JPH0486759A - Image recorder - Google Patents

Abstract

PURPOSE:To prevent a failure in copying by ejecting a transfer sheet whose one-side is finished to be copied and carrying out both-side copying from an original fed after a double sheet, when the double sheet is detected and the number of the originals in a group just before the double sheet is odd, at the time of a both-side copying mode. CONSTITUTION:An IPU 1 (image processor) 201 counts the number of the picture elements of the black part of the original. When the number of the picture elements is a limiting value set in advance or below, the IPU 1 201 judges that the original is blank. When the blank original is detected, it is judged that the blank original is the double sheet. The number of the originals having image recording up to this time, is odd, the transfer sheet is ejected without carrying out the image recording to the back side. Even if the number of the originals of one group is odd or even, both side copying is carried out from the next original again. Thus, when plural groups of the originals are set to carry out the both-side copying, the final original of a group of the originals having the odd number and the first original of the next group of the originals are prevented from being copied on the front and back sides of transfer sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a digital copying device equipped with an automatic document feeder and a double-sided copying device.

Conventional technology Multiple single-sided originals are stacked on an automatic document feeder (ADF), and the originals are continuously fed to the reading unit to print two successive originals on both the front and back sides of a single sheet of transfer paper. When copying in one-sided/double-sided copy mode, if the originals of multiple original groups are fed consecutively at random and double-sided copying is performed, if the first original group consists of an odd number of originals, the last original is copied onto the front side of the transfer paper, and the first original of the next group of originals is copied onto the back of the transfer paper on which the last original of the previous group of originals has been copied. Therefore, after completing a series of copies, if you try to separate the double-sided copies by document group, it will be impossible to separate them because the originals of another document group are copied on the front and back sides of one copy. This will cause a problem.

Conventionally, when copying multiple groups of originals using the ADF in single-sided/duplex mode, only one group of originals can be copied using the ADF.
When copying is completed for one group of originals, you can set the next group of originals, or you can count and input the number of sheets in each group of originals in advance, and then count the number of fed originals. A method has been used in which the boundaries between groups of documents are detected, and if the group has an odd number of sheets, the last document in the group is controlled so that only one side is copied.

However, in the former method, the operator must wait until the copying of one group of documents is completed before setting the next group of documents in the ADF, which reduces the benefit of using the ADF by half.

In the latter method, the operator does not have to wait on the machine side to set the originals, but the operator must first count the number of originals in each group of originals, and the input method is also complicated.

When dividing a stack of originals placed on the ADF into multiple groups, there is a method of inserting interleaving paper at the boundary between the original groups and detecting this when the paper is fed to determine that the original group has changed. This is disclosed in Japanese Patent Application Laid-Open No. 1-177566, but the purpose is to change the copy mode itself before and after the interleaf sheet, so that even if the document group changes, the copy is made in the same copy mode, and the previous document is copied at the boundary. There is no disclosure of any method for preventing the pages of a group and the first page of the next document group from being copied on the front and back sides of a single copy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the conventional digital image recording device equipped with an ADF and a double-sided copying device when double-sided copying is performed by continuously feeding a plurality of groups of originals. , when double-sided copying is performed by loading multiple document groups into the ADF at the same time and feeding them continuously, the last document in the document group consisting of an odd number of sheets and the first document in the next document group. An object of the present invention is to provide an image recording device that can prevent images from being copied on the front and back sides of a sheet of transfer paper.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides an automatic document feeder that continuously feeds originals one by one from a stack of originals to an original reading section, and a transfer sheet that has been recorded on one side once. In a digital image recording device equipped with a double-sided copying device having a double-sided tray that accepts and refeeds paper for recording on the back side, the automatic document feeder feeds the document from a document stack consisting of a plurality of document groups. In this case, the apparatus includes a slip sheet detection means for detecting that a slip sheet sandwiched between the boundaries of the document group has been fed, and a means for counting the number of fed document sheets. When a slip sheet is detected by the counting means, if the number of sheets of the document group immediately before it is an odd number according to the count value by the counting means, at that point, copy the back side of the transfer paper that has been copied on one side on the duplex tray of the duplex copying device. control so that the originals fed after the interleaving sheet are processed in double-sided copy mode regardless of whether the number of sheets in the group of originals immediately before the interleaving sheet is an odd number or an even number. It is characterized by

Function: Since the image recording device of the present invention is configured as described above, a plurality of groups of originals are set in the ADF with interleaf sheets sandwiched between them, and the originals are automatically fed and double-sided. When copying is performed in the copy mode, when a slip sheet is fed, it is detected by the slip sheet detection means, and it is determined that it has reached the boundary between the document groups.

The number of originals fed is counted by a counter, and the number of sheets from the start of original feeding at the above-mentioned interleaf sheet detection ratio or from the start of the first original after the previous interleaf sheet detection is known. If the number of originals is an even number, these originals are copied on both sides of the transfer paper, and no transfer paper remains on the duplex tray. On the other hand, if the number of originals in the original group immediately before the detection of a slip sheet is an odd number, the number of sheets of transfer paper on which one-sided copies have been made for the last original in the original group on the duplex tray is equivalent to the number of copies. It is in a state where it is only loaded. According to the present invention, this transfer paper is ejected from the machine without performing back-side copying, and double-sided copying is performed again from the next original regardless of whether the number of sheets in the group of originals is odd or even. It is avoided that manuscripts from another manuscript group are copied on both sides of the transfer paper, and
It also prevents the operator's effort from increasing.

Embodiments Below, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a diagram showing a schematic overall configuration of a copying system including a digital copying machine to which the present invention is applied.

The digital copying machine 10 is placed on a table 11, and an automatic document feeder (ADF) 130 is installed on the top of the table 11, covering a contact glass 119 for placing an original to be read. , a large-capacity paper tray (LCT) 140 is attached to the lower part of the paper feed section, a duplex unit 134 is attached to the paper ejection side of the copying machine main body 10, and a sorter 18 is attached to the side of the duplex unit 134. one replication system is configured.

The copying machine main body 10 has a reading section (scanner) 12 in order from the top.
, a writing section 13 , and an image forming section 14 .

The reading unit 12 includes an exposure lamp 113 provided below the conductive glass 119 and first to third mirrors 121, 1
22, 123, imaging lens 111, image reading plate 110
The original placed with the image surface facing down on the contact glass 119 is slit-illuminated by the exposure lamp 113, and the reflected light is reflected by the mirrors 121, 122,
123, image reading plate 110 via the imaging lens 111
image and perform reading scanning by moving the exposure lamp 113, the first scanning body carrying the first mirror 121, and the second scanning body carrying the second and third mirrors 122 and 123 at a predetermined speed. The original image is read by the CCD on the image reading plate 110, converted into an electrical signal, and then processed by IPU (Image Processing) which will be described later.
The image is processed in the unit (image processing device) and sent to the writing unit 13.

The writing unit 13 is a laser diode, a polycon motor]
Polygon mirror 124, f-θ rotating at a constant speed by 09
In an optical system consisting of lenses and the like, the laser light emitted from the laser diode is modulated by an image information signal as an electrical signal that has been image-processed by the above-mentioned PU, and passes through a polygon mirror 124, an fθ lens, etc. to the image forming unit 14. An image is written on the photosensitive drum 101.

The configuration of the image forming unit 14 is the same as that of an image forming apparatus using a known electrophotographic process, and the photosensitive drum 101
Chargers 112 are arranged around the
, the image writing position, the developing unit 117, the transfer charger 1021, the separation charger 103, the separation claw 127,
A cleaning unit 104 is provided, and the toner image formed on the photoreceptor drum 101 by a known electrophotographic process is sent out by a paper feed roller 116 from a paper feed force 115 or a large capacity paper feed tray 140. , and is transferred under the action of the transfer charger 102 onto a transfer paper 125 that is fed to the transfer section with timing by the registration rollers 126. Transfer paper after transfer is separated into charger 1
03 and separating claws 127 to separate the photoconductor 1 to the ram 101.

On the conveyance path of the separated transfer paper, there is a transfer heald 128 that attracts the transfer paper to the surface and conveys it using the conveyance fan 105.
, a fixing unit 107 and a conveyance roller 129 are arranged in sequence, and the transfer paper 125 separated from the photoreceptor drum 101 is fixed by the fixing unit 107 by a transfer heald 128 and then discharged to the outside of the machine by the conveyance roller 129. The ejected transfer paper is ejected to the sorter 118 or the duplex tray 133 in the duplex unit 134 depending on the copy mode by a switching claw 131 provided in the paper receiving section of the duplex unit 134.

In the case of the double-sided copy mode, it is necessary to turn over the transfer paper 125 on which an image has been recorded on one side, and transport it to the image forming section 14 again. Therefore.

The transfer paper 125 discharged by the conveyance roller 129 is transferred to the duplex tray 13 of the duplex unit 134 by the switching claw 131.
3, it will be released and stocked.

The double-sided tray 133 includes a jogger fence 135 for horizontally aligning the ejected transfer paper, and a vertically movable latch for feeding the leading edge (original rear end) of the ejected transfer paper until it collides with a stop plate 137. A roller 136 is provided, and the ejected transfer paper is stacked with its leading edge and left and right sides aligned. When refeeding paper from the double-sided tray 133, the stop plate 137 is moved downward by a solenoid (not shown), and the transfer paper is sent out with the original rear end first by a refeed roller 138.
The image is sent through the circulation path 132 in the table 11 to the registration roller 126 of the image forming section 14 by the conveyance roller 139, and is fed to the transfer section at a predetermined timing, where the image is transferred to the back side and fixed, and then transferred to the sorter 118. Ejected to the tray.

Next, the flow of the image signal will be explained based on the image signal flow diagram shown in FIG.

As described above, the original on the contact glass 119 is exposed by the exposure lamp 113, and the reflected light passes through the first to third mirrors 121, 122, 123, and is focused on the CCD 110a in the image reading plate 110 by the imaging lens 111. imaged. Here, CCD1]Oa converts the shading of the original into an electrical signal, and in this example, it is a 5000 pixel CCD.
It has a resolution of 400 dpi. The image reading board 110 has a built-in A/D converter, and the analog output from the CCD 110a is 6b11 (6
It is output as a digital signal with 4 gradations).

The image data output from the image reading board is IPUl (
(image processing device) 201. IPLil (2
01) has a function of not only performing shading correction and MTF correction of image data but also binarizing image data and counting the number of pixels in a black portion. The data processed by IPol (201) is temporarily stored in the image memory (RAM) 20.
2. The data on the image memory is stored in IPU2 (
203), and performs image processing such as scaling processing, black and white inversion processing, and halftone processing as necessary. Furthermore, I
The PUI (201) and IPU2 (203) are configured to be connected to a main control board 205 that controls the entire image processing apparatus and exchange data.
What kind of image processing the IPU2 (2Ql) and IPU2 (203) perform is determined by various commands sent from the main control board 205.

In addition, IPU1 is capable of sending the number of pixels in the black part of the image data mentioned above to the main control board 205.
The image-processed data in step 2 is sent to the LD control board 204, and the image is written on the photosensitive drum 101 by controlling the amount of light emitted from the LD (laser diode) according to the data. Note that the laser beam from the LD is configured to be scanned onto the photosensitive drum 101 by a polygon mirror 124 rotating at high speed, and one main scan is performed on one surface of the polygon mirror 124. The mirror surface of the polygon mirror 124 is processed with ultra-precision processing to prevent the writing position of the laser beam from shifting in the main scanning and sub-scanning directions and to increase the reflection efficiency.

FIG. 3 shows an operation panel 301, which is provided with various switch keys for operating the image recording apparatus. first,
Print key 302, numeric keypad 303, C/S on the right side
(Clear/stop) key 304, interrupt key 3
05 is provided, and to the left of it are an automatic paper selection key 306 for automatically selecting the paper feed cassette 115 and LCT 140 according to the document size, a paper selection key 307 for selecting the paper feed cassette, and a paper selection key 307 for selecting the paper feed cassette. A paper specifying magnification key 308, an equal magnification key 309, an enlargement key 310, and a reduction key 3]1 are provided to automatically enlarge or reduce the size according to the transfer paper size of the paper cassette. Furthermore, on the left are a slip sheet detection mode key 312 for determining that a blank document is a slip sheet according to the present invention, a page continuous copy mode key 313, a double-sided copy mode key 314, and a sort/stack mode key 315.
A display section 316 for displaying various messages is provided at the upper center of the screen.

Next, the operation of the ADF (automatic document feeder) 130 will be explained using the ADF mechanism schematic diagram shown in FIG. When a document is placed on a document table 401 on the ADF, a document center detection 402 detects that the document is set. When the print key 302 of the operation panel 301 is pressed, the pinch roller 403 and the calling roller 404 come into contact with each other, and then a transport motor (not shown) is turned on, thereby rotating the calling roller and feeding the original. When a plurality of originals are fed, only the originals that are in contact with the separation belt 405 and the separation roller 406 are fed. The document that has been fed and passed through the separation roller 406 passes through a registration and document width detection 407, and then is transferred to the conveyor belt 4.
08 onto the contact glass 119. At this time, the paper size of the original is detected by length detection 409 and registration and original width detection 407. On the other hand, when the document sent onto the contact glass 119 hits the length detection 409, the conveyance motor is stopped and the document is stopped at the exposure position. After exposure, the original is ejected by rotating the transport motor and the ejecting motor (not shown) and lowering the stop claw, and the next original is fed again. When the back side of a double-sided original is exposed, after the front side has been exposed, it is conveyed again around the two inversion ports 410 (at this time, the inversion switching claw 411 is raised) onto the contact glass. The originals that have been exposed and discharged from the machine are stored in the original receiver 413.

Based on Flowchart 1, we will explain in detail the operation when using the image recording device configured in this way to stack a plurality of document groups, transfer them to the ADF, and perform continuous double-sided copying in the single-sided to double-sided copy mode. explain.

FIG. 5 is a control flowchart of the interleaf sheet detection and double-sided copy mode of a single-sided original to which the present invention is applied.

Note that the slip sheet detection mode is set, for example, by pressing the slip sheet detection mode key 312 on the operation panel 301.
For single-sided original or double-sided copy mode, press the double-sided copy mode key 31.
Set by pressing 4. FIG. 5 shows the flow after this. First, print key 30
When 2 is pressed (step 1 (hereinafter and in the figures, step is abbreviated as S)), a document is fed from the ADF 13'O (S2). Next, it is detected whether the fed document is blank (S3). Blank page detection is performed by exposing and scanning the document using a scanner, counting the number of pixels in dotted portions of the document, and determining that the document is blank if the number of pixels is less than a predetermined limit value. When it is determined by the blank page detection process that the document is not a blank page and is determined to be a normal document, the above-described image recording operation is performed (S4). Note that when recording images on the surface of the transfer paper (when the number of originals for which image recording has been completed is an odd number), the paper is fed and ejected from the selected paper cassette. The paper is sent to the duplex unit 134, and in the case of image recording on the back side (when there is an odd number of originals), the paper is fed from the duplex tray 133 and discharged to the discharge tray 118. When image recording is completed, the original is ejected to the original document receiver 413 by the ADF 130, and the next original is fed (S
5). On the other hand, when a blank document is detected by the blank page detection process, it is determined that this is a slip sheet, and if the number of documents on which images have been recorded up to this point is an odd number (S6), only the front side of the double-sided tray is imaged. The recorded transfer paper is re-fed and discharged without recording an image on the back side (S7). These processes are not performed if the number of documents is even. In either case, the interleaf sheet on the contact glass is ejected to the document receiver 413 by the ADF 130 (S8), and the next document is fed (this is counted as the first document when counting the number of documents thereafter). In this way, image recording operations are performed one after another.A
The process ends when the image recording of all the originals in the original table 1 of the DF is completed. Note that even after image recording of all original documents is completed, if there is any transfer paper in the double-sided tray 133, it is ejected.

Effects As described above, according to the present invention, even when a plurality of document groups are stacked and set in the ADF at once and fed continuously without the operator's intervention, the previous document group It is possible to prevent a problem in which the last original of the previous original and the first original of the subsequent original are copied onto the front and back sides of the same transfer paper.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing the overall schematic configuration of an example of a copying system to which the present invention is applied, FIG. 2 is an explanatory diagram showing the flow of image signals in this device, and FIG. 3 is an illustration of the operation panel of this device. FIG. 4 is a sectional view showing the structure of the automatic document feeder, and FIGS. 5 and 6 are flowcharts showing the operation flow of the embodiment of the present invention. 10 ・ Digital copying machine (image recording device) 12 ・
Original reading section 13 Writing sections 1 and 4 / Image forming section 10] Photosensitive drum 110 Image reading plate 110a - Image reading element 118 ... Sorter 130 - Automatic document feeder (ADF) 131 - Switching claw 133 Double-sided tray 134・Double-sided unit 201.203・Image processing unit (IPU) 202-
Image memory 205 Main control board 301 - Operation panel 302 - Print key 312 Sheet detection mode key

Claims (1)

[Scope of Claims] An automatic document feeder that continuously feeds originals one by one from a stack of originals to the original reading unit, and a double-sided tray that temporarily receives transfer paper that has been recorded on one side and refeeds it for recording on the other side. In a digital image recording device equipped with a double-sided copying device having a double-sided copying device, when a document is fed by the automatic document feeder from a stack of documents stacked with multiple document groups, the It has a slip sheet detecting means for detecting that paper has been fed, and a means for counting the number of fed original sheets, and when a slip sheet is detected by the slip sheet detecting means in the double-sided copy mode, the counting means If the number of sheets in the previous document group is an odd number according to the count value, at that point, the single-sided copied transfer paper on the duplex tray of the above-mentioned duplex copying device is ejected outside the machine without copying the back side, and the interleaving paper is An image recording apparatus characterized in that control is performed so that subsequent documents fed next are processed in a double-sided copy mode, regardless of whether the number of documents in the group of documents immediately before the interleaving sheet is an odd number or an even number.