JPH0688718B2 - Automatic document feeder - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention relates to an automatic document feeder for performing an aligning correction by temporarily switching back separated sheets.

[Background of the Invention] Generally, in a copying machine, a document is placed on a platen glass, and an image of the document is copied onto a sheet.
The method of feeding the originals includes a method of feeding the originals one by one onto the platen glass by the operator's hand, and a method of automatically feeding / discharging the originals by an automatic original feeding device.

In this automatic document feeder, a plurality of documents are set with their respective document surfaces facing the paper feed stacker and are sent from the last page of the document to the copying machine. Then, after the copying operation, the document is reversed and stored in the paper discharge stacker. In this way, the discharged originals are stored in the discharge stacker in page order, and the copied sheets are also stored in the discharge tray in page order.

[Problems of the Background Art] However, when the automatic document feeder is attached to a copying machine capable of double-sided copying and a plurality of originals having images formed on only one side are copied on both sides of paper. Is
The following problems occur. That is, when an original is fed from the last page to the copying machine with the original surface facing downward, if the original is an even number, double-sided copying can be completed in the order of pages. However, if the number of originals is odd, there is a drawback that the topmost sheet of the copied sheets, that is, the upper surface of the first copy page is blank.

On the other hand, in the automatic document feeder, the document must be set along the reference line on the platen glass.
Therefore, the automatic document feeder is provided with an aligning mechanism that conveys a document along the reference line by using an aligning roller inclined toward the reference line. Here, in order for the aligning mechanism to surely perform the aligning, the document conveyed on the platen glass must be in a freely movable state. However, in the conventional automatic document feeder, for this reason, the aligning mechanism needs to have a length twice as long as the maximum document length, resulting in an increase in size of the device.

[Object of the Invention] The present invention has been made based on the above-mentioned circumstances.
An object of the present invention is that even when two-sided copying of an original is performed on a sheet, the first page of the finished copy will not be blank regardless of the number of originals, the aligning can be performed reliably, and the apparatus can be used. An object of the present invention is to provide an automatic document feeder which can be configured compactly.

[Outline of the Invention] In order to achieve the above-mentioned object, an automatic document feeder according to the present invention is provided on one side of a platen glass, upstream of a document transport direction, and above the platen glass.
An original placing table for placing a plurality of originals in a state where the surface to be copied faces upward, a take-out mechanism for taking out the originals placed on the original placing table one by one from the upper side, and a lower side of the original placing table. A switchback unit that is provided so that the copy surface of the document faces downward, and that is provided between the document placing table and the switchback unit,
It is provided between the platen glass and the switchback unit, and the first conveyance path that guides the document taken out by the takeout mechanism by making a U-turn to the switchback unit so that the copy surface of the document faces downward. , An aligning roller for aligning the position of the original on the platen glass with a predetermined position,
A second conveyance path that is provided between the switchback unit and the aligning roller and guides the document output from the switchback unit to the aligning roller, and a second conveyance path that is provided in the switchback unit and is guided by the first conveyance path. The original is engaged with the original, and the original is fed out in the direction opposite to the original conveying direction guided by the first conveying path, and the leading edge of the original is conveyed to the aligning roller via the second conveying path. When engaged,
It is characterized in that it is provided with a conveyance mechanism for releasing the engagement with the document.

[One Embodiment of the Invention] One embodiment of an automatic document feeder according to the present invention will be described in detail below with reference to the accompanying drawings.

In this embodiment, the automatic document feeder 10 is provided on a copying machine 12 capable of double-sided copying. Since the structure of the copying machine 12 is well known, detailed description thereof will be omitted.

The automatic document feeder 10 is roughly provided with a separating / conveying unit 14 and a platen glass conveying unit 16. The separating / conveying unit 14 is provided to separate and convey the stacked originals one by one, and is fixed on a caster table 18 provided adjacent to one side of the copying machine 12. In this way, the separating / conveying unit 14 is provided independently of the copying machine 12.

This separation / conveyance unit 14 is fixed to the upper surface of the caster table 18,
Document insertion hole 20a on one side and document ejection hole 20b on the other side
And a document stacker 22 which is mounted on the housing 20 adjacent to the document insertion hole 20a and on which the documents P are placed in a stacked state.

On the other hand, the platen glass conveying section 16 is provided to convey the originals taken out one by one from the separating and conveying section 14 on the platen glass 24 of the copying machine 12, and the copying machine via a hinge (not shown). Is rotatably attached to the upper surface of the. In this way, the platen glass conveying section 16 is
The platen glass 24 can be opened by being rotated.

The platen glass conveying section 16 has a cover 26 having a document intake hole 26a provided opposite to the document extraction hole 20b and a document discharge hole 26b provided on the opposite side of the document intake hole 26a. Is equipped with. The document discharge hole 26b
A discharged document stacker 28 is attached to the upper edge of the other side of the copying machine 12 adjacent to. Inside the cover 26, a plurality of aligning rollers 3 facing the document intake hole 26a are provided.
0, and a conveyor belt 32 having one end facing the aligning roller 30 and the other end facing the document discharge hole 26b.

These aligning rollers 30 are, as shown in FIG.
It is coaxially fixed to the common rotating shaft 30a. This rotating shaft 3
The center axis C of 0a is inclined along the conveyance direction F by a slight angle A from the axis R orthogonal to the conveyance direction F of the document P. Since the aligning roller 30 is arranged so as to be slightly inclined with respect to the document conveyance direction F in this manner, the document follows the predetermined reference line of the platen glass 24. In this way, the originals along the reference line are
Is transported on the platen glass 24.

Here, when the originals are placed one by one on the platen glass 24 by the operator's hand, the platen glass transport unit 16
Is rotated via a hinge, and the platen glass 24 is opened.

Next, the configuration of the separation / conveyance unit 14 will be described in detail with reference to FIG.

In the housing 20, a document support table 34 is arranged in a continuous state with the document stacker 22 through the document insertion hole 20a. The document support table 34 is provided at the front end of the document for the housing 20.
The document stacker 22 supports the rear end of the document outside the housing 20. Document support 34 in housing 20
A pickup roller 36 is rotatably provided above the. The pickup roller 36 engages with the uppermost one of the documents placed on the document support table 34, and the rotation of this picks up the documents one by one. Adjacent to the pickup roller 36, there is provided a first detector S1 which detects that a document is set on the document support 34 and turns on the power of the automatic document feeder 10. The first detector S1 is composed of a lever-type photo sensor.

The pickup roller 36 described above has a shaft at one end of a frame 38.
It is rotatably attached via 40. The other end of the frame 38 is rotatably attached to a shaft 42, both ends of which are rotatably attached to the side surface of the housing 20.
A pulley 44 is coaxially fixed to the shaft 42 while the shaft 40
Also, the pulley 46 is coaxially fixed. Both pulleys 44,46
A timing belt 48 is wound between them, and thus the pickup roller 36 is rotationally driven via the timing belt 48 by the rotation of the shaft 42.

A paper feed roller 50 is coaxially fixed to the shaft 42.
A separating roller 52 is provided in a state of rolling contact with the paper feeding roller 50. The rolling contact portion is provided so as to face the original take-out position. Further, the paper feed roller 50 is rotated clockwise in FIG. 3, and the separation roller 52 is also rotated clockwise.

A stopper 54 is provided at the above-mentioned document take-out position so as to be movable back and forth. The stopper 54 is fixed to a shaft 56, and the shaft 56 is rotated by a solenoid 58. A lever 60 is rotatably attached to the shaft 56. The tip of the lever 60 can contact the protruding end 62 of the frame 38. While the protruding end 62 is being pressed by the lever 60, the pickup roller 36 is separated from the document, and the document is not taken out. Thus, when the shaft 56 faces the stopper 54 so as to close the original take-out position by turning off the solenoid 58, the stopper 54 engages the lever 60 so that the protruding end 62 is pushed downward. ing.

The solenoid 58 is turned on by pressing the copy start button of the copying machine 12. Further, a second detector S2 for detecting that the original has been taken out is provided downstream of the rolling contact portion between the paper feed roller 50 and the separation roller 52 along the taking-out direction of the original. . The second detector S2 is composed of a photo sensor.

In the housing 20 described above, a guide path 64 for guiding the taken-out original document to below the original document support table 34 is provided. The guide path 64 is formed in a U shape, and the document support table 34
The original taken out from the original is guided to the lower side of the original support table 34 in the inverted state. At the base end portion of the guide path 64, a registration roller 66 and a pressure roller 68 are provided in a state of rolling contact with each other. The rolling contact portions of these rollers 64, 68 are located inside the guide path 64. In addition, a third detector S3 for detecting that the document has entered the guide path 64 is provided on the upstream side of the rolling contact portion in the document transport direction.

On the other hand, below the separation roller 52, the conveyance roller 70 is provided so that the lower end portion thereof is located inside the switchback portion of the guide path 64. A lever 72 is provided at the lower end of the transport roller 70 so as to be capable of pressure contact. The lever 72 is driven by a solenoid 74.

An opening 76 is formed at the end of the guide path 64, that is, at the portion of the housing 20 facing the switchback portion.
Further, a fourth detector S4 for detecting the passage of the document is provided on the upstream side of the guide roller 64 in the document transport direction from the transport roller 70. Here, the switchback portion, which is the lower portion of the guide path 64, is inclined so as to slightly rise toward the terminal end.

A branch guide path 78 extending toward the document take-out hole 20b is provided at the lowermost portion of the guide path 64. A switchback seat 80 is provided at the joint between the guide path 64 and the branch guide path 78. This sheet
Reference numeral 80 allows a document taken out from the document support table 34 to move toward the conveyance roller 70, but moves a document sandwiched between the conveyance roller 70 and the lever 72 toward the document support table 34. Is made of a thin synthetic resin so that only the movement toward the branch guide path 78 is permitted.

At the exit of the branch guide path 78, a static elimination brush 82 for eliminating static electricity on the document is provided.

On the other hand, in the platen glass conveying section 16, the cover 26
Inside the document intake hole 26a, facing the document intake hole 26a
A fifth detector S5 is provided which detects that the leading edge of the original has entered 6a. Further, a shutter 84 is provided between the aligning roller 30 and the transport belt 32 so as to close the document transport path by a solenoid 86.

The upper portion of the housing 20 of the separating / conveying unit 14 can be opened, and the upper portion is removed and the lower portion is exposed with the original conveying path as a boundary. In this way, even if the original is jammed during the removal, the jammed original can be easily removed by opening the upper part of the housing.

Further, in FIG. 3, reference numeral 88 indicates a fixed frame for attaching the separating / conveying unit 14 to the caster table 18.

The operation of the automatic document feeder configured as described above will be described below with reference to the timing chart shown in FIG.

The originals P are stacked on the original stacker 22 with the original face up and the lowest number on the top, and the leading edge of the originals is placed on the original support table 34 through the original insertion hole 20a. Brought to. The first detector S1 is turned on by the manuscript placed on the manuscript support table 34, and the automatic manuscript feeder
When the power of 10 is turned on, the document can be fed. still,
In this state where the document can be fed, since the solenoid 58 is off, the stopper 54 faces the document take-out position, and the document is not taken out.

When the copy start button of the copying machine 12 is pressed, the solenoid 58 is turned on and the shaft 50 rotates counterclockwise in FIG. In this way, the stopper 54 is retracted from the original take-out position, the tip of the lever 60 is separated from the projecting end 62 of the frame 38, and the shaft 42 is rotated in the clockwise direction. By the rotation of the shaft 44, the paper feed roller 50 and the pickup roller 36 are rotated clockwise, respectively, and the frame 38 is also rotated clockwise about the shaft 42. Then, the pickup roller 36 comes into contact with the uppermost one of the originals, and the rotation of the pickup roller 36 causes the originals to be fed one by one from the upper side, that is, toward the paper feed roller 50 in order from the youngest page and the original surface. Is taken out with the side facing up.

The original taken out from the original support 34 passes through the second detector S2, and the second detector 34 is turned on. By this turning on, the separation roller 52 starts to rotate in the clockwise direction, the solenoid 58 is turned off, the lever 60 rotates in the clockwise direction, the protruding end 62 of the frame 38 is pushed in, and the pickup roller 36 moves upward. Pushed up. In this way, even if the original is rotated by the rotation of the pickup roller 36,
Even if the sheets are taken out, the rotation of the separation roller 52
The second document is retracted to the document support table 34, and only one document is taken out.

When the thus separated document enters the guide path 64 and the third detector S3 is turned on, a predetermined time t1 has elapsed from the time when the detector was turned on, and the rotation of the paper feed roller 50 and the separation roller 52 is stopped. At the same time, the registration roller 66 and the conveyance roller 70 start rotating counterclockwise. Here, the lever 72 is brought into contact with the conveyance roller 70 by the solenoid 74. After turning on the third detector S3, the document is brought to the rolling contact portion between the registration roller 66 and the pressure roller 68. The original is deflected at the contact portion, and the orientation of the original is registered.

The original is guided along the guide path 64 by the rotation of the registration roller 66, the sheet 80 is pushed away at the junction of the branch guide path 78, and the original surface is directed downward.
It is sandwiched between 72 and. Then, the original is this conveyance roller.
The document is conveyed further by the rotation of 70, and the leading edge of the document
It is taken out of the housing 20 through the opening 76 of the 20.
Here, when the trailing edge of the document passes the fourth detector S4, the rotations of the registration roller 66 and the conveyance roller 70 are stopped. In this way, the transportation of the document is temporarily stopped.

After that, when a predetermined time t2 elapses after the fourth detector S4 detects the trailing edge of the document, the registration roller 66 and the transport roller 66
70 is rotated clockwise. In this way, the document is fed back through the guide path 64. Here, at the joint between the guide path 64 and the separation guide path 78, the document is a registration roller.
The sheet 80 is prohibited from being conveyed toward 66, and is guided toward the document take-out hole 20b through the separation guide path 78.

The front end of the original taken into the cover 26 of the platen glass conveying unit 16 through the original taking-out hole 20b and the original taking-in hole 26a is detected by the fifth detector S5. In response to this detection, the aligning roller 30 is rotated for a predetermined time t3. Further, after this detection, a predetermined time t4 elapses, the rotation of the conveyance roller 70 and the registration roller 66 is stopped, the solenoid 74 is turned off, and the lever 72 moves the conveyance roller 72.
Away from.

In this way, the original is
The document is conveyed while being aligned, and the document is stopped when its leading end contacts the shutter 84. In this way, the document is aligned without being pinched by the transport roller 70 and the lever 72.

A predetermined time t5 after the fifth detector S5 detects the leading edge of the document.
After that, the solenoid 86 is turned on to open the shutter 84, and after a predetermined time t6, the aligning roller 30 and the conveyor belt 32 are driven for a predetermined time t7.
In this manner, the document is conveyed on the platen glass 24 with the document surface facing downward and set at a predetermined position. Then, when the copying operation is completed, the transport belt 32 is driven again, and the original is ejected from the platen glass 24 and is accommodated in the ejected original stacker 28.

Note that the next operation of taking out the original is performed when the fourth detector S4 detects the rear end of the original twice.

Here, the paper copied in the copying machine 12 is ejected as it is in the case of single-sided copying, and is temporarily held in the copying machine 12 in the case of double-sided copying, and the paper is turned upside down. The image of the next original is copied on the back side.

According to the automatic document feeder of the embodiment as described above, the following effects can be obtained.

First, the originals are set on the original stacker 22 with the original side facing upward, and the originals are set in the page order of the originals from the upper side to the lower side. The front and back are reversed. In this way, the document is conveyed onto the platen glass 24 with the document surface facing down. Therefore, even in the case of single-sided copying, the page order of the originals matches the page order of the copied papers, and even in the case of double-sided copying, even if the number of originals is even or odd, it is copied. The first sheet of paper is never blank.

Next, at the time of aligning, since the document is not pinched by the carry-out roller 70 and the lever 72, the document is simply restrained by the aligning roller 30,
The aligning roller 30 is not overloaded, and the aligning is surely performed.

Also, since the original is inverted and switched back,
Compared to the conventional case where the part for taking out the document and the part for aligning the document are connected in series, the length occupied by the separating / conveying unit 14 can be shorter, and the automatic document feeding device can be used.
The overall width of 10 is set short.

Further, since the original document which is switched back through the opening portion 76 is made to be ejected to the outside of the housing 20, the load applied to the original document at the time of aligning is further reduced, and the taken original document is located below the original document stacker 22. Since it is located at, there is no need to provide a separate cover, which is economical.

[Effects of the Invention] As described in detail above, the automatic document feeder according to the present invention is provided on one side of the platen glass, upstream of the document conveying direction, above the platen glass, An original placing table on which the originals to be copied are placed upward, a take-out mechanism for taking out the originals placed on the original placing table one by one from above, and provided below the original placing table. , A switchback unit for accommodating the copy surface of the document faces downward, and a document provided by the extraction mechanism, which is provided between the document placement table and the switchback unit, is turned to the switchback unit to make a U-turn, The first aligning path is provided between the platen glass and the switch pack part, which guides the copy surface of the document facing downwards, and aligns the position of the document on the platen glass to a predetermined position. And a second conveying path that is provided between the switchback unit and the aligning roller and guides the document output from the switchback unit to the aligning roller, and the first conveying path that is provided in the switchback unit. The original guided by the path is engaged, the original is sent out in a direction opposite to the direction in which the original guided by the first conveying path is conveyed, and then is conveyed to the aligning roller via the second conveying path. The present invention is characterized by further comprising a conveyance mechanism that releases the engagement with the document when the leading edge of the document is engaged.

Therefore, according to the present invention, even when two-sided copying of a document is performed on a sheet, the first page of the finished copy will not be blank regardless of the number of documents, and the aligning can be surely performed. Provided is an automatic document feeder which can configure the apparatus compactly.

[Brief description of drawings]

FIG. 1 is a front view schematically showing a case in which an embodiment of an automatic document feeder according to the present invention is applied to a copying machine, FIG. 2 is a top view showing an inclined state of an aligning roller, and FIG. Is a front sectional view showing the internal structure of the automatic document feeder, and FIG. 4 is a timing chart for explaining the operation of the automatic document feeder. 10 ... Automatic document feeder, 22 ... Document stacker, 24 ... Platen glass, 30 ... Aligning roller, 34 ... Document support,
36 ... Pickup roller, 50 ... Paper feeding roller, 52 ... Separation roller, 64 ... Guide path, 70 ... Conveying roller, 72 ... Lever, 78 ...
Separation conveyance path, 80 ... sheet.

Claims (1)

[Claims] 1. A platen glass is provided on one side of the platen glass, upstream of the original conveying direction, and above the platen glass.
An original placing table that places multiple originals with the surface to be copied facing upward, a take-out mechanism that takes out the originals placed on the original placing table one by one from above, and below the original placing table. The switchback section is provided between the document mounting table and the switchback section. The switchback section is provided between the document mounting table and the switchback section. The switchback section makes a U-turn to the switchback section. Provided between the platen glass and the switchback section, and the first conveyance path that guides the original copy surface facing downward.
A second aligning roller that aligns the position of the document on the platen glass with a predetermined position and a switchback part and an aligning roller, and guides the document emitted from the switchback part to the aligning roller. Of the original document guided by the first transport path, which is provided in the switchback section and the original transport path of the original document, and the original document is guided in a direction opposite to the transport direction of the original document guided by the first transport path. And a conveying mechanism for releasing the engagement with the original when the leading edge of the original is engaged with the aligning roller via the second conveying path. apparatus.