JP2000344427A - Paper feeding system for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeding system for an image forming device properly deciding an unrecorded surface of a used paper formed with an image on one side and feeding the paper to an image forming part. SOLUTION: In an image forming device 100, a detection part 105 detects whether the upper surface (an A surface) of a used paper 103 fed from a paper feeding tray 104 on which the plural used papers 103 are placed is an image- unformed surface or an image-formed surface. On the basis of the detection result, the used paper 103 is directly fed to a first storage part 107, or is inverted in an inversion part 109 and fed to a second storage part 108. Thus, the used papers 103 are sequentially placed on the first storage part 107 and the second storage part 108 with the image-unformed surfaces (white surfaces) up. The used papers 103 are selectively sequentially fed to an image forming part 102 from the first storage part 107 and the second storage part 108 in the order of arrival, and an image is formed on the image-unformed surface of the used paper 103 in the image forming part 102.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding system for an image forming apparatus, and more particularly, to a non-recording side of an image when used paper having an image formed on one side thereof is disturbed. The present invention relates to a sheet feeding system of an image forming apparatus that appropriately determines and conveys an image to an image forming unit.

[0002]

2. Description of the Related Art Conventionally, in order to protect forest resources and to make effective use of resources, image forming apparatuses such as printers, copiers and facsimile machines use used paper on which an image is formed on one side. An image is formed on the other side on which no image is formed.

In this case, the operator of the image forming apparatus has
The used paper is set on the paper feed tray of the image forming apparatus so that the image forming surfaces of the used paper are aligned and an image is formed only on the white surface.

However, when aligning the image forming surfaces or setting the image forming apparatus on the paper feed tray of the image forming apparatus, a human error may occur in which some or all of the used paper is turned upside down. is there.

[0005] In such a case, the image of the original is overwritten on the surface of the used paper on which the image has already been formed. It is necessary to check whether the image is properly formed on the unused surface, and if it is overwritten, it is necessary to check the front and back sides of the used paper in the paper feed tray and perform image formation again, which is complicated. there were.

Therefore, various proposals have conventionally been made to solve this problem. For example, a paper feeding system of an image forming apparatus previously proposed by the present applicant (Japanese Unexamined Patent Application Publication No.
-69478). The paper feeding system of the image forming apparatus includes a paper determining mechanism that determines whether the surface to be copied or printed is unused white or has already been used. Specifically, it is configured as shown in FIG. 8, and includes a sheet feeding device 801 on which a plurality of used sheets 800 are placed, and a sheet determination for detecting whether the surface to be copied (that is, the back surface) is white. A mechanism 802, a paper reversing device 803 for reversing the front and back of the used paper 800, and a copying unit 804 are provided. Then, the paper feeding device 801 conveys the stored used paper 800 to the paper determination mechanism 802, and the paper determination mechanism 802 determines whether the surface of the used paper 800 to be copied is white and copies the used paper 800. If it is determined that the surface is white,
The used paper 800 is conveyed to the copying unit 804 as it is.
If the paper determination mechanism 802 determines that the copy side of the used paper 800 sent from the paper feeding device 801 is already printed, it sends the used paper 800 to the paper reversing device 803 and uses the used paper 800 in the paper reversing device 803. The finished paper 800 is conveyed to the copying unit 804 with its front and back reversed.

[0007] When the paper feeding system of the image forming apparatus is used, it is appropriately determined whether or not the copy surface of the used paper 800 is an unused surface. Thus, it is possible to reduce the complexity of the user such as checking the front and back of the used paper 800 and copying again.

However, in the paper feeding system of the image forming apparatus, the time required to send the used paper 800 from the paper determination mechanism 802 to the copying unit 804 via the paper reversing device 803 (that is, the time required for the used paper 800 having the wrong front and back sides). The transport time) is longer than the time to be sent directly from the paper determination mechanism 802 to the copy unit 804 (that is, the transport time of the used paper 800 whose front and back are correct). To paper reversing device 80
3, the speed is controlled by the transport time sent to the copying unit 804,
There is a demand for an improvement in copying speed.

As a technique for improving the image recording speed, an image forming apparatus described in Japanese Patent Application Laid-Open No. Hei 7-52482 and Japanese Patent Application Laid-Open No. Hei 5-5115 previously proposed by the present applicant have been proposed.
There is an image forming sheet processing apparatus described in Japanese Patent Application Publication No. 0-205.

For example, the image forming apparatus described in Japanese Patent Application Laid-Open No. 7-52482 is specifically configured as shown in FIG. 9, and the surface of the used paper 900 to be copied (that is, the back surface) is Blank paper detection unit 901 for detecting whether the color is white
And a reversing storage unit 902 for reversing the used paper 900 and storing one reversed used paper 900. When the blank sheet detection unit 901 determines that the surface of the used paper 900 to be copied is white, the image forming apparatus conveys the used paper 900 through the conveyance route shown in FIG. If the used paper 900 is sent to the unit 903 and determined to be printed on the surface to be copied by the blank paper detection unit 901 and the used paper 900 is not stored in the reverse storage unit 902, the used paper 900 is displayed in FIG. The reverse transport route shown in FIG.
And store it temporarily after it is turned over.

On the other hand, if the blank paper detecting unit 901 determines that the image is printed on the surface to be copied and the used paper 900 is stored in the reverse storage unit 902, the image forming apparatus stores the used paper. The used paper 900 is sent from the reversing storage unit 902 to the image recording unit 903, and the used paper 900 determined to be printed on the surface to be subsequently copied is used.
Is sent to the reversing storage unit 902, and is temporarily stored after being turned upside down.

According to such a procedure, the used paper 900
When the front and back are wrong, the used paper 900 can be supplied from the reverse storage unit 902 from the second sheet.
Compared with the paper feeding system described in Japanese Patent Application Laid-Open No. 7-69478, the tact time required to convey the wrong used paper 900 on the front and back can be substantially shortened, and as a result, a reduction in the copying speed can be suppressed. be able to.

However, in order to maintain the same copying speed as that of a conventional copying machine, it is necessary to perform the processing time of the reverse transport route within the processing time of the transport route. Although the above conditions can be achieved with a low-speed copying machine, it is impossible for a high-speed copying machine to keep the processing time of the transport route within the processing time of the transport route. Cannot be applied.

In view of the above, the applicant of the present invention has proposed an insertion slot for inserting an image-formed sheet bundle into the apparatus main body and a paper bundle while gradually aligning the ends of the sheet bundle inserted from the insertion port. Inclined surface for feeding the sheet to the apparatus main body, sheet edge aligning means for aligning the ends of the sheet bundle, separating and conveying means for separating and conveying the sheets one by one from the sheet bundle, and an image-formed surface for the conveyed sheet. And an unused surface, and a conveying device for conveying a sheet having an unused surface to the image forming apparatus. See JP-A-5-51150).

The image-formed sheet processing apparatus is specifically configured as shown in FIG.
Reflective photosensor 100 for detecting a white surface of 000
1, 1002, and a conveyance route and a conveyance route for sending only the white surface to the image forming apparatus 1003, and a used paper 1000 on which images are already formed on both surfaces of the image forming apparatus 1003.
4 is provided, and the image-formed paper processing apparatus 1005 is attached to a paper feeding unit of the image forming apparatus 1003.

The transport route is a route for sending the used paper 1000 to the image forming apparatus 1003 as it is when it is determined that the surface to be copied is white. The transport route is a route where the surface to be copied is printed. If it is determined that the used sheet 1000 is turned over on the switchback conveyance path and sent to the image forming apparatus 1003.

That is, after the used paper 1000 is turned upside down in the image-formed paper processing apparatus 4, the image forming apparatus 1
At 003, copying is performed.

Therefore, since the front and back of the used paper 1000 are aligned only by the image-formed paper processing apparatus 1005, the used paper 100
It is possible to perform front-to-back printing of 0 and transport to the image forming apparatus 1003. As a result, the used paper 1000 having the same front and back sides is always supplied to the paper feeding unit of the image forming apparatus 1003, and the copying speed does not decrease even when the present invention is applied to the high-speed image forming apparatus 1003.

[0019]

However, in the image-formed sheet processing apparatus 1005 described in Japanese Patent Application Laid-Open No. 5-51150, the image forming apparatus 1003 is used when continuous copying is performed on the used sheet 1000. Since there is only one used sheet 1000 in the sheet feeding section of the second sheet, it is necessary to simultaneously perform the front and back determination and conveyance by the image-formed sheet processing apparatus 1005 and copying by the image forming apparatus 1003 from the second sheet. If the processing speed of the image-formed paper processing apparatus 1005 is lower than the copying speed, the copying speed is reduced.

Conversely, in order not to lower the copying speed,
It is necessary to increase the processing speed of the image-formed paper processing apparatus 1005, and there is a problem that sufficient time cannot be secured for the front / back determination by the reflection type photo sensors 1001 and 1002.

On the other hand, the used paper 1000 supplied from the image-formed paper processing apparatus 1005 is transferred to the image forming apparatus 100.
It is conceivable that a plurality of sheets are stacked on the paper feed tray 3 so as not to lower the copying speed even for continuous copying. However, in a general copying machine, the used paper 1000 stacked on the paper feed tray is considered. To be transported sequentially from the top layer,
During copying, the used paper 1000 transported from the image-formed paper processing apparatus 1004 cannot be stacked on the paper feed tray. As a result, only when the image forming apparatus 1003 is on standby, the used paper 1000 can be put on the paper feed tray and stacked, and the copying can be actually performed after the used paper 1000 is set in the image forming processing apparatus 1004. There will be a time lag before it becomes true.

As a result, when the used paper 1000 runs out of the paper feed tray during continuous copying, a certain amount of waiting time is required after the used paper 1000 is supplied to the image-formed paper processing apparatus 1005. There is a possibility that the user may not be able to copy.

Therefore, according to the first aspect of the present invention, one surface of the used paper sent out from the mounting portion on which a plurality of used papers are mounted is used as a detection surface, and the detection surface is used for forming an unimaged image. The detection unit detects whether the surface is a surface or an image-formed surface,
Based on the detection result, the used paper sent from the placement unit is directly conveyed to the first storage unit or, after being reversed by the reversing unit, is conveyed to the second storage unit for use. The non-image-formed surface or the already-image-formed surface of the used paper is aligned and sequentially placed on the first storage unit and the second storage unit, and the used paper is selectively selected from the first storage unit and the second storage unit. Are sequentially transported to the image forming unit in the order in which they are placed first, and the image forming unit forms an image on the non-image forming surface of the used paper, so that the used paper is Even when the image-formed surface is not aligned, the image forming unit appropriately determines whether the image-formed surface is an unimage-formed surface or an already-image-formed surface. Are stored in the first and second storage units, and the used paper is transported from these storage units to the image forming unit in the order of placement. It is possible to form an image on a used paper continuously from the time when the used paper is first placed on the mounting portion without the user checking the front and back of the used paper or performing the copying / printing again, and It is another object of the present invention to provide a sheet feeding system for an image forming apparatus that can be applied to a high-speed image forming apparatus.

According to a second aspect of the present invention, the image forming surface of the used paper sent from the mounting portion on which a plurality of used papers are mounted is an unimaged surface or an already formed image surface. Is detected by the detection unit, and based on the detection result, the used paper sent from the mounting unit is directly conveyed to the storage unit, or, after being inverted by the reversing unit, is conveyed to the storage unit. The non-image forming surface or the already formed image forming surface of the used paper is arranged and sequentially placed on the storage unit, and the used paper is sequentially transported from the storage unit to the image forming unit in the order in which the used paper is placed first, thereby forming the image. By forming an image on the non-image forming surface of the used paper by the unit, even when the used paper is mounted on the mounting unit in a state where the non-image forming surface and the already formed image forming surface are not aligned. The image forming unit appropriately determines whether the surface on which an image is to be formed is an unimaged surface or an already-imaged surface. , And stored in one storage unit by aligning unimaged surface, with a compact and inexpensive structure,
The used paper is transported from the storage unit to the image forming unit in the loading order, and the used paper is first loaded on the mounting unit without the user confirming the front and back of the used paper or performing the copying / printing again. It is an object of the present invention to provide a paper feeding system of an image forming apparatus that can continuously form an image on a used sheet from the time when the sheet is placed and is applicable to a high-speed image forming apparatus.

According to a third aspect of the present invention, it is determined whether the surface opposite to the surface detected by the detecting unit of the used paper sent from the placing unit is an unimaged surface or an already-imaged surface. When the detection unit 2 detects that both of the detection units and the second detection unit are the image-formed surfaces, the used paper is sequentially placed on both of the used papers whose both surfaces are the image-formed surfaces. By transporting and placing the paper on the paper output storage unit, it is possible to prevent erroneous image formation on an already-imaged surface when used paper placed on the loading unit has already been image-formed on both sides. Accordingly, it is an object of the present invention to provide a sheet feeding system of an image forming apparatus which can form an image on a non-image forming surface without fail and which is more usable.

According to a fourth aspect of the present invention, the used paper is placed on the placement portion with the image-formed surface facing up, and the surface opposite to the image-formed surface is detected based on the detection result of the detection portion. Is the first storage unit, the second storage unit is in the state where
By transporting the paper to the storage unit or the storage unit, when setting used paper on the loading unit, it is possible to set the used paper while checking the image-formed surface of the used paper. In the case where the sheet storage unit is provided, it is possible to easily recognize the placement unit on which the used paper is set and the placement unit on which the unused paper is set, so that the usability is further improved. It is an object of the present invention to provide a paper feed system for an image forming apparatus.

According to a fifth aspect of the present invention, the detecting section is configured such that, of the used sheets placed on the placing section, one side of the used sheet to be sent out next is set as a detecting surface, and By detecting whether the surface is an unimaged surface or an already-imaged surface, the surface of the used paper on which the image is to be formed by the image forming unit in a state where the used paper is set on the mounting portion. Appropriately determine whether the surface is an unimaged surface or an already-imaged surface,
It is an object of the present invention to provide a sheet feeding system of an image forming apparatus that is more usable.

According to a sixth aspect of the present invention, there is provided a receiving section, a detecting section,
The first storage unit, the reversing unit, the second storage unit, or the storage unit, or the second detection unit and the paper discharge storage unit, which can be put in and taken out of the image forming apparatus or can be attached and detached. By storing the paper in the paper feed tray, the paper feed system can be applied to the existing image forming apparatus, and the user can easily and quickly form the image using the used paper without adding complexity to the user. It is an object of the present invention to provide a sheet feeding system of an image forming apparatus that can perform the sheet feeding.

[0029]

According to a first aspect of the present invention, there is provided a sheet feeding system for an image forming apparatus, wherein a used sheet is conveyed from a sheet feeding system to an image forming section, and the used sheet is converted to the used sheet by the image forming section. In a paper feeding system of an image forming apparatus for performing image formation, a mounting portion on which a plurality of the used papers are mounted and a surface on one side of the used paper sent from the mounting portion are detected. A detection unit for detecting whether the detection surface is an unimaged surface or an already-imaged surface, and aligning the surface on which the used paper directly conveyed from the placement unit is conveyed. A first storage unit for sequentially stacking and storing, a reversing unit for reversing the front and back of the used paper sent from the placement unit, and the used paper conveyed by being reversed and conveyed by the reversing unit. Align the incoming surfaces and stack them sequentially Comprising a second storage unit for tubes, a,
Based on the detection result of the detection unit, the used paper sent from the placement unit is directly conveyed to the first storage unit, or after being inverted by the reversing unit,
To the storage unit of the used paper, the unimaged surface or the already-imaged surface of the used paper is aligned and sequentially placed on the first storage unit and the second storage unit, and the first storage unit And the second
The above object is achieved by selectively transporting the used paper sheets sequentially from the storage unit to the image forming unit in the order in which they are placed first.

According to the above arrangement, whether one of the surfaces of the used paper sent out from the mounting portion on which a plurality of used papers are mounted is a detection surface and the detection surface is a non-image-formed surface or not. The detection unit detects whether the surface is an image-formed surface, and based on the detection result, the used paper sent from the placement unit is directly conveyed to the first storage unit or inverted by the reversing unit. After that, the sheet is transported to the second storage unit, and the unimaged surface or the already-imaged surface of the used paper is aligned and sequentially placed on the first storage unit and the second storage unit, and the first storage is performed. Since the used paper is selectively conveyed to the image forming unit in the order in which the used paper is placed first from the second storage unit and the second storage unit, and the image forming unit forms an image on the non-image forming surface of the used paper. When the used paper is placed on the loading section with the unimaged surface and the imaged surface not aligned It is possible to appropriately determine whether a surface on which an image is to be formed by the image forming unit is a non-image forming surface or a previously formed image forming surface, and align the non-image forming surfaces in the first and second storage units. The used paper can be conveyed from the storage unit to the image forming unit in the order in which they are placed, and the user can check the front and back of the used paper or repeat copying / printing, thereby improving usability. Also, it is possible to continuously form an image on the used paper from the time when the used paper is first placed on the mounting portion,
Further, the present invention can be applied to a high-speed image forming apparatus.

According to a second aspect of the present invention, there is provided the image forming apparatus, wherein the used paper is conveyed from the paper feeding system to the image forming unit, and the image forming unit forms an image on the used paper. In the paper feeding system of the apparatus, a mounting portion on which a plurality of the used papers are mounted, and an image forming surface of the used paper sent from the mounting portion is an unimaged surface or an already formed image. A detection unit that detects whether the surface is a forming surface;
A storage unit for storing the conveyed used paper sheets sequentially stacked with the conveyed surfaces aligned and storing the used paper sheets, and conveying the used paper sheets sent from the placement unit to the storage unit by turning over the front and back of the used paper sheets And a reversing unit that performs, based on the detection result of the detection unit, directly transports the used paper sent from the placement unit to the storage unit, or after the reversing unit reverses the used paper. Transported to the storage unit, the unprinted surface or the already-imaged surface of the used paper is aligned and placed on the storage unit sequentially, and the used paper is placed first from the storage unit. The above object is achieved by sequentially transporting the toner to the image forming unit in order.

According to the above configuration, it is determined whether the image forming surface of the used paper sent out from the mounting portion on which the plurality of used papers are mounted is the non-image forming surface or the already formed image forming surface. Based on the detection result, the detection unit detects and transports the used paper sent from the loading unit directly to the storage unit, or reverses it in the reversing unit and transports it to the storage unit. The non-image forming surface of the used paper or the already formed image forming surface is aligned and sequentially placed on the storage unit, and the used paper is sequentially transported from the storage unit to the image forming unit in the order in which the used paper is placed first. Since an image is formed on the non-image forming surface of the used paper, even when the used paper is placed on the mounting portion in a state where the non-image forming surface and the already formed image forming surface are not aligned, the image forming is performed. The unit appropriately determines whether the surface on which an image is to be formed is a non-image-formed surface or an already-image-formed surface. Surfaces can be stored in a single storage unit with a uniform surface, and a small and inexpensive configuration can be achieved. In addition, used paper can be transported from the storage unit to the image forming unit in the order in which they are placed. This eliminates the need to check the front and back of the used paper and repeat copying / printing, etc., thereby improving the usability. In addition, the used paper is continuously used from the time when the used paper is first placed on the loading section. Can form images on finished paper,
Further, the present invention can be applied to a high-speed image forming apparatus.

In each of the above cases, for example, as set forth in claim 3, the sheet feeding system of the image forming apparatus includes:
A second detection unit that detects whether the surface of the used paper sent from the placement unit opposite to the surface detected by the detection unit is a non-image-formed surface or an already-image-formed surface; A paper output storage unit that sequentially places the used papers on both sides of which are already image-formed surfaces, and further detects that both the detection unit and the second detection unit are already-image-formed surfaces; The used paper may be conveyed and placed on the paper discharge storage unit.

According to the above arrangement, whether the surface opposite to the surface detected by the detecting unit of the used paper sent from the mounting unit is the non-image-formed surface or the already-image-formed surface is determined by the second method. When the detection unit detects that both the detection unit and the second detection unit are the image-formed surfaces, the used paper is sequentially discharged with the used paper having both surfaces already formed. Since the paper is conveyed to the storage unit and placed thereon, when the used paper placed on the placement unit has already been image-formed on both sides, it is possible to prevent the image from being erroneously formed on the image-formed surface, An image can be surely formed on the non-image forming surface, and the usability of the sheet feeding system of the image forming apparatus can be further improved.

Further, for example, in the paper feeding system of the image forming apparatus, the used paper is placed on the loading section with the image-formed surface up, and the detection is performed. The first storage unit, the second storage unit, or the storage unit, based on the detection result of the copy unit, in a state in which a surface opposite to the image-formed surface is an image formation surface in the image formation unit. May be conveyed to a unit.

According to the above configuration, the used paper is placed on the loading portion with the image-formed surface facing up, and based on the detection result of the detection portion, the surface opposite to the image-formed surface is imaged. The sheet is conveyed to the first storage section, the second storage section, or the storage section in a state where the used sheet is used as an image forming surface in the forming section. When the printer can be set while checking the image-formed surface and has a plurality of loading sections, the loading section where the used paper is set and the loading section where the unused paper is set It is possible to easily identify the copy unit and the usability of the sheet feeding system of the image forming apparatus can be further improved.

Further, for example, as set forth in claim 5, the detecting section is provided on one side of a used sheet to be sent out next among the used sheets placed on the placing section. May be used as a detection surface to detect whether the detection surface is a non-image-formed surface or an already-image-formed surface.

According to the above configuration, the detecting unit is configured to set the one surface of the used paper to be sent out next among the used papers placed on the mounting unit as the detection surface and to set the detection surface to the unimaged state. Since it is to be detected whether the surface is a forming surface or a previously formed image forming surface, in a state where the used paper is set on the mounting portion, the surface of the used paper on which the image is formed by the image forming portion is an unimaged image. It is possible to appropriately determine whether the surface is a formed surface or an image-formed surface, and the usability of the paper feeding system of the image forming apparatus can be further improved.

Further, for example, as set forth in claim 6, the placement section, the detection section, the first storage section, the reversing section, the second storage section, or the storage section, The second detection unit and the paper discharge storage unit are removable from the image forming apparatus or detachable from the image forming apparatus.
It may be stored in a plurality of paper feed trays.

According to the above configuration, the placing section, the detecting section, the first
Storage unit, reversing unit, second storage unit, or storage unit,
Alternatively, the second detection unit and the paper discharge storage unit are housed in a single paper tray that can be taken in and out of the image forming apparatus or that is detachable. By applying the above, image formation can be simply and easily performed at high speed and appropriately using used paper without complicating the user.

[0041]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 and 2 are diagrams showing a first embodiment of a paper feeding system of an image forming apparatus according to the present invention. It is.

FIG. 1 shows an image forming apparatus 100 to which a first embodiment of a sheet feeding system for an image forming apparatus according to the present invention is applied.
FIG.

In FIG. 1, an image forming apparatus 100 includes a paper feeding system unit 101 and an image forming unit 102, and the used image forming unit 102 is used and conveyed from the paper feeding system unit 101 by an electrophotographic recording method. An image is recorded on the recording surface of the sheet 103.

The paper feeding system unit 101 includes a paper feeding tray (loading unit) 104, a detecting unit 105, a separating unit 106, a first storing unit 107, a second storing unit 108, a reversing unit 109, and the like. A plurality of used papers 103 are stored in the paper feed tray 104.

Used paper 103 in paper feed tray 104
Is conveyed one by one to the detection unit 105 by the conveyance roller 110 and the conveyance roller 111, and the detection unit 105 forms a copy surface (FIG. 1) which is one surface of the used paper 103 on which the image forming unit 102 forms an image. Is determined as a detection surface, and whether or not the detection surface is white (non-image recording surface) is determined.
Output to a control unit not shown. The detection unit 105 uses, for example, a reflection-type photo sensor or a reflection-type line sensor. The reflection-type photo sensor scans the conveyed used paper 103 in two directions to generate a reflection image. The pattern line sensor measures the entire surface A of the used paper 103 by performing main scanning and sub-scanning on the conveyed used paper 103. The control unit (not shown) determines whether the surface A of the used paper 103 is a white surface or an image-formed surface (image-formed surface) by the reflection type photosensor or the reflection type line sensor as the detection unit 105. Is compared with a threshold level previously evaluated for white (unused) paper. The surface of the used paper 103 indicated by a double-headed arrow B in FIG.
The back side with respect to the A side of No. 03 is shown.

As shown in FIG. 2, the separation unit 106 includes a switching plate 112, a storage side conveyance path 113, and a reversing side conveyance path 1
2 and transport rollers 115, 116, etc., and the switching plate 112, as shown by a double-headed arrow in FIG.
14, the used paper 103 conveyed by the conveyance roller 111 is switched between the storage side conveyance path 113 side and the reversal side conveyance path 114 side to perform a switching operation.

The storage-side transport path 113 is used for the used paper 103
Transport path to the first storage unit 107 in FIG.
The reversing-side transport path 114 is a transport path that transports the used paper 103 to the reversing unit 109 in FIG.

The transport roller 115 is connected to the switching plate 112
The used paper 103 switched to the storage-side transport path 113 by the first storage unit 107 is moved to the first storage unit 107 on the storage-side transport path 113.
Transport to

The transport roller 116 is connected to the switching plate 112
Thus, the used paper 103 switched to the reversing side conveyance path 114 is conveyed to the reversing unit 109 on the reversing side conveyance path 114.

That is, when the detection unit 105 detects that the detection surface of the used paper 103 is white, the control unit switches the switching plate 112 to the reversing-side conveyance path 114 and shuts off the reversing-side conveyance path 114. Then, the used paper 103 is transported to the first storage unit 107 by the transport rollers 115 through the storage-side transport path 113. The detecting unit 1 also determines that the detection surface of the used paper 103 is a used surface (image-formed surface).
05, the control unit switches the switching plate 112 to the storage side conveyance path 113 side, shuts off the storage side conveyance path 113, and transfers the used paper 103 to the reversing unit 109 by the conveyance roller 116 through the reversal side conveyance path 114. Transport.

In the above example, the separation unit 106 switches the transport direction of the used paper 103 with one switching plate 112. However, the configuration of the separation unit 106 is not limited to the above configuration. Two switching plates that block the storage-side transport path 113 and the reversing-side transport path 114 may be used, or one switch plate that blocks only one of the transport paths may be used. The switching plate may not be provided, and only the transport roller may be provided. The point is that any function that can switch and transport the used paper 103 between the storage-side transport path 113 and the reverse-side transport path 114 based on the determination result of the detection unit 105 is sufficient.

Referring again to FIG. 1, the first storage unit 107
Denotes a storage tray for storing used paper 103 (not shown)
Used paper 10 that is provided to the storage-side transport path 113 by the separation unit 106.
When the transport rollers 3 are transported by the transport rollers 119, the transport rollers 3 are sequentially stacked in the storage tray from above, that is, from one direction, with the white surface facing upward. Therefore, the first storage unit 107 sequentially stores the used papers 103 in the storage tray with the white copy surface facing upward.

The first storage unit 107 includes a transport roller 118
Thus, the used papers 103 are sequentially sent out to the image forming unit 102 in order from the lowest used paper 103 in the storage tray, that is, in the order of being stacked on the storage tray.

The reversing unit 109 includes a plurality of transport rollers 120, 121, 122, 123, and 124 that form a reversing path.
When the used paper 103 switched to the reversing side conveyance path 114 side by the separation unit 106 is conveyed by the conveyance roller 125, the conveyance rollers 120, 121, and 12
The used paper 103 is sequentially conveyed and inverted at 2, 123, and 124 and sent out toward the second storage unit 108.

The second storage unit 108 stores the used paper 103
A storage tray (not shown) for storing
When the used paper 103 reversed by the reversing unit 109 is transported by the transport roller 128, the transport roller 126 moves the white surface (B surface) from above into the storage tray, that is, from one direction. Stack them up one by one. Therefore, the second storage unit 108 stores the used paper 1
03 are sequentially stacked and stored in the storage tray with the white copy side facing up.

The second storage unit 108 includes a transport roller 127
Thus, the used papers 103 are sequentially sent out to the image forming unit 102 in order from the lowest used paper 103 in the storage tray, that is, in the order of being stacked on the storage tray.

The used paper 103 sent out from the first storage unit 107 and the second storage unit 108 is conveyed by the conveying rollers 129 and 130 to the image forming unit 102.
Transported to

The image forming unit 102, as described above, uses the used paper 103 conveyed from the paper feeding system unit 101.
An image is recorded on the recording surface (copying surface) of the printer by an electrophotographic recording method, and the used paper 103 on which the image is recorded by the image forming unit 102 is discharged onto a discharge tray (not shown) by a discharge roller 131. Is done.

Next, the operation of the present embodiment will be described. It is determined whether or not the copy surface of the used paper 103 placed on the paper feed tray 104 is white, and is stored separately in the two storage units 107 and 108 according to whether or not the copy surface is white. The used paper 10 is sent from the storage units 107 and 108 to the image forming unit 102.
3 is supplied in the storage order to form an image.

That is, in the image forming apparatus 100, a plurality of used papers 103 used for image formation on only one side are placed on the paper feed tray 104, and the uppermost use paper in the paper feed tray 104 is transported by the transport roller 110. The used paper 103 is sequentially sent out to the conveyance roller 111 from the used paper 103, and the conveyance roller 111 conveys the used paper 103 to the detection unit 105.

The detecting unit 105 detects whether or not the copy surface (side A) of the used paper 103 is white, and outputs a detection result to the control unit. If it is (unrecorded), the separation unit 106 is controlled to
13 side, and the used paper 103 is stored in the first storage unit 1.
07, and are sequentially placed on the first storage unit 107 with the white copy side facing up. Further, when the copy surface of the used paper 103 is not white, the control unit
6 selects the reverse side conveyance path 114, and
Is transported to the reversing unit 109, and the used paper 103 is reversed by the reversing unit 109, and is sequentially placed on the second storage unit 108 with the white copy surface facing up.

In this way, the detection unit 105 detects whether or not the copy surface of the plurality of used papers 103 placed on the paper feed tray 104 is white. The used paper 103 having a white surface is stored in the first storage unit 107.
Then, after the used paper 103 whose copy surface is not white when passing through the detection unit 105 is reversed by the reversing unit 109, the second storage unit 108 sequentially stores the paper with the white surface facing up. By sequentially performing this operation, even when the used paper 103 placed on the paper feed tray 104 does not have a white surface and an already-formed image forming surface, the first storage unit 107 and the second storage unit A plurality of used papers 103 can be placed respectively with the white side (unused side) facing up appropriately.

In the state where the used paper 103 is placed on the first storage unit 107 and the second storage unit 108, an instruction for image formation is performed by the operation unit of the image forming apparatus 100. The control unit selectively uses the used paper 10 from one of the first storage unit 107 and the second storage unit 108.
3 is conveyed to the image forming unit 102 and the image forming unit 102 forms an image.

At this time, since the used paper 103 is stored in the first storage unit 107 and the second storage unit 108 with the white copy surface being aligned upward, the first storage unit The used paper 103 transported from the storage 107 or the second storage unit 108 to the image forming unit 102 is
The white surface faces the photosensitive drum No. 02, and the image is not formed again on the surface of the used paper 103 on which the image is already formed.

Note that the used paper 103 is simultaneously transferred from the first storage unit 107 and the second storage unit 108 to the image forming unit 102.
When the paper is sent to the transport route, a sensor for detecting the presence or absence of the paper is provided on the transport route so that the used paper 103 does not overlap in the transport route.

Also, the used paper 103 is preferentially supplied from one of the storage units 107 and 108 to the image forming unit 102.
The used paper 103 may be supplied to the image forming unit 102 from the other storage units 107 and 108 after the used paper 103 is exhausted in one of the storage units 107 and 108.

The image forming apparatus 100 includes an image forming unit 102
The used paper 103 on which the image is formed by the
To discharge onto a discharge tray (not shown).

As described above, in the image forming apparatus 100 of the present embodiment, the upper surface (Side A) of the used paper 103 sent out from the paper feed tray 104 on which the plurality of used paper The detection unit 105 detects whether the image forming surface is the image forming surface or the already-formed image forming surface, and based on the detection result, conveys the used paper 103 sent out from the paper feeding tray 104 directly to the first storage unit 107. Or reversing unit 1
09 and then transported to the second storage unit 108,
The used paper 103 is placed on the first storage unit 107 and the second storage unit 108 with the non-image forming surface (white surface) of the used paper 103 aligned on the upper side, and is placed on the first storage unit 107 and the second storage unit 108. The used paper 103 is selectively conveyed to the image forming unit 102 in the order in which the used paper 103 is placed first, and the image forming unit 102 forms an image on the non-image forming surface of the used paper 103.

Therefore, even when the used paper 103 is placed on the paper feed tray 104 in a state where the non-image-formed surface and the already-image-formed surface are not aligned, the image forming unit 102
It is possible to appropriately determine whether the surface on which an image is to be formed is an unimaged surface or an already-imaged surface, and automatically align the unimaged surfaces and store them in the first and second storage units 107 and 108. The used paper is conveyed from these storage units 107 and 108 to the image forming unit 102 in the order in which they are placed, and the user
It is possible to improve the usability of the image forming apparatus 100 by omitting the confirmation of the front and back sides and the necessity of performing re-copying / printing, etc., as well as the first storage unit 107 and the second storage unit 10.
8 can be carried out independently of the image formation by the image forming unit 102.
The image can be continuously formed on the used paper from the time when the used paper 103 is placed for the first time in 04, and the invention can be applied to the high-speed image forming apparatus 100.

Further, since the detection time in the detection unit 105 is not affected by the image forming speed in the image forming unit 102, the detection time in the detection unit 105 can be sufficiently secured, and the detection time can be used in a high-speed image forming apparatus. The used paper 103 can be reused without complicating the user.

Further, the used papers 103 are conveyed to the image forming unit 102 in the order in which they are stacked in the first storage unit 107 and the second storage unit 108, that is, the used papers 103 are stacked from the top and the bottom. Of the used paper 103 and the image forming unit 10
2 can be performed at the same time, and even if the used paper 103 is exhausted in the first storage unit 107 and the second storage unit 108 while image formation is performed continuously, As long as there is used paper 103 in the tray 104, the image forming speed is reduced, but continuous image formation is possible, and there is no time when a user cannot form an image.

In the present embodiment, the first storage unit 1
07, the used paper 103 is sequentially stacked in the second storage unit 108 from the upper side, and the used paper 10
3 are sequentially conveyed to the image forming unit 102, but in the first storage unit 107 and the second storage unit 108, the used paper 103 is sequentially stacked from the bottom, and the image forming unit 102 is sequentially stacked from the top. May be transported. Also, the first
The stacking directions of the storage unit 107 and the second storage unit 108 may be different. That is, the first storage unit 107
There is no limitation on the direction in which the used papers 103 are stacked in the second storage unit 108, and it is sufficient if the used papers 103 are stacked in one direction.

FIG. 3 is a diagram showing a second embodiment of the paper feeding system of the image forming apparatus according to the present invention. In this embodiment, the used paper whose front and back sides have been determined is stored in one storage unit as it is. Alternatively, it is reversed and placed with the white surfaces aligned, which corresponds to claim 2.

In the description of the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 3 shows an image forming apparatus 200 to which the second embodiment of the sheet feeding system of the image forming apparatus according to the present invention is applied.
FIG.

The image forming apparatus 200 includes the sheet feeding system 20
1 and an image forming unit 102 similar to the image forming apparatus 100 of the above-described embodiment.
The paper feed system includes a paper feed tray 104, a detection unit 105, a separation unit 106, a reversing unit 109, a conveyance roller 125, and the like, which are the same as those of the paper supply system 101 according to the embodiment. Have.

The transport rollers 202 and 203 are
5, the used paper 103 that has been determined to be white on the detection surface (A surface) and switched to the storage-side conveyance path 113 by the separation unit 106.
Is transported to the storage unit 206, and the transport roller 204 is switched to the reverse transport path 114 by the separation unit 106 when the detection surface (A surface) is determined to be the image-formed surface by the detection unit 105, Is conveyed to the storage unit 206.

That is, the image forming apparatus 2 of the present embodiment
In the sheet feeding system 201 of 00, only one storage unit 206 is provided, and the used paper 103 whose detection surface is white is transported to the storage unit 206 as it is, and the detection surface is determined to be the already-formed image forming surface. The used paper 103 is turned over and transported to the storage unit 206.

The storage unit 206 includes a storage tray (not shown) for storing the used paper 103 and transport rollers 207 and 208.
The used paper 103 switched to the storage-side transport path 113 by the separation unit 106 is
03, and is transported by the transport rollers 207.
The sheets are stacked in the storage tray from above, that is, from one direction, with the white surface facing upward. Therefore, the storage unit 206
Stores the used papers 103 sequentially in the storage tray with the white copy side facing up.

The storage unit 206 sequentially sends out the used papers 103 to the image forming unit 102 by the transport rollers 208 in order from the lowest used paper 103 in the storage tray, that is, in the order in which the used papers 103 are stacked on the storage tray. Used paper 103 sent out of the storage tray by rollers 208
Is transported to the image forming apparatus 102 by the transport roller 205.

The reversing unit 109 has the same configuration as the reversing unit 109 of the first embodiment, and the used paper 103 switched to the reversing-side transport path 114 by the separating unit 106 is used.
Is transported by the transport rollers 125, the transport rollers 120, 121, 122, 123, and 124 reverse the used paper 103 and send it out toward the storage unit 206.

The transport roller 204 transports the used paper 103 inverted by the reversing unit 109 to the storage unit 206, and the storage unit 206 transports the used paper 103 inverted by the reversing unit 109 by the transport roller 204. When they come, they are sequentially stacked in the storage tray from above, that is, from one direction with the white surface facing up. Therefore, the storage unit 206 places the used paper 103 directly conveyed from the separation unit 106 and the used paper 103 conveyed after being reversed by the reversing unit 109 in the storage tray with the white surface as a copy surface. Store in a stacked state.

Next, the operation of the present embodiment will be described. It is determined whether the detection surface of the used paper 103 placed on the paper feed tray 104 is white or not, and the used paper 103 is directly or inverted in one storage unit 206 depending on whether the detection surface is white or not. After storing, the image forming unit 1
The second embodiment is characterized in that the used paper 103 is supplied in the storage order to form an image.

That is, in the image forming apparatus 200, a plurality of used papers 103 used for image formation on only one side are placed on the paper feed tray 104, and the uppermost used paper in the paper feed tray 104 is conveyed by the transport roller 110. The used paper 103 is sequentially sent out to the conveyance roller 111 from the used paper 103, and the conveyance roller 111 conveys the used paper 103 to the detection unit 105.

The detection unit 105 detects whether the detection surface (Side A) of the used paper 103 is white and outputs the detection result to the control unit. The control unit determines that the detection surface of the used paper 103 is white. If it is (unrecorded), the separation unit 106 is controlled to
13 is selected, the used paper 103 is transported to the storage unit 206, and the used paper 103 is sequentially placed on the storage unit 206 with a white surface facing up as a copy surface. When the detection surface of the used paper 103 is not white, the control unit causes the separation unit 106 to select the reversing-side conveyance path 114, conveys the used paper 103 to the reversing unit 109, and Paper 10
After the front and back of No. 3 are reversed, they are sequentially placed on the storage unit 206 with the white side facing up as a copy side.

As described above, the detection unit 105 detects whether or not the detection surfaces of the plurality of used papers 103 placed on the paper feed tray 104 are white, and detects when the detection paper 105 passes through the detection unit 105. The storage unit 206 stores the used paper 103 having a white surface as it is.
Next, after the used paper 103 whose detection surface when passing through the detection unit 105 is not white is inverted by the inversion unit 109, the storage unit 2
At 06, the images are sequentially stored with their white surfaces facing up. By sequentially performing this operation, the paper feed tray 104
Even when the used paper 103 placed on the white paper and the image-formed surface are not aligned, the storage unit 206 stores a plurality of the used papers 10 with the white surface (unused surface) facing up properly.
3 can be placed.

At this time, the transport timing of the used paper 103 transported directly from the separation unit and 106 to the storage unit 206 and the used paper 103 transported to the storage unit 206 after being reversed by the reversing unit 109 to the storage unit 206. Is detected and controlled by a sensor or the like (not shown) that detects the presence or absence of the used paper 103 conveyed to the storage unit 206, so that the conveyance of the used paper 103 can be properly stored without causing a jam. The sheet can be conveyed and placed on the section 206.

As described above, the used paper 10 is stored in the storage unit 206.
When an image forming instruction operation is performed on the operation unit of the image forming apparatus 100 in a state where the storage unit 2 is placed, the control unit
From 06, the used paper 103 is conveyed to the image forming unit 102, and the image forming unit 102 forms an image.

At this time, since the used paper 103 is stored in the storage unit 206 with the white copy surface aligned upward, the used paper 103 transported from the storage unit 206 to the image forming unit 102 is stored. Are all white-faced with respect to the photosensitive drum of the image forming unit 102, and the image is not formed again on the surface of the used paper 103 on which the image is already formed.

The image forming apparatus 200 includes an image forming unit 102
The used paper 103 on which the image is formed by the
To discharge onto a discharge tray (not shown).

As described above, according to the image forming apparatus 200 of the present embodiment, the image forming surface of the used paper 103 sent out from the paper feed tray 104 on which the plurality of used paper The detection unit 105 detects whether the surface is the image forming surface or the image forming surface, and based on the detection result, the used paper 103 sent from the paper feed tray 104 is directly conveyed to the storage unit 206, or After being reversed by the reversing unit 109, the sheet is conveyed to the storage unit 206 and the used paper 10
3 are placed on the storage unit 206 sequentially with the non-image forming surfaces thereof aligned, and the used paper 103 is sequentially conveyed from the storage unit 206 to the image forming unit 102 in the order in which they were placed first.
At 02, an image is formed on the non-image forming surface of the used paper 103.

Therefore, even when the used paper 103 is placed on the paper feed tray 104 in a state where the unimaged surface and the already-imaged surface are not aligned, the image forming unit 102
It is properly determined whether the surface on which an image is to be formed is an unimaged surface or an already-imaged surface, and the unimaged surfaces are aligned to form one storage unit 20.
6 and a small and inexpensive configuration.
02 to improve the operability of the image forming apparatus 200 by transporting the used paper 103 in the order of placement and eliminating the need for the user to check the front and back of the used paper 103 and to perform copying / printing again. Further, an image can be continuously formed on the used paper from the time when the used paper 103 is first placed on the paper feed tray 104, and the high-speed image forming apparatus 200
Can also be applied.

FIG. 4 is a diagram showing a third embodiment of the paper feeding system of the image forming apparatus according to the present invention. In this embodiment, it is detected whether images have been formed on both sides of used paper. If the image has been formed on both sides, the image data is stored in the paper discharge storage unit.

Note that the present embodiment is applied to an image forming apparatus similar to the image forming apparatus of the first embodiment, and in the description of the present embodiment, the first embodiment will be described. The same components as those in the embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 4 shows an image forming apparatus 300 to which the third embodiment of the sheet feeding system of the image forming apparatus according to the present invention is applied.
FIG.

The image forming apparatus 300 includes the sheet feeding system 30
1 and an image forming unit 102 similar to the image forming apparatus 100 of the above-described embodiment.
The paper feed tray 104, the detection unit 105, the first storage unit 107, the second storage unit 108, the reversing unit 109, and the transport rollers 119 and 12 are the same as those of the paper feed system 101 according to the embodiment.
5, 128, etc., as well as a detection unit 302, a separation unit 303, transport rollers 304, 305, a paper discharge storage unit 306, and the like.

The detection section 302 is disposed so as to face the detection section 105, and uses, for example, a reflection type photo sensor or a reflection type line sensor. The detection unit 302 detects whether the B side of the used paper 103 on which an image is formed by the image forming unit 102 is white, and outputs a detection result to a control unit (not shown).

The separation unit 303 includes a storage-side conveyance path 113 on the first storage unit 107 side and a reversal-side conveyance path 1 on the reversing unit 109 side, similar to the separation unit 106 of the first embodiment.
14 and a paper discharge side conveyance path 307 on the paper discharge storage unit 306 side.
And transport rollers 115 and 116 and a transport roller 308 similar to the separation unit 106 of the first embodiment, and further, the transport direction of the used paper 103 is changed by the storage-side transport path 113, A switching plate (not shown) for switching to the side conveyance path 114 and the sheet discharge side conveyance path 307 is provided.

The separation unit 303 operates under the control of a control unit (not shown), and based on the detection results of the detection unit 105 and the detection unit 302, separates the used paper 103 transported from the paper feed tray 104 into the storage side. Conveyance path 113, reverse side conveyance path 1
14 and one of the paper discharge side transport paths 307 for transport. That is, the separation unit 303
If the surface A of the used paper 103 is white and the surface B is the image-formed surface, the used paper 103 is transported to the storage-side transport path 113, and the surface A of the used paper 103 is the image-formed surface. ,
If the side B is a white side (non-image forming side), the used paper 10
3 is conveyed to the reversing-side conveyance path 114, and if both the A-side and the B-side of the used paper 103 are image-formed surfaces, the used paper 103 is conveyed to the discharge-side conveyance path 307.

The transport rollers 308, 304, and 305 transport the used paper 103 switched to the discharge side transport path 307 by the separation unit 302 to the paper output storage unit 306.

The paper discharge storage unit 306 includes a transport roller 309 and a storage tray (not shown). The transport roller 309 sequentially stacks the transported used paper 103 on both sides recorded in the storage tray from above. I do.

Next, the operation of the present embodiment will be described. The image forming apparatus 300 determines whether the surface A of the used paper 103 placed on the paper feed tray 104 is white, and outputs the used paper 103 to the first paper based on whether the surface A is white. Storage unit 107
And stored in the second storage unit 108 via the reversing unit 109 and the used paper 10 having both sides recorded.
3 is stored in the paper discharge storage unit 306, the used paper 103 is supplied from the first storage unit 107 and the second storage unit 108 to the image forming unit 102, and an image is formed.

That is, in the image forming apparatus 300, the plurality of used sheets 103 on which an image has been formed
And the paper feed tray 104
The conveying rollers 11 are sequentially arranged from the uppermost used paper 103 in the inside.
1, and the transport roller 111 transports the used paper 103 to the detection unit 105 and the detection unit 302.

The detection unit 105 and the detection unit 302 detect whether the A side and the B side of the used paper 103 are white, respectively.
The detection result is output to the control unit, and the control unit
If the A side of No. 3 is white (unrecorded) and the B side is recorded or white, the separation unit 303 is controlled to select the storage side conveyance path 113 side, and the used paper 103 is stored in the first storage unit. The document is conveyed to the first storage unit 107 and sequentially placed on the first storage unit 107 with the white surface facing upward as a copy surface. Further, when the side A of the used paper 103 is already recorded and the side B is white, the control unit causes the separation unit 303 to select the reversing side conveyance path 114 and conveys the used paper 103 to the reversing unit 109. And reversal unit 1
After turning over the used paper 103 in step 09, the used paper 103 is sequentially placed in the second storage unit 108 with the white surface facing up as a copy surface. Further, the control unit controls the A
When both sides B and B have been recorded, the separation unit 303
To select the discharge side transport path 307, and the transport rollers 308,
The sheet is conveyed to the paper discharge storage unit 306 by 304 and 305,
The discharged paper storage unit 306 sequentially stores the used paper 103 having both sides recorded.

In this manner, the detection unit 105 and the detection unit 302 detect whether the surfaces A and B of the plurality of used papers 103 placed on the paper feed tray 104 are white or not. 1
05 and the used paper 103 whose white side A, which is a copy side when passing through the detection unit 302, is used as the first storage unit 107.
Then, after the used paper 103 whose copy side is recorded and the non-copy side is white when passing through the detection unit 105 is reversed by the reversing unit 109, the white surface is placed in the second storage unit 108, respectively. In this state, the used paper 103 having both sides recorded is discharged and stored in the discharge storage unit 306 while being sequentially stored. By sequentially performing this operation, the first storage unit 107 and the second storage unit 10 can be used even when the used paper 103 placed on the paper feed tray 104 does not have the white surface and the image-formed surface.
8, a plurality of used papers 103 can be placed with the white surface (unused surface) facing up, and
The used paper 103 having both sides recorded is stored in the paper discharge storage unit 306, and the used paper 103 having both sides recorded is prevented from being stored in the first storage unit 107 or the second storage unit 108. be able to.

When the used paper 103 is placed on the first storage unit 107 and the second storage unit 108 in this manner, when an instruction for image formation is performed on the operation unit of the image forming apparatus 100, The control unit appropriately conveys the used paper 103 from the first storage unit 107 and the second storage unit 108 to the image forming unit 102 in the storage order, and causes the image forming unit 102 to form an image.

At this time, since the used paper 103 is stored in the first storage unit 107 and the second storage unit 108 with the white copy surface facing upward, the first storage unit 107
The used paper 103 conveyed from the second storage unit 108 to the image forming unit 102 has a white surface facing the photosensitive drum of the image forming unit 102, and an image of the used paper 103 has already been formed on the used paper 103. The image is not formed again on the surface where the light is present.

The image forming apparatus 200 includes the image forming section 102
The used paper 103 on which the image is formed by the
To discharge onto a discharge tray (not shown).

As described above, in the image forming apparatus 200 according to the present embodiment, the detection unit 105 and the detection unit 302 detect whether the both sides of the used paper 103 sent out from the paper supply tray 104 are the non-image forming surface or the already formed image. It is detected whether or not the used paper 103 is the formed surface, and if both surfaces of the used paper 103 are the already-formed image forming surfaces, the used paper 103 is conveyed and placed on the paper discharge storage unit 306.

Therefore, when the used paper 103 placed on the paper feed tray 104 has already been image-formed on both sides, it is possible to prevent the image from being erroneously formed on the already-formed image forming surface and to surely prevent the non-image formation. An image can be formed on the formation surface, and the usability of the image forming apparatus 300 can be further improved.

The paper discharge storage unit 306 is provided in the image forming unit 10.
2 is different from the paper discharge tray from which the paper on which the image is formed is discharged, the used paper 103 on which an image is already formed on both sides and the used paper 103 on which the image is formed by the image forming unit 102 are used. Image forming apparatus 3
00 can be improved.

In this embodiment, when the paper discharge storage unit 306 is not provided outside, the paper discharge storage unit 3
When 06 is full of used paper 103 on which both-sided images have been formed, it is necessary to temporarily stop the operation of image forming apparatus 300, open the housing, and take out used paper 103 from paper output storage unit 306. At least the used paper 103 on which images are already formed on both sides is erroneously
Is less likely to be mixed with the used paper 103 set in the printer, so that the usability is less likely to be impaired.

FIG. 5 is a view showing a fourth embodiment of the paper feeding system of the image forming apparatus according to the present invention. In this embodiment, a used storage sheet whose front and back sides have been determined is directly stored in one storage unit. Alternatively, a paper feed system for inverting and placing the paper with the white surfaces aligned is incorporated in the paper feed tray, and corresponds to claims 5 and 6.

In the description of the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 5 shows an image forming apparatus 400 to which the second embodiment of the sheet feeding system of the image forming apparatus according to the present invention is applied.
FIG.

The image forming apparatus 400 includes a paper feed tray 401
And an image forming unit 102 similar to the image forming apparatus 100 of the above-described embodiment, and a paper feeding system 402 is housed in a paper feeding tray 401.

The paper feeding system 402 includes a tray body (mounting section) 403, a detecting section 404, transport rollers 405 and 40.
6, a storage unit 407, a reversing unit 408, and the like, and a plurality of used papers 103 are placed in the tray main body 403.

As the detection unit 404, for example, a reflection type photo sensor or a reflection type line sensor is used, and the used paper 103 placed in the tray main body 403 is used.
Is detected whether or not the upper surface (A surface) is white, and is output to a control unit (not shown).

Under the control of the control unit, the transport rollers 405 and 406 rotate clockwise and counterclockwise in FIG. 5, and the direction indicated by the arrow in FIG. 5, ie, the direction of the storage unit 407, and the arrow in FIG. And the direction of the reversing unit 408 shown in FIG. The reversing unit 408 includes a transport roller 409,
410, 411, 412, 413, etc., the used paper 103 sent out in the direction of the arrow by the conveyance rollers 405, 406 is sequentially conveyed, and the used paper 103 is turned upside down. 407.

The storage unit 407 includes a storage tray (not shown) for storing the used paper 103 and transport rollers 414 and 415.
And the like.
The conveyed used paper 103 is conveyed, and is sequentially stacked in one direction from the lower side of the storage tray by the conveyance roller 414. Therefore, the storage unit 407 stores the used paper 10
3 are sequentially stacked and stored from below in the storage tray with the white side facing up as the copy side.

The storage unit 407 sequentially sends out the used papers 103 to the image forming unit 102 by the transport rollers 415 in order from the topmost used papers 103 in the storage tray, that is, in the order in which the used papers 103 are stacked on the storage tray. The used paper 103 sent out from the roller 415 is conveyed by the conveying roller 416 to the image forming unit 102.

Next, the operation of the present embodiment will be described. Paper feed system 402 incorporated in paper feed tray 401
Detects whether the A side of the used paper 103 placed on the tray main body 403 is white and stores the used paper 103 as it is in one storage unit 407 according to whether the A side is white or not. The feature is that the paper is stored after being inverted, and the used paper 103 is supplied from the storage unit 407 in the paper feed tray 401 to the image forming unit 102 to form an image.

That is, the image forming apparatus 400 includes the upper surface of the uppermost used sheet 103 of the plurality of used sheets 103 used for image formation on only one side placed on the tray main body 403 in the sheet feeding tray 401. The detection unit 404 detects whether the (A side) is white or not and outputs it to the control unit. If the A side of the used paper 103 is white (unrecorded), the control unit determines that the conveyance rollers 405 and 406 Is rotated counterclockwise, and is directly conveyed from the tray body 403 to the storage unit 407. Storage unit 40
7 places the conveyed used paper 103 in the storage tray sequentially from the bottom.

If the A-side of the topmost used paper 103 in the tray main body 403 is not white but has been recorded, the control unit rotates the transport rollers 405 and 406 clockwise to send the paper to the reversing unit 408. , The reversing unit 408 is provided in the tray body 40.
The used paper 103 sent out from the printer 3 is turned upside down and conveyed to the storage unit 407 with its white side (non-recorded side) facing up. The storage unit 407 places the transported used paper 103 in the storage tray sequentially from the bottom.

In this way, the detection unit 404 detects whether the upper surface (Surface A) of the plurality of used papers 103 placed on the tray main body 403 is white, and If the side A of the used paper 103 is white, the used paper 103 is sent directly to the storage unit 407 and the tray body 4
When the A side of the topmost used paper 103 of 03 is not white, the used paper 103 is sent out to the reversing unit 408, and
After reversing by the reversing unit 408, the storage unit 407 sequentially stores the images with the white surface facing up as a copy surface. By sequentially performing this operation, the tray body 403
When the used paper 103 placed in the storage unit 407 is not aligned with the white surface and the image-formed surface, the storage unit 407 appropriately stores a plurality of sheets with the white surface (unused surface) facing up as a copy surface. The used paper 103 can be placed.

At this time, the used paper 103 transported directly from the tray body 403 to the storage unit 407 and the used paper 103 transported to the storage unit 407 after being inverted by the reversing unit 408.
The transfer timing to the storage unit 407 for the
By adjusting the detection timing, the used paper 103 can be properly transported to the storage unit 407 and placed thereon without causing a jam in the transport of the used paper 103.

As described above, the used paper 10 is stored in the storage unit 407.
When an image forming instruction operation is performed on the operation unit of the image forming apparatus 400 in a state where the sheet 3 is placed, the control unit drives the transport roller 415 to send the uppermost used sheet 103 from the storage unit 407 to the storage unit 407. Are sequentially transported to the image forming unit 102 in the storage order, and the image forming unit 102 forms an image.

At this time, since the used paper 103 is stored in the storage unit 407 with the white copy surface aligned upward, the used paper 103 transported from the storage unit 407 to the image forming unit 102 is used. Are all white-faced with respect to the photosensitive drum of the image forming unit 102, and the image is not formed again on the surface of the used paper 103 on which the image is already formed.

The image forming apparatus 400 includes the image forming section 102
The used paper 103 on which the image is formed by the
To discharge onto a discharge tray (not shown).

As described above, the image forming apparatus 400 according to the present embodiment merely replaces the paper feed tray of the existing image forming apparatus with the paper feed tray 401 according to the present embodiment. The image forming apparatus 4 can appropriately perform image formation using the used paper 103 without adding complexity such as checking the front and back of the image 103 and forming an image again.
00 can be made inexpensive and have good usability.

In the present embodiment, a sheet feeding system 402 similar to that of the second embodiment is used.
However, the paper supply system 101 similar to that of the first embodiment may be incorporated in the paper supply tray 401.

FIG. 6 is a view showing a fifth embodiment of the paper feeding system of the image forming apparatus according to the present invention. Or put it upside down and put it on the white side,
A paper feeding system for discharging used paper on which double-side recording has been performed to a paper output storage unit is incorporated in a paper feeding tray, and corresponds to claims 5 and 6.

In the description of the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 6 shows an image forming apparatus 500 to which the fifth embodiment of the sheet feeding system for an image forming apparatus according to the present invention is applied.
FIG.

The image forming apparatus 500 includes a paper feed tray 501.
And an image forming unit 102 similar to the image forming apparatus 100 of the above-described embodiment, and a paper feed system 502 is housed in a paper feed tray 501.

The paper feeding system 502 includes a tray main body (mounting section) 503, detecting sections 504 and 505,
6, 507, 508, 509, 510, storage unit 511,
The tray unit 503 includes a separation unit 512, a reversing unit 513, a paper discharge storage unit 514, and the like.
Are placed.

As the detection unit 504, for example, a reflection type photo sensor or a reflection type line sensor is used, and the used paper 103 placed in the tray main body 503 is used.
Is detected whether or not the upper surface (A surface) is white, and the detection result is output to a control unit (not shown).

As the detection unit 505, for example, a reflection type photo sensor or a reflection type line sensor is used, and the B side of the used paper 103 conveyed from the tray body 503 to the separation unit 512, that is, the tray Detects whether the surface that was the lower surface when placed on the main body 503 is white,
The detection result is output to a control unit (not shown).

The transport rollers 506 and 507 rotate clockwise and counterclockwise in FIG. 6 under the control of the control unit, and rotate in the directions indicated by the arrows in FIG. 6, ie, the direction of the storage unit 511 and the arrows in FIG. And the direction of the separation unit 512 shown in FIG.

The transport rollers 508 and 509 transport the used paper 103 sent from the tray body 503 in the direction of the separation unit 512 to the separation unit 512, and the detection unit 505
It is detected whether or not the B side of the used paper 103 conveyed in the direction of the separation unit 512 indicated by the arrow is white.

The separation unit 505 is provided with conveying rollers 515 and 51
6, a switching plate (not shown), and the like. Under the control of the control unit, based on the detection result of the detection unit 505, the conveyed used paper 103 is turned over by the reversing unit 51 indicated by an arrow in FIG.
The sheet is switched by the switching plate to the side 3 and the paper discharge storage section 514 indicated by the arrow, and is sent out by the transport rollers 515 and 516, respectively.

The reversing unit 513 includes transport rollers 517 and 51
8 and the like, and the separation unit 515 switches to the reversing unit 513 side and sequentially conveys the used paper 103 sent out,
After the used paper 103 is turned upside down, the transport rollers 50
The sheet is conveyed to the storage unit 511 according to steps 9 and 510.

The storage unit 511 includes a storage tray (not shown) for storing the used paper 103 and transport rollers 519 and 520.
And the like, and directly from the tray body 503 and the reversing unit 513.
The conveyed used paper 103 is conveyed, and the conveyance paper 519 sequentially stacks the used paper 103 in one direction from below the storage tray. Therefore, the storage unit 511 stores the used paper 10
3 are sequentially stacked and stored from below in the storage tray with the white side facing up as the copy side.

The storage section 511 sequentially sends out the used papers 103 to the image forming section 102 by the transport rollers 520 in order from the topmost used papers 103 in the storage tray, that is, in the order in which the used papers 103 are stacked on the storage tray. The used paper 103 sent out from the roller 520 is conveyed by the conveying roller 521 to the image forming unit 102.

The paper discharge storage unit 514 includes a transport roller 522 and a storage tray (not shown). The transport roller 522 sequentially transfers the double-sided recorded used paper 103 transported from the separation unit 512 into the storage tray from above. Stack and store. An opening 501a is formed in the discharge tray 501 above the discharge storage unit 514, and the opening 501a is formed.
From the used paper 10 in the storage tray of the paper output tray 501
3 can be appropriately taken out.

Next, the operation of the present embodiment will be described. The image forming apparatus 500 according to the present embodiment
The paper feed system 502 incorporated in the tray main body 5
It is determined whether or not the A side of the used paper 103 placed on the sheet 03 is white, and the storage unit 511 stores the used paper 103 as it is or after inverting it according to whether or not the A side is white. At the same time, it is detected whether or not both sides have been recorded, and the used paper that has been recorded on both sides is discharged to the paper output storage unit 514, and the used paper 103 from the storage unit 511 in the paper feed tray 501 to the image forming unit 102. The characteristic is that the image formation is performed by supplying the image data.

That is, in the image forming apparatus 500, the upper surface (A side) of the uppermost used sheet 103 of the plurality of used sheets 103 placed on the tray main body 503 in the sheet feeding tray 501 is white. The detection unit 504 detects whether or not the used paper 103 is white (unrecorded) and outputs the same to the control unit. When the A side of the used paper 103 is white (unrecorded), the control unit rotates the conveyance rollers 506 and 507 counterclockwise. , The storage unit 51 directly from the tray body 503
Convey to 1. The storage unit 511 sequentially places the conveyed used papers 103 in the storage tray with the white side, which is the A side, facing upward from the bottom.

When the surface A of the topmost used sheet 103 in the tray main body 503 is not white and has been recorded, the control unit rotates the conveying rollers 506 and 507 clockwise to send the sheet to the separation unit 512. Then, the sheet is conveyed to the separation unit 512 by the conveyance rollers 508 and 509, and the detection unit 505 determines whether or not the B side of the used paper 103 conveyed to the separation unit 512 is white.
To detect.

When the side B of the used paper 103 conveyed to the separation unit 512 is white, the separation unit 512 switches the used paper 103 to the reversing unit 513 and sends it out. Turn the paper 103 upside down,
The paper is conveyed to the storage unit 511 with the white surface facing up by the conveyance rollers 509 and 510. The storage unit 511 places the conveyed used paper 103 in the storage tray with the white surface facing upward from the bottom.

When the B side of the used paper 103 conveyed to the separation unit 512 has been recorded, the separation unit 512 switches the used paper 103 to the discharge storage unit 514 and sends it out. Is used paper 10
3 are sequentially stacked in the storage tray from above by the transport rollers 522 and stored.

As described above, the sheet feeding system 502 of the image forming apparatus 500 determines whether the A side of the plurality of used sheets 103 placed on the tray main body 503 is white or not.
4, if the A side of the uppermost used paper 103 of the tray main body 503 is white, the used paper 103 is sent directly to the storage unit 511, and the uppermost used paper 103 of the tray main body 503 is When the side A is not white, the used paper 103 is sent out to the separation unit 512 and the used paper 103 is sent out.
The detection unit 505 detects whether the side B is white. The paper feeding system 502 determines that the side B of the used paper 103 is white.
The used paper 103 is sent to the reversing unit 513 by the separating unit 512, and is reversed by the reversing unit 513, and then is stored in the storage unit 511.
Then, the sheets are sequentially stored with their white sides facing up, and if the B side of the used paper 103 has been recorded, the separation unit 512
Then, the sheet is sent to the paper discharge storage unit 514,
In the storage tray. By sequentially performing this operation, even when the used paper 103 placed on the tray main body 503 does not have the white surface and the already-formed image forming surface aligned,
A plurality of used papers 103 can be placed in the storage unit 511 with the white side (unused side) facing up appropriately, and the used papers 103 having both sides recorded are stored in the discharge storage unit 514. And the used paper 103 that has been double-sided recorded can be prevented from being stored in the storage unit 511.

At this time, the used paper 103 transported directly from the tray body 503 to the storage unit 511 and the used paper 103 transported to the storage unit 511 after being inverted by the reversing unit 513.
The transfer timing to the storage unit 511 is determined by the detection unit 504.
By adjusting the detection timing, the used paper 103 can be properly transported to the storage unit 511 and loaded without causing a jam in the transport of the used paper 103.

As described above, the used paper 10 is stored in the storage unit 511.
When an image forming instruction operation is performed on the operation unit of the image forming apparatus 500 in a state in which the sheet 3 is placed, the control unit drives the transport roller 415 to cause the storage unit 511 to output the topmost used paper 103 from the storage unit 511. Are sequentially conveyed to the image forming unit 102 and the image forming unit 102 forms an image.

At this time, since the used paper 103 is stored in the storage unit 511 in a state where the white side is aligned as a copy surface, the used paper 103 conveyed from the storage unit 511 to the image forming unit 102 is used. Are all white-faced with respect to the photosensitive drum of the image forming unit 102, and the used paper 10
No image is formed again on the surface of No. 3 on which an image is already formed.

Image forming apparatus 500 includes image forming section 102
The used paper 103 on which the image is formed by the
To discharge onto a discharge tray (not shown).

As described above, in the image forming apparatus 500 according to the present embodiment, an image is already formed on both sides only by replacing the sheet feeding tray of the existing image forming apparatus with the sheet feeding tray 501 of the present embodiment. Even if the used paper 103 is mistakenly mixed in the tray main body 503, it is possible to prevent an image formation error such that an image is formed again on the surface of the used paper 103 on which an image is already formed, The image forming apparatus 500 can be inexpensive and have good usability.

Further, the paper discharge storage unit 51 of the paper feed tray 501
4, the opening 501a is formed in the upper part, so that the image forming apparatus 500 does not need to be stopped, and
4, the used paper 103 on which images are already formed on both sides can be taken out, and the usability of the image forming apparatus 500 can be further improved.

FIG. 7 is a view showing a sixth embodiment of the paper feeding system of the image forming apparatus according to the present invention. 4. A paper feeding system in which a white paper is determined from the back side and a paper feeding system for placing used paper as it is or inverting in one storage unit and placing the white paper with the white paper aligned is incorporated in the paper feeding tray. 5 and claim 6.

This embodiment is applied to an image forming apparatus similar to the image forming apparatus of the fourth embodiment, and in the description of the present embodiment, the fourth embodiment will be described. The same components as those in the embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 7 shows an image forming apparatus 600 to which a sixth embodiment of the sheet feeding system of the image forming apparatus according to the present invention is applied.
FIG.

The image forming apparatus 600 includes a paper feed tray 601
And an image forming unit 102 similar to that of the image forming apparatus 100 of the above-described embodiment, and a sheet feeding system 602 is housed in a sheet feeding tray 601.

The paper feeding system 602 includes a storage section 407 and a reversing section 408 similar to those in the fourth embodiment, and further includes a tray body 603, a detection section 604, transport rollers 605 and 606, and the like. A plurality of used paper sheets 103 are placed in the 603.

A plurality of used papers 103 are placed on the tray main body 603 with the image-formed surface facing up, that is, in a state where the recorded surface can be confirmed. B, which is the lower surface of the lowermost used sheet 103 conveyed next in the tray main body 603 by the detection unit 604
An opening (not shown) capable of detecting whether the surface is recorded or white is formed.

The detection unit 604 uses, for example, a reflection type photo sensor or a reflection type line sensor, and detects the lowermost used sheet 103 to be conveyed next after being placed in the tray main body 603. It detects whether the lower surface (B surface) is white or not and outputs the detection result to a control unit (not shown).

The transport rollers 605 and 606 rotate clockwise and counterclockwise in FIG. 7 under the control of the control unit, and rotate in the directions indicated by the arrows in FIG. 7, that is, the direction of the reversing unit 408 and the arrows in FIG. And the direction of the storage unit 407 shown in FIG.

The reversing unit 408 has the same configuration as that of the fourth embodiment, and includes transport rollers 409, 410, and 41.
1, 412, 413, etc., and transport rollers 605, 60
6, the used paper 103 sent out in the direction of the arrow is sequentially conveyed, and the used paper 103 is turned upside down.
The sheet is transported to the storage unit 407 by the transport roller 413.

The storage section 407 has the same configuration as that of the fourth embodiment, and includes a storage tray (not shown) for storing the used paper 103 and transport rollers 414 and 415. The used paper 103 turned upside down by the reversing unit 408 is conveyed, and is sequentially stacked in one direction from below the storage tray by the conveyance rollers 414. Therefore, the storage unit 407 sequentially stores the used papers 103 from the bottom in the storage tray with the white surface facing upward as a copy surface.

The storage unit 407 sends out the used papers 103 to the image forming unit 102 in order from the topmost used papers 103 in the storage tray by the transport rollers 415, that is, in the order in which the used papers 103 are stacked on the storage tray. The used paper 103 sent out from the roller 415 is conveyed by the conveying roller 416 to the image forming unit 102.

Next, the operation of the present embodiment will be described. The image forming apparatus 600 according to the present embodiment includes a paper feed tray 601.
The paper feeding system 602 incorporated in the tray main body 6
03, the used paper 10 placed with the image forming side up
It is determined whether the lower surface (B side) of the sheet 3 is white or not, and the used paper 103 is inverted or stored in one storage unit 407 according to whether the side B is white or not. 60
1 is that the used paper 103 is supplied from the storage unit 407 in the storage unit 1 to the image forming unit 102 to form an image.

That is, the image forming apparatus 600 is placed on the tray main body 603 in the paper feed tray 601 with the image recording surface facing up, and only one side placed on the tray main body 603 is used for image formation. Multiple used paper 10
The detection unit 604 detects whether or not the lower surface, which is the B surface of the used paper 103 at the lowermost stage of the third paper, is white, and outputs it to the control unit. In the case of (recording), the conveying rollers 605 and 606 are rotated counterclockwise to be sent out from the tray main body 603 to the reversing unit 408, and the reversing unit 408 turns the front and back of the used paper 103 sent out from the tray main body 603. The sheet is inverted and conveyed to the storage unit 407 with the white side (non-recorded side) facing up. Storage unit 407
Puts the conveyed used paper 103 in the storage tray sequentially from the bottom.

If the B side of the lowermost used paper 103 in the tray main body 603 is not white and has been recorded, the control unit rotates the transport rollers 605 and 606 clockwise to directly store the paper in the storage unit. 407. The storage unit 407 places the transported used paper 103 in the storage tray sequentially from the bottom.

As described above, the detection unit 604 detects whether the lower surface (Side B) of the lowermost used paper 103 of the plurality of used papers 103 placed on the tray main body 603 is white. If the B-side of the lowermost used paper 103 of the tray main body 603 is white, the lowermost used paper 103 is sent out to the reversing unit 408, reversed by the reversing unit 408, and then stored in the storage unit 407. When the B side of the lowermost used paper 103 of the tray main body 603 is not white, the lowermost used paper 103 is directly sent to the storage unit 407, and the white surface is set as a copy surface. The data is sequentially stored in the storage unit 407. By sequentially performing this operation, even when the used paper 103 placed on the tray main body 603 with the image forming surface facing up is not aligned with the white surface and the image forming surface, the storage unit 407 can appropriately store the used paper 103. A plurality of used papers 103 can be placed with the white surface (unused surface) facing upward.

At this time, the used paper 103 transported directly from the tray body 603 to the storage unit 407 and the used paper 103 transported to the storage unit 407 after being inverted by the reversing unit 408
The transfer timing to the storage unit 407 for the
By adjusting the detection timing, the used paper 103 can be properly transported to the storage unit 407 and placed thereon without causing a jam in the transport of the used paper 103.

As described above, the used paper 10 is stored in the storage unit 407.
When an image forming instruction operation is performed on the operation unit of the image forming apparatus 600 in a state in which the sheet 3 is placed, the control unit drives the transport roller 415 to send the uppermost used sheet 103 from the storage unit 407 to the storage unit 407. Are sequentially conveyed to the image forming unit 102 and the image forming unit 102 forms an image.

At this time, since the used paper 103 is stored in the storage unit 407 with the white copy surface aligned upward, the used paper 103 transported from the storage unit 407 to the image forming unit 102 is used. Are all white-faced with respect to the photosensitive drum of the image forming unit 102, and the image is not formed again on the surface of the used paper 103 on which the image is already formed.

Image forming apparatus 600 includes image forming section 102
The used paper 103 on which the image is formed by the
To discharge onto a discharge tray (not shown).

As described above, in the image forming apparatus 600 according to the present embodiment, the used paper 103 is placed on the tray main body 603 with the image-formed surface up, and based on the detection result of the detection unit 604, The sheet is conveyed to the storage unit 407 in a state where the surface opposite to the already formed image surface is the image forming surface of the image forming unit 102.

Therefore, when the used paper 103 is set in the tray main body 603, the used paper 103 can be set while checking the image-formed surface of the used paper 103, and when a plurality of paper cassettes are provided. Thus, the paper feed cassette in which the used paper 103 is set and the paper feed cassette in which the unused paper is set can be easily recognized. As a result, it is possible to prevent the paper from being mistaken such that another paper is erroneously supplied in place of the used paper 103, and the user can feed the paper tray 601 on which the used paper 103 is placed into another paper supply tray. It is possible to prevent mistakes made for the paper tray and mistake the image forming apparatus 60.
0 can be further improved, the invention made by the inventor has been specifically described based on the preferred embodiments, but the present invention is not limited to the above, It goes without saying that various changes can be made without departing from the gist of the invention.

[0180]

According to the sheet feeding system of the image forming apparatus according to the first aspect of the present invention, one surface of the used paper sent out from the mounting portion on which the plurality of used papers are mounted is removed. The detection unit detects whether the detection surface is a non-image-formed surface or an already-image-formed surface as a detection surface. Based on the detection result, the used paper sent from the placement unit is directly sent to the first surface. After being conveyed to the storage unit or inverted by the reversing unit, it is conveyed to the second storage unit, and the unimaged surface or the already imaged surface of the used paper is aligned and sequentially with the first storage unit. Placed in the second storage unit, the used paper is selectively transported from the first storage unit and the second storage unit to the image forming unit sequentially in the order in which they are placed first, and the image forming unit Since the image is formed on the non-image forming surface of the used paper, the used paper is aligned with the non-image forming surface Even when the image forming unit is placed in a state where it is not set, it is appropriately determined whether the surface on which an image is formed by the image forming unit is a non-image forming surface or a previously formed image forming surface. The used paper can be stored in the second storage unit, and the used paper is transported from these storage units to the image forming unit in the order in which they are placed.
It is possible to improve the usability by omitting printing and the like, and it is possible to continuously form an image on the used paper from the time when the used paper is loaded on the loading section for the first time. It can also be applied to devices.

According to the paper feeding system of the image forming apparatus of the present invention, the image forming surface of the used paper sent out from the mounting portion on which a plurality of used papers are mounted is not image-formed. The detection unit detects whether the surface is a surface or an image-formed surface, and based on the detection result, the used paper sent from the placement unit is directly conveyed to the storage unit, or inverted by the reversing unit. After that, the paper is transported to the storage unit, and the unimaged surface or the already-imaged surface of the used paper is aligned and sequentially placed on the storage unit, and the used paper is sequentially placed from the storage unit in the order in which the paper is first placed. Since the sheet is conveyed to the image forming unit and the image forming unit forms an image on the non-image forming surface of the used sheet, the used sheet is not aligned with the image forming surface on the placing unit. If the surface on which the image is to be formed by the image forming unit is not Whether the image forming surface by appropriately determine,
The unimaged surfaces can be aligned and stored in one storage unit, so that a compact and inexpensive configuration can be achieved. In addition, used paper can be transported from the storage unit to the image forming unit in the order of placement and used. Confirmation of the front and back of used paper and copying /
It is possible to improve the usability by omitting printing and the like, and furthermore, it is possible to continuously form an image on the used paper from the time when the used paper is mounted on the mounting portion for the first time, and it is also possible to perform high-speed printing. The present invention can also be applied to an image forming apparatus.

According to the paper feeding system of the image forming apparatus according to the third aspect of the present invention, the surface opposite to the surface of the used paper sent from the placement unit which is detected by the detection unit is the non-image forming surface. The second detection unit detects whether the surface is an image-formed surface or not. If both the detection unit and the second detection unit detect that the image is the image-formed surface, both sides of the used paper are converted to the image-formed surface. The used paper is transported and placed on the paper output storage unit where the used paper is sequentially placed.If the used paper placed on the loading unit is already image-formed on both sides, the By preventing image formation on the formation surface, it is possible to reliably form the image on the non-image formation surface, and the usability of the paper feeding system of the image forming apparatus can be further improved.

According to the sheet feeding system of the image forming apparatus of the present invention, the used sheet is placed on the placing section with the image-formed surface up, and based on the detection result of the detecting section, It is transported to the first storage unit, the second storage unit, or the storage unit in a state where the surface opposite to the image-formed surface is the image forming surface in the image forming unit. When setting used paper, it is possible to set the used paper while checking the image-formed surface of the used paper. It is possible to easily recognize the setting section on which the unused sheets are set, and the usability of the sheet feeding system of the image forming apparatus can be further improved.

According to the sheet feeding system of the image forming apparatus of the present invention, the detecting unit is provided for detecting one side of the used sheet to be sent out next among the used sheets mounted on the mounting unit. Is used as a detection surface to detect whether the detection surface is a non-image-formed surface or an already-formed image-formed surface. It is possible to appropriately determine whether a surface on which an image is to be formed by the image forming unit is a non-image-formed surface or a previously-formed image-formed surface.

According to the paper feeding system of the image forming apparatus of the invention, the placing section, the detecting section, the first storing section, the reversing section, the second storing section, or the storing section, or Since the second detection unit and the paper discharge storage unit are housed in a single paper tray that can be taken in and out of the image forming apparatus or that is detachable, the paper feeding system is applied to the existing image forming apparatus. Thus, it is possible to easily and quickly perform image formation quickly and appropriately using used paper without complicating the user.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus to which a first embodiment of a sheet feeding system for an image forming apparatus according to the present invention is applied.

FIG. 2 is a schematic enlarged view of a separating portion shown in FIG. 1;

FIG. 3 is a schematic configuration diagram of an image forming apparatus to which a second embodiment of a sheet feeding system of the image forming apparatus according to the present invention is applied.

FIG. 4 is a schematic configuration diagram of an image forming apparatus to which a third embodiment of a sheet feeding system of the image forming apparatus according to the invention is applied.

FIG. 5 is a schematic configuration diagram of an image forming apparatus to which a fourth embodiment of a sheet feeding system of the image forming apparatus according to the present invention is applied.

FIG. 6 is a schematic configuration diagram of an image forming apparatus to which a fifth embodiment of a sheet feeding system of the image forming apparatus according to the invention is applied.

FIG. 7 is a schematic configuration diagram of an image forming apparatus to which a sixth embodiment of a sheet feeding system of the image forming apparatus according to the invention is applied.

FIG. 8 is a schematic configuration diagram illustrating an example of a sheet feeding system of a conventional image forming apparatus.

FIG. 9 is a schematic configuration diagram showing another example of a paper feeding system of a conventional image forming apparatus.

FIG. 10 is a schematic configuration diagram illustrating still another example of a sheet feeding system of a conventional image forming apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Image forming apparatus 101 Paper feeding system section 102 Image forming section 103 Used paper 104 Paper feeding tray 105 Detecting section 106 Separating section 107 First storing section 108 Second storing section 109 Inverting section 110, 111 Transport roller 112 Switching plate 113 Storage-side transport path 114 Reverse-side transport path 115 to 130 Transport roller 200 Image forming device 201 Paper feed system 202 to 205 Transport roller 206 Storage unit 300 Image forming device 301 Paper feed system 302 Detecting unit 303 Separating unit 304, 305, 308 , 309 Transport roller 306 Discharge storage unit 307 Discharge side transport path 400 Image forming device 401 Paper feed tray 402 Paper feed system 403 Tray body 404 Detecting units 405, 406, 409 to 415 Transport roller 407 Storage unit 408 Inverting unit 500 Image Forming device 501 Paper feed tray 501a Opening 502 Paper feed system 503 Tray body 504, 505 Detection unit 506-510, 515-522 Conveyance roller 511 Storage unit 512 Separation unit 513 Inversion unit 514 Paper discharge storage unit 600 Image forming device 601 Supply Paper tray 602 Paper feed system 603 Tray body 604 Detector 605, 606 Transport roller

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F053 CA06 CA16 CA18 EA01 EB01 EC02 ED03 ED15 ED17 LA03 LB03 3F054 AA01 AC01 BA02 BB07 BB24 BF08 CA02 CA23 CA25 CA31 3F100 AA02 BA06 CA03 CA06 CA12 CA15 DA09 EA02 EA03 EA03 EA03 EA03 EA03 AB30 AB32 AB35 AC09 AC11 AC65 BA04

Claims (6)

[Claims] An image forming apparatus for conveying used paper from a paper feeding system to an image forming unit and forming an image on the used paper in the image forming unit. The placing section on which the sheet is placed, and using the one side surface of the used paper sent from the placing section as a detection surface, whether the detection surface is a non-image-formed surface or an already-image-formed surface. A detecting unit for detecting, a first storage unit for sequentially stacking and storing the used papers directly conveyed from the placement unit with the conveyed surfaces aligned, and a first storage unit sent out from the placement unit A reversing unit for reversing the front and back of the used paper, and a second storage unit for sequentially stacking and storing the used paper conveyed by being reversed and conveyed by the reversing unit, with the conveyed surfaces aligned, And based on the detection result of the detection unit, The used paper sent from the mounting unit is directly conveyed to the first storage unit, or after being inverted by the reversing unit, is conveyed to the second storage unit, and the used paper is The non-image forming surface or the already formed image forming surface is aligned and sequentially placed on the first storage unit and the second storage unit, and selectively placed from the first storage unit and the second storage unit. A sheet feeding system for an image forming apparatus, wherein a used sheet is sequentially conveyed to the image forming unit in the order in which the sheets are placed first. 2. A sheet feeding system for an image forming apparatus, wherein a used sheet is conveyed from a sheet feeding system to an image forming unit and an image is formed on the used sheet by the image forming unit. A placement unit on which a sheet is placed, and a detection unit that detects whether the image forming surface of the used paper sent from the placement unit is an unimaged surface or an already-imaged surface.
A storage unit for storing the conveyed used paper sheets sequentially stacked with the conveyed surfaces aligned and storing the used paper sheets, and conveying the used paper sheets sent from the placement unit to the storage unit by turning over the front and back of the used paper sheets And a reversing unit that performs, based on the detection result of the detection unit, directly transports the used paper sent from the placement unit to the storage unit, or after the reversing unit reverses the used paper. Transported to the storage unit, the unprinted surface or the already-imaged surface of the used paper is aligned and placed on the storage unit sequentially, and the used paper is placed first from the storage unit. A sheet feeding system for an image forming apparatus, wherein the sheet is sequentially conveyed to the image forming unit in order. 3. The paper feeding system of the image forming apparatus, wherein a surface of the used paper sent from the placement unit opposite to a surface detected by the detection unit is a non-image formation surface or an already imaged image. A second detection unit that detects whether the surface is a formation surface; and a paper discharge storage unit that sequentially places the used paper sheets whose both surfaces are already image-formed surfaces, wherein the detection unit and the second 3. The image forming apparatus according to claim 1, wherein when the detecting unit detects that both of the image forming surfaces are already formed, the used paper is conveyed to the discharge storage unit and placed thereon. Paper feeding system. 4. The paper feeding system of the image forming apparatus, wherein the used paper is placed on the placement unit with the image-formed surface facing up, and based on a detection result of the detection unit, the used image is The sheet is conveyed to the first storage unit, the second storage unit, or the storage unit in a state in which a surface opposite to a forming surface is an image forming surface in the image forming unit. A sheet feeding system for an image forming apparatus according to claim 1. 5. The detecting section sets a surface on one side of a used sheet to be sent out next among the used sheets placed on the placing section as a detecting surface, and detects the non-image-formed area. The sheet feeding system for an image forming apparatus according to any one of claims 1 to 4, wherein it is detected whether the sheet is a surface or an image-formed surface. 6. The placement unit, the detection unit, the first storage unit, the reversing unit, the second storage unit, or the storage unit, or the second detection unit, and the paper discharge The image forming apparatus according to any one of claims 1 to 5, wherein the storage unit is housed in a single paper tray that can be taken in and out of the image forming apparatus or that is detachable. Equipment feeding system.