JP2001042748A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove stacked sheets and to smoothly restart an image forming operation by temporarily interrupting the image forming operation when the stacked amount of the sheets stacked on both upper and lower trays reaches the maximum amount, removing all the sheets in either one tray, then raising the upper tray, and thereby restarting the image forming operation. SOLUTION: When both upper and lower trays 292 and 293 reach the maximum stack amount in the midst of stacking the sheets P in the tray 292, the image forming operation for the new sheet P is temporarily interrupted and the ejection of the sheet P is stopped (a). The tray 292 is moved to the position of a processing tray being the start position at the time of restarting (b). When the sheet P in the tray 292 is removed by a user (c), the image forming operation is restarted as it is (d). When the sheet P is removed from the tray 293 (e), the tray 292 is raised from the start position and the tray 293 is moved to the start position so as to restart the image forming operation (f).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus using, for example, an electrophotographic system and an image forming apparatus with improved control of a sheet processing apparatus connected thereto. .

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a digital copying machine having a memory for storing a plurality of image data, such as a hard disk, a document image of an entire copy job is stored in a memory, and the copy job is stored in the memory. 2. Description of the Related Art There is known an image forming apparatus having an electronic sort function for reading out image data in order from the first output image to form an image and performing image forming processing for a desired number of copies.

If this electronic sort function is used, the sheets are sorted one by one at the time when the sheets are discharged from the image forming apparatus main body. Therefore, after the discharge, the sheet is processed using a sheet processing apparatus having a plurality of trays. This eliminates the need to sort the documents one by one on the tray. Therefore, a desired number of copies can be directly stacked on the same tray.

Further, since the amount of sheets loaded on the same tray is limited, there has been proposed a sheet processing apparatus having two vertically movable trays.

[0005]

However, in the conventional image forming apparatus, when the sheets stacked on both the upper and lower trays reach the maximum stacking amount, the image forming operation by the image forming means is stopped. After the sheet is stopped, the sheet is removed from any of the trays, and then the corresponding tray is moved to the start position where the sheet is conveyed. Since the sheets were conveyed to the trays, it was inconvenient to remove the sheets when both trays reached the maximum stacking capacity, especially for the lower tray, and to move the tray from which the sheets were removed to the start position. In some cases, the movement amount is large and a time until image formation is restarted, and the function of the apparatus may be reduced.

According to the present invention, when the upper and lower trays of the sheet processing apparatus reach the maximum loading capacity and the image forming operation by the image forming means is stopped, the sheet can be easily taken out and the image forming operation can be performed. It is an object of the present invention to provide an image forming apparatus capable of promptly restarting.

[0007]

The invention according to claim 1 is
An upper tray, a lower tray, and a lower tray for driving the upper and lower trays.
Lower tray drive means, upper and lower sheet transport means for transporting sheets to the upper and lower trays, and upper and lower load quantities for respectively detecting the loading capacity of the sheets loaded on the upper and lower trays A sheet processing apparatus having a detecting unit; an image forming unit configured to form an image on a sheet based on image information; a discharging unit configured to discharge a sheet formed by the image forming unit to the sheet processing apparatus; When the stacking amount detecting unit detects that the sheet stacking amount on the upper and lower trays has reached the maximum stacking amount, the image forming operation by the image forming unit is temporarily controlled. Control means for interrupting and controlling to resume the remaining image forming operation after all the sheets stacked on one of the upper and lower trays are removed. Wherein, when said control means has suspended the image forming operation, and controls the on driving means so as to increase the upper tray to a predetermined position.

According to a second aspect of the present invention, when the image forming operation of the image forming means is temporarily interrupted during loading on the upper tray, the predetermined position at which the upper tray rises is determined by the upper position where the sheet is conveyed. It is the starting position of the tray.

According to a third aspect of the present invention, when the image forming operation is temporarily interrupted during the stacking on the lower tray, the predetermined position at which the upper tray rises is higher than the starting position of the upper tray at which sheets are conveyed. It is the upper position.

According to a fourth aspect of the present invention, the control means includes:
When sheets are removed from the upper tray after the two trays reach the maximum loading capacity and the image forming operation of the image forming unit is temporarily interrupted during loading on the upper tray, the two trays are kept in the same position. The image forming operation of the image forming means is restarted, and the sheet is conveyed to the upper tray.

According to a fifth aspect of the present invention, the control means includes:
When sheets are removed from the lower tray after the two trays reach the maximum loading capacity and the image forming operation of the image forming unit is temporarily interrupted while being loaded on the upper tray, the upper tray is raised from a start position. Then, the lower tray is moved to a start position, the image forming operation of the image forming unit is restarted, and the sheet is conveyed to the lower tray.

According to a sixth aspect of the present invention, the control means includes:
When sheets are removed from the upper tray after the two trays reach the maximum loading capacity and the image forming operation of the image forming unit is temporarily interrupted during loading on the lower tray, the lower tray is lowered, and The upper tray is moved to a start position, the image forming operation of the image forming unit is restarted, and the sheet is conveyed to the upper tray.

According to a seventh aspect of the present invention, the control means includes:
When sheets are removed from the lower tray after the two trays reach the maximum load capacity and the image forming operation of the image forming unit is temporarily interrupted while the lower tray is being loaded, the lower tray is moved to a start position. Then, the image forming operation of the image forming unit is restarted, and the sheet is conveyed to the lower tray.

[Operation] Based on the above configuration, the conveyed sheets are stacked on one of the upper and lower trays which can be moved up and down, and when the sheets on both trays reach the maximum stacking amount, image formation is performed. The image forming operation of the unit is suspended, and the upper tray is raised to a predetermined position. As a result, the sheets stacked on the upper and lower tiers can be easily taken, and the processing can be smoothly continued by reducing the amount of movement of the tray when the job is restarted, thereby improving the operability of the user and the functions of the apparatus. .

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a digital copying machine will be described as an example of an image forming apparatus according to the present invention.

FIG. 1 is a block diagram showing a configuration of a digital copying machine according to an embodiment of the present invention.

The reader unit 1 reads an image of a document and outputs image data corresponding to the document image to the image memory unit 3.

The printer section 2 records an image corresponding to the image data from the image memory section 3 on recording paper. The image memory unit 3 compresses the image data transferred from the reader unit 1, stores the compressed image data, expands the stored compressed image data, and stores the expanded image data. Transfer to the printer unit 2.

In this block diagram, a CPU 171 controls the reader unit 1, the printer unit 2, and the image memory unit 3 and notifies the sheet processing apparatus 290, which is a sheet discharging processing apparatus, via an I / F 281 in FIG. I do. CPU
Reference numeral 282 controls the sheet processing apparatus 290, and includes a load amount detection unit (load amount detection unit) 284a, 284.
An instruction to drive the tray is issued to the tray driving units (tray driving means) 283a and 283b based on the amount of sheets loaded on the tray detected by b. Also, I / F2
Via 85, information such as the stacking amount of sheets is notified.

FIG. 2 is a sectional view showing a digital copying machine according to the present invention.

In the figure, reference numeral 200 denotes a digital copying machine main body, and reference numeral 6 denotes an automatic document feeder (DF). Reference numeral 201 denotes a platen glass as a document placing table, and 202 denotes a scanner, which includes a document illumination lamp 203, a scanning mirror 204, and the like. The scanner 202 is reciprocally scanned in a predetermined direction by a motor (not shown), and the reflected light of the original is
The light is transmitted through the lens 207 through to 206 and forms an image on the CCD sensor in the image sensor unit 208. Reference numeral 209 denotes an exposure control unit including a laser, a polygon scanner, and the like.
The photosensitive drum 211 is irradiated with a laser beam 219 that is converted into an electric signal by the image sensor unit 208 and modulated based on an image signal on which predetermined image processing described below has been performed.

Around the photosensitive drum 211, a primary band dragon device 212, a developing device 213, a transfer charger 216, a pre-exposure lamp 214, and a cleaning device 215 are provided. In the image forming section (image forming means) 210, the photosensitive drum 211 is rotated by a motor (not shown) in the direction of the arrow shown in the figure, and after being charged to a desired potential by the primary charger 212, exposure control is performed. Laser light 2 from unit 209
Irradiation is performed to form an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum 211 is developed by the developing device 213 and is visualized as a toner image.

On the other hand, pick-up rollers 225, 226, and 2 from the right cassette deck 221, the left cassette deck 222, the upper cassette 223, or the lower cassette 224.
Sheets P fed by the printers 27 and 228 are sent to the main body by feed rollers 229, 230, 231, and 232,
The toner image fed to the transfer unit by the registration roller 233 and visualized is transferred to a sheet by the transfer charger 216. After the transfer, the photosensitive drum 211 is cleaned of residual toner by a cleaner device 215 and the pre-exposure lamp 2
14 erases the residual charge. The sheet after transfer is
Separated from the photosensitive drum by a separation charger 217,
The sheet is sent to the fixing device 235 by the conveyor belt 234. In the fixing device 235, the sheet is fixed by pressure and heat.
The sheet is discharged out of the main body 200 by the discharge roller 244.

The main body 200 is equipped with a deck 250 capable of storing, for example, 4000 sheets. The lifter 251 of the deck 250 rises according to the amount of the sheet so that the sheet always contacts the pickup roller 252, and the sheet is sent to the main body by the sheet feeding roller 253. In addition, a multi-bypass tray 254 capable of storing 100 sheets is provided.

Further, in FIG. 2, reference numeral 237 denotes a paper discharge flapper, which switches the path between the transport path 238 and the discharge path 243. Reference numeral 240 denotes a lower conveyance path, which guides the sheet sent from the sheet discharge roller 236 to a re-feeding path 241 by turning over the sheet through a reversing path 239. Sheets fed from the left cassette deck 222 by the feed rollers 230 are also guided to the refeed path 241. Reference numeral 242 denotes a re-feed roller that re-feeds the sheet to the image forming unit 210. 244 is disposed near the discharge flapper 237,
A discharge roller for discharging the sheet switched to the discharge path 243 side by the discharge flapper 237 to the outside of the apparatus.

At the time of double-sided recording (double-sided copying), the discharge flapper 237 is raised, and the copied sheet is guided to the re-feeding path 241 via the transport path 238, the reversing path 239, and the lower transport path 240. At this time, all the trailing edge of the sheet comes out of the conveyance path 238 by the reversing roller 245, and is pulled into the reversing path 239 to a position where the sheet is bitten by the reversing roller 245. Send to 240. When the sheet is inverted and discharged from the main body, the discharge flapper 237 is raised upward, and the sheet is pulled into the reversing path 239 by the reversing roller 245 to a position where the rear end of the sheet remains in the conveyance path 238, and the reversing roller 245 is rotated in reverse. Then, the sheet is turned over and sent out to the discharge roller 244 side.

Reference numeral 290 denotes a sheet processing apparatus for closing and aligning the sheets discharged from the image forming apparatus 200, and stacks and discharges the sheets discharged one by one on a processing tray 270. When the discharge of one copy of image formation is completed, the sheet bundle is stapled by the stapler 294 as necessary, and the upper tray 292 or the lower tray 2 serving as a discharge tray.
The bundle is discharged to 93.

The sheet P carried into the sheet processing apparatus 290 is conveyed to the upper tray 292 via the sheet conveying path 271 to perform the sheet processing when sheet processing such as alignment, stapling, and sorting is not performed. In some cases, the sheet may be conveyed to the processing tray 270 via the sheet conveying path 272.

The paper discharge trays 292 and 293 are controlled to move up and down by the motors of the tray driving units 283a and 283b shown in FIG. 1 so that they are located at the processing tray 270, which is the start position, before the image forming operation starts. Then, when the discharged sheets are stacked, the sheet moves so that the height of the sheet becomes the position of the processing tray 270. Further, the discharge trays 292 and 293 can load up to about 2000 sheets, and when one of the trays reaches the maximum amount, the height of the sheet surface is processed so as to load the other tray. It is moved to the position of the tray 270. 291
Denotes a paper tray on which separator sheets to be inserted between the discharged sheets are stacked, and 295 denotes a Z-folding machine that Z-folds the discharged sheets. Reference numeral 296 denotes a bookbinding machine that performs bookbinding by folding the center of one set of discharged sheets and performing stapling. The bound sheet bundle is discharged to a discharge tray 297.

FIG. 3 is a control block diagram of the digital copying machine 200.

Reference numeral 171 denotes a CPU for performing basic control of the digital copying machine 200.
The OM 174, a work RAM 175 for performing processing, and an input / output port 173 are connected by an address bus and a data bus. The input / output port 173 is connected to various loads (not shown) such as a motor and a clutch, which control the digital copying machine 200, and inputs (not shown) such as sensors for detecting the position of the sheet. The CPU 171 executes the RO
In accordance with the contents of M174, input / output control is sequentially performed via the input / output port 173 to execute an image forming operation.
An operation unit 172 is connected to the CPU 171, and controls a display unit and a key input unit of the operation unit 172. The operator instructs the CPU 171 to switch the display between the image forming operation mode, the scanner reading mode, and the print output mode through the key input unit.
Reference numeral 71 indicates the state of the digital copying machine 200 and the operation mode setting by key input. The CPU 171 is connected to an image processing unit 170 that processes a signal converted into an electric signal by the image sensor unit 208 and an image memory unit 3 that stores a processed image.

Next, the details of the image processing section 170 will be described with reference to FIG. FIG. 4 is a block diagram of the image processing unit.

The original image formed on the CCD sensor via the lens 207 is input as Black luminance data, and is converted into an analog dragon signal by the CCD sensor. The converted image information is input to an analog signal processing unit (not shown), and after sample and hold, dark level correction, and the like are performed, the A / D conversion unit 501 performs analog-to-digital conversion (A / D conversion). Then, the digitized signal is subjected to shading correction (correction of variations in a sensor for reading a document and light distribution characteristics of a document illumination lamp). After that, it is sent to the log converter 502.

The log converter 502 stores an LUT for converting the input luminance data into density data, and outputs a table value corresponding to the input data, thereby converting the luminance data into density data. Convert. After that, the image is scaled to a desired magnification by the scaling unit 503 and input to the γ correction unit 504. γ correction unit 5
In step 04, when outputting the density data, conversion is performed by an LUT in consideration of the characteristics of the printer, and the output is adjusted according to the density value set by the operation unit. After that, the binarization unit 5
05. The binarization unit 505 binarizes the multi-value density data, and the density value becomes “0” or “255”. The 8-bit image data is binarized and converted into 1-bit image data of “0” or “1”, and the amount of image data stored in the memory is reduced.

However, when the image is binarized, the number of gradations of the image is changed from 256 gradations to two gradations. Therefore, binarization of image data having a large number of halftones such as a photographic image generally causes deterioration of the image. Remarkable. Therefore, it is necessary to perform pseudo halftone expression using binary data. Here, an error diffusion method is used as a method for pseudo-halftone expression using binary data. According to this method, when the density of a certain image is larger than a certain threshold value, it is determined that the density data is “255”. When the density is less than a certain threshold value, it is determined that the density data is “0”. In this method, the difference between the data and the binarized data is distributed to surrounding pixels as an error signal.
The distribution of the error is performed by multiplying the weighting coefficient on the matrix prepared in advance by the error generated by the binarization, and adding the result to surrounding pixels. As a result, the density average value of the entire image is stored, and the halftone can be represented in a pseudo binary manner. The binarized image data is sent to the image memory unit 3, where the image is stored.

The image data from the computer input from the external I / F processing section 4 is processed as binary image data by the external I / F processing section, and thus sent to the image memory section 3 as it is. . The image memory unit 3
It has a high-speed page memory and a large-capacity memory (hard disk) capable of storing a plurality of page image data. The plurality of image data stored in the hard disk are output in an order according to the editing mode specified by the operation unit of the digital copying machine 200. For example, in the case of sorting, the images of the document bundle read from the DF 6 are sequentially output. The image data of the document once stored is read from the hard disk, and this is repeated a plurality of times and output. Thereby, it can play the same role as a sorter having a plurality of bins.

The image data output from the image memory unit 3 is sent to a smoothing unit 506 in the printer unit 2. The smoothing unit 506 performs data interpolation so that the line ends of the binarized image are smoothed, and outputs image data to the exposure control unit 209. Exposure control unit 209
Then, the image data is formed on the sheet by the above-described processing.

Next, details of the image memory unit 3 will be described with reference to FIG.

The image memory unit 3 writes a binary image from the external I / F processing unit 4 and the image processing unit 170 via a memory controller unit 302 to a page memory unit 301 formed by a memory such as a DRAM. External I / F
The processing unit 4 reads out an image to the printer unit 2 and accesses the hard disk 304 as a large-capacity storage device for inputting and outputting an image. The memory controller 302
A DRAM refresh signal for the page memory 301 is generated, and the external I / F processing unit 4, the image processing unit 17
0, page memory 301 from hard disk 304
Arbitrate access to.

Further, in accordance with an instruction from the CPU 171, a write address to the page memory unit 301, a read address from the page memory unit 301, and a read direction are controlled. Accordingly, the CPU 171 arranges a plurality of document images in the page memory unit 301 to perform layout, and controls a function of outputting to the printer unit, a function of cutting out and outputting only a part of the image, and an image rotation function.

Next, according to FIG. 6, the external I / F processing unit 4
Is described.

The external I / F processing unit 4 fetches the binary image data of the reader unit into the external I / F processing unit via the image memory unit 3 as described above, and The binary image data from the external I / F to the printer unit 2
To form an image. The external I / F processing unit 4 includes:
It has a core unit 406 and a facsimile unit 401, a hard disk 402 for storing communication image data of the facsimile unit, a computer interface unit 403 connected to the external computer 11, a formatter unit 404, and an image memory unit 405.

The facsimile unit 401 is connected to a public line via a modem (not shown), and receives facsimile communication data from the public line and transmits facsimile communication data to the public line. Facsimile unit 401
Then, the facsimile function, such as sending a fax at a designated time or sending image data by inquiring of a designated password from the other party, such as the hard disk 4
02, a fax image is stored and processed. Thereby, once from the reader unit 1 via the image memory unit 3,
After the image is transferred to the facsimile unit 401 and the facsimile hard disk 402, fax transmission can be performed without using the reader unit 1 and the image memory unit 3 for the facsimile function.

Computer interface unit 403
Is an interface unit for performing data communication with an external computer, and has a local area network (hereinafter, LAN), a serial I / F, an SCSII / F, a centro I / F for inputting data to a printer, and the like. Via this I / F, the statuses of the printer unit and the reader unit are notified to an external computer, and the image read by the reader unit 1 is transferred to the external computer according to instructions from the computer. Also, it receives print image data from an external computer. Since the print data notified from the external computer via the computer interface unit 403 is described in a dedicated printer code, the formatter unit 404 forms the image in the printer unit 2 via the image memory unit 3. Convert to raster image data.

The formatter unit 404 develops raster image data in the image memory unit 405. The image memory unit thus has the formatter unit 404
Is used as a memory for developing raster image data, or when the image of the reader unit is sent to an external computer via the computer interface unit 403 (image scanner function), the image data sent from the image memory unit 3 is used. It is also used in a case where the data is once expanded in the image memory unit, converted into a format of data to be sent to an external computer, and transmitted from the computer interface unit 403.

The core unit 406 includes a facsimile unit 401,
It controls and manages data transfer among the computer interface unit 403, the formatter unit 404, the image memory unit 405, and the image memory unit 3. Thereby, even if the external I / F processing unit 4 has a plurality of image output units or the image memory unit 3 has only one image transfer path,
Under the management of the core unit 406, exclusive control and priority control are performed, and image output is performed.

Next, the operation of the automatic document feeder (DF) 6 according to the present invention will be described with reference to FIGS. 7 (a) to 10 (m) which are schematic sectional views of the automatic document feeder 6.

First, each part of the DF 6 will be described with reference to FIG. Reference numeral 601 denotes a paper feed roller, which drops a document bundle 621 placed on a document tray 620 for placing a document bundle 621 made up of at least one sheet material, and rotates the document bundle 621 to rotate the document bundle. Feed the top document in the stack. Reference numeral 611 denotes a stopper, which protrudes as shown in FIG. 7A before the start of document feeding. The document bundle 621 is restricted by the stopper 611 so that it cannot advance downstream. The document fed by the paper feed roller 601 is separated into one sheet by the operation of the separation roller 602 and the separation belt 603. Separation is achieved by the well-known retard separation technique. A transport roller 604 transports the document separated by the separation roller 602 and the separation belt 603 to the registration roller 605. By hitting the document against the registration roller 605 and forming a loop, skew in the conveyance of the document is eliminated.

A reversing sheet flapper 613 is provided below the registration roller 605 to guide the document that has passed through the registration roller 605 to a sheet supply path 652 or a reverse entrance path 653, which is a conveyance path in the direction of the platen 201. Have been. Reference numeral 614 denotes a first reversing roller, and 615 denotes a second reversing roller, both of which rotate when the document is reversed. A reversing flapper 612 guides a document arriving from the direction of the second reversing roller 615 to the reversing path 650 or the re-feeding path 651. A belt driving roller 606 drives a feeding belt 607 for arranging a document on a platen. The feeding belt 607 is a platen 2
It is in contact with 01. Reference numeral 617 denotes a paper feed / discharge roller for feeding / discharging a document fed from the manual paper feed port 622 and feeding the document fed by the feed belt 607 to the document discharge port 62.
The paper is discharged to 3. Reference numeral 616 denotes a paper discharge flapper, which guides a document to a manual feed / discharge path 654 or a document discharge path 655. The paper discharge flapper 616 acts to prevent the document from being discharged toward the manual paper discharge port 622 when the document is discharged.
Reference numeral 619 denotes a manual feeding / discharging roller for feeding / discharging a manually fed document. Reference numeral 618 denotes a paper discharge roller for discharging a document.

In the lower part of the document tray 620, three sensors (608 to 610) are arranged. 610
Reference numeral denotes a document set detection sensor which is a transmission type optical sensor for detecting that the document bundle 621 is set. An original trailing edge detection sensor 608 is a reflection-type optical sensor for determining whether the original is a half-size original. 6 between the original set detection sensor 610 and the original trailing edge detection sensor
A final document detection sensor 09 is a reflection type optical sensor for determining whether the document being transported is the final document.

Reference numerals 624, 625, and 626 denote original size detection sensors for detecting the size of the original being conveyed. Three original size detection sensors are arranged in the width direction of the original. The width is detected in three stages, and the widths of the originals A and B or A4 and A5 are determined. Also, the original length is detected based on the passage time of the original. This makes it possible to detect individual document sizes even in a document bundle in which documents of different sizes are mixed. However, in this case,
It is assumed that the document bundle is placed with the rear side in the document width direction aligned.

Next, the operation of the automatic document feeder 6 when reading both sides of a document printed on both sides (double-sided document) will be described.

When the automatic document feeder 6 is instructed to start feeding a double-sided document, the stopper 611 is lowered, and the paper feed roller is further dropped on the upper surface of the document (FIG. 7B).

The original is separated from the uppermost surface of the original bundle 621 by the operation of the paper feed roller 601, the separation roller 602, the separation belt 603, and the transport roller 604, and is fed to the registration roller 605 (FIG. c)). At this time, the reversing paper feed flapper 613 is set in a direction for transporting the document to the reversing path.

When the registration rollers 605 rotate, the original is conveyed to the position shown in FIG. 8E via the path shown in FIG. 7D. From here, the driving directions of the first reversing roller 614 and the second reversing roller 615 are reversed, the document is fed onto the platen, and stops at the position shown in FIG.

When the reading of the original is completed, FIG.
As shown in FIG. 8, the original is turned over via a re-feed path 651, and as shown in FIG.
01.

When the reading of the document is completed, the document is fed rightward, and is discharged from the document discharge port 623 to the outside of the automatic document feeder 6. By repeating the above operation,
The two-sided document can be separated one by one from the top surface, read on both sides, and discharged with the top surface facing down (face down).

Next, the scanner 202 is fixed at a predetermined position, and the operation of the original reading method (flow reading) for reading the image by moving the original is described in the case where the original is only the small size and the case where the large size is included. I will explain separately. In the present embodiment, the small size is a size at which the document trailing end detection sensor 608 does not detect a document when the document bundle 621 is placed on the document tray 620, and the large size is a size at which the document bundle is placed on the document tray 620. When the document 621 is placed, the size of the document is detected by the document trailing edge detection sensor 608.

First, the flow-reading of a small-sized document alone will be described. The operation until the document reaches the registration rollers 605 is as described with reference to FIGS. 7A to 7C. In the case of the flow reading, as shown in FIG. 9I, the reversing sheet feeding flapper 613 guides the document onto the platen 201. The original is conveyed at a predetermined speed on point A in the figure,
The image of the original is scanned by the scanner 202 below the point A.
(FIG. 9 (j)). Point A is defined as the position where the trailing edge of the small size document has passed the registration roller 605. The original is conveyed to the right in the figure as it is, and is discharged out of the automatic document feeder 6 from the original discharge port 623 (FIG. 9 (k)).

Next, the flow reading of a document including a large size will be described. The operation until the document reaches the registration rollers 605 is as described with reference to FIGS. 7A to 7C. In the case of the flow reading, as shown in FIG.
Lead up one. The document is conveyed at a predetermined speed above point B in the figure, and the image of the document is read by the scanner 202 waiting below point B. Point B is defined as the position where the trailing edge of the large-sized document has passed the registration roller 605. The original is conveyed to the right in the figure as it is, and is discharged out of the automatic document feeder 6 from the original discharge port 623 (FIG. 10 (m)).

Finally, in the case of fixed document reading in which the scanner 202 is moved to read an image, the document is placed at a position where the rear end of the document matches the end of the platen 201 (the position shown in FIG. 8H).

Next, the document tray 6 of the automatic document feeder 6
FIG. 11 shows how the direction of the document bundle 621 set in the document tray 20 and the direction of the document bundle 621 conveyed and discharged to the document discharge port 622 correspond to each other. The original shown on the left side of FIG. 11 is the original bundle 6 set on the original tray 620.
21. Since the document is conveyed in order from the number 1 document on the uppermost surface of the document and is output with its front and back reversed, FIG.
As shown on the right side of FIG. 1, the uppermost document is turned upside down and discharged as the lowermost surface.

In the image forming apparatus having the above configuration, a control example in the case where the discharge tray of the sheet processing apparatus reaches the maximum stacking capacity in both the upper and lower stages will be described.

FIGS. 13 and 14 show the movement of the upper and lower trays when the upper and lower trays of the sheet processing apparatus reach the maximum stacking capacity. In FIG. 13, when sheets P are being stacked on the upper tray 292 (arrow 260) and both trays 292 and 293 reach the maximum stacking amount, FIG.
4, the sheet P is being stacked on the lower tray 293 (arrow 2).
60) shows a case where both trays 292 and 293 reach the maximum load capacity. The arrow 260 indicates the processing tray 270
To feed the sheet P.

FIG. 9 is a flowchart showing a control method in the case where both trays 292 and 293 reach the maximum load capacity, and are started when the printer 2 starts an image forming operation.

First, in S1, the image forming operation on the first sheet is started. Next, the process proceeds to S2, where the sheet on which image formation has been completed is discharged from the main body, and is stacked on the processing tray. Next, the process proceeds to S3, where it is determined whether the sheet stacked in S2 is the last sheet of the set. If it is not the last sheet, the process returns to S1, and the operations from S1 to S3 are repeated until the last sheet of the set is stacked on the processing tray. If it is the last sheet of the set in S3, S
Proceeding to 4, the sheet bundle of one copy stacked on the processing tray is discharged to the tray. Next, the process proceeds to S5, where it is determined whether or not all the images have been formed. If the processing has been completed, the processing ends.

If it is determined in S5 that the total number has not been counted, the process proceeds to S6, in which the upper and lower trays 292, 2
It is determined whether or not 93 has reached the maximum load capacity. If not reached, the process returns to S1, and the operations from S1 to S6 are continued. At this time, if the operation is continuous, the following operations of S1 and S2 may be performed before the determination of S6 ends.

In S6, if both trays 292 and 293 have reached the maximum stacking capacity, the process proceeds to S7, where the image forming operation of the image forming unit 210 (FIG. 2) on a new sheet is temporarily stopped, and The discharge of the sheet also stops.
Subsequently, the process proceeds to S8, where it is determined whether or not the discharged tray was the upper tray 292 when the image forming operation was temporarily interrupted.

If the sheet has been discharged to the upper tray 292 (FIG. 13 (a)), the process proceeds to S9, where the upper tray 292 is moved to the position of the processing tray 270 which is the start position at the time of resumption (FIG. 13 (b)). Then, the process proceeds to S10, and waits for the sheet to be removed by the user.

When the upper tray is removed (FIG. 13C), the upper tray is located at the start position, and
Since the sheet P can be discharged as it is, the process proceeds to S12,
The temporarily suspended image forming operation is resumed (FIG. 13
(D)). When the sheet P is removed from the lower tray 293 in S10 (FIG. 13E), the process proceeds to S11, the upper tray 292 is raised from the start position, the lower tray 293 is moved to the start position, and the process proceeds to S12. Then, the image forming operation is restarted (FIG. 13 (f)).

On the other hand, in S8, the tray discharged when the image forming operation is temporarily stopped is replaced with the lower tray 29.
If it is 3 (FIG. 14A), the process proceeds to S13, and the upper tray 292 is raised (FIG. 14B). this is,
This is to make it easier to take the sheets on the lower tray 293. Then, the process proceeds to S14, and waits for the sheet to be removed by the user.

The sheet P is removed from the upper tray 2
If it is 92 (FIG. 14C), the process proceeds to S16, where the lower tray 293 is lowered, the upper tray 292 is moved to the start position (FIG. 14D), and the process proceeds to S12. At this time,
Because it is difficult to take sheets from the lower tray 293,
After the sheet is removed from the lower tray 293, the upper tray 292 and the lower tray 293 may be lowered, or the lower tray 293 may be further lowered if possible.

If the sheet is removed from the lower tray 293 in S14 (FIG. 14 (e)), the process proceeds to S15, where the lower tray 293 is moved to the start position (FIG. 1).
4 (f)), the process proceeds to S12, and the temporarily stopped image forming operation is restarted. After the image forming operation is restarted in S12,
After that, the operations from S1 to S16 are continued until the processing for the set number of copies is completed.

As described above, by controlling the operation of the image forming unit 210 and the vertical movement of both trays 292 and 293, the number of sheets stacked on the upper and lower trays 292 and 293 reaches the upper limit. In such a case, it is possible to control so that the image forming operation is temporarily suspended, and after the sheets on the tray are removed, the image forming operation and the operation of stacking the sheets on the tray are restarted. When both trays 292 and 293 reach the upper limit, the upper tray 292 is raised, so that the user can easily remove the stacked sheets P and minimize the movement of the tray after resumption. be able to.

[0075]

As described above, according to the present invention,
When the stacking amount of the sheets stacked on the upper, lower, and both trays of the sheet processing apparatus reaches the maximum amount, the image forming operation of the image forming unit is temporarily suspended, and the upper or lower tray is stopped. After all the sheets are removed, the image forming operation of the image forming unit is restarted, so that the amount of paper loaded on the tray does not exceed the predetermined amount, and the job can be continued to the end. In addition, the upper tray is raised when the machine is temporarily stopped, so it is easier for the user to remove the stacked sheets, and it is possible to smoothly resume the image forming operation, thereby improving the usability of the user. can do.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a digital copying machine as an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a vertical sectional front view of the digital copying machine.

FIG. 3 is a control block diagram in the digital copying machine.

FIG. 4 is a block diagram of an image processing unit.

FIG. 5 is a detailed view of the image memory unit.

FIG. 6 is a configuration diagram of an external I / F processing unit.

7A is a vertical sectional front view of the automatic document feeder, and FIGS. 7B to 7D are operation diagrams.

FIG. 8 is an operation diagram of the automatic document feeder.

FIG. 9 is an operation diagram of the automatic document feeder.

FIG. 10 is an operation diagram of the automatic document feeder.

FIG. 11 is a diagram illustrating the direction of a document bundle discharged from a document discharge port.

FIG. 12 is a flowchart illustrating a control method when both trays of the sheet processing apparatus reach the maximum stacking amount.

FIG. 13 is a diagram illustrating a case where both trays reach the maximum stacking amount while being stacked on the upper tray of the sheet processing apparatus.

FIG. 14 is a diagram illustrating a case where both trays reach the maximum stacking amount while being stacked on the lower tray of the sheet processing apparatus.

[Explanation of symbols]

171 Control means of the image forming apparatus main body 200 Image processing apparatus main body 210 Image forming section (image forming means) 244 Discharge rollers (discharge means) 271 and 272 Sheet transport path (sheet transport means) 282 Control means 283a, 283b of sheet processing apparatus Tray drive unit (tray drive unit) 284a, 284b Load amount detection unit (load amount detection unit) 290 Sheet processing device 292 Upper tray 293 Lower tray 292, 293 Output tray

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 21/00 386 G03G 21/00 386 (72) Inventor Shunsaku Kondo 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Within Canon Inc. (72) Inventor Masahiro Serizawa 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term within Canon Inc. (Reference) 2H027 DB01 DB09 DC12 EC10 ED16 ED19 ED22 ED30 EE02 EE10 EH01 EH04 EK04 EK06 FA11 FA21 FA22 FA23 FA33 FA35 FA37 FD08 ZA07 ZA09 2H072 FB01 FB09 FB10 3F050 CA05 LA01 LB03 3F054 AA01 AC01 BA02 BF07 BF22 CA12 CA21 CA32 CA36 DA14

Claims (7)

[Claims] An upper tray, a lower tray for driving the upper tray and a lower tray for driving the upper tray and a lower tray, respectively; A sheet processing apparatus having upper and lower sheet conveying means for conveying, and upper and lower stacking amount detecting means for respectively detecting the stacking amount of sheets stacked on the upper and lower trays; and Image forming means for forming an image based on the image forming means, discharging means for discharging the sheet on which the image is formed by the image forming means to the sheet processing apparatus, and controlling the tray driving means, and to both the upper and lower trays That the sheet loading capacity of the
When the stacking amount detecting unit detects, the image forming operation by the image forming unit is temporarily stopped, and after all the sheets stacked on one of the upper and lower trays are removed, the remaining image forming operation is performed. And control means for controlling the upper drive means to raise the upper tray to a predetermined position when the control means temporarily suspends the image forming operation. An image forming apparatus comprising: 2. When the image forming operation of the image forming unit is temporarily interrupted during the stacking on the upper tray, the predetermined position at which the upper tray rises is a start position of the upper tray to which a sheet is conveyed. The image forming apparatus according to claim 1, wherein: 3. When the image forming operation is temporarily interrupted during loading on the lower tray, the predetermined position at which the upper tray rises is a position above a start position of the upper tray to which a sheet is conveyed. The image forming apparatus according to claim 1, wherein: 4. The control unit according to claim 1, wherein the sheets are removed from the upper tray after the trays reach the maximum load capacity while the upper tray is being loaded and the image forming operation of the image forming unit is temporarily stopped. 3. The image forming apparatus according to claim 1, wherein, in the case, the image forming operation of the image forming unit is restarted in a position where both trays are kept as they are, and the sheet is conveyed to the upper tray. 5. The control unit according to claim 1, wherein the sheets are removed from the lower tray after the trays reach the maximum load capacity while the upper tray is being loaded and the image forming operation of the image forming unit is temporarily stopped. In this case, the upper tray is raised from a start position, the lower tray is moved to the start position, the image forming operation of the image forming unit is restarted, and the sheet is conveyed to the lower tray. 3. The image forming apparatus according to 2. 6. The control unit according to claim 1, wherein the sheets are removed from the upper tray after the two trays reach the maximum loading capacity while the lower tray is being loaded and the image forming operation of the image forming unit is temporarily stopped. In this case, lower the lower tray,
The image forming apparatus according to claim 1, wherein the upper tray is moved to a start position, the image forming operation of the image forming unit is restarted, and the sheet is conveyed to the upper tray. 7. The control unit according to claim 1, wherein the sheets are removed from the lower tray after the trays reach the maximum load capacity while the lower tray is being loaded and the image forming operation of the image forming unit is temporarily stopped. 4. The image forming apparatus according to claim 1, wherein, in the case, the lower tray is moved to a start position, the image forming operation of the image forming unit is restarted, and a sheet is conveyed to the lower tray.