Exemplary embodiments described herein relate to a decolorizing device for decolorizing an image formed on a sheet by an image forming apparatus and accumulating the sheet from which the image has been decolorized, and also relate to a method for controlling the decolorizing device.
More sheets are consumed as the amount of various kinds of information increases. On the other hand, sheets are recycled in order to save the resource of sheets. For example, in recycling of sheets, used sheets having image information thereon made of toners and the like are processed using a large amount of bleaching agent and water, and thus recycled sheets are manufactured. Therefore, the recycling of sheets brings about the increase in the cost of recycles sheets, which diminishes the cost effectiveness and may incur new environment pollution resulting from treatment of waste water used during regeneration of used sheets.
In view of the above circumstances, a technique has been recently developed to greatly reduce the amount of actual use of sheets. According to this technique, erasable image forming material made of resin, pigment, color fixing agent, erasing agent, and the like is used to form an image on a sheet. This formed image is decolorized from the sheet by an image decolorizing device, and a white sheet is obtained. This white sheet from which the image has been decolorized is reused multiple times. According to this technique, the overall cost relating to reuse of sheets can be reduced.
For example, an image forming apparatus having an image decolorizing function for decolorizing color of image forming material by heating a sheet and capable of preventing misuse of a reused sheet has been known.
The above-described image forming apparatus has not only the image forming function but also the decolorizing function for decolorizing an image by heat. In addition, a detecting sensor is used to detect whether a mark indicating reusable sheet is attached to a sheet or not. Therefore, even when a user stacks both of reusable sheets and nonreusable sheets on a sheet feed tray in a mixed manner, the image forming apparatus can distinguish the reusable sheets. That is, the image forming apparatus performs image decolorizing processing on sheets attached with the mark indicating reusable sheet, and does not perform image decolorizing processing on sheets without the mark.
However, in the above-described image forming apparatus having the decolorizing device, if the decolorizing device is feeding sheets placed at an insertion opening in order to perform decolorizing processing on previously-inserted sheets when the user tries to perform decolorizing processing, the user is unable to insert sheets even though the user tries to feed sheets to perform new decolorizing processing on the sheets. In other words, in the case where the image forming apparatus has only one stacker for stacking sheets which are to be subjected to decolorizing processing, the uppermost sheet of stacked sheets is fed into the image forming apparatus while decolorizing processing is performed. Therefore, during the feeding operation, the user is unable to place sheets on the stackers. In addition, in the case where the placed sheets are fed in order from a feeding opening, there is a problem in that only the upper portion of the placed sheets are always reused repeatedly, resulting in low recycling efficiency. Still more, since sheets processed by the decolorizing device are already-used sheets, the sheets could be curled. When the sheets are curled, there is a possibility that the sheets are jammed during feeding operation and the processing cannot be carried out smoothly.
In general, according to one embodiment, there is provided a decolorizing device including: a first stacker to stack sheets to be decolorized images on the sheets; a second stacker arranged adjacent to the first stacker, wherein the sheets stacked on the first stacker is kept waiting on the second stacker in order to be decolorized the images; a pressing unit to urge the sheets stacked on the second stacker downward and keep the sheets stacked on the second stacker flat; an image decolorizing unit to decolorize the images on the sheets; and a sheet feed unit positioned on an upper surface of the pressing unit to convey the sheet pressed on the pressing unit from the second stacker to the image decolorizing unit.
The best embodiment of the decolorizing device will be hereinafter described in detail with reference to the attached drawings.
According to the present embodiment, a sheet transfer unit 101 is arranged with two stackers 200 and 201 for stacking sheets, and a partition wall 202 is arranged between the two stackers. This structure allows a user to add sheets P to the first stacker 200, even while sheets P are being fed from the second stacker 201 in order to be subjected to decolorizing processing. Further, a pressing unit 203 is arranged on the upper surface of the second stacker 201. Even when a reused sheet P is curled, the pressing unit 203 is urged upward by the sheet P, so that the sheet is kept flat.
The decolorizing device 100 includes a sheet transfer unit 101, a sheet feed roller 102, a first judging unit 103, a switching gate unit 104, a first nonreusable sheet stacker 105, an image decolorizing unit 106, a second judging unit 107, a second nonreusable sheet stacker 108, a both sides usable sheet stacker 109, a one-side usable sheet stacker 110, and a display 111.
The user can stack sheets P to be reused on the first stacker 200 exposed to the outside of the decolorizing device 100. When all the sheets P on the second stacker 201 are transferred toward the image decolorizing unit 106, and the second stacker 201 becomes empty. At this occasion, the sheet transfer unit 101 can convey the bundle of sheets P on the first stacker 200 from the first stacker 200 to the second stacker 201.
The sheet feed roller 102 is constituted by a pair of driving roller and a driven roller. The sheet feed roller 102 feeds sheets fed from the sheet transfer unit 101 in order to have the sheets subjected to decolorizing processing.
The first judging unit 103 is constituted by an ultrasonic sensor 103a and a sheet thickness sensor 103b. Before a sheet P is subjected to decolorizing processing, the first judging unit 103 judges whether the image on the sheet P can be decolorized.
The ultrasonic sensor 103a emits an ultrasonic wave to detect multi-feeding. The ultrasonic sensor 103a detects an air layer between sheets when multiple overlapped sheets P are conveyed. In other words, an ultrasonic wave is emitted, and when an air layer is detected, this means that multiple sheets P are overlapping.
The sheet thickness sensor 103b detects the thickness of a sheet P. For example, the sheet thickness sensor 103b detects multi-feeding, a folded sheet P, a torn sheet P, a staple, and the like. In other words, a sheet P having an abnormal thickness is inappropriate for reuse, and accordingly, the sheet thickness sensor 103b judges that the sheet P is nonreusable.
The switching gate unit 104 switches the conveying direction of the fed sheet P. For example, when the first judging unit 103 judges that a sheet is reusable, the switching gate unit 104 chooses a conveying path to image decolorizing processing. On the other hand, when the first judging unit 103 judges that a sheet is nonreusable, the switching gate unit 104 chooses a conveying path to the first nonreusable sheet stacker 105.
The first nonreusable sheet stacker 105 stacks and stores the sheet P that is judged to be nonreusable by the first judging unit 103.
The image decolorizing unit 106 is constituted by a pair of rollers. The pair of rollers generates heat having a temperature equal to or more than a certain temperature. A sheet having an image formed with erasable image forming material is passed between the pair of heated rollers, so that the image is decolorized from the sheet P, and the sheet P returns back to white. Since the image decolorizing unit 106 is constituted by the pair of rollers, the images on both sides of the sheet P can be decolorized.
The second judging unit 107 is constituted by a pair of two-dimensional CCD scanners. The CCD scanners scan both sides of a sheet P to judge whether the image has been decolorized without fault. In other words, the second judging unit 107 judges whether there is any remaining image that has not yet been decolorized by the image decolorizing unit 106. In addition, the second judging unit 107 can detect wrinkle, tear, and the like on the sheet P, which cannot be detected by the sheet thickness sensor 103b. The second judging unit 107 is not limited to the pair of two-dimensional CCD scanners, but may be one-dimensional scanners, CCD sensors, and the like.
A sheet P that cannot be decolorized, a torn sheet P, and the like are judged to be nonreusable by the second judging unit 107. The second nonreusable sheet stacker 108 stacks and stores the sheet P that is judged to be nonreusable by the second judging unit 107.
The both sides usable sheet stacker 109 stacks and stores the sheet P, both sides of which are judged to be reusable by the second judging unit 107.
The one-side usable sheet stacker 110 stacks and stores the sheet P, one side of which is judged to be reusable by the second judging unit 107. In the present embodiment, the upper sides of the sheets P stacked on the one-side usable sheet stacker 110 are reusable sides. In other words, the upper sides are white. Alternatively, the sheets P may be stacked such that the white side of the sheet P is oriented downward.
The display 111 indicates that sheets are transferred when the sheet transfer unit 101 transfers sheets. For example, the display 111 turns on an LED to indicate that transfer processing is performed. The display 111 is not limited to this form. Alternatively, the display 111 may use a display and the like to indicate that the transfer processing is performed.
Subsequently, the sheet transfer unit 101 will be explained in detail. The sheet transfer unit 101 includes the first stacker 200, the second stacker 201, the partition wall 202, and the pressing unit 203.
In the sheet transfer unit 101 as shown in
The first stacker 200 includes an upper plate 200a and a lower plate 200b. A solenoid 204 moves the upper plate 200a upward and downward via a link mechanism. It is only the first stacker 200 that is constituted by the upper plate 200a and the lower plate 200b and in which the upper plate 200a moves upward and downward. The second stacker 201 is constituted by one plate (tray). Before a sheet P is handed over, the upper plate 200a is at the same height as the upper surface of the second stacker 201 or at a height higher than the second stacker 201. When the sheet P is handed over to the second stacker 201, the upper plate 200a descends to a height lower than the upper surface of the second stacker 201. After the sheet P has been handed over, and the first stacker 200 returns back to its original position, the upper plate 200a returns back to the height at which the upper plate 200a was located before the sheet P was handed over.
The second stacker 201 is arranged adjacent to the first stacker 200 in the decolorizing device 100. The second stacker 201 is a tray for stacking the sheets P conveyed from the first stacker 200. The uppermost sheet P in the bundle of sheets P stacked on the second stacker 201 is fed one by one by a pickup roller 302a toward the first judging unit 103. The second stacker 201 ascends and descends within the range of the sheet feed position with respect to the position adjacent to the first stacker 200. As the uppermost sheet P is fed one by one, the second stacker 201 ascends to such a position that the uppermost sheet P can be smoothly picked up.
The partition wall 202 is installed between the first stacker 200 and the second stacker 201, and opens and closes. The partition wall 202 is closed in a normal state. When the sheet P is transferred from the first stacker 200 to the second stacker 201, the partition wall 202 opens. When the transfer of the sheet P is finished, and the first stacker 200 returns back to its original position (outside of the partition wall 202), the partition wall 202 closes.
The pressing unit 203 is positioned on the upper surface of the second stacker 201. Even when a sheet P to be reused is curled, the pressing unit 203 is positioned on the upper surface of the sheet P, so that the sheet P can be kept flat.
Hereinafter explained in detail is how a sheet P is transferred from the first stacker 200 to the second stacker 201.
When the solenoid 204 is activated, the upper plate 200a of the first stacker 200 descends. Since the upper plate 200a is always urged upward by a spring, the upper plate 200a ascends back to its original position when the operation of the solenoid 204 is deactivated. A belt 205c is stretched over a pulley 205b and a motor shaft 205a of the motor 205. The belt 205c rotates, which cause the first stacker 200 coupled with the belt 205c to move to right and left. The first stacker 200 can come into proximity to the second stacker 201, and when the partition wall 202 is open, a portion of the first stacker 200 can enter into the second stacker 201.
For the second stacker 201, a motor 206 is arranged as a mechanism for moving the bundle of sheets P upward and lowering the second stacker 201 back to its original position when the second stacker 201 runs out of sheet P. A belt 206c is placed over a pulley 206b and a motor shaft 206a of the motor 206. The belt 206c rotates, which cause the second stacker 201 coupled with the belt 206c to move upward and downward. In
A motor 207 is used as an open/close mechanism of the partition wall 202. When the motor 207 rotates, the partition wall 202 coupled with the motor 207 via the rack moves upward and downward.
The series of operations of sheet transfer from the first stacker 200 to the second stacker 201 has been hereinabove explained. When the second stacker 201 runs out of sheet P again, and it is necessary to transfer sheets P from the first stacker 200, the flow from
In the present embodiment, the upper plate 200a of the first stacker 200 moves upward and downward and to right and left, thereby handing over the sheets P from the first stacker 200 to the second stacker 201. Alternatively, the second stacker 201 may move upward and downward when the sheets P are handed over. In other words, after the first stacker 200 and the second stacker 201 engage with each other in
Subsequently, the pressing unit 203 will be explained.
The pressing face 300 for pressing the sheets is arranged to keep the sheets flat even when the sheets P are curled. The flat face of the pressing face 300 that is in contact with the sheets P is made of a low-frictional material. A low-frictional material such as mylar, i.e., a sheet made of resin, may be attached.
The spring 301 is arranged at an end of the pressing face 300, and urges the pressing face 300 in the downward direction of the drawings. Three or four springs 301 are preferably arranged.
The pickup unit 302 includes an arm 302c, a spindle 302b rotatably supporting the arm 302c, and a pickup roller 302a attached to an end of the arm 302c. The pickup unit 302 is urged downward by a spring. The pickup roller 302a picks up and feeds the sheets P with the contacting force and the rotational force exerted on the sheets P. The pickup roller 302a rotates about the spindle 302b.
The rear end of the arm 302c rotates, and the upper surface detecting sensor 303 detects the upper surface position of the sheets P by determining whether the rear end of the arm 302c has blocked a light passing portion of the sensor 303 or not. When the light passing portion of the upper surface detecting sensor 303 is blocked by the rear end of the arm 302c, the upper surface of the sheets P is in contact with the pressing face 300.
In
After the ascend of the second stacker 201 has stopped, the pickup unit 302 conveys the sheets P to processing of later stage. Since the pressing face 300 is made of a low-frictional material, the sheets P can be conveyed by the pickup unit 302 and the sheet feed roller 102.
The upper surface portion of the stacked sheets P is urged downward by the pressing unit 203, and the stacked sheets P are held by the second stacker 201 arranged below. Therefore, even when the sheets P are curled, the sheets P can be held flat. Since the pickup roller 302a is used to detect the upper surface of the sheets P, the pickup roller 302a can always feed the sheets P with a constant contacting force.
Subsequently, the series of movements of the sheet P in the decolorizing device 100 will be explained. In the present embodiment, there are five conveying paths of the sheets P. The first path is used when the first judging unit 103 judges that the sheet P is nonreusable, and the sheep P is stored to the first nonreusable sheet stacker 105 through this path. The second path is used when the second judging unit 107 judges that the sheet P is nonreusable, and the sheep P is stored to the second nonreusable sheet stacker 108 through this path. The third path is used when the second judging unit 107 judges that the sheet P is reusable, and the sheep P is stored to the both sides usable sheet stacker 109 through this path. The fourth path is used when the second judging unit 107 judges that the upper side of the sheet P is reusable, and the sheep P is stored to the one-side usable sheet stacker 110 through this path. The fifth path is used when the second judging unit 107 judges that the lower side of the sheet P is reusable, and the sheep P is stored to the one-side usable sheet stacker 110 through this path.
First, the first path will be explained.
Subsequently, the second path will be explained.
The second judging unit 107 judges that both sides of the sheet P are nonreusable, not only in the case where the images are formed with non-erasable image forming material, but also in the following cases: a note is written to the sheet P with a pen or pencil; a wrinkle occurs on the sheet P beyond repair; and the sheet P is torn.
Subsequently, the third path will be explained.
Subsequently, the fourth path will be explained.
Subsequently, the fifth path will be explained.
As shown in
The above-explained decolorizing device can improve the operability by allowing the user to add sheets P to the first stacker 200 even while the decolorizing device is carrying out the decolorizing processing. Further, the decolorizing device includes the pressing unit 203 above the second stacker 201. The pressing unit 203 keeps sheets P flat and provides the sheets P in a stable manner even when the sheets P are curled.
While certain embodiments have been described, those embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and apparatuses described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and apparatuses described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
Number | Date | Country | Kind |
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2010-038331 | Feb 2010 | JP | national |
2010-116009 | May 2010 | JP | national |
This application is based upon and claims the benefit of priority from: U.S. provisional patent application No. 61/226,639, filed on Jul. 17, 2009; and U.S. provisional patent application No. 61/226,626, filed on July 17, the entire contents of each of which are incorporated herein by reference. This application is also based upon and claims the benefit of priority from: Japanese Patent Application No. 2010-38331, filed on Feb. 24, 2010; and Japanese Patent Application No. 2010-116009, filed on May 20, 2010, the entire contents of each of which are incorporated herein by reference.
Number | Date | Country | |
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61226639 | Jul 2009 | US | |
61226626 | Jul 2009 | US |