JPH04125259A - Feeding method for sheet document - Google Patents

Abstract

PURPOSE:To carry a sheet document while being brought close to a sheet document running ahead by feeding a fist and a second sheet document at equal speeds when a space between the downstream end of the second sheet document in the feeding direction after it is turned over and the upstream end of the first sheet document in the feeding direction to be suspended, comes up to a specified length set in advance. CONSTITUTION:When a space between the downstream end of a second sheet document D in the feeding direction after it is turned over and the upstream end of a first sheet document D in the feeding direction to be suspended, comes up to a specified length set in advance, the first and second sheet documents D are fed at equal speeds. The specified length set in advance is determined in such a way that the upstream end of the second sheet document in the feeding direction after it is turned over, is suspended at a point when it passes through the branch position of its carrying path at the time when the first sheet document is suspended over a document read surface 5. This thereby enables the first and second sheet documents D to be carried over to the document read surface 5 in state where both of the documents D come sufficiently close to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to a document feeding device installed in a copying machine, for example, in which a plurality of sheet documents are continuously fed onto a document reading surface for reading exposure. The present invention relates to a method of feeding sheet-like originals that is particularly advantageously implemented.

2. Description of the Related Art For the convenience of operators, copying machines have traditionally been equipped with document feeding devices that automatically and sequentially feed a plurality of sheet documents onto a document reading surface. Documents to be copied are placed on a placing member and fed sequentially, for example from the lowest position in the stacking direction.

On the document reading surface, document images are sequentially fed by a conveying belt facing the inside of the machine, and are read and exposed by, for example, an optical reading device, and then cooperated with a copying machine to make a double-sided copy or a single-sided copy. etc. have been realized.

FIG. 7 is a sectional view showing a simplified configuration of a conventional document feeding device 201. As shown in FIG. The originals 'd to be copied are stacked and placed on the holder 1 member 206. On the downstream side of the placing member 206 in the paper feeding direction 207, a paper feeding means 210 is provided that sequentially feeds the originals d one by one. The paper feeding means 210 is
For example, it consists of an adsorption conveyance means 211 arranged below with respect to the mounting member 206, and an exhaust duct 212 arranged above with respect to the mounting member 206.

The suction conveyance means 211 is made up of an endless belt 215 having a large number of openings wrapped around two drive rollers 213214 whose axes are perpendicular to the paper feeding direction 207. The drive rollers 213, 214 are driven by a motor m1.

An intake duct 216 is disposed on the inner side of the belt 215, and by driving an intake fan (not shown), suction force is applied from the intake duct 216 via the belt 215, and the stacks are stacked. The lowest document of the document d is attracted to the belt 215. Therefore, by driving the driving rollers 213 and 214 clockwise, the lowest document d in the stacking direction is sequentially moved to the sheet feeding direction 2.
Paper is fed toward 07.

An air flow is ejected from the nozzle of the exhaust duct 212 toward the downstream end of the document d on the lower side in the stacking direction in the paper feeding direction.

As a result, the downstream end is handled one by one, and the suction and conveyance means 211 reliably feeds one sheet at a time. The document d fed by the paper feeding means 210 is transported to the transport path 240 and the reversing means 218 .

The reversing means 218 includes a transport path 222, 229, a pair of transport rollers 220, 221, 230, and a direction switching claw 2.
28, and motor m2. m3. The conveyance path 240 includes a first conveyance path 222 formed to extend in a clockwise direction and a second conveyance path 229 formed to extend in a counterclockwise direction in the vicinity of the direction switching claw 228.
It branches into

A conveyance roller 220221 is provided on the first conveyance path 222, and can be driven to rotate in forward and reverse directions by the driving force from the motor m2. Further, the second conveyance path 229 is provided with a conveyance roller 230, which is driven by the driving force from the motor m3. The direction switching pawl 228 is driven by, for example, a solenoid. For example, when the solenoid is demagnetized, a path for transporting the document d from the transport path 240 toward the first transport path 222 is opened.

On the other hand, when the solenoid is energized, a passage for conveying the document d from the first conveyance path 222 to the second conveyance path 229 is opened.

The first conveyance path 222 and the second conveyance path 229 merge near the upstream end of the feeding direction 223 with respect to the transparent plate 205 that constitutes the document reading surface. Therefore, the document d that has been conveyed through the reversing means 218 based on each set copy mode is conveyed onto the transparent plate 205 along the feeding direction 223.

Above the transparent plate 205 are two rollers 22.4a and 224 whose axes are parallel to the width direction of the document d being fed.
b is arranged along the feeding direction 223, and a plurality of endless belts 226 are wound around it. The roller 224a is
Driven by motor m4. A plurality of press rollers 225a to 225d are arranged along the feeding direction 223 on the inner surface side of the belt with respect to the understretching portion of the belt 226. These press rollers 225a to 225dj,
t, the belt 226 is pressed toward the transparent plate 205 to avoid slack in the tension of the belt 226 and to prevent the document d fed between the belt 226 and the transparent plate 205 from floating.

The document d conveyed on the transparent plate 205 by the belt 226 is conveyed to a reading position on the transparent plate 205. The document image of the document d conveyed to the reading value 1 is presented to the inside of the machine, and the document image is optically scanned by an optical system that is an optical reading means provided inside the copy machine. Then, a reading exposure operation of the original image is performed.

While the previously fed original is being read and exposed, the subsequent original is preliminarily fed. The subsequent original is waiting just in front of the transparent plate 205.

When the reading exposure operation of the original image is completed, the belt 226 is rotated again, and the original d is transported to the transport path 236,
It is further conveyed by conveyance rollers 234 and 235, and then stored again at the uppermost position in the stacking direction of the document d stacked on the holder 1 member 206.

Problems to be Solved by the Invention In the above-described document feeding device 201, the transport roller 230 and the roller 224a are each driven by separate motors m3. m4
driven by. Furthermore, since the conveyance speed of the conveyance roller 230 is slower than the conveyance speed of the belt 226, even if the document d is pre-fed, the distance between the documents on the transparent plate 205 will not become shorter. It was not possible to reduce the time required to convey the sheet-like original onto the original reading surface.

An object of the present invention is to make it possible to transport multiple sheets of originals by using a simple control method to sufficiently close the transport interval between the preceding sheet-like original and the following sheet-like original, and by realizing sufficient preliminary paper feeding. It is an object of the present invention to provide a method for feeding a sheet-like original document, which can significantly reduce the time required for conveying it onto a reading surface.

Means for Solving the Problems The present invention reverses the feeding direction after conveying a plurality of sheet-like originals fed from a loading member 1 to one of the branching conveyance paths, and transfers them to the other branching conveyance path. In the method of feeding sheet-like originals in which the sheet-like original is successively conveyed to the original reading surface facing the optical reading means, the upstream end of the preceding first sheet-like original in the feeding direction after being reversed is on the conveying path. When it passes the branching position, the conveyance of the first sheet-shaped original is stopped, the feeding direction of the following second sheet-shaped original is reversed, and the following third sheet-shaped original is further conveyed to the vicinity of the branching position. When the distance between the downstream end in the feeding direction of the second sheet-like document after being reversed and the upstream end in the feeding direction of the first sheet-like document to be stopped reaches a predetermined length, the first and second sheets This is a method of feeding a sheet-like original, which is characterized by feeding a sheet-like original at a constant speed.

According to the present invention, the sheet-like original fed from the mounting member is first conveyed to one of the branched conveyance paths, the feeding direction is reversed, and the document is transferred through the other branched conveyance path. It is conveyed onto the reading surface. The above-described conveyance operation is performed sequentially over a plurality of sheet-like originals, and in this way, the subsequent sheet-like original is conveyed in succession to the preceding sheet-like original.

In the present invention, when the upstream end in the feeding direction after reversing of the preceding first sheet-like original passes through a branch position of the transport path, the conveyance of the first sheet-like original is stopped, and the subsequent second sheet By reversing the feeding direction of the original sheet, the distance between the first sheet original and the second sheet original can be made sufficiently close. Further, while the feeding direction of the second sheet original is being reversed, the following third sheet original is transported to the vicinity of the branching position of the transport path.

Thereafter, when the distance between the downstream end in the feeding direction of the second sheet original after being reversed and the upstream end in the feeding direction of the stopped first sheet original reaches a predetermined length, the first and second sheets Feeds the original at a constant speed.

The predetermined length is a point (first
The length is selected so that the sheet document stops at the point where the original sheet stopped.

Therefore, the first and second sheet documents can be conveyed onto the document reading surface while keeping them sufficiently close to each other.
This prevents the gap between each sheet-like document from widening due to the difference in conveyance speed between the first and second sheet-like documents as in the prior art.

Further, while the second sheet original is stopped, that is, while the first sheet original is being read and exposed, the feeding direction of the third sheet original is reversed, and the third sheet original is A sheet-like original following the original is transported to a branching position of the transport path. Thereafter, such operations are performed continuously.

Therefore, it is possible to carry out preliminary paper feeding in which the following sheet-like original is kept sufficiently close to the preceding sheet-like original and then on standby, and as a result, after the reading exposure of the preceding sheet-like original is completed, the original reading surface of the following sheet-like original is The upward conveyance time can be significantly shortened, and the copying time can be shortened.

Embodiment FIG. 1 is a sectional view showing a simplified configuration of a document feeding device 1 which is an embodiment of the present invention, and FIG. 2 is a transfer type electrostatic copying machine equipped with the document feeding device 1. FIG. 2 is a sectional view showing a simplified configuration of No. 2;

A transparent plate 5 made of a material such as hard glass is disposed on the upper side surface 3 of the copying machine body 2. As shown in FIG. The document feeding device 1, in which the transparent plate 5 forms a document reading surface, is installed above the transparent plate 5, and is mounted, for example, on the upper side surface 3 of the body, between the rotating shafts 4 so as to be freely angularly displaceable. When the original is not fed by the original feeding device 4 (for example, when the original is a book), the device 1 is angularly displaced around the rotation axis 4 and the original is placed on the transparent plate 5. The original is placed with the original image facing inside the machine, and the copying operation is performed while being pressed and fixed.

Generally, as shown in FIGS. 1 and 2, the document feeding device 1 is arranged to cover a transparent plate 5, and has sheet-like sheets stacked on a loading member 6. The originals are automatically fed one after another to the reading position 5a on the transparent plate 5, and the images of the originals are presented. The presented original image is optically scanned by an optical reading means provided in the copying machine 2, and a reading exposure operation of the original image is performed. The document tray from which the document image has been read is again stored in the placement member 6. The conveyance is carried out sequentially for the originals stacked on the stacker 1 member 6, and is circulated among the originals depending on the number of copies required, thus making one-sided copying or double-sided copying on the recording paper P. Execute.

The configuration of the document feeding device 1 will be described below with reference to FIG.

Documents to be copied are placed on the placement member 6 in a stacked manner. The placement member 6 is provided with a pair of alignment plates 8 that face each other in the width direction perpendicular to the paper feeding direction 7 . The alignment plates 8 move toward or away from each other along the mutually opposing directions according to the widthwise dimensions of the stacked document trays, thereby aligning both ends of the document trays in the width direction. In other words, the stacked originals are
Regardless of the width direction dimension, the width direction center position is constant. Further, a trailing edge alignment plate 9 is disposed at the upstream end of the stacked originals in the paper feeding direction 7 to align the upstream ends of the stacked originals in the paper feeding direction. be done.

On the downstream side of the mounting member 6 in the paper feeding direction, there is provided a paper feeding means 1o for sequentially feeding documents one by one. The paper feeding means 10 includes, for example, a suction conveyance means 11 disposed below with respect to the placing member 6, and an exhaust duct 12 disposed above with respect to the placing member 6.The suction conveyance means 11 is , an endless bell (15) having a large number of openings is wound between two drive rollers (13, 14) whose axes are perpendicular to the paper feeding direction (7).
3°14 is driven by motor M1. An intake duct 16 is arranged on the inner side of the belt 15.
By driving a suction fan (not shown), a suction force is applied to the suction duct 16 via the belt 15, and the lowest document in the stacked document tray is pulled onto the belt 15.
5 is attracted. Therefore, the drive roller 13,
14 clockwise (see FIG. 1), the lowest originals in the stacking direction are sequentially fed in the paper feeding direction 7.

An air flow is ejected from the nozzle of the exhaust duct 12 toward the downstream end of the document tray on the lower side in the stacking direction in the paper feeding direction. As a result, the downstream end is handled one by one, and the suction and conveyance means 11 reliably feeds one sheet at a time.

In this way, the stacked documents can be sequentially fed by the paper feeding means 10 from the lower side in the stacking direction. Note that the oval shape of the paper feeding means 10 is not limited.

The document fed by the paper feeding means 10 is conveyed to a conveying path 40 and a reversing means 18 via conveying rollers 17 . Further, on the downstream side of the mounting member 6 in the paper feeding direction,
For example, a first transport detector S1 including a light emitting element Sla and a light receiving element S1b is provided. The reliable feeding of the document one by one is detected by the first conveyance detector S1.

In FIG. 1, the reversing means 18 includes a substantially cylindrical support tube 1
Formed on the outer surface of 9. The conveyance path 40 having the conveyance port 17 is a first conveyance path 22 extending in a clockwise direction (see FIG. 1) on the outer surface of the support cylinder 19.
and a second conveyance path 29 extending counterclockwise. Conveyance rollers 20 and 21 are provided on the first conveyance path 22 to press and convey the document along the outer surface of the support cylinder 19, and are rotated in forward and reverse directions by driving force from a motor M2 via a clutch CLT3 (not shown). Can be driven.

Further, on the first transport path 22, a second transport detector S2 consisting of, for example, a light emitting element S2a and a light receiving element S2b is provided.
is provided. The second transport detector S2 detects the first
The conveyance state of the document being conveyed through the conveyance path 22 is detected, and the timing and direction of rotation of the conveyance rollers 20 and 21 are controlled.

Further, the second conveyance path 29 is provided with a conveyance roller 30 that presses and conveys the document along the outer surface of the support tube 19. A drive shaft of the conveyance roller 30 is connected to a motor M3 via a clutch CLTI. Therefore, by controlling the connection/disconnection of the clutch CLTI, the rotation of the conveyance roller 3o in one direction is stopped by 7'. Further, on the two second transport paths, for example, a light emitting element S
3a and a light receiving element S3b. The third conveyance detector S3 detects the conveyance state of the original document conveyed on the second conveyance path 29, and controls the rotation timing of the conveyance roller 30 and the like.

Further, a direction change type 28 driven by a solenoid SQL 1 is disposed at a branch point of the first conveyance path 22 and the second conveyance path 29. For example, solenoid 5C)
When Ll is demagnetized, a path for conveying the document from the conveyance path 40 toward the first conveyance path 22 is opened, as shown by the solid line in FIG. On the other hand, solenoid SQL
1, the direction changing die 28 is angularly displaced to the position shown by the dotted line, and a path for conveying the document from the first conveyance path 22 toward the second conveyance path 29 is opened.

The solenoid 5OLI is switched and controlled, for example, based on the detection result of the second conveyance detector S2.

The sides of the first conveyance path 22 and the second conveyance path 29 opposite to the direction changing mold 28 merge near the upstream end of the feeding direction 23 with respect to the transparent plate 5.

Therefore, the document sheet conveyed through the reversing means 18 based on each copy mode set as described later is
3 onto the transparent plate 5.

Above the transparent plate 5, two rollers 24a and 24b having axes parallel to the width direction of the document to be fed are disposed along the feeding direction 23, and a plurality of endless belts 26 is wrapped around it. The drive shaft of the roller 2-4 is connected to the motor M3 via a clutch CL'T2. Therefore, by controlling the connection/disconnection of the clutch CLT2, the conveyance drive state of the belt 26 is switched. A plurality of (four in this embodiment) press rollers 25a to 25d are arranged in this order along the feeding direction 23 on the inner surface side of the belt with respect to the undercarriage portion 26a of the belt 26. The press rollers 2-5 a to 25d
presses the belt 26 toward the transparent plate 5 to avoid loosening the tension of the belt 26, and
- Prevents the original paper fed to the transparent plate from floating.

Further, due to the level difference between the tension position of the belt 26 on the roller 24a and the tension position of the belt 26 on the press roller 25a on the most upstream side in the feeding direction, the transparent plate 5 is
A gap 27 is formed near the 3 upstream side. That is, on the upstream side in the feeding direction with respect to the press roller 2'5a, the belt 2-6 is
is inclined at a constant angle θ with respect to the transparent plate 5.

Said time IIN! 27 is the first inverting means 18 described above.
Continuing with the conveyance path 22 and the second conveyance path 29, therefore, in the gap 27, even when the belt 26 is stopped, the conveyance force of each conveyance roller 20, 21, 30 in the reversing means 18 is reduced. This allows the original document to enter and be transported.

The document conveyed on the transparent plate 5 by the belt 26 is conveyed to the reading position 5a on the transparent plate 5. The reading position 5a refers to the feeding direction 2 with respect to the transparent plate 5.
This corresponds to the position where the downstream end of the document to be fed in the feeding direction comes into contact with the abutting piece 32 protrudingly disposed near the third downstream end. In this way, the document conveyed to the reading value f5a is
The original image is presented to the inside of the machine, and the original image is optically scanned by an optical system 31, which is an optical reading means provided inside the copying machine 2, and the original image is read and exposed. An action is taken.

While the previously fed original is being read and exposed, the subsequent original is preliminarily fed. The subsequent document is placed in the gap 2.
7, the preliminary paper feeding can be completed and the machine can stand by. The distance from the vicinity of the press roller 25a, where the downstream end of the prefed document in the feeding direction reaches, to the contact piece 32 is sufficiently large enough to allow the document to be fed, regardless of its size. It is selected appropriately to avoid collision between the preceding original and the pre-fed subsequent original.

When the reading exposure operation of the original image is completed, the abutment piece 32 is angularly displaced under the control of the solenoid 5QL2, and the path from the reading position 5a to the transport path 36 is opened.

At the same time, the belt 26 is rotated again, and the conveying roller 33
The original document is conveyed through the conveyance path 36 by ~35,
Thereafter, the document is stored again at the uppermost position in the stacking direction of the originals stacked on the placement member 6.

On the conveyance path 36, for example, a discharge detector 84 including a light emitting element S4a and a light receiving element S4b is arranged. The discharge detector S4 detects the conveyance state of the document conveying through the conveyance path 36, and the solenoid 5QL2 is activated.
Controls the drive timing, etc. Further, near the placement member 6, a one-cycle detector S5 is provided to detect one cycle of conveyance of the stacked documents. The detector S5 includes, for example, an actuating member that comes into contact with the top of the stacked document sheets, and as the document sheets are fed, the document sheets are placed between the actuating member and the placing member 6. If it is detected optically, for example, that there is no intervention, it can be determined that all the documents have been fed and one cycle has been completed.

As described above, the optical system 31 performs the reading exposure operation on the original image presented to the reading position 5a. In the optical system 31, a first moving body 43 including a light source 41 such as a halogen lamp and a reflecting mirror 42 moves back and forth along a horizontal direction 44 with respect to the reading position 5a, and irradiates the presented document with light. The reflected light is reflected by the reflecting mirror 46 of the second moving body 45.
．． 47, the image is formed on a right cylindrical photoreceptor 51 which is rotated in the direction of arrow 50 through a zoom lens 48 and a reflecting mirror 49. Note that the second moving body 45 is also driven to run in the same direction as the first moving body 43 at half the scanning speed, and the optical path length of the reflected light is kept constant.

The surface of the photoconductor 51 is charged in advance by a charging corona discharger 52, and the photoconductor 51 is charged by the image formation.
An electrostatic latent image corresponding to the original image is formed thereon. The I# recorded static latent image is converted into an S toner image by the developing device 53, and is transferred onto one surface of the recording paper P by the transfer corona discharger 54.

The recording paper P is stored in a paper feed cassette 55 in advance, and is conveyed along a conveyance path 57 that includes a pair of registration rollers 56, and guided to a transfer area 58 where transfer is performed. A clutch CL (not shown) is attached to the rotation shaft of the registration roller 56.
A power transmission means is connected via T4. By controlling the connection/disconnection of the clutch CLT4 based on the control of the timing for transporting the document in the document feeding device N1, the recording paper P is transported by the registration roller 56 with respect to the toner image on the photoreceptor 51. You can match the timing. The recording paper P onto which the toner image has been transferred by the transfer corona discharger 54 is guided to the fixing device 60 through the conveying means 59 and is fixed thereon.

After the fixing, the recording paper P is conveyed in a reverse direction by a recording paper reversing means 61, and is temporarily stored in an intermediate tray 63 via a conveyance path 62. Recording paper P in intermediate tray 63
is again guided to the transfer area 58 by the conveying means 64 and the registration rollers 56, and the toner image is transferred to the other surface of the recording paper P. The recording paper P on which the transfer has been completed is discharged to an output tray 66 outside the machine via five conveyance means, a fixing device 60, and a conveyance path 65. In this way, the original images of the corresponding original sheets are copied onto both the front and back surfaces of the corresponding recording paper P. Note that when copying is performed only on one side, the recording paper P that has been copied on one side is not ejected to the intermediate tray 63 but is ejected to the ejection tray 66. For example, recording sheets P having mutually different sizes are selectively conveyed to the transfer area 58 from the paper feed cassettes 55, 67 to 69.

FIG. 3 is a block diagram showing the electrical configuration of the document feeding device 1 and the copying machine 2. As shown in FIG. Motors Ml, M2 . M3 . . . is a clutch CLTI in the motor drive circuit 110 that controls the drive timing of the conveyance roller 30 and the belt 26.

CLT2. CLT3. ... is the clutch drive circuit 11
1, solenoids 5OLI, 5QL2. ... are respectively connected to the solenoid drive circuit 112. These drive circuits 1
Control elements such as 10 to 112 and a DC power source 114 used for document transport control, recording paper transport control, and control of the copying process are connected to an interface circuit (I, , 10) 113.
connected to.

This interface circuit 113 includes various detectors S1. S21. is connected, and further microcomputer (CPLJ) 120
is connected. The signal from the detector is given to the microcomputer 120, and the microcomputer 120
Then, calculation processing corresponding to this signal is performed, and each drive port 1
110 to 112 are the drive control signals to the interface circuit 81
13.

A ROM (read only memory) 121 and a RAM (random access memory) 122 are connected to the microcomputer 120 . The microcomputer 120 performs control operations based on a control program stored in the ROM 121 while using the storage area of the RAM 122 as a work area.

The interface circuit 113 is connected to the optical system 31 via a drive circuit 115 and energizes the light source 41 and sends display control signals to each display section 118 of the operation panel 116 via a display drive circuit 117. It is also connected to a key 119 for operation.

The conveyance state of the document tray in the document feeding device 1 in each copy mode will be described below.

FIG. 4(1) shows the conveyance state of a single-sided document printer. For convenience, the positions of the mounting member 6, the transparent plate 5, and the reversing means 18 are shown in a simplified manner in FIG. 4(1). Single-sided originals to be copied are stacked and placed on the placing member 6 with the original image facing upward. By fixing the direction changing mold 28 as shown by the solid line in FIG. .

The document that has passed through the first conveyance path 22 is conveyed to the reading position 5a through a gap 27 formed on the upstream side in the feeding direction with respect to the transparent plate 5. In this manner, the front and back surfaces on the placement member 6 are reversed by passage of the reversing means 18, and the document is brought to the reading position 5a, where the document image is presented.

After the optical system 31 performs a reading exposure operation on the presented original image, the belt 26 is driven again, and the uppermost original in the stacking direction is stacked on the mounting member 6 via the transport path 36. It will be re-stored in. In this way, the original image of the single-sided original transported to the reading position 5a is read, and in cooperation with the copying machine 2, one-sided copying and double-sided copying onto the recording paper P are realized.

When a plurality of originals are sequentially fed to the reading position 5a, the following original is pre-fed in advance to the original that is being fed in advance, so that the reading exposure is sufficient for the preceding original that is being exposed. It is necessary to wait in a nearby position. Since a gap 27 is formed on the transparent plate 5 continuously to the first conveyance path 22, the subsequent document is kept in reserve until its downstream end in the feeding direction reaches the vicinity of the press roller 25a in the gap 27. Paper can be fed, and the document can be kept sufficiently close to the preceding document.

FIG. 4 (2) shows the conveyance state of a double-sided document tray.0 For a double-sided document tray that has document images to be copied on both the front and back surfaces, the number of pages increases from the upper side to the lower side in the stacking direction. They are stacked so as to be aligned and placed on the mounting member 6. The original document fed from the lowest position in the stacking direction is conveyed to the reversing means 18. The direction changing air 28 is first set as shown by the solid line in FIG. 1, and as a result, the transported document is transported toward the first transport path 22 and the gap 27.

Paper feeding direction 7 of the original document transported to the first transport path 22
When it is detected, for example, by the second conveyance detector S2 that the downstream end has passed the direction changing wind 28, the first
The rotation directions of the conveyance rollers 20 and 21 on the conveyance path 22 are driven in reverse, and the direction changing air 28 is also switched to the position shown by the dotted line in FIG. Therefore, the feeding direction of the original document is reversed, and the document is transported from the first transport path 22 to the second transport path 29, and is again transported to the reading position 5a on the transparent plate 5 through the gap 27.

In this way, at the reading position 5a, the lower side surface is presented with respect to the front and back surfaces when placed on the placement member 6.

Therefore, the lower surface is read exposed, and then
Through the conveyance path 36, the front and back surfaces are reversed and the document stacked on the placement member 6 is re-stored in the uppermost position in the stacking direction. With respect to the originals stacked on the placement member 6, the lower surface of each original is read and exposed by one cycle of the conveying operation, and the lower surface of each original is placed on the intermediate tray 63 in the copying machine 2. The recording sheets P on which each copy has been made are stacked and stored.

Subsequently, the conveyance operation shown in FIG. 4(2) is performed again on the re-stored and stacked document sheets. As a result, the upper surface, which has not yet been read, is presented to the reading position 5a. The original image on the upper surface is read and exposed, and is copied onto the other uncopied surface side of the recording paper P fed from the lowest position in the stacking direction of the intermediate tray 63, and thus the recording paper on which double-sided copying has been completed. P is completed sequentially. The original document whose upper surface has been read and exposed is turned over again through the conveyance path 36, and placed on the mounting member 6.
The documents stacked in the stack are re-stored at the top in the stacking direction. In this way, the original document after two circulations returns to its original state before copying.

Even when transporting the double-sided document, preliminary paper feeding is performed to shorten the copying time as described above, and the subsequent document is placed in a standby position sufficiently close to the preceding document that is being exposed for reading. It is necessary to do so. A gap 27 is provided on the transparent plate 5 that is continuous with the first conveyance path 22 and the second conveyance path 29, so that the downstream end of the document passing through the second conveyance path 29 in the feeding direction 23 is above the gap 27. The paper can be fed until it reaches the vicinity of the press roller 25a, and preliminary paper feeding that is sufficiently close to the preceding original can be realized.

Further, according to this embodiment, the preliminary feeding of the subsequent document is started immediately after the preceding document is conveyed from the first conveyance path 22 to the second conveyance path 29 after being reversed. This early start allows the subsequent document to be conveyed sufficiently close to the preceding document, making it possible to reliably complete the preliminary feeding before the end of the reading exposure of the preceding document at the reading position 5a.

FIG. 5 is a timing chart for explaining the feeding operation in this embodiment, and FIG. 6 is a diagram for explaining the intermittent feeding operation of the document holder.

An example of the document feeding operation in this embodiment will be described below with reference to FIGS. 5 and 6. In addition, in Figure 6,
It is assumed that there are four double-sided originals to be copied, and the suffixes 1 to 4 attached to the reference numbers correspond to the feeding order from the mounting member 6.

Double-sided originals D1 to D4 to be copied are placed on the placing member 6 with the page order aligned, and as shown in FIG. 6(1), when the print switch PSW is operated at time t1, 5(1)), the copying operation is started and the feeding of the document is started. As shown in FIG. 5(2) to FIG. 5(4), driving of the motors M1 to M3 is started in response to the operation of the print switch PSW. The motor M1 is driven intermittently to make the paper feeding means 10 function, and feeds the lowest document D1 on the placement member 6 in the stacking direction. Also, motor M
2. M3 continues to be driven until the copying operation is stopped, and the functions of the conveyance port roller 30, belt 26, and conveyance rollers 20, 21 are switched by connection/disconnection control of clutches CLTI, C'LT2, and CLT3.

At time t2, the first conveyance detector S1 is switched on, and the downstream end of the fed document D1 in the feeding direction 7 begins to be detected. With this switching of the first conveyance detector S1, the clutch CLT3 is connected to drive the conveyance rollers 20, 21 in forward rotation, and the function is to rotate the document D1 in a clockwise direction with respect to the first conveyance path 22. let

By demagnetizing the solenoid 5OLI, the direction changing air 28 is set at the position shown by the solid line in FIG. 1, and the passage from the conveyance path 40 to the first conveyance path 22 is opened. Therefore, the document D1 is conveyed to the first conveyance path 22, and at time t3, the second conveyance detector S2 is turned on, and the downstream end of the document D1 in the sheet feeding direction 7 begins to be detected. FIG. 6(2) shows the state immediately after time t3 when the document D1 is transported to the first transport path 22. In FIG.

As shown in FIG. 6(2), at time t14 when the upstream end of the document D1 in the conveyance direction passes through the first conveyance detector S1, the first
The transport detector S1 is switched to the off state. This time t14
Then, the motor M1 is driven to start conveying the document D2, and the motor M1 is stopped at time t15 when the downstream end of the document D2 in the conveyance direction is detected by the first II feed detector S1.

That is, the motor M1 is driven only for the period T2. As a result, the document D2 is stopped near the direction changing wind 28.

Furthermore, at time t4, the second conveyance detector S2 is also switched to the off state. That is, the upstream end of the document D1 in the paper feeding direction 7 passes through the second conveyance detector S2.

At this time t4, solenoid SQL 1 is energized. Therefore, the direction changing air 28 is switched to the position shown by the dotted line in FIG. 1, and the path from the first conveyance path 22 to the second conveyance path 29 is opened.

Furthermore, at time t4, clutches CLTI, CLT2
The rotational driving force of the motor M3 is transmitted to drive the conveyance roller 30 and the belt 26.

Immediately after time t4, the clutch CLT3 is connected to reversely rotate the transport rollers 20 and 21, thereby reversing the feeding direction of the document D1. The document D1 whose feeding direction has been reversed is transported from the first transport path 22 to the second transport path 29.

Due to the above-mentioned reversal of the feeding direction, the second conveyance detector S2
is switched to the on state at the downstream end of the feeding direction 23 after reversal, and is switched to the off state at time t6 as the conveyance progresses.

Also, at the time t6, the solenoid 5QL1 is demagnetized.

In this embodiment, after the downstream end of the feeding direction 23 of the document D1 after the feeding direction has been reversed on the first conveying path 22 passes through the direction changing wind 28, at a predetermined period of time *(time t8), the clutch CLTI.

CL and T2 are cut, the document D1 is stopped while being held between the transport rollers 30, and the subsequent document D2 is cut as shown in FIG. 6 (3).
), the paper is preliminarily fed to start conveyance to the first conveyance path 22. Therefore, the motor M1 that starts feeding the document D2 starts driving at time t7. In order to convey this subsequent document D2 to the first conveyance path 22, a period T3 (T3=T1-
The conveyance rollers 20 and 21 are driven to rotate normally again over T2>, and the conveyance of the document D2 to the first conveyance path 22 is started.

Along with this, the second conveyance detector S2 is switched to the on state and begins to detect the downstream end of the document D2 in the paper feeding direction 7.

The first conveyance detector S
1 is switched to the off state, and at the same time, the motor M1 is driven for a period T2 in order to convey the document D3. Subsequently, at time t9, the second conveyance detector S2 is also switched to the off state. That is, the upstream end of the document D2 in the paper feeding direction 7 passes through the second conveyance detector S2. At this time t9, clutch C
LT3 is disconnected, the feeding of the document D2 is temporarily stopped, and the solenoid 5OLI is energized to open the path from the first conveyance path 22 to the second conveyance path 29 in the same manner as described above. Then, immediately after time t9, the clutch CLT
3 are connected to drive the conveying rollers 20 and 21 in reverse rotation, thereby reversing the feeding direction of the document D2. Due to this reversal of the feeding direction of the document D2, the second conveyance detector S2 is again switched to the on state at the downstream end of the feeding direction 23 after the reversal (
time t10).

At time t11 after a predetermined period has elapsed from time tlo, that is, the feeding direction of the first document D1 is stopped, 2
At time t11 when the distance between the upstream end of document D2 and the downstream end of document D2 in the feeding direction 23 becomes a predetermined length (see FIG.
), the clutches CLTI and CLT2 are connected, the rotational driving force of the motor M3 is transmitted, the conveyance roller 30 and the belt 26 are rotationally driven, and the document D1 is conveyed to the reading position 5a. At time t12 after a predetermined number of pulses have been measured by a rotary encoder or the like from time tll, clutch CLTI.

By blocking CLT2, the reading position 1 of the document D1 is
5 Transfer to a is completed.

Here, the transport speed of the original DI and the transport speed of the original D2 are selected to be equal, and the interval between the upstream end of the feeding direction 23 of the original Di and the downstream end of the feeding direction 23 of the original D2 is always kept at a constant interval. It is maintained. This interval is selected so that when the original D1 is transported to the reading position 5a, the upstream end of the original D2 in the feeding direction 23 is held between the transport rollers 30 in the same way as the original D1. It will be done.

FIG. 6(5) shows the state at the time when the document D1 has been completely conveyed to the reading position 5a, and the subsequent document D1 is
2 is waiting in a state where a part of the downstream side in the feeding direction 23 is sandwiched between the transparent plate 5 and the belt 26 due to the above-mentioned preliminary feeding, and the succeeding document D3 is further rotated in the feeding direction by the reversing means 18. A reversal operation is being performed.

Simultaneously with the completion of conveyance of the original D1 to the reading position 5a, optical scanning of the optical system 31 in the direction of arrow 44 starts (see FIG. 1).While the reading exposure operation for the original D1 is being performed, The subsequent reversing operation of the original document D3 is performed. FIG. 6(6) shows the state immediately before time t13, in which the reading exposure operation of the original D1 is completed, the reversal operation of the feeding direction of the original D3 is also completed, and the direction change of the original D4 is completed. Conveyance to the vicinity of the claw 28 has also been completed.

At time t13, clutches CLTI and CLT2 are connected to transport the document D1 to the transport path 36, and
The document D2 is conveyed to the reading position 5a, and the document D3 is conveyed at a constant interval with respect to the upstream end of the document D2 in the feeding direction 23. After that, as shown in FIG. 6 (7), the original D
1 is transported along a transport path 36 by transport rollers 34 and 35 and returned onto the mounting member 6. Original D2 is optical system 31
optical scanning is performed. Original D3 is in feeding direction 23
It is stopped with the upstream end being pinched by the conveyance rollers 30. During the reading exposure operation of the original D2, an operation of reversing the feeding direction of the original D4 is performed.

These operations are executed at any time between the continuously fed documents D1 to D4.

Therefore, according to this embodiment, it is possible to individually control the conveyance force of each conveyance path so that it functions effectively, and to feed a subsequent document sufficiently close to the document fed in advance. Therefore, while the preceding original is being read and exposed, the preliminary feeding of the subsequent original can be reliably completed in a state where the original is brought sufficiently close to the preceding original. As a result, the transport distance, that is, the transport time, required to further transport the subsequent document to the reading position is significantly shortened, and as a result,
The time required to transport multiple sheets of documents to the reading position can be significantly reduced. In other words, copying time can be significantly reduced.

Although this embodiment is described in connection with the configuration of a transfer type electrostatic copying machine, other configurations may be used, such as recording on photosensitive recording paper.

Effects of the Invention As described above, according to the present invention, over a plurality of sheet-like originals that are continuously fed by simple control, the following sheet-like original can be conveyed sufficiently close to the preceding sheet-like original. can do. That is, sufficient preliminary feeding of the subsequent sheet-like original can be completed before the reading and exposure of the preceding sheet-like original is completed.

Therefore, it is possible to significantly reduce the time required to transport the subsequent sheet-like original onto the original reading surface, and furthermore, the time required to transport the sheet-like original onto the original reading surface between multiple sheets of original. Copying time can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a simplified configuration of a document feeding device 1 which is an embodiment of the present invention, and FIG. 2 is a simplified diagram of a transfer type electrostatic copying machine 2 equipped with the document feeding device 1. FIG. 3 is a block diagram showing the electrical configuration of the document feeding device 1 and the copying machine 2, and FIG. 4 shows the conveyance state of the document in the document feeding device 1 in each copy mode. 5 is a timing chart for explaining the document feeding operation in this embodiment, FIG. 6 is a diagram for explaining the intermittent document feeding operation, and FIG. 7 is a timing chart for explaining the document feeding operation in this embodiment. 1 is a cross-sectional view showing a simplified configuration of a conventional document feeding device 201. FIG. DESCRIPTION OF SYMBOLS 1... Original feeding device, 2... Copying machine, 5... Transparent plate, 6... Placement member, 18... Reversing means, 22...
1st conveyance path, 23...feeding direction, 26...belt,
27... Gap, 28... Direction change type, 29... Second transport path, 31-- Optical system, D- Original, CLTI, C
LT2 CLT3... Clutch, Sl... 1st conveyance detector, s2 2nd conveyance detector, S3 ・3rd conveyance detector, 5OLl, 5QL2-/L, /id, Ml~M3-Motor agent Patent attorney Saikyo Keibu Part 1

Claims (1)

[Scope of Claims] A plurality of sheet-like originals fed from a mounting member are transported to one of the branched transport paths, the feeding direction is reversed, and the originals are optically transported through the other branched transport path. In the method of feeding sheet-like originals in which the sheet-like originals are continuously and sequentially transported onto the original reading surface facing the reading means, the upstream end of the preceding first sheet-like original in the feeding direction after being reversed passes through a branching position of the transporting path. At this point, the conveyance of the first sheet-like original is stopped, the feeding direction of the following second sheet-like original is reversed, and the following third sheet-like original is further conveyed to the vicinity of the branching position, and the second sheet is When the distance between the downstream end of the reversed feeding direction of the original sheet and the upstream end of the stopped first sheet original in the feeding direction reaches a predetermined length, the first and second sheet originals are moved at a constant speed. A method for feeding a sheet-like original, characterized by feeding the original in sheet form.