storage unit. The endothermic guard 51 is located at a position that shields between the decoloring section 14 and the sensor 13 and surrounds a part of the periphery of the decoloring section 14 on the sensor 13 side. The heat absorption guard 51 is formed, for example, by encapsulating a heat storage material 51b in the hollow interior of a copper plate 51a. As the heat storage material 51b, for example, sodium acetate having a melting point that maintains a temperature lower than the absolute maximum rated temperature of the sensor 13 (temperature t1) is used.

  The decoloring unit 14 radiates heat to the surroundings during the decoloring operation. The heat absorption guard 51 around the decoloring part 14 absorbs and stores heat radiated from the decoloring part 14 from the copper plate 51a to the heat storage material 51b. The endothermic guard 51 cools the temperature of the space between the color erasing unit 14 in the color erasing device 50 and the sensor 13 to a temperature lower than the absolute maximum rated temperature of the sensor 13 (temperature t1). Although the erasing unit 14 radiates heat, the sensor 13 maintains the absolute maximum rated temperature or less even during the continuous erasing operation.

  According to the second embodiment, similarly to the first embodiment, the heat of the sheet P heated by the decoloring section 14 is absorbed by the heat storage material 40 and the sheet P is cooled before reaching the sensor 13. To do. Further, the heat radiated from the decoloring unit 14 is absorbed by the heat absorption guard 51 to cool the air between the decoloring unit 14 and the sensor 13. During the decoloring operation, the temperature of the sensor 13 is more reliably maintained below the absolute maximum rated temperature, and the reading accuracy of the sheet P by the sensor 13 is maintained better. According to the reading result of the sensor 13, the decoloring device 50 can more reliably classify the reusable sheet P.

  In the embodiment described above, the heat storage unit that absorbs the heat of the recording medium that has passed through the heating unit is disposed in the cooling guide of the transport unit, but the heat storage unit may be disposed in the transport roller of the transport unit. For example, the recording medium may be nipped and conveyed by a rubber roller and a metal roller in which a heat storage material is sealed in the hollow, and the recording medium may be cooled to prevent the sensor from being heated. Further, the peripheral device is not limited to a sensor that reads a recording medium. Specific examples include a CPU board or system board, which is a processor board, a temperature sensor, a jam detection sensor, and a masking head used to indicate the number of times of decoloring.

  According to at least one embodiment described above, the image erasing apparatus includes a heat storage unit that absorbs heat generated by the heating unit. Regardless of the heat generated by the heating unit, the peripheral device is prevented from rising in temperature, the functional characteristics of the peripheral device are maintained well, and a good reuse sheet is obtained.

  Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 ... Decoloring apparatus 13 ... Sensor 14 ... Decoloring part 22 ... 3rd conveyance path 27a, 27b, 27c ... 1st thru | or 3rd conveyance roller 28a ... Upper cooling guide 28b ... Vertical cooling guide 28c ... Lower cooling guide 38 ... Guide Board 40 ... heat storage material

Claims (5)

A heating section for heating the recording medium to a temperature equal to or higher than the decoloring temperature of the colorant;
A transport unit that transports the recording medium that has passed through the heating unit;
Peripheral devices around the heating unit;
An image erasing apparatus comprising: a heat storage unit that absorbs heat reaching the peripheral device from the heating unit.   The image erasing apparatus according to claim 1, wherein the peripheral device has an absolute maximum rated temperature, and the heat storage unit holds the peripheral device at or below the absolute maximum rated temperature.   The image according to claim 1, wherein the transport unit transports the recording medium toward the peripheral device, and the heat storage unit absorbs heat of the recording medium via the transport unit. Erasing device.   4. The image erasing apparatus according to claim 1, wherein the heat storage unit is located at a position that shields between the heating unit and the peripheral device. 5.   The image erasing apparatus according to claim 1, wherein the peripheral device is a reading unit that reads the recording medium that has passed through the heating unit.

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