JP2003264671A - Image reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform original conveyance control to realize an optimal read performance even in the case of an original mixture mode designating an auto- magnification during reading. <P>SOLUTION: A CCD sensor part 16 and a CIS sensor part 20 successively output image read information. An image processing part 102 applies the write/ read of image information to an image memory part 103. A CPU 104 performs setting or control of the image processing part 102 and the read/write of image information. A read mode is set and read operation start is instructed by an operation part 110. On a display part 111, mode setting is performed. A motor driver part 113 drives a motor 114 and a motor 115 for driving the conveyer rollers of first and second original conveyance control parts. The magnification or resolution conversion of a read conveying direction (sub-scanning direction) is realized by changing the driving speed of the motors while fixing the read speed of a CCD or a CIS. <P>COPYRIGHT: (C)2003,JPO

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 more particularly, to an image reading apparatus capable of simultaneous double-sided reading by one document conveyance.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram of an image reading apparatus having a conventional double-sided simultaneous reading mechanism, and mainly shows the layout of the reading positions on both sides of a document and the layout of a conveyance path. The image reading apparatus having such a configuration has a first reading sensor (CCD) 301 for reading the front surface (first surface) and a back surface (second surface).
A second reading sensor (contact image sensor) 302 for reading the surface) is provided, and while the original placed on the original tray (not shown) is fed to the discharge side by the rollers of the same drive source, the first The original reading sensor 301 and the second original reading sensor 302 serve as a mechanism for sequentially reading both surfaces in one conveyance. Note that reference numerals 303 and 304 indicate reference white plates.

In the image reading apparatus, there is known an original mixed loading mode in which originals of different sizes are placed on the original tray and read. Further, there is also known an automatic scaling function that detects the size of a document on a document tray so that it fits within a specified size, and automatically scales and reads. If the original mixed mode and automatic scaling are set at the same time, the original 1
For each sheet, the reading speed is set to a speed adapted to the automatic zooming and reading is performed.

[0004]

However, in double-sided simultaneous reading as described above, if automatic scaling is attempted in the mixed loading mode, the first and second original document transportation drive sources and the transportation speed are the same, and therefore continuous scanning is performed. When the two originals have different sizes, the conveyance speeds of the previous original and the next original are different, and the next original cannot be read by the first reading unit until the previous original passes through the second reading unit. There is.

That is, the next original is kept waiting before the first reading unit. Therefore, there is a problem that the manuscript space is increased, resulting in a decrease in performance.

The present invention has been made in view of the above problems, and an object thereof is to realize optimum reading performance even in a mixed original mode in which automatic scaling is designated at the time of reading. An object of the present invention is to provide an image reading device capable of controlling document conveyance.

[0007]

In order to achieve such an object, the present invention provides a document size determining means for determining a document size before reading a document.
A first original reading means for reading the first side of the original by non-stop scanning, and a second side of the original for non-stop scanning,
Second original reading means located downstream of the first original reading means; first conveying means for conveying an original in order to perform flow reading in the first original reading means;
Second conveying means for conveying an original in order to scan the original in the original reading means, and automatic magnification setting means for automatically setting the original magnification so that the original size falls within a predetermined size when the original is read. And a conveyance control means for changing the speeds of the first conveyance means and the second conveyance means based on the magnification set by the automatic magnification setting means, and an original in which a plurality of originals of different sizes are mixed. A document mixed loading mode setting means for setting a document mixed loading mode to be read, wherein the document mixed loading mode is set by the document mixed loading mode setting means, and the automatic scaling is designated by the automatic scaling setting means; It is characterized in that the transport speeds of the first transport means and the second transport means are independently controlled.

The invention described in claim 2 is the same as claim 1.
In the invention described in (1), the mixed original document mode is a double-sided reading mode.

The invention described in claim 3 is the same as claim 1
In the invention described in (1), the first conveying means conveys the first surface of the front original and the first original reading means reads it, and then the second conveying means conveys the second surface of the front original. Then, when the trailing edge of the document passes through the first transporting device during reading by the second document scanning device, the transport speed of the first transporting device is arbitrarily changed according to the size of the next document. It is characterized in that the first side of the next original is read by accelerating or decelerating to the speed.

According to the present invention, with such a structure, even in the case of the original mixed loading mode in which the automatic scaling is designated at the time of simultaneous double-sided reading, the first surface of the previous original is conveyed by the first conveying means while the first original is conveyed. After the second document is read by the document reading unit, the second surface is conveyed by the second conveying unit, and when the rear end of the document leaves the first conveying unit during the reading by the second document reading unit, By scanning the first side of the next original by accelerating or decelerating the conveying speed of the conveying means to an arbitrary variable speed that matches the size of the next original, it is possible to shorten the distance between the originals and improve the reading performance. Becomes

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining an embodiment of the image reading apparatus of the present invention. The image reading apparatus according to the present exemplary embodiment includes a reader unit including a document feeding apparatus 1 and a document reading apparatus 19. First, the configurations of the document feeding device 1 and the document reading device 19 in the reader section will be described below.

The contact type image sensor unit 20 as the first original reading unit and the original are read while moving relatively, and the exposure unit 13 in the original reading device as the second original reading unit and the original are relatively moved. The information on the original is read while moving it manually. The contact image sensor unit 20 is composed of an LED, which is a light source (not shown), a lens, and a contact image sensor.

The original 3 is set on the original tray 2.
The document feeding roller 4 is paired with the separation pad 5,
The originals 3 are fed one by one from the uppermost original of the stacked originals by the original feeding roller 4 and the separating pad 5. The fed document 3 has a pair of intermediate rollers 6
Is further fed into the apparatus by the large roller 8 and the first driven roller 9
Then, the second driven roller 10 conveys the large roller 8 around the large roller 8.

The original conveyed by the large roller 8 and the second driven roller 10 is a flow-read original glass 12 and the original guide plate 1.
7 through the jump table 18 and is again conveyed by the large roller 8 and the third driven roller 11. The document guide plate 17 is provided between the original reading glass 12 and the document guide plate 17.
The original 3 is conveyed by the above member while being in contact with the original reading original glass 12. The above rollers 8 to 11 are driven by a motor 114, which is a stepping motor, and this serves as a first document transporting unit.

Before the original 3 is conveyed, the first original reading section (CCD sensor section) 16 and the second original reading section (contact image sensor section) 20 perform shading. First
The document reading unit 16 reads the reference white plate 22 and
The document reading section 20 reads the reference white plate 21 to obtain an appropriate white level.

When the original 3 passes over the flow-read original glass 12, the exposure unit 13 causes the original 3 to flow-read original glass 12.
The surface in contact with is exposed. The exposure unit 13 transmits the document image information reflected from the document 3 by being exposed to the mirror unit 14. The transmitted document image information passes through the lens 15 and is condensed to form the CCD sensor unit 1.
At 6, it is converted into an electric signal. The first surface of the original 3 is read in the above process.

Next, the document conveyed by the large roller 8 and the third driven roller 11 is conveyed in the direction of the driving roller 23, and in the process of being conveyed in the direction of the document discharge roller 7, the contact type image sensor unit 20. The second surface corresponding to the back surface of the first surface of the original 3 is read by, and then the original is discharged by the original discharge roller 7 to the outside of the apparatus.

The drive roller 23 and the document discharge roller 7 described above are driven by a motor 115, which is a second pulse motor, and this serves as a second document transport section. Further, reference numerals 24 to 28 are optical sensors for detecting the front and rear ends of the fed original sheet, and the original conveyance control is performed according to the input from these optical sensors 24 to 28. Reference numeral 29 is a photo sensor for detecting the document width.

FIG. 2 is a block diagram of the main functions of the image control system of the image reading apparatus. CIS in the figure indicates a contact image sensor. The CCD sensor unit 16 and the CIS sensor unit 20 are the image processing unit 1.
The image reading information is sequentially converted into an analog image signal 107 according to the timing signal 105 generated by the timing generation function built in the No. 02 and output.

The A / D conversion unit 101 also converts the analog image signal 107 output from the CCD sensor unit 16 and the CIS sensor unit 20 into a digital image signal 108 in accordance with the timing signal 106 from the image processing unit 102. The digital image signal 108 is sent to the image processing unit 10
2 is input, and processing such as shading correction is performed. The image processing unit 102 writes / reads image information to / from the image memory unit 103 via the memory I / F 116.

Further, when writing image information, image processing for enlargement / reduction is also performed. The CPU 104 executes overall control of the document reading device 19. CPU 104
Setting and control of the image processing unit 102 and reading and writing of image information are performed via the CPU bus 109.

Further, the operation unit 110 gives a reading mode setting and a reading operation start instruction, and the display unit 111
, Single-sided or double-sided scanning mode, automatic scaling function to set the magnification ratio of the read image and the size of the document to the specified image size, the setting of the reading resolution, and the document with multiple originals of different sizes mixed Set the mode such as mixed loading mode.

Reference numeral 113 is a motor driver section, which is a driver circuit for driving the motors 114 and 115 for driving the transport rollers of the first and second document transport control sections. In addition, the motor driver unit 113
Indicates the pulse from each pulse motor to the CPU 10
By inputting to 4 and counting, the drive distance of the motor (movement distance of the document) can be measured. Reference numeral 112 is a sensor signal input unit for fetching signals from various sensors into the CPU 104.

The CPU 104 controls the drive of the motors 114 and 115 via the motor driver unit 113 based on the input of the magnification / reading resolution from the operation unit 110. That is, the reading conveyance direction (sub-scanning direction)
The variable magnification or resolution conversion is achieved by keeping the CCD or CIS reading speed constant and changing the motor driving speed. For the scaling in the reading main scanning direction, the image processing unit 102 performs scaling and resolution conversion by linear interpolation.

The size of the original is determined using the data of the signal input section 112 based on the outputs of the optical sensor 28 and the photosensor 29, and the original is conveyed based on the outputs of the optical sensors 24, 25, 26 and 27. Performs control, etc.

Next, a method of determining the document size in the mixed loading mode for reading a document in which a plurality of documents of different sizes are mixed will be described. When the leading edge of the document turns on the optical sensor 28 shown in FIG. 1, the photo sensor 29 detects the document width. As shown in FIG. 5, the photo sensor 29 is arranged in the main scanning direction of the document, and detects the document width by this. The direction A shown in FIG. 5 corresponds to the front side in FIG. Optical sensors 501-5 shown in FIG.
If all of 04 are OFF, A5R size, if sensor 501 is ON, B5R size, sensor 502
If is ON, A5 or A4R size, sensor 5
When 03 is ON, B5 size or B4 size,
When sensor 504 is ON, A4 size or A3
The size is determined, and further, the optical sensor 27 determines large paper or small paper to distinguish between paper sizes of the same width (A3 and A4, etc.).

Therefore, when the automatic scaling mode is set in the mixed original mode, the CPU 104 determines the scaling ratio for each original according to the determined paper size and the set image size. Further, the transport speed of the document at the reading position is determined according to the determined scaling ratio, and the processing of the image processing unit 102 also changes the linear interpolation process according to the scaling ratio.

Next, the operation of controlling the conveyance of a document at the reading position when the automatic variable magnification mode in the mixed original document mode is set will be described below with reference to FIGS. 4 (a) to 4 (e). .

FIGS. 4 (a) to 4 (e) are diagrams schematically showing the document conveying portion of FIG. 1, and the actual flow of paper conveyance by automatic scaling in the document mixed mode will be described below.
First, the document feed roller 4 to the third driven roller 11 are used as the first transport unit, and the motor 114 is controlled to control the document transport of the first transport unit. Next, the drive roller 23 to the document discharge roller 7 are used as the second transport unit, and the motor 115 is controlled to control the document transport of the second transport unit. The large roller 8 and the third driven roller 11 are driven by a motor 114, and the drive roller 23 and the document discharge roller 7 are driven by a motor 115. The motor 114 and the motor 115 are stepping motors.

Further, reference numerals 24, 25 and 26 are optical sensors for respectively detecting the conveyed paper as described above. S1 is the CCD which is the first reading unit in FIG.
Reading by the sensor unit 16, S2 represents reading by the CIS sensor unit 20 which is the second reading unit.

FIGS. 4A to 4E are diagrams showing the flow of originals in a time series. First, as shown in FIG. 4A, the optical sensor 24 is turned off while the document 1 is being conveyed.
When it becomes N, the leading edge of the original 1 which is the preceding original is detected, and the speed V corresponding to the size of the original 1 is detected.
At 1, the second driven roller 10 and the third driven roller 11 are rotated. The speed V1 is a speed according to the scaling ratio. Then, the first surface of the original 1 is read by the CCD (S1) while the original 1 is being conveyed. At this time, when there is no preceding document, the drive roller 23 and the document discharge roller 7 are set to V1.
You may rotate at the speed of.

Next, as shown in FIG. 4B, when the leading edge of the original 1 is detected by the optical sensor 25, the drive roller 23 and the original discharge roller 7 which are the second conveying section are operated to detect the original 1. Accelerate to reading speed V1. Then, in the case of a double-sided original, the second side is read by CIS (S2) at the speed V1.

Next, in FIG. 4C, the rear end of the original 1 is detected by turning off the optical sensor 24 in the conveying process, and the motor pulse from that point is detected by the CPU 10.
The count of 4 detects that the document 1 has reached the position where it passes through the third driven roller 11. Then, when the document 1 passes through the third driven roller 11, the second driven roller 10 and the third driven roller 11 of the first transport section are provided.
Is accelerated or decelerated to the variable speed V2 according to the document size of the document 2 which is the next document. At this time, the original 2 which is the next original is waiting in front of the second driven roller 10 until the rotational speeds of the second driven roller 10 and the third driven roller 11 of the first conveying unit reach V2.

Next, in FIG. 4 (d), after the rotational speeds of the second driven roller 10 and the third driven roller 11 of the first conveying section reach V2, the first surface of the original 2 is CCD (S1). Read at. When the optical sensor 25 is turned off, the trailing edge of the document 1 is detected, and by counting the motor pulses from that point, it is detected that the document 1 has reached the position where it exits the document discharge roller 7. Then, after the second surface of the original 1 has been read and the trailing edge of the original 1 has passed through the original discharge roller 7, the drive roller 2 of the second conveyance unit
3, the document discharge roller 7 accelerates or decelerates to the variable speed V2 according to the document size of the document 2 which is the next document.

Next, in FIG. 4 (e), the rotation speeds of the drive roller 23 and the document discharge roller 7 of the second conveying section are V2.
After reaching, the second surface of the original 2 is read by CIS (S2). Then, when the optical sensor 25 is turned off, the rear end of the original 2 is detected, and by counting the motor pulse from that point, it is detected that the original 2 has reached the position where it exits the original discharge roller 7. After that, the speed is changed according to the size of the next original.

Subsequent originals are read by repeating the above operation. The above operation is performed until all the originals on the original tray 3 are read, and after all the originals are read, the normal standby state is entered.

As described above, according to this embodiment, in the image forming apparatus provided with the image reading apparatus capable of reading both sides, when the automatic scaling is designated in the mixed original mode, the first surface of the previous original is read. When the trailing edge of the document passes through the first transport roller during the transport for reading the second surface by the CIS after the document is read by the CCD while transporting the document, the speed of the first transport roller is set to the speed of the next document. By scanning the first side of the next original by accelerating or decelerating to a variable speed suitable for the size, it is possible to shorten the space between the originals as much as possible and improve the reading performance.

Although the above-described embodiment has been described only with respect to the image reading apparatus alone, it can be applied to the reading unit mounted in the copying machine. In this case, when the automatic scaling is set, the original size and the recording paper size are compared, the scaling ratio is determined for each original, and the original conveying speed is controlled.

[0039]

As described above, according to the present invention, the first surface of the previous original is conveyed by the first conveying means even in the mixed original mode in which the automatic scaling is designated when the both sides are simultaneously read. , The second surface is conveyed by the second conveying means after being read by the first original reading means, and when the trailing edge of the original leaves the first conveying means during reading by the second original reading means, By accelerating or decelerating the conveying speed of the first conveying means to an arbitrary variable speed corresponding to the size of the next original and reading the first side of the next original, it is possible to achieve the optimum document interval. Read performance can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of an image reading apparatus of the present invention.

FIG. 2 is a block diagram of main functions of an image control system of the image reading apparatus.

FIG. 3 is a configuration diagram of an image reading apparatus having a conventional double-sided reading mechanism.

FIG. 4 is an explanatory diagram of paper conveyance control in the embodiment.

FIG. 5 is a schematic view of the sensor seen from the main scanning direction.

[Explanation of symbols]

1 Document Feeding Device 2 Document Tray 3 Document 4 Document Feeding Roller 5 Separation Pad 6 Intermediate Roller Pair 7 Document Ejecting Roller 8 Large Roller 9 First Driven Roller 10 Second Driven Roller 11 Third Driven Roller 12 Flowing original document glass 13 Second reading unit (exposure unit) 14 Mirror unit 15 Lens 16 CCD sensor unit 17 Document guide plate 18 Jump table 19 Document reading device 20 First reading unit (contact image sensor unit) 20 CIS sensor unit 21 Standard white Plate 22 Reference White Plate 23 Driving Rollers 24 to 28 Optical Sensor 29 Photo Sensor 101 A / D Converter 102 Image Processing Unit 103 Image Memory Unit 104 CPU 109 CPU Bus 110 Operation Unit 111 Display Unit 112 Sensor Signal Input Unit 113 Motor Drive Parts 114, 115 Motor 116 Memory I / F 301 First reading sensor (CCD) 302 second reading sensor (contact image sensor) 303 and 304 reference white plate 501 to 504 sensor

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H108 AA14 JA15                 5C062 AB02 AB17 AB32 AB33 AB41                       AC02 AC09 AC12 AC67 AC68                       AD06 BA04                 5C072 AA01 BA03 BA09 CA02 DA02                       DA04 EA05 EA07 NA01 NA05                       RA04 TA05 WA02

Claims (3)

[Claims] 1. A document size determining means for determining a document size before reading a document, a first document reading means for reading a first side of a document by flow scanning, and a second side of a document for scanning by flow scanning. A second original reading unit located downstream of the first original reading unit; a first conveying unit that conveys an original in order to perform a flow reading in the first original reading unit; Second conveying means for conveying an original in order to perform flow reading in the original reading means, and an automatic magnification setting means for automatically setting the original magnification so that the original size falls within a predetermined size when the original is read. And a conveyance control means for changing the speeds of the first conveyance means and the second conveyance means based on the magnification set by the automatic magnification setting means, and an original in which a plurality of originals of different sizes are mixed. A mixed original document mode setting unit for setting a mixed original document mixed mode, the mixed original document mode is set by the original mixed document mode setting unit, and the automatic scaling is specified by the automatic scaling setting unit. An image reading apparatus characterized in that the transport speeds of the first transport means and the second transport means are independently controlled. 2. The image reading apparatus according to claim 1, wherein the original mixed loading mode is a double-sided reading mode. 3. A first surface of a front original is conveyed by the first conveying means and read by the first original reading means, and then a second surface of the front original is conveyed by the second conveying means. , While the second original reading means is reading, when the trailing edge of the original leaves the first conveying means, the speed of conveyance of the first conveying means is adjusted to an arbitrary variable speed according to the size of the next original. The image reading apparatus according to claim 1, wherein the first surface of the next original is read by accelerating or decelerating to the next.