JPH02291544A - Image reader - Google Patents

Abstract

PURPOSE:To detect the size of a document directly by detecting reflected light at a position corresponding to the standard length of a form in a main scanning direction and a subscanning direction based upon the document reference position of a transparent member where the document is mounted as a starting point. CONSTITUTION:A document pressure cover 8 is arranged above the transparent member where the document is mounted and the surface corresponding to the top surface of the transparent member consists of a white area and a black area which can be discriminated by a photoelectric converting element; and one corner of the transparent member is regarded as the document reference position S and an area which is transmitted through the transparent member and can be judged by the photoelectric converting element as a black area is formed at the document reference position S in the main scanning direction 8CY and subscanning direction 8CX. Then the reflected light at the position, corresponding to the standard length of the form in the main scanning direction 8CY and subscanning direction 8CX based upon the document reference position S of the transparent member as the starting point, in the area which can be judged as the black area by the photoelectric converting element is detected. Consequently, it is judged whether or not a specific document is of the standard size and the specific document size can be judged without calculation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image reading device, and particularly to an image reading device that detects the size of paper such as a manuscript.

[Prior art] As a conventional image reading device of this type,
The technique disclosed in Publication No. 74 can be mentioned.

The technique described above uses a document exposure device that includes a document table on which a document is placed and an optical system that moves relative to the document table to expose the document on the document table. A light-receiving element that receives light and outputs an output according to the light intensity; a comparing means that compares the output of the light-receiving element with a reference value unrelated to the document size; and detecting means for detecting a change in the output of the comparing means at that time, and a size for determining the size of the document placed on the document table based on the detection signal from the detecting means and indicating the size. and determining means for outputting a signal.

The above technology moves the document table and the optical system relative to each other before exposing the document, detects the change in the output of the comparison means at that time, and determines the size of the document placed on the document table based on the detection signal. are doing.

[Problem to be Solved by the Invention] Since the conventional image reading device is configured as described above, the document table and the optical system are moved relative to each other before the document is exposed, and the change in the output of the comparing means at that time is changed. Based on the detection signal from the detection means that detects the document size, the determination means determines the size of the document placed on the document table and outputs a size signal indicating the size. It will be determined whether or not it is installed. Therefore, even though standard-sized originals are often used, it is necessary to judge the condition of the entire surface of the document glass to determine the original size, which is necessary for determining the original size before exposing the original. It will take more time.

As a result, it took a long time to determine the size of the document.

Also, even if it takes a long time to judge the document size,
If the original is placed incorrectly and the original size is incorrectly judged, the reading operation will be performed based on incorrect information, which may cause copy errors in the case of a copying machine, for example. That is, even if it takes a long time to judge the document size, there is a possibility that it will simply be a waste of time.

Therefore, the present invention does not require calculating the size of the manuscript,
Another object of the present invention is to provide an image reading device that prevents malfunctions when a document is placed incorrectly.

[Means for Solving the Problems] The image reading device according to claim 1 is arranged above a transparent member on which a document is placed, and a surface corresponding to the top surface of the transparent member on which the document is placed is a photoelectric conversion element. A white area and a black area that can be read by
A document pressing force that presses the document, with two corners as the document reference position, and an area that is transmitted through the transparent member and readable as a black area by the photoelectric conversion element parallel to the main scanning direction and the sub-scanning direction at the document reference position. An area that can be read as black by the photoelectric conversion element of the cover and the document pressing cover corresponds to the standard length of the paper in the main scanning direction and sub-scanning direction starting from the document reference position of the transparent member on which the document is placed. an optical detection means for detecting reflected light at a position where the original is read, and when the optical detection means determines that the original is not placed at the original reference position of the transparent member on which the original is placed, the original is read. This prohibits entry into action.

In the image reading device according to a second aspect of the present invention, an area formed parallel to the main scanning direction and the sub-scanning direction that can be read as black by a photoelectric conversion element is defined as an abbreviation-shaped area.

In the image reading device according to claim 3, the arrangement of the abbreviation-shaped areas with respect to the transparent member is parallel to the main scanning direction and the sub-scanning direction, and the width of the transparent member is about 10 mm or less. .

In the image reading device according to claim 4, a plurality of regions formed parallel to the main scanning direction and the sub-scanning direction that can be read as black by the photoelectric conversion element are formed independently in the main scanning direction and the sub-scanning direction. It is something.

In the image reading device according to claim 5, the area formed to be parallel to the main scanning direction and the sub-scanning direction that can be read as black by the photoelectric conversion element is formed so that the surface of the document pressing cover on the transparent member side is the surface of the white area. It is formed as a frame of a black area surrounding three or more sides of.

An image reading device according to a sixth aspect uses a scanner included in the image reading device.

In the image reading device according to a seventh aspect of the present invention, the optical detection means for detecting the original is a photocoupler in which a photoelectric conversion element disposed at a predetermined position is used as a light receiving element.

In an image reading device according to an eighth aspect of the present invention, a polarizing filter is interposed in an optical detection means for detecting a document.

[Function] According to claim 1, the document pressing cover is disposed above the transparent member on which the document is placed, and the surface corresponding to the upper surface of the transparent member on which the document is placed is a white area readable by a photoelectric conversion element. and a black area, and one predetermined corner of the transparent member on which the original is placed is set as the original reference position, and an area that is transmitted through the transparent member and can be read as the black area by a photoelectric conversion element is defined as the original reference position. The area is formed to be parallel to the main scanning direction and the sub-scanning direction, and is readable as black by the photoelectric conversion element. By detecting the reflected light at a position corresponding to the standard length of the paper, it is determined whether the predetermined document is of the standard size of the paper, and the predetermined document size is determined without calculation. Then, when the original is not placed at the original reference position of the transparent member on which the original is placed, the reading function of the device equipped with the image reading device is stopped, and operations that may become unnecessary operations are stopped. It is something to do.

In claim 2, since the area formed to be parallel to the main scanning direction and the sub-scanning direction that can be read as black by the photoelectric conversion element is an abbreviated area, On the other hand, it is possible to detect the minimum distance, and the direction is the same as the direction in which the standard size length of the paper is determined, so there are few causes of judgment errors.

In claim 3, the substantially L-shaped area is arranged in parallel to the main scanning direction and the sub-scanning direction with respect to the transparent member,
Moreover, the width from the end of the transparent member is set to about 101III or less, and the margin space of a normal document is used as a reading space of the same size.

In claim 4, the area formed parallel to the main scanning direction and the sub-scanning direction that can be read as black by the photoelectric conversion element is a plurality of independently formed areas in the main scanning direction and the sub-scanning direction, and the area other than the detection position is It can be a white area.

In claim 5, the area formed parallel to the main scanning direction and the sub-scanning direction that can be read as black by the photoelectric conversion element is such that the surface of the document pressing cover on the transparent member side is located on three sides of the surface of the white area. By forming a frame of a black area surrounding the above, the area of the document pressing cover that is determined to be black is not limited to a substantially L-shape, but can be made into a concave shape or a square shape.

According to a sixth aspect of the present invention, a scanner included in the image reading device is used, and the document size can be detected without performing preliminary scanning by the scanner.

In claim 7, since the optical detection means for detecting the original is a photocoupler whose light receiving element is a photoelectric conversion element disposed at a predetermined position, it is not necessary to use a scanner as an image reading device. Since there is no paper size, it is possible to detect the document size without performing preliminary scanning with a scanner.

In claim 8, since a polarizing filter is interposed in the optical detection means for detecting the original, even if the same color can be recognized with the naked eye, the presence of the original is determined by the photoelectric conversion element as black. It is possible to judge the difference between the areas. Furthermore, even if a transparent original is used as the original, it can be clearly distinguished due to the difference in synthetic resin material.

[Embodiment] An example in which an image reading device according to an embodiment of the present invention is used in a copying machine will be described below.

FIG. 2 is an explanatory front view of main parts showing the general internal structure of a copying machine according to an embodiment of the present invention, and FIG. 3 is a front view of the entire copying machine according to an embodiment of the present invention. 4 are perspective views of the entire editor used in a copying machine according to an embodiment of the present invention.

The copying machine of this embodiment converts a document image read by an image sensor into image data, which is a digital signal, and prints an image on paper using electrophotography in accordance with this image data.

In FIGS. 2 and 3, the scanner 1 includes an exposure lamp 11 that irradiates the original, a rod lens array 12 that collects reflected light from the original, and a CCD that converts the collected light into an electrical signal. Color image sensor 1 consisting of
It has 3. The exposure lamp 11 for irradiating the original in this embodiment can be one that is normally used in copying machines, and does not require any special lamp.

The image sensor 13 of this embodiment has an accuracy of about <1/16 mm when installed, and has a common electrical and mechanical reference point. It has a mechanical adjustment means and/or an electrical adjustment circuit so that one pixel becomes a reference position for main scanning. Scanner 1 uses motor 2 when reading an original image.
The document on the document table 9 made of a transparent member on which the document is placed is scanned while being pressed by the document pressing cover 8 that presses the document.

The original image irradiated by the exposure lamp 11 is photoelectrically converted by the image sensor 13 and sent to the signal processing section 11'5.
is converted into a print signal of yellow, magenta, cyan, or black.

In the print head section 16, a semiconductor laser driver (not shown) operates according to a print signal for each color from the signal processing section 15, and the semiconductor laser blinks. A laser beam generated from the semiconductor laser is reflected by a reflecting mirror 18 via an fθ lens 17, and exposes the photoreceptor drum 4. The surface of the photosensitive drum 4 is uniformly charged by a charging charger 19, and an electrostatic latent image is formed by receiving the above-described exposure.

This electrostatic latent image is developed into yellow, magenta, cyan, or black by one of the developing devices 20a to 20d. The developed image is transferred by the transfer charger 22 onto a sheet of paper wrapped around the circumferential surface of the transfer drum 5.

After the above-mentioned process is repeated for at least one color of yellow, magenta, cyan, or black, the paper is separated from the transfer drum 5 by the separating claw 25, fixed by the fixing device 6, and placed on the paper output tray 26. Paper is ejected. During this time, the scanner 1 repeats scanning in synchronization with the rotational operations of the photosensitive drum 4 and the transfer drum 5. The transfer drum 5 is provided with a position sensor 23, and is controlled to synchronize with the scanner 1 based on this detection signal. Note that the paper is fed from the paper cassette 7, and its leading edge is chucked by a chucking mechanism 24 provided on the transfer drum 5, so that no misalignment occurs during transfer of each color. Note that the eraser lamp 21 is for erasing the latent image on the photosensitive drum 4.

These components are housed in a housing 10 that forms the outer shell of the copying machine main body.

As shown in FIG. 4, the editor 3 used in the copying machine of this embodiment includes a coordinate input tablet 30, a stylus pen 31 manually operated on the coordinate tablet 30, a select key 32 for selecting paper, a manual key 33, It has a liquid crystal display section 34 etc. that displays the input state.

FIG. 5 is a schematic block diagram of the entire control system of a copying machine according to an embodiment of the present invention. 6 is a schematic circuit diagram of an operation panel of a copying machine according to an embodiment of the present invention, FIG. 7 is a schematic circuit diagram of an editor, and FIG. 8 is a schematic circuit diagram of a reading section. Similarly, FIG. 9 is a schematic circuit diagram of the printing section.

In FIG. 5, the central controller 50 includes an operation panel section 60, an editor section 70, and an image reader section 8.
0. Overall control of the printing unit 90 by serial signals,
Performs overall control of the copying machine. The operation panel 60 is a panel for mainly inputting keys for operating the copying machine, the editor section 70 performs editing input, and the image reader section 80 reads a document and converts it into an image signal. The printing unit 90 records image signals on paper.

Here, an operation panel section 60, an editor section 70
, the image reader section 80, and the printing section 90 will be described in detail.

The operation panel section 60 includes a microcomputer 61 and a clock generation circuit 62 for driving the microcomputer 61, and is connected to a command bus via a driver 63 and a receiver 64. Further, the microcomputer 61 is connected via a display driver 65 to a liquid crystal display section 66 for displaying messages. The microcomputer 61 uses a decoder 67 as a scanning signal and inputs the operation of a touch key 68 formed together with the diode matrix circuit.

The editor section 70 includes a microcomputer 71 and a clock generation circuit 72 that drives the microcomputer 71.
It has a driver 73 and a receiver 74 and is connected to a command bus. Further, the microcomputer 71 is connected via a display driver 75 to a liquid crystal display section 76 for displaying messages. Then, the microcomputer 71 uses a decoder 77 to generate a scanning signal, and converts the touch key 7 formed with the diode matrix circuit into a scanning signal.
8 operations are being input.

Further, connected to the microcomputer 71 are a coordinate doublet 30 for inputting the X and Y coordinates for editing the original to be copied, and a stylus pen 31 for instructing the X and Y coordinates.

The image reader section 80 has a microcomputer 81 and a clock generation circuit 82 for driving the microcomputer 81, and is connected to a command bus via a driver 83 and a receiver 84. Further, the microcomputer 81 drives and controls a scanner motor 86 that scans a document via a driver 85.

The microcomputer 81 also includes a lamp control section 801.
The exposure lamp 11 is turned on via the exposure lamp 11, and the document placed on the document table 9 is illuminated. The original image illuminated by the exposure lamp 11 is photoelectrically converted by the image sensor 13.
The color separation signal amplification section 811 converts the signal into red, green, and blue. The color-separated red, green, and blue color signals are A/D converted by a digitization processing section 812, and then sent to a shading correction section 813.
Then, sensitivity correction of the image sensor 13 and shading correction for correcting uneven light distribution of the exposure lamp are performed, and the data is converted into density conversion data by a density conversion unit 814.

Next, the unnecessary area processing unit 815 generates an explanatory diagram showing the relationship between the unnecessary area and the document size data (XP, xw, yp, 1) in FIG. 25, and an explanatory diagram showing the relationship between the unnecessary area and the document size data (XP, , XV, YF, Yw), the document size data (XP, XW.
Unnecessary areas are removed based on YP, YW). Here, the original size data (XP, YP) of the OHP paper in the diagram above
is set to "90" because the approximately L-shaped area 8C of the elastic pressing member 8B is pressed by the document pressing cover 8.
In order to prevent the data from passing through the OHP paper and becoming "black" data, "90" corresponding to the width of the abbreviated character area 8C is added to perform "white" data processing.

Note that the process of erasing the outside of the image area (replacing it with "white" data) by the unnecessary area processing unit 815 is performed on the image data before the scaling/movement processing unit 817, which will be described later. That is, this means, for example, that the original size A4T is
When reducing and printing on copy paper larger than 4T, if the process of erasing the outside of the image area by the unnecessary area processing unit 815 is performed after reduction, the elastic pressing member 8B of the original pressing cover 8
After unnecessary images due to dirt on the surface of the document are also reduced, areas outside the document size are replaced with white data, so unnecessary images are also printed in addition to the image of the reduced document.

In order to prevent this, it is necessary to take into account the magnification, the amount of movement, the document size, the printing paper size, etc., and make corrections, which requires complicated calculations, which results in a loss of calculation time. Therefore, as in this embodiment, the unnecessary area processing unit 81
If the process of erasing the outside of the image area in step 5 is performed before the processing of the scaling/movement processing unit 817, etc., such complicated calculations can be omitted, and the magnification, amount of movement, original size, and printing paper size can be It is possible to obtain a clean image output without being affected by such factors.

Next, the color correction unit 816 removes the undercolor from the image signals of red, green, and blue, that is, matches the characteristics of the developing toner to the image signals corresponding to each print color of yellow, magenta, cyan, or black. These yellow, magenta, cyan or black signals are generated. Furthermore, the output from which the unnecessary area has been removed by the unnecessary area processing unit 815 is input to the line memory 830 as image data for each line obtained by one main scan. The image data for each line entered into the line memory 830 is stored in the microcomputer 8.
1 can read it, and the image data at the time of reading the document can be placed in any position in the line memory 830 as specified by the microcomputer 81. The output of the color correction section 816 is subjected to a scaling/movement processing section 817 that sets a predetermined magnification and a position based on editing information, a filtering processing section 818 that performs filter processing such as predetermined edge processing and smoothing processing, and then a density adjustment section. 819 performs printing density processing, and furthermore, a pseudo halftone processing section 820
The data is subjected to dither processing and multivalue processing, and is output to the printing unit 90 via the output line buffer 821.

The printing unit 90 includes a microcomputer 91 and a clock generation circuit 92 that drives the microcomputer 91, and is connected to a command bus via a driver 93 and a receiver 94.

Further, the microcomputer 91 also includes a motor control circuit 95.
It is output to the polygon motor 16 via.

Output line buffer 821 of the image reader section 80
The image data outputted from is inputted via an image data I/F (interface) 96 to a laser diode driver 97 controlled by a microcomputer 91.
A laser diode (not shown) is caused to emit light via the .

The microcomputer 91 also includes an eraser control circuit 9
8 to control the eraser lamp 99. Furthermore, inputs and outputs of devices and sensors necessary for operating the copying machine of this embodiment are also connected.

Furthermore, in the above block configuration, in particular, the unnecessary area processing section 815 used in the embodiment of the present invention will be explained using a specific circuit example.

FIG. 10 is a specific circuit diagram of the unnecessary area processing section 815 used in the embodiment of the present invention.

In the figure, a counter COUNTI is used to designate addresses XAl2-0 for the document in pixels to be read in the main scanning direction, and a counter COUNT2 is used to designate addresses YAl2-0 for the document in pixels to be read in the sub-scanning direction.

At this time, the address of the document reference position is XAl2~
O=YAl2~o=ooo.

Also, comparator COMP1 to comparator COMP
4 generates an E-EN signal for erasing signals outside the document area, the comparator COMPI determines the reading start position in the main scanning direction, and the comparator COMP2
determines the reading end position in the main scanning direction. The comparator COMP3 determines the reading start position in the sub-scanning direction, and the comparator COMP4 determines the reading end position in the sub-scanning direction.

Therefore, comparator COMP1 to comparator CO
In MP4, XP12~O; Reading start address in the main scanning direction yP
l2~0 ; Reading start address in the sub-scanning direction X Wl2
~0; Reading width in the main scanning direction Y wl2~0; Reading width in the sub-scanning direction is input from the microcomputer 81.

In this way, the outputs of the comparators COMP1 to COMP4 become the E-EN signal for erasing signals outside the document area by the NAND gate NAND, and are input to the clear terminal of the D flip-flop D-F'P, and are input to the clear terminal of the D flip-flop D-PP. When the image data input to the D terminal of the image data is outside the document size, the image data output from the Q terminal of the D flip-flop D-PF becomes "white" data regardless of the input image data. .

That is, when the unnecessary area processing unit 815 detects the document size, if the area other than the document area is set to "white" data,
Since there is no need to perform wasteful printing processing, the address of the document size in the main scanning direction and the sub-scanning direction is detected for this purpose.

Note that the TG signal is a synchronization signal for each line in the main scanning direction, and is a timing pulse that generates one pulse when moving one step in the sub-scanning direction. The VD signal indicates the range of the original in the sub-scanning direction to be reproduced.

Next, the principle of an image reading apparatus according to an embodiment of the present invention will be explained using FIG. FIG. 1 is an explanatory diagram illustrating the principle when the image reading device of the present invention is implemented in a copying machine, and (a
) is a front view when the document pressing cover 8 is opened, (b)
(C) is a front view from the scanner 1 side when a plain paper document with a white background is placed on the document table 9. (C) is the document table 9.
FIG. 3 is a front view seen from the scanner 1 side when a transparent document POIIP such as an OHP is placed thereon. Further, FIG. 11 is a plan view of the document table 9 of the copying machine of this embodiment, and FIG. 12 is a plan view of the document P
FIG. 4 is an explanatory diagram showing the positional relationship between the document pressing cover 8 and the document P when the document pressing cover 8 and the document P are displaced.

In FIG. 1, the document pressing cover 8 includes a cover main body 8A formed by standing up a plate-shaped periphery of synthetic resin or the like into a frame shape, and an elastic pressing member 8 made of an elastic member disposed within the frame.
It is composed of B. Along the two sides of the elastic pressing member 8B, electrical detection means consisting of the main scanning direction 8CY and the sub-scanning direction 8CX, for example, in the above embodiment of the copying machine, the image sensor 13 determines that the color is black with a predetermined width. An abbreviated region 8C is formed. That is, one predetermined corner of the document table 9 made of a transparent member on which the document P is placed is defined as the document reference position S (see FIG. 11), and the abbreviated-shaped bending point is located at the document reference position S. A photoelectric conversion element such as an image sensor 13 is attached to an elastic pressing member 8B made of an elastic member disposed within the frame of the cover body 8A constituting the original pressing cover 8 for pressing the original P. It forms an abbreviation-shaped area 8C that is legible as black.

Note that, except for the abbreviated area 8C of the elastic pressing member 8B made of an elastic member disposed within the frame of the cover main body 8A forming the document pressing cover 8, there is a document table made of a transparent member on which the original P is placed. The substantially entire surface of the document table 9 corresponding to the upper surface of the document table 9 on which the document P is placed is formed so that it can be read as white by the image sensor 13 .

For example, as shown in FIG. 1(b), a plain paper document P is placed on a document table 9 made of a transparent member, aligned with the document reference position S. At this time, when the plain paper original placed on the original platen 9 is viewed from the scanner 1 side, the original P on the original platen 9 is pressed by the original pressing cover 8 that presses it, and the original P is pressed by the elastic pressing cover 8. The substantially L-shaped area 8C of the member 8B is hidden by the document P by a predetermined distance from the document reference position S. At this time, the main scanning direction 8CY and sub-scanning direction 8CX of the abbreviated area 8C hidden by the original P are determined depending on the type of the original P and the like.

When a transparent original POIIP such as OHP paper is placed on the original platen 9, when viewed from the scanner 1 side, the elastic pressing member 8
The abbreviated area 8C of B is not hidden.

Therefore, the originals P and O made of plain paper on the original table 9
In order to detect both the transparent original POIIP such as HP paper, the incident angle of the light source and the reflection angle on the light receiving side with respect to the original P or transparent original POIIP are set to be different from each other, and the It is necessary to detect scattered light. Therefore, in this embodiment, the original on the original platen 9 made of a transparent member on which the original is placed is scanned while being pressed by the original pressing cover 8, and the original P or transparent original P OI
The scattered light of the IP is detected by a color image sensor 13 composed of a CCD or the like that constitutes the scanner 1. Naturally, the approximately L-shaped area 8C of the elastic pressing member 8B is an image sensor formed on the original pressing cover 8 in order to receive only the scattered light of the plain paper original P and the transparent original POIIP such as OHP paper. 13, it is necessary to make the abbreviation-shaped area readable as black, and for this purpose, the abbreviation-shaped area usually needs to be made of a material that performs specular total reflection.

The original P is placed at the original reference position S on the original table 9 shown in FIG.
The specific corner is located, and the vertical side 9a and the horizontal side 9b of the document table 9 are parallel to each other, and direction side 9
The document size scale 9A along the horizontal direction a and the document size scale 9B along the horizontal side 9b are used to determine the document size and whether the current position is the normal position.If it is not in the normal position, the document P is I am correcting the position where it was placed. However, due to human error or the flow of air when operating the document pressing cover 8, the document P may not be placed at a predetermined regular position. Furthermore, depending on the mounting precision of the document pressing cover 8, the position of the predetermined position of the document table 9 and the abbreviated region 8C of the elastic pressing member 8B may be misaligned due to its rattling.

Therefore, the width of the abbreviated region 8C of the elastic pressing member 8B is about 5 mm when viewed from the scanner 1 side.

Also, at this time, the main scanning direction 8C of the abbreviated character area 8C
The error α in Y and the error β in the sub-scanning direction 8CX are set so that they can be absorbed by electrical processing.

Next, the operation when the image reading apparatus configured as described above is implemented in a copying machine will be described using flowcharts shown in FIGS. 13 to 19.

FIG. 13 is a flowchart showing the main program for the operation of the copying machine of this embodiment. Fig. 14 is a flowchart of the "reading/printing routine" called by the main program, Fig. 15 is a flowchart of the "trimming setting routine", Fig. 16 is a flowchart of the "magnification setting routine", and Fig. 17 is a flowchart of the "trimming setting routine". is also a flowchart of the "density setting routine". Also, FIG. 18 is a flowchart of the "unnecessary area setting routine".
FIG. 19 is a flowchart of the "density adjustment preliminary/scanning routine" as well.

This routine shows the main program for the operation of the copying machine of this embodiment, and is for selecting a predetermined mode by key operation.

First, this routine starts at the same time as the power is turned on, initial settings are made in step S1, and in step S2 the central controller 50, operation panel section 60, editor section 7
0. After confirming that no trouble has occurred in the image reader section 80 and printing section 90, wait for a predetermined warm-up time to elapse in step S5. If it is determined in step S2 that a trouble has occurred, the trouble is displayed on the liquid crystal display section 66, and in step S4 it is determined whether the trouble has been resolved and the reset has been performed. Then, the routine returns to step S1.

If it is confirmed in step S5 that the warm-up time has been slightly exceeded, it is determined in step S6 whether a key has been operated on the operation panel section 60 or editor section 70, and if a key has been operated, the key operation is performed in step S7. Determine the type. If the key type is a print key, a ``reading/printing routine'' is called in step S8, and if the key is an editor, a ``trimming setting routine'' is called in step S9. Further, in the case of a zoom key, a ``magnification setting routine'' is called in step S10, and in the case of a density key, a ``density setting routine'' is called in step Sll.

When the "reading/printing routine" is called by operating the print key, the program shown in the flowchart of FIG. 14 is executed.

This routine is used as a copying machine to read an image of a document and print the read image data.

It is determined in step S21 whether the automatic size detection mode is selected, and when the automatic size detection mode is selected, it is determined in step S22 whether trimming is specified, that is, whether the flag TRM is "1". When trimming is specified in step S22, the flag AE indicating automatic density adjustment mode is set to "1" in step 82B.
Determine whether If it is not the automatic density adjustment mode, the image of the document is read in step S32, the printing section prints according to the data, and this routine is exited.

In the automatic density adjustment mode, the image of the document is read in step S32, the print section prints according to the data, and this routine is exited. In the automatic density adjustment mode, the scanner 1 is moved to the rear edge of the document in step S24, and the "density adjustment preliminary scanning routine" for performing automatic density adjustment is called in step S25, and after performing preliminary scanning for automatic density adjustment, In step S32, the image of the document is read, the printing section prints according to the data, and this routine is exited.

That is, when trimming is specified, step S
26, ``Do not call document size detection routine J. Enter automatic density adjustment mode judgment.''

If trimming is not specified in step S22, a "document size detection routine" to be described later is called in step 826 and executed, flag A and flag B are checked in step S27, and if either flag A or flag B is " If the original size is not 0'', that is, if the document size has been successfully detected, an ``unnecessary area setting routine'' is called in step S28, and unnecessary area setting is performed. Next, in step S29, the flag AE indicating automatic density adjustment mode is set to "1".
Determine whether When the automatic density adjustment mode is not set, it is determined in step S30 whether the scanner 1 is at the home position, and if it is not at the home position, the scanner 1 is returned in step S31, the image of the document is read in step S32, and the print section is moved according to the data. to print and exit this routine.

Flag AE indicating automatic density adjustment mode in step S29
is "1" and the mode is automatic density adjustment, it is determined in step 333 whether the scanner 1 is at the rear edge of the document,
When the scanner 1 is not at the rear edge of the document, the scanner 1 is moved to the rear edge of the document in step 834, the "density adjustment preliminary scanning routine" is called in step 335, automatic density adjustment preliminary scanning is performed, and then the scanner 1 is moved to the rear edge of the document in step S32. The image of the document is read, the printing section prints according to the data, and this routine is exited.

Also, looking at flag A and flag B in step S27,
When either one is "0", that is, when the original size detection is not performed well, the flag C is set to "0" in step S36.
1" and flag D is "0" indicating a main scanning error, or in step 337 flag C is "0" and flag D is "1".
In step 338, it is determined whether there is a sub-scanning error, and if there is an error, the liquid crystal display unit 66 displays that the size cannot be detected in step 338, and exits from this routine. Further, if it is determined in step S36 that there is no main scanning error and in step S37 that there is no sub-scanning error, the liquid crystal display unit 66 displays a message indicating that a modified size document has been detected in step S39.
The process begins in step S40.

Next, or when it is determined in step S21 that the automatic size detection mode is not selected, key manual input for the document size is requested in step S40, and when key manual input is confirmed in step S41, key manual input is requested in step S42. The specified size is determined, and the process proceeds from step 843 to step S4.
7, if the specified size is A3T, if flag A←1, flag B←4, if A4Y, if flag A←1, flag B←2, if A4T, if flag A←2, flag B←3, if A5Y , flag A←
2. If flag B ← 1, A5T, set flag A ← 3, flag B ← 2, and in step S48 request key input for the document type, whether the document is plain paper or OHP paper; When key manual input is confirmed in step S49, the type of manuscript for which key input was performed is determined in step S50, and the OH
When the paper is P, the flag E is set to "1" in step S51,
When the paper is plain paper, the flag E is set to "0" in step S52, and the routine returns to step 328.

Next, a flowchart of the "trimming setting routine" will be explained.

In this routine, a predetermined area is selected by the editor 70, and that area is set as a copy target.

In step S61, it is determined whether the settings are valid by determining the settings of the editor 70, for example, whether the setting procedure is correct, whether the area is zero, etc., and when the settings are valid, in step S62 Set trimming area data (XP, XW, YP, YW) in the unnecessary area setting section. At step 863, the flag TRM is set to "1" to memorize the fact that trimming is to be performed, and this routine is exited. Also, when the settings of the editor 70 are not valid,
In step S64, an error message is displayed on the liquid crystal display section 76, and in step S65, the flag TRM is set to "0" to remember that no trimming settings have been made.
L, exit this routine.

Next, a flowchart of the "magnification setting routine" will be explained.

This routine sets the magnification of a predetermined copy target.

In step S71, it is determined whether the magnification setting is valid, for example, whether the magnification is within the copyable range of a predetermined designated sheet, and if it is not valid, this routine is exited. When it is valid, magnification data is set in the magnification/movement processing section in step S72, and this routine is exited.

Next, a flowchart of the "density setting routine" will be explained.

In this routine, the density of a predetermined copying object is set by sampling detection.

In step S81, it is determined whether the density setting is valid, for example, whether the density is within a predetermined copyable range, and if it is not valid, this routine is exited. When it is valid, it is determined in step S82 whether the automatic density adjustment key is operated;
When the operation is being performed, the flag AE for storing that the automatic density adjustment mode has been selected is set to "1", and this routine is exited.

Further, when it is determined in step S82 that the automatic density adjustment key has not been operated, the flag AE for storing that the automatic density adjustment mode is not selected is set to "0", and in step S85 the density adjustment section is manually operated. Outputs the concentration setting signal specified by and exits from this routine.

Next, a flowchart of the "unnecessary area setting routine" will be explained.

In this routine, only an area of a predetermined document size is targeted for copying and/or density detection, and this area is determined here.

In step S91, it is determined from the flag TRM that the flag TRM is set to "1", and if trimming designation is selected, unnecessary areas are removed by trimming, and this routine is exited. If no trimming setting has been made, the value of flag A is determined in step S92, and if flag A=3, an area of A5T is set as the original size in step 893. When flag A=1, the value of flag B is determined in step S94, and flag B
If =2, A4Y is set as the document size in step S95.
If flag B=4, an area of A3T is set as the document size in step S96. Then, when flag A=2, the value of flag B is determined in step 897, and if flag B=1, step 39
8, set the A5Y area as the original size, and
If flag B=3, an area of A4T is set as the document size in step S99. Next, step S100
The flag E indicating that OHP paper is selected is “
1". When OHP paper is selected, the area for OHP paper is specified in step SIO1. In other words, when OHP paper is used as a document, the abbreviation-shaped area 8C is selected during reading scanning. To prevent the area from being read as black, a process is performed to make the 5 mm width of the abbreviated character area 8C white, and this routine is exited.

Next, a flowchart of the "density adjustment preliminary scanning routine" will be explained.

This routine detects density data by sampling only an area within a predetermined document size or an area designated for trimming.

A sampling area for reading density data to be automatically adjusted is calculated from the document size automatically read or manually set in step S111 or the trimming area data set in step S9. Step S112
In step 8113, the scanner 1 is returned, that is, the movement direction of the scanner 1 is changed from forward scanning to detect the original size to backward scanning, and in step 8113, the automatic density adjustment calculated in step S111 is performed. It is determined whether the density data sampling reading area is entered, and when the area is entered, the reading data is loaded into the line memory 830 in step S114, and the sampling data of the reading area to be automatically adjusted in density is read from the line memory 830 in step S115. Read out. The operations from step S114 to step S115 are performed in step S116.
This continues until the reading area is out of the reading area for which the automatic density adjustment calculated in step 11 is to be performed. When it is determined in step 8116 that the scanner 1 is out of the reading area where automatic density adjustment is to be performed, it is determined in step S117 whether the scanner 1 is at the home position, and when the scanner 1 reaches the home position, the scanner 1 is stopped in step 8118. , step S1
19, in step S115 the line memory unit 830
The optimum density adjustment level is determined by determining the density read from the image data, and outputs it to the density adjustment section 820 in step S120.

Furthermore, the image reading operation when the image reading apparatus of this embodiment is implemented in a copying machine will be explained using the flowcharts of FIGS. 20 to 24.

FIG. 20 is a flowchart of the "original size detection routine" which corresponds to the main program of the image reading device used in the copying machine of this embodiment. FIG. 21 is a flowchart of the main scanning direction detection subroutine used therein.
FIG. 22 is a flowchart of the sub-scanning direction data reading subroutine J, FIG. 23 is a flowchart of the sub-scanning direction detection subroutine, and FIG. 24 is a flowchart of the r size determination subroutine.

First, the flowchart of "r Original Size Detection Routine" will be explained.

This routine scans the scanner in the forward direction to detect image data at specified positions in the main scanning direction and sub-scanning direction, and when the document size in the main scanning direction or sub-scanning direction is detected or cannot be detected. When a flag is used, it is stored in a flag.

When this routine is called in step S26, in step S201 the scanner 1 starts scanning in the forward direction away from the document reference position S, and in step S202 it is determined whether the scanner 1 is at the document reference position S1, that is, the document leading edge position. When the scanner 1 reaches the document reference position S, the r main scanning direction detection routine is called. Then, in step S204, it is determined whether flag A, which means that nothing was detected in the main scanning direction, is "0". When nothing is detected in the main scanning direction, the scanner 1 is returned to the home position in step S205,
In step 8206, the flag C, which means that detection was not possible in the main scanning direction, is set to "1", and the flag D is set to "0".
to exit this routine.

Therefore, if detection in the main scanning direction is not possible, the detection operation in the sub-scanning direction from the next step onward is not performed. Therefore, unnecessary sub-scanning can be prevented when the size cannot be detected.

If it is determined in step S204 that detection in the main scanning direction is possible, the scanner 1 is moved to the specified position D1 calculated from the paper specifications in step S207, and the "sub-scanning direction data reading subroutine" is executed in step 8208. Call and read the data in the sub-scanning direction. Further, in step S209, the scanner 1 is moved to the designated position D2, and in step S210, the "sub-scanning direction data reading subroutine" is called. Then, in step S211, the scanner 1 is moved to the specified position D3, and in step S212, the "sub-scanning direction data reading subroutine" is called. Further, in step 8213, the scanner 1 is moved to the specified position D4, and in step S214, the "sub-scanning direction data reading subroutine" is called, and data in each sub-scanning direction is read.

Subsequently, in step S215, a "sub-scanning direction detection subroutine" is called, and the document size in the sub-scanning direction is replaced with a flag. In step S216, flag B, which means that the number of detection points of the document size in the sub-scanning direction is zero, is set to "
0", and when flag B is "0", in step S217 flag C is set to "0" and flag D is set to "1" indicating that it is impossible to detect the document size in the sub-scanning direction. and break out of this routine. Further, when the number of detection points for the document size in the sub-scanning direction exists in step 8216, the r size determination subroutine is called in step S218 to determine whether the document size matches the predetermined document size in the table storing standardized document sizes. Check whether In step S219, it is determined whether the result of the check is a combination error, and if it is a combination error, flag C is set to "1" in step S220 to memorize that the document size cannot be defined.
Then, the flag D is set to "1" and this routine is exited. In step S221, the flag C is set to "0" and the flag D is set to "0" to remember that the document size has been defined, and in step S222, the flag E is set to "0" to remember that the document size is the standard size. 0" and exit this routine.

Next, a flowchart of "r Main Scanning Direction Detection Routine" will be explained.

In this routine, the designated position R in the main scanning direction of forward scanning is
It is determined whether the image data of 1, R2, and R3 is "white" data, and the position of the "white" data is stored in a flag.

In step S231, a counter A is set to the number n of times the width of the substantially L-shaped area is detected a plurality of times.

The number of detections n is calculated by dividing the width of the oval-shaped area in the sub-scanning direction by the scanner movement distance d in the sub-scanning direction. In step 8232, the read data is written to the line memory 830, and in step 8233, the scanner 1 determines whether there is white data at the specified position R1 calculated from the paper standard. If there is white data at the specified position R1, step 8
In step 234, flag A is set to "1", and in step 823
In Step 5, it is determined whether there is white data at the designated position R2, and when there is white data in the designated position R2, the flag A is set to "2" in Step 3236, and in Step 8237 it is determined whether there is white data in the designated position R3. However, when there is white data at the designated position R3, the flag A is set to "3" in step 8238, and this routine is exited.

Step 8233, Step 8235, Step 823
When it is determined in step S239 that there is no white data between the designated distance R1 and the designated distance R3, the counter A is set to "0" in step S239.
”, and when the counter A is not “0”, in step S241, the scanner 1 is moved by the scanner movement distance d in the sub-scanning direction, which is the scanning interval in the main scanning direction,
In step S242, the value of counter A is decremented by "1", and the routine from step 8232 is repeatedly executed.

Further, if it is determined that the counter A is not "0" in step S239. and sets flag A to "0" in step S240.
and exit this routine.

Next, a flowchart of the sub-scanning direction data reading subroutine will be described.

In this routine, the specified position D in the sub-scanning direction of the forward scan is
i, D2, . The image data of D3 and D4 is stored in the memory M.

The read data is written to the line memory 830 in step S251, and the line memory 83 written in step S252
The data of the width of the abbreviated character area in the main scanning direction from 0 is written into the memory M. Then, in step 8253, the specified position in the sub-scanning direction is determined.

When the designated position D1 in the sub-scanning direction is reached, the data written in the memory M is stored in the designated area of the designated position D1 of the buffer memory in step S254, and this routine is exited. When the designated position D2 in the sub-scanning direction is reached, the data written in the memory M is stored in the designated area of the designated position D2 of the buffer memory in step S255, and this routine is exited. Similarly,
When the designated positions D3 and D4 in the sub-scanning direction, step 82
56. In step S257, the designated position D of the buffer memory is
3. Store the data written in memory M in the designated area D4 and exit from this routine.

Next, a flowchart of the "sub-scanning direction detection subroutine" will be explained.

In this routine, specified positions DI, D2,
It is determined whether the image data of D3 and D4 is "white" data, and the position of the "white" data is stored in a flag.

In step 8261, data at a predetermined designated position D4 is read from the buffer memory, and in step 8262, data at the designated position D4 is read out from the buffer memory.
4 is white data, and if it is white data, set flag B to "4" in step 8263, and move to specified position D.
4 is not white data, the data at a predetermined designated position D3 is read from the buffer memory in step 8264, and it is determined in step S265 whether the designated position D3 is white data, and when it is white data, flag B is set to " 3
” and exit this routine.

Further, if the designated position D3 is not white data, step 8
At step 267, the data at a predetermined designated position D2 is read from the buffer memory, and at step 8268 it is determined whether the designated position D2 is white data, and if it is white data, the data at step 8269 is read.
Set flag B to "2" and exit from this routine. Similarly, when the designated position D2 is not white data, the data of a predetermined designated position D1 is read from the buffer memory in step S270, and it is determined in step S271 whether the designated position D1 is white data, and if it is white data, step S2
At step 72, flag B is set to "1" and the routine is exited. When it is determined in step S271 that the designated position D1 is not white data, in step 8273 flag B, which means that the sub-scanning direction could not be detected, is set to "0", and this routine is exited.

Next, a flowchart of "r size determination subroutine" will be explained.

In this routine, it is determined whether the detected document size is the standard size or not, and if it is not the standard size from the detected positions in the main scanning direction and the sub-scanning direction, a combination error output is set.

The relationship between the flag A and the flag B in FIG. 27 in which the standardized original size is stored in step S281 and the standardized original size is checked to see if the currently detected original size matches the table, and the corresponding one is checked. If so, exit this routine immediately.

If there is no matching item, a combination error is set in step S282 and the routine exits.

The image reading device used in the copying machine according to the embodiment of the present invention is disposed on the second side of a document table 9 made of a transparent member on which a document such as a plain paper document P or a transparent document Pot{P is placed. ,
The surface corresponding to the upper surface of the document table 9 is connected to the image sensor 13.
A white area and a black area that can be read by a photoelectric conversion element consisting of a photoelectric transducer, etc., and one predetermined corner of the document table 9 is set as a document reference position S, and the document is transmitted through the document table 9 to the document reference position S,
An area that can be read as a black area by a photoelectric conversion element is read as black by a document pressing cover 8 that presses down the document formed parallel to the main scanning direction 8CY and sub-scanning direction 8Cx, and the photoelectric conversion element of the document pressing cover 8. Main scanning direction 8 starting from the document reference position S of the document table 9 in the possible area
An optical detection means such as a scanner 1 that detects reflected light at a position corresponding to the standard length of paper in the CY and sub-scanning directions 8CX, and a document reference position S of the document table 9 on which the optical detection means places the document. When it is determined that there is no original placed on the
The apparatus is equipped with a reading prohibition control means consisting of a ``reading/printing routine'' and a ``original size detection routine'' that are called by the main program to prohibit entry into the reading operation of the original.

Therefore, when a document is placed on the document table 9, an area readable as black by the photoelectric conversion element constituted by the image sensor 13 in the main scanning direction 8CY starting from the document reference position S of the document table 9 By detecting the reflected light at a position corresponding to the standard paper length in the sub-scanning direction 8CX using the "main-scanning direction detection routine" and the "sub-scanning direction detection subroutine", it is possible to determine whether a given document is of the standard paper size. It is possible to detect the predetermined document size without calculation. Therefore, by detecting the existence of a document size of a predetermined standard length while executing the ``main scanning direction detection routine'' and the ``subroutine detecting sub-scanning direction'', it is possible to detect the document size of the standard length that is the most common in normal use. The detection is
The standard document size can be detected simply by detecting the presence or absence of a document at a predetermined position on the document table 9 without any calculation, and the time required to calculate the document size by calculation can be saved.

Further, when the optical detection means determines that the original is not placed at the original reference position S of the original platen 9 on which the original is placed,
Since entering the original reading operation is prohibited by the reading prohibition control means consisting of the ``reading/printing routine'' and the ``r original size detection routine'' called by the main program, when the original is not placed at the original reference position S. , document reference position S of document table 9, main scanning direction 8CY, and sub-scanning direction 8CX
When the original is not placed properly on the original platen 9, the image reading device does not start operating when no original is placed on the original platen 9. Therefore, it is possible to prevent the time necessary for image reading, and in the case of the embodiment used in a copying machine, to prevent unnecessary paper from becoming a cause of miscopy, thereby eliminating wasted time and wasted resources. can.

Furthermore, in this embodiment, in the "original size detection routine", if the detection in the main scanning direction is not performed normally, the sub-scanning accompanying the subsequent size detection is not performed, and the unnecessary waste associated with the scanner's original size detection is avoided. Pre-scanning can be prevented.

The abbreviated area 8C consisting of the main scanning direction 8CY and the sub-scanning direction 8CX for detecting the document size of the image reading device of the above embodiment is arranged in advance along the side of the document, and its width is also known. Therefore, even if the original is a transparent original such as OPH paper, the abbreviated area 8C that can be read as black by the detection means can be electrically processed as white, and at the same time, the edge of the original can be processed as white. Noise near edges can be removed. Therefore, the entire surface of the document pressing cover 8 on the document side can be set with respect to the document without considering the spectral distribution.

Further, the image reading device of the above embodiment has an abbreviation-shaped area 8C.
The detection means for detecting the original disposed between the upper surface of the original platen 8 made of a transparent member and the abbreviated area 8C and the upper surface of the original platen 8 made of a transparent member are
Since it is used to judge the original placed between It can be handled using only electrical processing without adding any physical components.

In the image reading device of the above embodiment, the arrangement of the abbreviation-shaped area 8C with respect to the document table 9 made of a transparent member is parallel to the main scanning direction 8CY and the sub-scanning direction 8CX. The length and/or width of the region 8C can be minimized in the main scanning direction 8CY and the sub-scanning direction 8CX, and it is easy to determine the erasure processing region of the abbreviated region 8C.

Further, in the image reading device of the above embodiment, the arrangement of the abbreviation-shaped area 8C with respect to the document platen 9 made of a transparent member is parallel to the main scanning direction 8CY and the sub-scanning direction 8CX, and the end portion of the transparent member The width from the top is approximately 5 mm, and the margin space of a normal manuscript is used as the reading space, so it matches the way margins are taken in general manuscripts.For example, if you use OHP paper as a manuscript. Even if the abbreviation-shaped area 8C is electrically processed to be white, the contents of the document will not be affected. In the above embodiment, the width from the edge of the transparent member is about 51 mm, but given the way margins are usually taken for manuscripts, if the width is set to 101 WIT1 or less, information on the manuscript will be lost. Never.

By the way, the image reading device used in the copying machine of the above embodiment is disposed above the document table 9 made of a transparent member on which documents such as the plain paper document P and the transparent document POIIP are placed. The surface corresponding to the upper surface is a white region and a black region that can be read by a photoelectric conversion element consisting of an image sensor 13, and one predetermined corner of the document table 9 is designated as a document reference position S.
A document pressing cover that presses down the document is formed at the document reference position S so that an area that passes through the document table 9 and can be read as a black area by a photoelectric conversion element is parallel to the main scanning direction 8CY and the sub-scanning direction 8CX. 8. However, when implementing the present invention, when viewed from the scanner 1 side of the document platen 9 made of a transparent member, there are photoelectric conversion elements on the document pressing cover 8 side that are readable as black in the main scanning direction 8CY and sub-scanning direction 8CX. Since it is sufficient that the area exists, the abbreviation-shaped area 8C of the above embodiment is independently set in the main scanning direction 8C.
It can be a region in the Y direction and the sub-scanning direction 8CX.

Further, in the image reading device according to the embodiment of the present invention, the surface of the document pressing cover 8 disposed on the top surface of the document table 9 on which the document is placed is white, which corresponds to the top surface of the document table 9 on which the document is placed. year,
Since the black area for document detection can be a surface surrounding the white surface, the shape of the black area of the document pressing cover can be formed without being limited to an approximately L-shape, increasing the degree of freedom in its design. It can be made higher.

The image reading device of the above embodiment transfers readable white and black colors to the original platen 8 of the original pressing cover 8 using the photoelectric conversion element.
Since the side surface can be formed as a black frame surrounding three or more sides of the white surface, the black color that can be read by the photoelectric conversion element of the document pressing cover 8 is not limited to the approximately L-shape, but can be formed into a concave shape. Alternatively, it can be shaped like a square, and can be designed so that the user is not aware of the detection function.

Further, in the image reading apparatus of the above embodiment, the detection means for detecting the document placed between the oval-shaped area and the upper surface of the transparent member is performed by preliminary scanning before the scanner 1 starts the copying operation. . However, the scanner 1 of the above embodiment
Since the detection means according to the present invention detects the presence of a document at a specified location, as shown in FIG. Can be configured.

In FIG. 28, a light emitting element 121 consisting of an LED or the like,
Reference numeral 123 irradiates the document surface placed on the upper surface of the document table 9 made of a transparent member at an incident angle θ. Further, the light receiving elements 122 and 124 such as phototransistors have an incident angle set perpendicular to the original surface, and detect the presence of the original by diffused reflection from the original rear surface.

That is, when an original is present, the light receiving elements 122 and 124 receive scattered light from the original, and when no original is present, the light receiving elements 122 and 124 are totally reflected by an oval-shaped area (not shown) at a reflection angle θ. No light enters the light receiving elements 122 and 124.

Note that the light emitting elements 121, 123 and the light receiving element 122
, 124 constitute a photocoupler.

In this type of embodiment, even if the image reading device according to the embodiment of the present invention is used in a copying machine, there is no need to perform preliminary scanning, and the document can be placed directly by opening and closing the document pressing cover 8. It is possible to make a judgment and eliminate wasted time required for preliminary scanning.

Further, the detection means shown in FIG. 28 includes light emitting elements 121,
123 and light-receiving elements 122 and 124 are optically coupled to form a so-called photocoupler, and the light generated from the light-emitting elements 121 and 123 is directly irradiated onto the document, but the synthetic resin of OHP paper etc. has a polarizing effect. Therefore, by disposing a polarizing filter between the light emitting elements 121, 123 and the light receiving elements 122, 124, the detection sensitivity of OHP paper, etc. can be increased.

In addition, by using a polarizing filter, the photoelectric conversion element can determine the difference between the presence of a document and the abbreviation-shaped area, even if they are recognized as the same color to the naked eye. The difference between the two is not uniquely determined by "white" or "black" as determined by the naked eye.

It is determined by a photoelectric conversion element that converts light into an electrical signal. Therefore, the degree of freedom in design is increased, and O
HP paper can also be easily detected.

Although the present invention has been described as an example of use in a copying machine, the present invention can be applied to any image processing device such as an image scanner or a facsimile.

In addition, as examples of detection means, we have explained an example using a scanner of a copying machine and an example using a photocoupler.
When carrying out the present invention, any means for optical detection may be used.

[Effects of the Invention] As described above, the image reading device according to claim 1 is arranged above a transparent member on which a document is placed, and a photoelectric conversion element is provided on the surface corresponding to the top surface of the transparent member on which the document is placed. A white area and a black area that can be read at the same time, one predetermined corner of the transparent member on which the original is placed is set as the original reference position, and the transparent member is transmitted through the original reference position, and a photoelectric conversion element is used as the black area. A document pressing cover that presses down the document is formed such that a readable area is parallel to the main scanning direction and the sub-scanning direction, and the document is placed in an area that can be read as black by a photoelectric conversion element of the document pressing cover. an optical detection means for detecting reflected light at a position corresponding to the standard length of the paper in the main scanning direction and the sub-scanning direction starting from the document reference position of the transparent member; and a transparent member on which the document is placed; The apparatus further includes a reading prohibition control means for prohibiting a reading operation of the original when it is determined that the original is not placed at the original reference position of the member.

Therefore, the optical detection means is located at a position corresponding to the standard length of the paper in the main scanning direction and the sub-scanning direction starting from the document reference position of the transparent member on which the document is placed, with the document reference position determined. By detecting the reflected light, the size of the original placed between the upper surface of the transparent member and the main scanning direction and sub-scanning direction formed on the original pressing cover for pressing the original can be detected as the black color. Direct detection is possible simply by detecting the states in the scanning direction and sub-scanning direction.

Furthermore, when the optical detection means determines that the document is not placed at the document reference position on the document table on which the document is placed, the reading prohibition control means prohibits the document from being read. The image is scanned when the original is not placed at the original reference position, when the original is not placed correctly in the original reference position on the original platen, in the main scanning direction and in the sub-scanning direction, or when the original is not placed on the original platen. The device never enters operation. Therefore, it is possible to prevent the time necessary for image reading and, in the case of the embodiment used in a copying machine, from causing unnecessary copies such as unnecessary paper, thereby eliminating wasted time and wasted resources. I can do it.

In the main scanning direction and sub-scanning direction for detecting the document size, the width can be arranged in advance along the sides of the document, and the width is known. For example, if the document is a transparent document such as OPH paper, Even if there is, it is easy to electrically process areas in the main scanning direction and sub-scanning direction that can be read as black by optical detection means as white, and at the same time, noise near the edges of the document can be removed. be able to.

In the image reading device according to a second aspect of the present invention, the area formed to be parallel to the main scanning direction and the sub-scanning direction and which can be read as black in the photoelectric conversion element according to the first aspect is an abbreviation-shaped area. The arrangement of the abbreviated letter-shaped area can be made parallel to the main scanning direction and the sub-scanning direction, and the length and/or width of the substantially L-shaped area can be minimized with respect to the main scanning direction and the sub-scanning direction. Furthermore, it is easy to determine the erasure processing area of the oval-shaped area.

In the image reading device according to claim 3, the approximately L-shaped area is arranged in parallel to the main scanning direction and the sub-scanning direction with respect to the transparent member according to claim 2, and the width from the end of the transparent member is The size is approximately 10 mm or less, and the margin space of a normal manuscript is used as the reading space, so by using the normal margins of a normal manuscript, even if OHP paper is used as the manuscript Even if the approximately L-shaped area is electrically processed to be white, the contents of the document will not be affected.

In the image reading device according to a fourth aspect of the invention, the areas formed to be parallel to the main scanning direction and the sub-scanning direction that can be read as black in the photoelectric conversion element of the above-mentioned aspect of the first aspect are formed in a plurality of independently formed areas in the main scanning direction and the sub-scanning direction. Therefore, the area formed parallel to the main scanning direction and the sub-scanning direction can be expressed as a pattern.

In the image reading device according to claim 5, the area formed to be parallel to the main scanning direction and the sub-scanning direction, which can be read as black with the photoelectric conversion element according to claim 1, is formed on the surface of the document pressing cover on the transparent member side. Since it is formed as a frame of a black area surrounding three or more sides of the surface of the white area, the abbreviation-shaped area of the document pressing cover is not limited to an approximately L-shape, but can be formed into a concave shape or a square shape. The configuration can be designed so that the user is not aware of the detection function.

The image reading device according to claim 6 comprises the above-mentioned claims 1 to 5.
The optical detection means for detecting the original uses a scanner included in the image reading device, so the size of the original can be detected by preliminary scanning before normal image reading scanning. This can be done only by electrical processing without increasing the number of parts.

An image reading device according to claim 7 includes the above-mentioned claims 1 to 5.
The optical detection means for detecting the original is a photocoupler that uses a photoelectric conversion element placed at a predetermined position as a light receiving element, so it is possible to detect the original size without preliminary scanning with a scanner. After placing the manuscript,
The detection operation can be performed immediately, and the processing speed can be increased.

An image reading device according to claim 8 includes the above-mentioned claims 1 to 7.
The optical detection means for detecting the original uses a polarizing filter, so even if the colors can be recognized with the naked eye as the same color, the photoelectric conversion element cannot distinguish between the presence of the original and the abbreviation-shaped area. I can do it. Furthermore, even if a transparent original is used as the original, it can be clearly distinguished due to the difference in synthetic resin material. Therefore, the degree of design freedom is increased, and
OHP paper can also be easily detected.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram illustrating the principle when the image reading device of the present invention is implemented in a copying machine, and FIG. 2 is a main part showing the overall internal horizontal structure of a copying machine according to an embodiment of the present invention. An explanatory front view, FIG. 3 is a front view of the entire copying machine according to an embodiment of the present invention,
FIG. 4 is an overall perspective view of an editor used in a copying machine according to an embodiment of the present invention, FIG. 5 is a schematic block diagram of the entire control system of a copying machine according to an embodiment of the present invention, and FIG. 6 7 is a schematic circuit diagram of an operation panel of a copying machine according to an embodiment of the present invention, FIG. 7 is a schematic circuit diagram of an editor, and FIG.
9 is a schematic circuit diagram of the reading section, FIG. 9 is a schematic circuit diagram of the printing section, and FIG. 10 is a specific circuit diagram of the unnecessary area processing section used in the embodiment of the present invention. FIG. 11 is a plan view of the document table of the copying machine according to the embodiment of the present invention, and FIG. 12 is an explanatory diagram showing the positional relationship between the document pressing cover and the document when the document of the copying machine according to the embodiment of the present invention is shifted. , FIGS. 13 to 19 are flowcharts of a copying machine according to an embodiment of the present invention, and FIGS. 20 to 24 are image reading operations when the image reading apparatus according to the embodiment of the present invention is implemented in a copying machine. FIG. 25 is an explanatory diagram showing the relationship between the unnecessary area and document size data in the above embodiment, FIG. 26 is a data chart showing the relationship between the unnecessary area and document size data in the above embodiment, and FIG. 27 is a data chart showing the relationship between flag A and flag B in the above embodiment and the standardized document size, No. 28.
The figure is an explanatory diagram of another example of the optical detection means used in the image reading device according to the embodiment of the present invention. In the figure, 1: Scanner 8: Original pressing cover 80: Oval-shaped area 8CY: Main scanning direction 8CX: Sub-scanning direction
9: Original table 13: Image sensors 121, 123: Light emitting elements 122.124: Light receiving element S: Original reference position P: Plain paper original POIIP: This is an OHP original. Note that in the drawings, the same reference numerals and symbols indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] (1) Disposed above a transparent member on which a document is placed, the surface corresponding to the top surface of the transparent member on which the document is placed is a white area and a black area that can be read by a photoelectric conversion element. , and one predetermined corner of the transparent member on which the original is placed is set as the original reference position,
a document pressing cover for pressing a document formed in the document reference position so that an area that can be read as a black area by a photoelectric conversion element through a transparent member is formed parallel to the main scanning direction and the sub-scanning direction; Detecting reflected light at a position corresponding to the standard length of the paper in the main scanning direction and the sub-scanning direction starting from the document reference position of the transparent member on which the document is placed, in an area that can be read as black by the photoelectric conversion element. an optical detection means; and a reading prohibition control means for prohibiting a document reading operation when the optical detection means determines that the document is not placed at a document reference position of a transparent member on which the document is placed. An image reading device comprising: (2) The area formed to be parallel to the main scanning direction and the sub-scanning direction that can be read as black with the photoelectric conversion element is approximately L
The image reading device according to claim 1, characterized in that the image reading device has a character-shaped area. (3) The arrangement of the substantially L-shaped area with respect to the transparent member is parallel to the main scanning direction and the sub-scanning direction, and the width of the transparent member is about 10 mm or less. The image reading device described in . (4) A claim characterized in that the area formed parallel to the main scanning direction and the sub-scanning direction that can be read as black in the photoelectric conversion element is a plurality of independently formed areas in the main scanning direction and the sub-scanning direction. The image reading device according to item 1. (5) The area formed parallel to the main scanning direction and sub-scanning direction that can be read as black by the photoelectric conversion element has three or more sides of the surface of the white area on the side of the transparent member of the document pressing cover. The image reading device according to claim 1, wherein the image reading device is formed as a frame of a surrounding black area. (6) The image reading device according to any one of claims 1 to 5, wherein the optical detection means for detecting the document uses a scanner included in the image reading device. (7) One of claims 1 to 5, wherein the optical detection means for detecting the original is a photocoupler whose light receiving element is a photoelectric conversion element disposed at a predetermined position. The image reading device described in . (8) The image reading device according to any one of claims 1 to 7, wherein the optical detection means for detecting the document includes a polarizing filter.