JP2002111956A - Double-sided manuscript reading device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-sided manuscript reading device for reducing time required for reading both sides of a manuscript and for putting the pages of a discharged manuscript in order. SOLUTION: The double-sided manuscript reading device comprises a first transport path (a first manuscript transport path R1) for feeding the manuscript to a reading section and for reading a first side for guiding to a first discharge means (an extra roller 30 and a first press roller 31), a second transport path (manuscript transport paths R1, R2, and R3) for inverting the sides of the manuscript by the first discharge means and for feeding the manuscript to the reading section again and then for guiding the second side to a second discharge means (the extra roller 30 and a second press roller 32), and an inverted path (a fourth manuscript transport path R4) for connecting the first and second transport paths. Also, control is made so that the first surface of a next manuscript starts to be read during the discharge operation of a preceding manuscript. Then, the first and second discharge means are composed of three rollers 30, 31, and 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique of a document reading apparatus capable of automatically feeding documents sequentially and reading both sides of the document.

[0002]

2. Description of the Related Art In a conventional manuscript reading apparatus, when reading both sides of a manuscript, the manuscript is first fed to a reading unit to read the surface, and after being conveyed to a discharge port on a discharge tray by a discharge roller, the document is read. The rotation direction of the discharge roller nipping the rear end of the document is reversed, the document is reversed and fed back to the reading unit while being reversed through the document return path, and then the back side is read and discharged to the discharge tray. Was. Further, as an improvement of the above technology, the original conveyed to the discharge port after reading both sides is switched back again, and is again conveyed to the reading unit through the original return path, at which time the reading unit performs reading. A technique has been devised in which the document is passed through as it is, discharged with the front side of the document facing down, and sequentially stacked while rearranging the pages stacked in the paper feed port in order.

[0003]

However, in the above prior art, in order to rearrange the original pages after reading both sides of the document, the document is fed back to the document return path after being switched back on the paper discharge tray and fed back to the document return path. The paper was discharged onto the paper output tray with the front and back turned upside down and sequentially stacked.
As a result, the document passes through the reading unit three times,
In the first pass, the original is passed through the original reading section even though the original is not read, so the next original cannot be taken in until the discharge of the preceding original is completed. It was an evil of shortening. Normally, the return path is shorter than the document length, and in the case of the switchback-reversed document, the leading side of the preceding document reaches the discharge port via the return path, while the terminal side thereof is still repeated at the discharge port. Since the leading end and the trailing end are in the opposite traveling directions, the discharge roller is separated and the leading end and the trailing end are used by utilizing the conveying force of the other rollers. I was passing each other. In order to separate the discharge roller in this way, an expensive mechanism such as an actuator is required, and thus the cost is high.

According to the present invention, a duplex document reading apparatus is improved to solve at least one of the above-mentioned problems, and the time required for reading both sides of a document is reduced, or a mechanism for separating a discharge roller is eliminated to reduce costs. The task is to reduce the emissions.

[Means for Solving the Problems]

[0005] The present invention has been made in order to solve the above problems.
The following means are used. That is, in a document reading apparatus for reading both front and back sides of a document, a first document is fed from a paper feed tray to a reading section, and the first face is read and guided to a first discharge unit. The original is switched back by the transport path and the first discharge unit, and is again fed to the reading unit, where the second side of the original is read and the second side is read.
, And a reverse path that connects the first and second transport paths, reverses the front and back of the document, and guides the document to a paper discharge tray.

According to a second aspect of the present invention, in the double-sided document reading apparatus, control is performed such that reading of the first side of the next document is started during the discharging operation of the preceding document.

According to a third aspect, the first discharging means and the second discharging means are constituted by three rollers.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view of a facsimile adopting a two-sided original reading apparatus, FIG. 2 is a side sectional view of the same, FIG. 3 is a side sectional view of an ADF of the two-sided original reading apparatus, and FIG. FIG. 5 is a block diagram showing a control configuration of the two-sided document reading device, and FIG. 6 is an AD showing a document flow in a first process of the two-sided document reading device.
F is a side sectional view of the ADF showing the flow of the original in the second process, FIG. 8 is a side sectional view of the ADF also showing the flow of the original in the third process, and FIG. FIG. 10 is a flow chart showing the first stage of the control configuration of the double-sided document reading apparatus, and FIG.
Is a flowchart showing the second stage, FIG. 12 is a flowchart showing the third stage, FIG. 13 is a flowchart showing the fourth stage, FIG. 14 is a flowchart showing the fifth stage, and FIG. It is a flowchart.

A double-sided document reading apparatus according to the present invention will be described first with reference to a facsimile apparatus as an example. The facsimile apparatus shown in FIGS.
The reading unit 1 is arranged above the image forming apparatus. Recorder 2
A recording device 3 and a paper feed cassette 4 are respectively provided in the upper and lower sides, and the paper deposited in the paper feed cassette 4 is fed to the recording device 3, and after recording, the paper is discharged to a recording paper discharge tray 5. It is configured to discharge.

The reading section 1 has a hinge 10b extending from the bottom surface of a reading case 10 which is a part of the reading section 1, and is pivotally supported on a hinge pin 1a provided in the recording section 2. With respect to the recording section 2, the recording section 2 can be turned up and down about the hinge pin 1a as a fulcrum.

In the reading section 1, a reading device 6 is housed in a reading case 10. On the upper surface of the reading case 10, a transparent stationary document placing bed 11 is provided.
When a document is placed on the stationary document placing bed 11, the reading device 6 moves from a solid line position to a virtual line position in FIG. 2 to perform scanning.

Above the reading case 10, a document holding cover 7 which can be opened and closed about one side thereof is arranged, and a document placed on the stationary document loading bed 11 is held by the document holding cover 7. Pressing from above.

An ADF 8 is attached to one end of the document holding cover 7.
Is attached. The appearance of ADF8 is as shown in FIG.
Side frames 7a and 7b are provided in parallel in a direction orthogonal to the scanning direction of the reading device 6, and an openable and closable ADF cover is provided between the side frames 7a and 7b so as to cover the entire document transport section of the ADF 8. 14 are arranged so as to be sandwiched therebetween. A of each side frame 7a, 7b
On the inner opening surface along the end of the DF cover 14, side plates made of sheet metal (not shown) are fixed in an upright manner. For example, among the feed rollers described below, for example, each shaft end of a roller shaft of a drive roller is provided. Is supported. Document holding cover 7
And one or both of the side frames 7a and 7b cover the drive source of the drive roller and its transmission system, and the inner surface thereof is covered by the side plate.

The document holding cover 7 and the side frames 7a and 7b form an apparatus main body of the ADF 8, and a document conveying section which is sandwiched between the left and right sides of the apparatus main body and covered by the ADF cover 14 is provided. Make up the whole.

A document supply tray 9 is provided above the document holding cover 7 so as to be continuous with the paper feeding port 8a of the ADF 8, and the document feeding tray 9 of the ADF 8 A document discharge tray 7c is integrally formed so as to be continuous with a paper discharge port 8c disposed immediately below the port 8a. The ADF 8 has a paper feed port 8a to a paper discharge port 8c.
A document transport path is configured up to this point.

Sheet documents stacked on the document supply tray 9 are picked up one by one and inserted into the paper feed port 8a. The document fed by the ADF 8 and passing over the platen glass 12 is read by the reading device 6 at an initial position indicated by a solid line in FIG. The read document is discharged from the paper discharge port 8c onto the document discharge tray 7c.

As described above, the reading unit 1 is used as a flat bed type scanner that scans the reading device 6 to read a still original, and also reads the original while feeding the original to the ADF 8 with the reading device 6 fixed in position. It is configured to be able to be used as a sheet feed type scanner for performing the operation.

A key panel 13 is attached to one side of the reading case 10. By pressing various operation keys on the key panel 13, the contents of the document are read, the destination for facsimile transmission of the read contents is set, and the received contents and the read contents are recorded by the recording device 3. And various operations are performed.

Next, A of the automatic sheet conveying apparatus according to the present invention will be described.
The internal structure of DF8 will be described. In this description, in the side view shown in FIG. 3, the document transport direction is the front-rear direction (in the document transport path, the paper feed port 8a / discharge port 8c side is forward, and the curved portion (transport direction folded portion) side is backward. And.)
The vertical direction in the horizontal direction is defined as the horizontal direction, and the vertical and vertical positions of each structure are described.

First, the configuration of the document conveying path according to the present invention will be described. First, as shown in FIG.
A first document transport path R1 having a shape in which a letter “?” Is laid down in a side view is formed from to the paper discharge port 8c. The first
The document transport path R1 has an arcuate path R1a curved in a “C” shape from the paper supply port 8a, a horizontal path R1c extending horizontally to the paper discharge port 8c, the arcuate path R1a and the horizontal path R1c.
A branch point Q is provided at a rear end position of the horizontal path R1c, and a second document transport path R2 extends rearward from the branch point Q to the first path. The document communication path R1 communicates with the curved portion. Here, this communication point is referred to as a junction P.

A branch point S is provided at a point in the first document transport path R1 where the path changes from the arcuate path R1a to the inclined path R1b, and a sheet document transport direction is provided below the paper discharge port 8c. A temporary outlet 8b for reverse rotation is provided, and a third outlet from the branch point S toward the temporary outlet 8b is provided.
The document transport path R3 extends. A branch point T is provided at an intermediate position between the branch point S and the temporary discharge port 8b in the third document transport path R3. From the branch point T to a first document transport path R1 running back and forth above the branch point T,
A fourth document transport path R4 having a “U” -shape is formed. Here, the fourth document transport path R4 and the first
A point of communication with the document transport path R1 is a junction R. The document transport path is thus formed, wherein the first transport path according to claim 1 is the first document transport path R1, and the second transport path is the same as the horizontal path R1c of the first document transport path R1. Convergence point P of the second document transport path R2 and the first document transport path R1
And a third document conveying path R3 from the first path to the branch point S.
The reverse path connecting the transport path and the second transport path is a fourth document transport path R4.

Next, as for the arrangement of the rollers for feeding the sheet original, an extra roller 30 which can rotate in the normal and reverse directions is disposed between the temporary discharge port 8b and the discharge port 8c. A first press roller 31 and a second press roller 32 are disposed so as to be in sliding contact with each other on the transport paths R1 and R3. Here, the nip between the extra roller 30 and the first press roller 31 in the first document transport path R1 is E, and the nip between the extra roller 30 and the second press roller 32 in the third document transport path R3 is F. .

A nip portion A between the separate roller 22 and the retard roller 23 is provided near the paper feed port 8a, and the arms 20 can swing forward from both ends of the separate roller 22. The arm 20
A pickup roller 21 is pivotally supported at a front end of the pickup roller 20. Then, along the first document conveyance path R1 from the paper feed port 8a to the paper discharge port 8c, the nip portion A between the separate roller 22 and the retard roller 23, the registration roller 2
No. 4 and resist follow roller 25, nip B, first
Nip portion C between feed roller 26 and first slave roller 27, second feed roller 28 and second slave roller 2
9 and a nip portion E between the extra roller 30 and the first press roller 31.

Thus, the pickup roller 21,
The sheet documents stacked on the document supply tray 9 are separated one by one by a separate roller 22, a retard roller 23, and the like, and are fed from the paper feed port 8a to the first document transport path R1.

Of the above-mentioned rollers, the registration roller 2
4, the first feed roller 26, the second feed roller 2
8, and each roller shaft 24a · 2 of the extra roller 30
6a, 28a and 30a have both ends of the shaft
The rollers 22, 24, 26, 28, and 30 are supported by the respective side plates of the DF8 apparatus main body and fixed in position, and the rollers 22, 24, 26, 28, and 30 are provided with a driving source and It is designed to be driven by a transmission mechanism. That is, as shown in FIG.
23, 24, 26, 28 and 30 are drive rollers, each of which is in contact with each of the rollers 25, 27, 29.3
Reference numerals 1 and 32 denote driven rollers that follow the driving rollers.

Then, as shown in FIG. 3, the original document transport paths R1 and R3 are switched between the first original transport path R1 and the third original transport path R3 immediately before the branch point S. A first guide member 37 is provided, and the branch point Q
The first original transport path R1 and the second original transport path R immediately after
2, a second guide member 38 for switching between the document transport paths R1 and R2 is provided.
The first document transport path R1 and the fourth document transport path R immediately after
4, a third guide member 39 for switching between the document transport paths R1 and R4 is provided.

The first guide member 37 includes a solenoid 4
The path is electrically switched using an actuator such as an actuator 7. It is controlled so that the sheet document is fed to the first document transport path R1 after reading the first surface (front side) of the document, and to the second document transport path R2 after reading the second surface (back side) of the document. . On the other hand, the guide member 38.3
A flexible member such as a film is used for 9 and a path is opened in the sheet document conveyance direction. After the sheet document passes, the path returns to its original position due to its own weight and its elasticity, and closes the path. It is configured as follows.

More specifically, the second guide member 38 is normally free to pass from the branch point R to the junction P, and is urged to block the path from the branch point S to the branch point R. Have been. That is, in the conveyance from the paper discharge port 8c to the branch point Q, the merging point R along the second guide member 38
In the conveyance from the branch point S to the branch point Q, the leading end of the sheet document is moved to the second guide member 3.
When the end of the sheet document passes through the position of the branch point Q, the second guide member 38 returns to its original position by its own weight and its elasticity.

The third guide member 39 has substantially the same structure, and is normally free to pass from the nip F to the junction R, and closes the path from the branch S to the nip F. Has been energized. That is, the temporary outlet 8
In the conveyance from b to the branch point T, the sheet is guided along the third guide member 39 in the direction of the junction R. On the other hand, in the conveyance from the branch point S to the branch point T, the leading edge of the sheet document is Is pushed up by the third guide member 39 to be conveyed in the direction of the temporary discharge port 8b, and when the end of the sheet document passes through the position of the branch point T, the third guide member 39 loses its original weight due to its own weight and its elasticity. Return to position. As described above, the second guide member 38 and the third guide member 39 are not electrically switched, are inexpensive members, and have a simple configuration.

Next, each sensor related to the conveyance of the sheet document will be described. First, a document set sensor (hereinafter referred to as "D") is provided near the paper feed port 8a of the first document transport path R1.
S sensor ") 43 is provided. When the sheet document is set deep in the paper feed port 8a, the sheet document is detected by the DS sensor 43, whereby the start button 19 and the drive source 4
1 is connected, and the drive source 41 can be driven. Conversely, in a state where no original is set, even if the start button 19 is pressed while the circuit is cut off, The drive source 41 does not start, and thus the idle feeding of the document is prevented. Then, along the first document transport path R1, a junction P with the second document transport path R2 is established.
A registration sensor 44 is provided in the vicinity, and a reversing sensor 45 is provided in the vicinity of a branch point S from the third document transport path R3. Each of the sensors 43, 44, and 45 has a light emitting element disposed on one side of the transport path,
It is constituted by an optical sensor having a light receiving element arranged on the other side, a limit switch, or the like, and detects when the passage of a sheet document passing through the sensor arrangement position starts or when the passage of the sheet document is completed, and the like. Outputs a control signal (detection signal).

Further, in addition to the sensors 43, 44, and 45, the above-described controller 40 shown in FIG. 5 is also connected to a control member described below, and controls a sheet original transport pattern. Reference numeral 37 denotes the above-described first guide member that regulates the direction in which the document is transported.
Receiving the control signal (switching signal) from the printer, the document transport path is switched. That is, in the normal state, the first guide member 37 closes the third document transport path R3 and opens the first document transport path R1, and receives a control signal (switch signal) from the controller 40, An electric current flows through the solenoid 47, and an actuator acts to rotate the first guide member 37 slightly upward to close the first document transport path R1 and open the third document transport path R3.

The pickup roller 21 is configured to swing up and down using an actuator such as a solenoid 46, and receives a control signal (drive signal) from the controller 40 so that a current flows through the solenoid 46. The actuator acts to rotate the pickup roller 21 downward to hold down the sheet document. Further, the driving source 41 of each roller 22, 23, 24, 26, 28, 30 is:
Upon receiving a control signal (drive signal) from the controller 40, each of the rollers 22, 23, 24, 26, 28
・ Drive / stop 30. The drive source 41 uses a stepping motor or the like in which a pulse is sequentially applied to the multi-phase winding of the stator and the rotor rotates by a fixed angle for each pulse. The controller 40 performs step control. hand,
The number of rotation steps of the drive source 41 is measured.

The rollers 22, 23, 24, 26, 28
The rotation direction is interlocked with the forward / reverse rotation of the drive source 41. However, the extra roller 30 is controlled via a forward / reverse rotation switching mechanism 48 shown in FIG. Then, a control signal (switching signal) is output from the controller 40 to the electromagnetic clutch 49 of the forward / reverse rotation switching mechanism 48, and the rotation direction of the extra roller 30 is switched. The forward / reverse rotation switching mechanism 48 is provided between the drive source 41 and the extra roller 30, and is provided between the drive shaft to which the power from the drive source 41 is transmitted and the output shaft for outputting to the extra roller 30. Is provided with a same-direction transmission mechanism for transmitting rotation in the same direction as the drive shaft, and the other is provided with a reverse rotation transmission mechanism for transmitting the rotation in the reverse direction, and is spline-fitted to the drive shaft or the output shaft. The electromagnetic clutch 49 is slid and disengaged, the connection with one transmission mechanism is released, and the other transmission mechanism is connected, and only one rotation is taken out to the output shaft via the electromagnetic clutch 49. In this way, in conjunction with the switching operation of the first guide member 37, a control signal (switching signal) is output from the controller 40 to the electromagnetic clutch 49 of the forward / reverse rotation switching mechanism 48, and the rotation direction of the extra roller 30 is switched. The configuration of the forward / reverse rotation switching mechanism 48 is not limited to the above description.
The switching device may be shared with the forward / reverse rotation switching mechanism 48, that is, the first guide member 37 and the forward / reverse rotation switching mechanism 48 may be operated by a single switching device. In this case, the actuator (electromagnetic clutch 49) of the forward / reverse rotation switching mechanism 48 via the solenoid 47 and the first
The actuator of the guide member 37 is operated together.
In this configuration, the number of parts can be reduced, the cost can be reduced, and the rotation direction of the extra roller 30 is simultaneously switched in conjunction with the switching operation of the first guide member 37, so that the sheet document can be more reliably printed. It can be transported in a desired direction.

As shown in FIG. 4, an electromagnetic clutch 51 is provided between the drive source 41 and the separate roller 22, and receives a control signal (stop command signal) from the controller 40 to The electromagnetic clutch 51 is disconnected, and the separate roller 22 is stopped. Of course, other power connection / disconnection mechanisms may be used in addition to the electromagnetic clutch 51. A one-way clutch 50 is interposed between the drive source 41 and the registration roller 24, and the power is transmitted only when the drive source 41 is rotating in the reverse direction. Also, on a key panel 13 shown in FIG. 1, a function key 18 for setting a reading mode such as a conversion of one-sided / two-sided reading, a start button 19 for starting a sheet document loading operation, and a plurality of sheet documents A stop button 16 and the like for stopping the reading operation halfway, such as when reading continuously, are provided. The function key 18, the start button 19, the stop button 1
When an operation such as 6 is performed, a control signal is output to the controller 40.

Here, the flow of double-sided reading of a sheet document according to the present invention will be schematically described. First, as shown in FIG. 6, the sheet document set on the document feed tray 9 with its front side facing upward is fed in a first step in a sheet feed port 8a → nip section A → converging point P → nip section B → nip section. The document is conveyed to the portion C → the nip portion D → the branch point S → the branch point Q → the junction R → the nip portion E → the paper discharge port 8c to read the first surface of the document, that is, the front surface. Next, as shown in FIG.
In the process, the discharge port 8c → the nip E → the junction R → the branch point Q
→ Junction point P → Nip section B → Nip section C → Nip section D → Branch point S → Branch point T → Nip section F → Conveyance to temporary discharge port 8b to read the back side as the second side of the document . Then, as shown in FIG. 8, in the third step, the temporary discharge port 8b → the nip portion F → the branch point T → the junction R → the nip portion E.
The document is conveyed to the paper discharge port 8c, the document is turned upside down, and the document is discharged to the discharge tray 7c with the surface of the document facing down. Hereinafter, duplex reading of a sheet document according to the present invention will be described with reference to a time chart shown in FIG. 9 and flowcharts shown in FIGS. 10 to 15. Further, it is appropriate to appropriately refer to the diagrams showing the sheet document conveyance patterns shown in FIGS. 6 to 8.

As shown in FIG. 10, first, the user sets a sheet document on the document feed tray 9 with the front side of the sheet face up, and inserts it deep into the sheet feed port 8a (step S1).
The leading edge of the sheet document is detected by the DS sensor 43 (step S2), thereby preparing to take in the document.

Next, the user operates the function key 18 of the key panel 13 to select the original reading surface in the both-side reading mode (step S3), and presses the start button 19 provided on the key panel 13 (step S3). Step S
4), the pickup roller 21 from the controller 40,
A control signal is output to the drive source 41 and the electromagnetic clutch 51 of the separate roller 22, and the pickup roller 21
A positive pulse is applied to the solenoid 46, and the solenoid 46 is momentarily excited. As a result, the pickup roller 21 rotates downward (step S5) and presses down the sheet document, and its position and orientation is maintained until the loading of all sheet documents is completed. At the same time, the drive source 41 starts rotating in the normal rotation direction (step S6).
When the electromagnetic clutch 51 of the separate roller 22 is connected (step S7), each of the drive rollers 22, 26, and 28 starts rotating in the normal rotation direction (clockwise in FIG. 6).

The extra roller 30 starts to rotate in the reverse direction (counterclockwise in FIG. 6) via the reverse rotation transmission mechanism of the forward / reverse rotation switching mechanism 48.
In No. 4, the rotational power is cut off by the one-way clutch 50, and is stopped as it is. In this way, only the uppermost sheet document (first sheet document) is separated by the pickup roller 21, the separate roller 22, the retard roller 23, and the like, and is slowly taken in from the paper feed port 8a (step S8).

When the leading edge of the first sheet document is detected by the registration sensor 44 (step S9),
After the leading end of the sheet document is conveyed from the position of the registration sensor 44 to the position of the nip portion B between the registration roller 24 and the registration follow roller 25 by the step control of the driving source 41, the rotation direction of the driving source 41 is reversed ( Step S10). At this time, the leading end of the sheet document is in a state of being abutted against the nip portion B between the registration roller 24 and the registration follow roller 25, and when the drive source 41 starts rotating in the reverse direction, the one-way clutch 50 is connected. Then, the registration roller 24 starts rotating. The rotation direction of the other rollers 26, 28, 30 is also reversed, that is, the feed rollers 26, 28 rotate in the reverse direction (counterclockwise in FIG. 6), and the reverse rotation transmission mechanism of the forward / reverse rotation switching mechanism 48 operates. The extra roller 30 starts rotating in the normal rotation direction (clockwise in FIG. 6). At this time, a control signal is output to the electromagnetic clutch 51 of the separate roller 22, the electromagnetic clutch 51 is disengaged, and the rotation of the separate roller 22 is stopped (step S11). is there.

In this manner, the sheet document is conveyed while the skew of the sheet document is adjusted by the registration rollers 24 and the registration follow rollers 25, and the controller 40 controls the driving source 41 so that the leading end of the sheet document is moved from the position of the registration sensor 44 to the platen. The number of rotation steps (first rotation angle) of the drive source 41 corresponding to the distance conveyed to the rear end position of the glass 12 is measured, and after reaching the first rotation angle as shown in FIG. S12) A control signal is output from the controller 40 to the reading device 6, and first,
The reading of the front surface of the first sheet document is started (step S13).

In this manner, the first sheet original is composed of the registration roller 24 and the registration follow roller 25, the first feed roller 26 and the first slave roller 27, and
When the sheet is conveyed by the second feed roller 28 and the second slave roller 29 and the registration sensor 44 detects that the end of the first sheet document has passed (step S14), the detection signal is sent to the controller. The control signal is output from the controller 40 to the reading device 6.

When the registration sensor 44 detects the passage of the end of the first sheet document, the controller 40 moves the end of the sheet document from the position of the registration sensor 44 to the front end position of the platen glass 12. The number of rotation steps (second rotation angle) of the drive source 41 corresponding to the distance to be performed is measured, and after reaching the second rotation angle (step S15), the reading of the front surface of the first sheet document is completed. (Step S16).

Then, the first sheet document is the first sheet document.
The document further advances along the guide member 37 to the downstream side of the first document transport path R1, pushes up the second guide member 38, and is transported in the direction of the paper discharge port 8c. Then, the first sheet document is fed out by the extra roller 30 and the first guide roller 31, and when the leading end passes through the position of the reversing sensor 45 while the leading end is being discharged from the discharge port 8c (step S17). The detection signal is output from the inversion sensor 45 to the controller 40. From this time, the controller 40 determines the number of rotation steps (third rotation angle) of the drive source 41 corresponding to the distance that the end of the sheet document is transported from the position of the reversing sensor 45 to the intermediate position between the branch point Q and the junction R. ) Is measured, and after reaching the third rotation angle (step S18), a control signal is output from the controller 40 to the drive source 41, and the rotation direction of the drive source 41 is reversed (step S19).

Here, the drive source 41 starts to rotate in the normal direction, whereby the one-way clutch 50 is disengaged,
The registration roller 24 stops. Also, other rollers 26
The rotation direction of the rollers 28 and 30 is reversed, that is, the feed rollers 26 and 28 rotate in the normal rotation direction (clockwise in FIG. 6), and the extra rollers 30 via the reverse rotation transmission mechanism of the forward / reverse rotation switching mechanism 48 Reverse direction (counterclockwise in FIG. 6)
Start to rotate.

Here, the first sheet document nipped by the extra roller 30 and the first guide roller 31 is reversed by switchback and conveyed in the opposite direction (rearward). After the end of the first sheet document has passed the branch point Q, the second guide member 38 has returned to its original position by its own weight. The document is fed to the second document transport path R2 along the member 38.

As shown in FIG. 12, when the leading edge of the first sheet document is detected again by the registration sensor 44 (step S20), the leading edge of the sheet document is moved by the step control of the driving source 41. From the position of the registration sensor 44, the registration roller 24 and the registration follow roller 25
Then, the rotation direction of the drive source 41 is reversed (step S21). At this time,
The leading edge of the sheet document is in a state of being abutted against a nip portion B between the registration roller 24 and the registration follow roller 25, and when the drive source 41 starts rotating in the reverse direction, the one-way clutch 50 is connected, and the registration roller is connected. 2
4 begins to spin. Also, the other rollers 26, 28, 30
The rotation direction is also reversed, that is, the feed roller 26
Reference numeral 28 rotates in the reverse direction (counterclockwise in FIG. 7), and the extra roller 30 via the reverse transmission mechanism of the forward / reverse rotation switching mechanism 48 starts rotating in the forward direction (clockwise in FIG. 7).

At this time, a control signal is output from the controller 40 to the first guide member 37,
A current flows through the solenoid 47 of the guide member 37. This excites the solenoid 47 to rotate the first guide member 37 slightly upward (step S22).

In this way, the first original conveying path R1 is closed and the third original conveying path R3 is opened. By switching the first guide member 37, a control signal is outputted to the forward / reverse rotation switching mechanism 48, and the electromagnetic clutch 49 is switched. Then, the power from the drive source 41 is transmitted through the same direction transmission mechanism of the forward / reverse rotation switching mechanism 48, and the extra roller 30 immediately starts rotating in the reverse direction (counterclockwise in FIG. 7) ( Step S23). The first guide member 3 described above
In the case of a configuration in which the switching device for the forward and reverse rotation switching mechanism 48 is shared, the operations of step S22 and step S23 occur at the same time, and the solenoid 47 is excited, so that the first guide member 37 and the forward / reverse rotation are switched. The rotation switching mechanism 48 is switched.

The sheet document is conveyed while the skew of the sheet document is adjusted by the registration roller 24 and the registration follow roller 25, and the controller 40 controls the driving source 41 so that the leading end of the sheet document is moved from the position of the registration sensor 44 to the platen. The number of rotation steps (first rotation angle) of the drive source 41 corresponding to the distance conveyed to the rear end position of the glass 12 is measured, and after reaching the first rotation angle (step S24), the controller 40 A control signal is output to the reading device 6, and reading of the back surface of the first sheet document is started (step S25).

In this manner, the first sheet original is composed of the registration roller 24 and the registration follow roller 25, the first feed roller 26 and the first slave roller 27, and
When the sheet is conveyed by the second feed roller 28 and the second slave roller 29 and the registration sensor 44 detects that the end of the first sheet document has passed (step S26), the detection signal is sent to the controller. The control signal is output from the controller 40 to the reading device 6.

After the registration sensor 44 detects that the end of the first sheet document has passed, the controller 40 conveys the end of the sheet document from the position of the registration sensor 44 to the front end position of the platen glass 12. The number of rotation steps of the drive source 41 corresponding to the distance (second
After the rotation angle is measured and reaches the second rotation angle (step S27), reading of the back surface of the first sheet document is completed (step S28).

Then, the first sheet document is the first sheet document.
The document is fed to the third document transport path R1 along the guide member 37, and then is pushed up by the third guide member 39 to be transported in the direction of the temporary discharge port 8b. As shown in FIG. 13, the first sheet document is fed out by the extra roller 30 and the second guide roller 32, and the leading end thereof is discharged from the temporary discharge port 8b, and the end thereof is positioned at the reversing sensor 45. (Step S29), the detection signal is output from the inversion sensor 45 to the controller 40. From this time, in the controller 40, the number of rotation steps (the fourth rotation angle) of the drive source 41 corresponding to the distance that the end of the sheet document is transported from the position of the reversing sensor 45 to the intermediate position between the branch point T and the nip portion F Is measured, and the fourth
Is reached (step S30), if there is a next sheet document (second sheet document) in the paper feed port 8a by the DS sensor 43 (step S31), the controller 40 A control signal is output to the electromagnetic clutch 41 of the separate roller 22. As a result, the drive source 41 starts to rotate in the normal rotation direction (step S32), and the electromagnetic clutch 51 of the separate roller 22 is connected (step S33).
2.26.28.30 is the forward direction (clockwise in FIG. 6)
Start to rotate. The rotation power of the registration roller 24 is cut off by the one-way clutch 50, and the registration roller 24 stops here.

In this way, the next sheet document is separated by the pickup roller 21, the separate roller 22, the retard roller 23 and the like, and is slowly taken in from the paper feed port 8a (step S34).

When the leading edge of the next sheet document is detected by the registration sensor 44 (step S35), the leading edge of the sheet document is moved from the position of the registration sensor 44 to the registration roller 24 by the step control of the driving source 41. After being conveyed to the nip portion B position with the follow roller 25, as shown in FIG. 14, the rotation direction of the drive source 41 is reversed (step S36). At this time, the leading end of the sheet document is in a state of being abutted against the nip portion B between the registration roller 24 and the registration follow roller 25, and when the drive source 41 starts rotating in the reverse direction, the one-way clutch 50 is connected. Then, the registration roller 24 starts rotating. The rotation direction of the other rollers 26, 28, 30 is also reversed, that is, the feed rollers 26, 28 rotate in the reverse direction (counterclockwise in FIG. 6), and the reverse rotation transmission mechanism of the forward / reverse rotation switching mechanism 48 operates. Extra roller 30 through
Starts rotating in the normal direction (clockwise in FIG. 6).

At this time, the separate roller 22,
Then, a control signal is output to the first guide member 37, the electromagnetic clutch 51 of the separate roller 22 is disengaged, and the rotation of the separate roller 22 is stopped (step S37).
The current flowing through the solenoid 47 of the first guide member 37 is cut off, and the first guide member 37 is returned to the original position (step S38). Here, the first guide member 37 closes the third document transport path R3 and opens the first document transport path R1. By this switching, a control signal is output to the forward / reverse rotation switching mechanism 48, and the electromagnetic clutch 49 is switched. This time, power from the drive source 41 is transmitted via the reverse rotation transmission mechanism of the forward / reverse rotation switching mechanism 48, and the extra roller 30 immediately reverses in the normal rotation direction (clockwise in FIG. 6) and starts rotating ( Step S39).

In this manner, the next sheet document is conveyed while the skew of the sheet document is adjusted by the registration roller 24 and the registration follow roller 25, and the controller 40
Then, the leading edge of the sheet document is moved from the position of the registration sensor 44 to the platen glass 1 by the step control of the driving source 41.
2. The number of rotation steps (first rotation angle) of the drive source 41 corresponding to the distance conveyed to the rear end position is measured, and the first rotation angle is calculated.
Is reached (step S40), a control signal is output from the controller 40 to the reading device 6, and reading of the next sheet original surface is first started (step S41).

In this manner, the next sheet original is formed of the registration roller 24 and the registration follow roller 25, the first feed roller 26 and the first slave roller 27, and the second sheet document.
When the sheet is conveyed by the feed roller 28 and the second slave roller 29 and the registration sensor 44 detects that the end of the next sheet document has passed (step S).
42), the detection signal is output to the controller 40,
A control signal is output from the controller 40 to the reading device 6.

When the registration sensor 44 detects the passage of the end of the next sheet document, the controller 40 conveys the end of the sheet document from the position of the registration sensor 44 to the front end position of the platen glass 12. The number of rotation steps (second rotation angle) of the driving source 41 corresponding to the distance is measured, and after reaching the second rotation angle (step S43), reading of the next sheet document surface is ended (step S44). ). Then, the next sheet document is conveyed by the second feed roller 28 and the second slave roller 29, further proceeds along the first guide member 37 to the downstream side of the first document conveyance path R1, and The guide member 38 is pushed up to be conveyed in the direction of the paper discharge port 8c.

At the same time as the next sheet document is taken in at step S35, the first sheet document nipped by the extra roller 30 and the second guide roller 32 is switched back in the reverse direction, Backward). The third guide member 39 has returned to its original position by its own weight when the end of the first sheet document has passed the branch point T in the direction of the temporary discharge port 8b. Therefore, the first sheet document is guided along the third guide member 39 to the fourth document transport path R4.

Then, the first sheet document is fed out of the discharge port 8c by the extra roller 30 and the first press roller 31, and the document is placed on the discharge tray 7 with the document surface facing down.
c (step S45).

The state at this time will be described in detail. At this time, the next sheet document is also transported along the first document transport path R1 in accordance with the flow of steps S34 to S44. The next original sheet catches up during the paper ejection. Therefore, when the first sheet document is fed out by the extra roller 30 and the first press roller 31, the end of the first sheet document and the leading end of the next sheet document are overlapped, and the first sheet document is discharged. Then, the next sheet document is switched back. By performing such control, when reading both sides of a plurality of sheet documents, the reading time can be shortened, and work efficiency is improved. Thereafter, the next sheet document returns to step S17, and is conveyed in the same manner as the first sheet document, and the reading process is performed.

In this way, the sheet originals are read one after another. However, when the reading of both sides of the last sheet original is completed, the DS sensor 43 is turned off because there is no next sheet original. Is selected, and in this case, the drive source 41
Is output. (As shown in FIG. 9, to be precise, when the last sheet document (here, the second sheet document) has been taken in, the DS sensor 43
Is turned off, and thereafter, a control signal is output from the controller 40 to the pickup roller 21, and a negative pulse is applied to the solenoid 46 of the pickup roller 21. This excites the solenoid 46 momentarily,
The pickup roller 21 has rotated upward and returned to the original position. As shown in FIG. 15, the drive source 41 starts to rotate in the normal rotation direction (step S46), and the last sheet document nipped by the extra roller 30 and the second guide roller 32 is switched back inversion. Then proceed in the opposite direction (backward).

At this time, since the third guide member 39 has returned to the original position by its own weight, the last sheet document is transferred along the third guide member 39 to the fourth document transport path R4.
You will be guided to Then, the last sheet document is fed out of the discharge port 8c by the extra roller 30 and the first press roller 31, and is discharged to the discharge tray 7c (step S47).

In the controller 40, the rotation step of the drive source 41 from when the drive source 41 reverses the rotation direction in step S47 to when the last sheet document is completely discharged through the fourth document transport path R4. The number (fifth rotation angle) is measured, and when the fifth rotation angle is reached (step S48), a control signal is output to the first guide member 37 and the drive source 41.

The control signal cuts off the current flowing through the solenoid 47 of the first guide member 37, closes the third document transport path R3 where the first guide member 37 is located, and opens the first document transport path R1. (Step S49), and the switching is performed by the forward / reverse rotation switching mechanism 4
8, a control signal is output, and the electromagnetic clutch 49 is connected to the reverse rotation transmission mechanism of the forward / reverse rotation switching mechanism 48 (step S50). That is, by this operation, the forward / reverse rotation switching mechanism 48 has returned to the initial state at the start of the document taking-in. Finally, the drive source 41 stops receiving the control signal (step S51). Thus, reading from the first sheet document to the last sheet document is performed,
A series of operations is completed. Note that, in the time chart shown in FIG. 9, the reading of the original is set to two sheets for the sake of space, and the second sheet original corresponds to the last sheet original here.

By configuring the document conveying path in this manner, the platen glass 12 at the reading position of the sheet document can be used.
The upper pass only needs to be performed twice when reading the front and back sides of the document, so that the next sheet document can be immediately taken into the first document transport path R1 during the discharge process after reading both sides of the document, thereby improving the document reading speed. Can be achieved.

Further, the sheet original before being discharged after the double-sided reading is not passed through the reading position.
In this case, the sheet document is fed by the extra roller 30 and the second press roller 32 while being discharged by the extra roller 30 and the first press roller 31. 3
1 or the rollers 30 and 32 can be stably conveyed without being separated, thereby simplifying the control configuration of the apparatus. Further, the sheet documents to be discharged are stacked on the discharge tray 7c in the order of the original pages via the fourth document transport path R4, so that it is not necessary to rearrange the documents and the work efficiency is improved.

[0068]

As described above, the present invention has the following advantages. That is, claim 1
In a document reading apparatus that reads both sides of a document, a first conveyance path that feeds a document from a paper feed tray to a reading unit, reads the first side, and guides the first side to a first discharge unit; The first discharge unit switches the document back and feeds the document to the reading unit again, reads the second surface of the document, and guides the second surface to the second discharge unit. A document path is connected to the conveyance path, and the document is passed through the reading unit twice when reading the first and second sides of the document by forming a reverse path that reverses the front and back of the document and guides the document to the discharge tray. Therefore, the next document can be immediately taken into the reading section in the discharge process after reading both sides of the document, and the document reading speed can be improved. In addition, the original before the two-sided reading is discharged through the reversing path that does not pass through the reading unit. However, the discharge roller serving as a discharging unit for sending the document from the second conveying path to the first conveying path is separated. It is not necessary to do so, and the control configuration can be simplified. Further, since the discharged originals are stacked on the discharge tray in the original page order via the reversing path, the work of re-arranging the originals can be omitted, and the work efficiency can be improved.

According to a second aspect of the present invention, in the double-sided original reading apparatus, the control is performed such that the reading of the first side of the next original is started during the discharging operation of the preceding original, whereby a plurality of originals are read. When reading both sides, the operation time can be shortened, and the reading processing efficiency can be improved.

More specifically, a driving / driven roller constituting a first discharging means of the first conveying path and a second discharging means of the second conveying path are specifically constituted. The driving roller is shared with the driving / driven roller to be driven, and the driven roller is slidably contacted on the upper and lower sides, and thus,
By configuring the first discharging means and the second discharging means with three rollers, it is possible to reduce the number of components and to reduce costs.

[Brief description of the drawings]

FIG. 1 is a perspective view of a facsimile employing a two-sided document reading apparatus.

FIG. 2 is a side sectional view of the same.

FIG. 3 is a side sectional view of an ADF of the duplex document reading apparatus.

FIG. 4 is an explanatory diagram illustrating a configuration of transmitting power to each driving roller related to document conveyance.

FIG. 5 is a block diagram illustrating a control configuration of the duplex document reading apparatus.

FIG. 6 is a side sectional view of the ADF showing a flow of a document in a first process of the duplex document reading apparatus.

FIG. 7 is a side cross-sectional view of the ADF showing a flow of a document in a second process.

FIG. 8 is a side sectional view of the ADF showing a flow of a document in a third process.

FIG. 9 is a time chart of a control configuration of the duplex document reading apparatus.

FIG. 10 is a flowchart showing a first stage of the control configuration of the duplex document reading apparatus.

FIG. 11 is a flowchart showing the second stage.

FIG. 12 is a flowchart showing a third stage.

FIG. 13 is a flowchart showing a fourth stage.

FIG. 14 is a flowchart showing a fifth step.

FIG. 15 is a flowchart showing the final stage.

[Explanation of symbols]

 Reference Signs List 8 ADF 8a Paper feed port 8b Temporary discharge port 8c Discharge port 21 Pickup roller 22 Separate roller 30 Extra roller 31 First press roller 32 Second press roller 40 Controller 41 Drive source R1 First document transport path R2 Second document transport path R3 Third document transport path R4 Fourth document transport path

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/00 106 G03G 15/00 106 3F100 107 107 5C062 H04N 1/04 H04N 1/12 Z 5C072 F term ( Reference) 2H012 CC16 CC17 CC21 CC25 2H028 BA03 BA09 2H076 AA58 BA24 BA35 BA36 BA42 BA65 BA83 BA95 2H108 AA15 BA07 CB01 DA06 3F053 BA03 BA14 BA18 EA04 EB01 EB04 EC02 ED15 LA05 LB02 3F100 AA03 AC12 AB03 AC02 AC13 AD06 5C072 AA01 BA03 BA05 NA07 NA08 WA02

Claims (3)

[Claims] 1. A document reading device for reading both front and back sides of a document, a first conveyance path for feeding a document from a paper feed tray to a reading unit, reading the first side thereof, and guiding the document to a first discharging unit; The original is switched back by the first discharging means and fed back to the reading section, and the second side of the original is read and the second side is read.
And a reverse path for connecting the first and second transport paths to each other, for inverting the front and back of the document, and guiding the document to a discharge tray. Double-sided document reader. 2. The double-sided document reading device according to claim 1, wherein the double-sided document reading device is controlled to start reading the first surface of the next document during the discharging operation of the preceding document. . 3. The double-sided document reading apparatus according to claim 1, wherein said first discharging means and said second discharging means are constituted by three rollers.