JP2001255706A - Automatic document reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic document reader by which the document of irregular size is fed and also is read without causing the lowering of productivity and reliability. SOLUTION: This automatic document reader having a feeding means 1 to feed a document M and a reading means 2 to read the image of the document M fed is provided with an inputting means 3 to input the length L of the document M in a feeding direction before the start of reading and a controlling means 4 to control the reading process of the document M based on size information from the inputting means 3. Also, in the automatic document reader having the feeding means 1 to feed the document M and the reading means 2 to read the image of the document M fed, and is provided with a detecting means 5 to detect the length L of the document M in the feeding direction before the start of the reading and a controlling means 6 to control the reading process of the document M based on the size information from the detecting means 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading apparatus used for reading a document image in a copying machine, a scanner, a facsimile, and the like, and more particularly to an effective document reading apparatus for continuously reading images of a plurality of documents. The present invention relates to an improvement of an automatic document reading device.

[0002]

2. Description of the Related Art Conventionally, as an automatic document reading apparatus used in a copying machine or the like, for example, documents stacked on a document tray or the like are sequentially conveyed to an image reading section and discharged to a discharge tray or the like after image reading is completed. Such is known.
In this type of automatic document reading apparatus, a document jam (jam) may occur during document conveyance, and there is a problem that the document is damaged or damaged due to the jam. Therefore, a document detection sensor is provided in the document transport path to monitor the occurrence of a jam, and when the jam occurs, the transport of the document is stopped.

As a method for detecting such a jam, an elapsed time from when the leading edge of a conveyed document is detected by the document detection sensor is measured, and when the elapsed time exceeds a predetermined time. In addition, a method of determining that a jam has occurred is used. This specified time is
It depends on the size of the document (the length in the transport direction). Therefore, in the related art, a plurality of sensors are provided in a direction that is perpendicular to the document transport direction in the document transport path, and based on the detection results of these sensors, that is, the length in the direction that is perpendicular to the document transport direction, Is applied to a standard size (for example, a JISA series or a B series), and the jam is monitored for a predetermined time previously determined from the length of the original in the conveying direction and the conveying speed of the standard size document.

[0004]

Documents used in ordinary offices include the above-mentioned JISA series and B-type documents.
In addition to the standard sizes such as the series, there are also many non-standard sizes such as slips, computer forms, and manuscripts output on roll paper. Then, when trying to convey such an irregular size document by the automatic document reading apparatus described above, the length in the conveyance direction is determined by the length in the direction orthogonal to the conveyance direction of the irregular size document, that is, However, since the specified time is determined based on the length in the transport direction of a document of a fixed size different from the true length of the document in the transport direction, for example, a document having only a significantly longer length in the transport direction than the fixed size is used. In this case, the specified time is set to be significantly shorter than the time that should be originally set. As a result, there is a problem that the apparatus is erroneously detected as a jam during document conveyance, and the apparatus stops. In addition, in the case of a document in which only the length in the transport direction is significantly shorter than the standard size, the specified time is set to be significantly longer than the originally set time, thereby delaying the detection of a jam when a jam occurs. There is a problem that the original is damaged.

Therefore, in a copying machine equipped with such an automatic document reading device, a large number of non-standard size originals of the same size are copied in spite of the automatic document reading device. However, there is a technical problem that the operator is forced to copy while setting the sheets one by one on the platen glass, which is very troublesome and lowers the productivity.

In order to solve such a technical problem, Japanese Patent Application Laid-Open No. H11-227986 discloses that a sensor is provided on an upstream side and a downstream side of an image reading section in a document conveying path, respectively. There has been proposed a technique in which a criterion for detecting a jam by a sensor on the downstream side is changed based on the detection result (conveyance amount of the document).

However, when such a method is adopted, a document jam on the downstream side of the image reading unit can be detected, but a document jam on the upstream side of the image reading unit cannot be detected. There was a technical problem that the performance was reduced. Note that Japanese Patent No. 2780292 and Japanese Patent Application Laid-Open No. 10-210229 also disclose techniques for reading an irregular-size original, but do not disclose measures for jamming the original.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned technical problems, and has been made in consideration of the above-mentioned problems. A document reading device is provided.

[0009]

That is, according to a first aspect of the present invention, as shown in FIG. 1A, a conveying means 1 for conveying a document M, and a reading device for reading an image of the document M being conveyed. Input means 3 for inputting the length L of the document M in the transport direction before starting reading.
And a control means 4 for controlling a reading process of the document M based on the size information from the input means 3.

In such a technical means, as long as the conveying means 1 can convey the document M, a roll conveying member, a belt conveying member or a combination thereof may be appropriately selected.

The reading means 2 may be of a type capable of reading the image of the document M being conveyed, if it is capable of reading the image of the document M being conveyed by the conveying means 1 in a fixed state (a so-called drift reading method). Alternatively, a document that is temporarily stopped during conveyance and read while moving (so-called lay-in reading method) may be appropriately selected.

Further, the input means 3 outputs the original M
Any length may be used as long as the length L in the transport direction can be input. At the same time, the length in the direction orthogonal to the transport direction of the document M may be input.

Further, the control means 4 comprises the input means 3
The reading process of the original M is controlled based on the size information from. The reading process here includes, for example, driving of the transport unit 1, timing of reading an image by the reading unit 2, And a jam detection timing of the document detection sensor S for detecting a jam provided in the conveyance path of the document M.

FIG. 1B shows a second embodiment of the present invention.
As shown in FIG. 1, in an automatic document reading apparatus provided with a transport unit 1 for transporting the original M and a reading unit 2 for reading an image of the original M to be transported, the length L of the original M in the transport direction before the reading is started. And a control unit 6 for controlling a reading process of the document M based on the size information from the detecting unit 5.

In such technical means, the transport means 1 and the reading means 2 may be appropriately selected from those described in the first embodiment of the present invention.

The detection means 5 may be appropriately selected as long as it can detect the length L of the document M in the transport direction before the reading is started. As a specific mode, for example, a type that detects the size of the original M placed stationary on an original mounting plate such as a so-called platen glass or a copy glass, or the original M And a type that detects the size of a moving document provided in the transport path of the document.

Further, the control means 6 controls the reading process of the original M based on the size information from the detecting means 5. Drive and reading means 2
, And the jam detection timing of the document detection sensor S for detecting a jam provided in the conveyance path of the document M.

In the first and second aspects of the present invention, from the viewpoint of efficiently reading a plurality of non-standard-size originals of the same size, the control means 4 or 6 may include a plurality of non-standard-size originals. Under the condition that the mode of reading the image of the original M of the same size is selected, the second and subsequent originals M based on the size information of the first original M
It is preferable to control the reading process of the data.

Further, in the first and second aspects of the present invention, from the viewpoint of efficiently reading a double-sided image of a double-sided original, the control means 4 or 6 may be used.
Preferably, under the condition that the mode of reading the image of the double-sided document is selected, the reading process of the document M on the back side is preferably controlled based on the size information of the document M on the front side.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the accompanying drawings. First Embodiment FIG. 2 shows a first embodiment of an image forming apparatus (multifunction machine of a copier, a facsimile, a printer, and a scanner) to which the automatic document reading apparatus according to the present invention is applied. In the figure,
The image forming apparatus according to the present embodiment is an apparatus main body 1 in which an image forming unit by a well-known electrophotographic process is built.
And an automatic double-sided document feeder 20 as an automatic document reading device disposed on the upper side of the apparatus main body 10. Here, in addition to the above-described image forming unit, paper trays 11 to 14 containing various sizes of paper are provided in the lower part of the apparatus main body 10, and a multi-bypass tray 15 is provided on a side portion thereof. ing. On the other hand, an operation panel 90 for operating the image forming apparatus is provided on the front side of the automatic duplex document feeder 20.

FIG. 3 is a sectional view of the automatic duplex document feeder 20. In FIG. 1, an automatic double-sided document feeder 20 according to the present embodiment is configured such that a document set tray 21 on which a document M is placed and a document M set on the document set tray 21 are conveyed one by one. The document reading apparatus includes a transport reading unit 50 that reads an image on a document M, and a document discharge tray 40 that discharges the document M after reading the image.

The transport reading section 50 is provided with various rolls as various transport means along the transport path of the document M. First, the uppermost original M is placed at a position corresponding to the upper end of the original M set on the original set tray 21.
And a nudger roll (feeding roll) 22 for feeding out the original M. In the present embodiment, the nudger roll 22 comes into contact with the original M when sending out the original M, and is separated from the original set tray 21 by a predetermined distance when setting the original M. Reference numeral 23 denotes a stopper that aligns the leading end of the document M when the document M is set, and moves in the direction of the arrow when the document M is transported so as not to hinder the transport.

A document feed path α downstream of the nager roll 22 includes a feed roll 24 and a retard pad 25. The document M conveyed along the document feed path α is separated into one sheet. A mechanism is provided.

Further, on the downstream side of the separating mechanism, an original M
Take-away rolls 26 and 27 for transporting the original M are further provided. On the downstream side of the take-away rolls 26 and 27, the skew of the original M is temporarily stopped along the original reading path β by temporarily damaging the original M to be transported. There are provided registration rolls (registration rolls) 28 and 29 for removing (oblique feed), an image reading unit 30 for reading an image of the document M, and out rolls 33 and 34 for transporting the document M after image reading.

Here, the image reading section 30 is arranged to face the moving original platen glass 31 fixedly disposed to face the original reading path β, and to face the moving original platen glass 31 across the original reading path β. Platen roll 32,
A pressing member 32a is provided downstream of the platen roll 32 and prevents the document M conveyed through the image reading unit 30 from floating. The symbol Bm indicates the image reading beam from the reading unit 53.

A document discharge path γ for discharging the document M to the document discharge tray 40 is provided downstream of the out rolls 33 and 34, and the document discharge path γ Discharge rolls 35 and 36 for discharging the document M are provided.

Further, in the automatic document feeder according to the present embodiment, when reading an original M (double-sided original) having images formed on both sides, the original is reversed so that the images on both sides can be read in one process. A path δ is provided. This sheet reversing path δ is
4 and the take-away rolls 26, 27 are provided between the outlet side of the take-up rolls 4, and the reversing rolls 33, 37 are disposed in the paper reversing path δ. Here, in the present embodiment, the apparatus is downsized by using the out-roll 33 as a reversing roll.

Further, in the automatic document feeder according to the present embodiment, when the original M is a double-sided original, the inverted original discharge for reversing the original M and discharging it to the original discharge tray 40 when discharging the original. A path ε is provided. The inverted original discharge path ε is provided above the original discharge path γ, and the inverted original discharge paths ε are provided with inverted discharge rolls 38 and 39. By doing so, in the automatic document feeder according to the present embodiment, even when the (single-sided) image reading of the document M in which the image is formed on only one side is performed, the document having the image formed on both sides is read. When performing M (double-sided) image reading, the original M
However, the document is discharged to the document discharge tray 40 in the same order as the state of being set on the document set tray 21 and the front and back sides. In FIG. 3, among the rolls, ● indicates a driving roll, and ○ indicates a driven roll.

Various document detection sensors are provided in each of the document transport paths α to ε. Here, reference numeral 4
Reference numeral 1 denotes a set sensor for detecting the setting of the document M on the document set tray 21, reference numeral 42 denotes a feed sensor provided on the downstream side of the separating mechanism (feed roll 24 and retard pad 25) of the document carrying path α, and reference numeral 43 denotes a document reading path β. A registration sensor 44 is provided upstream of the registration rolls 28 and 29 of the document reading path 44, an out sensor provided upstream of the out rolls 33 and 34 of the document reading path β, and 45 is an upstream of the discharge rollers 35 and 36 of the document discharging path γ. Is a reversing sensor provided on the downstream side of the reversing rolls 33 and 37 of the document reversing path δ, and 47 is a reversing discharging sensor provided on the upstream side of the reversing discharge rollers 38 and 39 of the reversing document discharging path ε. is there.

Reference numeral 48 denotes a document guide provided along the document reading path β, and 49 denotes a plurality of guides provided in parallel with the feed sensor 42 to detect a length (document width) in a direction perpendicular to the transport direction of the document M. A size sensor 51 for fixing a document M, a platen glass for a fixed document as a document mounting plate for reading an image on the document M, and 52 is mounted on the platen glass 51 for the fixed document. Manuscript M
A document cover that holds Further, the reading unit 53 is provided so as to be movable along a line H in the figure, and can read an image of the document M conveyed by the conveyance reading unit 50, and further, the platen glass for the fixed document. It is also possible to read an image of the document M placed on the document 51.

Next, an arrangement position of each of the document detection sensors according to the present embodiment will be described. In the present embodiment, the feed sensor 42, the registration sensor 43, the out sensor 44, the discharge sensor 45, the reversing sensor 46, and the reversing discharge sensor 47 are arranged in a direction along the transport direction of the document M, that is, as shown in FIG. It is arranged on a straight line C parallel to the transport direction.

The feed sensor 42 and the size sensor 49 (specifically, the first size sensor 49a, the second size sensor 49b, and the third size sensor 49c), as shown in FIG. It is disposed on a direction orthogonal to the direction, that is, on a straight line D orthogonal to the straight line C. In the present embodiment, the detection signal from each of the sensors 42 and 49 is combined to determine the length in the direction orthogonal to the conveyance direction of the original M (the original The width of the original M is determined, and the size of the original M (the length of the original M in the transport direction) is determined from this.

This will be described with reference to FIGS. 4 and 5. For example, in the case of JIS B5 size vertical feed (B5S), only the feed sensor 42 is turned on, and in the case of JIS 4 size vertical feed (A4S), the feed sensor 42 and the feed sensor 42 are turned on. One size sensor 49a is turned on. Also, JISB5
The feed sensor 42 and the second size sensor 49b are turned on in the case of the size lateral feed (B5L) or the JIS B4 size, and the feed sensor 42 and the third size sensor 49c are turned on in the case of the JIS A4 size transverse feed (A4L) or the JIS 3 size. Therefore, the size of the document M (the length of the document M in the transport direction) is determined in this manner.

In the present embodiment, the size sensor 49 is detected in the order of 49c → 49b → 49a, and after the outer sensor (for example, 49c) detects ON, the other sensors (49a, 49b ), The detection time is shortened and the detection process is made more efficient.

As shown in FIG. 6A, the operation panel 90 includes a touch panel display 91 for instructing various functions and necessary operations, a communication / job confirmation button 92 for confirming copy, fax, and print states. A setting confirmation button 93 for confirming the set functions, a function switching button 94 for switching the screen of the touch panel display 91 for each function, a numeric keypad 95 for inputting the number of copies / fax number and numerical values for setting various functions, reading of the original M A start button 96 to be pressed at the start, a stop button 97 for canceling a copy operation or a communication operation,
Reset button 98 to cancel all settings and return to initial screen, one-touch button 9 for storing fax number
9a and a job memory button 9 in which an operation procedure is registered
9b and the like.

Further, the conveyance control of the automatic document feeder according to the present embodiment is performed by the control device 100 shown in FIG. In FIG.
The document detection signals from the set sensor 41, the feed sensor 42, the registration sensor 43, the out sensor 44, the ejection sensor 45, the reversing sensor 46, and the reversing ejection sensor 47 are input to the CPU 102 via the input interface 101, and then the CPU 102 After executing the control program stored in the ROM 103 and appropriately performing data processing with the RAM 104, the output interface 10
5, through the nager roll 22, the feed roll 2
4, a feed motor 81 for driving the takeaway roll 26, a nudger solenoid exciter 70 for moving the nudger roll 22, and a feed clutch 24 provided between the feed motor 81 and the feed roll 24.
a, a main motor 82 for driving a drive roll other than the nager roll 22, the feed roll 24, and the takeaway roll 26; a registration clutch 28a provided between the main motor 82 and the registration roll 28; A drive signal is sent to a discharge clutch 35a provided between the discharge roller 35 and a discharge solenoid 35b for bringing the discharge roll 35 into and out of contact with the discharge roll 36 (see FIG. 8).
As shown in FIG. 8, between the feed motor 81 and the nudger roll 22, the take away roll 26,
Between the main motor 82 and the platen roll 32, the out roll (reversing roll) 33, and the reversing discharge roll 38,
An interrupter such as a clutch is not connected, and is interlocked with the rotation of each motor.

Next, a document feeding process of the automatic document feeder according to the present embodiment will be described. Here, a case of transporting an A4S-size original M (standard-size original: transport direction length L1 = 297 mm, direction length W1 = 210 mm orthogonal to the transport direction) shown in FIG. 11A will be described. .

(1) Single-sided Document Feeding Process The document feeding process of three documents M on which a read image is formed on only one side will be described with reference to timing charts shown in FIGS. 3, 8, and 9.

First, when a document M is set on the document set tray 21 of the automatic document feeder, the presence of the document M is detected by the set sensor 41, and the automatic document feeder is set in an operable state. Subsequently, when a start button 96 (see FIG. 6A) of the operation panel 90 is pressed, an exciting current flows through a solenoid (not shown) by the nager solenoid exciter 70, whereby the nager roll 22 The uppermost original M in the set of originals is brought into contact with the original, and the original M can be sent out. At the same time when the start button 96 is pressed, the feed motor 81 is also started, and the nudger roll 22 is driven accordingly, and the uppermost original M is sent out.

After the start button has been pressed, T0
After a lapse of time, the feed clutch 24a is engaged, and the feed roll 24 is driven. This time T0 is set to a period slightly longer than the time required for stable rotation after the feed motor 81 starts up and for the nudger roll 22 to reliably contact the original bundle. Then, the document M sent out by the nudger roll 22 is separated by a separating mechanism, ie, a feed roll 24 and a retard pad 25.
Are separated one by one and further conveyed.

Next, when the document M reaches the portion facing the feed sensor 42 through the separating mechanism, the feed sensor 42 is turned on. After this time T1, the feed clutch 24a is disengaged, and the driving of the feed roll 24 is stopped. This T1 is set to a period slightly longer than a period required for the leading end of the fed document M to be held between the takeaway rolls 26 and 27. At this point, the takeaway rolls 26 and 27 are rotating (because the interlocked feed motor 81 is activated), and the original M
After the driving of the feed roll 24 is stopped, the feed roll 24 is conveyed by the driving force of the take away roll 26. Further, the feed roll 24 with the feed clutch 24a disengaged is freely rotatable, and is driven to rotate as the document M is conveyed.

Subsequently, the original M is taken away from the take-away roll 2.
When the sheet passes through 6 and 27 and reaches the portion facing the registration sensor 43, the registration sensor 43 is turned on, and the main motor 82 is started accordingly. Further, after a lapse of T2 time since the registration sensor 43 is turned on, the driving of the feed motor 81 is stopped, and accordingly, the driving of the take away roll 26 is stopped. This T2 is set to a period in which the original M can be abutted against the registration rolls 28 and 29 to form a predetermined loop in order to prevent the original M from being skewed.

Then, T3 time after the driving of the feed motor 81 is stopped, the registration clutch 28a is engaged, and the registration roll 28 is driven. Further, after T4 time from the start of rotation of the registration roll 28, the drive of the feed motor 81 is restarted, and
6 is also driven again. This T4 is a resist roll 28
The period is set to such an extent that the loop formed on the document M is eliminated with the rotation of. At this time, the feed motor 81 is driven to a normal rotation speed after being temporarily accelerated suddenly, and the takeaway roll 26 is also driven in synchronization with this. This is because the document M is conveyed while forming a slight loop. Then, the original M
The image reading unit 30 is transported at a constant speed by the platen roll 32 and the registration rolls 28 and 29, and the image on the document M is read by the image reading beam Bm from the reading unit 53.

Subsequently, when the trailing end of the document M passes through the portion facing the registration sensor 43, the registration sensor 43 is turned off. After T5 time, the registration clutch 28a is disengaged and the driving of the registration roll 28 is stopped. This T5 is set slightly longer than the period until the trailing edge of the document M passes through the registration rolls 28 and 29.

The document M for which image reading has been completed is conveyed by the out rolls 33 and 34 and the discharge rolls 35 and 36 and discharged onto the document discharge tray 40.

Here, if the next original M does not exist, the ending operation is immediately started. If the next original M exists, the image of the first original M is being read and the feed sensor 42 Is turned off, that is, the first original M
When the trailing end of the document M has passed through the portion facing the feed sensor 42, the feed clutch 24a is engaged, and the second document M is separated and transported. When the second document M passes through the separating mechanism and reaches the portion facing the feed sensor 42, the feed sensor 42 is turned on. After T6 hours, the feed clutch 24a is disengaged, and the drive of the feed roll 24 is started. Is temporarily stopped. This T6 is set to a period during which the leading edge of the second document M is transported to a position immediately before the take away rolls 26 and 27.

Subsequently, after the registration sensor 43 is turned off, that is, T10 hours after the trailing end of the first document M passes through the portion facing the registration sensor 43, the feed clutch 24a is engaged again, and the feed roll 24 Is restarted. This T10 is set to be slightly longer than a period required for the trailing edge of the first document M to pass through the registration rolls 28 and 29. Thereafter, the second document M is read in the same manner as the first document M described above, and is discharged onto the document discharge tray 40 after the image reading is completed.

Further, the third original M is conveyed and image-read by the same process as that of the second original M, but the third original M is the last original M in this process. Therefore, when the registration sensor 43 is turned off, that is, when the trailing end of the third original M is
At the point in time when the feed motor 81 has passed through the opposing portion, the drive stop of the feed motor 81 is started and then stopped. The registration sensor 4
T8 time after the switch 3 is turned off, an exciting current is supplied by the nudger solenoid exciter 70, whereby the nudger roll 22 is pulled up from the set state (however, the document M does not exist) to the upper side. Become. The trailing end of the third (final) document M is the discharge sensor 45.
The driving of the main motor 82 is stopped T9 time after the discharge sensor 45 detects that the vehicle has passed through the opposing portion, and a series of processes is ended. This T9 is set to be slightly longer than a period until the third (final) document M is discharged onto the document discharge tray 40.

In the one-sided document feeding process, the sheet reversing path δ is not used, and therefore, the reversing sensor 46 and the reversing discharge sensor 4 used in the process of reversing the document M are used.
7. The discharge clutch 35a and the discharge solenoid 35b are not used in the one-sided original feeding process.

(2) Double-sided Document Feeding Process The document feeding process of the document M having the read images formed on both sides will be described with reference to the timing charts shown in FIGS. 3, 8, and 10.

First, when the document M is set on the document set tray 21 of the automatic document feeder, the presence of the document M is detected by the set sensor 41, and the automatic document feeder is set in an operable state. Subsequently, when a start button 96 (see FIG. 6A) of the operation panel 90 is pressed, an exciting current flows through a solenoid (not shown) by the nager solenoid exciter 70, whereby the nager roll 22 The uppermost original M in the set of originals is brought into contact with the original, and the original M can be sent out. At the same time when the start button 96 is pressed, the feed motor 81 is also started, and the nudger roll 22 is driven accordingly, and the uppermost original M is sent out.

Also, after the start button is pressed, T0
After a lapse of time, the feed clutch 24a is engaged, and the feed roll 24 is driven. This time T0 is set to a period slightly longer than the time required for stable rotation after the feed motor 81 starts up and for the nudger roll 22 to reliably contact the original bundle. Then, the document M sent out by the nudger roll 22 is separated by a separating mechanism, ie, a feed roll 24 and a retard pad 25.
Are separated one by one and further conveyed.

Next, when the document M passes through the separating mechanism and reaches a portion facing the feed sensor 42, the feed sensor 42 is turned on. After this time T1, the feed clutch 24a is disengaged, and the driving of the feed roll 24 is stopped. This T1 is set to a period slightly longer than a period required for the leading end of the fed document M to be held between the takeaway rolls 26 and 27. At this point, the takeaway rolls 26 and 27 are rotating (because the interlocked feed motor 81 is activated), and the original M
After the driving of the feed roll 24 is stopped, the sheet is conveyed by the driving force of the take away roll 26. Further, the feed roll 24 with the feed clutch 24a disengaged is freely rotatable, and is driven to rotate as the document M is conveyed.

Subsequently, the original M is taken away from the take-away roll 2.
When the sheet passes through 6 and 27 and reaches the portion facing the registration sensor 43, the registration sensor 43 is turned on, and the main motor 82 is started accordingly. Further, after a lapse of T2 time since the registration sensor 43 is turned on, the driving of the feed motor 81 is stopped, and accordingly, the driving of the take away roll 26 is stopped. This T2 is set to a period during which the original M can be abutted against a registration roll to form a predetermined loop in order to prevent the original M from being skewed.

Then, T3 time after the driving of the feed motor 81 is stopped, the registration clutch 28a is engaged, and the registration roll 28 is driven. Further, after T4 time from the start of rotation of the registration roll 28, the drive of the feed motor 81 is restarted, and
6 is also driven again. This T4 is a resist roll 28
The period is set to such an extent that the loop formed on the document M is eliminated with the rotation of. At this time, the feed motor 81 is driven to a normal rotation speed after being temporarily accelerated suddenly, and the takeaway roll 26 is also driven in synchronization with this. This is because the document M is conveyed while forming a slight loop. Then, the original M
The image reading unit 30 is transported at a constant speed by the platen roll 32 and the registration rolls 28 and 29, and the image (front surface image) on the document M is read by the image reading beam Bm from the reading unit 53.

Subsequently, when the trailing end of the document M passes through the portion facing the registration sensor 43, the registration sensor 43 is turned off, and after T5, the registration clutch 28a is disengaged, and the driving of the registration roll 28 is stopped. This T5 is set slightly longer than the period until the trailing edge of the document M passes through the registration rolls 28 and 29.

Then, the original M whose surface image reading has been completed
Is conveyed toward the document discharge tray 40 by the out rolls 33 and 34 and the discharge rolls 35 and 36. When the rear end of the document M passes through the portion facing the out sensor 44,
The out sensor 44 is turned off, and after T11, the driving of the main motor 82 is stopped, and accordingly, the driving of the out roll 33 and the discharge roll 35 is also stopped. This T11 is set to a period in which the trailing end of the document M is discharged from the nip of the out rolls 33 and 34 and reaches the read document reversal position indicated by the reference sign R1 in FIGS.

Also, at the same time when the main motor 82 is completely stopped, the discharge clutch 35a is switched to be set in a state of being rotated in the reverse direction. After the time T12, the main motor 82 is restarted, and accordingly, the reversing roll (out roll) 33 and the discharge roll 35 are driven. At this time, the discharge clutch 35a has already been switched, the discharge roll 35 is driven in the opposite direction, and the document M is turned over by a path switching mechanism (not shown) arranged near the position R1. It is transported toward the path δ.

When the leading end of the document M reaches the portion facing the reversing sensor 46, the reversing sensor 46 is turned on,
At the same time, the discharge solenoid 35b is driven to release (release) the nip of the discharge rolls 35 and 36, and the feed motor 81 is restarted, so that the take-away roll 2
6 is driven.

Subsequently, the leading edge of the document M is again
When the counter sensor 3 is reached, the registration sensor 43 is turned on, and after T13, the driving of the feed motor 81 is stopped and the driving of the takeaway roll 26 is stopped.
At the same time, the driving of the main motor 82 is stopped, and the driving of the reversing roll 33 and the discharge roll 35 is stopped. This T13 is set to a period during which a predetermined loop can be formed by abutting the document M against a registration roll in order to prevent skew of the document M, similarly to T2. On the other hand, after T14 time since the registration sensor 43 is turned on, the discharge clutch 35a is switched again and set to a state in which it can be rotated in the forward direction again.

Then, T15 time after the driving of the feed motor 81 and the main motor 82 is stopped, the feed motor 81 is restarted, and the takeaway roll 26 is driven again. Further, the main motor 82 is restarted, the registration clutch 28a is also engaged, and the registration roll 28 is driven. Thereafter, the document M is conveyed at a constant speed through the image reading unit 30 by the platen roll 32 and the registration rolls 28 and 29, and the back surface image on the document M is read by the image reading beam Bm from the reading unit 53.

Subsequently, when the trailing edge of the document M passes through the portion facing the registration sensor 43, the registration sensor 43 is turned off, and after T5, the registration clutch 28a is disengaged and the driving of the registration roll 28 is stopped. In addition, the registration sensor 43
After T16 hours from the turning off, the discharge solenoid 35b
Is driven to nip the discharge rolls 35 and 36. This T16 is set to a period until the leading edge of the document M reaches the discharge rollers 35 and 36.

The original M whose image has been read is conveyed toward the original discharge tray 40 by the out rolls 33 and 34 and the discharge rolls 35 and 36. When the vehicle passes through the opposing portion, the out sensor 44 is turned off, and after T17, the driving of the main motor 82 is stopped.
The driving of 3 and the discharge roll 35 is also stopped. This T17
Is set to a period in which the rear end of the document M is discharged from the nip of the out rolls 33 and 34 and reaches the discharged document reversal position indicated by the reference sign R2 in FIGS.

At the same time when the main motor 82 is completely stopped, the discharge clutch 35a is switched to be set in a state of being rotated in the reverse direction. After the time T12, the main motor 82 is restarted, and accordingly, the discharge roll 35 and the reverse discharge roll 38 are driven. At this time, the discharge clutch 35a is switched, the discharge roll 35 is driven in the reverse direction, and the original M is discharged by the path switching mechanism (not shown) disposed near the position R2. The document is conveyed toward the path ε and discharged to the document discharge tray 40. During this time, the original M
Reaches the portion facing the reversing discharge sensor 47,
The reverse discharge sensor 47 is turned on, and at the same time, the discharge clutch 35a is switched to be set in a state of being rotated in the forward direction.

Here, if the next original M does not exist, the end operation is immediately started. However, if the next original M exists, the reading operation of the back image of the first original M is in progress. When the registration sensor 43 is turned off, that is, when the rear end of the inverted first document M passes through the portion facing the registration sensor 43, the feed clutch 24a is engaged, and the second document M is separated. He is transported. Then, when the second document M passes through the separation mechanism and reaches the portion facing the feed sensor 42, the feed sensor 42 is turned on. After T18 hours, the feed clutch 24a is disengaged, and the drive of the feed roll 24 is started. Is temporarily stopped. In this T18, the second original M is taken away by the take-away roll 26,
This is set to a period during which the sheet is conveyed to the position immediately before 27.

Subsequently, T19 hours after the first original M arrives at the portion facing the reverse discharge sensor 47 and the reverse discharge sensor 47 is turned on, the registration clutch 28a is engaged, and the registration roll 28 is moved. Driven. Further, after T4 time from the start of rotation of the registration roll 28, the drive of the feed motor 81 is restarted, and
6 is also driven again. Thereafter, the above-described process is repeated to execute the double-sided image reading process.

In the above-described one-sided original feeding process and the two-sided original feeding process, each original conveying path α
When the document M is jammed within the range of ~ ε, the feed motor 81 and the main motor 82 are stopped immediately,
It is necessary to reduce as much as possible the damage and damage to the document M having the jam.

Accordingly, in the present embodiment, the original M is fed from the feed sensor 42, the registration sensor 43, and the out sensor 4.
4. The jam is detected by monitoring the passage time passing through the discharge sensor 45, the reversing sensor 46, and the reversing discharge sensor 47.

Therefore, in order to monitor a jam in the document feeding process, information on the length of the document M in the transport direction is required. Therefore, in the present embodiment,
In the case of a fixed size original M such as an A4S original, a predetermined length of time has elapsed since the feed sensor 42 was turned on, and the size sensor 49 detects the length of the original M in the direction perpendicular to the transport direction. The size of the document M is specified from the detection result, and information on the length of the document M in the transport direction is obtained. Here, the reason why the timing of the size detection is slightly shifted from the ON time of the feed sensor 42 is to prevent erroneous size detection due to the skew of the document M.

This will be described in detail. For example, A4S
In the case of a document M having a size, as shown in FIG. 4, the feed sensor 42 and the first size sensor 49a are turned on.
It is determined that the size is S. The feed sensor 42, the registration sensor 43, the out sensor 44, the discharge sensor 45, the reversing sensor 46, and the reversing discharge sensor 47 are determined based on the relationship between the length (297 mm) of the A4S size document in the transport direction and the transit time including the stop time. Is set. However, among these sensors, the reversing sensor 4
6 and the jam timer value of the reversing discharge sensor 47 are set only when the double-sided document feeding process is executed.

For example, in the case of the out sensor 44 in which the original M always passes at a constant speed in the one-sided original feeding process and the two-sided original feeding process, the jam timer value is set as shown in FIG.
As shown in FIG. 1A, the time TJ1 is set to a value obtained by adding a margin to the minimum time TL1 required for the length L1 of the document M to pass in the transport direction, and the time required for the document M to pass through the out sensor 44. Is greater than the jam timer value TJ1, the jam determination of the document M and the accompanying stop of the feed motor 81 and the main motor 82 are executed.
For other sensors in which the document M temporarily stops while passing through the portion facing the sensor, the jam timer value is set based on the passing time including the stop time.

In reading an image of a fixed size original M in this manner, no problem arises because the jam timer value is automatically set in accordance with the size of the original M. on the other hand,
An X-size original M shown in FIG. 11B (an irregular-size original: here, the length L2 in the transport direction = 364 mm (> L)
1), the length W2 = 210 mm in the direction perpendicular to the transport direction (=
W1)), the length W2 of the X-size document M in the direction perpendicular to the transport direction is the same as the above-described W1 of the A4S size document. Is misrecognized as the A4S size document, the jam timer value is set to TJ1 for the A4S size, and a jam is erroneously detected on the rear end side of the document M, and the apparatus stops. .

Therefore, in the present embodiment, when reading an image of the original M of such an irregular size, before the image reading is started, the length L of the original M in the transport direction and the direction orthogonal to the transport direction are set. The image reading is performed after the length W is input and the jam timer value is changed according to the input length L in the transport direction.

This will be described with reference to the flowcharts shown in FIGS. First, the operator selects the irregular document feed mode. This will be specifically described as follows. When the operator touches “Copy” on the touch panel display 91 of the operation panel 90 shown in FIG. 6A, a basic copy screen shown in FIG. 6B appears. When the operator touches “Copy function list” on this screen, A copy function list screen shown in FIG. 6C appears. By touching "non-standard-size original feed", the non-standard-size original feed screen shown in FIG. 6D appears, and the non-standard-size original feed mode is selected.

Next, the operator inputs the size of the document using the ten keys 95 on the screen shown in FIG. Here, the length L of the original M in the transport direction is the original size (width).
In addition, the length W in the direction orthogonal to the transport direction of the document M corresponds to the document size (vertical).

When the input of the size of the original M is completed, the selection of the transfer paper and the calculation of the jam timer value are performed based on the input size. Here, the selection of the transfer paper is performed when the automatic paper selection mode is selected, which includes the input transport direction length L and the direction length W orthogonal to the transport direction, and Based on other setting conditions (e.g., enlargement / reduction magnification, etc.), the smallest one of the sheets accommodated in the sheet trays 11 to 14 (see FIG. 2) which does not lack the image area of the document M is automatically selected. To choose. The jam timer value is calculated for each of the sensors 42 to 47 from the relationship between the input length L in the transport direction and the passing time including the stop time. For example, in the case of the above-described out sensor 44, this value is a value obtained by adding a margin to the minimum time TL2 required for the length L2 of the document M to pass in the transport direction as shown in FIG. It becomes TJ2.

Then, the jam timer value of each of the sensors 42 to 47 is changed based on the calculation result. afterwards,
When the operator places the bundle of originals on the original set tray 21 and subsequently presses the start button 96 (see FIG. 6A) of the operation panel 90, the reading of the original M is started from the first sheet.

In the present embodiment, since the jam timer values of the sensors 42 to 47 are changed according to the length L of the document M in the transport direction, the stoppage of the apparatus due to the erroneous detection of the jam is effectively avoided. Therefore, even an original M of an irregular size can be read using the automatic double-sided original feeder 20.

Further, since the jam timer value is changed before the start of reading, even when a jam actually occurs in the document conveyance paths α to ε, the detection of the document jam and the stop of the apparatus accompanying the jam are performed. And the damage and breakage of the document M can be minimized.

Furthermore, when reading a plurality of non-standard-size originals of the same size, the size of the original M need only be input once at first, so that the operation time of the operator can be greatly reduced, and the efficiency can be reduced. Can be increased. Similarly,
When reading a non-standard-size original on which a double-sided image is formed, the size of the original M only needs to be input once at first, so that the operation time of the operator can be greatly reduced and efficiency can be improved. .

Embodiment 2 The present embodiment is substantially the same as Embodiment 1, except that the size of the document M is detected instead of inputting the size of the document M. Note that, of the components of the image forming apparatus according to the present embodiment, the same components as those of the image forming apparatus according to the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed descriptions thereof will be given here. Description is omitted.

In this embodiment, an original M of an irregular size
In the case of reading an image, before the image reading is started, the original M is placed on the fixed original platen glass 51 and the size is read, that is, the length L in the transport direction of the original M and the length perpendicular to the transport direction. W is detected, and the image reading is performed after the jam timer value is changed according to the detected length L in the transport direction.

This will be described with reference to the flowcharts shown in FIGS. 6, 13 and 14. First, the operator selects the irregular document feed mode. This will be specifically described as follows. When the operator touches “Copy” on the touch panel display 91 of the operation panel 90 shown in FIG. 6A, a basic copy screen shown in FIG. 6B appears. When the operator touches “Copy function list” on this screen, A copy function list screen shown in FIG. 6C appears. Then, by touching "non-standard-size original feed", the non-standard-size original feed screen shown in FIG. 13A appears, and the non-standard-size original feed mode is selected.

Next, the operator places the original M on the fixed original platen glass 51 shown in FIG. 13B and presses it with the original cover 52, and then displays the screen shown in FIG.
Touch “Start reading”. Then, in FIG. 3, the reading unit 53 scans the document M on the fixed document platen glass 51 once, and detects the length L of the document M in the transport direction and the length M in the direction perpendicular to the transport direction.

When the detection of the size of the original M is completed, the selection of the transfer paper and the calculation of the jam timer value are performed based on the detected size. The selection of the transfer paper and the calculation of the jam timer value are the same as in the first embodiment.

Then, the jam timer value of each of the sensors 42 to 47 is changed based on the calculation result. afterwards,
The operator places the bundle of originals on the original set tray 21 this time, and then starts the start button 96 (FIG. 6) on the operation panel 90.
(See (a)), the reading of the document M is started from the first sheet.

With this configuration, the same effect as in the first embodiment can be obtained.

Third Embodiment The third embodiment is substantially the same as the second embodiment, except that the size of the document M is detected by a method different from that of the second embodiment. Note that, of the components of the image forming apparatus according to the present embodiment, the same components as those of the image forming apparatus according to the second embodiment are denoted by the same reference numerals as those in the second embodiment, and detailed description thereof will be given here. Description is omitted.

In this embodiment, an original M of an irregular size
Before reading the image, one document M is transported from the document set tray 21 to read the size, that is, the length L in the transport direction of the document M and the length W in the direction orthogonal to the transport direction. Is detected, and the image reading is performed after the jam timer value is changed according to the detected length L in the transport direction.

This will be described with reference to the flowcharts shown in FIGS. 6, 15 and 16. First, the operator selects the irregular document feed mode. This will be specifically described as follows. When the operator touches “Copy” on the touch panel display 91 of the operation panel 90 shown in FIG. 6A, a basic copy screen shown in FIG. 6B appears. When the operator touches “Copy function list” on this screen, A copy function list screen shown in FIG. 6C appears. Then, by touching "non-standard-size original feed", the non-standard-size original feed screen shown in FIG. 15A appears, and the non-standard-size original feed mode is selected.

Next, the operator places the document M on the document set tray 21 shown in FIG. 15B, and touches "Start reading" on the screen of FIG. 15A. Then, in FIG. 3, the jam timer values of the sensors 42 to 45 disposed in the respective document conveying paths α to ε are temporarily changed to the maximum values corresponding to the maximum size that can be read by this apparatus. . Then, the first document M is transported at a constant speed,
For example, the length L of the document M in the transport direction is obtained from the passing time of the out sensor 44 and the transport speed, and the length W in the direction orthogonal to the transport direction of the document M is detected by the feed sensor 42 and the size sensor 49.

When the detection of the size of the original M is completed, the selection of the transfer paper and the calculation of the jam timer value are performed based on the detected size. The selection of the transfer paper and the calculation of the jam timer value are the same as in the first embodiment.

Then, the jam timer value of each of the sensors 42 to 47 is changed based on the calculation result. afterwards,
The operator returns the original M used for the size detection to the original bundle placed on the original set tray 21, and then operates the operation panel 90.
By pressing the start button 96 (see FIG. 6A), the reading of the original M is started from the first sheet.

With this configuration, the same effects as those of the first and second embodiments can be obtained.

In this embodiment, the image is not read at the time of transporting the first document M for detecting the size. However, the image may be read at the same time.

[0096]

As described above, according to the present invention,
Before starting reading, size information on the length of the document in the transport direction is acquired, and the document transport process is controlled based on this information.Therefore, non-standard size documents can be used without lowering productivity or reliability. Can be transported and read.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory diagrams showing an outline of an automatic document reading apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram showing Embodiment 1 of the image forming apparatus to which the automatic document reading apparatus according to the present invention is applied;

FIG. 3 is a schematic configuration diagram of an automatic double-sided document feeder as an automatic document reading device.

FIG. 4 is an explanatory diagram showing an arrangement position of each sensor.

FIG. 5 is a table showing a relationship between detection results of a feed sensor and a size sensor and a determined document size.

FIG. 6A is an explanatory diagram illustrating an example of an operation panel, and FIGS. 6B to 6D are diagrams illustrating an example of a screen of a touch panel display.

FIG. 7 is a block diagram of a control device.

FIG. 8 is a schematic configuration diagram of a transport drive system.

FIG. 9 is a timing chart of a one-sided document feeding process.

FIG. 10 is a timing chart of a double-sided document feeding process.

11A is a schematic diagram illustrating an example of a standard size document, and FIG. 11B is a schematic diagram illustrating an example of a non-standard size document.

FIG. 12 is a flowchart according to the first embodiment.

13A is a schematic diagram illustrating an example of a screen of a touch panel display according to Embodiment 2, and FIG. 13B is a schematic diagram illustrating a method of setting a size detection document.

FIG. 14 is a flowchart according to the second embodiment.

15A is a schematic diagram illustrating an example of a screen of a touch panel display according to the third embodiment, and FIG. 15B is a schematic diagram illustrating a method for setting a document for size detection.

FIG. 16 is a flowchart according to the third embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conveying means, 2 ... Reading means, 3 ... Input means, 4, 6 ...
Control means, 5: detecting means, L: length in conveyance direction, M: original, S: original detection sensor

Continued on front page F-term (reference) 2H027 DA38 DB07 DB09 FA04 FA22 2H076 BA72 BB04 5C062 AA02 AA05 AB17 AB29 AB40 AC13 AC67 AC69 AF10 BA00 5C072 AA01 BA13 BA20 LA02 NA01 NA08 RA01 RA20 XA01 9A001 HH34 JJ28

Claims (5)

[Claims] 1. An automatic document reading apparatus comprising a conveying means for conveying a document and a reading means for reading an image of the conveyed document, an input means for inputting a length of the document in the conveying direction before starting reading. An automatic document reading apparatus comprising: a control unit configured to control a reading process of the document based on size information from the input unit. 2. An automatic document reading apparatus comprising a conveying means for conveying a document and a reading means for reading an image of the conveyed document, wherein a detecting means for detecting the length of the document in the conveying direction before starting the reading. An automatic document reading apparatus comprising: a control unit that controls a reading process of the document based on size information from the detection unit. 3. An automatic document reading apparatus according to claim 2, wherein said detecting means detects the size of a document placed stationary on a document placing plate. Document reading device. 4. The automatic document reading apparatus according to claim 2, wherein said detecting means detects a size of a moving document provided in a document transport path by said transport means. Automatic document reading device. 5. The automatic document reading apparatus according to claim 1, wherein the control unit is configured to select the first first sheet under a condition that a mode of reading images of a plurality of sheets of the same size is selected. An automatic document reading apparatus for controlling a reading process of a second or subsequent document based on document size information.