JPS63196426A - Automatic original document conveyer for both-side image forming device - Google Patents

Abstract

PURPOSE:To prevent an original document from misprocessing its image forming due to the position displacement of the original, by correcting its side edge position through a side guide and a diagonally moving roll which are provided in an original conveying route. CONSTITUTION:A document 5 on an original document tray 4 is fed by a paddle feeder A and set onto a platen 2 by an endless belt 24 through rollers R1, side end position aligning means E, one-side use conveying means B and rollers R2, performing an exposure process. The original 5, when its one-side copying is performed, is discharged being left as it is to a discharge tray 63, while the original 5, when its both- side copying is performed, is fed via rollers R3, side end position aligning means E, one-side use conveying means B and the rollers R2 by reversing the belt 24, thereafter the original 5 is again set onto the platen 2 by switching the belt 24 to its normal rotation, performing an exposure. The side end position aligning means E restricts the side end of the original 5, each time it passes through, to the correct position by a side end guide and a roller which diagonally moves the original 5 to a side of the side end guide. In this way, an image is always formed in a proper position not only when the one-side copying is performed but also when both-sides copying is performed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic document feeder used in a double-sided image forming apparatus such as a double-sided copying machine, and particularly relates to an automatic document feeder that is improved to maintain a good document feed condition. The present invention relates to an automatic document feeder.

[Prior Art] Conventionally, automatic document feeders used in double-sided copying machines and the like include those described in Japanese Patent Application Laid-open Nos. 61-23039 and 61-23040.

These basic structures consist of a document feeding member that feeds double-sided image originals stored in the document storage section one by one, and a single-sided document feeder that transports the originals fed by this document feeding member toward the document setting position on the platen. When the copying operation for one side of the original placed on the platen is completed during double-sided copying, the original on the platen is once separated from the platen and reversed, and then transported again to the original set position on the platen. The apparatus includes a double-sided conveyance means and an ejection conveyance means for discharging the original on the platen when the copying operation for one side of the original placed on the platen is completed.

Problems to be Solved by the Invention Incidentally, in such conventional automatic document feeders such as double-sided copying machines, after aligning the leading edge of the document at a position immediately before the document introduction part to the platen, The document is guided to the upper document setting position so that an image of the document is accurately formed on copy paper or the like.

However, the conveyance path width of the single-sided and double-sided conveyance means is secured to a certain extent to prevent jamming, etc., so that the document may be skewed in the process of being conveyed by each conveyance means. This creates a problem in that the side edges of the document are not aligned with the document set position on the platen, and the document image position is shifted relative to the copy paper or the like.

In particular, in the case of single-sided conveyance means, it is not necessary to set the conveyance path length from the plate stacking section to the platen so long due to the design, but in the case of double-sided conveyance means, the document on the platen is separated once. Since the length of the conveyance path must be set to a certain extent to account for the need to rotate and reverse the document, the positional deviation of the document due to the diagonal feeding of the document described above during the conveyance path of the duplex conveyance means becomes noticeable. appear.

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned problems, and the present invention has been made by focusing on the above-mentioned problems. This invention provides an automatic document conveyance device for image formation.

That is, the present invention includes a document feeding member that feeds single-sided or double-sided image documents stored in a document storage unit one by one, and a document feeding member that conveys the documents sent out by the document feeding member toward a document setting position on a platen. When the image forming process for one side of the original placed on the platen is completed during double-sided image formation, the original on the platen is once separated from the platen position and reversed, and then returned to the original setting position of the platen. a double-sided transport means for transporting the original document placed on the platen, and an ejection transport means for ejecting the original document placed on the platen when the image forming process on one side or both sides of the original document is completed; A side edge position aligning means for aligning the side edge of the document corresponding to the document set position on the platen is disposed in the conveyance path of the conveyance means.

In such technical means, the location where the document storage section is formed may be selected as appropriate, such as adjacent to the side of the platen or on the upper side of the platen.
In consideration of reducing the installation space of the automatic document feeder, it is preferable to provide the document storage section above the platen. In addition, the document feeding member may be appropriately selected such as paddle-shaped or roll-shaped, but the configuration and placement position of each member should be designed appropriately from the viewpoint of not staining the document surface due to pencil writing, etc. It is necessary to. Further, in order to prevent double feeding of documents, it is preferable to attach a retard member for preventing double feeding of documents to a portion corresponding to the document feeding member.

The single-sided conveying means has a document conveyance path between the document storage section and the document entrance of the platen, and conveys the document with a conveyance member appropriately disposed in this conveyance path. After aligning the leading edge of the document with the gate member disposed at the platen entrance of the conveyance path, the gate member is opened at a predetermined timing and the document is conveyed to the document set position on the platen using a conveyance member such as a belt. It is used in the form of a string.

Furthermore, the double-sided conveyance means has a document conveyance path between the document exit portion of the platen and the document inlet portion of the platen, and inverts the document guided out of the platen from the document setting position during this conveyance path. After the document is conveyed while moving, the leading edge of the document is aligned and the document is conveyed to the document setting position. In this case, the conveyance route of the double-sided conveyance means and the conveyance route of the single-sided conveyance means may be provided completely separately, but considering the simplification of the device, it is possible to provide both conveyance routes as possible. It is preferable to share as much as possible, and it is more preferable to share the gate member, the document conveying member on the platen, etc. as much as possible. In addition, the single-sided conveying means requires a means for reversing the document in order to change the document surface for image formation, but the specific configuration of this requires a reversing mechanism provided in the middle of the conveyance path, or a reversing mechanism. The design may be changed as appropriate, such as by making use of the fact that the document conveying member on the platen can be reversely conveyed in the forward and reverse directions without providing a mechanism to substantially reverse the document.

Furthermore, as for the ejection transport means, the design may be changed as appropriate, such as a roll, as long as the original can be ejected from the platen after the image formation process on one side or both sides has been completed, but it must be designed so as not to stain the original. This is desirable.

The side edge position alignment means used includes at least a position regulating member for aligning the side edges of the document, and a guide member for guiding the document to the position regulating member. The shape and arrangement area of the position regulating member may be modified as appropriate as long as the side edges of the document can be aligned sufficiently. Further, although the guide member basically needs to be formed only for document alignment, for example, if a diagonal roll slightly inclined toward the position regulating member is used, it can also be used as a conveying member. Further, the side edge position alignment means may be provided not only in the conveying path of the double-sided conveying means but also in the conveying path of the single-sided conveying means.

In this case, the side edge position matching means may be provided separately, or one side edge position matching means may be provided in the conveyance path portion common to both image transport means.

[Function] According to the above-mentioned technical means, since the side edge position alignment means is provided at least in the middle of the conveyance path of the duplex conveyance means, the side of the document being conveyed by the duplex conveyance means is The end position is aligned corresponding to the original set position on the platen, and in this state, the original is supplied to the original set position on the platen.

[Embodiments] Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

FIG. 1 shows a double-sided copying machine equipped with an automatic document feeder according to an embodiment of the present invention.

In this embodiment, the platen 2 of the copying machine main body 1 is
A cover unit 3 that covers the top in an openable and closable manner is provided, and the automatic document feeder described above is incorporated within this cover unit 3. The basic configuration of the automatic document feeder is a paddle feeder A that feeds, for example, double-sided image originals 5 one by one stored in a document storage tray 4, and a paddle feeder A that feeds the originals 5, which are fed out by the paddle feeder A, to a platen 2. The single-sided conveyance means B conveys the document toward the upper document cellar + position ST, and the document on the platen 2 when the image forming process for one side of the document 5 placed on the platen 2 is completed during double-sided image formation. 5 is once separated from the platen 2 position and reversed, and then transported again to the document setting position ST of the platen 2. At the time when the image forming process on both sides of the document 5 placed on the platen 2 is completed. Original 5 on platen 2
a discharge conveying means for discharging the paper, and the single-sided conveying means B
and side edge position aligning means E, which is disposed in the common conveyance path of the double-sided conveyance means C and aligns the side edge of the document 5 in correspondence with the document set position S<b>2 on the platen 2 .

In this embodiment, a plurality of the paddle feeders A are disposed at an upper portion corresponding to the document exit portion of the document storage tray 4, and a pair of elastically deformable cross-sectional substantially U-shaped paddle feeders A are provided on both sides of the paddle base 11. A paddle 12 is integrally provided, and the paddle base 11 is rotatably supported by a rotation shaft 13 connected to a drive motor (not shown). Furthermore, a glue tart pad 15 for preventing double feeding of documents 5 is disposed at the document exit portion of the document storage tray 4 facing the paddle feeder A.

In addition, the single-sided conveying means B includes a pair of guide plates 21, etc., which move between the document exit portion of the document storage tray 4 and the document inlet portion to the platen 2, as shown in FIGS. 2 and 3 in particular. A first transport port R1 is disposed near the document storage tray 4 of the transport path 22, and the platen 2 of the transport path 22
A second transport roll R2 is disposed on the side, and a gate 23 that can be opened and closed is provided on the platen 2 side of the second transport roll R2 to adjust the timing of supplying the original 5 to the original setting position ST. Furthermore, an endless conveyor belt 24 is provided above the platen 2, which is stretched between a driving roll 25 and a driven roll 26, and the original 5 that has entered the platen 2 is moved to the original setting position. It was designed to be moved to the side.

The drive roll 25 of the conveyor belt 24 is coupled to and driven by a pulse motor 27 that rotates in response to drive pulses from a control device 80, which will be described later. Further, a first position sensor S1 and a second position sensor for detecting the leading edge position of the passing document 5 are provided after the first transport roll R1 and before the second transport roll R2. S2 is provided. As these position sensors S1 and S2, for example, optical type sensors including a light emitting element and a light receiving element are used.

Furthermore, as shown in FIGS. 1 and 4, the double-sided conveyance means C branches from the conveyance path 22 of the single-sided conveyance means B near the document entrance to the platen 2, and is connected to the conveyance roll R1. , the conveyance path 22 located after the installation part position
A pair of guide plates 31 define a branch conveyance path 31 that communicates with the parts, and the platen 2 side inlet of this branch conveyance path 32 is connected to the document entrance of the platen 2 (in this embodiment, the document 5 during double-sided copying). A direction switching gate 33 is provided that guides only the document 5 discharged from the side (which also serves as an exit section) to the branch conveyance path 32 side.
A third conveyance roll R3 is newly disposed in the middle part of the conveyance path 22 that communicates from the end of the branch conveyance path 32 to the document entrance of the platen 2, and is disposed in this conveyance path 22. The second transport roll R2, the gate 23 for aligning the leading edge of the document 5, and the transport belt 24 disposed on the platen 2 are shared with those of the single-sided transport means B.

Further, in this embodiment, the basic configuration of the first to third transport rolls R1 to R3 is as follows:
(specifically 41a to 41C) and this drive roll 4
1, and pinch rolls 42 (specifically, 42a to 42C) that press against the pinch rolls 42
The support shaft 43 is rotatably supported by a bearing portion 45 formed on the free end side of a pair of swing arms 44, for example, with one end serving as a swing fulcrum. A protrusion 41 that protrudes in the radial direction of the fulcrum shaft 46 is provided on one end side of the fulcrum shaft 46 that serves as a fulcrum for the swinging arm 44, and an electromagnetic actuator 48 (specifically Target is 48a or 48
The operating rod 49 of C) is connected, and the electromagnetic actuator 48
During operation, the operating rod 49 moves backward to move the swing arm 44 upward or downward, thereby releasing the pinch roll 42 from the drive roll 41. A spring 50 is attached to the protruding piece 47 to bias the operating rod 49 of the electromagnetic actuator 48 in the advancing direction. Also, code 51 (specifically 51a to 51C)
is a drive motor that drives the drive roll 41 based on a control signal from a control device.

Further, as shown in FIG. 1, the above-mentioned discharge conveyance means
It is disposed near the original setting position ST side of the platen 2, and is also used as a means for ejecting the original 5 whose copying operation has been completely completed from the original ejection opening located on the opposite side of the original entrance of the platen 2. the conveyor belt 24,
A guide member 61 that constitutes a conveyance path for the discharged original 5
and a paper discharge roll 62 that delivers the document 5 discharged along the guide member 61 to the discharge tray 63.

Furthermore, in this embodiment, the side edge position aligning means E, as particularly shown in FIGS. 2 and 5,
2, a portion of the transport path 22 located on the rear side from the connection part with 2;
In other words, the diagonal roll R disposed in the conveyance path 22 portion common to the single-sided conveyance means B and the double-sided conveyance means C is disposed corresponding to the side edge of the document setting position ST on the platen 2. It consists of a side guide G and a side guide G. The skew roll R includes a skew drive roll 72 that is disposed slightly inclined toward the side guide G with respect to the original document feeding direction and is appropriately driven by a skew drive motor 71, It is composed of a diagonal pinch roll 74 which is placed in pressure contact with a drive roll 72 via a spring member 73, and the side guide G is formed to have a substantially U-shaped cross section.
It is disposed on one side of the pair of guide plates 21 constituting the transport path 22, and the bottom surface of the U-shaped groove 76 serves as a side edge alignment surface 77 of the original 5.

Further, in this embodiment, the control device 80 of the automatic document feeder is comprised of a microcomputer system as shown in FIG. In the figure, signals from the copying switch 3c, each position sensor S1.82, etc. are input as data to the control unit 82 via the input interface 81. The control unit 82 provides processing procedures to the CPU 83 that processes the entire system, the RAM 84 that exchanges data during processing with the CPU 83, and the CPU 83. It consists of a ROM85 that stores programs, etc., and the ROM85 has the following:
A program for controlling document conveyance operation and copying timing as shown in the flowchart of FIG. 7 is stored in advance, and the CPU 83 executes the program based on data given via the input interface 81 and outputs Various output devices are connected via the interface 86, specifically, the drive motor 14 of the paddle feeder A, the pulse motor 27 for driving the conveyor belt 24, and each conveyor roll R1.
Electromagnetic actuators 48a to 48C for nipping and releasing R1 to R3, drive motors 51 for each of the transport rolls R1 to R3, drive motor 64 for the discharge roll 62 of the discharge transport means, various copying parts 90 necessary for copying operations, etc. These are controlled by sending out control signals.

Next, the operation of the automatic document feeder according to this embodiment will be explained in the seventh step.
The explanation will be centered on the flowchart shown in the figure.

When copying the double-sided image original 5, the operator first selects the double-sided copy mode using a mode selection switch not shown, and then turns on the copy switch 3c.

At this time, the control section 82 operates the paddle feeder A and each of the transport rolls R1 to R3 in accordance with the ON operation of the copy switch SC to start feeding the original 5 (step ST1). Then, at the position shown in FIG. 8 P1, the raw material N5 is fed out by the paddle feeder A and then conveyed by the first conveyance roll R1 in a nip state. Then, the control unit 82 determines whether or not the first position sensor S1 has detected the leading edge of the document 5 (step ST2), and if determined, stops the paddle feeder A and also stops the nip of the transport roll R2. The operation is canceled and the gate 23 which was in the open state is closed (steps ST3 to ST5). At this stage, the document 5 is sequentially conveyed along the conveyance path 22 by the first conveyance roll R1, and the leading edge of the document 5 reaches the skew roll R, as shown in FIG. 8 P2.

During this time, the control section 82 determines the point in time when the leading edge of the document 5 reaches the skew roll R position, for example, based on the signal from the position sensor S1 and considering the document conveyance speed of the conveyance roll R1 (step 5T6). , release the pinch roll 42 of the first transport roll R1 from the position shown by the imaginary line to the position shown by the solid line in FIG. 5 is released for a sufficient period of time to align the side edge positions of 5 (step 5T7).

Then, as shown in FIG. 5, even if the document position in the transport path 22 is deviated from the document set position ST on the platen 2, the document 5 nipped by the skew roll R is The document 5 is obliquely fed toward the side guide G from the state shown by the solid line in the figure to the position shown by the imaginary line, and the side edge position of the document 5 is aligned with the side edge alignment surface 77 of the side guide G. During this time,
Since the nipping operation of the first transport roll R1 is temporarily canceled, even if the trailing edge of the document is located at the first transport roll R1, the alignment operation of the document 5 will be impaired. You won't be hit.

Thereafter, the original 5 conveyed by the skew roll R is shown in FIG.
3, it moves toward the second transport roll R2. Then, the control section 82 controls the second position sensor S2.
In step S, it is determined whether or not the leading edge of the document 5 has been detected.
(8) If it is determined, the biasing force of the spring member 49 is released by deactivating the electromagnetic actuator 48b when the original 5 passes the second transport roll R2, as shown in FIG. , the pinch roll 42 at the solid line position n is returned to the imaginary line position, and the second transport roll R
2 again, and the leading edge of the document 5 is placed at the gate 2.
When the third position is reached, the gate 23 is opened (step ST9.5T10).

Then, as shown at P4 in FIG. 8, the document 5 is transported by the second transport roll R2, and the pulse motor 27 for driving the transport belt 24 is moved in synchronization with the opening timing of the gate 23. is driven by a predetermined pulse, and the document 5 that has entered the second surface of the platen is conveyed by the conveyor belt 24 to the one document set position 1tsT (step 5TII). In this state, the control section 82 causes a predetermined copying operation to be performed, and one side of the original 50 is transferred to the copy paper (
(not shown) (step 5T12).

Thereafter, the control unit 82 determines whether the copy mode is the "double-sided copy mode j" (step 13), and if it is not the "double-sided copy mode", immediately causes the document ejection operation to be described later to be performed (step 5T25). ) is in the "double-sided copying mode", the pulse motor 27 for driving the conveyor belt 24 is rotated in the reverse direction by an appropriate drive pulse amount to move the conveyor belt 24 in the reverse direction (step 5).
T14). In other words, the original 5 set at the original setting position ST is sent out from the original entrance side of the platen 2 to the outside of the platen 2 by the conveyor belt 24 (step 5T).
14). In this case, as shown in FIG. 10, the original 5, which has already been copied on one side and which has been sent out of the platen 2, is guided to the branch transport path 32 side by the direction switching gate 33, and is bent by the third transport roll R3. Figure 8 P5
In addition to reaching the position shown in (steps 5T15 and 5T16), the control unit 82 releases the nip operation of the second transport roll R2 at a predetermined timing and closes the gate 23 (steps 5T15 and 5T16).

Then, the original 5 transported by the third transport roll R3
As shown at P6 in FIG. 8, the roller moves from the branched conveyance path 32 to the conveyance path 22 and reaches the skew roll R portion. At this time, the control section 82 determines the point in time when the leading edge of the document 5 (indicated by the dotted line in the middle of FIG. 9) reaches the skew roll R portion, based on the timing at which the conveyor belt 24 starts to be driven in reverse (step 5T17). , at the time when it is determined, the pinch roll 42c of the first conveyance roll R3 is released from the position shown by the imaginary line in FIG. Specifically, it is released for a sufficient time to align the side edge positions of the original 5 (step 5T18). Then, the fifth
As shown in the figure, even if the position of the document that has reached the conveyance path 22 from the branch conveyance path 32 deviates from the document set position ST on the platen 2, the document 5 nipped by the skewed roll R is , the document 5 is obliquely fed toward the side guide G from the state shown by the solid line in FIG.

During this time, the nipping operation of the third transport roll R3 is temporarily canceled, so even if the trailing edge of the document is located at the third transport roll R3, the alignment operation of the document 5 will not be possible. will not be harmed.

Thereafter, the original 5 conveyed by the skew roll R is shown in FIG.
As shown in 1, it moves toward the second transport roll R2. Then, the control section 82 controls the second position sensor S2.
Step 5
T19), if it is determined, as shown in FIG. 10, the electromagnetic actuator 48b is deactivated when the document 5 passes the second transport roll R2, so that the urging force of the spring member 49 is used. The pinch roll 42 located at the solid line position is returned to the imaginary line position and the second transport roll R2 is operated to nip again, and when the leading edge of the document 5 reaches the gate 23 position, the gate 23 is opened (step 5T20.5T21).

Then, as shown at P8 in FIG. 8, the document 5 is transported by the second transport roll R2, and the pulse motor 27 for driving the transport belt 24 is moved in synchronization with the opening timing of the gate 23. is driven by a predetermined number of pulses, and the document 5 that has entered the second surface of Braden is sent to the document hit position ST by the conveyor belt 24 (step 5).
T22). In this state, since the surface of the original 5 facing the platen 2 is reversed compared to when it is initially set at the original setting position ST, the control section 82 performs a predetermined copying operation, and the original ¥R5 The other side of the image is copied onto copy paper (step 5T23').

After that, the control unit 82 performs steps 5T14 to 5T14.
Step 5T24) repeats the operation of T22, moves the original as shown in P9 to Pll in FIG. The paper ejection roll 62 is driven to eject the original 5 to the position shown at PI3 in FIG. 8 (step 25).

In the above embodiment, the skew O-ru R is such that the skew roller 74 is always placed in pressure contact with the skew drive roll 71, so that the original 5 is always kept in contact with the skew drive roll 71.
The surface will be rubbed, and this will cause the original N5 to be easily soiled if it is a pencil-written original 5. For example, as shown in FIG. 11, the electromagnetic actuator 75
etc., the document 5 is transferred to the second transport roll R2.
By temporarily canceling the nipping operation of the skew rolls R when the paper is nipped, it is possible to reduce stains on the pencil-written manuscript 5 by the amount of time during which the skew rolls R are not in contact with each other.

[Effects of the Invention] As described above, according to the automatic document feeder of the double-sided image forming apparatus according to the present invention, the document may be fed diagonally during the document conveyance path and may be moved from the document set position on the platen. Even if the original is deviated, it is aligned to the correct document side edge position corresponding to the original setting position on the platen in the transport path, so the original can be accurately aligned to the original setting position, and the original can be adjusted accordingly. , it is possible to effectively prevent errors in image forming processing due to misalignment of the original.

[Brief explanation of the drawing]

Figure 1 is a schematic explanatory diagram showing one embodiment of an automatic document feeder of a double-sided image forming apparatus according to the present invention, and Figures 2 to 4 are
The figure is a partial view from the direction of arrows ■, ■, and ■ in Figure 1.
The figure is a view in the direction of arrow V in FIG. 2, and FIG. 6 is a block diagram showing the control device of the automatic document feeder in the embodiment.
FIG. 7 is a flowchart showing the operation of the control device, FIG. 8 is an explanatory diagram showing the document conveyance process in the embodiment, and FIGS. 9 and 10 are flowcharts showing the operating state of the automatic document feeder during the document conveyance process. Section ■ in Figure 8, cross-sectional explanatory diagram of section X, 1st
FIG. 1 is a perspective view showing a modification of the skew roll used in the embodiment. [Explanation of symbols] (A) Paddle feeder (document feeding member) (B)
... Conveyance means for one side (C) ... Conveyance means for both sides (D) ... Conveyance means for discharge (E) ... Side edge position alignment means (R) ... Oblique roll (G) ... ...Side guide (2)...Platen (4)...Document storage tray (document storage section) (5)...
・Manuscript patent applicant Fuji Xerox Co., Ltd. Agent
Patent Attorney Tomohiro Nakamura (2 others) Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1) A document feeding member that feeds single-sided or double-sided image documents stored in a document storage section one by one, and a document feeding member that directs the documents fed by the document feeding member toward a document setting position on a platen. When the image forming process for one side of the document placed on the platen is completed during double-sided image formation, the document on the platen is once separated from the platen position and reversed, and then the document is placed on the platen again. It includes a double-sided transport means for transporting the original to the set position, and an ejection transport means for ejecting the original on the platen at the time when the image forming process on one side or both sides of the original placed on the platen is completed, and at least the above-mentioned An automatic document conveying device for double-sided image forming means, characterized in that a side edge position aligning means for aligning the side edges of a document corresponding to the document set position on a platen is disposed in the conveying path of the double-sided conveying means. 2) The side edge position alignment means includes a diagonal roll that rotates in a document feeding direction that is slightly inclined with respect to the direction of the document conveyance path, and a side edge position alignment device that is disposed on the document feeding direction side of the diagonal roll. 2. The automatic document conveying device for a double-sided image forming apparatus according to claim 1, further comprising a side guide for regulating the side edge position of the document.