JP2899072B2 - Image forming device - Google Patents

Description

Description: 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 such as a copier and a laser printer, and more particularly to an apparatus having a double-sided function.

[Conventional technology]

2. Description of the Related Art Conventionally, a circulating document feeder is configured to feed a bundle of documents set on a document table one by one from the last page to an exposure position, and return the document to the same document table after the exposure. Less than
An image forming apparatus is known in which RDF is combined with an apparatus such as a copying machine.

In such an apparatus, when forming a plurality of copies of images using the RDF, a single-sided original is formed on both the front and back sides of a transfer sheet, and a single-sided original-two-sided copy mode is obtained to obtain one copy from two originals. When a plurality of copies of the image are output from the copy number setting means, a document is formed every other sheet while discriminating the number of documents during the first circulation in a cyclic sort mode in which the document is circulated a plurality of times. It is stored in the intermediate tray, and the image is formed while alternately repeating the paper feed cassette and the paper supply from the intermediate tray during the second to several circulations, and the image is fed while the document is fed from the intermediate tray every other sheet at the last circulation. Image formation has been performed in an image forming mode to be formed (hereinafter referred to as a skip mode).

However, if multiple feeds occur when forming multiple copies of an image using this method, it is necessary to specify the position where the double feed has occurred since this double feed is detected after the last copy is created. And could create many incomplete parts.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to form a single-sided original by RDF by forming images on both sides of a transfer sheet to obtain one copy from two originals. When performing the above-mentioned skip mode in the copy mode, by providing a recycle lever on the intermediate tray so that multiple feeds can be detected each time a document is circulated, parts other than the double feed generation unit can be completed as set. To provide an image forming apparatus capable of performing the following.

In order to achieve the above object, a single-sided original is image-formed on both front and back sides of a sheet of paper so that two originals are reduced to one
One-sided original duplex mode to obtain one copy is set,
When the number of copies is set by the copy number setting means, the document is circulated a plurality of times. At the first circulation, the number of the documents is discriminated and the sheet on which the document is formed every other sheet is determined. The sheets are stacked on the intermediate tray, and the image is formed while alternately repeating the sheet feeding cassette (or the sheet feeding deck) and the sheet feeding from the intermediate tray during the second circulation to the number of circulations. In an image forming apparatus having a skip mode for forming an image on sheet paper re-fed from the intermediate tray, the image forming apparatus is capable of appearing and retracting on a side portion of the intermediate tray, and the uppermost position of the intermediate tray at the end of one cycle of the document. A recycle lever that moves to a protruding position placed on the intermediate sheet and moves to a retracted position outside the intermediate tray when the uppermost sheet of the intermediate tray is re-fed; It provided a sensor for detecting the position of Ikurureba, wherein the sensor in one circulation of the document has to determine the double feed of the sheet paper by the position of the recycle lever detected.

Further, if the recycle lever is detected to be at the retreat position before one cycle of the document is completed, or if the recycle lever is detected to be at the retreat position before one cycle of the document is completed, an image is displayed. The method is characterized in that the forming operation is terminated.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 shows the internal configuration of an embodiment of the image forming apparatus of the present invention. In FIG. 2, reference numeral 100 denotes a main body having an image reading function and an image recording function, and 200 denotes a screen processing function for turning over a transfer sheet during double-sided recording and a multiplex recording function for performing multiple recordings on the same transfer sheet. Pedestal with 30
0 is a recirculating document feeder (hereinafter referred to as R
DF) and 400 are staple collating devices (hereinafter referred to as staple sorters). These devices 200 to 400 can be freely combined with the main body 100 and used.

A. Main unit (100) In the main unit 100, 101 is a platen glass on which an original is placed, 103 is an illumination lamp (exposure lamp) for illuminating the original, 1
05, 107 and 109 are scanning reflection mirrors (scanning mirrors) for changing the optical path of the reflected light of the original, 111 is a lens having focusing and zooming functions, and 113 is a fourth reflection mirror (scanning) for changing the optical path. Mirror). Reference numeral 115 denotes an optical system motor for driving the optical system, and 117, 119, and 121 denote sensors.

131 is a photosensitive drum, 133 is a main motor for driving the photosensitive drum 131, 135 is a high-pressure unit, 137 is a blank exposure unit, 139 is a developing device, 141 is a transfer charger, 147 is a separation charger, and 145 is a cleaning device. is there.

151 is an upper cassette, 153 is a lower cassette, 171 is a manual paper feed port, 155 and 157 are paper feed rollers, and 159 is a registration roller. Reference numeral 161 denotes a transport belt for transporting the transfer paper on which the image has been recorded to the fixing side; 163, a fixing device for fixing the transported transfer paper by thermal fixing; 167, a sensor used for double-sided recording.

The surface of the photosensitive drum 131 is made of a photoconductor and a seamless photosensitive member using a conductor. The drum 131 is rotatably supported by a shaft, and operates in response to pressing of a copy start key described later. The rotation is started by the motor 133 in the direction of the arrow in FIG. Next, when the predetermined rotation control and potential control processing (preprocessing) of the drum 131 is completed, the original placed on the original platen glass 101 is illuminated by the illumination lamp 103 integrated with the first scanning mirror 105, The reflected light of the original is supplied to a first scanning mirror 105, a second scanning mirror 107, a third scanning mirror 109, a lens 111, and a fourth scanning mirror 11
The image is formed on the drum 131 via 3.

The drum 131 is corona-charged by the high-pressure unit 135. Thereafter, the image (original image) irradiated by the illumination lamp 103 is subjected to slit exposure, and an electrostatic latent image is formed on the drum 131 by a known Carlson process.

Next, the electrostatic latent image on the photosensitive drum 131 is developed by the developing roller 140 of the developing device 139 and visualized as a toner image, and the toner image is transferred onto transfer paper by the transfer charger 141 as described later. .

That is, the upper cassette 151 or the lower cassette 153
The transfer paper therein or the transfer paper set in the manual paper feed port 171 is sent into the main body by the paper feed rollers 155 or 157, and the leading end of the latent image and the leading end of the transfer paper are matched. After that, the transfer paper passes between the transfer charger 141 and the drum 131, and is discharged out of the main body 100.

After the transfer, the drum 131 continues to rotate, and the surface thereof is cleaned by a cleaning device 145 including a cleaning roller and an elastic blade.

The pedestal 200 has a paper feed deck 201 which can be separated from the main body 100 and can store 2000 sheets of transfer paper, and an intermediate tray 203 for double-sided copying. The lifter 205 of the sheet feeding deck 201 capable of storing 2,000 sheets rises according to the amount of the transfer sheet so that the transfer sheet always contacts the sheet feeding roller 207.

Also, reference numeral 211 denotes a paper discharge flapper for switching a path between a double-sided recording side or multiple recording side or a reverse discharge path and a discharge side path, 212 a reverse discharge switchback roller, and 213 a double-sided recording side or multiple recording side and a reverse discharge path. This is a reversing sheet discharge flapper that switches the path to the path of (1), and guides the transfer sheet to the switchback roller 214 by rotating to the right. 215
Denotes a transfer path of the transfer belt, and 217 denotes an intermediate tray weight for holding the transfer sheet. Paper discharge flapper 211, and conveyance path 214,
The transfer paper passing through 215 is turned over and stored in the intermediate tray 203 for double-sided copying. Reference numeral 219 denotes a multiplex flapper for switching the path between double-sided recording and multiplex recording. The flapper 219 is disposed between the conveyance paths 214 and 215, and guides the transfer paper to the multiplex recording conveyance path 211 by rotating upward. Reference numeral 223 denotes a multiple discharge sensor for detecting the end of the transfer paper passing through the multiple flapper 219. A paper feed roller 225 feeds the transfer paper to the drum 131 through a path 227. Reference numeral 229 denotes a discharge roller for discharging the transfer paper outside the apparatus.

At the time of double-sided recording (double-sided copying) or multiple recording (multiplexed copying), first raise the discharge flapper 211 of the main body 100 to
Transfer the copied transfer paper to the transport paths 214 and 215 of the VEDESTAL 200.
Is loaded on the intermediate tray 203 via the. At this time, the multiplex flapper 219 is lowered during double-side recording, and the multiplex flapper 219 is raised during multiplex recording. This intermediate tray 203
Can load, for example, up to 99 transfer sheets.
The transfer paper loaded on the intermediate tray 203 is the intermediate tray weight 2
Pressed by 17. In the skip mode described above, the recycle lever shown in FIGS.
218 is placed on the uppermost transfer sheet as a partition for the transfer sheet on the intermediate tray at the end of one cycle of the original.

At the time of the next backside recording or multiplex recording, the transfer paper stored in the intermediate tray 203 is transferred one by one from the bottom to the resist of the main body 100 via the path 227 by the action of the paper feed roller 225 and the weight 217. It is guided to the roller 159.

Also, at the time of reverse discharge, the reverse discharge flapper 213 is rotated to the right, the transfer paper is guided to the switchback roller 212, and then after the transfer paper sufficiently reaches the switchback roller 212, the switchback roller 212 is reversely rotated. The transfer paper is discharged by a discharge roller 229 to a discharge unit (staple sorter) outside the apparatus.

FIGS. 1A and 1B show the recycle lever 21 described above.
8 shows a lever position detecting device for judging double feeding of transfer paper, and a lever position detecting device 41
8, a recycle lever 218 that can freely move in and out of one side, a recycle motor 42 that rotationally drives the recycle lever 218,
It comprises a flag 46 that rotates integrally with the recycle lever 218 and has a notch, and a recycle sensor 47 that detects the position of the recycle lever 218 by detecting the flag 46.

45 is fixed to the drive shaft of the recycle motor 42,
This is a lever rotation pin that rotates the recycling lever 218 clockwise in accordance with the rotation of 42.

When one cycle of the document is completed, the recycle lever 218 is rotated to a solid line position (projection position) by the motor 42 and is placed on the uppermost transfer sheet S stacked on the intermediate tray 203. When the uppermost transfer sheet on the intermediate tray 203 is re-fed, it rotates to the chain line position (retreat position) by its own weight and retreats to the outside of the intermediate tray 203.

The recycle sensor 47 detects the flag 46 when the recycle lever 218 is placed at the protruding position, and turns on when the recycle lever 218 is placed at the retracted position.
becomes f.

As described later, the recycle sensor during one cycle of the original
The presence or absence of double feeding of the transfer paper can be determined based on the output state of 47.

B. RDF (Circulating Document Feeder) (300) In the RDF 300, reference numeral 301 denotes a stacking tray on which a document bundle 302 is set. First, in the case of a single-sided original, the originals are separated one by one from the lowermost portion of the original bundle 302 by the half-moon roller 304 and the separation roller 303, and the separated original is passed by the transport roller 305 and the full-surface belt 306 to the exposure position of the platen glass 101. IIII, and the copying operation is started. After copying is completed, the original on platen glass 101 is
The sheet is sent to the paths V and VI by the large conveying rollers 307 through II and IV, and is returned to the uppermost surface of the original bundle 302 by the sheet discharging rollers 308 again.

Reference numeral 309 denotes a recycle lever for detecting one cycle of the document. The recycle lever 309 is placed on the top of the document bundle at the time of starting document feeding, and the documents are sequentially fed, and the rear end of the final document passes through the recycle lever 309. At this time, the document is dropped on the stacking tray 301 by its own weight, thereby detecting one cycle of the document.

Next, in the case of a two-sided original, as described above, the original is once guided from the paths I and II to the path III, and after copying is completed, the leading end of the original is guided to the path by switching the rotatable switching flapper 310. The document is stopped on the platen glass 101 by the entire belt 306 through the path II. That is, the rotation of the large transfer roller 307 causes the path I
The document is reversed in the route from II to IV to II.

In addition, the document bundle 302 is passed one by one through paths I to II to III to IV to V.
By transporting the document until it is detected by the recycle lever 309 through .about.VI, the number of documents can also be counted.

C. Staple sorter (collapsing device with staple) (40
0) The staple sorter 400 has a fixed non-sort tray 411 of 20 bins and performs collation.

In the case of the sort mode, the copied sheets are sequentially discharged from the paper discharge rollers 229 of the main body, enter the transport rollers 401 of the sorter 400, and are discharged from the discharge rollers 405 to the respective bins of the tray 412 through the transport path 403. Each time, bins are moved up and down by a bin shift motor (not shown) to perform collation. Also, when staple mode is selected,
When a staple signal is input from the main body 100, the staple device 420 is moved while being moved by I bins by the bin shift motor.
Staples the sheets in each bin.

D. Control Device (800) FIG. 3 shows a configuration example of the control device 800 of the embodiment shown in FIG. In FIG. 3, reference numeral 801 denotes a central processing unit (CPU) for performing arithmetic control for executing the present invention, and uses, for example, a 16-bit microcomputer. Reference numeral 803 denotes a read-only memory (ROM) in which a control procedure (control program) according to the present invention is stored in advance.
It controls each component device stored in the OM803. Reference numeral 805 denotes a random access memory (RAM) which is a main storage device used for storing input data, a work storage area, and the like.

Reference numeral 807 denotes an output signal transfer interface (I / O) for outputting a control signal of the CPU 801 to a load such as the main motor 133;
Reference numeral 811 denotes an input signal transfer interface for inputting an input signal from the image sensor 121 or the like and sending the input signal to the CPU 801; These interfaces 807, 809, 811 use, for example, an input / output circuit port 8255.

The display group 700 uses, for example, LEDs (light emitting diodes) and LCDs (liquid crystal displays). The key group 600 is each key, and is configured so that the CPU (801) can determine which key is pressed by a known key matrix.

In the above-described skip mode, when the number of documents is N, the document is read every other sheet, such as N, N-2, N-4,. An image is formed and the transfer paper is transferred to the intermediate tray 203.
Transport to After this operation is completed, as shown in FIG.
The recycle motor is started, and the recycle lever 309 rotates to press the uppermost portion of the document bundle S. At the same time, as shown in FIGS. 1A and 1B, the recycle lever 218 is also rotated by the recycle motor 42 and presses the uppermost portion of the transfer paper. In this first cycle, it is determined whether the document is an odd number or an even number. From the second cycle to the copy cycle, if the original is an even number,
For the originals of N-2, N-4,..., Transfer paper is fed from a cassette, an image is formed again, and is conveyed to the intermediate tray 203, during which N-1, N-3, N The originals of -5... Are re-fed from the intermediate tray 203 to form an image on the back surface, and are discharged to a discharge unit. After this is completed, the recycle lever 218 falls to the chain line position by its own weight if it is not multi-fed.
The recycle sensor 47 can detect the final position on the intermediate tray of the transfer paper corresponding to one cycle of the document bundle S by detecting the flag 46 that is displaced with the movement of the recycle lever 218.

In the case of an odd number, the operation of the recycle lever is the same, but after the second circulation, first, the N
Re-feed the transfer paper on which the original document was formed, but the blank LE
No image formation is performed by the entire-surface erasing means by D control.
When the number of documents is an odd number, reversal discharge described below is performed. In the final circulation, the intermediate tray 20 from the second circulation to the circulation
Image formation is performed in the same manner as in the case of re-feeding from 3.

The motor 42 of the recycle lever 218 is activated by detecting a signal indicating the end of one cycle of the original, and the recycle lever 218 is operated.
Is placed on the uppermost transfer paper on the intermediate tray 203.
The end of one cycle of the document is detected by the position of the document recycle lever 309.

Embodiment 1 Next, an example of a recycle lever operation when the present invention is applied to a copying machine will be described with reference to FIG.

When the skip mode is used in the one-sided original-double-sided copy mode using the RDF, the following operation is performed.

First, as described above, the original conveyed by RDF
The transfer sheet is conveyed to the intermediate tray 203 while reading every other sheet and transferring it to the transfer sheet (step 5-1).

When the last transfer sheet has been conveyed to the intermediate tray 203, the recycle lever 218 is turned on (step 5-2). Next, the document is circulated for a second time, and as described above, the transfer paper is alternately fed from both the cassette and the intermediate tray, the transfer paper fed from the cassette is transferred to the front side, and re-fed from the intermediate tray. The image is transferred to the back side of the paper to be transferred (step 5-3), and it is determined whether the document has completed one round (step 5-4).

If the recycle sensor 47 is turned on (step 5-5) before one round of the original document, it is determined that the transfer paper has been multi-fed when re-feeding from the intermediate tray 203 (step 5-8), and the copying is in progress. After the transfer paper is discharged, the copying operation is terminated with a warning (step 5-10) such as an alarm display or an alarm sound. Also, after one round of the manuscript, the recycle sensor 47
When it is off, it is determined that multiple feeds have been made when feeding the cassette, and the transfer paper is re-fed from the intermediate tray 203 until the recycle sensor 47 turns on, and the image is not transferred to this re-fed transfer paper. The copying operation is terminated (step 5-7). At the end of the copying operation, a warning such as an alarm display or an alarm sound is issued (step 5-10).

The above operation is performed until the set number of copies is completed, unless double feed occurs. (Step 5-9).

Another Embodiment 2 Next, an example of the operation of the recycle lever when the present invention is applied to a copying machine will be described with reference to FIG.

When the skip mode is used in the one-sided original-double-sided copy mode using the RDF, the following operation is performed.

First, as described above, the transfer paper is conveyed to the intermediate tray 203 while transferring every other document by the RDF (step 6-1).

When the last transfer sheet has been conveyed to the intermediate tray 203, the recycle lever 218 is turned on (step 6-2). Next, while alternately feeding paper from the cassette and the intermediate tray (step 6-3) as described above, it is determined whether the document has completed one cycle (step 6-4).

If the recycle sensor 47 is turned on (step 6-5) before one round of the document, it is determined that the multi-feed has been performed when re-feeding the sheet from the intermediate tray 203, and after the transfer sheet currently being copied is discharged, This circulation copying operation is completed (step 6-).
8) Open the sorter by shifting it by one bin (step 6-1)
0), the next cyclic copying operation is performed. Also, when the recycle sensor 47 is off after one round of the document, it is determined that multi-feeding has occurred when feeding from the cassette, and paper is re-fed from the intermediate tray until the recycle sensor 47 is turned on. Is discharged without transferring (step 6-7), the sorter is shifted by one bin, and the next circulation copy operation is performed.

The above operation is performed until the set number of copies is completed (step 6).
-9). After completion of the set number of copies, if a double feed has occurred in the middle (step 6-12), a warning such as a double feed occurrence alarm or an alarm sound (step 6-13) is issued and the double feed occurs again. The position of the part is indicated by shifting the sorter by one bin.

Third Embodiment Next, an example of a double-sided sequence operation when the present invention is applied to a copying apparatus will be described with reference to FIG.

When the skip mode is used in the one-sided original-double-sided copy mode using the RDF, the following operation is performed.

First, as described above, the document is transferred to the intermediate tray 203 while transferring every other document by RDF (Step 7-).
1).

When the last transfer sheet has been conveyed to the intermediate tray 203, the recycle lever 218 is turned on (step 7-2). Next, while alternately feeding paper from the cassette and the intermediate tray as described above (step 7-3), it is determined whether the document has completed one cycle (step 7-4).

If the recycle sensor 47 is turned on (step 7-5) before one cycle of the document, it is determined that the multi-feed has been performed when re-feeding the sheet from the intermediate tray 203, and after the transfer sheet currently being copied is discharged, This circulation copying operation is completed (step 7-).
8) Store the discharged sorter position (Step 7-10),
The next cyclic copying operation is performed. Also, when the recycle sensor 47 is off after one round of the document, it is determined that multi-feeding has been performed when feeding from the cassette, and the sheet is re-fed from the intermediate tray until the recycle sensor 47 is turned on. The image is discharged without being transferred (step 7-7), the position of the discharged sorter is stored (step 7-10), and the next circulation copying operation is performed.

The above operation is performed until the designated number of copies is completed (step 7).
-9). Here, the designated number of copies is (set number of copies) + (multiple feed count). That is, the copying operation is completed when the set number of copies is completed normally. After completion, if a double feed has occurred in the middle (step 7-12), the bin number of the sorter where the double feed has occurred is displayed along with a warning (step 7-13) such as a double feed alarm display or an alarm sound. Display (Step 7-14)
I will do it.

〔The invention's effect〕

The single-sided original conveyed by RDF is image-formed on both sides of the sheet paper, and a single copy is obtained from two originals. By providing the recycle lever, it is possible to determine the double feed of the sheet paper for each circulation of the document.

[Brief description of the drawings]

Fig. 1 shows the configuration of the intermediate tray and the recycling lever.
(A) is a plan view and (b) is a front view. FIG. 2 is a cross-sectional view showing the internal configuration of the entire embodiment, FIG. 3 is a block diagram showing the circuit configuration of a control device of the embodiment, FIG. 4 is an operation sequence of the first embodiment, and FIG. Sequence FIG. 6 shows an operation sequence of the third embodiment. 203: Intermediate tray 218: Recycle lever 300: Recirculating document feeder

Continuing on the front page (72) Inventor Satoshi Kuroyanagi 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tokuharu Kaneko 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) reference Patent flat 2-100061 (JP, a) JP Akira 58-150972 (JP, a) JP Akira 53-99942 (JP, a) (58 ) investigated the field (Int.Cl. ⁶ , DB name) B65H 83/00-85/00 G03G 15/00

Claims (4)

(57) [Claims] A circulating automatic document feeder for automatically feeding a plurality of documents placed on a document table to an image reading position, and discharging the documents to return to the document table after reading; Image reading means for reading an image of a document at a reading position, image forming means for forming an image read by the image reading means on a sheet of paper, mode input means for inputting an image forming mode, and setting the number of image forming copies A number setting unit; an intermediate tray for stacking sheet sheets after image formation on one side; and a re-feeding unit for re-feeding the sheet sheets stacked on the intermediate tray one by one to the image forming unit. A single-sided original-double-sided copy mode in which a single-sided original is image-formed on each of the front and back sides of the sheet paper by the mode input means to obtain one copy from two originals; When performing formation, it is circulated several times an original, 1
At the time of the second circulation, the sheets formed by image forming every other document are stacked on the intermediate tray while discriminating the number of the originals. A skip mode in which an image is formed on a sheet while alternately repeating the sheet feeding from the intermediate tray, and every other document image is printed on the sheet re-fed from the intermediate tray during the last circulation. An image forming apparatus having an intermediate tray that is movable to the side of the intermediate tray and moves to a projecting position placed on the uppermost sheet of the intermediate tray at the end of one cycle of the document; A recycle lever that moves to a retracted position outside the intermediate tray when the uppermost sheet of paper is re-fed, and a sensor that detects the position of the recycle lever. An image forming apparatus characterized by being adapted to determine the double feed of the sheet paper by the position of the detected said recycle lever. 2. The image forming operation according to claim 1, wherein if the recycle lever is detected to be at the retracted position before the circulation of the document is completed, the image forming operation is terminated. An image forming apparatus according to claim 1. 3. The image forming apparatus according to claim 1, wherein when one cycle of the original document is completed, when it is detected that the recycle lever is at the projecting position, the image forming operation is ended. The image forming apparatus as described in the above. 4. When the recycle lever is detected to be in the protruding position when one cycle of the original document is completed, the sheet stacked on the intermediate tray is discharged to a discharge section. The image forming apparatus according to claim 3, wherein: