JPH0220539B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to an image forming apparatus equipped with a sheet sorting section capable of sorting and collecting sheets such as transfer paper.
For details, see sorting and collecting sheets with images formed on them.
It is possible to perform multiple functions such as image formation on both sides of the sheet and multiple image formation on one side of the sheet, and it is also possible to perform image formation by feeding the sheets stacked on the bin tray of the sheet sorting section to the image forming section. The present invention relates to an image forming apparatus.

(b) Prior art In recent years, image forming devices such as copying machines (hereinafter referred to as copying machines) have a sheet sorting function for sorting and collecting copied sheets, a duplex function for forming images on both sides of sheets, and a duplex function for forming images on one side of sheets. There is a demand for multifunctionality such as multiple functions for multiple copying, as well as systemization. Conventionally, these multifunctions have been built into the main body of the copying machine in advance, or separate from the main body of the copying machine, such as a sorting device, duplex device, etc. It is attached to support multi-functionality.

For example, as shown in FIG. 3, the copying apparatus 1 includes a document table 2 that can slide back and forth with a document M placed thereon;
Lens system fixed to support member S of the main body of the device
LE, and two cassettes C ₁ and C ₂ on which a large number of sheets can be placed and which can be attached to and removed from the main body of the apparatus, and a cylindrical photoreceptor having a central axis extending perpendicular to the sheet surface. 3, and a developing device 5, a cleaner 6, and a charger 7 arranged near the periphery thereof are integrally arranged in a frame 9, and these photoreceptor 3, developer 5, cleaner 6, and charger 7 are connected to the main body. A unit 10 that can be freely inserted and removed from the support member S
It consists of Furthermore, a conveyance device 13 having a transfer charger 11, a separation roller 12, etc. is disposed below the unit 10, and a conveyance device 13 is provided below the unit 10.
A paper feed roller 15 and a registration roller 16 for feeding the sheets on the cassettes C ₁ and C ₂ are disposed at 3.
A fixing device 17 to which the transferred sheet is fed from the conveyance device 13 is also provided. And fuser 1
A flapper 19 for changing the sheet feeding direction is disposed at the exit portion of the copying machine 7, and the flapper 19 transfers the sheets to a sheet sorting device 2 separate from the main body 1 of the copying machine.
0 or an intermediate tray 22 disposed within the device main body 1
It is selected and fed to the conveyor belt 23 that leads to. The sheet sorting device 20 has a large number of sheet storage bin trays 25.
..., and these trays 25 can be transported up and down by a conveyor 26, and sheets are discharged and collected on a predetermined tray 25 by a paper feed roller 27. On the other hand, the intermediate tray 22 is installed at a lower position of the apparatus main body 1 and is inclined in order to ensure sheet stacking and refeeding properties. A feed roller 29 and a feed roller 30 are provided.

Based on the above configuration, when the document table 2 moves, the document M placed on the document table 2 is irradiated by the light source L, and the reflected light passes through the lens system LE and is uniformly charged by the charger 7 in advance. An electrostatic latent image is formed on the surface of the photoreceptor 3, and then, based on the rotation of the photoreceptor 3 in the direction of the arrow, the electrostatic latent image forms a toner image at the position of the developing device 5. Meanwhile, cassette C ₁
Or, the sheets loaded on C ₂ are loaded on paper feed roller 1.
5, and is aligned with the toner image on the surface of the photoreceptor by a registration roller 16, and further transferred to the sheet surface by a transfer charger 11. Furthermore, the sheet carrying the toner image is separated from the photoreceptor 3 by a separation roller 12,
The image is sent to the fixing device 17 by the conveyance device 13, and is fixed therein. In the case of single-sided copying, the flapper 19 is switched to the sheet sorting device side, and the copied sheet is ejected to a predetermined tray 25 by the paper feed roller 27, and
are moved by a conveyor 26 according to a prespecified sorting method, and the sheets are sorted in a predetermined pattern. On the other hand, in the case of double-sided copying, the flapper 19
is switched to the intermediate tray side. Therefore, the sheets copied on one side are guided to the intermediate tray 22 by the conveyor belt 23, and a predetermined number of sheets are stacked and accumulated on the tray 22. When the one-sided copying is completed, the sheet on the intermediate tray 22 is transferred to the feed roller 29.
The sheet is switched back and fed from the rear end surface by the feed roller 30, and is copied onto both sides of the photoreceptor 3 and the transfer charger 11 with the uncopied side facing upward, and then transferred to the fixing device 17 as described above. The sheets are then sent by the flapper 19 to the sheet sorting device 20, where they are sorted in a predetermined pattern.

Further, as another example of the conventional copying apparatus 1', there is one shown in FIG. The copying device 1' also includes:
Similar to the copying apparatus 1, a document table 2, a cassette
C ₁ , C ₂ , lens system LE, photoreceptor 3, developer 5,
The unit 10 includes a cleaner 6, a charger 7, a transport device 13, a fixing device 17, and the like.
Then, it branches to a path 31 from the fixing device 17,
A reversing guide path 32 having a paper feed roller 34 is provided, and a flapper 33 connects the reversing guide path 32 to the path 3 to the sheet sorting device 20'.
It can be switched to 5. Furthermore, a path 37 is installed which is guided from the reversing guide path 32 via a flapper 36, and this path 37 has a large number of discharge ports 37a.
…… According to the sheet size, the intermediate tray 2
2'. On the other hand, the sheet sorting device 20' is constructed separately from the main body of the copying apparatus 1', and is fixed to the main body of the apparatus with screws or the like. Further, the sorting device 20' has a large number of trays 25' fixed thereto, and each tray 25'...
A flapper 41 . . . and a paper feed roller 42 . . . are arranged at positions corresponding to .

Based on the above configuration, the sheet transferred by the photoreceptor 3 and fixed by the fixing device 17 is transferred to the path 31.
guided by. In the case of one-sided copying, the flapper 33 is switched to the path 35 side, and the ejection roller 39
from there to the sheet sorting device 20'. and,
Flapper 41 and paper feed roller 4 of sorting device 20'
2, sheets are stacked on a predetermined tray 25' according to a predetermined sorting method. On the other hand, in the case of double-sided copying, the flapper 33 is switched to the reversing guide path 32 side, the single-sided copied sheet sent from the path 31 is guided to the guide path 32, and then the sheet feeding roller 34
Switch the sheet by flipping the . Then, the reversed sheet is discharged by the flapper 36 to the intermediate tray 22' through the path 37,
A predetermined number of single-sided copy sheets are stored in the tray 22'. Furthermore, the sheet on the intermediate tray 22' is sent to the photoreceptor 3 portion with the non-copied side facing up by the feeding roller 29 and the sending roller 30, and is transferred to the upper surface of the sheet at this portion. The sheets that have been double-sided copied are then sent to the sheet sorting device 20' and sorted into each tray 25'.

(c) Problems to be solved by the invention Therefore, in the main body of the copying machine 1 (or a special double-sided copying machine), the special intermediate trays 22, 22'
Furthermore, it is necessary to install the intermediate tray 22 at an angle to ensure sheet loading performance, or to install a reversing mechanism such as a reversing guide path 32 outside the intermediate tray. A large dead space is created, and the double-sided copying device becomes quite large, so that the entire unit including the sheet sorting devices 20, 20' becomes a fairly large device. Furthermore, as shown in FIGS. 3 and 4, the copying device 1
When a double-sided copying device is incorporated into the main body, it is necessary to have a fairly robust structure in terms of strength as the main body becomes larger, which also causes an increase in weight.

Furthermore, when troubleshooting problems such as paper jams, paper jams can occur over a wide range of locations because the main body of the copying machine, the double-sided copying section, the sheet sorting device, and the sheet conveyance path are long and complicated.
It takes time to find the location where paper jams occur, and because the intermediate tray and conveyance section of the duplex copying device are built inside the device, the location of the paper jam cannot be seen from the outside, making it difficult to open the cover, etc. This requires a lot of work, and troubleshooting has become extremely troublesome. Furthermore, as shown in the above-mentioned conventional example, the intermediate trays 22, 22' are generally installed in the lower part of the apparatus, that is, near the floor surface, and the user must bend down to clear paper jams, which is extremely tedious. It's getting harder to use.

In addition, single-sided copied sheets are stacked on the intermediate trays 22 and 22', but these sheets often curl due to the pressure and heat received during the fixing process, so the curled sheets are When refeeding from the tray, feeding errors such as double feeding are likely to occur, which, together with the increasing size and complexity of the copying apparatus, is a factor that reduces the reliability of the entire apparatus.

Furthermore, in addition to multi-functionality and systemization of copying devices as mentioned above, there has recently been a trend toward personalization, but copying devices that meet this trend are limited by limitations such as size, weight, price, etc. There are not many functions provided, and for example, paper feeding devices are generally equipped with only a single or manual feeding function. Therefore, in such personal type inversions, mini-sorters, optional cassettes, document feeders, etc. are added according to the user's requests, but each of these devices such as mini-sorters has only a single function. If these devices are installed one after another in the main unit of the device, the unit device as a whole becomes quite large and expensive, even though the main unit is small and low-priced. The benefits are not being taken advantage of.

In addition, due to the multifunctionality and systemization of copying machines, editing, bookbinding, etc. are performed on copying machines equipped with sheet sorting functions and double-sided copying functions. Or, it is often necessary to manually copy sheets. Therefore, some copying machines have a built-in interrupt function, and some copying machines have a manual feed mechanism in the paper feed section, but if you want to interrupt the copying machine during editing, bookbinding, etc., you need to Copies can only be made using sheets of the copy size set in the copying device, and copies cannot be made if the magnification, copy size, or type of sheet is different, which is very inconvenient. Note that copying machines equipped with multiple paper feed devices or manual feed mechanisms can accommodate different magnifications, copy sizes, sheet types, etc.; however, copying machines equipped with such functions are large and The copying apparatus is expensive, and the number of users who can use the copying apparatus is limited. In addition, in a copying machine that does not have such a function, when an interrupt is made, it is necessary to perform the complicated work of replacing the set sheet or repeating manual paper feeding for the required number of sheets.

Further, when the copying apparatus is actually used, the type and number of sheets may be managed, for example, for each department. In that case, if there are few departments using it,
It is sufficient to place paper feed cassettes dedicated to each department in parallel in the copying machine in advance, but if there are many departments and many types of sheets are used,
It has become impossible to place a dedicated paper feed cassette in parallel with the copying machine in advance. Therefore, it is conceivable to configure the copying apparatus so that a large number of copying apparatuses can be installed, but this is not practical because it inevitably increases the size and weight of the apparatus, complicates the mechanism, and increases the price.

(d) Means for Solving the Problems The present invention aims to solve the above-mentioned problems, and includes an image forming section and a large number of sheet storage bin trays, and has an image forming section and a large number of sheet storage bin trays. In an image forming apparatus equipped with a sheet sorting section capable of sorting and collecting sheets, at least one of the bin trays functions as a sheet refeeding section to refeed the sheets guided to the bin tray. and a sheet reversing means capable of reversing sheets fed into the bin tray so that at least one of the bin trays other than the bin tray functioning as the sheet refeeding section functions as a sheet reversing section. a conveying path communicating the sheet reversing means and the sheet refeeding means; and a sheet conveying means conveying the sheet fed by the sheet refeeding means or the sheet reversing means to the image forming section. , wherein at least the bin tray serving as the sheet refeeding section and the sheet reversing section among the bin trays is configured such that a large number of sheets can be placed on the bin tray from the rear of the bin tray, and the sheet refeeding section The feeding means and the sheet reversing means are capable of feeding the sheets placed on the bin tray, and in the non-feeding state, the sheet discharging means onto the bin tray from the front or from the rear. If the sheet refeeding means or the sheet reversing means is retracted to a position that does not interfere with the placement of sheets, and a sheet from the rear is placed on the bin tray, the sheet refeeding means or the sheet reversing means is activated to form an image. This apparatus is characterized in that the sheet feeding operation is performed by a switch.

(e) Operation Based on the above-mentioned configuration, the sheet sorting section sorts and stacks sheets into each bin tray according to a predetermined pattern, and the image forming section collects sheets with one side copied in the bin tray, and then the sheets are collected from the bin tray. The sheet is re-fed by the sheet feeding means, and if necessary, the sheet is sent to a bin tray that serves as a sheet reversing section to be reversed, and then the sheet is fed again to the image forming section by the sheet transporting means to perform double-sided copying and single-sided multiple copying. Performs multi-functional processing. Further, the bin tray is used as a paper feeding device, and a sheet is fed from the bin tray by a sheet feeding means, and further fed to an image forming section by a sheet carrying means to make a new copy.

(f) Examples Examples of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the copying apparatus U has a copying apparatus main body 50 that constitutes a copying section (image forming section), and the apparatus main body 50 includes a document table 2, a light source L,
The apparatus includes a lens system LE and two cassettes C ₁ and C ₂ , and a cylindrical photoreceptor 3 is disposed within the apparatus main body 50 . Further, near the periphery of the photoreceptor 3, two developing devices 5 and 5' each containing toner of a different color, a cleaner 6 and a primary charger 7 are installed at the tip of the conveying device 13. A transfer charger 11 and a separation roller 12 are provided. Further, paper feed rollers 15, 15 are disposed in the cassettes _C1 , _C2 , and are guided by a pair of registration rollers 16 via paths, respectively.
It is guided to the pair of registration rollers 16 via a path from a guide port 53 opened on the lower surface of the apparatus main body 50 . Further, a fixing device 17 is disposed at the rear end portion of the conveying device 13, and a pair of discharge rollers 56 are disposed in the fixing device 17 to discharge the sheet to the outside of the machine. sensor to detect
S _p is installed.

On the other hand, the sheet sorting section 57 and the sheet conveying section 59
A sheet stacking device 60 consisting of
It is placed facing the. A large number of sheet storage bin trays 61 ₁ to 61 _o are installed in the sheet sorting section 57, and upper and lower pulleys 115 and 116 are rotatably arranged.
A belt 117 is wound around 5,116.
Furthermore, as shown in detail in FIG.
₁ to 121 _o are arranged at a predetermined interval so as to be elastically pressed against the belt and follow the rotation, and a guide plate 122 is arranged between these rollers to form a sheet conveyance path 123. ing. Furthermore, a path 125 for receiving sheets from the pair of ejection rollers 56 of the copying apparatus main body 50 extends so as to communicate with the transport path 123, and facing the transport path 123, a path 125 extends in the direction of each of the trays 61 ₁ to 61 _o . Numerous flappers ₁₂₆ that can select and branch sheets
-126 _o are rotatably supported on the spindles of the respective conveyance rollers 121 ₁ -121 _o . It should be noted that each flapper 126 is switched by a spring to a solid line position in which the sheet restricts the intrusion of the sheet toward the tray and guides the sheet to a path 123 along the belt 117, and to a chain line position in which the sheet is guided to a tray path 132 by energizing the solenoid 131. Note that a sheet detection sensor 133 consisting of a light emitting element 133a and a light receiving element 133b is installed in each of the trays 61 ₁ to 61 _o .
Arms 150 ₁ to 150 _o are rotatably supported on the spindles of the respective conveyance rollers 121 ₁ to 121 _o , and a feeding roller 151 ₁ is attached to the tip of the arm.
151 _o are provided, and a clockwise biasing force is applied by a torsion coil spring (not shown) to bias the feeding roller to a position away from the top of the tray. Note that these feeding rollers 151 ₁ to 151 _o are respectively conveying rollers 121 ₁
~121 _o through a chain or gear train (not shown), and the transport rollers 121 ₁ ~1
The sheet on the _tray can be rotated in a direction to send out the sheet to the conveyance path 123 in synchronization with the rotation of the conveyance path 123. On the other hand, each of the trays 61 ₁ to 61 _o has an auxiliary plate 153 rotatably supported by a pin 152 on its bottom surface, and further below these auxiliary plates 153 are back-up links 155 ₁ to 155 _o . is the spindle 156...
It is rotatably supported by... One end arm of the back up links 155 ₁ to 155 _o and the feeding roller support arm 150 ₁ to 150 _o
are connected via links 157 ₁ to 157 _o , respectively, and the arm 150 is connected downward (counterclockwise).
When the back up link 155 is rotated upward (clockwise), the back up link 155 is rotated upward (clockwise). Furthermore, solenoids 159 ₁ to 159 _o are connected to one end arm portion of each back up link 155 ₁ to 155 _o , and feeding rollers 151 ₁ to 151 _o and the auxiliary plate 153 are fed by excitation of the solenoids. position (see the lowermost tray 61 _o part in FIG. 2). Further, a drive source such as a motor is directly connected to the shaft to which the lower pulley 116 is fixed, and the drive source also serves as a drive source for the sheet conveying section 59 at the same time. The sheet conveyance unit 59 has a conveyance path 141 that is aligned with a discharge path 144 extending from a conveyance path 123, and the path 141 includes a large number of conveyance rollers driven by a gear train or chain from a drive source. Pairs 142 ₁ to 142 ₄ and guide plates 143 ₁ to 143 ₄ between them are arranged. In addition,
Among these pairs of conveyor rollers, the intermediate conveyor roller pair 1
42 ₃ and 142 ₄ are so-called oblique rollers, which are configured to correct the position of the sheet in a direction perpendicular to the sheet conveyance direction with respect to a reference, and the final conveyance roller 142 ₄ is a skew roller. It is aligned with the guide port 53 of 50. Furthermore,
A third cassette _C3 can be attached to the other end of the sheet conveying section 59, and is guided from the third cassette _C3 through a path 145 to a final conveying roller pair ₁₄₂₄ by a paper feed roller 15'. .

Next, the operation of this embodiment will be explained.

First, copy the m-page document onto both sides of the sheet,
The case of producing n copies of double-sided copy sheets will be explained.

When the operator instructs double-sided copying of the number n of sheets and operates the start switch of the copying apparatus main body 50, the first page of the document placed on the document table 2 is transferred to the apparatus main body 50.
The sheet is copied and introduced into the path 125 of the sheet stacking device 60 from the discharge roller pair 56. On this occasion,
When the sheet detection sensor S _p located near the discharge roller pair 56 in the fixing device 17 detects the passage of the leading edge of the sheet, the sensor signal is input to a microprocessor unit (hereinafter abbreviated as MPU) and
A signal to excite the solenoid of the first stage flapper 126 ₁ is output from the MPU, and the first stage flapper 126 1 is energized.
₁ is switched and held at the position shown by the chain line in _FIG . Therefore, the first sheet is transported by the belt 117 and the conveyor rollers 119, 120.
The first stage flapper 126 ₁
is guided through the tray path 132 ₁ and discharged onto the first tray 61 ₁ . Next, when the second sheet is detected by the detection sensor S _p , the first
_The second stage flapper 135 ₁ is _returned to the solid line position in FIG.
32 is switched and held in a position communicating with ₂ . As a result, the second sheet is ejected to the second tray 61 ₂ in the same way as the first sheet. Similarly below,
The third sheet is discharged to the third tray 61 ₃ , and the nth sheet is discharged to the nth tray 61.
It is discharged to _o . Then, when you replace the original with the second page on the original platen 2 and start copying,
First, all the flappers 126 ₁ to _{126 o} are returned to the solid line positions in FIG. The first stage solenoid 159 ₁ is energized and rotates the back up link 155 ₁ clockwise to release the auxiliary plate 15 .
At the same time, the arm 150 ₁ is rotated counterclockwise via the link 157 ₁ to bring the feeding roller 151 ₁ into contact with the sheet on the tray 61 ₁ . Accordingly, the sheet is sent to the conveyance path 123 by the rotation of the feed roller 151 ₁ , is further guided to the sheet conveyance section 59 through the conveyance path 144 , and is further copied by the conveyance roller pairs 142 ₁ to 142 ₄ of the conveyance section 59 . It is guided to the guide port 53 of the device main body 50. and,
The copying apparatus main body 50 copies the second page of the original on the uncopied side, and the double-sided copied sheet is sent from the discharge roller pair 56 to the sheet stacking device 60 . At this time, sheet detection sensor 1
33a and 133b detect that the sheet has been ejected from the first tray ₆₁₁ , the solenoid ₁₅₉₁ is de-energized and the feeding roller 15
1 is returned to the normal position where ₁ is located above and the auxiliary plate 153 is located below, and the detection sensor S _p
Based on the sheet passage detection by , the first stage flapper 126 ₁ is held so as to guide it to the tray side path 132 ₁ . Therefore, the double-sided copied sheet is guided by the flapper 126 ₁ and discharged onto the first tray 61 ₁ . At the same time, the second tray 61 ₂
The uncopied side of the second sheet stacked above is copied, and the second sheet with both sides copied is discharged and stacked on the second tray ₆₁₂ . At the same time, the n-th double-sided sheet is discharged and stacked onto the n-th tray _61o . below,
Copying from the 3rd page to the mth page is also performed repeatedly in the same way as the double-sided copying of the 1st and 2nd pages, and finally n copies of the double-sided copy sheet of page m are placed in each tray 61 ₁ - 61 _o , and all copying operations are completed.

Next, a case of performing multiple copying in which multiple images are overlapped and copied on one side of a sheet will be described.

As in the case of double-sided copying, first, a sheet with the first original copied on one side is discharged and stacked on the first tray ₆₁₁ . Then, when the second original is placed on the document table 2 and the start switch is activated to make multiple copies, the first stage flapper ₁₂₆₁ is switched to the position indicated by the chain line in Figure 2, and the first stage solenoid 159 ₁ is excited and lifts up the auxiliary plate 153 of the first tray 61 ₁ and feed roller 151 ₁
The sheet on the tray 61 ₁ is thus fed to the conveyance path 123 . Simultaneously with the actuation of the start switch, the nth stage flapper _126o is switched to the position for guiding the sheet to the tray path _132o ,
Therefore, the sheet conveyed by the belt 117 along the conveyance path 123 is discharged and collected onto the tray _61o by the nth stage flapper _126o . When the sheet detection sensor 133 detects that the sheet has been accumulated on the n-th tray 61 _o , the n-th solenoid 159 _o (not shown) is energized and the back up link 155 _o is activated. The auxiliary plate 153 is lifted by the arm 150 _o
descends and brings the feeding roller _151o into contact with the sheet on the tray _61o , specifically the auxiliary plate 153, and sends the sheet to the conveyance path 123, whereby the sheet is reversed once and its copy side is The sheet is sent out from a switchback path 144 to a conveying path 141 of the sheet conveying section 59 with the rear end facing downward (switchback). Then, the single-sided copy sheet is guided to the guide port 53 of the copying apparatus main body 50 by each of the transport rollers 142 ₁ to 142 ₄ of the sheet transport section 59, and
The second original is superimposed and copied on the side that is being copied at 0. Furthermore, similarly to double-sided copying, the multiple-copied sheets are discharged and stacked on the first tray ₆₁₁ .

Note that in the above explanation, when multiple copies are made, the first
Tray 61 ₁ (top stage) and nth stage (bottom stage)
However, it goes without saying that other trays may be used.

Next, unused sheets are placed in the bin trays 61 ₁ to 6.
1 _o to the copying apparatus main body 50 and use the bin tray as a paper feeding device will be described.

An operator loads unused sheets onto a bin tray 61 predetermined by each department, for example, the bottom bin tray 61 _o from the rear of the tray. At this time, the bin tray 61 _o has the solenoid 159 _o in a de-energized state, the back up link 151 _o is located below, and the feeding roller 1
51 _o is located above, and the feeding roller and the auxiliary plate 153 do not get in the way of sheet stacking. An instruction for single-sided copying using a sheet from the bin tray is given, and the start switch of the copying apparatus main body 50 is activated. Then, the flapper _126o is returned to the position shown by the solid line in FIG.
Next, the n-th stage solenoid 159 _o is energized and rotates the back up link 155 _o clockwise to lift up the auxiliary plate 153 .
_The arm _150o is rotated counterclockwise via the arm 150o to bring the feeding roller _151o into contact with the sheet on the tray _61o . In this state, when the feeding roller 151 _o is rotated, the sheet on the bin tray 61 _o is fed in the direction of the conveying roller 121 _o , and then
21 _o and sent out to the conveyance path 123. Then, the sheet is sent to the conveyance path 144 by the belt 117 and guided to the sheet conveyance section 59, and further conveyed by the conveyance roller pairs 142 ₁ to 142 of the conveyance section 59.
142 ₄ to the guide port 53 of the main body 50 of the copying apparatus. Then, the original placed on the original platen 2 is copied by the copying apparatus main body 50 and introduced into the path 125 of the sheet stacking device 60 from the discharge roller pair 56 . At this time, when the passage of the leading edge of the sheet is detected by the sheet detection sensor S _p located near the discharge roller pair 56, the sensor signal is input to the MPU,
A signal to excite the solenoid of the first stage flapper 126 ₁ is output from the MPU, and the flapper 126 1 is activated.
6 ₁ is switched and held at the position shown by the chain line in FIG. 2, which communicates with the tray side path 132 ₁ side. Therefore, the copied sheet is transferred to the belt 117 and the conveyor rollers 119, 1.
20, and is further conveyed by the first stage flapper 12.
6 ₁ through the tray path 132 ₁ .
It is discharged and collected on the stage tray ₆₁₁ . In addition,
If necessary, the single-sided copy sheets can be sorted into the respective bin trays 61 ₁ to 61 _o-1 according to a predetermined pattern based on the sheet sorting function of the sheet sorting section 57 described above. Furthermore, in the above explanation, unused sheets are stacked on the bottom bin tray 61 _o , but the stack is not limited to the bin tray 61 _o , and the maximum n of the bin trays 61 ₁ to 61 _o
- Can be arbitrarily selected and stacked on one bin tray. At this time, the copied sheets are discharged and stored in a bin tray that is not loaded with unused sheets. In addition, the bin trays 61 ₁ to 61 _o
It is also possible to feed paper from a cassette by disposing a cassette holding member in a portion of the cassette.

(G) Effects of the Invention As described above, according to the present invention, the sheet storage bin tray of the sheet sorting section 57 includes the sheet conveying means 117, 142 ₁ to 142 ₄ for conveying sheets from the sorting section 57 to the image forming section 50. 61 ₁ ~ 6
A bin tray that faces at least one of the bin trays and is provided with sheet refeeding means 151 ₁ to 151 _o capable of refeeding the sheets collected in the bin tray _, and that functions as the sheet refeeding section. Since the sheet reversing means is arranged so that at least one of the bin trays other than the above bin trays functions as a sheet reversing section, it is equipped with multiple functions such as a double-sided copying function and a multiple copying function in addition to the sheet sorting function. However, it does not require the intermediate tray and reversing path that were conventionally required, and the dead space caused by these intermediate trays and reversing path can be reduced, making it possible to significantly downsize and reduce the structure. It is possible to simplify and reduce the weight, and it can be manufactured at low cost. In addition, since the sheet sorting function, double-sided copying function, and multiple copying function can be used in common with the bin trays 61 ₁ to 61 _o , the flow of sheets can be easily checked from the outside, and sheet jams and other problems can be prevented. Trouble handling work can be made almost the same for each function, and the handling work itself can be simplified, improving usability. Furthermore, the sheet classification section 5
7 bin trays 61 ₁ to 61 _o to sheet conveyance path 123 and sheet conveyance means 117, 142 ₁ to 1
Since the sheet is fed to the image forming unit 50 via 42 ₄ , it is possible to place the sheet conveyance path and other areas where sheet jams are likely to occur at a relatively upper position, and the feeding means ensures that the sheet is The reliability of the image forming apparatus U itself can be improved, and the usability can be further improved. In addition, it can be easily added to the main body of a personal image forming (copying) device.
The image forming apparatus U according to the present invention can be equipped with multiple functions, and can be multifunctional while taking advantage of the advantages of a personal machine.

In particular, each bin tray 61 ₁ of the sheet sorting section 57
~661 By using _o as a feeding device,
Even when editing or binding is in progress on the copying machine itself,
It is possible to easily copy sheets with different magnifications, copy sizes, sheet types, etc., and since up to n-1 bin trays can be used as paper feeders, the sheets to be used can be separated by department. Even when using a large number of types of sheets, sheet management can be performed extremely easily.

[Brief explanation of drawings]

1 and 2 are diagrams showing an embodiment according to the present invention, in which FIG. 1 is an overall front view, and FIG. 2 is a front view showing a sheet sorting section of a sheet stacking device. 3 and 4 are overall front views showing different conventional examples, respectively. U... Image forming device (copying device), 50... Image forming section (copying device main body), 57... Sheet sorting section, 59... Sheet transport section, 60... Sheet stacking device, 61 ₁ to 61 _o ... ...seat storage bin tray,
117,142 ₁ to 142 ₄ ... sheet conveying means,
123...Conveyance path, ₁₂₆₁ to _126o ...Flapper, ₁₅₁₁ to _151o ...Sheet refeeding means,
Sheet reversing means.

Claims (1)

[Scope of Claims] 1. It has an image forming section and a large number of sheet storage bin trays, and is capable of sorting and sorting sheets from the image forming section.
In an image forming apparatus comprising a sheet sorting unit that can be stacked, the sheet refeeding unit refeeds the sheets guided to the bin tray so that at least one of the bin trays functions as a sheet refeeding unit. a sheet reversing means capable of reversing a sheet fed into the bin tray so that at least one of the bin trays other than the bin tray functioning as the sheet refeeding section functions as a sheet reversing section; a conveying path that communicates the reversing means and the sheet refeeding means; and a sheet conveying means that conveys the sheet fed by the sheet refeeding means or the sheet reversing means to the image forming section, Of the bin trays, at least the bin tray serving as the sheet refeeding section and the sheet reversing section is configured such that a large number of sheets can be placed on the bin tray from the rear of the bin tray, and the sheet refeeding means and The sheet reversing means is capable of feeding the sheets placed on the bin tray, and in a non-feeding state, the sheet reversing means is capable of feeding the sheets onto the bin tray from the front or from the rear by the sheet discharging means. When a sheet from the rear is placed on the bin tray, the sheet refeeding means or the sheet reversing means is set to feed the sheet by using an image forming start switch. An image forming apparatus configured to operate.