JP3200906B2 - Image reading device - Google Patents

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 for reading a document while the document is being conveyed, and is characterized mainly by control for reading the back side of a double-sided document.

[0002]

2. Description of the Related Art Conventionally, there has been used an apparatus which reads both sides of an original by reading the original while the original is being conveyed, that is, by so-called panning.

In such a reading device, an image sensor is fixedly arranged in a document conveying path, the surface of the document is read while the document is being conveyed by the conveying device, and the document is inverted at one end of the conveying path. An apparatus has been proposed which reads the back side of a document conveyed in the reverse direction by an image sensor (Japanese Patent Laid-Open No. 2-63262).
issue).

[0004]

However, in the above-described conventional reading apparatus, since the image sensor is fixed, the time from the start of transport of the document to the start of reading the back side of the document is constant. In some cases, it takes a long time to finish reading a document even when the length of the document is short.

For this reason, for example, in a digital copying machine used in combination with a printer, it takes a lot of time to copy a large number of documents, and the overall copying speed cannot be improved.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to shorten the time required to read a document by shortening the time required to start reading the back of a double-sided document.

[0007]

According to a first aspect of the present invention, there is provided an apparatus for moving a document along a conveyance path in a first direction from one end thereof to the other end thereof and vice versa. conveys in a second direction, reading to read the document conveying means having a reversing means for a document disposed on the other end side of the conveying path is reversed, the document being conveyed by the document conveying means is stopped Means for moving the reading means along the transport path, and the reading means stopped at a first position along the transport path in a duplex mode for reading both sides of a document. By the first
After the front side of the document being conveyed in the direction is read, it is turned over by the reversing means and conveyed in the second direction.
To read the back side of the document, said reading means from said first position, between said first position and said inverting means
To a second position along the transport path of the
And control means for controlling said moving means so as to stop at said position. According to a preferred example, the reversing means reverses the original by turning the original in a U-turn direction, and the second position is such that the rear surface of the original is obstructed at its rear end after the original is inverted by the reversing means. Where it can be read the fastest without being read
From the first position in the first direction by the following equation:
L = Lm− (Ld−Lp) / 2, where Lm is the distance from the first position to the reversing means.
The length Ld of the transport path is the length of the document LP is the length of the reversing path of the reversing means.

[0008]

In the double-sided mode, first stop at the first position.
The reading means reads the surface of the document. So
Thereafter, the reading unit is moved along the transport path by the moving unit, and is positioned at the second position by the control unit.

[0009] The second position, the document is the position which can be read fastest after being inverted by the inverting means of the original conveying means, described above, for example, depending on the length of the document
It is calculated by the following equation . The back side of the inverted document is
Read at the second position.

[0010]

FIG. 1 is a sectional front view showing the entire structure of a copying machine 1 using a reading device IR according to the present invention, and FIG. 2 is a front view of an operation panel OP.

In these figures, a copying machine 1 has a scanning system 10 for reading an original and converting it into an image signal.
An image signal processing unit 20 for processing an image signal sent from
A memory unit 30 for switching image data input from the image signal processing unit 20 to a printer device as it is or to store the image data in a memory, and the like based on the image data input from the memory unit 30;
Processing unit 4 for driving two semiconductor lasers 61 and 62
0, an optical system 60 for guiding the two laser beams from the semiconductor lasers 61 and 62 to different exposure positions on the photosensitive drum 71, and developing and transferring and fixing the latent image formed by the exposure on paper. An image forming system 70 for forming an image, an operation panel OP provided on the upper surface of the main body, a document transport section 500 for transporting a document and reversing the front and back as necessary, and for feeding a sheet to a transfer position again Of paper re-feeding section 600 of FIG.

The scanning system 10 and the image signal processing unit 20
The reading device IR is also provided by the print processing unit 40,
The printer device PRT is constituted by the optical system 60, the image forming system 70, and the like.

The scanning system 10 includes an exposure lamp 11 and a first mirror 12, and second and third mirrors 13a and 13 which are mounted on a scanner 19 which moves below a platen glass 18.
b, condensing lens 14, dichroic mirror 15,
It comprises photoelectric conversion elements 16 and 17 using a CCD array or the like, a scan motor M2, and the like.

The image signal processing section 20 processes the image signals output from the two photoelectric conversion elements 16 and 17, and determines each pixel of the original image with a specific color (second color) and other colors (first color).
And outputs image data with color data to the memory unit 30.

The print processing unit 40 sorts the image data with the color data sent thereto into the two semiconductor lasers 61 and 62, and determines the difference between the exposure positions corresponding to the two semiconductor lasers 61 and 62. Accordingly, the image data given to one semiconductor laser 62 is delayed.

The optical system 60 includes semiconductor lasers 61 and 62,
Dichroic mirror 63 for combining two laser beams, polygon mirror 65 for deflecting the combined laser beam, main lens 69, reflection mirror 67a, dichroic mirror for separating the combined laser beam into the original two laser beams 68, reflecting mirrors 67b, 67c and the like.

The image forming system 70 includes a development transfer system 70A, a transport system 70B, and a fixing system 70C. The development transfer system 70A includes a photosensitive drum 71 that is driven to rotate in a counterclockwise direction in FIG. 1, a first charging charger 72a disposed around the photosensitive drum 71 in order from the upstream side in the rotation direction, and a first developing device 7
3a, a second charging charger 72b, a second developing unit 73b,
It comprises a transfer charger 74, a separation charger 75, a cleaning unit 76 and the like.

The first developing unit 73a contains a two-component developer consisting of a red toner and a carrier corresponding to the second color, and the second developing unit 73b stores a black toner and a carrier corresponding to the first color. Is stored.

The transport system 70B is loaded from cassettes 80a and 80b for storing the paper, size detection sensors SE11 and SE12 for detecting the paper size, a paper guide 81, a timing roller 82, a transport belt 83, and a re-feed unit 600. And horizontal transport rollers 86a-86c for transporting the fed sheets.

The fixing system 70C includes fixing rollers 84 and 84 for conveying the paper while thermocompressing the paper, a discharge roller 85, and a discharge sensor SE62 for detecting discharge of the paper.
The re-feeding unit 600 temporarily stores the sheet discharged from the discharge roller 85, and in the case of the double-side mode, reverses the front and back,
In the combining mode, the recirculation type is a type in which the sheet is fed into the horizontal transport roller 86a of the transport system 70B for image formation (printing) again without performing the reverse. Refeed unit 60
Reference numeral 0 includes a switching claw 601 for switching between discharge to the discharge tray 621 and re-feeding, a transport roller 602, a reversing roller 603, a reversing sensor SE61, and the like.

In the double-sided mode, the left end of the switching claw 601 is moved upward by a solenoid (not shown).
As a result, the sheet discharged from the discharge roller 85 is guided toward the transport roller 602 and reaches the reversing roller 603 through the transport roller 602.

When the rear end of the sheet reaches the reversing sensor SE61, the reversing roller 603 is reversed, whereby the sheet is conveyed toward the horizontal conveying roller 86a, and passes through the horizontal conveying rollers 86b and c to the timing roller 82. Reach and wait. At this time, the next sheet is also sequentially conveyed at a predetermined interval, and the number of sheets that can be copied on one side of the sheet depends on the length of the sheet if there is no delay in image data. Become.

The document feeder 500 includes a document feed tray 51
The document set on the document 0 is automatically conveyed onto the document glass 18, and after the document is read by the scanner 19, the document is discharged to the discharge tray 511.

The original transport section 500 includes a paper feed roller 501,
Separating roller 502, separating pad 503, intermediate roller 50
4, registration roller 505, transport belt 506, reversing roller 507, switching claw 508, discharge roller 509, paper feed tray 510, paper discharge tray 511, document scale 51
2. A registration sensor (feed sensor) SE51 and a discharge sensor SE52 are provided.

The operation of the document transport section 500 differs depending on the document reading mode. The document reading mode includes a scan mode in which the document is scanned by the scanner 19 and a panning mode in which the document is transported while the scanner 19 is stopped.

Therefore, the operation of the document feeder 500 depends on whether only one side of the document is read or both sides are read.
), A panning single-sided mode, and a panning double-sided mode.

In the one-sided mode, one or a plurality of originals are set on the paper feed tray 510 with the side to be read facing upward. When the operation is started, the original is transported by the paper feed roller 501 in order from the lowermost original of the set original, the original transported by the separation roller 502 and the separation pad 503 is separated, passes through the intermediate roller 504, and is registered by the registration roller 505. The skew is corrected and the conveyor belt 5
At 06, the document is conveyed onto the document glass 18, and immediately after the rear end of the document has passed the left end of the document scale 512, the conveyance belt 506 slightly reverses and stops.

As a result, the right end (rear end) of the original contacts the edge of the original scale 512 and the original is placed on the original glass 18.
Positioned accurately on top. At this time, the leading edge of the next document has reached the registration roller 505, so that the time required for transporting the next document is reduced.

In this state, the scanner 19 scans and reads the front surface (lower surface) of the document. When the reading of the document is completed, the document is conveyed to the left by the conveyance belt 506, U-turned by the reversing roller 507, and
8 and a discharge roller 509 by the discharge roller 509.
11 is discharged. At this time, the document is discharged with the reading surface (front surface) of the document facing upward.

Next, the panning single-sided mode will be described. The panning single-sided mode is possible, for example, when performing a single copy, and performs an operation in conjunction with the scanning system 10.
In other words, until the document passes through the registration roller 505, the operation is the same as that in the above-described single-sided mode. After that, the document is transported by the transport belt 506 at a constant speed corresponding to the copy magnification, and the reverse roller 507 and the like are directly Is discharged onto the paper discharge tray 511 through the During this time, the scanner 19 is stopped at the right end of the original glass 18, and the original passes above the original, whereby the surface of the original being transported is read.

Therefore, operations such as reverse positioning of the original and scanning and return of the scanner 19 in the single-sided mode are not performed, and reading is performed at high speed. next,
The panning duplex mode will be described. In the panning double-sided mode, the operation up to reading of the front side of the document is the same as that in the panning single-sided mode described above, but during that time, the switching claw 508 is switched so that the left end thereof faces upward, and the front side is read. The conveyed document that has been conveyed makes a U-turn with the reversing roller 507, passes under the switching claw 508, and is again guided below the conveying belt 506 with the front and back reversed.

In the meantime, the scanner 19 moves to the left when the reading of the front side of the document is completed, and stands by at the back side reading position corresponding to the length of the document. The back side reading position corresponds to the second position of the present invention . When the document makes a U-turn with the reversing roller 507, the position where the leading edge and the trailing edge of the document coincide with each other, that is, the document rotates around the reversing roller 507. The returned length is slightly to the right of the position at which the length of the document matches.

FIG. 3 is a diagram showing positioning control of the scanner 19. The reading range of the original by the scanner 19 is the origin position (home position) H of the leading end of the original glass 18.
The distance is from P to the rear end position EP of the original glass 18. The surface of the document is read at the origin position HP.
If the origin position HP is L = 0, then at the rear end position EP, L =
Lm. Here, Lm is the effective length of the original glass 18, which is 432 [mm] in this embodiment.

The reversing roller 507 is moved from the rear end position EP.
The length of the reversal path, which is the path from when the document is reversed and returns to the rear end position EP again, is Lp, and the length of the document is L.
Assuming d, the reading position RP is expressed by the following equation (1).

L = Lm− (Ld−Lp) / 2 (1) Here, the length Lp of the reversing path is a value determined by design, and the length Ld of the document is determined during registration of the document during conveyance. Since it is detected by the sensor SE51, Lm = 43
2 and the back side reading position RP is L = 432−
(Ld-Lp) / 2.

Therefore, the back side reading position RP changes according to the length Ld of the document. However, when the front end and the rear end do not coincide on the upper surface of the document glass 18 (within the reading range of the document) because the document is short. , The left end (rear end position EP) of the original glass 18 is the back surface reading position RP. That is, the maximum value of L is Lm.

The original re-directed below the conveyor belt 506 is conveyed rightward by the inverted conveyor belt 506 at a constant speed corresponding to the copy magnification, and stands by at the back reading position RP during the conveyance. Since the document passes above the scanner 19, the back side of the document being conveyed is read.

When the reading of the back side of the document is completed,
The conveyance belt 506 rotates in the reverse direction, and the original is conveyed to the left.
After the document is conveyed to the right and the left end of the document reaches the conveyance belt 506, it is again conveyed to the left, and passes over the reversing roller 507 and the switched switching claw 508 to the discharge roller. By 509, the sheet is discharged onto the sheet discharge tray 511. As a result, the document is discharged with the surface of the document facing upward.

As described above, after reading the front side of the original at the origin position HP, the scanner 19 moves to position the original at the back side reading position RP. The reading can be completed in the shortest time according to, and the overall copy speed can be improved.

Next, in FIG. 2, the operation panel OP includes a liquid crystal touch panel 91, a numeric keypad 92 for inputting a setting number and a magnification, a clear key 93 for returning the setting number to a standard value "1", and a copying machine. There are provided a panel reset key 94 for returning the set values in 1 to a standard value, a stop key 95 for stopping the copy operation, and a start key 96 for starting the copy operation.

The liquid crystal touch panel 91 displays various states of the copying machine 1 such as occurrence of JAM, serviceman call, occurrence of paper empty, operation mode of the copying machine 1 such as exposure level, magnification, paper, and other various information. In addition to the display, an input for selecting a copy mode such as a one-sided copy mode, a two-sided copy mode by panning, and a 2-in-1 mode is performed.

Next, the control unit 100 will be described. 4 and 5 are block diagrams showing the configuration of the control unit 100 of the copying machine 1. The control unit 100 includes eight CPUs 101 to
108, each of these CPUs 101 to
8, ROMs 111-111 each storing a program.
118 and RA serving as a work area for program execution
M121 to M128 are provided. Note that the CPU 10
Reference numeral 6 is provided in the memory unit 30.

The CPU 101 performs control relating to input of signals from various operation keys on the operation panel OP and display. The CPU 102 controls each unit of the image signal processing unit 20, and the CPU 103 controls the driving of the scanning system 10. The CPU 104 controls the print processing unit 40, the optical system 60, and the image forming system 70, and the CPU 105 controls the control unit 1
A process for adjusting the overall timing of 00 and setting the operation mode is performed.

By controlling the memory unit 30, the CPU 106 temporarily stores the read image data in a memory (image memory 304), reads the image data, and outputs the read image data to the print processing unit 40. Thereby, the reading device I
The R and the printer device PRT are independently controlled to improve the copy speed.

The CPU 107 controls the document transport unit 500, and the CPU 108 controls the re-feed unit 600. Serial communication is performed between the CPUs 101 to 108 by interruption, and commands, reports, and other data are exchanged.

Next, each processing section for processing image data will be described. The image signal processing unit 20 includes an A / D converter,
The image processing apparatus includes a shading correction unit, a color determination unit that determines the color of a pixel of a document based on image data, a scaling unit, and an image quality correction unit.

The image signal input from the photoelectric conversion elements 16 and 17 is quantized by the image signal processing section 20 into 8-bit image data for each pixel, subjected to various processes, and output as image data D2. You. At the same time, 1-bit color data DC indicating whether or not the specified specific color is output corresponding to each pixel of the image data D2.

FIG. 6 is a block diagram of the memory unit 30. The memory unit 30 includes a switching unit 301, C
A binarization processing unit 302 that creates binary data based on parameter settings from the PU 106; a multiport image memory 304 having a capacity of two A4-size pages at 400 dpi; and a compressor 311 that can operate independently. And a code processing unit 305 having a decompressor 312, a code memory 306 having multiple ports, a rotation processing unit 307, a CP
It is composed of a multi-value processing section 308 that creates multi-value data based on parameter settings from the U 106, and a CPU 106 that controls all of them.

The switching section 301 controls each control signal S
It consists of five bus gates whose on and off are controlled by G. Each control signal SG is active or non-active according to the operation mode, and the connection state of the switching unit 301 is set by the combination thereof to control the flow of image data.

When the image data D2 is written into the image memory 304, the code processing unit 305 reads and compresses the data to create code data, and writes the code data into the code memory 306. Also, according to a command from the CPU 106,
The code data written in the code memory 306 is read and decompressed to create image data.
Write to 04.

When one page of image data is generated in the image memory 304 by the decompression, the image data is read out, rotated if necessary by the rotation processing unit 307, and multi-valued by the multi-value processing unit 308. Image data is generated and output as image data D3. The compressor 311 and the decompressor 312 can operate independently and in parallel with each other, and data is DMA-transferred between them and the code memory 306.

The operation modes of the memory unit 30 include:
There are a direct connection mode, a memory mode, and a direct connection memory mixed mode. In the memory mode, there are two operations, a memory mode write operation and a memory mode read operation. The direct connection memory mixed mode is a mode in which the direct connection mode and the memory mode are mixed.

In the direct connection mode, the image data D2 output from the image signal processing unit 20 is output as it is to the print processing unit 40 as image data D3. In the memory mode, the image data D2 is binarized and then taken into the image memory 304 to perform a predetermined process.
4 and output to the print processing unit 40 as image data D3.

That is, in the memory mode, at the time of the memory mode write operation (from the reading device to the memory), the image data D2 and the color data DC are output to the binarization processing unit 302, and after the binarization, the image memory The code is written to the code memory 304, and further compressed and written to the code memory 306.

In the memory mode read operation (from the memory to the printer), the expanded image data is read from the image memory 304 and output as image data D3 and color data DC.

In the direct memory mixed mode,
The image data D2 and the color data DC are output as they are to the print processing unit 40 as the image data D3 and the color data DC.
The data is written to the image memory 304 via the value processing unit 302.

The operation mode of the memory unit 30 is automatically selected according to the copy mode. Next, the relationship between the original reading operation and the printing operation on paper will be described with reference to an example.

First, the case where two two-sided originals are copied onto one side of a sheet (double-sided original single-sided copy mode) will be described. The reading operation is performed in the order of the front side, the back side, the first front side, and the back side of the second (last) sheet of the two originals set on the paper feed tray 510 with the front side up, It is stored in the memory unit 30.

After the reading operation of the back surface of the second document is completed, image data is read from the memory unit 30 in the order of the back surface of the second document, the front surface, the first back surface, and the front surface, and the printing operation is performed. Are printed on the front surfaces of the first to fourth sheets, respectively, and are sequentially discharged.

Next, a case where two two-sided originals are copied on both sides of a sheet (double-sided original double-sided copy mode) will be described. In this case, the reading operation of the original and the reading operation from the memory unit 30 are the same as those in the case of the single-sided copy described above.
The image data read from the memory unit 30 is
The front side and the back side of the first sheet are printed and discharged in the order of the second side and the back side.

Next, in a case where two double-sided originals are combined on one side of one sheet of each sheet and copied (double-sided original 2i
(n1 copy mode) will be described. In this case,
The operation of reading the original is the same as that of the above-described one-sided copy.

In the printing operation, from the memory unit 30, the second surface, the back surface, the first surface,
The sheets are read in the order of the back side, and are printed and discharged in the order of the first half, the second half of the front side of the first sheet, and the first half, the second half of the front side of the second sheet.

As described above, in the copying machine 1 according to the present embodiment, the reading device IR and the printer device PRT can operate independently of each other, and the order of printing is affected by the order of reading originals. Not receive. The writing (at the time of reading the original) and the reading (at the time of printing) in the memory unit 30 are performed by independent circuit blocks, so that the reading of the original and the printing on the paper can be performed in parallel. As a result, the copying speed is increased and the productivity is improved.

Next, based on the flowchart, the copying machine 1
Will be described. FIG. 7 is a flowchart of the main routine of the CPU 103. CPU 103 is the scanning system 10
Control. In the case of the scan mode (Yes in Step # 33), scanning control for causing the scanner 19 to scan is performed (Step # 34). In the case of the follow shot mode (No in Step # 33), slider positioning control is executed. Is performed (step # 35).

When a motor pulse interrupt occurs due to a motor pulse generated in synchronization with the rotation of the scan motor M2, the interrupt interval time of the motor pulse is measured (step # 37), and the power supply to the motor is turned on / off (step # 37). 38), counting the number of motor pulses (step # 39) and the like.

FIG. 8 is a flowchart of the main routine of the CPU 106. The CPU 106 controls the memory unit 30. A command reception process from another CPU is performed (step # 62), a status transmission process is performed (step # 63), a write control to the image memory 304 is performed (step # 64), and a compression control is performed (step # 65). ), Decompression control is performed (step # 66), and reading control from the image memory 304 is performed (step # 6).
7).

FIG. 9 is a flowchart of the main routine of the CPU 107. The CPU 107 is a document transport unit 500
Control. The document is separated and the skew is corrected.
To feed the original (step #)
73) If the mode is the one-sided original mode (step # 7)
If YES in step 4, a one-sided document transport control process is performed (step # 75). If the mode is the duplex document mode, a duplex document transport control process is performed (step # 76).

In steps # 75 and # 76, the transport belt 5
06, the document is positioned at a predetermined reading position and transported to the reversing roller 507, and whether the document that has reached the reversing roller 507 is discharged as it is or transported again to the transport belt 506 is controlled. Is different between a one-sided original and a two-sided original. Step # 76 will be described in detail in a later subroutine.

FIG. 10 is a flowchart showing the slider positioning process in step # 35. First, in the panning single-sided mode (Yes in step # 121), the scanner 19 is used to read only the front side of the document.
Is set to L = 0, which is the origin position HP (step # 122).

In the panning double-sided mode (NO in step # 121), when the original whose front surface is being read has passed the origin position HP (YES in step # 123), the target position L is set to the rear surface. L = read position RP
432- (Ld-Lp) / 2 (step #
124). At this position, the back side of the document can be read without being disturbed by the rear end of the document.

If the target position L set in step # 124 exceeds "432", the target position L is set to "43".
2 "(steps # 125 and 126). If the target position L is a negative value, it is considered that a document conveyance error has occurred, and the document is stopped as a document jam (steps # 127 and 128).

FIGS. 11 and 12 are flow charts showing the double-sided document conveyance control processing in step # 76. In this subroutine, when the double-sided document mode is set, the document is registered in the registration sensor SE51 of the document conveyance unit 500.
Is controlled until the sheet is discharged to the sheet discharge tray 511.

The original conveying section 500 is driven by a motor (not shown), and the rollers and the conveying belt are driven by transmitting the driving of the motor via a clutch. The rotation amount of each roller, that is, the transport amount of the document, is obtained by calculating the rotation amount of the motor from the motor pulse. The speed of this motor is controlled similarly to that of the scan motor M2.

The document that has reached the registration sensor SE51 is conveyed to the left under the conveyance belt 506 (steps # 701 to 703). At this time, the origin position H
An image on the front side of the document is read by the scanner 19 waiting at P.

When the document reaches the discharge sensor SE52, the switching claw 508 is switched by the solenoid (step # 707), and the document is U-turned by the reversing roller 507 and turned upside down (step # 70).
8) Then, the document is conveyed right below the conveyance belt 506 with the back side of the document facing down (step # 713). At this time, the image on the back side of the document is read by the scanner 19 waiting at the back side reading position RP.

After the trailing edge of the document has passed the discharge sensor SE52 (YES in step # 715), the document is transported by a distance controlled by the motor pulse counter 2 (step # 715).
716, 722). At this time, the rear end of the document has reached the back surface reading position RP, and the reading of the back surface of the document is completed.

Further, the original is reversed in the same manner as described above (steps # 723 to 737), and when the original is discharged with the front side of the original up (YES in step # 746), the drive system is stopped (step # 746). Steps # 747 and 74
8).

However, after detecting the leading edge at the time of discharge of the original (YES in step # 739), the process stands by for the conveyance of the next original, and when the next original is detected (step # 744). , 751), and the carrying operation is continuously performed (steps # 745, 752).

The motor pulse counters 1 and 3 have a fixed value depending on the length Lp of the reversing path, and the motor pulse counter 2 has a variable value depending on the length Ld of the document. This is the minimum value that allows the inverted document to completely pass through the back side reading position RP. Further, the motor pulse counter 4 is different from the motor pulse counter 2 in that the rear end of the document reaches below the conveyance belt 506 and the conveyance belt 506 is rotated forward to take the minimum value that can be conveyed below the reversing roller 507. It is a fixed value.

In the above-described embodiment, the transport path is provided along the upper surface of the original glass 18, but other transparent guide members, bent guide members, a transport path in which a plurality of rollers are disposed, or a simple The transport path may be a space only. Further, it may be a reading unit equipped with such a contact image sensor in place of the scanner 19.

[0081]

According to the present invention, the reading start time of the back surface of a double-sided document or the like can be shortened to shorten the document reading time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional front view showing an entire configuration of a copying machine using a reading apparatus according to the present invention.

FIG. 2 is a front view of an operation panel.

FIG. 3 is a diagram illustrating positioning control of a scanner.

FIG. 4 is a block diagram illustrating a configuration of a control unit of the copying machine.

FIG. 5 is a block diagram illustrating a configuration of a control unit of the copying machine.

FIG. 6 is a block diagram of a memory unit.

FIG. 7 is a flowchart of a main routine of a CPU 103;

FIG. 8 is a flowchart of a main routine of a CPU 106;

FIG. 9 is a flowchart of a main routine of the CPU 107.

FIG. 10 is a flowchart showing a slider positioning process.

FIG. 11 is a flowchart illustrating double-sided document conveyance control processing.

FIG. 12 is a flowchart illustrating double-sided document conveyance control processing.

[Explanation of symbols]

Reference Signs List 10 scanning system (reading means) 18 document glass (transport path) 19 scanner (reading means) 100 control unit (control means) 500 document transport unit (document conveying means) 507 reversing roller (reversing means) M2 scan motor (moving means) Ld Document length RP Back reading position ( second position ) IR reading device (image reading device)

Continuation of the front page (72) Inventor Akio Nakajima 2-3-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka Inside the Osaka International Building Minolta Camera Co., Ltd. (56) References JP-A-63-218977 (JP, A) JP-A-2-48679 (JP, A) JP-A-2-281970 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 1/04-1/207 G03G 15/00 107 G03G 15/04-15/043 H04N 1/00-1/00 108

Claims (2)

(57) [Claims] An original is transported along a transport path in a first direction from one end thereof to the other end thereof and in a second direction opposite thereto, and the original is disposed at the other end of the transport path. Document transporting means provided with reversing means for reversing the front and back, reading means for reading the document being transported by the document transporting means in a stopped state, moving means for moving the reading means along the transport path, and document. in duplex mode scanning both sides of the conveying path
By the reading means stopped at a first position along
After the front side of the original being conveyed in the first direction is read , the original is turned over by the inverting means and the second side is read.
In order to read the back side of the document being conveyed in countercurrent, from the first position to the reading means is moved to a second position along said transport path between said first position and said inverting means And a control means for controlling the moving means so as to stop at the second position. 2. The reversing means is for turning the original upside down by turning the original, and the second position is such that the back of the original is obstructed at its rear end after the original is inverted by the inverting means. Where the position can be read fastest without being
Defined from the first position in the first direction by the following equation:
The image reading device according to claim 1, wherein L is a distance from the first position to the reversing unit. L = Lm- (Ld-Lp) / 2
The length Ld of the transport path is the length of the document LP is the length of the reversing path of the reversing means.