JPH09227007A - Conveying device for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a good paper conveying property when paper sheets are discharged to the outside of a device and when paper sheets are conveyed to the next conveying process in the device. SOLUTION: A discharge roller 31 having a function to discharge paper sheets to a discharge tray and a function to invert paper sheets and feed them to the next conveying process in the double-face copying mode is constituted of the first and second rollers 51, 52. Roller bodies 54, 55 are fixed to the rollers 51, 52 at the uniform pitch on a roller shaft 53 respectively, and the second roller 52 is made movable in the axial direction. The corrugation application state that the roller bodies 54, 55 are arranged in turn and the corrugation nonapplication state that they are kept in contact with each other can be switched by a solenoid 60. When paper sheets are discharged, this conveying device is set to the corrugation application state so that corrugation is applied to paper sheets. When paper sheets are fed to a double-face copying unit in the double-face copying mode, the device is switched to the corrugation nonapplication state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an electrophotographic process such as a copying machine and a printer,
More specifically, the present invention relates to a conveying device including a pair of rollers for conveying an image-formed sheet inside the apparatus or discharging the sheet outside the apparatus.

[0002]

2. Description of the Related Art In general, an image forming apparatus such as a copying machine utilizing an electrophotographic process supplies sheets of paper one by one to an image forming means from a paper feed tray in which a large number of sheets are stacked and accommodated. The forming unit forms an image based on the input image signal on a sheet and then ejects the sheet to the outside of the apparatus. Further, in recent years, a copying machine provided with a double-sided copying function for automatically and sequentially forming images on the front and back surfaces of a sheet has been provided. This is because the sheet on which the image is formed on the first surface by the image forming unit is conveyed through the circulation conveyance path, the sheet is reversed in the middle of the circulation conveyance path, and then the sheet is fed again to the image formation section. The image is formed on the second surface.

In such a double-sided copying function, a method of switching back the paper is adopted when reversing the paper. This switchback path is generally provided inside the device, but for the purpose of downsizing the device, the trailing end of the paper is placed on the discharge tray that discharges the paper out of the device in the case of normal single-sided copying. There is provided a copying machine of a type in which the sheet is temporarily discharged while being held, and then the sheet is circulated with the trailing end of the sheet being the leading end. In other words, by sharing the switchback route with the discharge route,
The device is being miniaturized.

In the paper conveying method in the apparatus, the paper is guided between a pair of rollers in which two rollers are opposed to each other, and the paper is sandwiched by a frictional force generated between the two rollers in a direction corresponding to the rotation direction of the roller pair. The method of transporting to is generally used. Here, in particular, in the case where a so-called corrugation roller is used as the discharge roller for discharging the paper to the outside of the apparatus, in order to prevent deterioration of the accommodation property in the discharge tray due to the curl (rolling tendency) remaining on the discharged paper. There are many. The corrugation roller is a roller that forms weak wavy streaks (hereinafter referred to as corrugations) that extend in the transport direction on the sheet as the sheet passes, thereby correcting curls and strengthening the so-called waist of the sheet. . For example, Japanese Unexamined Patent Publication No. 60-171963 discloses a corrugation roller in which corrugation is applied to a sheet of paper that passes by changing the widths of a plurality of roller bodies that are in contact with each other. There is also a corrugation roller that shifts the roller bodies of the respective rollers in the axial direction to make them non-contact with each other so that the pressure of the adjacent roller bodies is alternately applied vertically along the axial direction to impart corrugation.

[0005]

In the copying machine having the double-sided copying function of the type in which the paper discharge path is also used as the switchback path, when the paper is reversed, first the paper is discharged by the discharge roller. The sheet is once discharged onto the discharge tray until the discharge roller holds the rear end of the sheet, and then the discharge roller reverses and the sheet is sent to the conveying path for double-sided copying with the rear end of the sheet being the leading end.

Here, when the discharge roller is the corrugation roller, the above-mentioned corrugation has an effect on the discharge of the sheet, but when the sheet is fed to the conveying path for double-sided copying for reversing, the sheet is corrugated. Due to this, conveyance failure occurs. In other words, a plurality of ordinary roller pairs that convey the paper to the image forming unit again are arranged in the conveyance path, and when the corrugated paper is introduced into these roller pairs, the conveyance leading edge of the paper may break. As a result, corrugation is strengthened and wrinkles are caused as the paper passes, and the paper is damaged, or paper jams occur. If the paper is still damaged, it cannot be used even if an image is formed on the second surface. That is, the corrugation roller
This is effective when the paper is finally discharged out of the device and there is no subsequent transfer process, but if it is a passing point where the paper is continuously transferred inside the device, its action adversely affects the paper transfer. It was a thing.

The present invention has been made in view of the above circumstances, and both in the case of discharging a sheet outside the apparatus and in the case of carrying the sheet to the next carrying process in the apparatus,
An object of the present invention is to provide a conveyance device of an image forming apparatus that can realize good conveyance of sheets.

[0008]

The present invention has been made to achieve the above object, and has the following constitution as a solving means. A transport device of an image forming apparatus for transporting a transported object such as a sheet sandwiched between a pair of rollers in a direction according to a rotation direction of the pair of rollers, wherein a plurality of roller bodies are axially spaced from each other. A first roller provided and a second roller provided on the roller shaft with a plurality of roller bodies spaced apart in the axial direction, and arranged so as to face each other so that the roller bodies contact each other. A pair of rollers, and the first
Between at least one of the roller and the second roller, which is rotated in a direction corresponding to the transport direction of the transported body, and the roller body that is axially adjacent to the roller pair, It is characterized by further comprising: a corrugation imparting member that imparts corrugation to the transported object sandwiched by the roller pair; and a switching unit that switches the corrugation imparting member between a corrugation imparting state and a non-conveying state on the sheet. . In the above configuration, the transport mode of the transported object is divided into a discharge mode in which the transported object is discharged to the outside of the apparatus and a mid-transport mode in which the transported object is sent to the next transportation process in the apparatus. In this case, the control means is provided to control the switching means so that the corrugation imparting member moves to the imparted state, and in the mid-transport mode, the corrugation imparting member moves to the non- imparted state.

Further, in a conveying device of an image forming apparatus for conveying a conveyed object such as a sheet sandwiched between a pair of rollers in a direction according to a rotation direction of the pair of rollers, a plurality of roller bodies are arranged on a roller shaft in the axial direction. A first roller provided with a space therebetween, and a plurality of roller bodies provided on the roller shaft with a space in the axial direction, and arranged so as to be opposed to each other so that the respective roller bodies come into contact with the first roller. A pair of rollers including two rollers, a rotation driving unit that rotates at least one of the first roller and the second roller in a direction corresponding to the transport direction of the transported object, and the first roller. By relatively moving the first roller and the second roller in the axial direction, a corrugated state in which the roller body of the first roller is arranged between the roller bodies of the second roller, and the first roller. Of the roller body and the second roller It is characterized by comprising a switching means for switching to a non-applied state of the corrugation and the over La bodies in contact with each other. In the above configuration, the transport mode of the transported object is divided into a discharge mode in which the transported object is discharged to the outside of the apparatus and a mid-transport mode in which the transported object is sent to the next processing process in the apparatus. In this case, the control means controls the switching means so that the roller pair is in the corrugation-applied state and the roller pair is in the corrugation-non-applied state in the mid-transport mode.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. (1) First Embodiment (FIGS. 1 to 5) A. Configuration of the first embodiment A-1. Configuration of Copying Machine FIG. 1 shows a copying machine according to a first embodiment of the present invention. Reference numeral 1 in the figure denotes the apparatus main body. A double-sided copying unit 2 is detachably attached to one side surface (left side surface in FIG. 1) of the apparatus main body 1, and a document table (not shown) on which an original is placed and set is placed on the apparatus main body 1. It is provided. The document table is equipped with a reading device that optically reads an image of a document.

An image forming means 3 is provided in the apparatus main body 1. The image forming unit 3 includes a photosensitive drum 4
A memory 5 in which the image signal of the original read by the reading device is input and stored; and an image signal output from the memory 5 is input and the image signal is electrostatically transferred onto the photosensitive drum 4. Image writing means 6 formed as a latent image
And a developing device 7 that visualizes or develops the electrostatic latent image on the photosensitive drum 4 with a developer such as toner, and the image developed on the photosensitive drum 4 on a sheet (transport target) S. A transfer drum for transferring and a fixing device 10 including a fixing roller pair 9 for fixing the image transferred on the paper S on the paper S are provided.

The image forming means 3 in the apparatus body 1
A paper feed tray 11 in which a large number of paper sheets S are stacked and accommodated is removably inserted under. The paper feed tray 11 is designed to be attached to and detached from the front side (front side in the drawing) of the apparatus main body 1. From the paper feed tray 11,
By the paper feed roller group 15 including the nudger roller 12, the feed roller 13, and the retard roller 14,
The sheets S are supplied to the image forming means 3 one by one as follows.

The uppermost sheet S in the sheet feed tray 11
Is first drawn out by the najar roller 12 and then fed between the feed roller 13 and the retard roller 14, and is conveyed through the supply conveyance path 16 by both rollers 13 and 14 and guided to the registration roller 17. When two or more sheets S are pulled out by the najar roller 12 and fed in a double feed manner, the retard roller 14 rotates in a direction opposite to the conveying direction, so that the lower sheet S other than the uppermost sheet S is transferred to both rollers. It is possible to prevent the entry between 13 and 14. The conveyance timing and the conveyance posture of the sheet S that has reached the registration roller 17 are adjusted here, and then, the sheet S is fed between the photosensitive drum 4 and the transfer drum 8 of the image forming unit 3. The paper S is these drums 4,
After passing through the space between the rollers 8, the toner is fed between the roller pair 9 of the fixing device 10. The conveyance path of the paper S from the paper feed tray 11 to the fixing device 10 is from bottom to top, and the paper S that has passed through the fixing device 10 has its main path (guide member) 18 on the right and left sides. It can be switched to either one of the first and second conveyance paths 21 and 22 that branch into each. The first and second transport paths 21,
22 are connected by an inversion conveyance path 23 provided on the main gate 18. It should be noted that the apparatus main body 1 is provided with a return conveyance path 24 that opens to the left side surface and joins the supply conveyance path 16.

The sheet S guided to the first transport path 21 on the right side by the main gate 18 is discharged to the outside 1 of the apparatus main body by the first discharge roller 31 and is formed on the upper surface of the apparatus main body 1. It is stored on the discharge tray 41. The sheets S are stored on the first discharge tray 41 with the first surface on which the image is formed by the image forming unit 3 facing downward. Further, the sheet S guided by the main gate 18 to the second transport path 22 on the left side is sent to the double-sided copying unit 2 by the transport roller 25.

In the case of double-sided copying, the sheet S is guided to the first transport path 21 by the main gate 18 and once on the first discharge tray 41 with the rear end of the transport being held by the first discharge roller 31. To the main gate 18
Is switched and the first discharge roller 31 is rotated in the reverse direction so that the first discharge roller 31 is switched back to be reversed.
It is fed to the double-sided copying unit 2 by the transport roller 25.

The double-sided copying unit 2 has a relatively thin outer shell having a depth equivalent to that of the apparatus main body 1, and a hinge plate 33 integrally formed at the lower end portion is attached to the apparatus main body 1 via a horizontal pin 34. It is hinge-coupled and can be opened and closed left and right around the pin 34 as an axis. In the duplex copying unit 2, a hook (not shown) attached to the upper end portion is normally engaged with the apparatus main body 1 so that the set state facing the apparatus main body 1 is maintained.

In the double-sided copying unit 2, a circulation conveyance path 35 for receiving the paper S from the transport roller 25 and conveying the paper S to the return conveyance path 24 of the apparatus main body 1.
Are provided above and below. This circulation conveyance path 35
A plurality of transport rollers 36 for transporting the paper S are provided in the. A discharge conveyance path 37 that opens to the left side is branched from the upper part of the circulation conveyance path 35, and the circulation conveyance path 35 and the discharge conveyance path 3 are branched at the branch point.
A sub-gate 38 that switches the path of the paper S is provided on one of the seven sides. The sheet S guided by the sub-gate 38 to the discharge / conveyance path 37 is discharged to the outside by the second discharge roller 32, and is stored on the second discharge tray 42. When guided to the circulation conveyance path 35, the sheet S is conveyed through the circulation conveyance path 35 by the transport rollers 36 and enters the return conveyance path 24 to return to the apparatus main body 1.

A-2. Configuration of First Discharge Roller Next, the configuration of the first discharge roller 31 according to the present invention will be described. As shown in FIG. 2, the first discharge roller 31 includes a lower first roller 51 and an upper second roller 5.
2 is a so-called roller pair arranged so as to face each other. The first roller 51 has a plurality of (four in this case) roller bodies 54 coaxially fixed to a roller shaft 53 at equal intervals in the axial direction. On the other hand, the second roller 52 has the same structure, and a plurality of roller bodies 55 are coaxially fixed to the roller shaft 53 at equal intervals in the axial direction. Both roller bodies 54, 55 are adapted to come into contact with each other in correspondence with the location. The roller body 5 of the first roller 51
Although 4 is a mere columnar shape, the roller body 55 of the second roller 52 has a tapered portion 55b at one end of the cylindrical portion 55a.
Are formed. The axial length of the cylindrical portion 55a is the first
Is substantially the same as that of the roller body 54 of the roller 51 of
The columnar portion 55a can contact the roller body 54 of the first roller 51. The pitch of the roller bodies 54, 55 in each roller 51, 52 is equal, and the second roller 5
The axial length of the second roller body 55 is set shorter than the distance between the roller bodies 54 of the first roller 51. In addition,
The roller body 54 is formed of a material such as rubber having an appropriate elasticity capable of conveying the paper S, and the roller body 55 is formed of a resin such as polyacetal and contact with each other.

A driven gear 56 is fixed to one end of the roller shaft 53 of the first roller 51, and the driven gear 56 is fixed.
A drive gear 57, which is rotated by a rotation drive means such as a motor (not shown), is meshed therewith. Further, gears 58 meshing with each other are provided at both ends of the roller shaft 53 of each roller 51, 52.
When the drive gear 57 rotates, both rollers 51 and 52 are in the forward direction (rotational directions are opposite to each other).
It is designed to rotate.

Now, the first roller 51 and the second roller 5
Although the two roller bodies 54 and 55 are in contact with each other,
In the first discharge roller 31, the second roller 5
By moving 2 in the axial direction, the roller bodies 54, 55
The roller body 54 is axially contacted with each other.
The roller body 55 is arranged between the two so that it can be switched to a state where it does not contact. The switching is performed by a solenoid (switching means) 60.

The solenoid 60 has a conventionally well-known structure in which a plunger 62 is inserted into a solenoid body 61 so as to be movable back and forth, and is arranged in proximity to one end portion (the left end portion in FIG. 2) of the second roller 52. . The plunger 62 moves back and forth along the axial direction of the second roller 52, and the arm 6 is attached to the tip thereof.
3 is pin-coupled. A central portion of the arm 63 is supported by a pin 64 so as to be horizontally rotatable. On the other hand, at one end of the second roller 52, the circumferential groove 65a is formed.
A pulley-shaped collar 65 having is fixed, and the tip of the arm 63 is fitted in the circumferential groove 65a of the collar 65. A return spring 66 is hooked on the tip side of the pin 64 of the arm 63.

In this case, the plunger 62 retracts to the solenoid body 61 side when the solenoid 60 is energized, and advances by the force of the return spring 66 when deenergized. Then, in the case of normal non-energization, as shown in FIG. 2, the arm 63 moves the second roller 52 in the direction of the arrow a along the axial direction via the collar 65 by the force of the return spring 66. At this time, the second
The roller bodies 55 of the roller 52 of the first roller 51 are the same as the roller bodies 55 of the first roller 51 except for the roller body 55 on the front end side in the moving direction.
Located between 4 That is, the roller bodies 54 and 55 are arranged in a zigzag pattern in which they are alternately arranged in the vertical direction (see FIG. 3). In this case, it is preferable that the cylindrical portion 55a of the roller body 55 is located at the center between the roller bodies 54. next,
When the solenoid 60 is energized, the plunger 62 retreats against the force of the return spring 66 and the arm 63 moves toward the collar 65.
The second roller 52 is moved in the direction of arrow b along the axial direction via. Then, each roller body 55 of the second roller 52 elastically contacts the roller body 54 of the first roller 51 (see FIG. 4). Roller shaft 53 of each roller 51, 52
Is set so that the roller bodies 54, 55 elastically contact each other. Therefore, when the roller bodies 54, 55 are not in contact with each other as described above, the roller body 5
4, 55 slightly overlap in the direction orthogonal to the axial direction.

When the solenoid 60 is not energized, the roller body 5 is
When 4, 55 are in a staggered arrangement, this first discharge roller 31
Corrugation is applied to the sheet S passing through the sheet S by the pressure of the roller bodies 54 and 55 being alternately applied in the vertical direction along the width direction. The pressure applied to the paper S from the roller bodies 54 and 55 is determined by the amount of the above-mentioned overlap. On the other hand, the solenoid 60 is energized and the roller body 54,
When 55 are in contact with each other, corrugation is not applied to the paper S passing through the first discharge roller 31. As described above, in the first discharge roller 31, the solenoid 60 causes the roller bodies 54 and 55 shown in FIG. 3 to be in the non-contact corrugation state, and the rollers 54 and 55 shown in FIG. 4 to be in contact with each other. It can be switched to two states of the corrugation non-applied state.

Since the second discharge roller 32 is a roller that only discharges the paper S to the second discharge tray 41, it has a function of switching the application and non-application of corrugation like the first discharge roller 31. No corrugation roller is used to provide corrugation.

B. Operation of the First Embodiment The operation of the copying machine is controlled by the control means (not shown) including the solenoid 60 as follows. The control form is
It is roughly classified into a "single-sided copy mode", a "composite copy mode", and a "double-sided copy mode", and in either case, it is preselected whether to accommodate in the first discharge tray 41 or the second discharge tray 42. To do.

Single-sided copy mode The first discharge roller 31 is in a normal corrugation-applied state. One sheet S is conveyed from the sheet feed tray 11 by the sheet feed roller group 15 to the registration roller 17, and after the conveyance timing and the conveyance posture are adjusted by the roller 17, the sheet S is the photoconductor of the image forming unit 3. It is fed between the drum 4 and the transfer drum 8. While passing through the drums 4 and 8, the image developed on the photosensitive drum 4 is transferred to the first surface of the paper S. Next, the sheet S passes through the roller pair 9 of the fixing device 10, and the image transferred here is fixed.

After the fixing device 10, the first discharge tray 4 is provided.
When 1 is selected, the paper S is the main gate 18
Is guided to the first transport path 21 by the first discharge roller 3
The image is copied into the first discharge tray 41 with the first surface thereof facing downward. First discharge roller 3
Since 1 is in the corrugation-applied state, the paper S
Is corrugated, and the paper S is stored in the first discharge tray 41 while curling is suppressed. When the second discharge tray 42 is selected, the sheet S is guided by the main gate 18 to the transport roller 25 via the second transport path 22, and the roller 25 circulates and transports the duplex copying unit 2. Enter road 35. Next, the sheet S is guided by the sub-gate 38 from the discharge / conveyance path 37 to the second discharge roller 32, and is accommodated in the second discharge tray 42 by the second discharge roller 32 with the first surface thereof facing upward. . Since the second discharge roller 32 is a corrugation roller, corrugation is applied to the paper S, and the paper S is stored in the second discharge tray 42 while curling is suppressed.

Synthetic Copy Mode The first discharge roller 31 is in a normal corrugation imparting state. The sheet S having the image transferred onto the first surface of the sheet S and passing through the fixing device 10 is guided to the second transport path 22 by the main gate 18 and enters the circulation transport path 35 in the double-sided copying unit 2. Then, after being guided to the circulation conveyance path 35 by the sub-gate 38 and conveyed through the circulation conveyance path 35, it is sent to the return conveyance path 24 of the apparatus main body 1. Then, the transfer and fixing processes are performed again, so that a different image is formed on the first surface. After that, when the first discharge tray 41 is selected, the sheet S passes through the first transport path 21 by the main gate 18 and the first discharge roller 31 causes the first surface to face downward. It is stored in the discharge tray 41. When the second discharge tray 42 is selected, the sheet S is guided to the second transport path 22 by the main gate 18, and the transport roller 25
Is conveyed along the discharge conveyance path 37 by the second discharge roller 3
The second discharge tray 4 with the first side facing upward by 2
It is housed in 2.

Double-sided copying mode The first discharge roller 31 is in the corrugation non-applied state when the sheet is reversed, and in the corrugation provided state when the sheet is discharged. The sheet S having the image transferred onto the first surface and having passed through the fixing device 10 is guided to the first transport path 21 by the main gate 18, and the transport rear end is held by the discharge roller 31 in the non-corrugated state. In this state, it is once discharged onto the first discharge tray 41. Next, the main gate 18 is switched and the first discharge roller 3
When the sheet 1 is reversed, the sheet S is switched back and reversed, and the sheet S passes through the reverse conveyance path 23 and the transport roller 2
It is sent to the double-sided copying unit 2 by 5. continue,
The sheet S is guided to the circulation conveyance path 35 by the sub-gate 38, conveyed through the circulation conveyance path 35, and then sent to the return conveyance path 24 of the apparatus main body 1. Then, a different image is formed on the second surface by performing the transfer and fixing process again. Up to this point, the first discharge roller 3
1 is switched to the corrugated state. After that, when the first discharge tray 41 is selected, the sheet S passes through the first transport path 21 by the main gate 18 and the first discharge roller 31 causes the second surface to face the first side. It is stored in the discharge tray 41. Further, when the second discharge tray 42 is selected, the sheet S is guided to the second transport path 22 by the main gate 18 and transported by the transport roller 25 through the discharge transport path 37,
Of the second discharge roller 32 with the second surface facing upward.
It is accommodated in the discharge tray 42.

According to the copying machine of the first embodiment described above, the following effects can be obtained especially when performing double-sided copying. In the case of double-sided copying, in order to reverse the sheet S, first, the sheet S is passed through the first discharge roller 31 until the trailing end of the sheet is held, and then the first discharge roller 31 is reversed to convey the sheet S in reverse. When the sheet S is fed into the path 23, that is, when the sheet S is switched back, the first discharge roller 31 is in the corrugation non-applied state. Therefore, corrugation is not applied to the sheet S fed into the double-sided copying process, and the sheet S is conveyed to the transfer and fixing process without causing a conveyance failure due to the corrugation. After that, when the sheet S is accommodated in the first discharge tray 41, the first discharge roller 31 has been switched to the corrugation-applied state, and thus the sheet S is discharged with the curl suppressed by the corrugation. .

As described above, when the first discharge roller 31 has the normal function of discharging the paper S, the first discharge tray 4 is provided.
When the corrugation is applied in order to improve the accommodation ability in 1 and the corrugation is not necessary for feeding the paper S to the next conveyance process (in this case, the conveyance process for double-sided copying), the solenoid is used. The state 60 is switched to the non-corrugated state. That is, good transportability of the sheet is realized both when the sheet S is discharged outside the apparatus and when it is transported to the next double-sided copying process inside the apparatus.

C. Application Example of First Embodiment The double-sided copying unit 2 of the copying machine is detachably attached to the apparatus main body 1. When the double-sided copying unit 2 is not attached, as shown in FIG. 25 serves as a discharge roller for discharging the paper S to the second discharge tray 42. Therefore, the transport roller 25 needs to be a corrugation roller when the duplex copying unit 2 is not attached to the apparatus body 1. Therefore, for example, in consideration of the case where the user first uses only the apparatus main body 1 and retrofits the duplex copying unit 2, the transport roller 25
Is preferably set in advance to a roller that can be switched between two states of corrugation application and non-application similar to the first discharge roller 31.

Next, second to fifth embodiments of the present invention in which the form of the first discharge roller is different will be described with reference to the drawings. In each drawing, the same components as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

(2) Second Embodiment (FIGS. 6 to 9) A. Configuration of Second Embodiment As shown in FIGS. 6, 8 and 9, a plurality of first discharge rollers (hereinafter, simply referred to as discharge rollers) 70 according to the second embodiment are provided on a roller shaft 73. In the case of four), first and second rollers 7 to which cylindrical roller bodies 74 are fixed
It is composed of 1, 72. The roller bodies 74 of the rollers 71 and 72 are elastically in contact with each other. Then, the corrugation imparting members 75 are arranged between the roller bodies 74 that are adjacent to each other in the axial direction. Each of these corrugation imparting members 75 is a relatively thin rod having a rectangular cross section, which is curved in an arc shape. When the arc direction is along the circumferential direction of the lower first roller 71, the tip portion thereof is It can come into contact with the roller shaft 73 of the first roller 71. 8 and 9, reference numerals 76 and 77 denote chutes that guide the paper S to the discharge roller 70.

As shown in FIG. 7, the corrugation imparting members 75 are integrally connected at their base ends by a connecting rod 80 extending in the axial direction of the discharge roller 70.
It is designed to rotate integrally with 0 as an axis. Both ends of the connecting rod 80 are machine frames 8 fixed to the apparatus body 1.
It is rotatably supported by 1, 82. When the discharge roller 70 is viewed from the axial direction, the corrugation imparting member 75 has its tip end portion wrapped around the contact portion (nip) of the roller body 74 of the rollers 71 and 72, and the upper end surface thereof is above the nip. In this case, the corrugation is applied (FIG. 8).
reference). Further, when the tip end is in contact with the roller shaft 73 of the lower first roller 71 and the upper end surface is lower than the outer peripheral surface of the roller body 74 of the first roller 71, the corrugation is not applied. . Switching between the corrugation-applied state and the non-applied state is performed by a solenoid (switching means) 83 fixed to one machine casing 81, as shown in FIG.

As shown in FIGS. 7 to 9, this solenoid 83 is similar to that of the first embodiment, but the solenoid main body 8
4 and the plunger 85, the plunger 85
Is oriented horizontally toward the side of the paper S on which the paper is discharged by the discharge roller 70. The connecting rod 80 is attached to the tip of the plunger 85.
An arm 86 fixed to one end of and extends downward is pin-connected. A return spring 87, which is supported by the machine frame 81 in parallel with the forward / backward direction of the plunger 85, is hooked on the lower end of the arm 86.

In this case, the plunger 85 retracts to the solenoid main body 84 side when the solenoid 83 is energized, and advances by the force of the return spring 87 when deenergized. Then, in the case of normal non-energization, as shown in FIG. 7, the arm 86 rotates the corrugation imparting member 75 via the connecting rod 80 by the force of the return spring 87 in the direction of the arrow a, that is, downward so as not to impart corrugation. It will be in a standing position. Next, solenoid 8
When 3 is energized, the plunger 85 retreats against the force of the return spring 87, and the arm 86 rotates the corrugation imparting member 75 via the connecting rod 80 in the arrow b direction, that is, upward, to bring the corrugation imparting state. To do.

B. Operation of Second Embodiment Also in the case of the second embodiment, as in the case of the first embodiment, when the sheet S is switched back by the discharge roller 70 in the case of double-sided copying, corrugation is imparted by the solenoid 83. When the member 75 is held in the non-applied state and the paper S is ejected from the ejection roller 70 to the first ejection tray 41, the corrugation imparting member 75 is switched to the corrugation imparting state. When the corrugation imparting member 75 is in the corrugation imparting state, the sheet S is subjected to upward pressure from the corrugation imparting member 75 and at the same time, downward pressure from the upper and lower roller bodies 74. Therefore, pressure is applied to the sheet S by the corrugation providing member 75 and the roller body 74 alternately in the vertical direction, and corrugation is provided.

Also according to the second embodiment, the corrugation is not applied to the paper S fed into the double-sided copying process, and the paper S is conveyed to the transfer and fixing process without causing the conveyance failure due to the corrugation. . After that, when the sheet S is accommodated in the first ejection tray 41, the ejection roller 70 is switched to the corrugation-applied state, so that the sheet S is ejected with the curl suppressed by the corrugation.

(3) Third Embodiment (FIGS. 10 and 1)
1) A. Configuration of Third Embodiment In the third embodiment, the main gate 1 is replaced with the corrugation imparting member 75 of the second embodiment.
8 is a corrugation imparting member. The main gate 18 is arranged between the roller bodies 74 of the rollers 71 and 72 adjacent to each other in the axial direction (in this case, there are four roller bodies 74 in the axial direction, so the main gate 18 has three
First, the discharging roller 70 is supported by a moving mechanism (switching means) (not shown) so as to be able to come into contact with and separate from the discharging roller 70. Then, when it moves to the discharge roller 70 side, as shown in FIG. 10, its tip end enters between the upper and lower roller shafts 73 and comes close to the roller shaft 73 of the first roller 71. Main gate 1
8 is in the corrugation-provided state in which the tip end portion is inserted between the upper and lower roller shafts 73 by moving to the discharge roller 70 side, and the separated state is the corrugation state as shown in FIG. 11A. It is the non-grant position.

B. Operation of the Third Embodiment When the sheet S is switched back by the discharge roller in the case of double-sided copying, first, as shown in FIG. 11A, the main gate 18 is held in the non-applied state, and the sheet S is not fed. It is operated so that S is guided to the discharge roller 70 side. When the paper S is conveyed onto the first discharge tray 41 and the rear end of the conveyance is held by the discharge rollers 70, the main gate 18 is moved downward as shown in FIG.
Is reversed and the sheet S is sent to the reverse conveyance path 23.

On the other hand, when the paper S is discharged from the discharge roller 70 to the first discharge tray 41, as shown in FIG.
The main gate 18 is switched to the corrugated state. When the sheet S enters the discharge roller 70 in the corrugation-applied state, the sheet S receives a downward pressure from the main gate 18, and at the same time, the upper and lower roller bodies 74.
Receives upward pressure from. Therefore, the corrugation is applied to the sheet S by the pressure applied alternately by the main gate 18 and the roller body 74 in the vertical direction.

Also in the third embodiment, the corrugation is not applied to the paper S fed into the double-sided copying process, and the paper S is conveyed to the transfer and fixing process without causing the conveyance failure due to the corrugation. . After that, when it is stored in the first discharge tray 41,
Since the discharge roller 70 has been switched to the corrugation-applied state, the sheet S is ejected with the curl suppressed by the corrugation. Further, in the case of the third embodiment, since the main gate 18 is shared as having the original two functions of the guide member for the paper S and the corrugation imparting member, the number of parts is reduced and the structure accompanying it is reduced. Is simplified and the cost is reduced.

(4) Fourth Embodiment (FIGS. 12 and 1)
3) A. Configuration of Fourth Embodiment In the fourth embodiment, as shown in FIGS. 12 and 13, the roller shaft 73 of the upper second roller 72 is arranged.
Between each roller body 74 of the corrugation imparting member 90.
Is provided. This corrugation imparting member 90
Is a semi-circular base end portion 91 extending from a substantially rectangular tip portion 92 to form a generally horseshoe shape.
First and second locking pieces 93, 94 are formed at both ends of the. The corrugation providing member 90 has a base end portion 91.
Are eccentrically mounted on the roller shaft 73 of the second roller 72 via a torque limiter 95. The corrugation imparting member 90 rotates in the same direction as the upper first roller 71 rotates.

The discharge roller 70 rotates in the discharge direction (normal rotation)
Then, the corrugation imparting member 90 causes the second roller 7 to move.
Although it rotates in the same direction as 2, the first locking piece 93 locks on the stopper pin 96 to prevent further rotation. Second
Roller 72 continues to rotate against the torque limiter 95. When the discharge roller 70 is viewed from the axial direction in the state where the first locking piece 93 is locked to the stopper pin 96, the lower portion of the corrugation imparting member 90 overlaps the nip of the upper and lower roller bodies 74, and the lower end surface is Located below the nip. This state is the corrugation imparting state of the corrugation imparting member 90 (see FIG. 12). Further, when the discharge roller 70 rotates in the reverse direction, the corrugation imparting member 90 reverses in the same direction as the second roller 72, but this time, the second locking piece 94 locks on the stopper pin 96 and rotates further. Is blocked. Second roller 72
Continue to rotate against the torque limiter 95. When the second locking piece 94 is locked to the stopper pin 96, the corrugation imparting member 90 escapes above the nip, and this state is the corrugation imparting member 90.
Is set to the non-corrugation-added position (see FIG. 13).

B. Operation of Fourth Embodiment In the fourth embodiment, since the corrugation imparting member 90 is in the corrugation imparting state when the ejection roller 70 is rotating in the ejection direction, the paper is placed on the first ejection tray 41. When S is stored, corrugation is applied to the paper S by the corrugation applying member 90. Further, when the sheet S is switched back in the double-sided copying, the first discharge tray 41 is temporarily held by the discharge roller 70.
After discharging the paper S on the upper side, the discharge roller 70 is reversed,
The sheet S is sent to the reversal conveyance path 23. Paper S first
When the sheet is conveyed onto the discharge tray 41, the corrugation is imparted because the corrugation imparting member 90 is in the corrugation imparting state, but the corrugation imparting member 90 is in the non-corrugation imparting position at the time of reverse rotation. Promotion is suppressed.

According to the fourth embodiment, switching between the corrugation applying state and the non-applying state of the corrugation applying member 90 is automatically performed according to the rotation of the discharge roller 70 and the action of the torque limiter 95 and the stopper pin 96. Switch. Therefore, there is no need for a driving means for switching between the corrugation applied state and the non-applied state,
The cost is reduced and the reliability of operation is improved.

C. Modification of Fourth Embodiment (not shown in FIG. 14)
16) FIGS. 14 to 16 show a modified example of the fourth embodiment. In the case of this modification, instead of the corrugation providing member 90, a corrugation providing member 100 having a different shape is applied. In this corrugation imparting member 100, a flat support piece 102 extends from the cylindrical base end portion 101 fitted to the torque limiter 95 toward the main gate 18 side, and a lower surface of the tip end portion of the support piece 18 is provided.
The tongue piece 103 is formed so as to curve and extend toward the discharge roller 70.

When the discharge roller 70 rotates (normally rotates) in the discharge direction, the corrugation imparting member 100 rotates in the same direction as the upper second roller 72, and the tip of the support piece 102 moves to the upper chute 76. It abuts and further rotation is blocked, and at this time, the tongue piece 103 is located below the nip of the upper and lower roller bodies 74. This state is the corrugation imparting state of the corrugation imparting member 100 (see FIG. 15). Further, when the discharge roller 70 rotates in the reverse direction, the corrugation imparting member 100 causes the second roller 72 to move.
When the support piece 102 is rotated in the same direction as the stopper pin 9
6 to prevent further rotation. At this time,
The tongue piece 103 escapes above the nip, and this state is the corrugation non-application state of the corrugation application member 100 (see FIG. 16). The corrugation applying member 100 is provided with the tongue piece 10 in the corrugation applying state.
3 gives corrugation to the paper S.

(5) Fifth Embodiment (FIGS. 17 and 1)
8) Next, referring to FIGS. 17 and 18, a sixth embodiment of the present invention in which the discharge roller of each of the above embodiments is applied to a copying machine of a type different from the copying machine shown in FIG. explain. For convenience of explanation, the discharge roller will be described as the first discharge roller 31 of the first embodiment.

Reference numeral 110 in these figures indicates the sheet feeding unit 1.
11 is an apparatus main body in which an image forming unit 112 is set on 11. The paper feeding unit 111 is provided with a plurality of paper feeding trays 113 in a plurality of upper and lower stages. Paper tray 1
The paper S in the sheet 13 is fed to the image forming unit 120 of the image forming unit 112 via a takeaway roller 118 by a paper feed roller group 117 including a nudger roller 114, a feed roller 115, and a retard roller 116 provided on the right side of the drawing. Sent. Image forming means 120
Is a photosensitive drum 121 on which a latent image is formed by a latent image forming means (not shown), a developing device 122, and a transfer corotron 1.
23, a charge eliminating corotron 124, a fixing device 125, and the like. The sheet S is sent from the takeaway roller 118 through the pre-registration roller 130 and the registration roller 131 to a space between the photoconductor drum 121 and the transfer corotron 123, and when passing there, the photoconductor developed by the developing device 122. Body drum 12
The development on No. 1 is transferred onto the paper S. After that, the sheet S is transported to the fixing device 125 by the transport belt 132, and the transferred image is fixed.

Downstream of the fixing device 125 (on the left side in the figure),
A discharge switching unit 140 is provided. The discharge switching unit 140 includes the first discharge roller 31, a second discharge roller 142 disposed on the first discharge roller 31, and a path of the sheet S toward the discharge rollers 31 and 142. And a gate 143 for switching between. The sheet S passes through the fixing device 125 and then passes through the gate 143.
Thus, it is guided to the lower first discharge roller 31 or the upper second discharge roller 142, and is accommodated in the first discharge tray 151 or the second discharge tray 152.

Although the copying machine according to the fifth embodiment has the above basic structure, as shown in FIG.
60 can be retrofitted. The sort unit 160 is attached to the left side surface of the apparatus main body 111 by removing the first discharge tray 151, copies a plurality of originals, and discharges the paper S to the sort tray 161 for each copy. In the sorting unit 160, the transport belt 16 that transports the paper S to each sort tray 161.
2, the sheet S is transferred from the first discharge roller 31 to the conveyor belt 162, and is discharged to each sort tray 161 by the sort roller 163 provided for each sort tray 161. Since the sort roller 163 discharges the paper S to the sort tray 161, a corrugation roller is used.

In the case of this copying machine, the sorting unit 160
Is not attached, the first discharge roller 31
Since the sheet S is only discharged to the first discharge tray 151, the normal corrugation imparted state is maintained and used. When the sorting unit 160 is attached and the sorting unit 160 is used, the first discharge roller 31 is in the non-corrugated state.

According to the sixth embodiment, there is a possibility that both the function of discharging the sheet S to the outside of the apparatus and the function of causing the sorting unit 160 to convey the sheet S are selected.
The discharge roller 31 of 1 is switched between a corrugation-applied state and a non-applied state. Therefore, even if the sorting unit 160 is retrofitted, it can be easily dealt with by switching to the corrugation non-applied state without changing the first discharge roller 31 itself.

In the above first embodiment, the second
The solenoid is used as the switching means for moving the first roller in the corrugation applying state and the non-applying state by moving the first roller in the axial direction. However, the switching means in the present invention is not limited to this, and the second roller is used. Any form may be used as long as it is a means for moving. Further, each corrugation-giving member in the second to fifth embodiments is an example of the corrugation-giving member of the present invention, and is provided between the roller bodies so as to be capable of advancing and retreating to switch the corrugation-giving state and the non-giving state. Any form may be used as long as it is one.

[0057]

As described above, according to the present invention,
Whether a corrugation imparting member is provided on the roller pair that ejects the paper to the outside of the device or conveys it to the next conveying process in the device, and switches this corrugation imparting member to either the corrugation imparting state or the non-aggregating state by the switching means. Alternatively, since the pair of rollers is provided with a switching means for switching between the corrugation-applied state and the non-applied state, when the paper is ejected outside the apparatus and when it is conveyed to the next conveyance process in the apparatus. In any of the above cases, good paper transportability can be realized.

[Brief description of drawings]

FIG. 1 is a side view of a copying machine according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a discharge roller of the same embodiment.

FIG. 3 is a front view showing a corrugation-applied state of the discharge roller.

FIG. 4 is a front view showing the same corrugation non-applied state.

FIG. 5 is a front view of a copying machine that is an application example of the first embodiment.

FIG. 6 is a perspective view of a discharge roller according to a second embodiment of the present invention.

FIG. 7 is a perspective view of the corrugation imparting member of the same embodiment.

FIG. 8 is a side view showing a corrugation-applied state of the corrugation-applying member.

FIG. 9 is a side view showing the same non-corrugated state.

FIG. 10 is a side view of a corrugation imparting member according to a third embodiment of the present invention.

11A and 11B are side views showing the operation of the corrugation imparting member of the same embodiment at the time of double-sided copying, where FIG. 11A is a state in which the sheet has entered the discharge roller, and FIG. The state of being transported is shown.

FIG. 12 is a side view showing a corrugation-applied state of a corrugation-applying member according to a fourth embodiment of the present invention.

FIG. 13 is a side view showing the corrugation-non-applied state of the corrugation-applying member.

FIG. 14 is a perspective view showing a modified example of the corrugation providing member according to the fifth embodiment of the present invention.

FIG. 15 is a side view showing a corrugation-applied state of the corrugation-applying member.

FIG. 16 is a side view showing a state in which the corrugation is not applied.

FIG. 17 is a side view of a copying machine according to a sixth embodiment of the present invention.

FIG. 18 is a side view showing a state in which a sorting unit is retrofitted to the copying machine.

[Explanation of symbols]

18 ... Main gate (corrugation imparting member, guide member), 31, 70 ... Ejection roller, 51, 71 ... First roller, 52, 72 ... Second roller, 53, 73 ... Roller shaft, 54, 55, 74 ... Roller bodies, 60, 83 ... Solenoids (switching means), 75, 90, 100 ... Corrugation imparting members, S ... Paper (conveyed body), 95 ... Torque limiters, 96 ... Stopper pins.

Claims (6)

[Claims] 1. A conveyed object such as a sheet sandwiched between a pair of rollers,
A conveyance device of an image forming apparatus that conveys a roller pair in a direction corresponding to a rotation direction of the roller pair, the first roller having a plurality of roller bodies axially spaced from each other, and the roller shaft having a plurality of roller bodies. A pair of rollers each of which is provided at a distance in the axial direction and is arranged so as to be in contact with the first roller so that the other rollers contact each other; The second roller is disposed between a rotation driving unit that rotates at least one of the second rollers in a direction corresponding to the transport direction of the transported body and the roller body that is axially adjacent to the roller pair, and is sandwiched by the roller pair. A corrugation imparting member that imparts corrugation to the transported body, and a switching unit that switches the corrugation imparting member between a corrugation imparting state and a non-aggregating state on a sheet, Conveying device of the image forming apparatus characterized by comprising. 2. A guide member for guiding the transported object is provided on the roller pair, and the guide member is shared as the corrugation imparting member.
A transport device for an image forming apparatus according to claim 1. 3. The corrugation imparting member is provided on a roller shaft of the first roller or the second roller, and the switching unit is a torque limiter interposed between the roller shaft and the corrugation imparting unit. And a stopper for stopping the corrugation-giving member in the applied state and the non-applied state in accordance with the rotation of the roller shaft, and a rotation direction conversion means for converting the rotation direction of the roller shaft. The transporting device of the image forming apparatus according to claim 1. 4. The transport mode of the transported object is divided into a discharge mode in which the transported object is discharged to the outside of the apparatus, and a mid-transport mode in which the transported object is sent to the next transportation process in the apparatus. In the case of, the corrugation imparting member moves to the imparting state, and in the mid-transport mode, a control means for controlling the switching means is provided so that the corrugation imparting member moves to the non- imparting state. The conveyance device for an image forming apparatus according to claim 1, 2, or 3. 5. A conveyance device of an image forming apparatus for conveying a conveyed object such as a sheet sandwiched between a pair of rollers in a direction according to a rotation direction of the pair of rollers, wherein a plurality of roller bodies are axially arranged on a roller shaft. A first roller provided with a space therebetween, and a plurality of roller bodies provided on the roller shaft with a space in the axial direction, and arranged so as to be opposed to each other so that the respective roller bodies come into contact with the first roller. A pair of rollers including two rollers, a rotation driving unit that rotates at least one of the first roller and the second roller in a direction corresponding to the transport direction of the transported object, and the first roller By relatively moving the first roller and the second roller in the axial direction, a corrugated state in which the roller body of the first roller is arranged between the roller bodies of the second roller, and the first roller. Roller body and second roller body And a switching unit that switches to a non-corrugated state in which the roller body is in contact with each other, and a conveyance device of the image forming apparatus. 6. The transfer mode of the transferred object is divided into a discharge mode for discharging the transferred object to the outside of the apparatus and a mid-transfer mode for sending the transferred object to the next processing process in the apparatus. In the case of, the roller pair is provided with corrugation, and in the mid-transport mode, a control means is provided for controlling the switching means so that the roller pair is not provided with corrugation. 5. The conveyance device of the image forming apparatus according to item 5.