JP2004080171A - Image reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize downsizing of an image reader employing a sheet-through system compatible with mixed originals and simplicity of its structure. <P>SOLUTION: The image reader is provided with: a feed paper side path 2a; a carrying path 2b; a paper discharge side path 2c, and an inverted path 2d, which form paths through which an original is carried; and rollers such as an extra carrier roller 4f and a press carrier roller 4g. A length sensor 5 for sensing the length of the original in the carrying direction is placed above the outside of the carrying path 2b, and a read section 3 is placed at an opposite position in the vicinity of the lowest end of the circulation carrying path 2b. The read section 3 reads an image of the passing original and a CCD 9 reads the width of the original. Thus, the need for a width sensor is eliminated to downsize the reading apparatus and simplify its structure. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image reading apparatus capable of duplex reading of mixed originals including originals of different sizes, and more particularly, to reducing the size of the apparatus and simplifying the configuration by eliminating the need for a sensor for detecting the width of the original. is there.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there is a sheet-through type image reading device that reads an image while transporting a document. In some cases, a size is detected every time, and a document reading process is performed using the detected size.
[0003]
A sheet-through type image reading apparatus that supports reading of mixed originals includes a width sensor for detecting an original width in a conveying path of the original formed by a plurality of conveying rollers, a length sensor for detecting a length, and A reading unit for reading is arranged, and a control unit for controlling the rotation direction and the number of rotations of the transport roller is provided. Regarding the width sensors, a number of width sensors corresponding to the types of the standard sizes to be read by the apparatus are arranged so that the document widths of the standard sizes such as A3 and A4 can be detected.
[0004]
[Problems to be solved by the invention]
In the image reading apparatus corresponding to the mixed original described above, since a plurality of width sensors are arranged corresponding to each fixed size of the original, it is necessary to secure a large space for arranging the width sensors, and the apparatus becomes large. There is. There is also a problem that the arrangement structure and the electrical connection structure are complicated by the large number of width sensors. Such a problem is particularly remarkable in an image reading apparatus that is capable of reading both sides of a document because a reversing mechanism for reversing the direction of document transport is provided.
[0005]
The present invention has been made in view of such a problem, and an object of the present invention is to provide an image reading apparatus capable of realizing miniaturization and simplification of a structure in a sheet-through type image reading apparatus corresponding to mixed originals. Aim.
Another object of the present invention is to provide a sheet-through type image reading apparatus that performs one-sided reading and two-sided reading of a document while ensuring miniaturization and simplification of the structure.
[0006]
[Means for Solving the Problems]
An image reading apparatus according to a first aspect of the invention reads an image of a document which is arranged in the main scanning direction for reading the document and which is conveyed in the sub-scanning direction by an image sensor which outputs an output signal related to the reading. And an image reading apparatus provided with a transport path for a document passing through the reading section, provided on the transport path, a length detecting means for detecting the length of the document in the transport direction, and A reversing path that does not pass through the reading unit from the downstream position in the conveying direction to the upstream position from the reading unit and does not pass through the reading unit; a reversing unit that performs reverse conveyance of the document conveyed to the downstream position via the reversing path; The length of the document conveyed along the conveyance path is detected based on the detection result of the length detection unit, and the width of the document in the direction orthogonal to the conveyance direction of the document is detected based on an output signal of each image sensor. Do Control of the reversing conveyance of the reversing means for the document conveyed to the downstream position, and the length and width detected by the reading unit for the document conveyed on the conveyance path for the second and / or third time. And control means for performing control for performing reading in accordance with the data.
[0007]
In the first invention, since the document width is detected based on the reading of the image sensor of the reading unit, a plurality of width sensors provided for each fixed size can be omitted, and the space for the arrangement position of the width sensor can be omitted. Thus, the size of the device can be reduced. In addition, by omitting the width sensor, the arrangement and electric wiring of the width sensor are not required, and the structure related to the width sensor can be simplified.
[0008]
When the original is transported on the transport path for the first time, only the length and width of the original are detected, and when the transport is performed on the second and subsequent transport paths, the detected length and width of the original are used. Since the reading process is performed, it is possible to recognize the size of the document before performing the reading process, and it is possible to surely perform the process related to the enlargement or reduction of the magnification. Further, the conveyance speed at the time of reading the original can also be controlled in accordance with the scaling factor, so that an appropriate reading process can be realized for each original of the mixed original.
[0009]
In the image reading apparatus according to a second aspect of the present invention, when the control unit performs one-sided reading of the document, the control unit does not read the document conveyed on the conveyance path for the second time and conveys the conveyance path for the third time. It is characterized by controlling to read a document to be read.
[0010]
According to the second aspect of the invention, when performing one-sided scanning, it is possible to perform document conveyance and reading processing corresponding to one-sided scanning while ensuring the miniaturization and simplification of the apparatus. That is, in the sheet-through type image reading apparatus, the original to be read is basically placed on the paper feed tray with the original face up, so that the original conveyed from the paper feed tray is first read by the reading unit. , The document surface faces the reading unit.
[0011]
However, in the present invention, in order to reduce the size of the apparatus and the like, only the size of the document conveyed on the first conveyance path is detected, so that the document is conveyed on the third conveyance path by the reversal conveyance of the reversing means. Since the original surface of the original to be read is opposed to the reading unit, the control unit can read the original surface by controlling the reading to be performed at the time of the third transport of the transport path. At the time of the second transport along the transport path, the document does not face the reading unit, and thus the control unit does not control the reading of the document by the reading unit.
[0012]
The image reading apparatus according to the third aspect further includes a double-sided reading receiving unit that receives a double-sided reading instruction of the document, and the control unit performs the second and third times when the double-sided reading receiving unit receives the double-sided reading instruction. It is characterized in that control is performed to read a document conveyed on the conveyance path.
[0013]
According to the third aspect of the present invention, by receiving a double-sided reading instruction, it is possible to smoothly perform a reading process of a double-sided original while ensuring the miniaturization and simplification of the apparatus. For example, if the upper side of a document placed on the paper feed tray is the front side and the loading side is the back side, the original that is pulled out of the paper feed tray and conveyed on the first conveyance path has the front side as the reading unit. The document is conveyed in an opposed state, and the document size is detected before reading.
[0014]
The document conveyed to the downstream position of the conveyance path is reversed in the conveyance direction, and the back side of the document which is conveyed for the second time in the conveyance path faces the reading unit. Done in the department. In addition, the original conveyed to the downstream position is again inverted in the conveying direction and is conveyed in the third conveying path, and the original is read by the reading unit with the front surface facing the reading unit. Therefore, the detection of the document size and the reading of both sides of the document can be reliably performed by transporting the document through the transport path a total of three times.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings showing the embodiments.
FIG. 1 is a schematic cross-sectional view of a sheet-through type image reading apparatus 1 according to an embodiment of the present invention, and automatically separates documents one by one from a paper feed tray 1a at the upper center to the left in the figure. A transport unit 2 for transport is provided, and a paper discharge tray 1b is provided below the paper feed tray 1a. A reading section 3 is provided inside a reading case 1c which is located below the transport section 2 and the paper discharge tray 1b and has a platen glass 1d attached to the upper surface on the paper discharge tray 1b side.
[0016]
The reading unit 3 fixes a CCD (Charge Coupled Device) 9 composed of a plurality of image sensors to the right of a reading case 1c in the figure, and each image sensor is adapted to read a document in the depth direction in the figure. A plurality of CCDs 9 are arranged side by side in the main scanning direction, and the length of the CCD 9 corresponding to the size in which a plurality of imaging elements are arranged side by side corresponds to the short side of A3 standard paper to be read by the image reading apparatus 1. . The reading section 3 is provided with a lens 3c in front of the reading side of the CCD 9, and a movably provided first carriage 3a containing a mirror m1 and a light source 3d and a second carriage 3b containing mirrors m2 and m3. ing.
[0017]
Therefore, when reading a still original placed on the platen glass 1d, the reading unit 3 performs reading while moving the first and second carriages 3a and 3b in the sub-scanning direction. When reading a document conveyed by the conveyance unit 2 in the sub-scanning direction, the first carriage 3a and the second carriage 3b are stopped at the illustrated position, and the document is irradiated by the light source 3d. The reflected light of the image of the document due to the irradiation is reflected by the mirrors m1 to m3 of the first carriage 3a and the second carriage 3b, and is incident on the CCD 9 through the lens 3c, whereby the reading of the document image is performed by the reading unit 3. The reading unit 3 can also detect the width of the document conveyed through the conveyance unit 2 by reading the intensity of the reflected light with the CCD 9 using the above-described optical system.
[0018]
As shown in FIG. 2, the transport unit 2 includes a paper feed path 2a that is continuous with the paper feed tray 1a as a path through which the document is transported, and a part that is continuous with the paper feed path 2a and faces the reading unit 3. A transport path 2b having a circular shape passing therethrough, a discharge path 2c extending from the transport path 2b to the discharge tray 1b, and a reversing path 2d extending from a downstream position 2e to an upstream position 2f of the transport path 2b are formed. I have. Note that the reversing path 2 d does not pass through a portion facing the reading unit 3.
[0019]
Further, a pickup transport roller 4a, a separate transport roller 4b, and a retard transport roller 4c are provided in the paper feed side path 2a, and a total of three sets of orbital transport rollers 4d and driven transport rollers 4e are provided in the transport path 2b. An extra transport roller 4f for reversing and transporting the original and a driven press transport roller 4g are provided as reversing means in the paper discharge side path 2c. The pickup transport roller 4a, the separate transport roller 4b, and the orbit transport roller 4d are driven by a document transport motor (not shown) via transmission means such as gears, and the extra transport roller 4f is a reverse motor (not shown). Driven by
[0020]
Further, a length sensor 5 for detecting the length of the original in the transport direction as a length detecting means and directly detecting the presence or absence of the original being transported is provided outside the upper portion of the transport path 2b. In addition, a reversing sensor 6 for detecting the end of the document located on the paper discharge side path 2c is provided on the paper discharge side path 2c on the side of the transport path 2b. A contact glass 8 is disposed at a position facing the vicinity of the lowermost end of the transport path 2b, and the reading unit 3 performs image reading and width detection of a document passing near the lowermost end of the transport path 2b via the contact glass 8. Do.
[0021]
As described above, the transport unit 2 does not have a large number of width sensors as in the related art. Therefore, the size of the space for arranging the width sensors is reduced, and the structure related to the arrangement and electrical connection of the width sensors is achieved. Has been simplified.
[0022]
FIG. 3 is a block diagram of a main hardware unit of the image reading apparatus 1. The image reading apparatus 1 includes a reading unit 3, an operation unit 13, a ROM 14, a RAM 15, a length sensor 5, a reversing sensor 6, a document conveying motor 7a, and a control unit 10 functioning as a width detection and control unit via a bus 11. The reversing motor 7b and the image memory 16 are connected. The control unit 10 detects the document width based on the document image data (output signal output by the CCD 9) read by the reading unit 3. This document width can be detected by analyzing the output value of each image sensor of the CCD 9.
[0023]
The operation unit 13 receives input of various operations of the image reading apparatus 1, and in particular, in the present embodiment, a single-sided reading reception unit that receives a single-sided reading instruction of a document, and a double-sided reading reception that receives a double-sided reading instruction of a document. It functions as a unit and includes various buttons such as a single-sided reading button 13a, a double-sided reading button 13b, a start button 13c, a scaling button 13d for enlargement / reduction, and a mixed reading button 13e.
[0024]
The single-sided reading button 13a is a button that receives a single-sided reading instruction when pressed down, and the double-sided reading button 13b is a button that receives a double-sided reading instruction when pressed down. The start button 13c is a button used to give an instruction to start one of the above-described one-side reading and two-side reading. When the start button 13c is pushed down without pushing down either the one-sided reading button 13a or the two-sided reading button 13b, the one-sided reading process is started.
[0025]
The magnification button 13d is a button for receiving an instruction to change the magnification for reading, and the mixed reading button 13e is a button for setting the mixed document set in the paper feed tray 1a to a reading mode. If is not depressed, the normal reading mode is set for a non-mixed original. A signal related to the instruction received by each button is sent to the control unit 10.
[0026]
The ROM 14 stores a program for executing transporting and reading processing in the image reading apparatus 1 and various data relating to the processing. The RAM 15 temporarily stores data and the like generated during execution of various processes. The length sensor 5 and the reversing sensor 6 each detect the presence or absence of a document at the detection position, and transmit a detected detection signal to the control unit 10. Further, in the case where the image reading apparatus 1 has a facsimile communication function, the image memory 16 stores, in addition to the data relating to the image of the document read by the reading unit 3, data of the image received by facsimile. .
[0027]
In response to the width detection, the control unit 10 receives a read signal from the CCD 9 of the reading unit 3 and detects the document width based on the content of each received read signal. Further, the control unit 10 as a control unit performs various controls in response to signals from each button and each sensor based on a program stored in the ROM 14.
[0028]
As specific control contents, the control unit 10 drives the original conveying motor 7a to detect the detection signal from the length sensor 5 and read the CCD 9 of the reading unit 3 for the original conveyed on the conveying path 2b for the first time. Control for detecting the length and width of the document based on the signal is performed. By detecting the length and width of the original, the control unit 10 recognizes which standard size of the original to be conveyed is. In addition, an accurate size can be detected not only for a fixed size document but also for a non-fixed size document.
[0029]
The control unit 10 detects the length of the document based on the time during which the detection signal of the length sensor 5 is received and the transport speed of the document transport motor 7a when the detection signal is detected. Further, as shown in FIG. 4A, the control unit 10 first feeds the original G placed on the paper feed tray 1a with the upper side in the figure as the front surface Ga and the lower side as the back surface Gb in the direction of the white arrow. Control for rotating each of the transport rollers 4a to 4f so as to transport the paper to the paper path 2a, the transport path 2b, and the paper discharge path 2c is performed on the document transport motor 7a and the reversing motor 7b in FIG.
[0030]
Further, when the document G is conveyed along the sheet discharge side path 2c to the position where the document G passes the downstream position 2e downstream of the reading position in the above-described conveyance, the control unit 10 reverses the rotation direction of the reversing motor 7b. As shown in FIG. 4B, control is performed so that the extra transport roller 4f and the press transport roller 4g rotate in the black arrow direction.
[0031]
The details of the reverse rotation control of the reversing motor 7b are as follows. When the rear end of the document G passes, the reversing sensor 6 that has detected the document G no longer detects the document G. In response to the change, switchback control for reversing and transporting the document G to the reversing path 2d in the white arrow direction is performed. Note that the original G conveyed to the reversing path 2d becomes the back surface Gb and the lower surface G because the document G that has been conveyed through the conveyance path 2b before the reversing.
[0032]
As shown in FIG. 5A, the document G whose first conveyance direction has been inverted in this manner passes through the inversion path 2d according to the white arrow direction and is conveyed in the second conveyance path 2b. The control unit 10 controls the rotation direction of each transport roller 4d and the like as described above. In the second transfer on the transfer path 2b, when the magnification is set by the scaling button 13d in FIG. 3, the rotation of each of the transfer rollers 4d is adjusted so that the transfer speed is in accordance with the set magnification. The control unit 10 controls the speed.
[0033]
In the second transport along the transport path 2b, when the back side Gb of the original G faces the reading unit 3 at the reading position near the lowermost end of the transport path 2b, and the control unit 10 receives a one-side reading instruction, Control is performed so that the reading unit 3 does not perform reading, and when a double-sided reading instruction is received, control is performed so that the reading unit 3 reads the back surface Gb using the detected document size. When the original G is conveyed to the paper discharge side path 2c in the second conveyance path 2b, the control unit 10 performs the switchback control shown in FIG. 4B again.
[0034]
As shown in FIG. 5B, the upper side of the document G whose direction of conveyance has been reversed for the second time becomes the front surface Ga and the lower side again becomes the back surface Gb. In the same manner as in the transfer situation, the transfer on the third transfer path 2b is performed. In the third transport along the transport path 2b, the front side Ga of the original G faces the reading unit 3 at the reading position near the lowermost end of the transport path 2b, and the control unit 10 issues either a one-side reading instruction or a two-side reading instruction. Even when the document is received, the reading unit 3 is controlled so as to read the front surface Ga using the detected document size. Since the control unit 10 performs control according to the number of times the document is transported on the transport path 2b as described above, the control unit 10 counts the number of times the document is transported on the transport path 2b.
[0035]
After this reading, the control unit 10 controls the original G conveyed to the paper discharge side path 2c so as to be sent out to the paper discharge tray 1b without being inverted. The control unit 10 performs the above-described various controls so that the image reading apparatus 1 can support single-sided reading and double-sided reading of a document.
[0036]
Next, a specific series of reading processing for a mixed original by the image reading apparatus 1 having the above-described configuration will be described with reference to the flowchart of FIG. It is assumed that a plurality of mixed originals of different sizes are previously placed on the paper feed tray 1a.
[0037]
First, the control unit 10 of the image reading apparatus 1 changes the setting from the reading mode for non-mixed originals to the reading mode for mixed originals by depressing the mixed reading button 13e (S1). Next, it is determined whether the single-sided reading button 13a has been pressed down (S2). If the single-sided reading button 13a has been pressed down (S2: YES), it is determined whether the start button 13c has been pressed down. (S3). If the start button 13c has not been pressed down (S3: NO), a loop state waiting process is performed until the start button 13c is pressed down.
[0038]
If the single-sided reading button 13a has not been pressed down (S2: NO), it is determined whether the start button 13c has been pressed down, as in the case where the single-sided reading button 13a has been pressed down (S2: YES) (S4). . When the start button 13c is depressed (S4: YES), the same processing flow as when the one-sided reading button 13a is depressed and the start button 13c is also depressed (S3: YES) is performed. Is started.
[0039]
That is, one document is taken out from the paper feed tray 1a and the conveyance is started (S5), and the size of the conveyed document is detected by the first conveyance of the conveyance path 2b (S6). As shown in b), the reversal of the transport direction is performed twice by the reversal control of the extra transport roller 4f (S7). When the document having been reversed twice in the transport direction passes through the reading unit 3 in the third transport along the transport path 2b, the document is read (S8), and the single-side reading process of the first document is performed. finish.
[0040]
On the other hand, if the single-sided reading button 13a is not pressed down and the start button 13c is not pressed down (S4: NO), the control unit 10 determines whether the double-sided reading button 13b is pressed down (S9). ). If the double-sided reading button 13b is not pressed down (S9: NO), the process returns to the step of determining whether the single-sided reading button 13a is pressed down (S2), and one of the single-sided reading button 13a, the double-sided reading button 13b, and the start button 13c is pressed down. Until it is processed, the process waits for the loop state.
[0041]
If the double-sided reading button 13b has been pressed down (S9: YES), the control unit 10 determines whether the start button 13c has been pressed down (S10), and if it has not been pressed down (S10: If no, the process goes into a loop waiting process until the press is performed. If the press is performed (S10: YES), one document is taken out of the paper feed tray 1a and transport is started (S11). The size of the conveyed document is detected by the first (first) conveyance on the conveyance path 2b (S12).
[0042]
After the detection, as shown in FIG. 4B, the first transport direction is reversed (S13), and one side (back side) of the original is read by the reading unit 3 in the second transport along the transport path 2b. (S14). After the reading, the second reversal of the transport direction is performed (S15), and in the third transport of the transport path 2b, the reading unit 3 reads the other surface (front surface) of the original (S16). The process of reading both sides of the original is completed. The reading process including reversal is also performed on the second and subsequent documents in the same manner as described above.
[0043]
In this manner, the image reading apparatus 1 of the present invention reliably performs single-sided reading or double-sided reading on a mixed original in response to the depression of the one-sided reading button 13a, the two-sided reading button 13b, or the start button 13c. In addition, by detecting the size of the original document during the first transport, the magnification can be recognized before reading by the reading unit 3, and the image processing can be performed according to the magnification at the time of reading. Accordingly, the document conveying speed can be appropriately changed.
[0044]
Note that the above-described reading processing has been described with respect to the case where the mixed reading button 13e (a reading receiving unit that receives a reading instruction of a plurality of documents having different sizes) is pressed down for the mixed original. When performing reading, the mixed reading button 13e is not pressed down, and the following reading is performed in accordance with the pressing of one of the single-sided reading button 13a, the double-sided reading button 13b, and the start button 13c in the non-mixed original reading mode. Processing is performed.
[0045]
In the non-mixed original reading mode, the original size can be detected by a sensor provided on the paper supply tray 1a in a state where the original bundle is set on the paper supply tray 1a. Does not detect the original size at the time of the first transport.
[0046]
When the single-sided reading button 13a and the start button 13c are depressed, and when only the start button 13c is depressed, a single-sided reading process of the document is performed, and the first side of the document is read by the first conveyance of the conveyance path 2b. When the document passes through the unit 3, a document is read. After the reading, the inverted document is discharged to the paper output tray 11b without performing the reversal control, the one-side reading process for the first document is completed, and the second and subsequent documents are read in the same manner as described above. Processing is performed.
[0047]
When the double-sided reading button 13b and the start button 13c are pressed down, a double-sided reading process of the original is performed, and the original is transported through the transport path 2b a total of three times by the reversal control twice, and then is transferred to the discharge tray 1b. Is discharged. Specifically, reading of the front side of the document is performed in the first transport on the transport path 2b, reading of the back side of the document is performed in the second transport, and discharge to the paper discharge tray 1b is performed in the third transport. Page order. In addition to the above-described processing, it is also possible to read the back surface of the original in the second transport in the third transport and read the front surface of the original in the third transport.
[0048]
The image reading device 1 according to the present invention can be appropriately applied as an image reading unit such as a copying device, a facsimile device, and a scanner device. Further, the image reading device according to the present invention may have the following configuration.
[0049]
That is, in an image reading apparatus having a plurality of image sensors arranged in the main scanning direction of a document and a reading unit for reading an image of the document conveyed in the sub-scanning direction based on an output signal of the image sensor, And a length detecting means for detecting the presence or absence of a passing document in order to detect the length which is the size of the document in the conveying direction. Reversing means for reversing the document, mixed reading reception means for receiving a mixed reading instruction of the original, and control means, wherein the control means is configured to perform the first reading operation when the mixed reading receiving means receives the mixed reading instruction. Detecting a width that is a size in a direction orthogonal to a document conveying direction based on an output signal of the image sensor, and detecting the length based on an output signal of the length detecting unit; At the time of the second and / or third paper passing after reversing the document conveyance direction, the reading unit may read the document image using the length and width detected during the first paper passing. Good.
[0050]
Further, when performing the single-sided reading, the control unit performs width detection at the time of the first sheet passing based on an output signal of the image sensor with respect to one side of the document, and performs the reading at the time of the second sheet passing. It is also possible to perform image reading on one side of the original using the length and width detected at the time of the first sheet passing, without performing reading by the copy unit at the time of the third reading.
[0051]
The apparatus further includes a duplex reading accepting unit that accepts a duplex reading instruction of the original, wherein the control unit, when the duplex reading accepting unit receives the duplex reading instruction, detects the width at the time of the first pass of the original. Based on the output signal of the image sensor on one side of the document, an image is read on the other side of the original using the length and width detected at the time of the first pass at the time of the second pass. At the time of the first reading, the image reading on one side of the document may be performed using the length and width detected at the time of the first sheet passing.
[0052]
【The invention's effect】
As described in detail above, according to the first aspect, by detecting the width size of the document based on the reading of the image sensor of the reading unit, the width sensor can be eliminated, and the space required for the width sensor can be reduced. The size can be reduced, and the structure required for the arrangement of the width sensor and the electrical connection can be simplified.
According to the second aspect, by performing control corresponding to single-sided reading, it is possible to perform control processing related to transport and reading corresponding to single-sided reading.
According to the third aspect, by receiving the instruction for double-sided reading, it is possible to perform control processing related to conveyance and reading corresponding to double-sided reading.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view of an image reading apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a transport unit according to the embodiment.
FIG. 3 is a block diagram of the image reading apparatus according to the embodiment;
FIG. 4A is a schematic diagram illustrating a first transport status of a transport unit, and FIG. 4B is a schematic diagram illustrating a reverse status of a transport direction by switchback control.
FIG. 5A is a schematic diagram illustrating a transport state after a first reversal, and FIG. 5B is a schematic diagram illustrating a transport state after a second reversal.
FIG. 6 is a flowchart illustrating a series of processes of the image reading apparatus.
[Explanation of symbols]
1 Image reading device
2 Transport section
2a Paper path
2b transport route
2c Paper ejection side path
2d inversion path
3 Reading unit
4f Extra transport roller
4g press transport roller
5 Length sensor
6 Reversing sensor
9 CCD
10 control unit
13 Operation section
13a Single-sided reading button
13b Double-sided reading button
13e Mixed reading button
G manuscript
Ga surface
Gb back side

Claims (3)

A reading unit that reads an image of a document that is conveyed in the sub-scanning direction by an imaging element that is arranged in the main scanning direction for reading the document and outputs an output signal related to the reading, and a document that passes through the reading unit An image reading apparatus comprising:
A length detecting means provided on the transport path for detecting the length of the document in the transport direction;
A reversal path that does not pass through the reading unit that leads from the downstream position in the conveyance direction to the upstream position from the reading unit in the conveyance path,
Reversing means for performing reversal conveyance of the document conveyed to the downstream position via the reversing path,
First, the length of the document conveyed along the conveyance path is detected based on the detection result of the length detection unit, and the width of the document in the direction perpendicular to the document conveyance direction is determined based on the output signal of each image sensor. Control for performing detection, control of reversal conveyance of the reversing means for the document conveyed to the downstream position, and detection length of the document conveyed on the conveyance path for the second and / or third time by the reading unit An image reading apparatus comprising: a control unit that controls reading according to the height and width. The control means includes:
2. A control for performing one-sided reading of a document without reading a document conveyed along the transport path for the second time and reading a document conveyed along the transport path for a third time. 5. The image reading device according to claim 1. The image forming apparatus further includes a double-sided reading reception unit that receives an instruction to read both sides of the document,
The control means includes:
3. The image reading apparatus according to claim 1, wherein when the double-sided reading reception unit receives a double-sided reading instruction, the image reading apparatus performs control to read a document conveyed on the conveyance path for the second and third times. 4. .

Images