JP3240809B2 - Digital copier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder and a digital copying machine which reads a document image set on a document table by manual operation and forms an image on a sheet in accordance with the read image data.

[0002]

2. Description of the Related Art In recent years, digital copiers that read a document image set on a document table and form an image on a sheet in accordance with the read image data have become widespread. In such a digital copying machine, since a document image is converted into image data and handled as image data, processing such as rotation of the document image can be performed relatively easily.

[0003] By the way, the orientation of paper, such as the size and length and width of the paper used in a copying machine, varies widely. For example, four types of B5, A4, B4, and A3 can be considered even if the metric series has a standard size and is relatively frequently used. Considering the paper orientation (vertical and horizontal with respect to the paper transport direction), It is necessary to support six types of combinations of sizes and directions. However, the number of paper feed ports of a copying machine is limited, and it is impossible to always set sheets of all sizes and orientations. Therefore, the paper of each size and direction is selected in consideration of the frequency of use, and the paper with the high frequency of use is set in the paper feed port in advance.
If the user does not set the paper of the desired size and orientation, the user needs to set the paper again in the paper feed port.

In order to solve such inconveniences, Japanese Patent Laid-Open Publication No. 3-68267 discloses a digital copier that takes advantage of the characteristic that the image can be easily rotated, and that the orientation of the original image and the paper is one. When you are not
An apparatus has been proposed in which a document image is rotated by 90 degrees and the direction of the document image is made to match the direction of the set sheet to output the document.

[0005]

A digital copying machine having such an image rotation function has the advantage that copying can be performed irrespective of the paper orientation, but the image rotation function is used for all copying. Causes the inconvenience that if the user intentionally tries to copy the original image in the wrong orientation of the paper, the copying is performed against the user's intention. An object of the present invention is to solve such a disadvantage.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention reads an image of a document set on a document table by an automatic document feeder and a manual operation, and forms an image on paper in accordance with the read image data. A digital copying machine, comprising: a document detecting means for detecting a direction of a document image set on a document placing table; a paper detecting means for detecting a direction of a sheet forming a document image; The document image detected by the detection means is compared with the orientation of the paper, and if they do not match, the read image data is rotated to match the orientation of the document image and the paper. Determining means for determining whether or not the original image is a document image set by the automatic document feeder, and determining that the original image is set by the automatic document feeder by the determiner. In the case where the rotation processing is performed by the rotation unit, the control unit is configured to prohibit the rotation processing by the rotation unit when it is determined that the document image is not set in the automatic document feeder. It is characterized by.

[0007]

According to the digital copying machine of the present invention, when a document image is set on the document table by the automatic document feeder, the document image is compared with the orientation of the paper. Is rotated to match the orientation of the original image and the paper. Further, when the original image is not set on the original table by the automatic original feeder, that is,
When a document image is set by a manual operation, the image is not rotated even if the orientation of the document image and the paper do not match.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a digital copying machine according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a diagram showing a schematic configuration of a digital copying machine. The original to be copied, with the image side facing down,
The document is set on the document table 19, and the set document is read and output on a sheet. The digital copying machine includes a document feeder 500 (hereinafter, referred to as an ADF) that feeds and sets documents one by one on a document table 19, and an image reading device that reads a set document image and generates image data. The apparatus includes an apparatus IR and a printer PR that receives image data from the image reading apparatus IR and forms an image on a sheet.

The ADF 500 is provided on the upper part of the copying machine so as to be openable and closable. It is constituted by a paper tray 508 and the like. A plurality of documents can be placed on the tray 501 in a stacked state with the image to be copied facing upward. The placed originals are fed one by one from the bottom layer by the pickup roller 502, separated by the separating roller 502 and the separating pad 504, and then reversed along the transport path. The inverted document is conveyed onto the document table 19 via the registration roller 505 and set, and the image is read by the image reading device IR. After the reading is completed, the document is conveyed by a conveyance belt 506 and is discharged onto a discharge tray 508 via a reversing roller 507. In the case of a double-sided document, the document is returned to the document table 19 by making one rotation around the reversing roller 507. for that reason,
The transport belt 506 can be rotated forward and backward. Also,
A sensor SE3 for detecting whether or not a document is set is provided on the document placing tray 501.
A sensor SE4 is provided in the middle of the conveyance path from the document tray 501 to the document table 19, and detects the size and orientation of the document based on the detection time of the document being conveyed. Here, a state where the long side of the document is set in parallel with the document feeding direction is defined as a vertical direction, and a state where the document is set vertically is defined as a horizontal direction.

When copying without using the ADF 500, the user sets the ADF 500 in the open state,
A document is set on the document table 19 by manual operation, the ADF 500 is closed, and copying is performed. Even in this case, the size and orientation of the document placed on the document placing table 19 can be identified. ADF500
The outer peripheral surface of the transfer belt 506 (the surface facing the document table 19) is colored in orange, and the irradiation light of the transfer belt 506 by the exposure lamp 12 has a color with a small spectral sensitivity for the line sensor 17. The document table 19
It is possible to identify in which area the original is placed,
Thus, the size and orientation of the document can be detected.

The image reading device IR includes a scanning optical system 10 for scanning a document image to generate image data, and a scanning optical system 1.
The image data processing unit 20 processes the image data transmitted from the printer unit 0, and outputs the image data transmitted from the image data processing unit 20 to the printer PR as print data as it is, or temporarily stores the image data in a memory. It comprises a memory unit 30 for switching.

The scanning optical system 10 is provided below the document table 19 and has a first scanner 11 for holding an exposure lamp 12 and a first mirror 13a, and second mirrors 13b and 13b.
c, an imaging lens 15, a mirror 16, and a CCD in which a plurality of image sensors are arranged in a line.
It comprises a line sensor 17 and a motor M2.
The scanners 11 and 14 are each driven by a motor M2, and a line sensor 17
Move in the arrow b direction (sub-scanning direction) orthogonal to the arrangement direction (main scanning direction). By this movement, the document table 19
The document image set above is scanned and read.

The image data processing unit 20 and the memory unit 30 will be described later in detail.

The printer device PR includes a memory unit 30
A print processing unit 40 that drives an optical system 60 based on print data transmitted from the optical system 60; an optical system 60 that scans a laser beam emitted from a semiconductor laser 61 onto a photosensitive drum 71; The image forming system includes an image forming system 70 that performs an image forming process such as development and transfer of the formed latent image, and a sheet conveying system 80.

The print processing unit 40 includes an image reading device I
Receive print data from R, and based on the print data,
The light emission of the semiconductor laser 61 is controlled.

An optical system 60 includes a semiconductor laser 61 modulated (on / off) by the print processing unit 40.
A polygon mirror 62 that deflects and scans a laser beam emitted from the semiconductor laser 61; an fθ lens 63 that corrects distortion and the like of the deflected laser beam; and a mirror 64a that guides the laser beam onto the photosensitive drum 71 ,
64b and 64c.

The image forming system 70 includes a photosensitive drum 71 which is driven to rotate in the direction of arrow c, and a charging charger 72, a developing device 73, a transfer charger 74, a paper separating charger 75, a cleaner 76, Eraser lamp 7
7 are arranged.

The laser beam emitted from the optical system 60 and modulated in accordance with the print data is supplied to the charging charger 72.
Scans the surface of the photoreceptor uniformly charged in a linear manner, and forms an electrostatic latent image corresponding to the original image on the surface of the photoreceptor drum 71. The electrostatic latent image formed in this manner is
Is transferred by a transfer charger 74 onto a sheet conveyed by a sheet conveying system 80 described later. After the transfer, the surface of the photosensitive drum 71 is
After the cleaning, the residual charge is erased by the eraser lamp 77, and the charged charger 72 is again charged.
To form an image.

The paper transport system 80 includes a paper feed cassette 81a,
81b, paper feed rollers 82a, 82b, paper conveyance path 83,
Timing roller 84, transport belt 85, fixing device 86,
It comprises a discharge roller 87 and a paper discharge tray 88. The paper feed cassettes 81a and 81b can store B5 and A4 size paper in both portrait and landscape directions, B4 size paper in portrait orientation, and A3 size paper in portrait orientation. Paper is stored in a stacked state in either direction. The size and orientation of the accommodated paper are detected by sensors SE1 and SE2. Here, a state in which the long side of the sheet is set parallel to the sheet feeding direction is defined as a vertical direction, and a state in which the sheet is set vertically is defined as a horizontal direction. The paper in the paper feed cassettes 81a and 81b is
The paper is sequentially fed one by one by 82b, and is conveyed to a timing roller 84 along a conveyance path 83. The timing roller 84 sends out the sheet to the transfer unit in synchronization with the image formed on the photosensitive drum 71. The sheet on which the image has been transferred is sent to a fixing device 86 by a conveyance belt 85, and after the image is fixed by the fixing device 86, the sheet is discharged onto a discharge tray 88 by discharge rollers 87. The paper transport system 80 and the photosensitive drum 71 are driven by a main motor M1.

Next, the control section of the digital copying machine will be described. FIG. 2 is a block diagram showing a part of the control unit of the digital copying machine according to the present invention. The image data processing unit 20 includes a microcomputer (hereinafter, referred to as a CPU) 21 that controls the timing of the entire copying machine,
A / D converter 22, shading correction unit 23, gradation correction unit 24, scaling unit 25, line buffer 26,
It comprises a binarization processing section 27, an address decoder 28, and a document area detection section 29. An image reading synchronization signal is supplied from the CPU 21 to the line sensor 17, the image data processing unit 20, and the print processing unit 40.

The signal read for each line by the line sensor 17 is analog data, and the analog data is converted by the A / D converter 22 into digital image data of 8-bit gradation for each pixel, and the analog image data is subjected to shading correction. Tone correction such as MTF correction and gamma correction and well-known image processing such as scaling are performed. CPU in the scaling unit 25
Data thinning (at the time of reduction) and interpolation between pixels (at the time of enlargement) are performed on image data of one line in the main scanning direction in accordance with the magnification signal from 21. The line buffer 26
The image data for one line is stored. The image data output from the scaling unit 25 is stored line by line, and is sequentially output to the document area detection unit 29 or the binarization processing unit 27.

The document detector 29 detects the length and width of a document set on the document table 19 when copying is performed without using the ADF 500. In the case of copying without using the ADF 500, preliminary scanning is performed prior to reading scanning for image copying. The image data read by this preliminary scanning is input from the line buffer to the document area detecting section 29, and the document area is detected based on the image data, and the length and width of the document are determined. Specifically, the document image data from the line buffer 26 is binarized by a binarization circuit (not shown) in the document region detection unit 29,
The number of black pixels (corresponding to the area where the original is not placed on the original placing table 19) is counted for each line by a counter (not shown) in the original area detection unit 29, and the position information of the end point of the original is thereby obtained. Is taken into the memory in the CPU 21. This is disclosed in Japanese Unexamined Patent Publication No.
Since the technology already known in Japanese Patent Publication No. 8060 is adopted, the details of the circuit configuration are omitted. As shown in FIG. 4, an X, Y coordinate system is assumed on the platen glass 19 with the reference O on the right side in front of the platen glass 19. The X axis is parallel to the sub scanning direction, and the Y axis is parallel to the main scanning direction. The original is placed on the basis of O, and the original area detection unit 29 detects the coordinates X1, Y1 of the pixel corresponding to the end of the original.
Is detected. That is, as is apparent from FIG.
The size (vertical length) Dx in the direction and the size (horizontal length) Dy in the Y direction correspond to the coordinates X1 and Y1.

The image data read by the reading scan of the image copy is output from the line buffer 26 to the binarization processing section 27, where it is binarized. The binarized image data is written into the image memory 31 of the memory unit 30 in accordance with the write address specified by the address recorder 28, and the image data for one screen of the original image is developed. The address recorder 28 is a CPU 2
1 is decoded and given to the memory unit 30. As will be described later, the designation of the address from the CPU 21 is controlled by the comparison result of the orientation of the document and the paper, and the memory unit 30 31
Will be rotated.

The image data written in the image memory 30 is read in accordance with a read address specified by the address decoder 28, and is read by the print processing unit 40.
Is transferred as print data. Here, the laser diode 61 is driven based on the print data that has been D / A converted by the D / A converter 41 and then D / A converted by the LD drive unit 42.

In the figure, SW1, SW2, and SW3 are dip switches, which are used for setting a copy mode at the time of initial setting of a copying machine, which will be described later.

The CPU 21 controls the input and display of signals from various operation keys on the operation panel 90, and the settings on the operation panel 90 are stored in a memory inside the CPU 21. The operation panel 90 is configured as shown in FIG.

Reference numeral 900 denotes a numeric keypad, which is operated when setting the number of copies and setting the copy magnification. The set number of copies and the copy magnification are displayed on the display unit 901. 90
Reference numeral 2 denotes a key for selecting a desired copy magnification from the copy magnifications displayed on the magnification display portion 903. Each time the key 902 is pressed, the selected magnification is switched.

Reference numeral 904 denotes a copy paper size selection key.
Paper cassette 8 displayed on the copy paper size display area
One is selected from the paper sizes and orientations stored in the paper cassettes 1a and 81b (the size of the copy paper set in the paper feed cassettes 81a and 81b and the size of the copy paper other than those are displayed separately). Is the key to Each time the key 904 is pressed, the selected paper size and orientation are switched. Here, the paper cassette 8
1a, 81b, A4 vertical (A4T) and A3 vertical (A3T)
Are stored, and the A4 portrait is currently selected.

906 is an automatic paper selection (APS) mode,
The key is used to select an automatic magnification selection (AMS) mode or a manual (manual) mode in which paper selection and magnification selection are performed manually. Each time the key 906 is pressed, the selected mode is switched. Here, the APS mode is a mode in which the original size and orientation are detected, the optimum paper size and orientation are automatically selected from the detected original size and orientation and the set copy magnification, and copying is performed. is there. Also, A
The MS mode is a mode in which a document size is detected, an optimum copy magnification is automatically set from the detected document size and the set paper size, and copying is performed. APS, AM when power is turned on or when reset (initial setting)
Which mode of S or manual is selected is set by the dip switches SW1, SW2 and SW3.

Reference numeral 901 denotes a message display unit, which displays a set value of the number of copies, a numerical value of a copy magnification, and various warnings. Reference numeral 916 denotes a copy start button for starting a series of copy operations.

Next, the memory unit 30 will be described. The memory unit has a capacity to store 50 pages of A3 size originals. FIG. 5 shows an image memory 31 for one page. At the same time, an A4-size original placed as shown in FIG.
It shows the state when it is expanded above. Image memory 31
A two-dimensional address is set corresponding to one A3-size copy sheet, and an x address corresponds to the sub-scanning direction and a y address corresponds to the main scanning direction. x is 0 to x0,
y is set from 0 to y0. A similar image memory is provided for another 49 pages. Assuming that the copy magnification is M, there is a relationship between the XY coordinate system of FIG. 4 and the xy coordinate system of FIG.

[0033]

According to the digital copying machine of the present invention, when copying using the ADF 500, even if the manual mode is selected, the orientation of the document and the user Compare the paper orientation set on the operation panel. By this comparison, if the orientations of the original and the paper do not match, it is determined that the user has made a mistake in selecting the paper, and when the read image data is expanded on the image memory 31, the image data is rotated by 90 degrees and expanded. Control to do. As a result, the original image is copied in a state in which the orientation of the paper matches the orientation of the paper, and erroneous copying is prevented.

FIGS. 6 and 7 show C for executing the above control.
4 shows a processing flow of the PU 21.

Various settings on the operation panel 90 such as a copy mode, paper selection, and magnification selection are completed, and a copy start button 916 is displayed.
Pressing starts the image reading operation. First, in step 601, the presence or absence of a document on the tray 501 of the document table is detected by the sensor SE3, and it is determined whether the ADF 500 is used (YES in step 601) or not (step 60).
1 and NO). When using the ADF500, step 602
The document is conveyed and set on the document table 19. At this time, the size of the original (vertical and horizontal lengths Dx, D
y) is detected. On the other hand, when the ADF 500 is not used, a preliminary scan of the document is performed in step 603, and the document area detection unit 2
In step 9, document sizes Dx and Dy are detected. Step 604
Then, the copy mode selected by the copy mode selection key 906 on the operation panel 90 is determined. When the manual mode or the APS mode is selected, at step 605, the magnification selection key 902 or the ten-key
The copy magnification M selected at 0 is read, and step 6
At 06, it is determined whether the mode is the manual mode or the APS mode. In the manual mode, the length Px, y of the sheet selected in step 607 in the x direction in FIG.
The length Py in the direction is read, and in step 608, according to the determination of YES or NO in step 601, YES,
Branch in the direction of NO. That is, if the copying is performed using the ADF 500, the process proceeds to step 609. If the copying is performed without using the ADF 500, the process proceeds to step 619.

In the case of copying using the ADF 500, in step 609, the orientations of the sheet and the original are compared. That is, if the paper and the original are in portrait orientation, the difference in length and width (Px−Py)
And Dx-Dy) both indicate positive values, and if the paper and the original are in landscape orientation, the differences in length and width both indicate negative values. Therefore, the direction of the sheet and the original are compared by determining whether the value of (Px−Py) · (Dx−Dy) is positive or negative. If the orientation of the document does not match the orientation of the paper (YES in step 609), Px in step 610
And the value of Py are exchanged, and the image rotation flag R is set to 1. If it is determined in step 609 that the orientations of the sheet and the document match (NO in step 609), the flow directly proceeds to step 619.

When the APS mode is selected in step 606, paper sizes Px and Py that can be copied without image loss are calculated in step 611 from the document size and the set magnification.
In step 2, a cassette accommodating a sheet of a corresponding size and the direction is selected from the cassettes 81a and 81b.

If there is an appropriate cassette in step 613 (YES in step 613), the process directly proceeds to step 619, but if there is no appropriate cassette (NO in step 613), Px and Py are determined in step 614. The values are exchanged, and the image rotation flag R is set to 1. Then, in step 615, the presence or absence of an appropriate cassette is determined. That is, here, by exchanging the values of Px and Py, it is determined whether there is a cassette that accommodates the paper of the same size as the paper calculated in step S611 but in a different direction, and there is an appropriate cassette. If so, select this. If there is an appropriate cassette (YES in step 615), the process proceeds to step 619; otherwise (NO in step 615), the flag R is reset to 0 in step 616, and the message There is no size paper. " After this step 616, the copy operation may be executed in AMS or manual mode by pressing the copy start button 916.

If the AMS mode has been selected in step 604, the sizes Px and Py of the selected paper are read in step 617, and step 618 is executed.
Then, the copy magnification M is calculated, and the routine goes to step 619. In step 619, a control signal (magnification signal) is output to the scaling processing section 25 based on the reading magnification M.

Next, in step 620, after the output of the line buffer 26 is set so as to be directed to the binarization circuit 27, a reading scan for copying an image is executed, and an original image is read line by line.

At step 621, the image rotation flag R is determined. When R = 1 (YES at step 621), at step 622, image data is written by designating a write address of the image memory 31 according to the following equation (2). That is, the coordinates (X, Y) of the read image data are converted into the coordinates (x, y) of the image memory 31 by using Expression 2, and the converted coordinates (x, y) are output to the address decoder. To expand the image data in the image memory 31.

[0042]

X = M · (Dx−Y) y = M · X As a result, the image data is developed in the image memory 31 while being rotated 90 degrees so that the original image matches the direction of the paper. Will be.

When R = 0 at step 621 (step 621 NO), at step 623, the image memory 31 is rotated in a state where the original image is not rotated according to the above-described equation (1).
Expand to

Steps 620 to 62 are performed until the reading scan is completed and all the image data is completely developed.
3 is repeated, and when the processing is completed, the flow branches to YES in step 624, and step 6 is executed in step 625.
Similarly to 08, according to the determination of YES or NO in step 601, the process branches in the direction of YES or NO. ADF500
In the case of copying using (YES in step 625),
Proceeding to step 626, the end of document reading is determined by detecting the presence or absence of a document on the document placing tray 501 with the sensor SE3. If the document to be read next is not on the document placing tray 501 and reading is completed (YES in step 626), the process proceeds to step 627. If the document to be read next is on the document placing tray 501 (step 626). NO), returning to step 602 again to repeat the processing described above.

In step 627, the image data in the image memory 31 is output as it is to the printer PR for the set number of copies, and the original image is reproduced on the paper. Then, the process returns after resetting the image rotation flag R in step 626.

As is clear from the above description, in the digital copying machine of this embodiment, the AD
When copying using F500, due to user setting mistake,
Even if the orientation of the original does not match the orientation of the selected paper,
This is determined in the processing of step 609 (step 6).
09, YES), and at step 610, the image rotation flag is set to 1
Is set, the image data read in the process of step 622 in FIG. 7 is rotated by 90 degrees and developed on the image memory 31. As a result, the original image is copied in a state in which the orientation of the paper matches the orientation of the paper, and erroneous copying is prevented.

When copying in the manual mode without using the ADF 500, that is, when copying an original in the manual mode by manually setting the original on the document table 19, it is determined in step 608 that this is the case. (NO in step 608), since the processing in steps 609 and 610 is skipped and not executed,
The image rotation processing in step 622 is prohibited, and the read image data is expanded in the image memory without being rotated (step 623). As a result, when the user intentionally copies the original and the paper in different directions, the original image is copied without rotating the original image.

Further, in the APS mode, in step 611, the size (length and width) of a sheet that can be copied without losing an image is calculated from the set copy magnification and document size, and the calculated sheet is calculated. Even if there is no cassette accommodated (NO in step 613), step 6
At 15, a cassette containing sheets of paper of the same size but of different orientations is selected, and at step S622, the image is rotated to match the orientation of the original image with the paper. As a result, if sheets of the same size as the document are stored in the cassette, the optimum sheet is automatically selected regardless of the orientation, and the usability of the user is improved.

In this embodiment, when the original image is written in the image memory, the original image is rotated by 90 degrees. However, the entire original image is written once in the image memory as it is, and then the image is written. It may be rotated 90 degrees.

[0050]

According to the digital copying machine of the present invention, when the original image is set on the original placing table by the automatic original feeder, the original image and the paper direction are compared, and when they do not match, the image is read. The image data is rotated so that the orientation of the original image matches the orientation of the paper. Also, if the original image is not set on the original placing table by the automatic original feeder,
That is, when an original image is set by a manual operation, the image is not rotated even if the orientation of the original image and the paper do not match. As a result, even when the user inadvertently sets the original and makes a copy, the copy is made in a state in which the orientation of the original image matches the orientation of the paper, thereby preventing erroneous copying. Further, when the user intentionally copies the document in a direction different from the orientation of the sheet, the user can copy the document as intended by setting the document on the document table by manual operation.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a mechanism of a digital copying machine.

FIG. 2 is a control block diagram of the digital copying machine.

FIG. 3 is a plan view of an operation panel of the digital copying machine.

FIG. 4 is a diagram showing a state of a document placed on a document placing table.

FIG. 5 is a diagram showing a state of a document image developed in an image memory.

FIG. 6 is a flowchart illustrating a control procedure of an image reading process.

FIG. 7 is a flowchart illustrating a control procedure of an image reading process.

[Description of Signs] 17: Line Sensor 19: Document Placement Table 21: Microcomputer (CPU) 29: Document Area Detector 500: Automatic Document Feeder (ADF)

Claims (1)

(57) [Claims] 1. A digital copier for reading a document image set on a document table by an automatic document feeder and a manual operation, and forming a document image on a sheet in accordance with the read image data. A comparison unit that compares the orientation of the original image set in the original with the orientation of the paper forming the original image. If the comparison result by the comparison unit does not match, the read image data is rotated to rotate the original image and the orientation of the paper. Rotating means for matching the document image, determining means for determining whether the document image set on the document placing table is a document image set by the automatic document feeder, and determining means for determining whether the document image is When it is determined that the document image is set, the rotation processing by the rotation unit is performed, and when it is determined that the document image is not set by the automatic document feeder, A digital copying machine, further comprising control means for prohibiting rotation processing by the rotation means.