JPH11246101A - Automatic document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily arrange a succeeding document on the nonreading surface side of a preceding document by arranging the step different part forming a space into which the tip of the succeeding document enters, between the carrying surface of a carrying passage to introduce the document and the rear end of the preceding docu ment in a automatic document feeder to successively discharge the document to a discharge tray by reversing the obverse/reverse after reading the document. SOLUTION: When a document positioned in the lowest position of a paper feeding tray and a document positioned in the next place are successively fed at prescribed intervals, first of all, a preceding document is carried by a carrier belt means. Next, a pad member 23 is pushed down, the carrying directional rear end side of the preceding document is sandwiched by cooperating with a platen 2, and the carrying directional rear end part of the preceding document separates from the upper surface 24a by a step difference with the surface of the platen 2 of the butting surface 24b. While, when a succeeding document is carried toward the platen 2, the carrying directional tip of the succeeding document enters the carrying directional rear end of the preceding document to complete overlapping of the document. The document are carried on the platen 2 still in this state to be read by a recording information reader.

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 more particularly to an automatic document feeder, in which two originals sequentially fed from a paper feed tray are aligned in parallel on the upstream side of a platen and are brought to a reading position of the platen. The present invention relates to an automatic document feeder having a feed mode in which two documents read and read are inverted and sequentially discharged to a discharge tray.

[0002]

2. Description of the Related Art Conventionally, for example, in a copying machine, a plurality of documents placed on a paper feed tray are fed, conveyed onto a platen, and discharged at the platen reading position. 2. Description of the Related Art An automatic document feeder that discharges a document to a tray is known.

[0003] In such an automatic document feeder,
Due to the space required for the copier body, at least a part of the paper feed tray and the paper output tray are overlapped or shared, and a plurality of documents placed on the paper feed tray are facing upward with respect to the reading surface. The document is read after it is turned downward on the transport path from the paper feed tray to the platen, and then turned up again on the paper discharge path from the platen to the paper output tray, so that the order of the originals after discharge is placed. It does not reverse the position.

On the other hand, such an automatic document feeder includes:
Two sheets of the plurality of documents placed on the paper feed tray are sequentially fed as a set, and the two documents are aligned in parallel on the upstream side of the platen. 2. Description of the Related Art There is known an automatic document feeder having a feed mode in which two read documents are inverted and sequentially discharged to a discharge tray.

[0005]

By the way, in the automatic document feeder configured as described above, of the documents in the set, a document to be transported first (previous document) and a document to be transported later. If there is a gap between adjacent edges of a document (next document), the information recorded at the leading edge of the preceding document in the transport direction or the trailing edge of the next document in the transport direction will not be read. It may not be possible.

Therefore, it is conceivable that all recorded information on each original can be read by overlapping the leading end of the preceding original in the transport direction with the rear end of the next original in the transport direction.

However, when the leading end of the preceding original in the conveying direction and the trailing end of the next original in the conveying direction are overlapped, it is difficult to overlap the next original when the preceding original is at the reading position on the platen. is there. Also, in this case,
Since the two originals after scanning are ejected at the same time, taking into account that the above-described ejection order of the originals after ejection does not reverse to the original placement, the superimposition of the preceding original and the next original is considered. However, it is difficult to position the next original on the non-reading surface side (back side) of the preceding original.

Therefore, the superposition is realized by starting the feeding of the next original just before the feeding of the preceding original from the paper feeding tray is completed, or the conveying speed of the conveying rollers on the conveying path is varied. It is conceivable that the next document can catch up with the preceding document.

However, in order to start feeding the next document immediately before the feeding of the preceding document from the paper feed tray is completed, it is necessary to reduce the size of the document in order to control the timing of feeding the preceding document and the next document. Not only is it difficult to control the corresponding time and set the detection position of the preceding document conveyance position detection sensor, but also there are problems such as the inability to register the next document.

Further, when the superposition is realized before the original is conveyed to the platen by, for example, changing the conveyance speed of the conveyance roller on the conveyance path, the preceding original is not necessarily conveyed like the superposition on the platen. Is not always located on the non-reading side of the document.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an automatic document feeder which can easily and inexpensively position the next document on the non-reading surface side of the preceding document. I do.

[0012]

In order to achieve the object, two originals sequentially fed from a paper feed tray are aligned in parallel, sent to a platen, and read at a reading position of the platen. In an automatic document feeder having a feed mode in which sheets of a document are turned upside down and sequentially discharged to a discharge tray, between the conveyance surface of a conveyance path for guiding a document from a paper feed tray onto a platen and a rear end of the preceding document. The gist is that a step is formed to form a space into which the leading end of the next original enters, and the next original is superimposed below the trailing end of the previous original and supplied onto the platen.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of an automatic document feeder according to the present invention will be described with reference to the drawings, applied to an automatic document feeder for a copying machine.

In FIG. 6, 1 is a copying machine main body, 2 is a platen provided in the copying machine main body 1, and 3 is an automatic document feeder.

The automatic document feeder 3 includes a paper feed tray 5 mounted on the main body cover 4 and on which a document to be read is placed.
A paper feed unit 6 provided near a paper feed port 4 a provided in the main body cover 4 and sequentially feeding two sets of originals placed on a paper feed tray 5 as a set; A transport unit 7 for transporting the fed document toward the platen 2;
Is carried over to the reading position on the platen 2 while the document is conveyed to the reading position (not shown) provided in the copying machine 1. Belt means 8,
A parallel section 9 provided at the end of the transport section 7 located on the upstream side in the transport direction with respect to the transport belt means 8, a discharge section 10 continuous from the end of the transport belt means 8, and the main body cover 4 are formed integrally. And a discharge tray 11 on which the documents discharged from the discharge unit 10 are sequentially stacked.

The paper supply unit 6 includes a substantially half-moon-shaped separating roller 12 for separating a plurality of documents placed on the paper supply tray 5,
A paper feed roller 13 for feeding the lowermost document to the transport unit 7;

The transport section 7 includes a transport path 14 having a substantially U-shaped cross section for reversing the original fed from the paper feed roller 13, and a sensor 15 for detecting the original fed to the transport path 14.
And a registration roller 16 that is driven based on the detection result of the sensor 15 and registers a document on the transport path 14.

The transport belt means 8 includes an endless belt 17 which is wide in a direction orthogonal to the document transport direction, and a plurality of rollers 18 for rotating the endless belt 17.

The parallel section 9 includes a document stacking section 19 and document pressing means 20 located above the platen 2 near the start end in the document transport direction. The document pressing means 20 is
A driving source 21 such as a motor or a solenoid, an arm member 22 that rotates with the driving of the driving source 21, and an arm member 22.
And a pad member 23 slidably provided at the tip end of the transfer belt means 8.
Is forcedly stopped.

The document overlapping section 19 is provided, for example, adjacent to the upstream side of the platen 2 in the document transport direction, and is a scale for manually recognizing a positioning reference according to the document size when the document is placed on the platen 2. 24 has an upper surface 24a as first guide means. Also, this scale 2
As shown in FIG. 1, the second guide means 4 has an abutment surface 24b orthogonal to the surface of the platen 2 to enable positioning by abutting the original when placing the original.

Accordingly, when the document located at the lowest position of the paper feed tray 5 and the next document are sequentially fed at a predetermined interval, the document is first positioned at the lowest position of the paper feed tray 5. After the original (previous original) is registered on the registration rollers 16, the original is conveyed toward the platen 2 by the conveying belt means 8.

When a predetermined time elapses after the sensor 15 detects the trailing edge of the preceding document in the transport direction, the drive source 21 is driven to push down the pad member 23, and to shift the trailing edge of the preceding document in the transport direction. It is pinched in cooperation with the platen 2. At this time, the endless belt 17 continues to rotate, but may stop.

When the pad member 23 is pushed down, the rear end of the preceding document in the transport direction is jumped up by a step between the abutting surface 24b and the surface of the platen 2 so as to be separated from the upper surface 24a.

On the other hand, the original (next fed original) which is located next to the preceding original located at the lowest position of the paper feed tray 5 and is fed after the completion of feeding of the preceding original is registered by the registration rollers 16. When the sheet is conveyed toward the platen 2 in this state, the rear end in the conveyance direction of the preceding document pushed up by the pressing of the pad member 23 is positioned downstream in the conveyance direction. The leading end of the original in the transport direction enters the trailing end of the preceding original in the transport direction, thereby completing the stacking of the originals.

When a predetermined time elapses after the sensor 15 detects the leading end of the next original in the conveying direction, the driving source 2
1 is driven to push up the pad member 23 upward, so that the registration roller 16 is driven and the endless belt 17 is rotationally moved so that the rear end of the preceding original in the conveying direction and the front end of the next original in the conveying direction are overlapped. After being conveyed onto the platen 2 as it is, the rotation of the endless belt 17 is temporarily stopped at a predetermined reading position, and the recording information provided on the preceding document and the next document is read by a reading device (not shown), and then again. The rotation of the endless belt 17 resumes, and the preceding document and the next document are discharged onto the discharge tray 11 via the discharge unit 10.

At this time, since the preceding document and the next document are reversed by the discharge unit 10, the order of discharging the preceding document and the next document is reverse to the order when the document is placed on the paper feed tray 5. It is discharged without being.

The sensor 15 rotates the endless bell 17 based on the detection of the leading end of the preceding document in the conveying direction, drives the drive source 21 based on the detection of the trailing end of the preceding document in the conveying direction, and performs the next feeding. The drive source 21 is driven in the reverse direction based on the detection of the leading edge of the document in the transport direction, and has a function of stopping the endless belt 17 and starting reading by the reading device based on the detection of the trailing edge in the transport direction of the next document. At this time, since the detection is based on the above-described detection result, it is possible to easily and reliably control entry of the next document to the preceding document and control of the amount of polymerization regardless of the document size.

In the above-described embodiment, the scale 24 is provided with the first and second guide means. For example, as shown in FIGS. Steps 25 and 26 facing upward (FIG. 2) or facing downward (FIG. 3) are formed.
5 and 26, the first guide means 25a,
26a, and the inclined portions 25 of the step portions 25, 26
Original overlapping section 19 'using b and 26b as second guide means
It is also possible to use

At this time, a document pressing member 27 such as a mylar is provided on the downstream side of the inclined portions 25b and 26b in the transport direction with respect to the trailing end portion of the preceding document in the transport direction, whereby the first guide means 25a and 26a And the leading end of the next original in the conveying direction is connected to the rear end of the preceding original in the conveying direction by the first guide means 25a, 2b.
6a, it is possible to prevent a deviation of the preceding document when the document enters the space between the document and the document.

As shown in FIG. 4, a first guide means 28a inclined upward toward the downstream side in the transport direction and a second guide means 28b inclined downward are provided in the middle of the transport path 14. Protruding part 2 with continuous mountain-shaped cross section
8, and a document pressing member 29 such as a mylar that elastically contacts the rear end of the preceding document in the transport direction may be provided downstream of the second guide means 28b in the transport direction.

Further, as shown in FIG.
A document holding member 30 such as a mylar is provided on the downstream side in the conveyance direction at an intermediate position, and the upstream side in the conveyance direction of the document holding member 30 is defined as a first guide means 30a. Is used as the second guide means 30b, the stacking of the originals can be realized without forming the steps 25, 26 and the protruding part 28.

In each of these examples, for example, FIG.
As shown in the figure, conveying rollers 31 and 32 are provided above and below the original stacking section 19 'in the original conveying direction.
By controlling the rotation speed of 32, the transport speed of the next document is made faster than the transport speed of the preceding document so that the next document catches up with the preceding document. It may be transported to the side.

As described above, the next original is inserted between the preceding original and the first guide means 25a, 26a, 28a, 30a, and a part of each original is overlapped, so that the original can be easily and reliably discharged. Can be made the same as the order in which the originals are placed.

[0034]

[Brief description of the drawings]

FIG. 1 is an enlarged explanatory view of a main part of an automatic document feeder according to an embodiment of the present invention.

FIG. 2 is an enlarged explanatory view of a main part of an automatic document feeder according to a first modification of the embodiment of the present invention.

FIG. 3 is an enlarged explanatory view of a main part of an automatic document feeder according to a second modification of the embodiment of the present invention.

FIG. 4 is an enlarged explanatory view of a main part of an automatic document feeder according to a third modification of the embodiment of the present invention.

FIG. 5 is an enlarged explanatory diagram of a main part of an automatic document feeder according to a fourth modification of the embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating the automatic document feeder according to the embodiment of the present invention.

[Explanation of symbols]

 2 Platen 3 Automatic Document Feeder 25 Scale 25a Upper Surface (First Guide Means) 25b Abutting Surface (Second Guide Means)

Claims (7)

[Claims] 1. A two-sheet document fed sequentially from a sheet feed tray is aligned in parallel and sent to a platen, and the two documents read at a reading position of the platen are inverted and discharged. In an automatic document feeder having a feed mode for sequentially discharging a document to a tray, a space in which the leading edge of the next document enters between a transport surface of a transport path for guiding a document from the paper feed tray onto the platen and a trailing edge of the preceding document. An automatic document feeder, wherein a stepped portion for forming the first document is provided, and the next document is superimposed below the rear end of the first document and supplied onto the platen. 2. The automatic document feeder according to claim 1, wherein the stepped portion has an inclined surface that is inclined upward at a downstream side in a document conveying direction. 3. The automatic document feeder according to claim 1, wherein the step portion has an inclined surface that is inclined downward on the downstream side in the document transport direction. 4. The automatic document feeder according to claim 1, wherein the step portion is formed by projecting the conveying surface. 5. The automatic document feeder according to claim 1, wherein said stepped portion is constituted by an elastic member provided to protrude downstream in the document transport direction. 6. The automatic document feeder according to claim 1, wherein the trailing edge of the preceding document and the leading edge of the succeeding document are overlapped before the leading document passes through the stepped portion. 7. The automatic document feeder according to claim 1, wherein a pressing means for pressing a document against said transport surface is provided at said stepped portion.