JP3462022B2 - Automatic document feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] TECHNICAL FIELD The present invention relates to a copier, a facsimile
Applied to image processing devices such as millimeters and scanners
For details on automatic document feeders, see
Automatic document feeder that can determine document size during
About the installation. [0002] 2. Description of the Related Art Conventionally, copying machines, facsimile machines,
For an image processing device such as a canner device,
Documents are separated one by one from the bundle of documents placed on
Transporting the image data to the image processing position and performing image processing such as reading image data.
The document is ejected to the output tray after
You. A document feeder of a conventional automatic document feeder of this type is used.
For example, the size of the document
Originals on original guides such as side guides and back guides
The document guide position by abutting the width and rear edges of
Detected and compared with standard size of A3, B4, A4 etc.
There is a known method for determining the original size.
Based on the size of the original,
The automatic selection condition and the condition for changing the paper size are set. Further, Japanese Patent Application Laid-Open No. 1-163762 discloses
Is the instruction lever along the guide on the original glass surface of the copier.
And a potentiometer to indicate the
Scan the bar position with a potentiometer
A method for determining the size is described. In addition, other
As a detection method, one document provided in the document transport path
The detection sensor detects the leading and trailing edges of the document, and
Counts the rotation pulses of the feed motor while the
By counting, the length of the document in the transport direction is detected, and
The size of the document (for example, A4, B4, A
3,...) Is also known. [0005] However, the original document
Adjust the position of the guide and indicator lever corresponding to the width end and rear end positions.
In the detection method, the configuration for document size detection
Many parts, complicated mechanism, and operator
Guide and lever adjustment work is required, so size detection
Adjustment work is complicated. Also guide
Readings vary greatly depending on how the lever and lever are adjusted
The document size judgment range in advance.
The type of document size that can be determined
There was a problem that the size was limited to the standard size only. Further
The original size is determined by one original detection sensor in the conveyance path.
In the method of detecting the
Reading of the length of the original in the transport direction due to
Variation in the document size, the
There was a problem that could not be done. The present invention solves the above-mentioned problems, and
Eliminates sources of variation in size readings
There are many types of document sizes that can be determined with a simple configuration,
Original size due to slippage or deflection of the original being transported
Suppress variations in readings to determine the correct document size.
To provide an automatic document feeder capable of performing
And for the purpose. [0007] According to the first aspect of the present invention,
In order to solve the above problems, originals are transported along a predetermined transport path.
A document conveying means to be fed, and a
And the original conveyed by the original conveyer is detected.
First document detecting means for performing
Provided separately in the transport path behind the transport direction.
Driving the second document detecting means and the document conveying means.
Pulse signal in synchronization with the operation of the driving means for
A pulse generating means for outputting the first and second originals;
The pulse generation means based on the detection signal from the output means.
Pulse counting means for counting pulse signals output from
And the number of pulses counted by the pulse number counting means.
A document that undergoes a fixed correction process and determines the size of the document
Starting the counting of the size determining means and the pulse number counting means.
And the end operation, and the
Control means for controlling the arithmetic processing related to the pulse number correction processing of the stage
With stepsAnd the control means includes the pulse number counting means.
Detects the leading edge of the document by the first document detecting means.
Counting is started at the point in time when the trailing edge of the original is detected.
At the point when counting ends and obtains the first pulse number.
And the second document detecting means controls the
Counting starts when the leading edge of the manuscript is detected.
When the trailing edge is detected, the counting ends and the second pulse number is counted.
And the document size determination means is
The first and second numbers counted by the pulse number counting means.
Control to average the number of pulses.Features and
are doing. In the automatic document feeder according to the first aspect,
According to the configurationDocument scanning upstream and downstream of the document transport path
Output sensors detect the leading and trailing edges of the document and
Counts, compare and average these counts
Pulse that corresponds to the length of the original in the transport direction
Calculate the document size and compare the
Since it can be determined,
Using the two different count values to determine the document size
Can cause slippage and bending during document transport.
The variation and error of the count value are detected by one sensor.
Can be reduced compared to the case of
Size determination can be performed. [0009] [0010] [0011] [0012] [0013] [0014] [0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an automatic document feeder according to the present invention will be described.
Will be described with reference to examples. First, in claim 1
FIG. 1 shows a basic configuration of the automatic document feeder of the present invention.
Will be explained. In FIG. 1, reference numeral 100 denotes an automatic document feeder.
10 is a feed driven by the feed motor 10m.
An original that has paper and separation rollers and is placed on the document
A paper feed unit that feeds originals one by one from a bundle of documents,
Roller group or conveyor driven by motor 20m
It has a belt and feeds the fed document to a predetermined image processing unit, etc.
The transport unit 30 for transporting is driven by a discharge motor 30m.
Documents to the paper output tray
This is a paper discharge unit. Here, the paper feed unit 10, the transport unit 20, and the discharge unit
The paper unit 30 is provided with a paper feed motor 10 m,
The motor 20m and the paper discharge motor 30m correspond to a driving unit.
You. 40a and 40b are the leading edge of the conveyed document and
An original that detects the trailing edge, etc., and detects the presence or absence of the
A document detection sensor (first and second document detection means);
For example, upstream and downstream of the transport path of the sheet feeding unit 10
Are provided at a distance from each other. And 50 is an automatic document carry
A controller (control means) for controlling each configuration of the feeding device 100
Step), the operation of the motor for transporting the original
A pulse generator (pulse generator) that outputs a pulse signal in synchronization
Source) 50a and the original detection sensors 40a and 40b
Output from the pulse generator 50a based on the detection signal of
Pulse counter (pulse count)
Counting means) 50b and counting by a predetermined pulse counting procedure.
Corrects the counted value, and sets the paper size
Original size judging section (original size)
(Document size determination means) 50c. Where
As a pulse signal counted by the Luz counter 50b
For example, a stepping motor is
In a configuration that uses a motor,
May be used or DC motor (DC motor)
If the motor is used as the driving means, check the motor rotation.
Alternatively, an output signal from the output encoder may be used. What
Reference numeral 60 denotes an operation panel or an operation panel for operating a document conveying operation or the like.
Operation unit that includes a liquid crystal display panel that displays information to the
70 is an image to which the automatic document feeder 100 is applied.
Image processing equipment (copier, facsimile, scanner
Interface that inputs and outputs control signals to and from the
You. Next, the automatic document feeder according to the present invention is applied.
FIG. 2 shows a schematic configuration of an image processing apparatus that can be used.
I will explain. In this embodiment, the image processing apparatus
Shows a case where the present invention is applied to a copying machine. In FIG. 2, 1
Is a copier with double-sided copying function as an image processing device
There is a contact glass 1a on the upper surface of the copying machine 1.
Is provided. In addition, an automatic document feeder is located above the copying machine 1.
Feeder 100 is provided, and the automatic document feeder
A copying machine 100 opens and closes the contact glass 1a.
1 is connected via a hinge (not shown) or the like. The automatic document feeder 100 includes a plurality of originals.
As a document table on which a document bundle 80 composed of manuscripts can be placed.
An original tray 10a and an original placed on the original tray 10a
Separate manuscripts one by one from bundle 80 and contact glass
Equipped with a separation / feeding roller group for conveying toward 1a
The paper supply unit 10 and the contact glass 1
The original conveyed toward a is placed on the contact glass 1a.
Transport and stop at the original reading position, and
Image reading unit of copier 1 disposed below door 1a
(Known exposure lamp, mirror, lens, CCD, etc.)
Conveys the scanned original from the contact glass 1a.
Conveying unit 2 with conveying roller group and conveying belt
0 and the original on the contact glass 1a by the transport unit 20
Copy the original delivered from the scanning position according to the copy mode
The paper ejection tray 30a or the document tray protruding to the side of the
Any of the paper discharge trays 30b arranged below the a 10a
A paper discharge unit 3 having a reverse and paper discharge roller group for discharging paper to one side
0. Each component will be described in detail.
Reference numeral 10 denotes a call roller 10b, a paper feed roller 10c, and a reverse roller.
Roller 10d, pullout drive roller 10e, pullout
The moving roller 10f and the document detection sensors 40a and 40b
Has been established. These call rollers 10b and paper feed rollers 10
c, reverse roller 10d, pull-out drive roller 10e
The sheet feeding motor 1 is driven by a sheet feeding motor 10m.
0m via a drive system such as a gear mechanism.
You. Then, as shown in the basic configuration of FIG.
10m is driven by a control signal from the controller 50
The controller 50 is connected to the copier 1
When a paper feed start signal is input from the
m is driven forward and reverse. When the feed motor 10m is driven to rotate forward,
The delivery roller 10b rotates clockwise to move the
While the upper document is fed,
0c and the reverse roller 10d are rotated clockwise to
Only the top document is separated from the bundle 80. This separation
The original is placed in a pull-out drive roller that rotates counterclockwise.
10e and the pull-out driven roller 10f that rotates with it
Between the feed roller 10c and the reverse roller 10d
Drawn out of the container and transported toward the contact glass 1a.
You. The leading edge of the document is a pull-out drive roller 10e and a pull-out
Document detection sensor disposed downstream of the driven roller 10f
When the controller 50 detects the document,
Paper feed motor based on an output signal from detection sensor 40b
10m is driven in reverse rotation. At this time, the feed motor 10m
Roller 10b, paper feed roller 10c, reverse roller 1
0d and the drive interposed between the pull-out drive roller 10e
The call roller 10b and the paper feed roller 10c are stopped by the dynamic system.
And the pull-out driving roller 10e continues in the counterclockwise direction.
While rotating, reverse roller 10d is connected clockwise.
Continued rotation will cause subsequent documents to be fed
Prevents 10c and reverse roller 10d from entering the nip
So that they are not separated. Meanwhile, separate first,
The conveyed original is pulled out by a pull-out driving roller 10e and a pull-out
The paper is fed from the paper feeding unit 10 to the transporting unit 20 by the out driven roller 10f.
Transported to The transport section 20 includes a transport belt 20a,
Conveying belt drive provided at both ends of the conveying belt 20a
Roller 20b, conveyor belt driven roller 20c, and conveyor bell
The conveyor belt 20a is provided inside the
From a plurality of pressure rollers 20c for pressing the glass
It is configured. The transport belt drive roller 20b is
20 m
The feed motor 20m is described above by the document detection sensor 40b.
When the leading edge of the document is detected as described above, the controller 5
By performing forward rotation driving based on the signal from 0, the transport
Drives the conveyor belt 20a via the belt drive roller 20b
So that the original is conveyed onto the contact glass 1a.
ing. The original conveyed from the paper supply unit 10 is a conveying bell.
20a, is transferred onto the contact glass 1a by the
The trailing edge of the document is detected by the document detection sensor 40b
And the controller 50 controls the transfer motor from this detection time.
20m rotation pulse is counted and the rotation pulse reaches the specified value
Then, the driving of the conveyor belt driving roller 20b is stopped.
The original is conveyed by stopping the transport belt 20a.
The document is stopped at the document reading position on the tact glass 1a. Soshi
The document stops at the document reading position on the contact glass 1a
The document is read and exposed by the copying machine 1.
Be done. When this reading and exposure is completed,
A signal is input from the copying machine 1 to the
20m is driven to rotate forward, and the original is transported by the transport belt 20a.
From the contact glass 1a to the paper discharge unit 30. On the other hand, the controller 50 is a document detection sensor.
At the time when the trailing edge of the original is detected by 40b, or
When the feed motor 10m and transport motor 20m stop
Then, the paper feed motor 10m is driven again, and the following original (next
Document) is separated and fed as described above. The leading edge of the next original is
Downstream of the paper roller 10c and the reverse roller 10b (pull-out
Drive roller 10e and pull-out driven roller 10f
(Or upstream of the document detection sensor 40b).
Paper feed motor from the time point detected by output sensor 40a
10m rotation pulse is counted and the rotation pulse reaches the specified value
When the call is made, the calling roller 10b, the paper feeding roller 10c, and the
Stop the driving of the bar rollers 10b and perform the advance operation of the original.
Ends, stops the next original at a predetermined position in paper feed unit 10, and waits
Let it. The paper discharge section 30 includes a reversing drive roller 30c and a paper discharge
Driven roller 30d, reversing guide roller 30e, reversing driven roller
30f, the first switching claw 30g, the second switching claw 30h,
Moving roller 30i, discharge driven roller 30j, reversing sensor 40c
And 40d, the inversion drive roller 30c, the inversion gear
The id roller 30e and the sheet discharge drive roller 30f
0 m. The controller 50 conveys a one-sided original.
In single-sided mode, the first switching claw 30g is
Where the paper 1a communicates with the first paper discharge tray 30a (home
Position) to read and scan the original.
Drive the transport motor 20m after the
The discharge motor 30m is driven, and the reverse drive roller 30c and
The document nipped by the discharge driven roller 30d is
The sheet is ejected linearly to a 30a. On the other hand, the controller 5
0 is the first switching claw 30g when the duplex mode is designated.
From home position to contact glass 1a
A countermeasure via the driving roller 30c and the reversing guide roller 30e
By moving the transfer path to a position where
After reading of one side of the manuscript and the end of the exposure, the transport motor 20m
At the same time as driving the paper ejection motor 30m
To the reverse path. In addition, the controller 50
In the duplex mode in which the original is conveyed, the second switching claw 30h
The return path from the inversion path to the contact glass 1a.
To wait at the communicating position (home position)
Original, the original is turned upside down and the reverse drive roller 3
0c and the reverse driven roller 30f
Returned to lath 1a. In this inversion operation, the inversion
The leading edge of the document is detected by a reversing sensor 40d provided on the road.
Is detected, the controller 50 moves the transport motor 20m.
To rotate the transport belt 16 in the reverse direction.
The rotation pulse of the transport motor 20m reaches a predetermined value.
When the original is placed at the original reading position on the contact glass 1a
Judge that it has been transported and stop the transport motor 20m
You. Then, at the original reading position,
When reading and exposure are completed, the controller 50
A signal is input from the copying machine 1 to drive the transport motor 20m forward.
Moving and contact by the first switching claw 30g.
The second switching is performed while communicating the glass 1a with the reversing path.
The pawl 30h connects the reversing path to the paper discharge tray 30b.
And reverse the original delivered from the contact glass 1a
Drive roller 30c, reverse driven roller 30d, paper discharge drive roller
30i and the output tray 3 via the output driven roller 30j.
0b. In the image processing apparatus having such a configuration,
Separation of paper feed unit 10, paper feed roller group (10b to 10f)
Corresponds to the document conveying means, and the document detection sensors 40a and 40
0b correspond to the first and second document detection means,
This configuration is the same as that of an existing image processing apparatus to which the present invention is applied.
It is. Next, the self-application applied to the image processing apparatus described above.
Pulse count operation and document size
The constant processing will be described. [0027]FIG.Pulse counting of automatic document feeder
6 is a flowchart illustrating a reset operation. The pulse cow
Event operation is performed in the pulse counter 50b.
Or may be controlled by the controller 50
It may be something. Document bundle 80 is on document tray 10a
And the original is transported from the operation panel to start copying, etc.
When the controller 50 receives the start signal, the sheet feeding motor 1
0m and drive the pulse counter by the following procedure.
Start operation. Detection of the length of the original in the transport direction has been completed.
The size flag to determine whether or not
Is set to "1" if size detection has been completed, and size detection has not been completed.
Otherwise, it is set to “0”. The count operation starts
Count flag to determine whether
If the operation has started, the count operation ends.
If so, it is set to "0". New document reading operation
When instructing, the size flag is set to “0” and the count flag
The lag is set to “0”. When document conveyance is started, these flags
It is determined whether or not is reset ("0")
(S1, S2). Next, the call roller 10b and the paper feed roller 1
Original document separated and conveyed by 0c and reverse roller 10d
Of document is upstream (or upstream sensor) 40a.
Is detected and turned on (S3), the pulse counter
50b count value (P_CNT) Is cleared (= 0) and
The run flag is set to "1" (S4), and the feed motor
The output from the pulse generator 50a is synchronized with the operation of 10m.
The counting of the pulse signals to be started is started (S5). Manuscripts in order
The document is conveyed in the direction of the conveyance section 20 and is a downstream document detection sensor.
(Downstream sensor) The trailing edge of the document is detected by 40b and OF
In the F state (S6), the count flag is reset.
("0") to stop the counting operation of the pulse counter 50b.
Stop (S7). The count value thus counted
(P_CNT), The upstream sensor 40a and the
Of pulses corresponding to the installation distance between the sensor and the downstream sensor 40b
(P₀) Is subtracted, and the length of the document in the transport direction is
Number of pulses equivalent to the length (number of pulses equivalent to the length: P_L= P_CNT
-P ₀) Is calculated (S8), and the size flag is calculated.
Is set to “1” and the pulse count operation is completed (S
9). FIG.Claim 1Automatic document feeder
Document size executed by original document size determination unit 50c
It is a flowchart which shows a determination process. First, the manuscript size
In the size determination process, the size flag is set to "1".
It is determined whether or not there is (S11). Mentioned above
The number of pulses equivalent to the length (PL) is increased by the pulse count operation.
Is calculated and the size flag is set to "1".
The original size is determined by the next comparison process.
Is performed. Specifically, preset for each standard paper size
Number of size determination pulses (PS) and number of length equivalent pulses
(PL) to determine the corresponding size.
So, for example, the size of B5 size paper is 257 length x width
182mm, so compare B5 size horizontal dimension 182mm
Set 66 pulses as the number of pulses to be determined, and
Since the size of the size is 297 × 210 mm,
Set 78 pulses horizontally and 112 pulses vertically A4,
The size of the B4 plate size is 354 length x 250 mm width.
Therefore, in B4 vertical size is 136 pulses.
The number of constant pulses (PS) is set in advance. And pal
Number of pulses equivalent to the length obtained by the count operation (P
L) is the number of size determination pulses (PS = 66, 78, 11)
2, 136) and the number of pulses equivalent to the length (PL)
Is less than 66 (S12), a B5 size document is
Judge and set the size data flag B5F to "1".
(S17) The B5 size is designated as the copy sheet.
Next, when the length equivalent pulse number (PL) is less than 78 (S
13) is determined to be A4 size horizontal size and flag A4YF
Is set to "1" (S18), and the A4 size landscape paper is
When the number of pulses equivalent to the length (PL) is less than 112
In (S14), the size is determined to be the A4 size and the flag A4T is determined.
F is set to "1" (S19), and A4 size portrait paper is used.
Specify, and the number of pulses equivalent to the length (PL) is less than 136
In the case of (S15), the size is determined to be the B4 size and the flag is set.
B4F is set to "1" (S20), and B4 size
Specify paper. Number of length equivalent pulses (PL) is 136 or more
In the case of (S15), the size data flag A3
F is set to "1" (S16), and A3 size paper is
specify. Such a series of pulse counting operations and
According to the document size determination process, the upstream sensor 40a
Detecting the leading edge of the document and the trailing edge of the document by downstream 40b
Depending on the original and the downstream sensor
Different points (leading and trailing)
Compared to the case of detecting the size with a single sensor
Of count values due to slippage or deflection of originals
And correct errors in document size.
Can be performed. Next,A different form than the one described aboveAutomatic
The pulse count operation of the document feeder is shown in the flow chart of FIG.
This will be described with reference to a chart.The pulse count described above
As well asWhen document transport starts, the size flag and
And whether the count flag is reset ("0")
Is determined (S21, S22). Next is the original bundle 80
The leading edge of the document separated and conveyed from the sensor is detected by the downstream sensor 40b
Is turned on (S23), the pulse counter 50
clears (= 0) the count value (PCNT) of b
The print flag is set to "1" (S24), and the feed motor 1
Output from the pulse generator 50a in synchronization with the 0 m operation.
The counting of the pulse signals to be started is started (S25). Manuscripts in order
It is conveyed in the direction of the conveyance unit 20 and is detected by the upstream sensor 40a.
When the trailing edge of the document is detected and turned off (S26),
Resets the count flag ("0") and sets the pulse counter
The counting operation of 50b is stopped (S27). Like this
The count value (PCNT) counted in advance
Installation distance between the upstream sensor 40a and the downstream sensor 40b
A correction process for adding the number of pulses (P0) corresponding to the separation is performed.
And calculates the number of pulses equivalent to the length (PL = PCNT + P0)
(S28) and set the size flag to "1".
To end the pulse counting operation (S29). Such a series of pulse counting operations and
According to the above-described document size determination process (FIG. 4),
Sensor 40b and the upstream sensor 40a
Counting operation of pulse counter 50b by detecting the trailing edge of document
Is controlled, the time required for counting the number of pulses isthe first
ToIt can be shorter than the counting method shown.
Error due to error or slippage or deflection of the original
Appropriate document size that can reduce fluctuations and errors
Can be determined. Next,Claim 1Of the automatic document feeder according to
6 and 7 show the pulse count operation.
The explanation will be made with reference to the chart. The feature of the present invention is two sensors
Detects the leading and trailing edges of the document individually.
There are two types of count values (PCNT) by the counter 50b
It is something that can be obtained. The upstream cell 40a and the downstream cell 40a
The same pulse count operation is performed independently with the sensor 40b.
Therefore, the description of the same processing steps is omitted. First, the pulse count on the upstream sensor 40a side
To explain the operation,Mentioned abovePulse count operation
Like the operation, when the document conveyance is started, the upstream sensor 40a
To determine whether the length in the transport direction has been detected.
The stream size flag and count flag are reset ("0")
It is determined whether or not it has been performed (S31, S32). Next
The leading edge of the document separated and conveyed from the document bundle 80 is
When it is detected by the sensor 40a and turned on (S33), the
Clear the count value (PCNT1) of the loose counter 50b.
(= 0), and sets the count flag to "1" (S3
4), a pulse generator in synchronization with the operation of the paper feeding motor 10m
The counting of the pulse signal output from 50a is started (S
35). Documents are sequentially conveyed in the direction of the conveyance unit 20 and are moved upstream.
The sensor 40a detects the trailing edge of the document and turns off the sensor.
At this time (S36), the count flag is reset ("0").
To stop the counting operation of the pulse counter 50b (S3
7). Next, the count value (PC
NT1) Read completion flag to determine completion of reading
Is set to "1" (S38), and the upstream size flag is set.
Set the lag to "1" and end the pulse count operation
(S39). Also, the pulse counter on the downstream sensor 40b side
The downstream size flag and count flag
It is determined whether the reset has been reset ("0")
Later (S41, S42), the leading edge of the document is detected by the downstream sensor 40b.
Is detected and turned on (S43), the pulse count
Count value (P_CNT2) Is cleared (= 0),
The count flag is set to "1" (S44), and the pulse
Signal counting is started (S45). Documents are sequentially transported by transport unit 2
The document is conveyed in the zero direction, and is placed behind the document by the downstream sensor 40b.
When the end is detected and turned off (S46), counting is performed.
The flag is reset ("0") to stop the counting operation (S
47) Set the downstream size flag to “1” and
(S48), the two counted values (P_CNT1, P
_CNT2), And if they are the same, one of the count values
And if they are different, average them to obtain the number of pulses equivalent to the length.
[P_L= (P_CNT1+ P_CNT2) / 2]
(S49), the size flag is set to “1” and the
The loose count operation ends (S50). Such a series of pulse counting operations and
According to the document size determination process, the upstream and downstream
The sensor detects the leading and trailing edges of the document individually and counts the number of pulses.
Counting, two types of count values (P_CNT1,
P_CNT2), And these two values are compared and averaged.
Count value (P_L) To determine the original size
Can be performed, so that one document detection
Number of pulses equivalent to the length compared to detection with a sensor
(P_L) Can be calculated more accurately, and
Can suppress count value variations and errors due to
it can. The automatic document feeder of the present invention is applicable.
A copying machine has been described as an example of a functional image processing device.
Needless to say, the present invention is not limited to this. Ma
Further, the pulse count operation, which is a feature of the present invention, is controlled.
The upstream and downstream document detection sensors are connected to the paper feeder of the copier.
The arrangement configuration is shown, but in a series of document conveyance operations
The process that needs to know the document size, for example, image processing
It only needs to be placed in the transport path up to the
It is desirable to use an existing sensor in the image processing apparatus. [0039] According to the first aspect of the present invention, the conventional device
The two upstream and downstream sources that were also installed in
Start counting of the pulse counter by the article detection sensor and
The end operation is controlled, and the original is detected by the two sensors.
The document size is determined based on the count value within the specified period.
Document size to directly detect the document size.
Need new configuration such as id and potentiometer
Without detecting the original with two sensors
Correct the count value counted by the pulse counter
Processing to calculate the pulse value equivalent to the document length.
If the count value is
Judgment of the original size appropriately while suppressing fluctuations and errors
Can be.More specifically, it is provided in the document conveying path.
The upstream and downstream document detection sensors are independently
Compare these two counts to count the number of
Equivalent to the original transport length by performing the averaging process
The number of pulses has been optimized and slips and deflections during document transport
To reduce the effects of count value variations and errors
Can be. Also,Other embodimentsAccording to the document transport
The document is detected by the document detection sensor located on the upstream side of the road.
Starts pulse counting by detecting the tip and locates downstream
The trailing edge of the original is detected by the original
Count value obtained by stopping lus count
From the number of pulses corresponding to the original length in the original transport direction.
It is possible to calculate and determine the document size.
Slip or skew during document transport when using one sensor
The variation and error of the count value due to
it can. Further,Other embodimentsAccording to the original transport
The original is detected by an original detection sensor located downstream of the paper path.
Starts pulse counting by detecting the leading edge of the document and distributes it upstream.
The document trailing edge is detected by the placed document detection sensor.
To stop pulse counting and count the number of pulses,
The period counted by the Luz counter can be shortened.
Error due to counting of pulse signals and slippage during document transport
To suppress variations and errors in count values due to loops and deflections.
Can be [0042]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a basic configuration of an automatic document feeder according to the present invention. FIG. 2 is a diagram showing a schematic configuration of an image processing apparatus to which the automatic document feeder of the present invention can be applied. FIG. 3 shows a pulse counting operation of the automatic document feeder .
It is a 1st flowchart. FIG. 4 is a flowchart illustrating a document size determination process of the automatic document feeder according to the present invention. Figure 5 shows a pulse counting operation of automatic document feeder
It is a 2nd flowchart. FIG. 6 is a flowchart showing a pulse counting operation of an upstream document detection sensor of the automatic document feeder according to the first embodiment. FIG. 7 is a flowchart showing a pulse counting operation of a downstream document detection sensor of the automatic document feeder according to the first embodiment. [Description of Signs] 1 Copier (image processing apparatus) 1a Contact glass 10 Paper feed unit 10a Document tray (document mounting table) 10b Recall roller 10c Paper feed roller 10d Reverse roller 10e Pull-out drive roller 10f Pull-out driven roller 10m Paper feed motor (Drive unit) 20 Conveying unit 20a Conveyor belt 20b Conveyor belt drive roller 20c Conveyor belt driven roller 20d Pressurizing roller 20m Conveyor motor (drive unit) 30 Paper discharge units 30a, 30b Discharge tray 30m Paper discharge motor (drive unit) 40a 40b Document detection sensor (first and second document detection means) 50 Controller (control means) 50a Pulse generator (pulse generation means) 50b Pulse counter (pulse counting means) 50c Document size determination section (document size determination means) 60 operation unit 70 interface 80 manuscript 100 automatic document feeder

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-47910 (JP, A) JP-A-9-226982 (JP, A) JP-A-6-230629 (JP, A) JP-A-4- 333451 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/00 107 G03G 21/14 G03G 21/00 370-512

Claims (1)

(57) [Claim 1] A document transport means for transporting a document on a predetermined transport path, and a document provided at a predetermined position in the transport path and transported by the document transport means. A first document detecting means for detecting, a second document detecting means provided at a distance from the first document detecting means in the transport path behind the first document detecting means in the transport direction, and a driving means for driving the document transport means. Pulse generating means for outputting a predetermined pulse signal in synchronization with the operation of the driving means, and counting the pulse signals output from the pulse generating means based on the detection signals from the first and second document detecting means. Pulse number counting means, a document size determination means for performing a predetermined correction process on the number of pulses counted by the pulse number counting means to determine the size of the document, and counting start and end operations of the pulse number counting means Controls, and a control means for controlling the operation processing according to the pulse number correction processing of the document size determination means,
The control means may be configured such that the pulse number counting means determines that the first
Counting when the leading edge of the original is detected by the original detecting means.
Start counting and count when the trailing edge of the original is detected.
Control to end and obtain the first pulse number
Then, the leading edge of the document is detected by the second document detecting means.
Counting starts when the document is output, and the trailing edge of the original is detected.
At the point when the counting is completed to obtain the second pulse number.
And the document size determining means controls the number of pulses.
The first and second pulse numbers counted by the number means are averaged.
Automatic manuscript characterized by being controlled to perform leveling processing
Transport device.