JPH0977323A - Paper sheet reversing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To speed-up reversing treatment by separating a pair of reversing rolls at a prescribed time after the paper sheet end of a paper sheet contacts an inserting roll, wherein a carrying direction of a paper sheet is reversed by a reversing roll. SOLUTION: In a paper sheet reversing device 14 provided between the fixed part and discharge part of a copying machine, a picture image recorded paper sheet is fed to a feeding-in passage 17 from a discharge 16 to be fed into a reversing 25 by a feeding-in roll composed of driven and driving rolls 19A and 19B. At that time, the paper sheet expandingly passes a shielding plate 30 at the tip of the paper sheet to be fed to normal/reverse roll 21 and pinch roll 22 to be led into a lead-in part 25A. After that, the paper sheet is fed in a reverse direction by the reversal of the normal/reverse roll 21 and pinch roll 22; and when the paper sheet tip is detected by a sensor arranged in the vicinity of feeding-out rollers 19a and 19b, a solenoid 24 is exited to separate the normal/reveres roll 21 and pinch roll 22 via a link 23 and nipping the paper sheet is released.

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, and more particularly to a sheet reversing device capable of increasing the reversal processing speed.

[0002]

2. Description of the Related Art In recent image recording apparatuses, particularly in multifunction machines such as copiers and printers, there is a desire to select the direction of the image recording surface of the discharged paper, so that the distance between the image recording section and the discharge section is large. The number of paper reversing devices arranged is increasing.

The conventional sheet reversing device is provided with a pair of feed rolls for feeding the sheet to the reversing section for reversing the conveying direction of the image-recorded sheet conveyed from the image recording section, and a rotation provided in the reversing section. Consists of a pair of reversing rolls for reversing the conveying direction of the sheet fed by the feeding roll by reversing the direction and a pair of feeding rolls for feeding the sheet of which the conveying direction is reversed from the reversing unit. Has been done.

In the sheet reversing device having the above structure, when the image-recorded sheet is fed to the reversing unit by the feeding roll, the reversing roll of the reversing unit takes in the fed sheet.
After a predetermined time, the reversing roll reverses the rotation direction to reverse the paper conveyance direction, and guides the paper whose conveyance direction has been reversed to the delivery roll. The feed roll feeds the paper, the conveyance direction of which is reversed, from the reversing unit to the discharge direction. Further, when a plurality of sheets are continuously reversed, the preceding sheet that has been reversed by the reversing unit is completely delivered by the delivery roll, and the trailing sheet is then fed to the reversing unit.

[0005]

However, according to the conventional paper reversing device, the succeeding paper cannot be fed into the reversing unit unless the preceding paper which has been reversed by the reversing unit by the feeding roll is completely fed. There is a limit to the speed of processing.

Therefore, an object of the present invention is to provide a sheet reversing device capable of speeding up the reversing process.

[0007]

In view of the above problems, the present invention has a pair of feeding rolls for feeding a sheet to a reversing unit for reversing the sheet conveying direction in order to speed up the reversing process.
A pair of reversing rolls provided in the reversing unit for reversing the rotation direction to reverse the conveying direction of the sheet fed by the feeding roll, and a pair of reversing unit for feeding the sheet whose conveyance direction is reversed from the reversing unit. Provided is a paper reversing device having a delivery roll and a control means for separating a pair of reversing rolls when a predetermined time has elapsed after the paper edge of the paper whose conveyance direction has been reversed by the reversing roll comes into contact with the delivery roll. It is a thing.

The pair of reversing rolls are provided on the first and second drive shafts that rotate by receiving a driving force,
It is preferable that the control means displace at least one of the first and second drive shafts to separate the pair of reversing rolls. Further, the first and second drive shafts are configured to receive a driving force from a common drive source by being connected to each other by meshing of gears provided at respective one ends, and the control means is It is preferable that the other end of at least one of the drive shafts is displaced to separate the pair of reversing rolls while keeping the gear meshing.

Further, in the construction of the above-mentioned paper reversing device, it is arranged at the intersection of the downstream conveying path of the feeding roll and the upstream conveying path of the feeding roll, and is fed when the paper is fed to the reversing portion by the feeding roll. Opening the downstream transport path of the roll and sending out the paper whose transport direction has been reversed by the reversing roll. Blocking the downstream transport path of the feeding roll, feeding the paper to the reversing part by the feeding roll and reversing roll. A shield plate may be provided between the fed-in paper and the fed-out paper to reduce the contact resistance between the two when the papers whose conveyance directions are reversed are simultaneously fed out. If you try to speed up the reversing process by feeding the trailing paper into the reversing unit while the preceding paper remains in the reversing unit, the conveyance resistance increases due to the friction resistance of the trailing paper of the preceding paper. If there is a risk of jams or scratches between paper sheets, or if the reversal timing, nip timing, release timing, etc. that determine the paper passage timing are not made strict, the preceding paper and trailing paper or the paper and roll may collide. Although a paper jam may occur, such a concern can be eliminated by providing the shield plate.

Further, in the above-described paper reversing device, a first drive transmission system for transmitting the driving force of the motor to the pair of reversing rolls via the electromagnetic clutch, and a pair of the driving force of the motor via the torque limiter. A reversing roll driving force transmitting means including a second drive transmission system for transmitting to the reversing roll may be provided.

In the sheet reversing device of the present invention having such a structure, the sheet is fed to the reversing section by the feeding roll,
By reversing the rotation direction of the reversing roll of the reversing unit, the conveying direction of the sheet fed into the reversing unit is reversed. Then, when a predetermined time elapses after the sheet edge of the sheet subjected to the reversing process contacts the delivery roll, the control unit separates the pair of reversing rolls, and the sheet subjected to the reversing process remains in the reversing unit. While the work is in progress, the nip between the pair of reversing rolls is released. At this time, when a plurality of paper sheets are continuously inverted, the next paper sheet is fed to the reversing section by a feed roll,
The sheet, which is nipped by the delivery roll and whose conveyance direction is reversed, is fed from the reversing unit, and the conveyance direction of the next sheet fed to the reversing unit is reversed by the reversing roll.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a sheet reversing device of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the configuration of a copying machine equipped with a sheet reversing device as an example of the present invention. This copier uses an image input unit (IIT: Imag
e Input Terminal) 1, a laser scanning unit 2 that emits two laser beams modulated according to the original image input by the image input unit 1, and guides the laser beams to predetermined exposure areas of the photoconductor drum 3, respectively. A photoconductor drum 3 that forms an electrostatic latent image by light exposure, and a charger 4 that charges the photoconductor drum 3.
A developing unit 5 or 6 for developing the electrostatic latent image formed on the photoconductor drum 3 with toner; and a transfer unit 7 for transferring the toner image on the photoconductor drum 3 onto a sheet supplied from a sheet storage unit 9. ,
A cleaning device 8 for removing the toner remaining on the photosensitive drum 3, a paper storage unit 9 for storing recording paper, a paper feed unit 10 for feeding the paper in the paper storage unit 9, and the paper at a predetermined timing. Register roll 11 sent to the transfer unit 7
A suction conveyance section 12 that conveys the transferred sheet while adsorbing it, a fixing section 13 that fixes the transfer image of the sheet, and a sheet reversing device 14 provided between the fixing section 13 and the discharge section 15.
And a double-sided / multi-recording passage 26 for feeding the sheet to the photosensitive drum 3 via the sheet reversing device 14.

The structure of the sheet reversing device 14 will be described with reference to FIG.

The sheet reversing device 14 includes a discharge path 16 for guiding the sheet on which the transfer image has been fixed to the discharge section 15, and a pull-in section 25.
A reversing passage 25 having an A and reversing the conveying direction of the fixed sheet in the discharge passage 16 and then guiding it to the discharging portion 15, and a feeding passage for feeding the fixed sheet from the discharging passage 16 to the reversing passage 25. 17, a delivery passage 18 for delivering the paper whose conveyance direction has been inverted in the inversion passage 25 to the discharge passage 16, a drive roll 19B arranged between the input passage 17 and the delivery passage 18, and arranged on both sides thereof. Driven roll 19A,
A triroll 19 forming a feed roll and a feed roll in the feed passage 17 and the feed passage 18, respectively, by 19C;
Double-sided / multiple recording path 26 for paper in the reverse path 25
To the route for sending to the feed route and the route for feeding to the pull-in unit 25A, and the sheet fed into the reversing passage 25 is pulled into the pull-in unit 25A, and when pulled for a predetermined length, it is inverted and the direction in which the pulled-in sheet is conveyed. The forward / reverse roll 21 for reversing, the pinch roll 22 elastically contacting the forward / reverse roll 21, the pinch roll 22 is supported, and the link 23 that rotates around the fulcrum 23A and the plunger 24A are projected and retracted. , A solenoid 24 that separates the pinch roll 22 from and into the forward / reverse roll 21 via a link 23, and a route that is provided between the feeding passage 17 and the discharging passage 16 and sends the fixed sheet as it is to the discharging portion 15. And a switching member 27 for switching to a route for performing reversal processing in the reversing passage 25 and then sending to the discharge unit 15, and rotating the switching member 27 via an arm 29. And that the solenoid 28, the delivery passage 1
7. A shield plate 30 is provided elastically at the intersection of 7 and the delivery passage 18 to close the connection port of the delivery passage 17, and the lead-in portion 25A is elastic at the branch point of the lead-in portion 25A and the double-sided / multiple recording passage 26. It is configured by including a shield plate 31 that is closed.

The shield plate 30 is made of a flexible PET film, and when the paper is fed from the feeding passage 17 into the reversing passage 25, it is spread by the tip of the paper,
When the sheet is sent from the reversing passage 25 to the sending passage 18 by opening the passage opening of the feeding passage 17, the passage opening of the feeding passage 17 is closed and the paper is sent from the feeding passage 17 to the reversing passage 25. When the sheet is sent from the reversing path 25 to the sending path 18, it is positioned between the two sheets to reduce the contact resistance between the two. When the passage opening of the sending path 17 is opened. The tip portion has at least a length below the intersection of the feed passage 17 and the feed passage 18, that is, inside the reversing passage 25.

The solenoid 24 is controlled by a control device (not shown), and when the sheet subjected to the reversing process in the reversing passage 25 is nipped by the feeding roll composed of the driving roll 19B and the driven roll 19C, the plunger 24A is retracted, The pinch roll 22 is displaced via the link 23, that is, the paper nip between the forward / reverse roll 21 and the pinch roll 22 is released.

Next, the structure of the drive transmission mechanism of the forward / reverse roll 21 and the pinch roll 22 will be described with reference to FIGS. 3 and 4.

Forward / reverse roll 21 and pinch roll 22
Of the drive transmission mechanism is rotatably supported by bearings provided in a housing or the like, and has rotating shafts 21A and 22A having forward and reverse rotation rolls 21 and pinch rolls 22 on the shafts, and rotating shafts 21A and 22A.
Gears 37, 38 provided at one end of the
Inversion electromagnetic clutch 3 provided at one end of the rotating shaft 21A
5, the forward rotation electromagnetic clutch 36, the gears 35A and 36A provided on the input sides of the reversing and forward rotation electromagnetic clutches 35 and 36, and the rotation shaft 54 parallel to the rotation shaft 21, which will be described later. Gear 34 meshing with gear 33
A and an idler gear 34 having a gear 34B meshing with the gear 36A, and attached to the rotation shaft of the motor 32,
The gear 35A and the gear 33 that meshes with the gear 34A of the idler gear 34 are provided.

The rotary shaft 22A is pressed by the elastic member 22B so that the pinch roll 22 is in pressure contact with the forward / reverse roll 21, and the rotation of the link 23 provided at the opposite end of the gear 38 causes the gear 38 to rotate. It is configured to be displaced by a predetermined length (about 8 mm) in the arrow direction with the meshing of 37 and 38 held.

The reversing electromagnetic clutch 35 is turned off during normal rotation to slip the gear 35A and the rotary shaft 21A, and is turned on during reversal to engage the gear 35A and the rotary shaft 21A. . On the other hand, the forward rotation electromagnetic clutch 36 is turned on at the time of forward rotation, and the gear 36A and the rotary shaft 2 are rotated.
1A is engaged, and the gear 36 is turned on when reversing.
A and the rotary shaft 21A are slippery. Therefore, during normal rotation, the drive torque of the motor 32 changes to the gear 33,
The torque is transmitted to the rotary shaft 21A via the idler gear 34 and the gear 36A, and the drive torque of the motor 32 is transmitted to the rotary shaft 21A via the gear 33 and the gear 35A when reversing.

The operation of the paper reversing device 14 will be described below with reference to FIG.
The explanation will be given with reference to (a), (b), (c), and (d). In the following operation, face-down printing, that is, a case in which the paper is reversed and the image recording surface is the back side will be described.

First, when a face-down printing mode is designated from an operation panel (not shown) and then a copy start command is given, the switching member 27 reverses the discharge route of the image-recorded paper in the reverse passage 25. To a discharge route to the discharge unit 15, and a drive mechanism (not shown) rotates the drive roll 19B counterclockwise. Further, the forward / reverse roll 21 and the pinch roll 22 are rotated in a predetermined direction by the drive transmission mechanism shown in FIGS. 3 and 4. That is, the motor 32 is driven and the reversing electromagnetic clutch 35 is turned off so that the gear 35A and the rotating shaft 21A slip idle, and the forward rotating electromagnetic clutch 36 is turned on to connect the gear 36A and the rotating shaft 21. The rotation shaft 21A is rotated by engaging and transmitting the driving torque of the motor 32 from the gear 33 to the gear 36A via the idler gear 34, and the rotation shaft 22A is rotated by the meshing of the gears 37 and 38.

On the other hand, the paper is fed from the paper accommodating portion 9 by the paper feeding unit 10, the toner image on the photosensitive drum 3 is transferred at the transfer portion 7, and the transferred image is fixed at the fixing portion 13. The paper on which the image has been fixed has been discharged into the discharge passage 16
Is sent to the inflow passage 17, and as shown in FIG.
The paper 55A is fed into the reversing path 25 by a feed roll including a driven roll 19A and a drive roll 19B.

When the front end of the paper 55A reaches the reversing passage 25, the front end of the paper 55A pushes the shield plate 30 to pass through the reversing passage 25 as shown in FIG. , And the pinch roll 22. The forward / reverse roll 21 and the pinch roll 22 pull the paper 55A into the pull-in portion 25A by rotating in a predetermined direction, and the rear end of the paper 55A is detected by a sensor (not shown) provided in the reverse passage 25, that is, the reverse passage. Two
When the trailing edge of the sheet 55A reaches the position where the trailing edge of the sheet 55A can be sent to the delivery passage 18 from 5, the sheet is inverted.

That is, the forward rotation electromagnetic clutch 36 is turned off, the gear 36A and the rotary shaft 21A are slipped, and the reverse electromagnetic clutch 35 is turned on, so that the gear 35A and the rotary shaft 21 are engaged. The drive torque of the motor 32 is increased by the engagement of the gear 33 and the gear 35A with the rotation shaft 21A.
Is directly transmitted to the rotary shaft 21A to reversely rotate,
The rotation shaft 22A is also reversely rotated at the same time by the engagement of the gears 37 and 38.

Forward / reverse roll 21 and pinch roll 22
When the sheet is reversed, the sheet 55A is fed in the reverse path 25 in the reverse direction as shown in FIG. Then, when the sheet 55A reaches the confluence portion of the feed passage 17 and the feed passage 19, it comes into contact with the shield plate 30 again, but the shield plate 30 closes the passage port of the feed passage 17 due to the elastic force. The paper 55A is surely guided to the delivery passage 18.
Is sent to a delivery roll consisting of a drive roll 19A and a driven roll 19B.

The sheet 55A is conveyed to the delivery roll, and a sensor (not shown) arranged near the delivery roll detects the leading edge of the sheet 55A, that is, the delivery roll moves the sheet 5A.
When 5A is nipped, a control device (not shown) turns on the solenoid 24 to immerse the plunger 24A and rotate the link 23 to rotate the forward / reverse roll 21 and the pinch roll 2
2 is separated. As a result, the nip of the paper 55A formed by the forward / reverse roll 21 and the pinch roll 22 is released.

When the paper 55A is nipped by the delivery roll, the paper 55A is guided from the reversing passage 25 to the discharging portion 15 and discharged. Here, in the case of continuously reversing and ejecting the new image-recorded paper 55B, as shown in (d) of FIG. 5, the second paper 55B of the second paper 55B is discharged before the paper 55A is completely discharged. The tip spreads the shield plate 30 and has already entered the reversal passage 25. At this time, there are two sheets of paper in the reversing passage 25, but since the shield plate 30 is interposed between the two sheets of paper 55A, 55B, the sheets of paper 55A, 55B.
The conveyance resistance can be suppressed to a magnitude caused by the frictional force between the sheets 55A and 55B and the shield plate 30, and the scraping noise of the sheets 55A and 55B can also be suppressed.

When the trailing edge of the paper 55B passes through the feeding roll, the solenoid 24 is turned off, and the forward / reverse roll 21 and the pinch roll 22 shift from the nip released state to the nip state. This time is the timing when the signal output from the sheet detection sensor (not shown) arranged on the discharge portion side of the feed roll to the control device is turned off. At this time, since the gears 37 and 38 attached to the ends of the rotation shafts 21A and 22A of the forward / reverse roll 21 and the pinch roll 22 are maintained in the nip released state, when the nip state is restored again, The surface speeds of the two rolls 21 and 22 are equal to each other, and no slip noise or skew is generated.

FIG. 6 shows the structure of a sheet reversing device according to the second embodiment of the present invention. This paper reversing device has 1
The electromagnetic clutch is used to switch the rotation direction of the rotary shaft 21A, and is provided on the rotary shaft 21A.
The forward rotation electromagnetic clutch 35 for turning on / off the transmission of the driving torque from the gear 35A to the rotary shaft 21A, and the rotary shaft 21A.
The gear 41 provided on the output side of the forward rotation electromagnetic clutch 35 and the gear 40A provided on the rotary shaft 54 parallel to the rotary shaft 21A and meshed with the gear 33 of the motor 32,
And a gear 40B meshed with the gear 41, gears 40A, 4
When the torque difference between 0B becomes larger than a predetermined value, the torque limiter 39 slips idly.

In the above structure, the forward rotation electromagnetic clutch 36 is turned on during the forward rotation, and the gear 36A and the rotary shaft 21 are rotated.
When A is fastened and the drive torque is transmitted to the rotary shaft 21A, the rotary shafts 21A and 22A are normally rotated. At this time,
Since the gears 40A and 40B rotate in different directions, the torque difference between the gears 40A and 40B increases, and the torque limiter 39 slips. On the other hand, when reversing, the forward electromagnetic clutch 36 is turned off and the gear 36A
Then, the rotary shaft 21A is slipped. In this state, the gear 4
Since the torque difference between 0A and 40B is smaller than a predetermined value, the torque limiter 39 transmits the drive torque input from the gear 40A to the gear 40B, and the drive torque is transmitted to the rotary shaft 21A via the gear 41. As a result, the rotary shafts 21A and 22A are reversed.

In such a configuration, the torque limiter 39
By using, the forward / reverse roll 21 and the pinch roll 22 can be switched between normal rotation and reverse rotation with one electromagnetic clutch, and the fear of switching between two electromagnetic clutches can be eliminated. That is, when two electromagnetic clutches are switched on and off to perform normal rotation and reverse rotation, if the switching time of the electromagnetic clutch is deviated, the following problems may occur. (1) When both clutches are turned on: There is a shift in the reversal timing due to paper stoppage, impact noise is generated, and drive transmission system damage occurs. (2) When both clutches are off The reversal timing is misaligned due to paper overrun.

7 (a) and 7 (b) show the structure of the sheet reversing device of the third embodiment of the present invention. This paper reversing device is provided with a motor 51 as driving means for the pinch roll 22.
And the drive shaft 52 of the motor 51 and the pulley 4 of the rotary shaft 22A.
9 has a drive belt 50 stretched around 9, and a gear 43 provided on the drive shaft of the motor 42 as a separating / contacting means for the pinch roll 22, and a cam drive rotating shaft 44A that meshes with the gear 43. Gear 44 to be driven and cam driving rotary shaft 4
4A and cam drive gears 45A and 45B provided on the rotary shaft 21A, and cam drive gears 45A and 45B provided on the rotary shaft 21A.
Cam driving gears 46A and 46B meshed with the cam driving gears 46A and 46B, and cams 47A and 47B that are integrated with the cam driving gears 46A and 46B and move the rotating shaft 22A in the direction opposite to the rotating shaft 21A by a predetermined amount of rotation; Flanges 48A and 48B provided on 47B and flanges 48A and 48B
To the rotation amount sensor 53 for detecting the rotation amounts of the cams 47A and 47B.

In the above structure, the rotary shaft 21A is driven by the motor 32, and the rotary shaft 22A is driven by the motor 51, so that the rotation directions of the forward / reverse roll 21 and the pinch roll 22 are switched at the same time. ing. Therefore, when switching the rotation direction, it is possible to prevent an increase in skew, a paper jam, and a misregistration of the lead registration of the paper. In addition, the rotation amount sensor 53
When the motor 42 rotates the cam driving rotary shaft 44A by a predetermined amount while detecting the amount of rotation of the flanges 48A and 48B with the cams 47A and 47B, the cams 47A and 47B press the rotary shaft 22A to move in the opposite direction to the rotary shaft 21A. For forward and reverse roll 2
1 and the pinch roll 22 can be separated and contacted.

[0036]

As described above, according to the sheet reversing device of the present invention, the pair of reversing rolls is moved when a predetermined time elapses after the sheet edge of the sheet whose conveyance direction is reversed contacts the delivery roll. It is configured to release the nip of the paper by separating it, and it is possible to feed new paper to the reversing unit while the paper subjected to the reversing process remains in the reversing unit, so high processing speed Can be realized.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of one embodiment of the present invention.

FIG. 2 is an enlarged view of the sheet reversing device in FIG.

FIG. 3 is an explanatory diagram showing a drive transmission mechanism according to one embodiment.

FIG. 4 is an explanatory diagram showing a drive transmission mechanism according to one embodiment.

FIG. 5 is an explanatory diagram showing a flow of sheets in the sheet reversing device according to the one example.

FIG. 6 is an explanatory diagram showing a second embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a third embodiment of the present invention.

[Explanation of symbols]

 1 Image Input Section 2 Laser Scanning Section 3 Photosensitive Drum 4 Charging Device 5 Developing Machine 6 Developing Machine 7 Transfer Section 8 Cleaning Device 9 Paper Storage Section 10 Paper Feeding Unit 11 Register Roll 12 Adsorption / Transportation Section 13 Fixing Section 14 Paper Reversing Device 15 Ejection Part 16 Discharge passage 17 Inlet passage 18 Outlet passage 19 Triroll 19A Drive roll 19B, 19C Driven roll 20 Switching member 21 Forward / reverse roll 21A Rotating shaft 22 Pinch roll 22A Rotating shaft 23 Link 24 Solenoid 24A Plunger 25 Reversing passage 25A Retracting part 26 double-sided / multiple recording path 27 switching member 28 solenoid 29 arm 30 shield plate 31 shield plate 32 motor 33 gear 34 idler gear 34A, 34B gear 35 reversing electromagnetic clutch 35A gear 36 forward rotating electromagnetic clutch 36A YA 37, 38 Gear 39 Torque limiter 40A, 40B Gear 41 Gear 42 Motor 43 Gear 44 Gear 44A Cam drive rotating shaft 45A, 45B Cam drive gear 46A, 46B Cam drive gear 47A, 47B Cam 48A, 48B Flange 49 Pulley 50 drive belt 51 motor 52 drive shaft 53 rotation amount sensor 54 rotation shaft

Claims (5)

[Claims] 1. A pair of feed rolls for feeding the paper to a reversing unit for reversing the conveyance direction of the paper; and a pair of feed rolls provided in the reversing unit for reversing the rotation direction to feed the paper. A pair of reversing rolls for reversing the conveyance direction of the sheet, a pair of delivery rolls for ejecting the sheet of which the conveyance direction is reversed from the reversing unit, and a reversing roll for the delivery roll to change the conveyance direction. A sheet reversing device, comprising: a control unit that separates the pair of reversing rolls when a predetermined time elapses after the sheet edges of the reversed sheet come into contact with each other. 2. The pair of reversing rolls are provided on first and second drive shafts that rotate by receiving a driving force, respectively, and the control means includes at least the first and second drive shafts. The sheet reversing device according to claim 1, wherein one drive shaft is displaced to separate the pair of reversing rolls. 3. The first and second drive shafts are configured to receive a driving force from a common drive source by being connected to each other by meshing gears provided at one ends thereof. 3. The sheet reversing device according to claim 2, wherein the control unit is configured to displace the other end of the at least one drive shaft to separate the pair of reversing rolls while keeping the gear meshing. 4. A pair of feeding rolls for feeding the paper to a reversing unit for reversing the conveying direction of the paper, and a pair of feeding rolls provided in the reversing unit for reversing the rotation direction to feed the paper. A pair of reversing rolls for reversing the conveyance direction of the sheet, a pair of delivery rolls for ejecting the sheet of which the conveyance direction is reversed from the reversing unit, and a reversing roll for the delivery roll to change the conveyance direction. Control means for separating the pair of reversing rolls when a predetermined time elapses after the sheet ends of the reversed sheets have come into contact with each other, a downstream conveyance path of the feed roll, and an upstream conveyance path of the delivery roll. When the sheet is fed to the reversing unit by the feeding roll, the downstream conveyance path of the feeding roll is opened, and the reversing roll is used to convey the sheet. When sending the reversed paper, the downstream conveying path of the feeding roll is closed, and the feeding direction of the paper is fed to the reversing unit by the feeding roll and the conveying direction is reversed by the reversing roll. A sheet reversing device, which is provided between the fed sheet and the fed sheet and reduces a contact resistance between the fed sheet and the fed sheet at the same time. 5. A pair of feed rolls for feeding the paper to a reversing unit for reversing the conveyance direction of the paper, and a pair of feed rolls provided in the reversing unit for reversing the rotation direction to feed the paper. A pair of reversing rolls for reversing the conveyance direction of the sheet, a pair of delivery rolls for ejecting the sheet of which the conveyance direction is reversed from the reversing unit, and a reversing roll for the delivery roll to change the conveyance direction. Control means for separating the pair of reversing rolls after a lapse of a predetermined time after contact of the sheet ends of the reversed sheets, and transmission of a driving force of a motor to the pair of reversing rolls via an electromagnetic clutch. A reversing roll driving force transmitting device including a first drive transmitting system and a second drive transmitting system for transmitting the driving force of the motor to the pair of reversing rolls via a torque limiter. Sheet reversing device, characterized in that it comprises.