JPH1025047A - Sheet turn-over device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute the continuous turn-over process of a sheet by sending out a sheet reversely fed in a sheet turn-over drum to a sheet discharge guide by means of rotationally driven discharge rollers, and sending a new sheet into a stand-by passage even if a sheet exists in the stand-by passage. SOLUTION: By passing the extreme end of a copying paper sheet P through a first sheet detecting sensor 25, a turn-over roller 20 is normally rotated. At this time, a copying paper sheet P carried out on the sheet discharge guide 21 side is pinchedly held with discharge rollers 22, and the copying paper sheet P is not changed into a normal feed state, because a gap of about 4-5mm is formed between the guide face 16 of a sheet turn-over drum 17 and the turn-over roller 20. When a new copying paper sheet P is further sent into the sheet turn-over drum 17, it is brought in contact with the copying paper sheet P during reverse feeding so as to be bent on the turn-over roller 20 side, pushed against the turn-over roller 20 by a sheet energizing guide 23 positioned on the upper side, and it begins to be normally fed in the turn-over drum 17 by normal rotation of the turn-over roller 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet reversing device for reversing a continuously conveyed sheet upside down and continuously ejecting the same, and more particularly, in the middle of a conveying path of a sheet conveyed from a copying machine to a sorter. It is suitable to be incorporated in

[0002]

2. Description of the Related Art In various office machines such as copying machines,
In many cases, it is necessary to reverse the top and bottom of a sheet such as a copy sheet inside an office machine. For example, when printing on both sides of a copy sheet with a copying machine or the like, a copy sheet having a predetermined print on one side is temporarily sent out from a sheet conveying path to a standby path for reversing, and from this standby path. By returning to the sheet conveying path again, the front and back of the copy sheet are reversed, and a predetermined print is performed on the other surface.

[0003]

In the conventional sheet reversing apparatus, the sheet can be fed only when the reversing standby path connected to the sheet conveying path is empty. While it is on the road, it is difficult to feed a new sheet, and it has been difficult to perform continuous sheet reversal processing.

As described above, in order to cope with high-speed processing of a sheet in a copying machine or the like, the sheet must be capable of continuously reversing the sheet irrespective of the sheet processing speed.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet reversing apparatus capable of feeding a new sheet into a standby path and performing a continuous sheet reversing process even if the sheet exists in the standby path. is there.

[0006]

SUMMARY OF THE INVENTION A sheet reversing device according to the present invention comprises a cylindrical sheet reversing drum having an inner peripheral surface serving as a sheet guiding surface, and a sheet reversing drum for applying a sheet from outside the sheet reversing drum. A sheet introduction guide for introducing the sheet into the inside of the sheet reversing drum, and provided in the sheet reversing drum in the vicinity of the inner peripheral surface of the sheet reversing drum so as to be freely rotatable forward and backward, and carried into the sheet reversing drum from the sheet introducing guide. A reversing roller for sequentially feeding or reversing a sheet to be fed in the sheet reversing drum, a sheet discharge guide for sending a sheet fed back in the sheet reversing drum to the outside of the sheet reversing drum, and the sheet reversing drum. And a discharge roller that rotates and drives the sheet to be fed back into the sheet discharge guide.

According to the present invention, when a sheet is introduced from the sheet introduction guide into the sheet reversing drum, the reversing roller rotates forward and feeds the sheet sequentially in the sheet reversing drum. When the end of the sheet comes out of the sheet introduction guide and comes into contact with the inner peripheral surface of the sheet reversing drum due to the elastic force of the sheet itself, the reversing roller reverses and starts reverse feeding of the sheet, and the leading end is discharged. The sheet is discharged from the sheet reversing drum from the sheet discharge guide by a roller.

When the sheet starts to be conveyed by the discharge roller, the reversing roller turns forward again, and feeds the next new sheet introduced into the sheet reversing drum from the sheet introduction guide in the sheet reversing drum. In this case, in the sheet reversing drum, the sheet to be sent to the sheet ejection guide side by the ejection roller coexists, but a new sheet to be sequentially fed is the same as the sheet to be sent backward. Since the sheet is located inside, a new sheet comes into contact with the reversing roller, and the sequential feeding is smoothly performed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the sheet reversing device of the present invention, it is desirable that the peripheral length of the inner peripheral surface of the sheet reversing drum is set longer than the length along the sheet conveying direction. It is desirable that the gap between the inner peripheral surface of the reversing drum and the reversing roller is set to be larger than twice the thickness of the sheet.

A first sensor for detecting the end of a sheet passing through the sheet introduction guide, a second sensor for detecting a front end of the sheet passing through the sheet discharge guide, and a first sensor.
And a control device for switching the reversing roller between normal and reverse based on the detection information from the sensor and the second sensor.

[0011] Further, the curving roller is positioned in the sheet reversing drum on the downstream side in the forward direction of the sheet due to the normal rotation of the reversing roller and urges the sheet being forwardly fed around the outer peripheral surface of the reversing roller. May be further provided.

On the other hand, the sheet introduction guide is connected to a linear sheet conveyance path, and the sheet discharge guide is connected to the sheet conveyance path downstream of the connection between the sheet introduction guide and the sheet conveyance path. It may be something. In this case, a front end portion is provided so as to be able to move forward or backward with respect to the sheet conveyance path, and further includes a sheet introduction plate for guiding a sheet conveyed along the sheet conveyance path to a sheet introduction guide. The sheet conveying path may be for guiding a sheet after copying by a copying machine to a sheet discharge tray.

When a sheet introduction plate is provided, the sheet being conveyed in the sheet conveyance path may be introduced into the sheet reversing device only when the sheet needs to be reversed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the sheet reversing device according to the present invention is incorporated in a transport path of a sorter attached to a copying machine will be described.
This will be described in detail with reference to FIGS.

As shown in FIG. 2, which shows a schematic structure of a sorter incorporating a sheet reversing device, a sorter 10 attached to a copying machine (not shown) is provided with a multi-stage sheet tray 11 for copying paper P sent from the copying machine. A sheet conveying path 12 for conveying the sheet to the side is formed. At the end of the sheet conveying path 12 on the copying machine side, the sheet tray 1 of the sheet conveying path 12
A pair of sheet carry-in rollers 13 to be sent to an end on one side are rotatably provided. The sheet transport path 12
A pair of sheet unloading rollers 14 for holding the copy sheet P and sending it out onto the sheet tray 11 are rotatably provided at an end of the sheet tray 11 on the side of the sheet tray 11.

The multi-stage sheet tray 11 is driven up and down via an elevating device (not shown) in conjunction with the operation of discharging the copy sheet P from the sheet discharge roller 14, and the copy sheets P are sorted on a predetermined sheet tray 11. It is to be sequentially loaded in a state of being placed.

A sheet reversing device 15 according to the present embodiment is incorporated in the middle of the above-described sheet conveying path 12, and the copy paper P sent from the copying machine to the sheet conveying path 12 is turned upside down as necessary. In this state, the sheet can be carried out to the sheet tray 11 side.

As shown in FIG. 2 and FIG. 1 showing a schematic structure of the sheet reversing device 15 in the present embodiment, the inner peripheral surface of the sheet reversing device 15 in the present embodiment is a guide surface 16 of the copy sheet P. Cylindrical sheet reversing drum 17
An upper sheet introduction guide 18 and a lower sheet introduction guide 19 for introducing the copy sheet P into the sheet reversing drum 17 from outside the sheet reversing drum 17;
The copy sheet P, which is provided near the inner peripheral surface of the sheet reversing drum 17 and is rotatable in the normal and reverse directions within the sheet reversing drum 17, and inverts the copy sheet P carried into the sheet reversing drum 17 from the upper and lower sheet introduction guides 18 and 19. Forward feeding (right rotation in FIG. 1) or reverse feeding (left rotation in FIG. 1) in the drum 17
The reversing roller 20 is connected to the sheet transport path 12 on the downstream side of the sheet transport path 12 from the connection portion between the lower sheet introduction guide 19 and the sheet transport path 12. P to sheet reversal drum 17
A sheet discharge guide 21 for feeding the sheet P to the outside, a pair of driven rotating discharge rollers 22 for nipping and feeding the copy sheet P conveyed in the sheet reversing drum 17 to the sheet discharge guide 21, and a reversing roller 20. The sheet reversal drum 17 on the downstream side in the forward direction of the copy sheet P due to the forward rotation
And a curved sheet urging guide 23 urged so that the copy sheet P being sequentially fed is wound around the outer peripheral surface of the reversing roller 20.

The sheet reversing drum 17 is used for copying paper P
It is designed to bend along the guide surface 16 by utilizing its own elastic force (so-called paper waist). By setting the inner diameter to, for example, about 130 mm to 140 mm, the A4 or A3 size A sheet of a size can be stored.

The upper sheet introduction guide 18 penetrates a sheet introduction port 24 formed on the outer periphery of the sheet reversing drum 17 and is inclined in a tangential direction of the sheet reversing drum 17. At the upper end of the upper sheet introduction guide 18, a first sheet detection sensor 25 for detecting the presence or absence of a copy sheet P passing over the upper sheet introduction guide 18 is provided. The lower sheet introduction guide 19 has an introduction position indicated by a two-dot chain line in FIG.
In FIG. 1, the lower end can be switched to a retracted position indicated by a solid line in which the lower end is retracted from the sheet conveying path 12.

Accordingly, when the lower sheet introduction guide 19 is at the introduction position by the actuator, the leading end of the copy sheet P drawn into the sheet conveying path 12 by the sheet carry-in roller 13 comes into contact with the lower sheet introduction guide 19. The sheet is fed from the upper sheet introduction guide 18 into the sheet reversing drum 17.

The reversing roller 20 is provided above the sheet reversing drum 17 with a gap of 4 to 5 mm from the inner peripheral surface of the sheet reversing drum 17. The sheet urging guide 23 is located on the opposite side of the upper sheet introduction guide 18 with the reversing roller 20 interposed therebetween.
In the present embodiment, they are formed of two plate members each having a waveform.

A sheet discharge port 26 is formed on the outer periphery of the sheet reversing drum 17 on the opposite side of the sheet introduction port 24 with the upper sheet introduction guide 18 interposed therebetween. One end is connected. The sheet discharge guide 21 is provided with a sheet discharge port 26.
, And is inclined in the tangential direction of the sheet reversing drum 17, further curved in an arc shape, and the other end is connected to the sheet conveying path 12. The discharge roller 22 is provided at one end of the sheet discharge guide 21 and transfers the copy paper P in the sheet reversing drum 17 from the sheet discharge guide 21 to the sheet transport path 12.
To return to. Further, a second sheet detection sensor 27 for detecting the presence or absence of the copy sheet P passing through the sheet discharge guide 21 is provided in the middle of the sheet discharge guide 21.

At the upper end of the upper sheet introduction guide 18, there is provided a discharge guide for folding the copy sheet P in the sheet reversing drum 17 between the pair of discharge rollers 22 by being folded back toward the discharge roller 22. A plate 28 is provided.

The above-mentioned two sheet detection sensors 25, 2
The detection signal 7 is output to a control device (not shown) that controls the operation of the actuator of the lower sheet introduction guide 19, the forward / reverse rotation of the reversing roller 20, and the driving of the discharge roller 22. Here, when a reversal processing signal of the copy sheet P is input to the control device, the control device operates the sheet reversing device 15 in a procedure described below.

FIGS. 3 to 5 show the state of conveyance of the copy sheet P by the sheet reversing device 15, and FIG. That is, it is determined in step S1 whether there is a copy paper P reversal command. If it is determined that there is a copy paper P reversal command, the process proceeds to step S2 and the lower sheet introduction guide 19 By operating the actuator, the lower end of the lower introduction guide 19 is moved forward, that is, shifted to the introduction position. Then, it is determined in step S3 whether the first sheet detection sensor 25 is on.

In step S3, the first sheet detection sensor 25 is not turned on, that is, the copy sheet P is fed into the lower guide 19 and the upper guide 18 from the sheet conveyance path 12 by the sheet carry-in roller 13. If it is determined that the copy sheet P is not turned on, the step of S3 is performed until the first sheet detection sensor 25 is turned on, that is, until it is determined that the copy sheet P has been fed into the lower guide 19 and the upper guide 18. repeat. Then, in step S4, the reversing roller 20 is rotated forward, and it is determined whether the first sheet detection sensor 25 is turned off.

As described above, when the copy sheet P is fed into the sheet reversing drum 17 from the upper guide 18, the leading end thereof is bent toward the reversing roller 20 by contacting the guide surface 16 of the sheet reversing drum 17. 1, the reversing roller 20 is provided by the sheet urging guide 23 located on the upper side.
, And is sequentially fed in the sheet reversing drum 17 by the normal rotation of the reversing roller 20.

If it is determined in step S4 that the first sheet detection sensor 25 has not been turned off, that is, if the rear end of the copy sheet P is located at the upper introduction guide 18, the first sheet is detected. Until the detection sensor 25 is turned off,
That is, until the leading edge of the copy sheet P is determined to be in contact with the guide surface 16 of the sheet reversing drum 17 as shown in FIG.
Repeat step 4. Then, in step S5, the reversing roller 20 is rotated in the reverse direction, and the driving of the discharge roller 22 is started.

By the reversing drive of the reversing roller 20, the copy sheet P in the sheet reversing drum 17 abutting on the reversing roller 20 is switched to the reversing state and fed between the discharge rollers 22, where it is pinched by the discharge rollers 22. In this state, the sheet is sent to the sheet discharge guide 21 side, and the second sheet detection sensor 27 is turned on, that is, the passage of the copy sheet P is detected.

On the other hand, during this time, a new copy sheet P is fed from the sheet conveying path 12 by the sheet feed roller 13 to the lower guide 19 and the upper guide 1 as shown in FIG.
8 is sent. Then, in step S7, the second
It is determined whether or not the sheet detection sensor 27 is turned off.

During this time, the leading edge of the new copy paper P is
Of the reversing roller 2
0 is turned forward again, but at this time, the copy paper P carried out to the sheet discharge guide 21 side is
2 and a gap of about 4 to 5 mm is formed between the guide surface 16 of the sheet reversing drum 17 and the reversing roller 20, so that the copy sheet P is switched to the forward feeding state. No trouble occurs. When the new copy sheet P is further fed into the sheet reversing drum 17, the sheet P is brought into contact with the copy sheet P being reversely fed and is bent toward the reversing roller 20, so that the sheet urging guide located on the upper side in FIG. 2
The sheet 3 is pressed against the reversing roller 20 and starts to be fed in the sheet reversing drum 17 by the normal rotation of the reversing roller 20 as shown in FIG.

In step S7, the second sheet detection sensor 27 has not been switched off, that is, the terminal of the copy sheet P returned from the sheet discharge guide 21 to the sheet conveying path 12 in the inverted state is the second sheet. If it is determined that the sheet has not passed through the detection sensor 27, the process proceeds to S until the second sheet detection sensor 27 is turned off, that is, until the terminal of the copy sheet P has passed through the second sheet detection sensor 27.
Step 7 is repeated. Then, the process proceeds to step S8 to stop the drive rotation of the discharge roller 22, and returns to the step S1 again to determine whether or not there is a command to invert the copy sheet P.

In this way, the copy sheet P carried in from the sheet conveying path 12 is continuously inverted and returned to the sheet conveying path 12 again, and is stacked on the sheet tray 11 by the sheet discharging rollers 14. You.

If it is determined in step S1 that the reversal command of the copy sheet P has been released, the flow proceeds to step S9 to operate the actuator to return the lower introduction guide 19 to the retracted position shown in FIG. Further, in step S10, the operation of the reversing roller 20 is stopped. In this case, the copy sheet P carried into the sheet conveyance path 12 by the sheet carry-in roller 13 is stacked on the sheet tray 11 from the sheet carry-out roller 14 without being sent to the sheet reversing device 15 side.

In the above-described embodiment, the process of stopping the discharge roller 22 is performed in step S8. However, the drive or stop of the discharge roller 22 may be controlled in accordance with the reversal command in step S1. Good.

In this embodiment, the sheet reversing device 15 is incorporated in the sheet conveying path 12 of the sorter 10 attached to the copying machine. However, it is naturally possible to incorporate the sheet reversing device 15 in the sheet conveying system of other various devices. .

[0038]

According to the sheet reversing device of the present invention, the sheet is guided into the sheet reversing drum, and the sheet is switched between forward and backward by using the reversing roller that rotates forward and backward in the sheet reversing drum. Even if a sheet exists in the sheet reversing drum, a new sheet can be fed into the sheet reversing drum to perform a continuous sheet reversing process.

[Brief description of the drawings]

FIG. 1 is a conceptual view of a mechanism showing a schematic structure of an embodiment of a sheet reversing device according to the present invention.

FIG. 2 is a conceptual diagram showing a schematic structure of an embodiment in which the sheet reversing device shown in FIG. 1 is incorporated in a conveyance system of a copying machine.

3 is an operation conceptual diagram showing an operation principle of the sheet reversing device shown in FIG. 1 together with FIGS. 4 and 5;

4 is an operation conceptual diagram showing an operation principle of the sheet reversing device shown in FIG. 1 together with FIGS. 3 and 5;

FIG. 5 is an operation conceptual diagram showing an operation principle of the sheet reversing device shown in FIG. 1 together with FIGS. 3 and 4;

FIG. 6 is a flowchart of the embodiment shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Sorter 11 Sheet tray 12 Sheet conveyance path 13 Sheet carrying-in roller 14 Sheet carrying-out roller 15 Sheet reversing device 16 Guide surface 17 Sheet reversing drum 18 Upper sheet introducing guide 19 Lower sheet introducing guide 20 Reversing roller 21 Sheet discharging guide 22 Discharge roller 23 Sheet Urging guide 24 sheet introduction port 25 first sheet detection sensor 26 sheet discharge port 27 second sheet detection sensor 28 discharge guide plate P copy paper

Claims (8)

[Claims] 1. A sheet reversing drum having a cylindrical shape with an inner peripheral surface serving as a sheet guiding surface; a sheet introduction guide for introducing a sheet into the sheet reversing drum from outside the sheet reversing drum; The sheet reversing drum is provided in the sheet reversing drum in the vicinity of the inner peripheral surface of the sheet reversing drum so as to be freely rotatable forward and backward, and the sheet conveyed from the sheet introduction guide into the sheet reversing drum is fed forward in the sheet reversing drum or A reversing roller for reversing the sheet, a sheet discharge guide for feeding a sheet reversed in the sheet reversing drum to the outside of the sheet reversing drum, and a sheet discharging guide for reversing the sheet conveyed in the sheet reversing drum. A sheet reversing device comprising a driving and rotating discharge roller for feeding the sheet to a sheet. 2. The sheet reversing device according to claim 1, wherein a peripheral length of an inner peripheral surface of the sheet reversing drum is set longer than a length along a sheet conveying direction. 3. The apparatus according to claim 1, wherein a gap between an inner peripheral surface of the sheet reversing drum and the reversing roller is set to be larger than twice a sheet thickness. The sheet reversing device according to the above. 4. A first sensor for detecting an end of a sheet passing through the sheet introduction guide, a second sensor for detecting a front end of a sheet passing through the sheet discharge guide, the first sensor and the first sensor. The sheet reversing device according to any one of claims 1 to 3, further comprising: a control device that switches between normal and reverse rotations of the reversing roller based on detection information from a second sensor. 5. A sheet which is positioned in the sheet reversing drum on the downstream side of the reversing roller in the forward direction of the sheet due to normal rotation so that the sheet being forward-conveyed is wound around the outer peripheral surface of the reversing roller. The sheet reversing device according to any one of claims 1 to 4, further comprising a curved sheet urging guide for urging. 6. The sheet introduction guide is connected to a linear sheet conveyance path, and the sheet discharge guide is connected to the sheet conveyance path downstream of a connection portion between the sheet introduction guide and the sheet conveyance path. The sheet reversing device according to any one of claims 1 to 5, wherein the sheet reversing device is connected to a sheet conveying path. 7. A sheet introduction plate, wherein a leading end portion of the sheet introduction path is provided so as to be able to move forward or backward with respect to the sheet conveyance path, and guides a sheet conveyed along the sheet conveyance path to the sheet introduction guide. The sheet reversing device according to claim 6, wherein: 8. The sheet reversing device according to claim 6, wherein the sheet conveying path is for guiding a sheet copied by a copying machine to a sheet discharge tray.