JP4086364B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus that reads an image of a document being conveyed.
[0002]
[Prior art]
Conventionally, an image forming apparatus that reads an image of a document and forms the read image on a transfer material (hereinafter referred to as “paper”) has been used as a copying machine, a facsimile, a laser beam printer, or the like. .
[0003]
This type of image forming apparatus includes a scanner that reads an image of a document, and a feeding roller that continuously transports a plurality of documents, and is conveyed to the image reading position by the feeding roller. The original stopped at this point is read by scanning the scanner (hereinafter, the method of moving the scanner and reading the image with the original stopped is referred to as “fixed reading method”). .
[0004]
However, when image reading is continuously performed using such a fixed reading method, even if image reading is completed, the original that has been read is not removed and the next original must be transported to the image reading position. Since the next image reading could not be started, and the time required to replace the original was required, the time from the end of the image reading to the start of the next image reading became longer, resulting in poor work efficiency.
[0005]
In this case, there is a method of increasing the document conveying speed in order to increase the work efficiency, but there are problems that the document is damaged and the conveying sound becomes loud.
[0006]
As a method of solving such a problem, there is a method of reading an image by moving an original while the scanner is stopped (hereinafter referred to as “flow reading method”). According to this flow reading method, the document can be exchanged while the image is read, and the time from the end of the image reading to the start of the next image reading can be shortened to improve the work efficiency. Further, it is not necessary to increase the document conveyance speed unlike the fixed reading method, and there is no problem that the document is damaged or the conveyance sound is loud.
[0007]
[Problems to be solved by the invention]
By the way, in such a flow reading method, in order to improve the accuracy of image reading, the document conveyance speed during image reading must be constant.
[0008]
In order to make the document conveyance speed constant in this way, there is a method of lengthening the document conveyance path, but there is a problem that the apparatus becomes large.
[0009]
Also, in order to perform image reading on large and small size documents, the length of the document transport path is set according to the small size document (the length at which the transport speed is constant when a small size document is transported). In the case of a large-size document, there is a problem that the conveyance speed is not constant and the image reading accuracy is inferior. Conversely, if you set the transport path length of a document along with a large document (set the transport speed to be constant when a large document is transported), the small document will be transported. In this case, although the conveyance speed is constant, there is a problem that the conveyance path length is too long and the time from the end of the image reading to the start of the next image reading becomes long, resulting in poor work efficiency.
[0010]
SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus with good image reading accuracy.
[0011]
Another object of the present invention is to provide an image forming apparatus that is small in size and has good image reading accuracy.
[0012]
Another object of the present invention is to provide an image forming apparatus that improves the image reading accuracy of a large-size document and increases the work efficiency of a small-size document when reading images of documents of different sizes. To do.
[0013]
[Means for Solving the Problems]
The present invention has been made in view of the above circumstances, and is provided with a first conveying unit that continuously conveys a plurality of originals, and a downstream side of the first conveying unit in the original conveying direction. A second conveying means for further conveying the original conveyed by the first conveying means, and an original conveyed by the second conveying means in a state of being stopped at a position facing the second conveying means In an image forming apparatus comprising: an image reading unit that reads
The distance from the stop position of the image reading unit to the first conveying unit is set to be longer than the length in the document conveying direction, and the image reading unit is engaged with the first conveying unit. Read the image of the original that is unloaded and being conveyed by the second conveying means,
The first transport unit transports a document subsequent to the document being scanned while the image scanning unit is scanning an image, and the document while the image scanning unit is not scanning an image. And the engagement with the document is released.
[0014]
Note that, based on the above configuration, when the first transport unit and the second transport unit transport a plurality of documents continuously, the image reading unit stopped at a position facing the second transport unit is The image of the original conveyed by the second conveying unit is read. Here, since the first conveying unit conveys a document subsequent to the document being image-read while the image reading unit is performing image reading, the first conveying unit performs the next operation after the end of image reading. Work time can be improved by shortening the time required to start image reading. The distance from the stop position of the image reading unit to the first conveying unit is set to be longer than the length in the document conveying direction, and the first conveying unit includes the image reading unit. However, while the image is not being read, the conveyance of the document is terminated and the engagement with the document is released. Accordingly, the document and the first conveying unit are not disengaged while the image reading unit is reading an image, and the document conveying speed during image reading can be kept constant.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
First, an embodiment of the present invention will be described with reference to FIGS.
<Description of overall configuration of image forming apparatus>
FIG. 1 is a cross-sectional view showing the overall configuration of an image forming apparatus G according to the present invention. A main body 1 of this image forming apparatus G (hereinafter referred to as “apparatus main body 1”) is a document at an image reading position. An image input unit (hereinafter referred to as “reader unit”) 200 for optically reading the image information of the image, an image output unit (hereinafter referred to as “printer unit”) 300 for printing the read image on a predetermined sheet, An automatic document feeder (hereinafter referred to as “ADF”) that automatically and sequentially conveys a document to the image reading position and reverses the front and back of the document that has been conveyed to the position is provided above the apparatus body 1. 2) is arranged.
<Description of Reader Unit 200>
Among them, the reader unit 200 has a platen 3 on which an upper surface of the apparatus main body 1 is formed and on which a document is placed, and below the platen 3 (that is, a wide belt 7 as a second conveying unit described later). A scanner 204 serving as an image reading unit is disposed at a position facing the head. The scanner 204 includes a lamp 202 and a mirror 203, and irradiates light on the original conveyed on the platen 3 to read an image of the original.
[0017]
The scanner 204 is configured to be moved along the platen 3 by a motor such as a well-known stepping motor. A mode in which the scanner 204 is moved while the document is stopped on the platen (hereinafter referred to as an image reading mode). , “Fixed reading mode”) and a mode in which an image is read by moving the document while the scanner 204 is stopped at a predetermined position (hereinafter referred to as “flowing reading mode”) can be realized. ing. Further, in this flow-reading mode, the stop position of the scanner 204 can be changed according to the size of the document by controlling the driving of the stepping motor or by providing a mechanical stopper (details). Will be described later). That is, in this flow reading mode, the stepping motor and the mechanical stopper function as reading position changing means for changing the stop position of the scanner 204.
[0018]
The reader unit 200 includes mirrors 205 and 206, a lens 207, an image sensor 208, and the like, and is configured to optically read image information recorded on a document, photoelectrically convert it, and read it as image data. ing.
<Description of Printer Unit 300>
As shown in FIG. 2, the printer unit 300 includes an image forming unit 301 that prints an image read by the reader unit 200 on a sheet, and a sheet conveyance system 302 that conveys the sheet.
[0019]
Among these, the image forming unit 301 includes a photosensitive drum 112 that is rotatably supported and is rotated in a clockwise direction by a driving unit (not shown). A primary charging device 113 that charges the surface of the drum 112 to a uniform potential, a developing device 114 that stores toner and uses an electrostatic latent image formed on the photosensitive drum 112 as a toner image, and the toner image A transfer charger 115 that transfers to a sheet, a separation charger 116 that separates the sheet from the photosensitive drum 112, and the like are sequentially arranged.
[0020]
Next, the paper transport system 302 will be described.
[0021]
On the side of the apparatus main body 1, cassettes 100 and 102 for storing sheets, a sheet stacking apparatus 108, and the like are arranged. The cassettes 100 and 102 and the paper stacking device 108 have separation claws (not shown) as is well known, and feed rollers 101, 103, and 109 are located at positions where they contact the stacked paper. Are arranged respectively. The sheets stored in the cassettes 100 and 102 and the sheet stacking device 108 are discharged one by one by the action of the separation claw and the feeding rollers 101, 103, and 109. The paper stacking device 108 includes a middle plate 108a for loading paper. The middle plate 108a is configured to be moved up and down by a motor or the like so that the feeding roller 109 and the paper always come into contact with each other. Yes. Further, a transport roller 110 for transporting the paper is disposed in the vicinity (upper left) of the feed roller 109.
[0022]
Further, a registration roller 106 is disposed between the cassettes 100 and 102 and the paper stacking device 108 and the above-described photosensitive drum 112, and the paper conveyed from the cassettes 100 and 102 or the paper stacking device 108 is photosensitive. The drum 112 is conveyed in synchronization with the rotation of the drum 112.
[0023]
A conveyance belt 117 for conveying the paper is disposed on the lower left side of the photosensitive drum 112, and a fixing device 118 for fixing the toner image transferred to the paper is disposed on the downstream side. Has been. Further, a conveying roller 119 and a discharge roller 121 are arranged on the downstream side of the fixing device 118, and the sheet after the fixing is discharged to the outside.
[0024]
On the other hand, between the transport roller 119 and the discharge roller 121, the paper transport path is branched downward, and the branched transport path enables the paper to be transported again to the registration roller 106 side. Thus, so-called double-sided copying (a mode in which images are formed on both sides of a sheet) and multiple copying (a mode in which an image is formed by superimposing images on one side of a sheet) are possible.
[0025]
In other words, the flapper 120 is arranged at the branching portion, and the conveyance path is switched. A transport roller 201, a transport belt 202, a transport belt 204, and a transport roller 205 for transporting paper are disposed on the transport path branched downward, and an intermediate tray on which paper is temporarily stacked. 200 is arranged. Note that a flapper 203 for switching the transport path is disposed between the transport belt 202 and the transport belt 204. By switching the flapper 203, the paper is transported via the path 206 during double-sided copying, and is placed on the intermediate tray 200 with the image side up. Further, at the time of multiple copying, the sheet is conveyed via the path 207 and is placed on the intermediate tray 200 with the image surface facing down.
[0026]
Thus, the sheets stacked on the intermediate tray 200 are separated and conveyed one by one from below by the action of the auxiliary rollers 209 and 210 and the forward / reverse separating roller pair 211, and the separated sheets are conveyed by the conveying roller 213. , 214, 215 and the conveyance roller 110 are conveyed to the image forming unit 301. Then, the second image formation is performed in the image forming unit 301, and the sheet on which the image is formed is conveyed again to the fixing device 118 by the conveyance belt 117, and externally by the conveyance roller 119 and the discharge roller 121. It is supposed to be discharged.
[0027]
By the way, a sorter 122 for storing discharged paper is disposed on the side of the apparatus main body 1 (on the side on which the discharge roller 121 is disposed). The sorter 122 includes a non-sort tray 122a and a sort bin tray 122b. When the paper is not sorted, the paper is discharged to the non-sort tray 122a by the non-sort tray discharge roller 122c, and the paper is sorted. The paper is discharged to the sort bin tray 122b by the sort bin tray discharge roller 122d.
[0028]
For example, when a plurality of double-sided copies of a single-sided original (an original on which images are formed on both sides), the image forming apparatus G performs single-sided copying for the set number of copies, and during that time, it is placed on the intermediate tray 200. Is loaded with sheets that are copied on one side. When the single-sided copying for the set number of copies is completed, the original is reversed and images are sequentially formed on the sheets stacked on the intermediate tray 200. The sheets that are copied on both sides in this way are sorted by the sorter 122.
[0029]
There is also a method of creating only one set of copies each time the document is made one round by ADF2. According to this method, even when a plurality of copies are created, a copy group with the same page order is obtained in order, so that the necessary number of copies can be obtained by sorting without a sorter. When making a double-sided copy with this method, scan both sides of a single document, copy and eject it on both sides of the paper, and then do the same for both sides of the next document. If it is repeated again, a divided double-sided copy group is obtained.
[0030]
Instead of such a sorter 122, a discharge tray having no sorting mechanism may be used.
<Description of ADF2>
Next, the structure of ADF 2 will be described.
<Description of document tray>
FIG. 3 is a detailed sectional view showing the structure of the ADF. The ADF 2 has a document tray 4 on which a large number of documents are stacked. Note that a pair of width direction restricting plates (not shown) are slidably disposed in the document tray 4 in the width direction of the document, and the width direction of the documents stacked is regulated by these width direction restricting plates. As a result, stability at the time of document feeding is ensured.
[0031]
Further, a stopper 21 is rotatably supported at the left end portion of the document tray 4, and the stopper 21 stands on the tray to prevent the document from being fed (solid line position in the figure). The position (chain line position in the figure) that is retracted and does not hinder the feeding is selectively taken.
<Description of each roller and document transport path>
Next, the rollers disposed in the ADF 2 and the conveyance path through which the document is conveyed will be described with reference to FIGS.
[0032]
Here, FIG. 4 is a diagram showing the structure of the paper feed roller 5 and the like disposed at the left end of the document tray 4, its operation, and the maximum rising position of the paper feed roller 5. It is a figure which shows the maximum descent | fall position. FIG. 7 is a plan view showing the structure of the paper feed roller 5 and the like.
[0033]
As described in detail in FIG. 4, a swing arm 53 that swings about the point c1 is disposed at the left end of the document tray 4 described above. It is supported rotatably. The paper feed roller 5 is configured to sequentially carry out the originals stacked on the original tray 4 based on rotation driven by a separation motor 100 described later. As shown in detail in FIG. 6 (a), the swing arm 53 has a through hole 53a formed in an arc shape (details will be described below). Also, as shown in FIG. 7, a plurality of paper feed rollers 5 are arranged along the width direction of the original so as to face the stacked originals.
[0034]
Further, an elevating arm 51 is disposed so as to swing around the above-described point c1, and this elevating arm 51 is configured to be movable from the position of FIG. 4 to the position of FIG. The elevating arm 51 has support plates 51a and 51b arranged with a predetermined gap in parallel with the paper surface, and positioning pins 51c are caulked and fixed to these support plates 51a and 51b (FIG. 6). (See (c)). The positioning pin 51c is inserted into the above-described through-hole 53a so that the lifting arm 51 is engaged with the swinging arm 53, and the swinging arm 53 is moved based on the swinging of the lifting arm 51. Is made to swing. Further, positioning pins 51e are caulked and fixed to the above-described support plates 51a and 51b (details will be described below).
[0035]
On the other hand, a separation upper guide plate 52 is disposed so as to swing about the point c1 (see FIG. 6B), and a separation lower guide 59 is disposed below the separation guide 59 so as to be continuous with the document tray 4. ing. The lower separation guide plate 59 is disposed below the document carried out by the paper feed roller 5 to guide the lower surface of the document, and the upper separation guide plate 52 is disposed above the document to be carried out. The upper surface of the document is guided.
[0036]
By the way, as described in detail in FIG. 4, the positioning pin 51e of the lifting arm 51 described above supports the separation upper guide plate 52 from the lower side when the document is set (upward position) so as to increase the space between the positioning tray 51e and the document tray 4. It is open.
[0037]
Since the paper feed roller 5 is lowered until it abuts on the original at the start of paper supply (details will be described later), the paper feed roller 5 bounces as is well known when landing on the original P. When a plurality of paper feed rollers 5 are arranged in the width direction of the document (see FIG. 7), the pressure balance between the plurality of paper feed rollers 5,. When the feeding operation is started, the possibility of causing the skew of the document increases.
[0038]
However, in the present embodiment, each of the feeding rollers 5 has an independent suspension configuration and is easily equalized to the original P. Therefore, it is possible to improve the paper feeding performance.
[0039]
On the other hand, the separation conveyance roller 8 is rotatably supported at the rotation center c1 of the lifting arm 51 described above, and a well-known separation belt 6 is rotatably disposed below the roller 8. These separation / conveying roller 8 and separation belt 6 are rotationally driven in the direction of the arrow by a separation motor 100 described later, and when a plurality of documents are fed simultaneously by the sheet feeding roller 5, the separation / conveying roller 8 is One original is conveyed downstream, and the separation belt 6 returns the other original to the original tray 4 side. The separation conveying roller 8 and the separation belt 6 constitute a separation section S, which separates these originals. The separation conveyance roller 8 has a one-way mechanism, and reduces the conveyance load when the document is pulled out from the separation unit S by the first feeding roller 16 (details will be described below).
[0040]
Further, as shown in FIG. 42, the first feeding roller 16 is rotatably supported on the downstream side (the left side in the drawing) of the separation unit S, and the document fed from the separation unit S is further downstream. It is designed to be transported. Note that a document conveyance path between the separation unit S and the first feeding roller 16 is indicated by a symbol (A).
[0041]
Further, the document conveying path (b) on the downstream side of the first feeding roller 16 is formed to bend downward and to the left, and the second feeding as a first conveying unit is formed in the conveying path (b). A feed roller 9 is rotatably supported. The second feeding roller 9 is configured to sequentially convey a plurality of documents to the downstream side. The second feeding roller 9 is configured to stop driving while the document is conveyed by the first feeding roller 16, thereby forming a loop in the document to form the document. The skew is prevented.
[0042]
Furthermore, a document conveyance path (c) is formed downstream of the second feeding roller 9 in the document conveyance direction (that is, from the lower side of the second feeding roller 9 to the upper left side of the platen 3). A drive roller 36 is rotatably supported on the upper left side of the platen 3. Further, a turn roller 37 that is also rotatably supported is disposed on the upper right side of the platen 3 (see FIG. 1), and a wide belt 7 is wound around these rollers 36 and 37 to form a second roller. Conveying means is configured. The wide belt 7 has a width equal to or greater than that of the original, and is disposed along the platen 3 to form an original conveyance path (d) together with the platen 3. Further, the wide belt 7 is driven to rotate in both forward and reverse directions by the driving roller 36, so that the original conveyed by the second feeding roller 9 is further conveyed in the same direction, or conversely the second feeding. The feed roller 9 is fed back.
[0043]
In other words, in the present embodiment, the document conveyance paths (A), (B), and (C) are curved from the document tray 4 to the platen 3, and the sheet feeding roller 5, the separation unit S, and the first feeding are formed. By the functions of the roller 16 and the second feeding roller 9, the originals P on the original tray are sequentially separated and conveyed to the platen 3.
[0044]
By the way, the above-described document conveyance path (C) is formed so as to bend from the second feeding roller 9 to the lower right toward the platen 3, but from the second feeding roller 9 to the lower left, it is reversely fed. The feeding path (chi) is formed in a curved shape, and the first reversing roller 17 is rotatably supported at the end of the feeding path (chi). The reverse feeding path (H) and the document conveying path (d) described above are communicated with each other by a reverse feeding / discharging path (e).
[0045]
The reverse feed path (f) from the first reverse roller 17 extends to the upper left, and the second reverse roller 18 is rotatably supported at the end of the feed path (f). Yes. Further, the reverse feed path (f) is branched into two reverse feed paths (Li) (G) above the second reverse roller 18, and the reverse feed path (Li) is the second reverse roller 18. The reverse feed path (g) extends toward the upper right and extends toward the original transport path (b), and communicates the reverse feed path (f) and the original transport path (b). That is, in the present embodiment, the reverse feeding path (e) (f) (f) (g) (g) is connected to the document transport path (d), ie, the document reading position. Further, the first reversing roller 17 and the second reversing roller 18 perform the reversal of the original by conveying the original along the reverse feeding path (f) (re) (g).
[0046]
In the present embodiment, when the document is reversed (pre-reversal processing) before being conveyed to the platen 3,
(B) → (b) → (h) → (f) → (re) → (e) → (d)
The document is conveyed in this order (details will be described later).
[0047]
Further, when the document is reversed to the front and back (reversing process) after the document is already conveyed to the platen 3 and the reading of the document is finished,
(E) → (f) → (g) → (c) → (d)
The document is conveyed in this order (details will be described later).
[0048]
On the other hand, a document discharge path (nu) and a sheet discharge tray 10 are arranged on the right side of the wide belt 7 described above, and a sheet discharge roller 12 and a conveyance roller 19 are provided in the document discharge path (nu). The document P on the platen 3 for which image reading has been completed is discharged to the paper discharge tray 10.
[0049]
On the other hand, an open / close-type manual document tray 14 is disposed above the paper discharge tray 10, and a manual paper feed roller 13 is disposed at the left end of the tray 14. And the conveyance roller 19 described above, the document P (one document) set on the manual document tray 14 is fed to the manual conveyance path (L).
[0050]
Further, a manual registration roller 11 is provided in the manual conveyance path (L), and is configured to convey the fed document to the platen 3. The registration roller 11 is configured to stop driving while the document is being conveyed, as with the second feeding roller 9 described above, thereby forming a loop in the document and The skew of the original is prevented.
[0051]
On the other hand, a manual shutter 28 is rotatably supported on the downstream side of the manual feed roller 13, and the manual shutter 28 closes the manual conveyance path (L) and is set on the document (manual document tray 14). It is configured to selectively take a position (a chain line position in the figure) where feeding of the manual feed document is blocked and a position (a solid line position in the figure) where the feeding is prevented and is not hindered. This prevents the manual document set on the manual document tray 14 from entering the manual conveyance path (L) while the document whose image reading has been completed is being conveyed from the platen 3 to the paper discharge tray 10. . The manual feed roller 13 is driven to rotate while the manual feed shutter 28 prevents the document from being fed in this way, but the conveying force of the roller 13 causes the roller 13 and the document to slip. Is set low.
<Description of flapper>
Next, the flapper disposed on each of the document conveying paths described above will be described with reference to FIG.
[0052]
A reversing paper feeding flapper 22 is swingably disposed at the junction between the original conveying path (c), the reversing feeding path (h), and the flapper 22 is swung to a solid line position in the drawing. The document feed path (C) is closed and the reverse feed path (C) is opened, or the reverse feed path (C) is closed by swinging to the position of the chain line in the figure and the document feed path (C). Is configured to open.
[0053]
A reversing flapper 23 is slidably disposed at a junction between the reversing feeding path (re) and the reversing feeding path (g) (on the downstream side in the transport direction of the second reversing roller 18). 23 is swung to the position of the solid line in the figure to close the reverse feeding path (g) and opens the reverse feeding path (re), or is swung to the position of the chain line in the figure to reverse the feeding path. (Re) is closed and the reverse feed path (g) is opened.
[0054]
Furthermore, a unidirectional flapper 24 (mylar or the like is affixed) is slidably disposed at the junction of the reverse feed path (h) and the reverse feed / discharge path (e). In addition to serving as a guide for transporting the original P from the reverse feeding path (h) to the reverse feeding path (f), the original P is fed from the reverse feeding path (g) to (f). ) Is conveyed to the platen 3 to prevent the original P from going up to the reverse feeding path (H).
[0055]
Further, on the platen 3 side of the reverse supply / discharge path (e), a supply / discharge flapper 25 interlocked with the reverse feed flapper 22 is disposed so as to be swingable. When transported from the discharge path (e) to the platen 3, it is swung to the position of the solid line in the figure to prevent the leading edge of the document P entering the platen 3 from colliding with the end of the platen 3. When the document P is conveyed from 3 to the reverse feeding / discharging path (e), the document P is swung to the position of the chain line in the figure so that the document P is smoothly conveyed.
[0056]
A paper discharge flapper 26 is swingably disposed between the right end of the platen 3 and the manual registration roller 11, and the flapper 26 transports the document P from the manual transport path (L) to the platen 3. Is prevented from colliding with the end of the platen 3 that is swung to the position of the solid line in the figure and entering the platen 3, and the original P is discharged from the platen 3 to the original discharge path (n). In this case, the original P is smoothly ejected by swinging to the position of the chain line in the figure.
[0057]
Further, a one-way manual flapper 27 is slidably disposed at the junction of the original discharge path (nu) and the manual feed path (le). The flapper 27 is discharged from the platen 3 to the discharge tray 10. This prevents the original P to be entered from entering the manual feed path (L).
<Description of drive system>
Next, a drive system for driving the above-described rollers and flappers will be described with reference to FIG.
[0058]
The separation conveyance roller 8, the separation belt 6, and the paper feed roller 5 described above are configured to be rotated by a PLL brushed DC brush motor (hereinafter referred to as “separation motor”) 100. A separation clutch 106 is interposed between the separation motor 100 and the separation conveyance roller 8 and the separation belt 6 and the paper feed roller 5, and drive transmission is turned on / off by the clutch 106. ing. A clock plate 100a having a plurality of slits is fixed to the motor shaft of the separation motor 100, and a separation clock sensor 100b, which is a transmissive optical sensor, is disposed at a position facing the clock plate 100a. Has been. The separated clock sensor 100b generates a clock pulse proportional to the motor speed when the separated motor 100 rotates. That is, the document feed amount by the separation motor 100 can be detected by counting the clock pulses. A separation sensor 30 (to be described later) detects the passage of the document, and simultaneously starts counting clock pulses from the separation clock sensor 100b, thereby detecting the document transport position.
[0059]
The second feeding roller 9, the first reversing roller 17, and the second reversing roller 18 are configured to be rotationally driven by a stepping motor (hereinafter referred to as “conveying motor”) 101 that can rotate forward and backward. Yes. A clock plate 101a having a plurality of slits is fixed to the driven roller shaft of the second feed roller 9, and a reversing clock that is a transmissive optical sensor is provided at a position facing the clock plate 101a. A sensor 101b is arranged. The reverse clock sensor 101b generates a clock pulse proportional to the rotational speed of the driven roller. When slip occurs while the original P is being transported by the second feeding roller 9, the slip amount can be measured from the number of clock pulses and the number of driving clocks of the transport motor 101.
[0060]
Further, the above-described drive roller 36 (that is, the wide belt 7) is rotationally driven by a stepping motor (hereinafter referred to as “belt motor”) 102 capable of rotating in the forward and reverse directions. The belt motor 102 can also detect the motor rotation speed by a clock plate having a plurality of slits and a clock sensor which is a transmissive optical sensor.
[0061]
Here, the rotation of the drive roller 36 is transmitted to the turn roller 37 by the wide belt 7, but the drive is transmitted from the turn roller 37 to the manual registration roller 11, and the document conveying speed and the manual registration on the platen 3 are transmitted. The conveying speed of the roller 11 is made equal.
[0062]
The lifting arm 51 described above is configured to be swung by a stepping motor (hereinafter referred to as a “swinging motor”) 103 capable of forward and reverse. This swing motor can also detect the motor rotation speed by a clock plate having a plurality of slits and a clock sensor which is a transmissive optical sensor.
[0063]
Further, the paper discharge roller 12 and the manual paper supply roller 13 are configured to be rotationally driven by an FG servo-controlled DC motor (hereinafter referred to as “paper discharge motor”) 104. A clock plate 104a having a plurality of slits is fixed to the motor shaft of the paper discharge motor 104, and a paper discharge clock sensor 104b, which is a transmission type optical sensor, is located at a position facing the clock plate 104a. Is arranged. The paper discharge clock sensor 104b generates a clock pulse proportional to the rotational speed of the motor when the paper discharge motor 104 rotates.
[0064]
Furthermore, the stopper 21 described above is driven by a stopper solenoid 105. Specifically, the stopper 21 is in a solid line position in the figure when the stopper solenoid 105 is off, and swings to a chain line position in the figure when the solenoid 105 is on. It has come to be.
[0065]
Further, the reverse feed flapper 22 and the supply / discharge flapper 25 are driven by a path switching solenoid 107. Specifically, each of the reverse feed flapper 22 and the supply / discharge flapper 25 is in a solid line position in the figure when the solenoid 107 is off, Is swung to the position of the chain line.
[0066]
Further, the reverse flapper 23 is driven by a reverse flapper solenoid 108. Specifically, when the solenoid 108 is off, the reverse flapper 23 is in the solid line position in the figure, and when the solenoid 108 is on, the reverse flapper 23 is swung to the cut line position in the figure. It is like that.
[0067]
Further, the paper discharge flapper 26 and the manual shutter 28 are driven by a paper discharge flapper solenoid 109. Specifically, when the solenoid 109 is off, it is in the chain line position in the figure, and when the solenoid 109 is on, the solid line in the figure. It can be swung to a position.
<Description of each sensor>
Next, each sensor will be described.
[0068]
As described in detail in FIG. 4, the lifting arm 51 described above has a lifting arm flag 51d, and a position corresponding to the flag 51d (above the separation portion S) is a transmissive optical sensor. A paper roller home sensor 45 is provided. When the lift arm 51 is raised and the lift arm flag 51d blocks the sensor optical path of the paper feed roller home sensor 45 as shown in the drawing, it can be detected that the lift arm 51 is in the standby position that is the home position. It has become.
[0069]
Further, as shown in detail in FIG. 4, a swing arm flag 54 is formed on a part of the swing arm 53, and the lift arm 51 detects the relative position of the swing arm 53 and the lift arm 51. A swing position sensor 46 is attached. As shown in FIG. 16, when the paper feed roller 5 comes into contact with the uppermost document, the swing position sensor 46 is shielded by the swing arm flag 54 and outputs an ON signal. Based on the detection result of the swing position sensor 46, the paper feed roller 5 is moved to the contact position and the separation position.
[0070]
Further, as shown in FIG. 3, a document set detection sensor 40 which is a transmission type optical sensor is provided in the vicinity of the upstream portion of the stopper 21 and detects that the document P is set on the document tray 4. It is like that. When the document set detection sensor 40 detects that the document P is set on the document tray 4, the paper feed roller 5 is moved to the contact position.
[0071]
Furthermore, a document trailing edge detection sensor (document size detection means) 41, which is a reflection type optical sensor, is provided in the middle of the document tray 4 (at a distance of 225 mm from the stopper 21). The length in the transport direction is detected. That is, the document trailing edge detection sensor 41 can detect whether a large-size document or a half-size document is set. Based on the size information from the document trailing edge detection sensor 41, the stop position of the scanner 204 in the flow reading mode is changed to a position R2 or R3 described later by a stepping motor or the like (reading position changing means). It has become.
[0072]
A final document detection sensor 43, which is a reflection type optical sensor, is provided between the document set detection sensor 40 and the trailing edge detection sensor 41, and determines whether or not the document being conveyed is the final document. It can be done.
[0073]
Further, a paper width detection sensor 44 is provided below the document tray 4 and detects the length in the width direction of the document P set on the document tray 4 based on detecting the position of the width direction regulating plate 33. It is supposed to be.
[0074]
Further, a separation sensor 30 that is a transmission type optical sensor is provided in the document conveyance path between the separation conveyance roller 8 and the first feeding roller 16, and the document conveyed by the separation conveyance roller 8. The passage of P is detected.
[0075]
In addition, a skew detection sensor 31 that is also a transmission type optical sensor is provided at the same position as the separation sensor 30 in the transport direction and at a predetermined distance in the thrust direction (the width direction of the document). Along with the sensor 30, the skew amount of the fed document can be detected.
[0076]
In addition, a mixed loading detection sensor 32 that detects the document P by flag movement is provided on the downstream side of the first feeding roller 16 and in the vicinity of the roller 16, and has a different size in combination with the sensor on the document tray 4. It is possible to detect that the original document is set on the document tray 4 while the document is being conveyed.
[0077]
Further, a paper feed sensor 35, which is a transmission type optical sensor, is disposed on the upstream side of the second feed roller 9 and in the vicinity of the roller 9, and the document transport path (a) (b) (c) ) And the reverse feeding path (g), the front end and the rear end of the document P conveyed are detected.
[0078]
Further, a registration sensor 39, which is also a transmission type optical sensor, is disposed on the downstream side of the feeding roller 9, and the stop position of the document P is controlled by detecting the rear end of the document P. It has become.
[0079]
A reversing sensor 38, which is a transmissive optical sensor, is disposed in the reversing supply / discharge path (e), and detects the document P discharged from the platen 3 or the document P entering the platen 3. It is like that.
[0080]
Further, a reverse detection sensor 33 for detecting the document P by flag movement is provided in the reverse feeding path (Li), and the original P is guided to the reverse feeding path (Li) by switching the reverse flapper 23. It comes to detect things.
[0081]
Further, a manual registration sensor 34, which is a transmission type optical sensor, is provided in the vicinity of the downstream of the manual registration roller 11 in the paper discharge direction, and detects a document from the manual conveyance path (L) and from the platen 3. A document P discharged to the document discharge path (n) is detected.
[0082]
Further, a manual document detection sensor 370 for detecting the document P by moving the flag is provided on the manual document tray 14 side of the manual feed roller 13 so as to detect that the document is set on the manual document tray 14. It has become.
<Positional relationship between document and scanner during image reading>
Next, the positional relationship between the document and the scanner during image reading will be described with reference to FIGS. 8 and 9 are diagrams showing the positional relationship between the document and the scanner at the time of image reading.
[0083]
In the image forming apparatus G, as described above, the fixed reading mode (the mode in which the scanner 204 is moved while the document is stopped on the platen) and the flow reading mode (the scanner 204 is changed). The mode in which the document is moved while it is stopped at a predetermined position can be selected. The reference symbol R1 in the figure indicates the home position (in other words, the home position of the scanner 204 in the fixed reading mode). The rear end position of the document placed at the image reading position is shown. This fixed reading mode is implemented in the double-sided document mode.
[0084]
Further, as described above, the stop position of the scanner 204 can be changed in accordance with the size of the document in the flow scanning mode. Reference numeral R2 indicates the stop position of the scanner 204 in the half-size single-sided document transport mode. (That is, the position of the leading edge of the document at the moment when image reading is started; hereinafter referred to as “second image destination R2”). Reference numeral R3 denotes a large-size single-sided document conveyance mode and a half-size document in a vertical direction. A stop position of the scanner 204 in the case of feeding (that is, the position of the leading edge of the document at the moment when the image reading is started, hereinafter referred to as “third image destination R3”) is shown.
[0085]
Further, in FIG. 8, reference numeral L <b> 1 indicates the distance from the nip point of the second feeding roller 9 to the first image tip R <b> 1, and reference symbol L <b> 2 indicates the second image tip R <b> 2 from the nip point of the second feeding roller 9. The symbol L3 indicates the distance from the nip point of the second feeding roller 9 to the third image tip R3. In FIG. 9, a symbol L4 indicates a distance between the half-size leading edge stopped on the platen before the image reading and the first drawing tip R1, and a symbol L5 indicates the stopped half-sized leading edge and the first tip. The distance from the second image end R2 is indicated. Reference numeral L6 indicates the distance (inter-paper distance) between the trailing edge of the preceding document and the trailing edge of the succeeding document. Reference numeral L7 indicates the distance from the first image destination R1 to the manual registration roller 11. Indicates the distance.
[0086]
In this embodiment, the distance L2 (the distance L2 from the nip point of the second feeding roller 9 to the second image tip R2) is the length in the document transport direction (in this case, the half-size document (The length in the conveyance direction) is set to be longer than the length of the document, and the trailing edge of the document has already come out of the second feeding roller 9 before the image reading. The feed roller 9 is prevented from coming off (details will be described later). Further, the distance L3 (the distance L3 from the nip point of the second feeding roller 9 to the third image tip R2) is longer than the length in the document transport direction (in this case, the length in the transport direction of the large size document). Is set so that the trailing edge of the document does not come off from the second feeding roller 9 during image reading (details will be described later).
[0087]
Further, in the flow-reading mode, the scanner 204 is stopped at the position R2 or R3, but the stop position can be slightly changed according to the size signal from the ADF 2.
[0088]
On the other hand, in this embodiment,
[0089]
[Formula 1]
L7 <L4 + 2 × L6 + Lph
Lph: Length in the conveyance direction of half-size documents
The distances L4, L6, and L7 are set so as to satisfy the relationship. Therefore, when two documents (documents Pn and Pn-1 in the figure) are stopped on the platen 3, the trailing edge of the preceding document (Pn-2) passes through the nip of the manual registration roller 11. ing.
<Description of control circuit>
Next, the control circuit of the ADF 2 will be described with reference to FIG.
[0090]
FIG. 10 is a block diagram showing a circuit configuration of the control circuit of the present embodiment. The control circuit C is composed mainly of a microprocessor (hereinafter referred to as “CPU”) 201, and includes a RAM (not shown) backed up by a battery and a ROM (also not shown) in which control sequence software is stored. ). Reference numeral 202 denotes a communication IC for controlling data communication with the copying machine main body.
[0091]
The input port of the CPU 201 includes a separation sensor 30, a skew detection sensor 31, a mixed loading detection sensor 32, a reverse detection sensor 33, a manual registration sensor 34, a paper feed sensor 35, a reverse sensor 38, a manual document detection sensor 370, a registration Various sensors such as a sensor 39, a document set detection sensor 40, a document trailing edge detection sensor 41, a final document detection sensor 43, a paper width detection sensor 44, a paper feed roller home sensor 45, and a swing position sensor 46 are connected. It is used for monitoring the behavior of the document and the behavior of the movable load in the inside.
[0092]
On the other hand, motors 100,... Are connected to the output ports of the CPU 201 via drive circuits 203,.
[0093]
That is, the separation motor 100 (DC brush motor) described above is connected to the CPU 201 via the driver 203 and the controller 203a, and is driven and controlled by the driver 203 and the controller 203a. The controller 203a receives a reference clock, an on / off signal, and the like as a reference for the motor rotation speed from the CPU 201.
[0094]
Further, the transport motor 101 (stepping motor) is connected to the CPU 201 via a stepping motor driver 204 and is driven and controlled by the stepping motor driver 204. Further, the belt motor 102 (stepping motor) is connected to the CPU 201 via the stepping motor driver 205, and is driven at a constant current by the stepping motor driver 205. Each of the drivers 204,... Receives a phase excitation signal and a motor current control signal from the CPU 201.
[0095]
Furthermore, the swing motor 103 (stepping motor) is connected to the CPU 201 via a driver 206 and is driven at a constant voltage by the driver 206.
[0096]
The paper discharge motor 104 (DC brush motor) is connected to the CPU 201 via a driver 207 and an FG servo controller 207a, and is driven and controlled by the driver 207 and the FG servo controller 207a. It has become.
[0097]
Further, the stopper solenoid 105 is connected to the CPU 201 via the driver 208 and is driven and controlled by the driver 208.
[0098]
Furthermore, the separation clutch 106 is connected to the CPU 201 via the driver 209 and is driven and controlled by the driver 209.
[0099]
The path switching solenoid 107 is connected to the CPU 201 via the driver 210 and is driven and controlled by the driver 210.
[0100]
Further, the reverse flapper solenoid 108 is connected to the CPU 201 via the driver 211, and is driven and controlled by the driver 211.
[0101]
Furthermore, the paper discharge flapper solenoid 109 is connected to the CPU 201 via a driver 212 and is driven and controlled by the driver 212.
[0102]
The operations of all the drivers 203 to 212 described above are controlled by a signal input to the CPU 201.
[0103]
Next, the operation of the present embodiment will be described.
[1] Outline of action
First, an outline of the operation of the present embodiment will be described with reference to FIG.
[0104]
When the document set detection sensor 40 detects that the document P is set on the document tray 4, and the operator presses the start key (copy key) on the operation unit of the apparatus main body 1, the operation starts (main1). .
[0105]
Next, the copy mode transmitted from the apparatus main body 1 is discriminated (main 2), and if it is the single-sided manuscript mode, it is discriminated whether or not the document trailing edge detection sensor 41 is turned off (main 3). Whether or not the document P is half-size or large-size can be detected by this determination. If the determination is affirmative (half-size), a series of copy processing is executed in a first flow reading mode to be described later, and the operation ends. If (main4, main9) is a negative determination (large size), a series of copying processes are executed in the second flow reading mode described later, and the operation is terminated (main5, main9).
[0106]
On the other hand, if the copy mode transmitted from the apparatus main body 1 is determined and it is the double-sided original mode (main 2), a series of copying processes are executed in the double-sided original mode and the operation is terminated (main 6, main 9).
[0107]
Further, when the operator sets a document on the manual document tray 14, the manual document detection sensor 370 outputs a signal. In this state, the operator presses a start key (copy key) on the operation unit of the apparatus main body 1. Then, a series of copying processes are executed in the manual feed mode, which will be described later, and the operation is finished (main 7, main 8, main 9).
[2] Single-sided document transport mode
First, the operation in the single-sided document conveyance mode will be described separately for the half-size single-sided document conveyance mode and the large-size single-sided document conveyance mode.
[2-1] Half-size single-sided document conveyance mode
First, an outline of the operation when a half-size single-sided original is conveyed will be described with reference to FIG.
[0108]
FIG. 12 is a flowchart showing the outline of the operation.
[0109]
When a half-size single-side original is conveyed, first, a pickup DOWN process (details will be described later) is performed, and the paper feed roller 5 is lowered and brought into contact with the original P1 (FIG. 12 draftmd1).
[0110]
Thereafter, a separation process (details will be described later) is executed to separate only the uppermost document P1 (FIG. 12 draft md2), and then a paper feed process is executed (FIG. 12 draft md3).
[0111]
Then, when the document P1 is conveyed to a predetermined position on the platen 3, a document flow reading process (first flow reading mode) is executed, and the document image is read while the scanner 204 of the apparatus body 1 is fixed at the predetermined position. Reading is performed (FIG. 12 draftmd4).
[0112]
Thereafter, it waits for the separation sensor 30 to detect the trailing edge of the original (FIG. 12 draft 5). When the detection is made, the original set detection sensor 40 determines whether or not the original being conveyed is the final original (FIG. 12). 12draftmd6).
[0113]
If it is not the final document, a paper discharge process (details will be described later) for discharging the original P1 onto the paper discharge tray 10 is performed (FIG. 12 draftmd8), and the above operations are repeated (FIG. 12draftmd2-draftmd6).
[0114]
If the document being transported is the final document, a paper discharge process is performed (FIG. 12 draft md7), and a pickup UP process (details will be described later) is performed to return the paper feed roller 5 to the upper limit position (FIG. 12 draft md9). Then, a series of processing is completed.
[0115]
Next, details of the operation when a half-size single-sided original is conveyed will be described with reference to FIGS.
[0116]
FIGS. 13 and 14 are schematic diagrams showing the flow of a document when a half-size single-sided document is conveyed, and FIG. 15 is a flowchart showing details of the operation when conveying a half-size single-sided document. .
[0117]
Normally, the sheet feeding roller 5 is retracted to a position (home position) above the separation upper guide plate 52 as shown in FIG. Can be set. When a document is set, the document set detection sensor 40 outputs a signal, and the swing motor 103 is driven based on the signal to move the paper feed roller 5 to the contact position. Whether or not the paper feed roller 5 has reached the contact position is determined based on a signal from the swing position sensor 46, but when it is determined that the paper feed roller 5 has reached the contact position. The drive of the swing motor 103 is stopped.
[0118]
In the following description, it is assumed that the documents stacked on the document tray 4 are “document P1”, “document P2”, and “document P3” in order from the top. If the document order is not specified, “document P” is set.
[0119]
Now, when the operator inputs a copy condition at the operation unit of the image forming apparatus and presses a start key (copy key), the paper size detection sensor 44 detects the document size.
[0120]
Although the path switching solenoid 107 is turned off and the reverse feed flapper 22 is held at the position shown by the solid line in FIG. 3, the original transport path (C) is closed and the reverse feed path (H) is opened. In the mode, the path switching solenoid 107 is controlled to be on (FIG. 15 ent1), the reverse feed flapper 22 is moved to the chain line position shown in FIG. 3, the reverse feed path (f) is closed, and the document transport path (c). Is released. Further, the stopper 21 is moved to the chain line position in FIG. 3 by the stopper solenoid 105, and the document conveyance path (A) is opened.
[0121]
Next, the separation motor 100, the conveyance motor 101, and the belt motor 102 are activated (ent2 in FIG. 15), and the sheet feeding roller 5, the separation belt 6, the separation conveyance roller 8, the first feeding roller 16, the second feeding roller 9, and the like. The wide belt 7 is driven to rotate. A separation process (details will be described later) is performed by driving the separation belt 6 and the separation conveyance roller 8 described above, and the uppermost document P1 is conveyed in the document conveyance path (A). By driving the second feed roller 9, the document P1 is transported in the document transport paths (B) and (C) (see FIG. 13A). The document transport speed by the second feeding roller 9 and the document transport speed by the wide belt 7 are controlled to coincide with each other when the document P1 enters the transport path (d).
[0122]
Here, the document P <b> 1 that has passed through the separation unit S is detected by the separation sensor 30 and the skew sensor 31 before being conveyed by the first feeding roller 16.
[0123]
Further, based on the signals from the separation sensor 30 and the separation clock sensor 100b, it is determined whether or not the document transported by the separation transport roller 8 has reached the first feed roller 16, and when this determination is made. Then, the paper feed roller 5 is raised to a separation position away from the document.
[0124]
In the case of continuous paper feeding, the paper feeding roller 5 does not rise to the home position in FIG. 4 and is positioned at a position (a retreat position shown in FIG. 16) that is separated from the original P1, which is the uppermost paper, by about 3 to 5 mm. It is controlled to stop in the middle. As a result, the movement amount of the paper feed roller 5 is minimized, and as a result, the landing vibration of the paper feed roller 5 on the document P1 is reduced, the paper feed performance is improved, and the subsequent paper feed is started. Can be shortened.
[0125]
Further, when the paper feed roller 5 is raised as described above, the separation clutch 106 is turned off and the driving of the separation belt 6 and the separation conveyance roller 8 is stopped. Since the separation conveyance roller 8 is constituted by a one-way roller, it rotates following the movement of the original P1 being conveyed.
[0126]
By the way, simultaneously with the start-up of the separation motor 100 and the like described above (FIG. 15 ent2), a size check counter that starts counting with the clock signal input from the inverted clock is started (FIG. 15 ent3).
[0127]
On the other hand, when the registration sensor 39 detects the leading edge of the document, it is confirmed that the document P1 has been transported to the document transport path (c) (ent4 in FIG. 15).
[0128]
When the separation sensor 30 detects the passage of the trailing edge of the document (FIG. 15 ent5), a separation off counter that starts counting with a clock signal input from the separation clock is started (FIG. 15ent6). When the count for the distance L3 from the first feed roller 16 to the separation sensor 30 is completed (FIG. 15 ent7), the document is removed from the first feed roller 16 and the separation motor 100 is moved away. It turns off and the drive of the 1st feed roller 16 is stopped (FIG. 15 ent8). At this time, skew correction described later is performed.
[0129]
Further, when the paper feed sensor 35 detects the passage of the trailing edge of the document (FIG. 15 ent9), the size check counter is stopped (FIG. 15 ent10), and the size check process (details will be described later) based on the data is performed ( FIG. 15 ent11).
[0130]
Further, when the paper feed sensor 35 detects the passage of the trailing edge of the document (FIG. 15 ent9), the registration counter counted by the belt excitation clock is started (FIG. 15 ent12). Thereby, the standby position of the document (the position of the document stopped on the platen 3 before image reading) is determined according to the size of the document based on the value of the size check counter as the document size detecting means. .
[0131]
Thereafter, when this count ends by the distance L4 from the paper feed sensor 35 to the second feeding roller 9 (FIG. 15 ent13), the transport motor 101 is turned off (FIG. 15 ent14), and the driving of the second feeding roller 9 is stopped. Let Accordingly, the rotation of the second feeding roller 9 is stopped when the trailing end of the preceding document P1 passes through the nip of the second feeding roller 9.
[0132]
On the other hand, the paper feed roller 5 is retracted to the retracted position shown in FIG. 16, but the preceding document P1 is transported by the separation transport roller 8 and the trailing end of the preceding document P1 passes through the nip point of the paper feed roller 5. Then, it is lowered again to the contact position to prepare for the feeding operation of the succeeding document P2. Then, when the trailing edge of the preceding document P1 passes through the nip point of the first feeding roller 16, the separation clutch 106 is turned on, and feeding of the succeeding document P2 by the feeding roller 5 is started (FIG. 13A). reference). Whether the trailing edge of the preceding document P1 has passed the nip point of the paper feed roller 5 is determined based on signals from the separation sensor 30 and the separation clock sensor 100b.
[0133]
By the way, the rotation of the second feeding roller 9 is stopped when the trailing edge of the preceding document P1 passes through the nip of the second feeding roller 9 as described above, but the succeeding document P2 by the feeding roller 5 described above. Therefore, when the rotation of the second feed roller 9 is stopped, the subsequent document P2 has a leading end positioned near the upstream of the second feed roller 9 (the feed sensor 35 is disposed). It has been transported to the position that reaches the When the leading edge of the succeeding document P2 is detected by the paper feed sensor 35, the control for skew feeding is performed as in the case of the preceding document P1.
[0134]
On the other hand, the preceding document P1 has entered the document transport path (d) on the platen 3 and is transported alone by the wide belt 7, but the belt motor 102 has reached the point when the started registration counter is completed (see FIG. 15ent15) and stopped (FIG. 15ent16). As a result, the preceding document P1 is temporarily stopped when the trailing edge has advanced a predetermined distance after passing through the nip point between the paper feed sensor 35 and the second feeding roller 9 (see FIG. 13B).
[0135]
That is, if the distance between the trailing edge of the preceding document P1 and the nip point of the second feeding roller 16 is L8 and the length in the transport direction of the document P1 is Lph,
[0136]
[Formula 2]
L8 = L2-L5-Lph> 0
L2: Distance from the second image tip position R2 to the nip point of the second feeding roller 9
L5: Distance from the second image position R2 to the leading edge of the preceding document P1
It is set to become.
[0137]
At the same time as the driving of the belt motor 102 is stopped (FIG. 15 ent16), the path switching solenoid 107 is turned off (FIG. 15 ent17).
[0138]
When the document P1 is temporarily stopped in this way, the control circuit C outputs a conveyance completion signal to the apparatus main body 1 and waits for a conveyance start signal to be input from the apparatus main body 1.
[0139]
When the skew feeding control of the succeeding document P2 is completed and the control circuit C receives a conveyance start signal from the apparatus main body 1 (that is, the scanner 204 side), the control circuit C activates the wide belt 7. Then, the preceding document P1 is conveyed at the image forming speed.
[0140]
During this time, the driving of the second feed roller 9 remains stopped and the succeeding document P2 stands by, but the distance between the trailing edge of the preceding document P1 and the leading edge of the succeeding document P2 (hereinafter referred to as the inter-paper distance) is predetermined. When the distance (L8a) is reached, the second feeding roller 9 is activated, and the subsequent document P2 is conveyed at the same image forming speed as the preceding document P1. The start-up and transport speed of the second feed roller 9 is controlled so that the transport speed of the wide belt 7 and the transport speed of the second feed roller 9 coincide with each other when the distance between the sheets reaches L6. Is done. Here, since the timing at which the second feeding roller 9 is activated is later than the timing at which the wide belt 7 is activated, the distance L8a (the preceding document P1 at the moment when the second feeding roller 9 is activated). The distance between the trailing edge and the leading edge of the succeeding document P2 is larger than the distance L6. The start timing of the second feeding roller 9 is determined by taking into consideration the loss of the document P2 when the second feeding roller 9 is accelerated, and the distance between the preceding document P1 (final sheet distance). The timing is set to be L6.
[0141]
When the preceding document P1 reaches the second image destination position R2, the control circuit C outputs an image destination arrival signal to the apparatus body 1, and the apparatus body 1 receives the image and reads the image of the preceding document P1 (the first image). 1-flow reading mode) is started. In this half-size single-sided document conveyance mode, the scanner 204 is conveyed by the wide belt 7 while being disengaged from the second feeding roller 9 while being stopped at the second image tip position R2. Scan the original image.
[0142]
By the way, when the rear end of the document P1 is removed from the second feeding roller 9 during such image reading, the impact generated at that time may adversely affect the image reading accuracy. In the case of the embodiment, as described in the section <Positional relationship between the document and the scanner at the time of image reading>, the trailing edge of the document P1 is positioned at the second feeding roller 9 when the image reading is started. There is no such problem because it is out of the way.
[0143]
When the image reading ends, the document P1 is stopped at a position where the document trailing edge and the second image tip position R2 are at a predetermined distance L9 (see FIG. 13C). At this time, the succeeding document P2 is stopped at a position where the leading edge of the document and the second image destination position R2 are at a predetermined distance L5, and the subsequent document P3 is further stopped by the stopped second feeding roller 9. Waiting in a state where a loop for skew feeding is formed.
[0144]
When a conveyance start signal is input from the apparatus main body 1 in this state, the control circuit C activates the wide belt 7 (belt motor 102) to start conveyance of the subsequent original P2, and the original P2 is moved to the second destination position R2. When the value reaches, the apparatus body 1 reads the image of the original P2.
[0145]
Here, FIG. 14A is a diagram showing a state when the document P2 reaches the second image tip position R2 and image reading is started, and FIG. 14B shows the image reading of the document P2. FIG. 10C is a diagram illustrating a state when image reading of the document P2 is completed.
[0146]
By the way, if the trailing edge of the document P2 falls out of the second feeding roller 9 during such image reading, the impact generated at that time may adversely affect the image reading accuracy. In the case of the present embodiment, as described in the section <Positional relationship between the document and the scanner at the time of image reading>, the trailing edge of the document P2 is the second feeding roller when the image reading is started. 9 (see FIG. 14A), there is no such problem.
[0147]
Further, even if the subsequent document P3 is removed from the second feeding roller 9 during such image reading, the impact generated at that time may adversely affect the image reading accuracy. In this embodiment, L2 (distance between the nip portion of the second feeding roller 9 and the second image tip position R2), L6 (distance between sheets), and Lph (length in the document transport direction) are expressed by the following formulas. The following document P3 and the second feeding roller 9 are disengaged when the scanner 204 is not reading an image (that is, the image reading of the preceding document P2 is completed). And before the image reading of the subsequent original P3 is started), there is no such problem.
[0148]
[Formula 3]
L2 <L6 + Lph
Here, since L2-L5-Lph> 0 as described above,
L5 + Lph <L2 <L6 + Lph
During this time, a discharge process (details will be described later) of the preceding document P1 is performed, and the document is discharged onto the discharge tray 10.
[0149]
Details of each process described above will be described below.
<Pickup DOWN treatment>
Here, the pickup DOWN process will be described with reference to FIG.
[0150]
If the paper feed roller 5 is at the home position (see FIG. 4), the paper feed roller home sensor 45 is turned on. In this state, when the swing motor 103 is driven to lower the lift arm 51 and the swing arm 53 (pickupdwn 1), the paper feed roller home sensor 45 is turned off (pickupdwn 2). Further, when the elevating arm 51 and the swing arm 53 are lowered, the swing position sensor 46 is shielded by the swing arm flag 54 and outputs an ON signal while the paper feed roller 5 is in contact with the uppermost document P1. Then, based on this ON signal, the drive of the swing motor 103 is stopped (pickupdwn4). In this state, the paper feed roller 5 abuts against the original P1 by its own weight and always applies a stable feeding force to the original P1 (see FIG. 18).
[0151]
As described above, when the lift arm 51 is lowered even after the paper feed roller home sensor 45 is turned off (pickupwn2), the engagement between the positioning pin 51c and the swing arm 53 is released, and the swing arm 53 is released. The relative positional relationship between the lift arm 51 and the lift arm 51 starts to shift, but the lift arm 51 is stopped based on the ON signal from the swing position sensor 46, and the shift amount is constant (see FIG. 18). <Separation processing and skew correction>
Here, separation processing and skew feeding correction will be described with reference to FIG.
[0152]
When the separation motor 100 is driven as described above (FIG. 19 sepa1), the separation belt 6 and the separation conveyance roller 8 are each driven to rotate in the direction of the arrow, and the documents P conveyed from the document tray 4 are separated one by one. Then, it is further conveyed to the downstream document conveyance path (b). When the leading edge of the document P1 reaches a predetermined position on the downstream side of the separation conveyance roller 8, the separation sensor 30 is turned on (FIG. 19 sepa2), and the second processing is performed so that the separation process is completed within a predetermined time range. The speed of the separation motor 100 is controlled based on the remaining transport distance until the leading edge of the document abuts against the feed roller 9 and a loop is formed and the elapsed time until the separation sensor 30 is turned on (FIG. 19 sepa 3).
[0153]
When the leading edge of the document P1 is detected by the paper feed sensor 35 disposed near the upstream side of the second feeding roller 9 (FIG. 19 sepa4), a separation loop counter that counts by a clock signal input from the separation clock is generated. Starting (FIG. 19 sepa5), the driving of the separation motor 100 (driving of the first feeding roller 16) is stopped after the set count is finished (FIG. 19 sepa6, sepa7). As a result, the front end of the original P1 is abutted against the nip portion of the stopped second feeding roller 9, and is stopped in a state where a predetermined amount of loop is formed, and the known skew feeding is performed.
[0154]
By the way, when double feeding of originals occurs, the lower original is returned to the original tray 4 side by the separation belt 6, but before the original reaches the paper supply roller 5, the paper supply roller 5 is moved. You may make it move to a separation position.
<Size check process>
Here, the size check process will be described with reference to FIG.
[0155]
In this size check process, the original document size (feed direction) is corrected by adding the distance from the nip position of the second feed roller 9 to the paper feed sensor 35 to the size check counter data as means for determining the document size. Length). At this time, the document is conveyed by the second feeding roller 35 and the wide belt 7, and the feeding amount and the count value by the belt excitation clock surely match. Thereafter, size determination of A5, B5, A4, B5R, A4R, B4, A3, etc. is performed based on the corrected size data.
<Document scanning process>
Here, the document reading process will be described with reference to FIG.
[0156]
When the belt motor 102 is started (FIG. 21 move 1) and the wide belt 7 is driven, the document P 1 is conveyed along the platen 3 as described above. Simultaneously with the activation of the belt motor 102, an image destination on-counter counted by the belt excitation clock is started (FIG. 21 move2). The belt motor speed at this time is controlled at a constant speed by outputting an excitation clock signal based on the flow reading speed data (V) received from the apparatus main body 1.
[0157]
Then, after the wide belt 7 is activated, the second feeding roller 9 is activated when the original on which image reading is performed is advanced a predetermined distance (Lx), and the subsequent original is conveyed to the reading position (FIG. 21 move3). This distance Lx is variably controlled based on the document size obtained by the size check process described above.
[0158]
Thereafter, when the counting of the image destination on-counter ends (FIG. 21 move 4), the image destination signal is transmitted to the apparatus main body 1 (FIG. 21 move 5).
[0159]
After receiving the image tip signal, the apparatus body 1 performs actual image reading by calculating and controlling the time until the leading edge of the document reaches the optical system fixing position (R2) during the flow reading. Specifically, the scanner 204 is activated, and the scanner 204 reads a document image.
[0160]
The image destination signal is turned off after a predetermined time has elapsed (FIG. 21 move 6, 7, 8), and the reading of the document image is completed. Further, when the trailing edge of the document passes the reading position (R2), the belt motor 102 is turned off (FIG. 21 move9).
[0161]
The flow reading speed data (V) may be equal to or different from the reading speed (V1) when the optical system is moved. In particular, when V> V1, the original image reading is completed in a shorter time than the normal optical system moving reading, so that the copying speed is improved.
<Pickup UP processing>
Here, the pickup UP processing will be described with reference to FIG.
[0162]
When the swing motor 103 is rotationally driven in the direction opposite to that during the pickup DOWN process (pickup 1 in FIG. 22), the paper feed roller 5 is raised via the lift arm 51 and the swing arm 53. When the paper feed roller home sensor 45 is turned on, the drive of the swing motor 103 is stopped (pickup 2 and pickup 3 in FIG. 22), and the paper feed roller 5 is held at the upper limit position.
<Discharge processing>
Here, the paper discharge process will be described with reference to FIG.
[0163]
When the belt motor 102 is started as described above, the wide belt 7 and the manual registration roller 11 are rotationally driven. Here, the manual registration roller 11 is driven at a conveyance speed equal to the conveyance speed of the wide belt 7, and the original P1 and the original P2 are conveyed while the distance between the sheets is L6. Further, when the belt motor 102 is started, the paper discharge motor 104 is started (FIG. 23ejct1), and the paper discharge roller 12 and the manual paper feed roller 13 are driven to rotate. Here, the paper discharge roller 12 is driven at a conveyance speed equal to or slightly higher than the conveyance speed of the wide belt 7.
[0164]
On the other hand, the discharge flapper solenoid 109 is in an off state, and the discharge flapper 26 is positioned at a lower end than the platen 3 as shown by a chain line in FIG. Accordingly, the preceding document P1 on the platen 3 is conveyed by the wide belt 7, the manual registration roller 11 and the sheet discharge roller 12 through the document conveyance path (d) to the document discharge path (n), and the sheet discharge tray 10 Discharged to the top.
[0165]
The manual registration sensor 34 detects the leading edge of the original P1 to be discharged, thereby confirming that the original P1 is transported through the original discharge path (n) (FIG. 23ejct2), and the sensor 34 is located after the original P1. When it is detected that the trailing edge of the preceding document P1 has passed through the nip of the manual registration roller 11 (FIG. 23ejct3), the driving of the belt motor 102 is stopped (FIG. 23ejct4). As a result, the driving of the wide belt 7 and the manual registration roller 11 is stopped, and the original P1 is independently conveyed by the paper discharge roller 12 and the like. At this time, the succeeding document P2 has been read and is conveyed by the wide belt 7, and the subsequent document P3 is conveyed by the second feeding roller 9 and the wide belt 7. (See FIG. 14 (c)). Then, the document P2 is stopped on the platen 3 together with the subsequent document P3.
[0166]
Simultaneously with the stop of driving of the belt motor 102, a paper discharge counter that starts counting by a clock signal input from the paper discharge clock is started (FIG. 23ejct5), and after this setting count is finished (FIG. 23ejct6), the paper discharge motor 104 is driven. It stops (FIG. 23 ejct 7). As a result, the driving of the paper discharge roller 12 and the manual paper feed roller 13 is stopped, but at this time, the original P1 has already passed through the original discharge path (nu) and passed through the paper discharge roller 12, and the paper discharge tray. 10 is discharged. [2-2] Large size single-sided document transport mode
First, an outline of the operation when a large-size single-sided document is conveyed will be described with reference to FIG.
[0167]
FIG. 24 is a flowchart showing the outline of the operation.
[0168]
When transporting a large-size single-sided document, first, the above-described pickup DOWN process is performed, and the paper feed roller 5 is lowered and brought into contact with the document P1 (FIG. 24 draft 2 md 1).
[0169]
Thereafter, the separation process described above is executed, and only the uppermost document P1 is separated (FIG. 24 draft 2 md 2), and then the paper feed process is executed (FIG. 24 draft 2 md 3). The operation up to this point is the same as in the half-size single-sided document conveyance mode described above.
[0170]
Then, when the document P1 is conveyed to a predetermined position on the platen 3, the document flow scanning process (second flow scanning mode) is executed, and the scanner 204 of the apparatus body 1 is stopped at the third image destination position R3. In this state, the original image is read (FIG. 24 draft 2 md 4). Note that since the third image destination position R3 is in the vicinity of the paper discharge tray 10, as a result, the above-described document flow reading process and the paper discharge process are continuously performed (FIG. 24 draft 2 md5), and the image is read. The original P1 is discharged onto the paper discharge tray 10.
[0171]
After that, it waits for the separation sensor 30 to detect the trailing edge of the document (FIG. 24 draft 2 md 6). When the detection is made, the document set detection sensor 40 determines whether or not the document being conveyed is the final document (FIG. 24). 24 draft 2 md 7).
[0172]
If it is not the final document, the above operation is repeated (FIG. 24 draft 2 md 2 to draft 2 md 7). If it is the final document, the pickup UP process is performed to return the paper feed roller 5 to the upper limit position and the series of processes is completed (FIG. 24 draft 2 md 8). .
[0173]
Next, details of the operation when a large-size single-sided original is conveyed will be described with reference to FIGS. 25 and 26. FIG.
[0174]
FIG. 25 and FIG. 26 are schematic diagrams showing the flow of a document when a large-size single-sided document is conveyed.
[0175]
The operations from the pickup DOWN process to the paper feed process (FIG. 24 draft 2 md 1 to draft 2 md 3) are the same as those in the half-size single-sided document conveyance mode described above.
[0176]
That is, also in this mode, the path switching solenoid 107 is turned on similarly to the above-described half-size single-sided document conveyance mode, the reverse feeding path (f) is closed, and the document conveyance path (c) is opened. Is done. The wide belt 7 is driven when the preceding document P1 is conveyed, and has a conveying speed equal to that of the second feeding roller 9 before the preceding document P1 enters the platen 3. Accordingly, the preceding original P1 is conveyed to the platen 3 through the original conveying path (c) by the above-described two rollers 16 and 9 and the wide belt 7 (see FIG. 25A).
[0177]
The rotation of the second feeding roller 9 is stopped when the trailing edge of the preceding document P1 passes through the nip of the second feeding roller 9 (see FIG. 25B).
[0178]
On the other hand, the feed roller 5 is retracted to the retracted position after feeding the preceding document P1, but when the trailing edge of the preceding document P1 passes the nip point of the feed roller 5, it is lowered again to feed the succeeding document P2. Prepare for paper movement. When the trailing edge of the preceding document P1 passes through the nip point of the first feeding roller 16, the separation clutch 106 is turned on, and the feeding of the succeeding document P2 by the sheet feeding roller 5 is started.
[0179]
By the way, the rotation of the second feeding roller 9 is stopped when the trailing edge of the preceding document P1 passes through the nip of the second feeding roller 9 as described above, but the succeeding document P2 by the feeding roller 5 described above. Therefore, when the rotation of the second feed roller 9 is stopped, the subsequent document P2 has a leading end positioned near the upstream of the second feed roller 9 (the feed sensor 35 is disposed). It has been transported to the position that reaches the When the leading edge of the succeeding document P2 is detected by the paper feed sensor 35, the control for skew feeding is performed as in the case of the preceding document P1.
[0180]
On the other hand, the preceding document P1 has entered the document transport path (d) on the platen 3 and is transported alone by the wide belt 7, and its rear end passes through the nip point between the paper feed sensor 35 and the second feed roller 9. Then, the vehicle stops once after a predetermined distance has elapsed (see FIG. 25B). As a result, the preceding document P1 is temporarily stopped when the trailing edge has advanced a predetermined distance after passing through the nip point between the paper feed sensor 35 and the second feeding roller 9 (see FIG. 25B).
[0181]
That is, if the distance between the trailing edge of the preceding document P1 and the nip point of the second feeding roller 16 is L10, and the length in the transport direction of the document P1 is Lph,
[0182]
[Formula 4]
L10 = L3-L5-Lph> 0
L3: distance from the third image tip position R3 to the nip point of the second feed roller 9
L5: Distance from the third image destination position R3 to the leading edge of the preceding document P1
It is set to become.
[0183]
When the document P1 is temporarily stopped in this way, the control circuit C outputs a conveyance completion signal to the apparatus main body 1 and waits for a conveyance start signal to be input from the apparatus main body 1.
[0184]
When the skew feeding control of the succeeding document P2 is completed and the control circuit C receives a conveyance start signal from the apparatus main body 1, the control circuit C activates the wide belt 7 to image the preceding document P1. Transport at the forming speed.
[0185]
During this time, the driving of the second feed roller 9 remains stopped and the succeeding document P2 stands by, but the distance between the trailing edge of the preceding document P1 and the leading edge of the succeeding document P2 (hereinafter referred to as the inter-paper distance) is predetermined. When the distance is reached, the second feeding roller 9 is activated, and the subsequent document P2 is conveyed at the same image forming speed as the preceding document P1. The starting and conveying speeds of the second feeding roller 9 are controlled so that the conveying speed of the wide belt 7 and the conveying speed of the second feeding roller 9 coincide with each other when the above-mentioned inter-paper distance becomes L11. Is done.
[0186]
When the preceding document P1 reaches the third image destination position R3, the control circuit C outputs an image destination arrival signal to the apparatus body 1, and the apparatus body 1 receives this and starts reading the image of the preceding document P1. (See FIG. 26 (a)).
[0187]
By the way, when the rear end of the document P1 is removed from the second feeding roller 9 during such image reading, the impact generated at that time may adversely affect the image reading accuracy. In the case of the embodiment, as described in the section <Positional relationship between the document and the scanner at the time of image reading>, the trailing edge of the document P1 is positioned at the second feeding roller 9 when the image reading is started. There is no such problem because it is out of the way.
[0188]
Further, even if the subsequent document P2 is removed from the second feeding roller 9 during such image reading, the impact generated at that time may adversely affect the image reading accuracy. In the present embodiment, L3 (distance between the nip portion of the second feeding roller 9 and the third image destination position R3), L11 (distance between sheets), and Lph (length in the document transport direction) are expressed by the following equations. Since the relationship is set so that the subsequent original P2 comes off the second feeding roller 9 after the image reading of the preceding original P1 is completed, there is no such problem.
[0189]
[Formula 5]
L3 <L11 + Lph
Here, since L3-L5-Lph> 0 as described above,
L5 + Lph <L3 <L11 + Lph
When the image reading of the preceding original P1 is completed, the wide belt 7 is stopped after being driven for a predetermined time, and the subsequent original P2 is conveyed to the position shown in FIG. 26B and stopped at the position. . Since the inter-paper distance L11 is set to be larger than the distance from the leading edge of the succeeding document P2 to the nip point of the manual registration roller 11, the trailing edge of the preceding document P1 is manually fed when the succeeding document P2 stops. Passing through the nip point of the registration roller 11, the document P <b> 1 is independently conveyed and discharged by the paper discharge roller 12.
[3] Double-sided document transport mode
Next, the operation in the duplex original conveyance mode will be described separately for the half size duplex original conveyance mode and the large size duplex original conveyance mode.
[3-1] Half-size double-sided document conveyance mode
First, an outline of an operation when a half-size double-sided original is conveyed will be described with reference to FIG.
[0190]
When a half-size double-sided original is conveyed, the above-described pickup DOWN process is executed, and the paper feed roller 5 is lowered and brought into contact with the original P1 (doublelem 1). Thereafter, the separation process described above is executed, and only one uppermost document P1 is separated and fed (doublebled2). The operation up to this point is the same as in the above-described single-sided document conveyance mode.
[0191]
Next, a pre-inversion process is performed to invert the front and back of the document P1 (doublebled3), and the inverted document P1 is placed on the platen 3 with the second side facing down. Then, the optical system moving document reading is executed (doubled4), and the document image on the second surface is read while moving the scanner 204 of the apparatus main body 1.
[0192]
When this document reading is completed, a reversal process is performed using the reversal feed / discharge path (e), the reversal feed path (g) and the document transport path (c) (doublelem 5). Image reading is performed (doublelem 6).
[0193]
During such reading processing, the document set detection sensor 40 determines whether the document is the final document (doublelem 7). If the document is not the final document, a paper discharge process for discharging the document P1 onto the paper discharge tray 10 is performed (doublelem 8), and the above operation is repeated (doubled2 to doubled7). If the document is a final document, the paper discharge process is performed (doubled 9), the pickup UP process is performed to return the paper feed roller 5 to the upper limit position (doubled 10), and the series of processes is completed.
[0194]
Next, details of the operation when a half-size double-sided original is conveyed will be described with reference to FIGS.
[0195]
FIGS. 28 to 31 are schematic views showing the flow of a document when a half-size double-sided original is conveyed, and FIG. 32 is a flowchart showing details of the operation when conveying a half-size double-sided original. .
[0196]
Now, when the operator inputs a copy condition on the operation unit and presses a start key (copy key), the separation motor 100 and the transport motor 101 are activated (FIG. 32 pretrn1). As a result, the first feeding roller 16, the second feeding roller 9, the first reversing roller 17 and the second reversing roller 18 are rotationally driven, and the above-described separation processing and skew correction are performed.
[0197]
Simultaneously with the activation of the separation motor 100 and the like, a size check counter that starts counting with a clock signal input from the inverted clock is started (FIG. 32 pretrn2).
[0198]
On the other hand, in this mode, the reverse sheet feeding flapper 22 is held at the position indicated by the solid line in FIG. 3 while the path switching solenoid 107 is off, and closes the document conveying path (C) and opens the reverse feeding path (H). It is open. Further, the reverse flapper solenoid 108 is in an off state, and the reverse flapper 23 is held at the position of the solid line in FIG. 3 to close the reverse feed path (g) and open the reverse feed path (re). Accordingly, when the second feeding roller 9 is driven to rotate, the document P1 whose tip is abutted against the second feeding roller 9 is guided to the reverse feeding path (h) (f) (re) side. Then, pre-inversion processing is performed (see FIG. 28A). Note that whether or not the document P1 has been conveyed to the reverse feeding path (h) is confirmed by the registration sensor 39 detecting the leading edge of the document (pretrn 3 in FIG. 32).
[0199]
On the other hand, when the separation sensor 30 detects the passage of the trailing edge of the document (FIG. 32 pretrn 4), the separation off counter that starts counting by the clock signal input from the separation clock is started (FIG. 32 pretrn 5). When the counting for the distance L3 from the first feeding roller 16 to the separation sensor 30 is completed (FIG. 32 pretrn6), the document has been separated from the first feeding roller 16 and the separation motor 100 is removed. It is turned off to stop the driving of the first feeding roller 16 (FIG. 32 pretrn7).
[0200]
When the paper feed sensor 35 detects the passage of the trailing edge of the document (FIG. 32 pretrn 8), the size check counter is stopped (FIG. 32 pretrn 9), and the size check process is performed based on the data (FIG. 32 pretrn 10).
[0201]
Further, when the registration sensor 39 detects the passage of the trailing edge of the document (FIG. 32 pretrn 11), a pre-inversion counter counted by the inversion excitation clock is started (FIG. 32 pretrn 12). When the pre-inversion counter is completed (FIG. 32 pretrn 13), the transport motor 101 is turned off (FIG. 32 pretrn 14). As a result, the document P1 is stopped at a predetermined position where the trailing edge has passed through the reverse feeding path (h).
[0202]
Then, after a lapse of a predetermined time after the conveyance motor 101 is turned off, the conveyance motor 101 is activated in the reverse direction, and the first reverse roller 17 and the second reverse roller 18 are rotationally driven in the reverse direction, and the belt motor 102 is When activated, the wide belt 7 is rotationally driven in the forward direction (FIG. 32 pretrn 15). As a result, the document P1 is guided to the document transport path (d) on the platen 3 through the reverse feed / discharge path (e) (see FIG. 28B).
[0203]
When the document P1 is transported from the document transport path (b) to the reverse feed path (h) (f) (re) side, when the rear end of the document P1 passes through the one-way flapper 24, the feeding is performed. The exhaust flapper 25 has been moved to the solid line position in FIG. Accordingly, when the pre-reversed document P1 is transported to the document transport path (d) through the reversing supply / discharge path (e), the leading edge of the document P1 is prevented from colliding with the end of the platen 3. . Further, the conveyance speed of the first reverse roller 17 and the like and the conveyance speed of the wide belt 7 are controlled so as to be constant except in special cases.
[0204]
On the other hand, it is confirmed that the original P1 is conveyed to the reverse feeding / discharging path (e) based on the detection of the passage of the front end of the original by the reverse sensor 38 (FIG. 32 pretrn 16), and the reverse sensor 38 detects the passage of the rear end of the original. When detected (FIG. 32 pretrn 17), the driving of the carry motor 101 is stopped (FIG. 32 pretrn 18).
[0205]
Further, based on the detection signal of the reversing sensor 38 (the signal for detecting the trailing edge of the document), a pre-feed counter that is counted by the belt excitation clock is started (FIG. 32 pretrn 19). When the pre-feed counter finishes counting (FIG. 32 pretrn 20), the driving of the belt motor 102 is stopped (FIG. 32 pretrn 21). As a result, the driving of the wide belt 7 is stopped, and the document P1 is stopped in a state where the second surface is at a predetermined position on the platen 3 (see FIG. 29A).
[0206]
In this state, the scanner 204 of the apparatus main body 1 is scanned, and the image on the second surface of the document P1 is read.
[0207]
When the image reading on the second surface of the document P1 is completed, the document is reversed. Here, the inversion process will be described with reference to FIG.
[0208]
The reverse flapper 23 is held at the position of the solid line in FIG. 3 as described above to close the reverse feed path (g) and open the reverse feed path (re). The reverse flapper solenoid 108 is turned on (FIG. 33 trn1), and the reverse flapper 23 is switched to the chain line position in FIG. 3 to open the reverse feed path (g) and close the reverse feed path (re).
[0209]
Further, the path switching solenoid 107 is turned on (FIG. 33 trn1), the reverse feed flapper 22 is held at the chain line position in FIG. 3 to open the document transport path (C) and close the reverse feed path (H). The supply / discharge flapper 25 is held at the chain line position in FIG.
[0210]
Next, the belt motor 102 is activated to rotate and drive the wide belt 7 in the clockwise direction (FIG. 33 trn2), and the document P1 is conveyed from the reading position on the platen to the reverse feeding / discharging path (e). Further, the conveyance motor 101 is activated to rotate the second feeding roller 9, the first reversing roller 17 and the second reversing roller 18 in the clockwise direction (FIG. 33 trn2), and the reversing feeding path (f) (t) ) And the document P1 is transported along the document transport path (c) (see FIG. 29B).
[0211]
By the way, when the document P1 on the platen 3 is discharged to the reverse feeding / discharging path (e), the leading edge of the document is detected by the reverse sensor 38 (FIG. 33 trn3). The counting counter is started (FIG. 33 trn4). When the count of the counter is finished, the belt motor 102 is turned off (FIG. 33 trn5, trn6), and is driven to rotate counterclockwise after a predetermined time (FIG. 33trn7). Accordingly, the document P1 being transported to the document transport path (c) is guided to the document transport path (d) by the wide belt 7. The wide belt 7 is stopped and driven in the opposite direction while the first reverse roller 17 and the second reverse roller 18 are transporting the document P1. Accordingly, the document P1 is transported to the reading position of the document transport path (d) without stopping. The conveyance speed of the wide belt 7 is controlled so as to coincide with the conveyance speed of the second feeding roller 9 by the time when the leading edge of the document P1 enters the document conveyance path (d).
[0212]
Further, the paper feed sensor 35 detects the passage of the leading edge of the document, confirms that the document P1 is conveyed through the reverse feeding path (g) (FIG. 33 trn8), and the registration sensor 39 passes the trailing edge of the document. Is detected (FIG. 33trn9), the transport motor 101 is turned off (FIG. 33trn10). Accordingly, the rotation of the second feeding roller 9 is stopped when the trailing end of the preceding document P1 passes through the nip of the second feeding roller 9. Accordingly, the preceding document P1 that has entered the document transport path (d) is transported independently by the wide belt 7.
[0213]
Further, at the same time that the paper feed sensor 35 detects the passage of the trailing edge of the document, a reverse paper feed counter that is counted by the belt excitation clock is started (FIG. 33 trn11). When the count of the reverse paper feed counter is completed (FIG. 33 trn12), the belt motor 102 is turned off (FIG. 33trn13). As a result, the driving of the wide belt 7 is stopped, and the document P1 is stopped at a predetermined position on the platen 3.
[0214]
At this position, the scanner 204 of the apparatus main body 1 is scanned, and image reading of the first surface of the document P1 is performed.
[0215]
Thereafter, the reverse flapper solenoid 108 is turned off to switch the reverse flapper 23 to the solid line position in FIG. 3, and the path switching solenoid 107 is turned off to switch the reverse feed flapper 22 and the supply / discharge flapper 25 to the solid line position in FIG. FIG. 33 trn14).
[0216]
In the reversing process, since the wide belt 7 is driven to rotate in the forward direction (FIG. 33 trn7), the first reversing roller 17 and the wide belt 7 pull the document P1. Since the nip force is stronger, the document P1 is conveyed by the reverse roller 17. However, in the case of a large-size document (document that is long in the feed direction), the conveying force of the wide belt 7 becomes larger, and smooth document conveyance may be hindered. Therefore, in this case, the wide belt 7 is driven in the opposite direction at a timing based on the detection result of the document trailing edge detection sensor 41 or the like.
[0217]
On the other hand, before and after the detection of the trailing edge of the preceding document P1 by the sheet feeding sensor 35, the feeding roller 5 and the separation unit S are driven to separate and feed the succeeding document P2 from the document tray 4, and the second feeding roller. At 9, skew feeding is performed. Then, the second feeding roller 9, the first reversing roller 17 and the second reversing roller 18 are driven to perform the pre-reversing process of the succeeding document P2 (see FIG. 30A). The succeeding document P2 completes the pre-reversing process while the image of the preceding document P1 is being read, and stands by with its leading end nipped by the first reversing roller 17.
[0218]
When the image reading of the preceding document P1 is completed, the reverse rotation of the first reversing roller 17 and the second reversing roller 18 and the normal rotation of the wide belt 7 are started, and the preceding document P1 and the succeeding document P2 are placed on the platen 3 in a predetermined manner. Is placed in a state separated by a distance L12 between the sheets (see FIG. 30B).
[0219]
In this state, the scanner 204 of the apparatus main body 1 is scanned, and the image on the second surface of the subsequent document P2 is read.
[0220]
When this image reading is completed, the reversing process of the succeeding document P2 starts as in the case of the preceding document P1, and the succeeding document P2 is discharged to the reversing supply / discharge path (e). The preceding original P1 is conveyed in the direction of the reverse feeding / discharging path (e) along with the reversing process. However, since the inter-paper distance L12 is set to an appropriate value, the reverse feeding / discharging path (e) It remains in the state of being placed on the platen 3 without being discharged.
[0221]
Thereafter, the wide belt 7 is reversely driven, and the subsequent original P2 passes through the reverse feeding / discharging path (e), the reverse feeding path (f), the reverse feeding path (g), and the original conveying path (c). Guided to the document transport path (d).
[0222]
The wide belt 7 is stopped in the state of FIG. 31A, and image reading of the first surface of the succeeding document P2 is performed in this state. At this time, the distance between the original P1 and the original P2 is L13. Further, the subsequent document P3 is fed from the document tray 4 and waits in a state where it is nipped by the first reverse roller 17.
[0223]
When the image reading of the first surface of the subsequent document P2 is completed, the reverse rotation of the first reverse roller 17 and the second reverse roller 18, the normal rotation of the wide belt 7, and the rotation of the paper discharge roller 12 are started. P3 and P2 and the preceding document P1 are simultaneously conveyed to the discharge tray 10 side.
[0224]
When the succeeding document P3 is placed on the platen 3, the wide belt 7 is stopped, and the image of the succeeding document P3 is read (see FIG. 31B). At this time, the preceding document P1 has already passed through the nip of the manual registration roller 11 at the rear end thereof, and is therefore conveyed alone by the discharge roller 12 and discharged to the discharge tray 10.
[0225]
The above operation is repeated when scanning a plurality of originals. However, when the final image reading (that is, the image reading of the first surface of the final original Pn) is completed, the platen 3 is placed on the platen 3. Two originals (the final original Pn and the final previous original Pn-1) are placed. Then, these originals Pn and Pn-1 are continuously discharged to the discharge tray 10 by driving the wide belt 7.
[3-2] Large-size duplex document transport mode
Next, the operation when a large-size double-sided original is conveyed will be described with reference to FIGS.
[0226]
34 to 37 are schematic views showing the flow of a document when a large-size double-sided document is conveyed.
[0227]
Also in this mode, as in the case of the half size, the reverse feeding flapper 22 is held at the position of the solid line in FIG. 3 to close the document conveying path (C) and open the reverse feeding path (H), and reverse The flapper 23 is held at the position of the solid line in FIG. 3 to close the reverse feed path (g) and open the reverse feed path (re).
[0228]
Now, when the operator inputs a copy condition on the operation unit and presses the start key (copy key), the separation motor 100 and the conveyance motor 101 are activated to perform separation processing and skew correction as in the case of the half size. Done.
[0229]
Further, the original P1 is guided to the reverse feeding path (h) (f) (re) side and pre-reverse processing is performed (see FIG. 34 (a)), and based on the fact that the conveyance motor 101 is stopped. The end is stopped at a predetermined position after passing through the reverse feeding path (H).
[0230]
Next, after the conveyance motor 101 is stopped and a predetermined time has elapsed, the motor 101 is started in the reverse direction, and the first reverse roller 17 and the second reverse roller 18 are rotationally driven in the reverse direction. 102 is activated and the wide belt 7 is rotationally driven in the forward direction. As a result, the document P1 is guided to the document transport path (d) on the platen 3 through the reverse feed / discharge path (e) (see FIG. 34B). At this time, since the supply / discharge flapper 25 is moved to the solid line position in FIG. 3, the leading edge of the document P <b> 1 is prevented from colliding with the edge of the platen 3. Further, the conveyance speed of the first reverse roller 17 and the like and the conveyance speed of the wide belt 7 are controlled so as to be constant except in special cases.
[0231]
When the trailing edge of the document P1 is detected by the reversing sensor 38, the driving of the wide belt 7 is stopped after a predetermined time has elapsed, and the document P1 is placed at the image tip position in the fixed reading mode (FIG. 35A). reference).
[0232]
In this state, the scanner 204 of the apparatus main body 1 is scanned, and the image on the second surface of the document P1 is read.
[0233]
When the image reading on the second surface of the document P1 is completed, the document is reversed.
[0234]
That is, the reverse flapper 23 is switched to the chain line position in FIG. 3 to open the reverse feed path (g) and close the reverse feed path (re), and the reverse feed flapper 22 is set to the chain line position in FIG. The document feed path (C) is held and the reverse feeding path (H) is closed, and the supply / discharge flapper 25 is held at the chain line position in FIG.
[0235]
On the other hand, when the above-described image reading is completed, the belt motor 102 and the conveyance motor 101 are activated, and the wide belt 7, the second feeding roller 9, the first reverse roller 17, and the second reverse roller 18 are rotationally driven in the reverse direction. The As a result, the document P1 is conveyed along the reverse feeding / discharging path (e) → the reverse feeding path (f) to (g) → the document conveyance path (c) (see FIG. 35B). Thereafter, the document P1 is guided to the document transport path (d) via the document transport path (c).
[0236]
By the way, when the original P1 on the platen 3 is discharged to the reverse feeding / discharging path (e), the leading edge of the original is detected by the reverse sensor 38. After a predetermined time has elapsed from the detection timing, the wide belt 7 is detected. Is stopped and then rotated in the positive direction. Accordingly, the document P1 being transported to the document transport path (c) is guided to the document transport path (d) by the wide belt 7. The conveyance speed of the wide belt 7 is controlled so as to coincide with the conveyance speed of the second feeding roller 9 by the time when the leading edge of the document P1 enters the document conveyance path (d).
[0237]
The rotation of the second feeding roller 9 is stopped when the trailing edge of the preceding document P1 passes through the nip of the second feeding roller 9.
[0238]
The preceding document P1 that has entered the document transport path (d) is independently transported by the wide belt 7, but after the trailing edge is detected by the paper feed sensor 35 and transported a predetermined distance, the wide belt 7 is driven. Is stopped. As a result, the preceding document P1 is stopped in a state where the first surface is at a predetermined position on the platen 3 (image destination position in the fixed reading mode).
[0239]
At this position, the scanner 204 of the apparatus main body 1 is scanned, and image reading of the first surface of the document P1 is performed.
[0240]
On the other hand, before and after the detection of the trailing edge of the preceding document P1 by the sheet feeding sensor 35, the feeding roller 5 and the separation unit S are driven to separate and feed the succeeding document P2 from the document tray 4, and the second feeding roller. At 9, skew feeding is performed. Then, the second feeding roller 9, the first reversing roller 17 and the second reversing roller 18 are driven to perform the pre-reversing process of the succeeding document P2 (see FIG. 36A). The succeeding document P2 completes the pre-reversing process while the image of the preceding document P1 is being read, and stands by with its leading end nipped by the first reversing roller 17 (FIG. 36 ( b)). At this time, the space between the preceding document P1 and the waiting subsequent document P2 is controlled to be L14.
[0241]
When the image reading of the preceding original P1 is completed, the reverse rotation of the first reverse roller 17 and the second reverse roller 18 and the normal rotation of the wide belt 7 are started, and the subsequent original P2 is conveyed to the platen 3 and stopped at that position. (See FIG. 37). At this time, the trailing edge of the preceding document P1 passes through the nip of the manual registration roller 11.
[0242]
In this state, the scanner 204 of the apparatus main body 1 is scanned, and the image on the second surface of the subsequent document P2 is read.
[0243]
Thereafter, the same operation as this is continued until the final document Pn.
[4] Manual feed mode
Next, the operation in the manual feed mode will be described with reference to FIGS.
[0244]
First, the outline of the action will be described with reference to FIGS. FIG. 38 is a flowchart showing an outline of the operation in the manual feed mode, and FIGS. 39 and 40 are schematic views showing the flow of the original when the manual original is conveyed.
[0245]
When a document is set on the manual document tray 14 (see FIG. 39A), manual paper feed processing (details will be described later) is started (FIG. 38 manual1), and the set document is conveyed to a predetermined position on the platen 3. (See FIG. 39 (b)).
[0246]
Thereafter, the scanner 204 is scanned, and a document image reading process is performed (FIG. 38 manual2). When the processing is completed, the document is discharged to the discharge tray 10 by a discharge process (details will be described later) (see FIG. 38 manual 3 and FIG. 40A).
[0247]
Thereafter, the process waits for the manual registration sensor 34 to detect the trailing edge of the original (manuald 4 in FIG. 38). When the detection is made, the manual original detection sensor 370 detects the presence or absence of the next original (in FIG. 38 manual 5). If there is a next original, the above-described operation is repeated (see FIG. 38 manual1 to manual5, FIG. 40B), and if there is no next original, a series of processing ends.
[0248]
Next, details of the operation of this mode will be described with reference to FIG. Here, FIG. 41 is a flowchart showing details of the operation in the manual feed mode.
[0249]
Normally, the paper discharge flapper solenoid 109 is off, and the paper discharge flapper 26 and the manual shutter 28 are held at the chain line positions in FIG. More specifically, the discharge flapper 26 is held at a position where the front end portion is lower than the platen 3, and the manual shutter 28 is held in a state of protruding into the document conveyance path.
[0250]
Therefore, when an operator sets a document on the manual document tray 14, the document is placed with the leading end of the manual shutter 28 being abutted against it.
[0251]
When the manual document detection sensor 370 detects that a document is set on the manual document tray 14, the paper discharge flapper solenoid 109 is turned on (ment 1 in FIG. 41), and the paper discharge flapper 26 and the manual shutter 28 have a link mechanism (not shown). To the position indicated by the solid line in FIG. Further, the paper discharge motor 104 is activated to rotate the manual paper feed roller 13 (ment 2 in FIG. 41), and the original P1 is conveyed in the manual conveyance path (L). During this time, the manual registration roller 11 is stopped.
[0252]
Thereafter, when the manual registration sensor 34 is turned on to detect the leading edge of the original (FIG. 41 ment3), the manual loop counter counted by the clock signal input from the paper discharge clock starts counting (FIG. 41 ment4), and the count ends. At that time, the drive of the discharge motor 104 is stopped (FIG. 41, ment 6 and ment 6). As a result, the original P1 conveyed by the manual paper feed roller 13 is stopped in a state in which a predetermined amount of loop is formed by abutting the leading edge of the original manual registration roller 11 and the original P1 is skewed. Correction is made.
[0253]
Thereafter, the paper discharge motor 104 and the belt motor 102 are started (FIG. 41 ment 7), and the manual paper feed roller 13, the manual registration roller 11 and the wide belt 7 are rotationally driven. As a result, the document P1 is transported from the manual transport path (L) to the document transport path (D).
[0254]
Simultaneously with the activation of the paper discharge motor 104 and the like, a size check counter that starts counting with a clock signal input from the belt clock is started (FIG. 41 ment 8), and when the passage of the trailing edge of the document is detected by turning off the manual registration sensor 34 (FIG. 41ment10), the count is stopped. Then, a size check process (FIG. 41 ment11) is performed based on the data.
[0255]
When it is confirmed that the trailing edge of the document has passed the manual paper feed roller 13 by turning off the manual registration sensor 34, the paper discharge motor 104 is turned off and the drive of the manual paper feed roller 13 is stopped (FIG. 41ment12).
[0256]
On the other hand, simultaneously with the start of the size check counter, the belt registration counter counted by the belt excitation clock is started (FIG. 41 ment9). When the counter finishes counting (FIG. 41 ment 13), the driving of the belt motor 102 (wide belt 7) is stopped (FIG. 41 ment 14), and the document P1 is located at a predetermined position on the platen 3 (the document leading edge is the first image tip position). (Position that matches R1).
[0257]
In this state, the scanner 204 is scanned and a document reading process is performed.
[0258]
The paper discharge flapper solenoid 109 is turned off (FIG. 41 ment 15), and the paper discharge flapper 26 and the manual shutter 28 are held at the chain line positions in FIG. 3 so that the next original can be set.
[0259]
When the document reading process is completed, the wide belt 7 is driven to rotate in the reverse direction, and the paper discharge roller 12 and the transport roller 19 are driven to rotate, so that the original P1 is discharged to the paper discharge tray 10. Since the paper discharge flapper 26 is held at the chain line position, the original is smoothly discharged without interfering with the flapper 26. As described above, the manual feed roller 13 is also rotated by the rotation of the paper discharge roller 12. However, since the manual shutter 28 is held at the chain line position, the feeding of the second original P2 is prevented. The
[0260]
On the other hand, when the manual document detection sensor 370 detects the next document, the above-described operation is repeated. That is, the paper discharge flapper solenoid 109 is turned on and the paper discharge motor 104 is activated. As a result, the paper discharge flapper 26 and the manual shutter 28 are moved to the solid line positions in FIG. 3 and the manual paper supply roller 13 is driven to rotate. The document is fed.
[0261]
Next, the effect of this embodiment will be described.
[0262]
According to the present embodiment, in the single-side original conveyance mode, the second feeding roller 9 conveys the subsequent original toward the image reading position while the scanner 204 is reading an image. Therefore, it is possible to shorten the time from the end of image reading by the scanner 204 to the start of the next image reading, to reduce the time required to read the images of a plurality of documents, and to improve the work efficiency.
[0263]
Further, according to the present embodiment, the distances L2 and L3 (the distances from the stop positions R2 and R3 of the scanner 204 to the nip portion of the second feeding roller 9) are longer than the length Lph in the document transport direction. It is set to be. Therefore, the scanner 204 reads the image of the document that is disengaged from the second feed roller 9 and is being conveyed alone by the wide belt 7, and the document and the second feed are read during image reading. The engagement with the feed roller 9 is not released. Further, as described above, the succeeding document is transported by the second feeding roller 9 while the image of the preceding document is being read, but the second feeding roller 9 finishes transporting the succeeding document and The disengagement timing is when the scanner 204 is not reading an image (that is, after reading the image of the preceding document and before reading the image of the subsequent document). As described above, according to the present embodiment, while the scanner 204 is reading an image, a document (a document that is a target of image reading and a document subsequent to the document) and a feed are supplied. Since the engagement with the roller 9 is not disengaged, the wide belt 7 can convey the document at a constant speed, and can maintain good image reading accuracy.
[0264]
Furthermore, according to the present embodiment, by changing the stop position of the scanner 204 according to the size information, the distance from the stop position of the scanner 204 to the second feeding roller 9 is always (regardless of the document size). The length is longer than the length Lph in the document conveyance direction. Therefore, it is possible to maintain good image reading accuracy regardless of the size of the document to be conveyed.
[0265]
Further, the distances L2 and L3 (the distances from the stop positions R2 and R3 of the scanner 204 to the second feeding roller 9) are set to be longer than the length Lph in the document transport direction as described above. However, by minimizing the difference between these distances L2 and L3 and the length Lph, the document transport length (movement amount) can be reduced, the work efficiency can be improved, and the apparatus can be downsized. Furthermore, the reading image quality can be improved. In this case, by changing the distance from the stop position of the scanner 204 to the second feeding roller 9 according to the document size, the work efficiency and the read image quality are improved regardless of the size of the document to be conveyed. Can do.
[0266]
On the other hand, the wide belt 7 temporarily stops the conveyance of the document before image reading by the scanner 204 is started, and conveys the document in response to a conveyance start signal from the scanner 204 side (that is, the apparatus main body 1). To resume. Therefore, even if there is some inconvenience on the apparatus main body 1 side (for example, when it takes time to transfer image data of a preceding original document), the conveyance of the original is resumed after the inconvenience is resolved. Therefore, image reading can be performed properly.
[0267]
On the other hand, according to the present embodiment, the start timing of the second feeding roller 9 and the start timing of the wide belt 7 are made different so that the inter-paper distance before document transport and the inter-paper distance after document transport. It is possible to achieve both miniaturization and image quality maintenance. Further, even if the distance between sheets is minimized during document conveyance, image reading is not affected, and as a result, the apparatus can be minimized.
[0268]
On the other hand, it is possible to minimize the operation of the scanner 204 by changing the stop position (standby position) of the document before image reading in accordance with the size of the document, and it is possible to produce a cheap and highly reliable system. Can be improved.
[0269]
On the other hand, while waiting for a document, the interval between the document whose image is to be read and its preceding document (the document whose image reading has already been completed) is different from the interval between the document whose image is to be read and its subsequent document. In this case, the apparatus can be reduced in size.
[0270]
In the above-described embodiment, the document size is determined only by the size in the document transport direction by the document trailing edge detection sensor 41, but not only the document trailing edge detection sensor 41 but also the paper width detection sensor 44. It may be used to determine the document size.
[0271]
【The invention's effect】
As described above, according to the present invention, since the second original is conveyed by the second conveying unit after the image being read while the image reading unit is performing image reading, the image reading is performed. It is possible to shorten the time from when the means finishes image reading to when the next image reading starts, shorten the time required to read the images of a plurality of documents, and improve work efficiency.
[0272]
On the other hand, according to the present invention, the distance from the stop position of the image reading unit to the first conveying unit is set to be longer than the length in the document conveying direction, and the image reading unit includes the first reading unit. The image of a document in a state where it is disengaged from the conveying means and being conveyed by the second conveying means is read. Further, the subsequent original is conveyed by the second conveying means while the image reading means is reading the image as described above, and the second conveying means conveys the subsequent original. The timing of the end and disengagement from the subsequent document is during the time when the image reading unit is not performing image reading (that is, after reading the image of the preceding document and before reading the image of the subsequent document). As described above, according to the present invention, while the image reading unit is reading an image, the original (the original to be read and the original subsequent to the original) and the first Since the engagement with the conveying unit is not disengaged, the second conveying unit can convey the document at a constant speed and can maintain good image reading accuracy.
[0273]
In this case, by changing the stop position of the image reading unit according to the size information, it is possible to maintain good image reading accuracy regardless of the size of the document to be conveyed.
[0274]
On the other hand, the second conveying unit temporarily stops conveying the document before the image reading by the image reading unit is started, and resumes conveying the document upon receiving a signal from the image reading unit side. In such a case, even if there is any inconvenience, the image can be read properly by restarting the conveyance of the document after the inconvenience is resolved.
[0275]
On the other hand, the distance between the paper before the document conveyance and the distance between the paper after the document conveyance can be made variable by activating the first conveyance means and the second conveyance means at different timings. Both maintenance can be achieved. Further, even if the distance between sheets is minimized during document conveyance, image reading is not affected, and as a result, the apparatus can be minimized.
[0276]
On the other hand, it is possible to minimize the operation of the image reading means by changing the stop position (standby position) of the document before image reading according to the size of the document. Productivity can be improved.
[0277]
On the other hand, while waiting for a document, the interval between the document whose image is to be read and its preceding document (the document whose image reading has already been completed) is different from the interval between the document whose image is to be read and its subsequent document. In this case, the apparatus can be reduced in size.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing the overall configuration of an image forming apparatus according to the present invention.
FIG. 2 is a cross-sectional view showing a detailed structure of a printer unit.
FIG. 3 is a detailed sectional view showing the structure of an ADF.
FIG. 4 is a diagram showing the structure of a paper feed roller and the like disposed at the left end of the document tray, the operation thereof, and the maximum raised position of the paper feed roller.
FIG. 5 is a diagram illustrating a maximum lowering position of a sheet feeding roller.
FIG. 6 is a component diagram showing the structure of a swing arm and the like.
FIG. 7 is a plan view showing the structure of a paper feed roller and the like.
FIG. 8 is a diagram showing a positional relationship between a document and a scanner when reading an image.
FIG. 9 is a diagram illustrating a positional relationship between a document and a scanner during image reading.
FIG. 10 is a block diagram illustrating a circuit configuration of a control circuit.
FIG. 11 is a flowchart showing an outline of the operation of the image forming apparatus.
FIG. 12 is a flowchart showing an outline of an operation when a half-size single-sided original is conveyed.
FIG. 13 is a schematic diagram illustrating the flow of a document when a half-size single-sided document is conveyed.
FIG. 14 is a schematic diagram illustrating a flow of a document when a half-size single-sided document is conveyed.
FIG. 15 is a flowchart showing details of an action when a half-size original document is conveyed.
FIG. 16 is a diagram illustrating a state in which a paper feed roller is in contact with a document.
FIG. 17 is a flowchart for explaining a pickup DOWN process of a paper feed roller.
FIG. 18 is a diagram for explaining a retracted position of a paper feed roller.
FIG. 19 is a flowchart for explaining separation processing.
FIG. 20 is a flowchart for explaining size check processing;
FIG. 21 is a flowchart for explaining the document reading process.
FIG. 22 is a flowchart for explaining a pickup UP process of a paper feed roller.
FIG. 23 is a flowchart for explaining a paper discharge process.
FIG. 24 is a flowchart showing an outline of an operation when a large-size single-sided original is conveyed.
FIG. 25 is a schematic diagram illustrating the flow of a document when a large-size single-sided document is conveyed.
FIG. 26 is a schematic diagram illustrating the flow of a document when a large-size single-sided document is conveyed.
FIG. 27 is a flowchart showing an outline of an operation when a half-size double-sided original is conveyed.
FIG. 28 is a schematic diagram illustrating the flow of a document when a half-size duplex document is conveyed.
FIG. 29 is a schematic diagram illustrating a flow of a document when a half-size duplex document is conveyed.
FIG. 30 is a schematic diagram illustrating the flow of a document when a half-size duplex document is conveyed.
FIG. 31 is a schematic diagram illustrating the flow of a document when a half-size duplex document is conveyed.
FIG. 32 is a flowchart showing details of an operation when a half-size double-sided original is conveyed.
FIG. 33 is a flowchart for explaining reversal processing in a duplex original conveyance mode.
FIG. 34 is a schematic diagram illustrating a flow of a document when a large-size double-sided document is conveyed.
FIG. 35 is a schematic diagram illustrating a flow of a document when a large-size double-sided document is conveyed.
FIG. 36 is a schematic diagram illustrating the flow of a document when a large-size double-sided document is conveyed.
FIG. 37 is a schematic diagram illustrating the flow of a document when a large-size double-sided document is conveyed.
FIG. 38 is a flowchart showing an outline of the operation in the manual feed mode.
FIG. 39 is a schematic diagram illustrating a flow of a document when a manual document is conveyed.
FIG. 40 is a schematic diagram illustrating a flow of a document when a manual document is conveyed.
FIG. 41 is a flowchart showing details of the operation in the manual feed mode.
FIG. 42 is a diagram for explaining a document conveyance path and the like.
[Explanation of symbols]
2 ADF
3 Platen
4 Document tray
5 Paper feed roller
6 Separation belt
7 Wide belt (second conveying means)
8 Separation transport roller
9 Second feeding roller (first conveying means)
16 First feed roller
17 First reverse roller
18 Second reversing roller
30 Separate sensor
36 Driving roller
37 Turn roller
40 Document set detection sensor
41 Document trailing edge detection sensor (document size detection means)
44 Paper width detection sensor
46 Oscillation position sensor
51 Lifting arm
52 Upper separation guide plate
53 Swing arm
56 Positioning pin
59 Separate guide plate
100 separation motor
100b Separate clock sensor
103 Swing motor
200 Reader section
204 Scanner (Image reading means)
G Image forming apparatus
P manuscript
S Separator
E, F, G Reverse feed path

Claims (7)

A first conveying unit configured to convey a plurality of documents continuously; and further conveying a document that is disposed downstream of the first conveying unit in the document conveying direction and is conveyed by the first conveying unit. Image forming means comprising: a second transporting unit configured to read; and an image reading unit configured to read an image of a document transported by the second transporting unit while being stopped at a position facing the second transporting unit. In the device
The distance from the stop position of the image reading unit to the first conveying unit is set to be longer than the length in the document conveying direction, and the image reading unit is engaged with the first conveying unit. Read the image of the original that is unloaded and being conveyed by the second conveying means,
The first transport unit transports a document subsequent to the document being scanned while the image scanning unit is scanning an image, and the document while the image scanning unit is not scanning an image. To finish the transport of the paper and disengage the original,
An image forming apparatus. A document size detecting means for detecting the length of the document in the conveyance direction, and a reading position changing means for changing the stop position of the image reading means,
In accordance with the size information from the document size detection unit, the reading position changing unit makes the distance from the stop position of the image reading unit to the first transport unit longer than the length in the document transport direction. Changing the position of the image reading means; and
The image reading unit reads an image of a document in a state of being disengaged from the first conveying unit and being conveyed by the second conveying unit;
The image forming apparatus according to claim 1. The second conveying unit temporarily stops conveying the document before the image reading by the image reading unit is started, and resumes conveying the document in response to a signal from the image reading unit;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. Activating the first conveying means and the second conveying means at different timings;
The image forming apparatus according to claim 3. The second conveying unit changes a position where the document is stopped according to size information from the document size detecting unit;
The image forming apparatus according to claim 3. During document standby, the interval between the document for image reading and the document for which image reading has already been completed is different from the interval between the document for image reading and its subsequent document.
The image forming apparatus according to claim 3. The interval between the document for image reading and the document for which image reading has already been completed is wider than the interval between the document for image reading and the subsequent document.
The image forming apparatus according to claim 6.

Images