JP2003101691A - Image reading device and image forming device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the productivity of reading a document image in a document size mixed mode. In an image reading apparatus that reads an image while transporting a document, a reading range estimation unit estimates a reading range of the image based on a width of the document detected by the document width detection unit (step S11). The image in the read range is read by the first reading unit and converted into image data (step S13), and the converted image data is stored in the storage device by the first storage unit (step S13). This eliminates the need to detect the length of the document.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus and an image forming apparatus equipped with an automatic document feeder.

[0002]

2. Description of the Related Art In an image forming operation of a conventional image forming apparatus such as a digital copying machine, the size and orientation of a document is detected before the image of the document is read, the reading range of the image is determined, and then the image of the range is read. Running. And
The image data of the read original is stored in the storage device, the image data is read from the storage device as necessary, various processing is performed on the read image data, and the image based on the image data is formed on the transfer paper. There is.

The main reasons for detecting the size and orientation of a document in advance before reading an image are as follows.

In order to read only the image reading range corresponding to the document size, it is necessary to check whether or not there is a free space in the storage device for accumulating the image data to be read.
When storing transfer paper of different sizes in multiple paper feed trays and automatically selecting the paper feed tray according to the original size for image formation, the transfer paper of the size corresponding to the original size must be used. For example, in order to warn before scanning and to determine the scaling ratio when executing automatic transfer paper designated scaling that scales the original image according to the specified transfer paper size, the size of the original is set in advance. Since it is necessary, the above is the main reason for detecting the document size in advance before reading the image and determining the reading range of the image.

Here, in the image forming apparatus, an ADF (automatic document feeder) which automatically supplies a document to a document reading position.
There are some with. For example, Japanese Patent Application Laid-Open No. 6-035271 discloses a document in which a document is sent on a contact glass to read a document image. According to the technique disclosed in Japanese Unexamined Patent Publication No. 6-035271, the document size can be determined before reading the document image even when the document sizes and orientations are mixed.

[0006]

In a so-called general circulation type ADF which reads a document image while conveying the document, in a normal mode (non-mixed document size), a sub-scanning direction is set on the document table. A plurality of document length detection sensors arranged in the (document transport direction) detect the length of the document, and a plurality of document length sensors are provided on the document table in the main scanning direction (direction orthogonal to the document transport direction). The document width detection sensor detects the document width, which allows the document size and orientation to be determined before reading the document image.

However, in the mixed original mode, since the original length detection sensor on the original table cannot determine the length of the original, for example, a registration sensor is provided in the original conveying path to detect the leading edge of the original. The size of a document is determined by determining the length of the document based on the elapsed time from the passage of the registration sensor until the trailing edge of the document passes the registration sensor. However, in this case, since the registration sensor is close to the image reading position, the leading edge of the document reaches the reading position before the trailing edge of the document passes through the registration sensor. As a result, after the trailing edge of the document is detected by the registration sensor, the document is transported along the circulation transport path and transported again to the document reading position. Therefore, there is a problem that it takes a long time to start reading the original image and the productivity is lowered.

Here, in order to solve the above-mentioned problem, the distance of the original conveying path is increased so that the length of the maximum size original can be determined up to the original reading position, and the leading edge of the original is placed at the original reading position. It is conceivable that the trailing edge of the document passes through the registration sensor before the document arrives, but this also has a problem in that it takes a long time to start reading a document image and productivity is reduced. Further, in this case, there is a problem that the device becomes large.

Further, for example, it is conceivable to set the image reading range of all originals to that of the maximum size original without detecting the original size / orientation before image reading. The problem occurs. The problem that occurs in this case will be described with reference to FIGS. Here, FIG. 12 is a schematic diagram showing the state of the original document when being conveyed in the automatic document feeder, FIG. 13 is a schematic diagram showing the read image data, and FIG. 14 is the reading range and the original document size / direction. FIG. 15 is a schematic diagram showing reference points when they match, and FIG. 15 is a schematic diagram showing reference points when the reading range and the document size / direction do not match.

When the image reading range of all the originals A is set to that of the maximum size original, as shown in FIG. 12, in the case of the original A smaller than the maximum size, the image reading reference The point becomes the maximum size reference point 101 instead of the original reference point 100. As a result,
As shown in FIG. 3, an image in the maximum size image reading range is read with the maximum size reference point 101 as a reference. As a result, the image 103 other than the original image 102
(Hatching area in FIG. 13) is read, and an extra storage capacity is used, resulting in a problem of poor efficiency.

Further, in this case, since the storage device stores an extra image area, when the image is formed, the image is shifted so that an image other than the original image is not formed, and the alignment is performed. There is a problem that complicated processing is required.

In addition, in this case, when the read image is magnified (especially enlarged) to form the image, the image is enlarged from the document reference point 100 of the document image, but the document size and the reading range are equal to each other. If this is not done, there will be a problem in that the standard for zooming will shift and the image formed will be unsuitable. For example, as shown in FIG. 14, as shown in FIG.
Although the range 104 shown by the broken line is desired to be expanded, the range 105 shown by the broken line in FIG. 15 is expanded because the reference is displaced. For these reasons, it is difficult to set the reading range of the images of all the originals to the maximum size of the original without detecting the original size and orientation before reading the image.

An object of the present invention is to improve the productivity of reading original images in the original size mixed loading mode.

An object of the present invention is to improve the productivity of reading an original image in the mixed original size mode and to minimize the function restriction in the mixed original size mode.

[0015]

The invention according to claim 1 is
In an image reading apparatus for reading an image while conveying an original, an original width detecting unit for detecting a width of the original in a direction orthogonal to a conveying direction, and an image reading based on the width of the original detected by the original width detecting unit A reading range estimating means for estimating a range, a first reading means for reading an image of the reading range estimated by the reading range estimating means, and converting it into image data, and the image converted by the first reading means. First storage means for storing data in a storage device.

Therefore, the reading range of the image is estimated based on the width information of the document, and the image in the reading range is read and converted into image data and then stored in the storage device. There is no need to detect, and productivity in reading a document image is improved. In particular, in the mixed original mode, the operation of conveying the original only for detecting the length of the original unlike the conventional case is not required, so that the productivity in reading the original image is improved.

According to a second aspect of the invention, in the image reading apparatus according to the first aspect, the document length detecting means for detecting the length of the document in the same direction as the conveying direction, and the document length detecting means detect the document length. And a document size / orientation determining unit that determines the size and orientation of the document based on the length of the document, the first reading unit includes the document length detecting unit that determines the length of the document. Before the detection, the reading of the image in the reading range estimated by the reading range estimating means is started, and the first storage means has the image data read by the first reading means in the storage device. 1
After the document size / orientation determining unit determines the document size / orientation, the image data corresponding to the determined document size / orientation is stored in the next storage device.
The data is transferred from the secondary storage device to the secondary storage device included in the storage device and stored in the secondary storage device.

Therefore, the reading range of the image is estimated based on the width information of the document, and the image in the reading range is read and converted into image data and then stored in the storage device. There is no need to detect, and productivity in reading a document image is improved. In particular, in the mixed original mode, the operation of conveying the original only for detecting the length of the original unlike the conventional case is not required, so that the productivity in reading the original image is improved. And 1
Of the image data stored in the next storage device,
Since only the image data corresponding to the orientation, that is, the image data of the document is stored in the secondary storage device, the secondary storage device does not store an extra image unnecessary for image formation of the document. It is possible to efficiently use the secondary storage device. Further, in image formation, an image is formed on the basis of the image data in the secondary storage device, so that there is no extra image, so that the image forming process is facilitated.

According to a third aspect of the present invention, in the image reading apparatus according to the first aspect, after the document size / direction is determined by the document size / direction determination means, based on the determined document size / direction. A reading range fixing means for fixing the reading range of the image, a second reading means for reading the image of the reading range fixed by the reading range fixing means and converting it into image data, and a second reading means. Second storage means for storing the image data in the storage device, and estimates the reading range of the image by the reading range estimation means based on the width of the document detected by the document width detection means. The read image in the read range is read by the first reading unit and converted into image data, and the converted image data is stored by the first storage unit. A first reading method to be stored in the storage device, after the document size and orientation is determined by the document size and orientation determining means, the original size which is the established
The reading range of the image is fixed by the reading range fixing means based on the orientation, and the image of the fixed reading range is read by the second reading means and converted into image data,
A second reading method in which the converted image data is stored in the storage device by the second storage means is selectively switched according to the image forming mode.

Therefore, the first reading method for reading an image in the estimated document reading range even if the document size / direction is not decided according to the image forming mode, and the document reading range is decided after the document size / direction is decided. Then, the second reading method for selectively reading the image in the original reading range is selectively switched. Therefore, for example, in the mixed original mode, the original image is read by the first reading method, and the original size and orientation are set in the mixed original mode. Is not determined unless is confirmed, for example, in the automatic paper scaling mode, the second
By scanning the original image with the scanning method, it is possible to support a mode that does not function unless the original size and orientation are fixed. Therefore, the productivity of reading the original image in the mixed original size mode is improved and the original size mixed mode is also improved. It is possible to minimize the functional restrictions in.

According to a fourth aspect of the present invention, in the image reading apparatus according to the third aspect, after the document size / direction is determined by the document size / direction determining means, based on the determined document size / direction. A reading range fixing means for fixing the reading range of the image, a second reading means for reading the image of the reading range fixed by the reading range fixing means and converting it into image data, and a second reading means. Second storage means for storing the image data in the storage device, wherein the size and orientation of the document are determined based on the length of the document detected by the document length detection means. The reading of the image in the reading range, which is determined by the determining means and before the original length detecting means detects the length of the original, is read by the reading range estimating means. Initiated by reading means, the image data read by said first reading means, is stored into the primary storage device by the first memory means,
After the document size / orientation determining unit determines the document size / orientation, the first storage unit stores the image data corresponding to the determined document size / orientation in the secondary storage from the primary storage device. A third reading method in which the image is transferred to a device and stored in the secondary storage device, and after the document size / direction is determined by the document size / direction determining means, an image is displayed based on the determined document size / direction. The reading range is fixed by the reading range fixing means, the image of the fixed reading range is read by the second reading means and converted into image data, and the converted image data is stored by the second storage means. The second reading method stored in the apparatus is selectively switched according to the image forming mode.

Therefore, the third reading method for reading an image in the estimated original reading range even if the original size / direction is not decided according to the image forming mode, and the original reading range is decided after the original size / direction is decided. Then, the second reading method for selectively reading the image in the original reading range is selectively switched. Therefore, for example, in the mixed original mode, the original image is read by the first reading method, and the original size and orientation are different in the mixed original mode. In the mode that does not work if not confirmed, for example, in the automatic paper designation scaling mode, by reading the document image by the second reading method, it is possible to correspond to the mode that does not function unless the document size and orientation are confirmed. In the mixed size document mode, the productivity of reading original images is improved, and in the mixed document size mode, It is possible to suppress the ability to limit to a minimum.

An image forming apparatus according to a fifth aspect of the present invention includes the image reading apparatus according to any one of the first to fourth aspects, and a recording medium is recorded on a recording medium based on image data of an original read by the image reading apparatus. To form an image.

Therefore, productivity in image formation is improved.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIGS. This embodiment shows an application example to a digital copying machine as an image forming apparatus. In the present embodiment, the size of the original document to be image-read is so-called standard size A3, A4, A5, B.
4, B5 apply.

FIG. 1 is a vertical sectional front view showing the overall structure of the digital copying machine. The digital copying machine 1 includes a scanner section 2 as an image reading apparatus, and a printer section for forming an image on a transfer sheet B which is a recording medium by an electrophotographic method based on image data of an original A read by the scanner section 2. 3 and 3.

The scanner unit 2 includes a first contact glass 4, a second contact glass 5, an ADF (automatic document feeder) 6, and an optical scanning system 7 constituting first and second reading means.
Etc.

The ADF 6 is a device for automatically conveying the original A, and includes an original table 8 on which the original A is placed, a paper ejection tray 9 for ejecting the original A that has been read, and a paper ejected from the original table 8. Transport path 10a and transport path 1 communicated with the tray 9
0a is a circulation conveyance path 10b that branches from the downstream side to the conveyance path 10a upstream side, and the conveyance path for the document A is the conveyance path 10a.
Switching blade 11 for switching between the side and the circulating conveyance path 10b side,
The document A is composed of conveyance rollers 12a, 12b and the like. Here, a position facing the first contact glass 4 in the transport path 10a is a document reading position P. A registration sensor 13 constituting a document length detecting unit is provided on the upstream side of the document reading position P in the transport path 10a in the document transport direction. The distance from the registration sensor 13 to the document reading position P is set to be considerably shorter than the length of the document A having the minimum length. As a result, the device can be downsized.

Then, when the print key on the operation unit, which will be described later, is pressed, the bundle of originals A stacked on the original table 8 with the image surface facing upward is conveyed from the uppermost original A to the conveying roller 1.
The sheets 2a and 12b are conveyed along the conveying path 10a, and pass the registration sensor 13 and the document reading position P.
After that, when the switching blade 11 is on the conveyance path 10a side, the document A is conveyed toward the paper discharge tray 9, and when the switching blade 11 is on the circulation conveyance path 10b side, it is conveyed on the circulation conveyance path 10b. It is transported to the upstream side of the transport path 10 a, is transported again through the transport path 10 a, and is transported toward the registration sensor 13.

Further, on the upstream side of the registration sensor 13 in the conveying path 10a in the original conveying direction, the original width detecting sensors S1 and S2 constituting the original width detecting means are arranged in parallel along the direction orthogonal to the original conveying direction. It is set up. Further, on the document table 8, document length detection sensors S3 and S4 are arranged in parallel along the document conveyance direction. These document width detection sensors S1 and S2, document length detection sensors S3 and S4
Turns on when the document A is detected and outputs a detection signal.

Here, the arrangement positions of the document width detection sensors S1 and S2 and the document length detection sensors S3 and S4 will be described in detail with reference to FIGS. FIG. 2 shows the positional relationship between the original A set on the original table 8 and the original length detecting sensors S3 and S4, and the positional relationship between the original A conveyed on the conveying path 10a and the original width detecting sensors S1 and S2. FIG. 3 is a plan view virtually showing the same. FIG. 3 shows original width detection sensors S1 and S2 and original length detection sensor S3 depending on the size and orientation of the original A.
It is explanatory drawing which shows the original detection state (ON / OFF state) of S4.

As shown in FIGS. 2 and 3, in the document width detection sensor S1, the size and orientation (direction that is the same as the paper transport direction) of the transported document A are A3 portrait, A4 landscape, B4.
The document width detection sensor S2 is arranged at a position for detecting only the document A in the vertical and B5 horizontal directions, and the document width detection sensor S2 is arranged at a position for detecting only the document A in the size and direction of the conveyed document A of A3 vertical and A4 horizontal. The document length detection sensor S3 has a size / orientation of A3 portrait, B4 portrait, among document A placed on the document table 8.
The document length detection sensor S4 is arranged at a position for detecting only the A4 portrait document A, and the document length detection sensor S4 detects only the document A having the A3 portrait size and the B4 portrait size among the documents A placed on the document table 8. It is located at the position.

Further, as shown in FIG. 1, a document set detecting sensor 14 for detecting that the document A is set on the document table 8 is provided on the document table 8.

The optical scanning system 7 reads the image of the original A conveyed to the original reading position P or the original A placed on the second contact glass 5. As shown in FIG. 1, the optical scanning system 7 includes an exposure lamp 15, a first mirror 16, second and third mirrors 17 and 18, and an imaging lens 19.
And an image sensor such as a line type CCD 20. Exposure lamp 15 and first mirror 16
Is mounted on the first carriage (not shown),
The third mirrors 17 and 18 are mounted on a second carriage (not shown). These first and second carriages are driven by a scanner drive motor (not shown). The original image is read and scanned by the optical scanning system 7 to form a reduced image on the CCD 20, and is read so as to be an electric signal through photoelectric conversion processing.

The printer section 3 is composed of a photoconductor 21, a laser unit 22, a developing device 23, a transfer device 24, a fixing device 25 and the like. The surface of the photoconductor 21 is uniformly charged by a charger (not shown), and the image read by the scanner unit 2 on the surface of the photoconductor 21 is the laser unit 2.
2 is written to form an electrostatic latent image. The electrostatic latent image is visualized as a toner image by supplying toner from the developing device 23, and the visualized toner image is transferred from the paper feeding cassette 26 by the function of the transfer device 24. It is transferred onto the paper B. The transfer paper B on which the toner image has been transferred is subjected to a fixing process by the fixing device 25, and the discharge tray 27
Is ejected.

Further, the digital copying machine 1 is provided with an operation section for inputting various information. FIG. 4 is a plan view showing the operation unit. The operation unit 28 is provided in the digital copying machine 1 at a location such as the front portion of the scanner unit 2 which is easy to operate. The operation unit 28 includes a display device 29 such as an LCD (Liquid Crystal Display) having a touch panel function, a print key 30 for starting an image forming operation, and a clear key for forcibly stopping the image forming operation. A / stop key 31, a numeric keypad group 32 for inputting the number of values, a mode clear key 33 for releasing the set operation mode, and the like are provided. "You can copy" and "Please wait" are displayed on the display device 29.
A message area 34 for displaying a message such as, a copy number display area 35 for displaying the set number of sheets, and the like are provided. Then, on the display device 29, an automatic paper selection key 36 for designating a process for automatically selecting the transfer paper B, a normal magnification key 37 for setting the magnification to the same size, and a scaling for setting the enlargement / reduction magnification. Various function keys such as a key 38 and a mixed original document key 39 for setting the mixed original mode are displayed.

Next, each section of the digital copying machine 1 will be functionally described with reference to FIG. FIG. 5 is a block diagram functionally showing each unit included in the digital copying machine 1. The digital copying machine 1 has a main control unit 40 that centrally controls the driving of each unit of the digital copying machine 1. The main control unit 40 includes an image processing unit 4 which is a circuit for performing various kinds of image processing on image data read by the CCD 20.
1. Image memory unit 4 for storing processed image data
2, an operation unit 28, a mechanism control unit 43 for driving and controlling mechanical devices such as various motors (not shown) related to feeding / conveying / discharging the document A and the transfer sheet B, and an I / O port. Four
4 through the registration sensor 13 and the document width detection sensor S
1, S2, document length detection sensors S3, S4, document set detection sensor 14 and the like are connected.

The main controller 40, as shown in FIG.
A CPU (Central Processing Unit) that centrally controls each unit
nit) 45, and the CPU 45 has a ROM (Read Only Memory) 46 which is a read-only memory for storing data such as a control program in advance, and various data which can be rewritably stored as a work area of the CPU 45. A functioning RAM (Random Access Memory) 47 and a timer unit 48 for measuring time are connected by a bus 49,
It constitutes a microcomputer. Further bus 49
An HDD 50 in which a control program and the like are stored and a CD-ROM drive 52 that reads a CD (Compact Disc) -ROM 51 that is a recording medium are connected to the HDD.

The ROM 46 has A3, A4, A5, B
Stored is fixed size information in which the sizes in the vertical and horizontal directions such as 4, B5 and the like are determined. Furthermore, ROM4
In FIG. 6, the elapsed time required from the leading edge of the document A transported on the transport path 10a passing through the registration sensor 13 to the trailing edge of the document A passing through the registration sensor 13 is the document size / direction (for example, A3). Vertical, A4 horizontal, B4 vertical, B5
It is stored for each of horizontal, A4 vertical, A5 horizontal, etc.).

A predetermined control program is stored in the CD-ROM 51 shown in FIG. CPU45 is a CD
-CD control program stored in ROM51-
It is read by the ROM drive 52 and installed in the HDD 50. As a result, the main control unit 40 is brought into a state in which it is possible to perform various kinds of processing described later.

The storage medium is a CD-ROM 5
1, various types of media such as various optical discs such as DVD, various magneto-optical discs, various magnetic discs such as floppy (registered trademark) discs, and semiconductor memories can be used. Also, download the program from a network such as the Internet and
You may make it install in 50. Note that the program may be one that operates on a predetermined OS (Operating System), in which case some execution of various processes described below may be performed by the OS, or a word processor software may be used. For example, it may be included as a part of a group of program files constituting a predetermined application software or OS.

FIG. 7 is a block diagram showing the basic internal structure of the image processing section 41. As shown in FIG. 7, the image processing unit 41 includes an A / D conversion unit 53 that performs digital conversion processing of an analog image signal obtained by reading an original image by the CCD 20, a shading correction processing unit 54 that performs shading correction processing, and a shading correction. An image data processing unit 55 that performs various image data processes such as MTF correction and γ correction on the processed digital image signal, and a selector unit that switches the destination of the image signal after the data processing to a scaling unit or an image memory unit 42 described later. 56, and a variable power unit 57 for enlarging / reducing the image signal according to the variable power. Here, the digital image signal sent by the selector unit 56 to the scaling unit 57 is then sent to the printer unit 3 and is used for image formation.

FIG. 8 is a block diagram showing the basic internal structure of the image memory unit 42. As shown in FIG. 8, the image memory unit 42 includes a storage device 58 and a memory controller 59.
It has and.

The storage device 58 is composed of primary and secondary storage devices 60 and 61. The primary storage device 60 is
Data can be written substantially in synchronization with the transfer rate of input image data, and data can be read at high speed when outputting image data, that is, high-speed access is possible, for example, DRAM (Dynamic Random Access Memory) Is. Further, the primary storage device 60 is configured such that the storage area is divided into a plurality of storage areas according to the size of the image data to be processed and the input / output of the image data can be simultaneously executed. Specifically, two sets of address and data lines for reading and writing are connected to the interface with the memory controller 59 so that the input and output of image data can be executed in parallel in each divided storage area. . This enables, for example, an operation of outputting (reading) an image from the second storage area while inputting (writing) an image to the divided first storage area.

The secondary storage device 61 synthesizes image data,
It is, for example, an HDD or the like that functions as a large-capacity storage device that stores data for sorting. Here, if an element capable of high-speed access is used for both the primary and secondary storage devices 60, 61,
Although data processing can be performed without distinction of 61 and control is relatively easy, the access speed to the secondary storage device 61 is not so high, but it is cheap because the elements such as DRAM that can be accessed at high speed are expensive. A large-capacity recording medium is used, and input / output data processing is performed via the primary storage device 60.

The memory controller 59 includes an input data selector 62, an image synthesizer 63, and a primary compression / expansion unit 6.
4, output data selector 65, secondary compression / decompression unit 66
Etc.

Here, an outline of the operation of the memory controller 59 will be described. [Image Data Input (Storing Image Data in Storage Device 58)] The input data selector unit 62 selects image data to be written in the primary storage device 60 from among a plurality of image data. The image data selected by the input data selector unit 62 is supplied to the image combining unit 63 and combined with the image data already stored in the storage device 58.

The image data processed by the image synthesizing unit 63 is compressed by the primary compression / expansion unit 64, and the compressed image data is written in the primary storage device 60.

The image data written in the primary storage device 60 is further compressed by the secondary compression / expansion unit 66 as required, and then written and stored in the secondary storage device 61.

[Image Data Output (Reading of Image Data from Storage Device 58)] At the time of outputting image data, the image data stored in the primary storage device 60 is read. When the image data to be output is stored in the primary storage device 60, the primary compression / decompression unit 64 decompresses the image data in the primary storage device 60 to obtain the decompressed image data or the decompressed image data. The output data selector unit 65 selects the image data after the image combination of the subsequent image data and the input image data, and the selector unit 56 of the image processing unit 41.
Output to.

The image synthesizing unit 63 synthesizes the image data of the primary storage device 60 with the input image data (has a function of adjusting the phase of the image data) and selects the output destination of the synthesized image data (output data selector). Part 65, write back to the primary storage device 60, and simultaneous output to both output destinations).

When the image data to be output is not stored in the primary storage device 60, the output target image data stored in the secondary storage device 61 is expanded by the secondary compression / expansion unit 66. After the decompressed image data is written in the primary storage device 60, the above-described image data output operation is performed.

By adopting the configuration of the image memory unit 42 as described above, input / output of a large amount of image data, storage,
The digital copying machine 1 capable of processing such as processing can be realized at a low cost and with a relatively simple configuration.

Next, the CP provided in the main controller 40
The image reading process executed by the U45 based on the control program will be described with reference to FIG. FIG. 9 is a flowchart schematically showing the image reading process. The image reading process in the normal mode of image formation (non-mixed original document, same size), mixed original document mode, mixed original document mode and automatic paper-designation variable magnification mode will be described in order.

Here, the original mixed loading mode is a mode in which image formation of a plurality of originals stacked on the original table 8 and having different sizes and orientations is sequentially executed. The automatic paper scaling mode is the transfer paper B in which the read original image data is specified.
In order to form an image on the entire surface, this is a mode in which the magnification is determined in consideration of the sizes of the original and the transfer paper and the image formation is executed. For example, the image of the A5 size original is transferred to the entire A3 size transfer paper B. 200% when forming an image on
Will be expanded.

[Normal Mode] First, when it is determined that the document A is set on the document table 8 and the print key 30 is pressed (Y in step S1), the conveyance of the document A is started (step S2).

In the following step S3, it is determined whether or not the mixed size loading mode is set. Here, since the mixed size mode is not set (N in step S3), the document size and orientation are determined (step S4). As shown in FIG. 3, the document size and orientation are determined by detecting the document length by the document length detection sensors S3 and S4 when the document A is placed on the document table 8 and by detecting the document A along the transport path 10a. It is determined by a combination with the document width detection of the document width detection sensors S1 and S2 when being conveyed. For example, the document length detection sensors S3 and S4
Is ON and both of the document width detection sensors S1 and S2 are also ON, the document size / direction is determined to be A3 portrait.

Then, the image reading range in the document size and orientation determined in step S4 is determined based on the standard size information stored in the ROM 46 (step S5).

After determining the image reading range in step S5, when it is determined that the document A has arrived at the registration sensor 13 (Y in step S6), the conveyance of the document A is temporarily stopped, and then the document is moved to the document reading position P. Then, the re-conveyance of the document A is started. When the original A is conveyed for a predetermined distance (or a predetermined time) after the original A is re-conveyed, the original A is conveyed to the original reading position. At this time, therefore, the image of the original A is read (step S7). Specifically, image reading within the image reading range determined in step S5 is executed. Then, all the read image data is transferred to and stored in the secondary storage device 61 via the primary storage device 60 (step S8).

[Original Mixed Mode] Next, the image reading process in the mixed original mode will be described. First, the image reading process of steps S1 to S2 is executed. Then, in the mixed original mode (Y in step S3) and not in the automatic paper size changing mode (N in step S9), the width of the original A among the original sizes is determined (step S10). The width of the original A is determined by the original A.
Document width detection sensor S when the document is conveyed on the conveyance path 10a
This is performed based on the detection signals of 1 and S2. Specifically, as shown in FIG. 3, when both the document width detection sensors S1 and S2 are in the ON state, the width of the document A is at least A.
When the document width detection sensor S1 is in the ON state and the document width detection sensor S2 is in the OFF state, the width of the document A is at least B4 in the vertical or B5 width, and the document width detection sensor S1. , S2 are both OFF, it is determined that the width of the document A is at least A4 vertical or A5 horizontal. Here, the function of the document width detecting means is executed.

After the width of the document A is determined in step S10, the document size / direction is estimated from the determined document width to determine the image reading range (step S1).
1). Specifically, the size / orientation of the document having the larger size among the document widths determined in step S10 is adopted. For example, when the document size / direction is determined to be A3 portrait or A4 landscape, the document size / direction is A3 portrait,
Of the A4 landscape, the A3 portrait with the larger document size is adopted. When the size / orientation of the document A is determined to be B4 portrait or B5 portrait, the document size / orientation is B4 portrait or B5A landscape, whichever is larger, B4 portrait. If you decide the document size and orientation as A4 portrait or A5 landscape,
As the document size / orientation, A4 portrait or A5 landscape, whichever has the larger document size, is adopted. Then, the image reading range for the adopted document size is determined based on the standard size information stored in the ROM 46. Here, the function of the reading range estimating means is executed.

After determining the image reading range in step S11, if it is determined that the document A has arrived at the registration sensor 13 (Y in step S12), the conveyance of the document A is temporarily stopped, and then the document is read at the document reading position P. Start re-transportation toward. When the original A is conveyed for a predetermined distance (or a predetermined time) after the original A is re-conveyed, the original A is conveyed to the original reading position. At this time, therefore, the image of the original A is read. Specifically, image reading within the image reading range determined in step S5 is executed. Then, all the read image data is transferred to and stored in the primary storage device 60 (step S13). Here, the functions of the first reading unit and the first storage unit are executed.

Then, in step S14, the document length is detected. Specifically, the time from the detection of the leading edge of the conveyed document A by the registration sensor 13 to the detection of the trailing edge of the document A by the registration sensor 13 is measured by the timer unit 48, and the elapsed time between them is Is used as the length. Here, the function of the document length detecting means is executed. Then, the measured elapsed time is stored in the ROM 4
The original size and orientation are determined by collating with the elapsed time data for each original stored in step 6 (step S1).
5). Here, the function of the document size / orientation determining means is executed.

After the document size / direction is determined in step S15, the image data corresponding to the document size / direction determined in step S15 among the image data stored in the primary storage device 60 in step S13. The data is transferred to the secondary storage device 61 and stored in the secondary storage device 61 (step S16). Here, the function of the first storage means is executed.

Here, an example of the image reading process in the mixed original document mode will be described with reference to FIGS. 9, 10 and 11. FIG. 10 is a schematic diagram showing the image data for the B4 vertical portion stored in the primary storage device 60 for the B4 vertical original, FIG.
FIG. 6 is a schematic diagram showing image data of B4 vertical portion stored in a primary storage device 60 of a B5 horizontal original. For example, step S
In 10, the document width is determined to be B4 vertical or B5 horizontal,
In the following step S11, the document size / direction is set to B4.
If the image reading range is determined assuming that the image is vertical, then in step S13, the image data for B4 vertical is read 1
The data is transferred to the next storage device 60 and stored therein.

When it is determined in step S15 that the document size and orientation is B4 portrait,
As shown in 0, all of the B4 vertical image data stored in the primary storage device 60 is transferred to and stored in the secondary storage device 61. On the contrary, if it is determined in step S15 that the document size / direction is B5 landscape,
As shown in FIG. 11, B stored in the primary storage device 60 is stored.
Of the four vertical image data, only the B5 horizontal image data is transferred to and stored in the secondary storage device 61. Here, the functions of the first reading method and the third reading method are executed by the processing described so far.

By performing such processing in the mixed original mode, it is not necessary to detect the length of the original before reading the image of the original. Therefore, it is only necessary to detect the length of the original unlike the conventional case. The operation of conveying the original document is unnecessary, and the productivity in reading the original image can be particularly improved. Then, of the image data stored in the primary storage device 60, only the image data corresponding to the document size and orientation, that is, only the image data of the document is stored in the secondary storage device 61. Does not store an extra image that is unnecessary for forming an image on the document, and thus the secondary storage device 61 can be used efficiently. Further, in image formation, since an image is formed based on the image data of the secondary storage device 61, there is no extra image, so that the image forming process can be facilitated. There is no problem even if such an image reading process is applied to the normal mode.

[Original Mixed Loading Mode and Automatic Paper Designation Magnification / Magnification Mode] Image reading processing in the original mixed loading mode and automatic paper designation scaling mode will be described. First, the image reading process of steps S1 to S2 is executed. Since the original mixed mode is set (Y in step S3) and the automatic paper size changing mode is set (Y in step S9), the original A conveyed on the conveyance path 10a reaches the registration sensor 13 ( In step S17, the document is conveyed to the circulation conveyance path 10b to start circulation of the document (step S18).

Then, in step S19, the document size and orientation are determined. Specifically, step S14
Similarly to step S15, the time from the detection of the leading edge of the conveyed document A by the registration sensor 13 to the detection of the trailing edge of the document A by the registration sensor 13 is measured by the timer unit 48, so that Substitute the elapsed time as the length. Then, the measured elapsed time is RO
The original size and orientation are determined by collating with the elapsed time data for each original stored in M46.

Thereafter, the document reading process of steps S5 to S8 is executed. The functions of the reading range determining means, the second reading means, and the second storage means are executed here.
Here, the function of the second reading method is executed by the processing described so far. Here, such an image reading process is not executed only in the mixed original document mode and the automatic paper size changing mode, but may be executed in a mode that does not function unless the original size and orientation are fixed.

As described above, in the digital copying machine 1 of the present embodiment, the processing method in the mixed original document mode, the mixed original document mode, and the automatic paper size changing mode is selectively selected according to the image forming mode. Since the mode is switched, it can also support modes that do not work unless the document size and orientation are fixed, such as the mixed document mode and automatic paper scaling mode, and improve the productivity of reading original images in the mixed document size mode. In addition, the function limitation in the mixed original size mode can be minimized.

[0072]

According to the first aspect of the present invention, in an image reading apparatus for reading an image while conveying an original, an original width detecting means for detecting the width of the original in a direction orthogonal to the conveying direction, and the original width. A reading range estimating means for estimating a reading range of an image based on the width of the document detected by the detecting means, and a first image for reading the image in the reading range estimated by the reading range estimating means and converting the image into image data. By including a reading unit and a first storage unit that stores the image data converted by the first reading unit in a storage device, the reading range of the image is estimated based on the width information of the document, Since the image in the reading range is read and converted into image data, it is stored in the storage device.
Since it is not necessary to detect the length of the document, the productivity in reading the document image can be improved. In particular, in the mixed original mode, the operation of conveying the original only for detecting the length of the original, which is required in the related art, is unnecessary, so that the productivity in reading the original image can be particularly improved.

According to the second aspect of the invention, in the image reading apparatus according to the first aspect, the document length detecting means for detecting the length of the document in the same direction as the conveying direction, and the document length detecting means. And a document size / orientation determining unit that determines the size and orientation of the document based on the detected length of the document, wherein the first reading unit includes the document length detecting unit that determines the document length. Reading of the image in the reading range estimated by the reading range estimating means is started before the detection of the depth, and the first storage means stores the image data read by the first reading means in the storage device. Stored in a primary storage device included in the device, and after the document size / direction determining means determines the document size / direction, the image data corresponding to the determined document size / direction is transferred from the primary storage device. The reading range of the image is estimated based on the width information of the original by transferring to the secondary storage device of the storage device and stored in the secondary storage device, and the image in the reading range is read and the image is read. Since the data is stored in the storage device after being converted, it is not necessary to detect the length of the document, and thus the productivity in reading the document image can be improved. In particular, in the mixed original mode, the operation of conveying the original only for detecting the length of the original, which is required in the related art, is unnecessary, so that the productivity in reading the original image can be particularly improved. Then, of the image data stored in the primary storage device, only the image data corresponding to the document size / orientation, that is, only the image data of the document is stored in the secondary storage device. There is no need to store extra images that are unnecessary for forming an image on a document, which allows the secondary storage device to be used efficiently. Further, in image formation, an image is formed on the basis of the image data in the secondary storage device, so that there is no extra image, so that the image forming process can be facilitated.

According to the third aspect of the invention, in the image reading apparatus according to the first aspect, after the document size / direction is determined by the document size / direction determining means, the determined document size / direction is changed to the determined document size / direction. A reading range determining unit that determines a reading range of the image based on the reading range, a second reading unit that reads the image of the reading range determined by the reading range determining unit and converts the image into image data, and a second reading unit Second storage means for storing the read image data in the storage device, and the reading range estimation means estimates an image reading range based on the width of the document detected by the document width detection means. An image of the estimated reading range is read by the first reading unit and converted into image data, and the converted image data is read by the first storage unit. And a first reading method in which the document size / direction is determined by the document size / direction determining means, and an image reading range is set based on the determined document size / direction. A second image read by the second reading device to convert the image of the read range confirmed by the determining device into the image data, and the converted image data is stored in the storage device by the second storage device; By selectively switching between the scanning method and the image formation mode,
The first reading method of reading an image in the estimated original reading range even if the original size / direction is not decided according to the image forming mode, and the original reading range is decided after the original size / direction is decided. Since the second reading method for reading the image in the range is selectively switched, for example, in the mixed original mode, the original image is read by the first reading method, and the original size and orientation must be determined in the mixed original mode. If the original size / direction does not work, for example, in the automatic paper size changing mode, by reading the original image by the second reading method, it is possible to correspond to the mode that does not work unless the original size / direction is fixed. It is possible to improve the productivity of reading original images and limit the functions in the mixed original size mode. It can be suppressed to a minimum.

According to the fourth aspect of the invention, in the image reading apparatus according to the third aspect, after the document size / direction is determined by the document size / direction determining means, the determined document size / direction is set. A reading range determining unit that determines a reading range of the image based on the reading range, a second reading unit that reads the image of the reading range determined by the reading range determining unit and converts the image into image data, and a second reading unit Second storage means for storing the image data thus obtained in the storage device, and based on the length of the document detected by the document length detection means, the size of the document and the direction of the document are determined based on the document size. The reading of the image within the reading range that is estimated by the reading range estimating means before the original length detecting means detects the length of the original document. The image data read by the first reading unit is read by the first storage unit and stored in the primary storage unit by the first reading unit, and the document size / direction determining unit sets the document size / direction. After the determination is made, the image data corresponding to the determined document size and orientation is transferred from the primary storage device to the secondary storage device by the first storage means and stored in the secondary storage device. After the third reading method and the document size and orientation are determined by the document size and orientation determining means, the image reading range is determined by the reading range determining means based on the determined document size and orientation. The image of the confirmed reading range is read by the second reading unit and converted into image data, and the converted image data is read by the second storage unit. By selectively switching between the second reading method in which the image is stored in the storage device and the second reading method according to the image forming mode, the estimated reading range of the original reading range can be set even if the original size and orientation are not fixed according to the image forming mode. Since the third reading method for reading the image and the second reading method for reading the image in the original reading range after the original reading size is fixed after the original size / direction is fixed, for example, in the mixed original loading mode. Reads the original image by the first reading method, and does not work in the mixed original document mode and the original size and orientation are not fixed. For example, in the automatic paper size changing mode, the original image is read by the second reading method. By doing so, it is possible to support a mode that does not work unless the document size and orientation are fixed. It is possible to improve the productivity of reading a document image and to suppress the function limitation in the document size mixed loading mode to the minimum.

According to the invention of an image forming apparatus described in claim 5, the image reading apparatus according to any one of claims 1 to 4 is provided, and recording is performed based on image data of a document read by the image reading apparatus. By forming an image on the medium, productivity in image formation can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing the overall structure of a digital copying machine according to an embodiment of the present invention.

FIG. 2 is a plan view that virtually and simultaneously shows a positional relationship between a document set on a document table and a document length detection sensor, and a positional relationship between a document conveyed along a conveyance path and a document width detection sensor. is there.

FIG. 3 is a document width detection sensor according to the size and orientation of the document,
FIG. 6 is an explanatory diagram showing a document detection state (ON / OFF state) of a document length detection sensor.

FIG. 4 is a plan view showing an operation unit.

FIG. 5 is a block diagram functionally showing each unit of the digital copying machine.

FIG. 6 is a block diagram showing a basic internal configuration of a main control unit.

FIG. 7 is a block diagram showing a basic internal configuration of an image processing unit.

FIG. 8 is a block diagram showing a basic internal configuration of an image memory unit.

FIG. 9 is a flowchart schematically showing an image reading process.

FIG. 10: B4 stored in the primary storage device for B4 portrait originals
It is a schematic diagram which shows the image data of a vertical part.

FIG. 11: B5 stored in the primary storage device for B5 landscape originals
It is a schematic diagram which shows the image data of a vertical part.

FIG. 12 is a schematic view showing a state of a document when it is conveyed in a conventional automatic document feeder.

FIG. 13 is a schematic diagram showing read image data.

FIG. 14 is a schematic diagram showing reference points when the reading range and the document size / direction match.

FIG. 15 is a schematic diagram showing reference points when the reading range and the document size / direction do not match.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 image forming apparatus (digital copying machine) 2 image reading apparatus (scanner section) 7 first reading means, second reading means (optical scanning system) 13 document length detecting means (registration sensor) 58 storage device 60 primary storage device 61 Secondary Storage Device A Document B Recording Medium (Transfer Paper) S1, S2 Document Width Detection Means (Document Width Detection Sensor)

Claims (5)

[Claims] 1. An image reading apparatus for reading an image while conveying a document, comprising: a document width detecting means for detecting a width of the document in a direction orthogonal to a conveying direction; and a width of the document detected by the document width detecting means. A reading range estimating means for estimating a reading range of an image based on the reading range; a first reading means for reading an image in the reading range estimated by the reading range estimating means and converting it into image data; and a first reading means. An image reading apparatus comprising: a first storage unit that stores the converted image data in a storage device. 2. A document length detecting means for detecting the length of a document in the same direction as the conveying direction, and the size and orientation of the document based on the length of the document detected by the document length detecting means. A reading range estimated by the reading range estimating means before the original length detecting means detects the length of the original. The first storage means stores the image data read by the first reading means in a primary storage device included in the storage device, and the document size / orientation determining means After the document size / direction is determined, the image data corresponding to the determined document size / direction is transferred from the primary storage device to a secondary storage device included in the storage device to transfer the image data to the secondary storage device. In The image reading device according to claim 1, wherein the image reading device is stored. 3. A reading range determining means for determining an image reading range based on the determined document size / orientation after the document size / orientation determining means has been determined, and the reading range. Second reading means for reading an image in the reading range fixed by the fixing means and converting it into image data; and second storage means for storing the image data converted by the second reading means in the storage device, The reading range estimating means estimates the reading range of the image based on the width of the document detected by the document width detecting means, and the image of the estimated reading range is read by the first reading means. A first reading method for converting the image data into image data and storing the converted image data in the storage device by the first storage means; After the document size and orientation is determined by the determining means, and confirm by the reading range determining means the reading range of the image based on the determined original size and orientation, the determined the reading range the image second
A second reading method in which the image is read by a reading unit and converted into image data, and the converted image data is stored in the storage device by the second storage unit is selectively switched according to an image forming mode. The image reading apparatus according to claim 1. 4. A reading range determining means for determining an image reading range based on the determined document size / direction after the document size / direction is determined by the document size / direction determining means, and the reading range. Second reading means for reading the image in the reading range fixed by the fixing means and converting it into image data; and second storage means for storing the image data converted by the second reading means in the storage device, The document size and orientation of the document based on the length of the document detected by the document length detection means.
The first reading unit starts reading an image of the reading range, which is determined by the direction determining unit and before the document length detecting unit detects the length of the document, and the reading range image is estimated by the reading range estimating unit. (1) The image data read by the reading unit is stored in the primary storage unit by the first storage unit, and after the document size / direction determination unit determines the document size / direction, the determined document size is determined. A third reading method in which the image data corresponding to the orientation is transferred from the primary storage device to the secondary storage device by the first storage means and stored in the secondary storage device; After the document size and orientation are confirmed by the orientation determining means, the image reading range is determined by the reading range determining means based on the determined document size and orientation. The image of the read range determined and fixed
A second reading method in which the reading unit reads and converts the image data, and the converted image data is stored in the storage device by the second storage unit is selectively switched according to an image forming mode. The image reading apparatus according to claim 2. 5. An image forming apparatus comprising the image reading device according to claim 1, and forming an image on a recording medium based on image data of a document read by the image reading device.