JPH0980827A - Automatic document feeding apparatus and method - Google Patents

Abstract

(57) Abstract: When a document is conveyed, the size of the document is checked by a paper feed sensor S2. Then, when the detected document size is less than B4, the document is conveyed by a predetermined amount, the document is set on the platen, and then the sequence of "reversal 1" is performed. On the other hand, if the detected document size is B
When it is 4 or more, the reversing motor is driven without stopping the belt motor, and the sequence goes to the "reversing 2" sequence. SOLUTION: The size of the original is detected when the original is fed,
By switching at least two inversion paths according to the original size, the inversion time can be shortened for each original size, and the original inversion time can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder and an automatic document feeder for reversing the front and back of a document placed on a document placing tray according to the reading surface of the document. It relates to the feeding method.

[0002]

2. Description of the Related Art As an automatic document feeder of this type which has been conventionally known, there is a device mounted on a platen glass of a copying machine.

Such a conventional automatic document feeder has only one reversing path for reversing the front and back of a document.

Therefore, when reversing an original, the original is always stopped once on the platen and then the original is inverted regardless of the size of the original. As a result, the reversal time due to the stop operation has become long.

[0005]

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned problems, an object of the present invention is to provide an automatic document feeder and method for reducing the document reversal time.

[0006]

In order to achieve such an object, a first embodiment of the present invention, when a document placed on a document placing tray is conveyed, depending on the reading surface of the document,
In an automatic document feeder that reverses the front and back of the original,
A plurality of document reversing means for inverting the front and back of the document, a detecting means for detecting the size of the document, and a selecting means for selecting one of the document reversing means in response to the output of the detecting means. It is equipped with and.

In the second aspect of the present invention, the size of the original document is detected when the original document placed on the original document tray is conveyed, and the original document is detected in response to the result of the detection process. One of a plurality of document reversing paths provided for reversing the front side and the back side is used by switching.

[0008]

According to the first and second embodiments of the present invention, the size of a document is detected when the document is fed, and at least two reversing paths are switched according to the size of the document. The inversion time can be shortened by making the inversion time shortest for each original size.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the structure of an automatic document feeder (hereinafter referred to as ADF) to which the present invention is applied. In the figure, 1 is a document stacking tray on which documents S are stacked and set. The tray 1 is for placing a document, and is arranged so as to be lower on the document feeding side and inclined downward as it goes in the document feeding direction. As a result, the documents to be fed are uniformly stacked in the feeding direction.

Reference numeral 3 denotes a half-moon roller, which is rotated in a direction of an arrow and sends out a document to a downstream separating section.
When there is no document in the document, it is controlled so that the cutout portion faces upward and is stopped.

Reference numeral 19 denotes a recycle lever, which is driven by a recycle motor 20a at the start of document feeding and placed on the uppermost surface of the document to distinguish the last fed document from the copied document.

A feeding roller 6 is rotated in the direction of the arrow to feed the original fed from the tray 1. Further, 7 and 8 are separating rollers, and by rotating the separating belt 9 in the direction of the arrow, one of the lowermost originals among the originals stacked on the tray 1 is fed between the separating belt 9 and the feeding roller 6. To separate. The feeding roller 6 and the separation belts 7 and 8 form a separation feeding unit.

The original sent from the separating / feeding section is sandwiched between the feed rollers 11 and 12 which are driven by the sheet feeding motor 10a and pressed against each other, and the platen glass 15 is rotated by the rotation of the rollers in the direction of the arrow. Sent up.

Further, the paper feed motor 10a also serves to drive the first discharge roller 13a and the second discharge roller 13b.

The entire belt 18 on the platen glass 15
Is an endless belt having a width large enough to cover the entire surface of the sheet original, and the surface has a sufficient friction coefficient so that the original can be slid on the platen glass 15 by a frictional force and conveyed in the direction of the arrow. It is hung on the driving roller 16 and the turn roller 17, and the whole belt 18 and the driving roller 1
6 and 6 are configured so as not to slip.

The first discharge roller 13a is the feed roller 12
The originals discharged from the platen glass 15 by the movement of the entire surface belt 18 are rotated in the direction of the arrow and are nipped and conveyed. The original document is nipped by the second ejection roller 13b and ejected to the original document tray 1.

The flapper 30 is the flapper shown in FIG.
It is driven by a solenoid to switch between the reverse path and the paper discharge path. The reversing roller 31 is in pressure contact with the feed roller 32 and is driven by the reversing motor 33a.

FIG. 2 is a control block diagram of the ADF shown in FIG. FIG. 3 is a control block diagram of the copying machine connected to the ADF of FIG.

As shown in FIG. 2, AD according to this embodiment is used.
F is mainly composed of a one-chip microcomputer (CPU), and further exchanges signals with a controller (CPU) of the copying apparatus shown in FIG. 3 and a communication interface circuit (not shown). Various controls are performed while performing.

Each input port of the CPU shown in FIG.
The document detection sensor S1 (24 in FIG. 1) provided in the downstream direction of the tray 1, the paper feed sensor S2 (22 in FIG. 1) provided on the document transport path, and the paper discharge sensor S3 (FIG. 1).
21), the reversing sensor S4 (23 in FIG. 1), the belt clock sensor 14d, the paper discharge clock sensor 10c, the reversing clock sensor 33c, and the recycle lever reference position detection sensor 20c.

On the other hand, the operation signals of the separation motor, the belt motor, the electromagnetic brake, the paper feed motor, and the recycle motor are output to the respective output ports of the CPU included in the ADF, and the respective output loads are output via the respective drivers. Control.

From the controller of the copying machine shown in FIG. 3, a document feed signal, a document discharge signal and a document exchange signal are input to the CPU of the ADF. Furthermore, A
From the DF to the copying machine, C via each output port
An OPY request signal, a document detection signal, and a document size signal are output.

Drive signals for the flapper solenoid 100 and the reversing motor 33a are output from the remaining output ports of the CPU included in the ADF.

The CPU of the ADF has a ROM that stores a control program, a RAM as a work area during calculation, an EEPROM that is a non-volatile memory, an A / D converter for reading a voltage value, and a voltage varying means. Is connected to the D / A converter.

FIG. 4 is a flowchart showing the control procedure of the ADF according to this embodiment. ADF according to this embodiment
When receiving a document feed signal from the copying apparatus, starts document feeding (step S1).

When the document is conveyed, the size of the document is checked by the paper feed sensor S2 (step S2). Then, when the detected document size is less than B4 (step S3: NO), the document is conveyed by a predetermined amount and is set on the platen (step S4: YES), and then "reversal 1" (step 1). The sequence moves to S5).

On the other hand, when the size of the detected document is B4 or more (step S3: YES), the reversing motor 33a is driven without stopping the belt motor 14a, and the "reversing 2" (step S6) sequence is performed. Move on to.

After confirming that the original has been set at the reference position, the copying apparatus shifts to the image forming operation on the back surface of the original, and immediately after that, transmits an original exchange signal to the ADF (step S7).

Next, the ADF is inverted 1 (step S8).
The document is inverted again according to the sequence of.

After confirming that the original has been set at the reference position, the copying apparatus moves to an image forming operation on the surface of the original, and immediately after that, transmits an original exchange signal to the ADF (step S9). The ADF thereby discharges the original on the platen (step S10) and feeds the next original.

Then, this operation is performed by feeding all originals.
The process is continued until image formation is performed (step S11).

FIG. 5 shows a flow chart of the "size detection" routine shown in step S2 of FIG. First, when the leading edge of the document is detected by the paper feed sensor S2 (step S
21), the movement amount of the belt clock disc 14c attached to the shaft of the belt motor 14a is measured by the belt clock sensor 1
4d starts detection (starts counting: step S22).

Next, when the trailing edge of the original is detected by the paper feed sensor S2 (step S23), the started count is stopped (step S24), and the original is B4 size according to the number of pulses in that period (step S25). It is determined whether or not the above (steps S26 and S27).

FIG. 6 shows a flow chart of the "reverse 1" routine shown in FIG. First, when it is determined from the output of the size detection routine that the document size is smaller than B4, the flapper 30 switches the paper discharge path to the reverse path, the belt motor 14a is reversely rotated, and the feed roller 12 performs the reverse operation. I do. Then, after the paper discharge sensor S3 detects the edge of the document (step S31), the document is conveyed by a predetermined amount (step S32), and the paper feed sensor S2 waits for turning on (step S33). The normal rotation of the belt motor 14a is started (step S34), and the sheet feeding sensor S2 is turned off (step S3).
5) After the document is conveyed by a predetermined amount (step S3)
6) The belt motor 14a is stopped and the document is placed on the platen (step S37).

FIG. 7 shows a flow chart of the "reverse 2" routine shown in FIG. First, when it is determined from the output of the size detection routine that the document size is B4 or more, the reversing roller 31 performs the reversing operation. Then, after the leading edge of the document is detected by the reversing sensor S4 (step S41), the rotation of the belt motor is switched in the paper discharge path direction, and the reversing motor 33a conveys the document by a predetermined amount (step S42), and then, the reversing Motor S
When the trailing edge of the original is detected by step 4 (step S43), the original is conveyed by a predetermined amount (step S44), and the original is set at the platen reference position (step S45).

[0037]

As described above, according to the present invention, the size of a document is detected at the time of feeding the document, and at least two reversing paths are switched according to the size of the document, so that the size of each document can be minimized. Set the reversal time,
The document reversal time can be shortened.

[Brief description of drawings]

FIG. 1 is an automatic document feeder (ADF) to which the present invention is applied.
FIG.

FIG. 2 is a control block diagram of an ADF according to this embodiment.

FIG. 3 is a control block diagram of a copying machine connected to the ADF shown in FIG.

FIG. 4 is a flowchart showing a control procedure of this embodiment.

FIG. 5 is a flowchart showing a size detection routine.

FIG. 6 is a flowchart showing an inversion 1 routine.

FIG. 7 is a flowchart showing an inversion 2 routine.

[Explanation of symbols]

 1 Document Loading Tray 2 Document Stopper 3 Half Moon Roller 4 Document Holding Plate 5 Separation Motor 6 Feed Roller 7, 8 Separation Roller 9 Separation Belt 10a Paper Feed Motor 10b Paper Feed Clock Disc 10c Paper Ejection (Paper) Clock Sensor 11, 12 Feed Roller 13a Discharge First Roller 13b Discharge Second Roller 14a Belt Motor 14b Brake 14c Belt Clock Disc 14d Belt Clock Sensor 15 Platen Glass 16 Drive Roller 17 Turn Roller 18 Full Belt 19 Recycle Lever 20a Recycle Motor 20b Recycle Motor Encoder 20c Recycle lever reference position detection sensor 21 Paper discharge sensor S3 22 Paper feed sensor S2 23 Inversion sensor S4 24 Original detection sensor S1 30 Flapper 31 Inversion roller 32 Inversion feed roller 33a Reversed Inversion motor 33b Inversion motor encoder 33c Inversion clock sensor

Claims (2)

[Claims] 1. An automatic document feeder for reversing the front and back of a document according to the reading surface of the document when the document placed on the document tray is conveyed, and the document is reversed. A plurality of original reversing means, a detecting means for detecting the size of the original, and a selecting means for selecting one of the original reversing means in response to the output of the detecting means. Automatic document feeder. 2. When the original placed on the original placing tray is conveyed, the size of the original is detected, and in response to the result of the detection process, the front and back of the original are reversed. The automatic document feeding method is characterized in that any one of a plurality of original reversing paths is switched and used.