JP2004002035A - Carrying device of image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize good carrying property in either case when paper is ejected outside the device and when paper is carried to the next carrying process in the device. <P>SOLUTION: An eject roller 31 having both functions of ejecting paper into an eject tray and of reversing paper in the dual face copy mode for feeding to the next carrying process is constituted of first and second rollers 51 and 52. In the respective rollers, roller bodies 54 and 55 are respectively fixed on the roller shaft 53 with a constant pitch, the second roller 52 being axially movable, the corrugation providing state for alternatively arranging the roller bodies 54 and 55 and the corrugation non-providing state for making contact with each other being able to be switched by a solenoid 60. When paper is ejected, the corrugation providing state is selected for providing corrugation to the paper, and when paper is sent to a dual face copy unit in the dual face copy mode, the corrugation non-providing state is selected. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
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, and more particularly, to a conveying apparatus including a pair of rollers for conveying an image-formed sheet in the apparatus or discharging the sheet outside the apparatus. About.
[0002]
[Prior art]
2. Description of the Related Art Generally, an image forming apparatus such as a copying machine using an electrophotographic process supplies sheets one by one from a paper feed tray in which a large number of sheets are stacked and stored, and inputs the sheets one by one to the image forming unit. After forming an image on a sheet based on the obtained image signal, the sheet is discharged out of the apparatus. In recent years, a copying machine provided with a duplex 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 has been formed on the first surface by the image forming means is conveyed through the circulation conveyance path, the sheet is reversed in the middle of the circulation conveyance path, and then sent to the image formation means again. An image is formed on the second surface.
[0003]
In such a double-sided copying function, a method of switching back the paper is used when the paper is reversed. The switchback path is generally provided in the apparatus, but for the purpose of downsizing the apparatus, the rear end of the sheet is placed on a discharge tray for discharging the sheet outside the apparatus in the case of normal single-sided copying. 2. Description of the Related Art There is provided a copying machine of a type in which a sheet is temporarily discharged while being held, and then the sheet is circulated starting from the rear end of the conveyance. That is, the size of the apparatus is reduced by sharing the switchback path with the discharge path.
[0004]
The paper transport method in the apparatus is such that the paper is guided between a pair of rollers in which two rollers are opposed to each other, and is transported in a direction corresponding to the rotation direction of the roller pair while sandwiching the paper by a frictional force generated between the two rollers. The method is common. In this case, a so-called corrugation roller is used as the discharge roller for discharging the paper to the outside of the apparatus, in particular, in order to prevent deterioration of the accommodation capacity in the discharge tray due to curl (curl) remaining on the discharged paper. There are many. The corrugation roller is a roller that forms a weak wavy line (hereinafter referred to as corrugation) that extends in the transport direction on the sheet as the sheet passes and thereby corrects curl and strengthens the so-called waist of the sheet. . For example, Japanese Unexamined Patent Publication (Kokai) No. 60-171963 discloses a corrugation roller in which corrugation is applied to a sheet passing therethrough by changing the width of a plurality of roller bodies that come into contact with each other. There is also a corrugation roller in which the roller bodies of the respective rollers are displaced in the axial direction so as to be in non-contact, and the pressure of the adjacent roller bodies is applied alternately up and down along the axial direction to apply corrugation.
[0005]
[Problems to be solved by the invention]
By the way, in the above-described copying machine having a double-sided copying function in which the paper discharge path is shared with the switchback path, when the paper is reversed, first, the discharge roller holds the rear end of the paper transport by the discharge roller. The sheet is once discharged onto a discharge tray until the sheet is discharged, and then the discharge rollers are rotated in reverse, and the sheet is fed to the conveyance path for duplex copying with the rear end of the conveyance first.
[0006]
Here, when the discharge roller is the corrugation roller, the corrugation described above is effective for discharging the paper.However, when the paper is sent to the conveyance path for double-sided copying for reversal, the corrugation occurs. Transport failure occurs. In other words, a plurality of normal roller pairs for transporting the paper to the image forming unit again are arranged in the transport path, and when the corrugated paper enters these roller pairs, the leading edge of the paper may break. In this case, the corrugation is strengthened as the paper passes and the paper is damaged, such as wrinkles, or a paper jam occurs. If the sheet is damaged, the sheet cannot be used even if an image is formed on the second surface. That is, the corrugation roller is effective when the paper is finally discharged out of the apparatus and there is no subsequent transport process, but when the pass point is to continuously transport the paper in the apparatus, the action is reversed. This was a hindrance to transportation.
[0007]
The present invention has been made in view of the above circumstances, and is an image capable of achieving good paper transportability in both cases where paper is discharged out of the apparatus and transported to the next transport process in the apparatus. It is an object of the present invention to provide a conveying device for a forming apparatus.
[0008]
[Means for Solving the Problems]
The present invention has been made to achieve the above-described object, and includes a discharge mode in which a transported object sandwiched between a pair of rollers is discharged to the outside of the apparatus and a transporting intermediate mode in which the transported object is sent to a next transport process in the apparatus. A first roller in which a plurality of roller bodies are provided on a roller shaft at an interval in an axial direction, and a plurality of roller bodies are arranged on the roller shaft in an axial direction. A roller pair including a second roller and a second roller disposed so as to be in contact with the first roller so that the respective roller bodies are in contact with each other, and at least one of the first roller and the second roller, Rotational driving means for rotating in a direction corresponding to the transport direction of the transported object, and disposed between the roller bodies axially adjacent to each other in the roller pair, and corrugated the transported object sandwiched between the roller pairs. A corrugation imparting member, a corrugation imparting member, switching means for switching between a corrugation imparting state and a non-imparting state with respect to the transported body, and in the case of the discharge mode, the corrugation imparting member is in the imparting state, and during the conveyance, And a control means for controlling the switching means so that the corrugation applying member is in the non-application state in the mode.
[0009]
In the present invention, a guide member that guides the transported object to the roller pair can be used as a corrugation applying member. Further, a corrugation applying member is provided on the roller shaft of the first roller or the second roller, and the switching means is provided with a torque limiter interposed between the roller shaft and the corrugation applying means, and a rotation of the roller shaft. May be configured by a combination of a stopper that stops the corrugation applying member between the applied state and the non-applied state, and a rotation direction converting unit that changes the rotation direction of the roller shaft.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(1) First Embodiment (FIGS. 1 to 5)
A. Configuration of First Embodiment
A-1. Copier configuration
FIG. 1 shows a copying machine according to a first embodiment of the present invention. Reference numeral 1 in the figure denotes an apparatus main body. On one side (left side in FIG. 1) of the apparatus main body 1, a duplex copying unit 2 is detachably mounted. On the apparatus main body 1, a document table (not shown) on which a document is placed and set is placed. Is provided. The platen is provided with a reading device that optically reads an image of a document.
[0011]
An image forming unit 3 is provided in the apparatus main body 1. The image forming unit 3 receives a photosensitive drum 4, a memory 5 in which image signals of a document read by the reading device are input and stored, and an image signal output from the memory 5, Image writing means 6 for forming an image signal on the photosensitive drum 4 as an electrostatic latent image; and a developing device 7 for visualizing or developing the electrostatic latent image on the photosensitive drum 4 with a developer such as toner. And a fixing drum 10 including a transfer drum for transferring an image developed on the photosensitive drum 4 to a sheet (conveyed body) S, and a fixing roller pair 9 for fixing the image transferred to the sheet S to the sheet S. It has.
[0012]
Below the image forming means 3 in the apparatus main body 1, a sheet feed tray 11 in which a number of sheets S are stacked and stored is detachably inserted. The paper feed tray 11 is designed to be attached to and detached from the inside of the apparatus main body 1 from the near side (the near side in the drawing). From the paper feed tray 11, paper S is supplied to the image forming means 3 one by one as follows by a paper feed roller group 15 composed of a nudge roller 12, a feed roller 13 and a retard roller 14. ing.
[0013]
The uppermost sheet S in the sheet feeding tray 11 is first pulled out by the nudger roller 12 and then sent 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. It is guided to the registration roller 17. When two or more sheets S are pulled out by the nudger roller 12 and are multi-fed, the retard roller 14 rotates in the direction opposite to the conveying direction, so that the lower sheets S other than the uppermost sheet S are both rollers. It can be prevented from entering between 13 and 14. The paper S that has reached the registration roller 17 is adjusted in the transport timing and the transport attitude here, and then is sent between the photosensitive drum 4 and the transfer drum 8 of the image forming unit 3. After passing between the drums 4 and 8, the sheet S is sent 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 the bottom to the top, and the paper S passing through the fixing device 10 is moved right and left by the main gate (guide member) 18 by the main gate (guide member) 18. Is switched to one of the first and second transport paths 21 and 22, respectively. The first and second transport paths 21 and 22 are connected by a reverse transport path 23 provided above the main gate 18. The apparatus main body 1 is provided with a return transport path 24 that opens to the left side surface and joins the supply transport path 16.
[0014]
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 the first discharge tray 41 formed on the upper surface of the apparatus main body 1 Housed on top. The sheet S is 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 to the second transport path 22 on the left side by the main gate 18 is sent to the duplex copying unit 2 by the transport roller 25.
[0015]
In the case of double-sided copying, the sheet S is guided to the first conveyance path 21 by the main gate 18 and is once discharged onto the first discharge tray 41 while the rear end of the conveyance is held by the first discharge rollers 31. Then, when the main gate 18 is switched and the first discharge roller 31 rotates in reverse, the first discharge roller 31 switches back and reverses, and is sent to the duplex copying unit 2 by the transport roller 25 through the reverse transport path 23.
[0016]
The double-sided copying unit 2 has a relatively thin outer shell having the same depth as the apparatus main body 1, and a hinge plate 33 integrally formed at the lower end is hinged to the apparatus main body 1 via a horizontal pin 34. And open and close left and right about the pin 34 as an axis. Normally, the duplex copying unit 2 is configured such that a hook (not shown) attached to the upper end is engaged with the apparatus main body 1 so that the set state facing the apparatus main body 1 is maintained.
[0017]
A circulating transport path 35 for receiving the sheet S from the transport roller 25 and transporting the sheet S to the return transport path 24 of the apparatus main body 1 is provided vertically in the duplex copying unit 2. A plurality of transport rollers 36 for transporting the sheet S are provided in the circulation transport path 35. Further, from the upper part of the circulation conveyance path 35, a discharge conveyance path 37 which opens to the left side is branched, and at the branch point, the path of the sheet S is routed to one of the circulation conveyance path 35 and the discharge conveyance path 37. Is provided. The paper S guided to the discharge conveyance path 37 by the sub-gate 38 is discharged to the outside by the second discharge roller 32 and is stored on the second discharge tray 42. When the sheet S is guided to the circulation conveyance path 35, the paper S is conveyed through the circulation conveyance path 35 by the transport rollers 36 and returns to the apparatus main body 1 by entering the return conveyance path 24.
[0018]
A-2. Configuration of first discharge roller
Next, the configuration of the first discharge roller 31 according to the present invention will be described. The first discharge roller 31 is, as shown in FIG. 2, a so-called roller pair in which a lower first roller 51 and an upper second roller 52 are arranged to face each other. The first roller 51 includes a plurality of (four in this case) roller bodies 54 coaxially fixed at equal intervals in the axial direction to a roller shaft 53. On the other hand, the second roller 52 has the same configuration, and a plurality of roller bodies 55 are coaxially fixed to the roller shaft 53 at equal intervals in the axial direction. The two roller bodies 54 and 55 come into contact with each other corresponding to the location. The roller body 54 of the first roller 51 has a simple cylindrical shape, but the roller body 55 of the second roller 52 has a tapered portion 55b formed at one end of a cylindrical portion 55a. The axial length of the cylindrical portion 55a is substantially the same as that of the roller body 54 of the first roller 51, and the cylindrical portion 55a can contact the roller body 54 of the first roller 51. The pitch of the roller bodies 54 and 55 in each of the rollers 51 and 52 is equal, and the axial length of the roller body 55 of the second roller 52 is set shorter than the distance between the roller bodies 54 of the first roller 51. ing. Note that the roller body 54 is formed of a material such as rubber having appropriate elasticity capable of transporting the sheet S, and the roller bodies 55 are formed of a resin such as polyacetal and are in contact with each other.
[0019]
A driven gear 56 is fixed to one end of a roller shaft 53 of the first roller 51, and a driven gear 57 that is rotated by a rotation driving means such as a motor (not shown) meshes with the driven gear 56. Gears 58 and 59 that mesh with each other are fixed to both ends of the roller shaft 53 of each of the rollers 51 and 52. When the drive gear 57 rotates, the rollers 51 and 52 move in the forward direction (the rotation directions are opposite to each other). ).
[0020]
Although it has been described that the roller bodies 54 and 55 of the first roller 51 and the second roller 52 are in contact with each other, in the first discharge roller 31, the second roller 52 moves in the axial direction. , And the state in which the roller bodies 54 and 55 are in contact with each other, and the state in which the roller bodies 55 are disposed between the roller bodies 54 in the axial direction and are not in contact with each other. The switching is performed by a solenoid (switching means) 60.
[0021]
The solenoid 60 has a conventionally well-known structure in which a plunger 62 is inserted into a solenoid main body 61 so as to be able to advance and retreat, and is disposed close to one end (the left end in FIG. 2) of the second roller 52. The plunger 62 advances and retreats along the axial direction of the second roller 52, and an arm 63 is pin-connected to the tip of the plunger 62. The center of the arm 63 is supported via a pin 64 so as to be rotatable in the horizontal direction. On the other hand, a pulley-shaped collar 65 having a circumferential groove 65 a is fixed to one end of the second roller 52, and the tip of the arm 63 fits into the circumferential groove 65 a of the collar 65. A return spring 66 is hung on the tip side of the pin 64 of the arm 63.
[0022]
In this case, the plunger 62 retreats toward the solenoid main body 61 when the solenoid 60 is energized, and advances by the force of the return spring 66 when the solenoid is not energized. Then, in the case of normal non-energization, the arm 63 moves the second roller 52 in the direction of the arrow a along the axial direction by the force of the return spring 66 via the collar 65 as shown in FIG. At this time, each roller body 55 of the second roller 52 is located between the roller bodies 54 of the first roller 51 except for the roller body 55 on the leading end side in the moving direction. That is, the roller bodies 54 and 55 have a staggered arrangement in which the roller bodies 54 and 55 are alternately arranged vertically along the axial direction (see FIG. 3). In this case, it is preferable that the cylindrical portion 55 a of the roller body 55 be 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 the second roller 52 via the collar 65 in the direction of the arrow b along the axial direction. Let it. Then, each roller body 55 of the second roller 52 elastically contacts the roller body 54 of the first roller 51 (see FIG. 4). The interval between the roller shafts 53 of the rollers 51 and 52 is set such that the roller bodies 54 and 55 elastically contact each other. Therefore, as described above, when the roller bodies 54 and 55 are not in contact with each other, The roller bodies 54 and 55 slightly overlap in a direction perpendicular to the axial direction.
[0023]
When the solenoid 60 is not energized and the rollers 54 and 55 are in a staggered arrangement, the pressure of the rollers 54 and 55 is applied to the paper S passing through the first discharge roller 31 alternately in the width direction. This gives corrugation. The pressure applied to the sheet S from the roller bodies 54 and 55 is determined by the amount of the overlap. On the other hand, when the solenoid 60 is energized and the roller bodies 54 and 55 are in contact with each other, no corrugation is given to the sheet S passing through the first discharge roller 31. As described above, in the first discharge roller 31, the corrugation applying state in which the roller bodies 54 and 55 shown in FIG. 3 are not in contact with each other, and the rollers 54 and 55 shown in FIG. The state can be switched between two states, that is, a non-corrugated state.
[0024]
Since the second discharge roller 32 is a roller that only discharges the sheet S to the second discharge tray 41, the second discharge roller 32 has a function of switching between corrugation application and non-application as the first discharge roller 31. Instead, a corrugation roller for imparting corrugation is used.
[0025]
B. Operation of the first embodiment
The operation of the copying machine including the solenoid 60 is controlled as follows by control means (not shown). The control mode is broadly classified into a “single-sided copy mode”, a “combined copy mode”, and a “double-sided copy mode”. In each case, the control is stored in either the first discharge tray 41 or the second discharge tray 42. Is selected in advance.
[0026]
(1) Single-sided copy mode
The first discharge roller 31 is in a normal corrugation applying state.
One sheet of paper S is conveyed from the paper supply tray 11 to the registration roller 17 by the paper supply roller group 15, and after the conveyance timing and the conveyance posture are adjusted by the roller 17, the paper S is transferred to the photosensitive member 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 sheet S. Next, the sheet S passes through the roller pair 9 of the fixing device 10, where the transferred image is fixed.
[0027]
After the fixing device 10, when the first discharge tray 41 is selected, the sheet S is guided to the first conveyance path 21 by the main gate 18, and the image S is copied by the first discharge roller 31. The first discharge tray 41 is accommodated in the first discharge tray 41 with the first surface facing downward. Since the first discharge roller 31 is in a corrugated state, the sheet S is corrugated, and the sheet S is stored in the first discharge tray 41 with curling suppressed. When the second discharge tray 42 is selected, the paper 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 copy unit 2. Enter Road 35. Next, the sheet S is guided from the discharge conveyance path 37 to the second discharge roller 32 by the sub-gate 38, and is stored in the second discharge tray 42 by the second discharge roller 32 with the first surface facing upward. . Since the second discharge roller 32 is a corrugation roller, the sheet S is corrugated, and the sheet S is stored in the second discharge tray 42 while curling is suppressed.
[0028]
(2) Composite copy mode
The first discharge roller 31 is in a normal corrugation applying state.
The sheet S on which the image has been transferred to the first surface of the sheet S and has passed through the fixing device 10 is guided to the second transport path 22 by the main gate 18 and enters the circulating transport path 35 in the duplex copying unit 2. Next, after being guided to the circulation conveyance path 35 by the sub-gate 38 and conveyed through the circulation conveyance path 35, the paper is sent to the return conveyance path 24 of the apparatus main body 1. Next, a different image is formed on the first surface by performing the transfer and fixing processes again. Thereafter, when the first discharge tray 41 is selected, the sheet S is passed through the first conveyance path 21 by the main gate 18 and is discharged by the first discharge roller 31 in a state where the first surface is directed downward. 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 is transported by the transport rollers 25 to the discharge transport path 37, and the second discharge is performed. The roller 32 is stored in the second discharge tray 42 with the first surface facing upward.
[0029]
(3) Double-sided copy mode
The first discharge roller 31 is in a corrugation non-applied state when the paper is inverted, and is in a corrugation applied state when the paper is discharged.
The paper S on which the image has been transferred to the first surface and has passed through the fixing device 10 is guided to the first transport path 21 by the main gate 18, and the transport trailing end is held by the discharge roller 31 in a non-corrugated state. In this state, the sheet is temporarily discharged onto the first discharge tray 41. Next, when the main gate 18 is switched and the first discharge roller 31 rotates in the reverse direction, the sheet S is switched back and reversed, and is sent to the duplex copying unit 2 by the transport roller 25 through the reverse conveyance path 23. Subsequently, the sheet S is guided to the circulating conveyance path 35 by the sub-gate 38, is conveyed through the circulating conveyance path 35, and is sent to the return conveyance path 24 of the apparatus main body 1. Next, a different image is formed on the second surface by performing the transfer and fixing processes again. During this time, the first discharge roller 31 is switched to the corrugation application state. Thereafter, when the first discharge tray 41 is selected, the sheet S is passed through the first conveyance path 21 by the main gate 18 and is discharged by the first discharge roller 31 so that the first surface of the sheet S faces downward in the first state. 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 is transported by the transport rollers 25 to the discharge transport path 37, and the second discharge is performed. The roller 32 is stored in the second discharge tray 42 with the second surface facing upward.
[0030]
According to the copying machine of the first embodiment, the following effects are exhibited particularly when performing duplex 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 rear end of the conveyance is held, and then the first discharge roller 31 is reversely rotated to reverse the conveyance. When the paper S is fed into the path 23, that is, when the paper S is switched back, the first discharge roller 31 is in a corrugation non-applied state. Therefore, no corrugation is given to the sheet S sent to the two-sided copying process, and the sheet S is transported to the transfer and fixing process without occurrence of a transport failure due to the corrugation. Thereafter, when the paper S is stored in the first discharge tray 41, the first discharge roller 31 is switched to the corrugation application state, so that the paper S is discharged with curl suppressed by corrugation. .
[0031]
As described above, in the case of the normal function of discharging the paper S, the first discharge roller 31 enters the corrugation imparting state in order to improve the storage capacity of the first discharge tray 41. When the corrugation is not necessary to send to the next conveyance process (in this case, the conveyance process for double-sided copying), the solenoid 60 switches to the non-corrugation application state. That is, in both cases where the sheet S is discharged out of the apparatus and when the sheet S is conveyed to the next two-sided copying process in the apparatus, excellent sheet conveyance properties are realized.
[0032]
C. Application example of the first embodiment
The two-sided copying unit 2 of the copying machine is detachably attached to the apparatus main body 1. When the two-sided copying unit 2 is not attached, as shown in FIG. The sheet S functions as a discharge roller for discharging the paper S. Therefore, the transport roller 25 needs to be a corrugation roller when the duplex copying unit 2 is not attached to the apparatus main body 1. Therefore, for example, in consideration of the case where the user initially uses only the apparatus main body 1 and attaches the duplex copying unit 2 later, the transport roller 25 is provided with the same corrugation-imparting and non-imparting 2 as the first discharge roller 31 described above. It is preferable to set in advance a roller that can be switched between two states.
[0033]
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 denoted by the same reference numerals, and description thereof will be omitted.
[0034]
(2) Second embodiment (FIGS. 6 to 9)
A. Configuration of Second Embodiment
A first discharge roller (hereinafter simply referred to as a discharge roller) 70 in the second embodiment has a plurality of (in this case, four) cylindrical rollers on a roller shaft 73 as shown in FIGS. The first and second rollers 71 and 72 to which the roller body 74 is fixed. The roller bodies 74 of the rollers 71 and 72 are in elastic contact with each other. The corrugation imparting members 75 are arranged between the roller bodies 74 adjacent in the axial direction. These corrugation imparting members 75 are formed by bending relatively thin rods having a rectangular cross section in a circular arc shape, and the distal ends thereof are in a state in which the circular arc direction follows the circumferential direction of the lower first roller 71. The first roller 71 can contact the roller shaft 73. 8 and 9, reference numerals 76 and 77 denote chutes for guiding the sheet S to the discharge roller 70.
[0035]
As shown in FIG. 7, the corrugation imparting members 75 are integrally connected at a base end thereof by a connecting rod 80 extending in the axial direction of the discharge roller 70, and are rotated integrally with the connecting rod 80 as an axis. Has become. Both ends of the connecting rod 80 are rotatably supported by machine frames 81 and 82 fixed to the apparatus main body 1. When the discharge roller 70 is viewed from the axial direction, each corrugation imparting member 75 has its leading end wrapped in the contact portion (nip) of the roller body 74 of each of the rollers 71 and 72 and its upper end surface is above the nip. The case is set to the corrugation imparting state (see FIG. 8). Further, when the leading end portion 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, a corrugation non-applied state is set. . The switching between the corrugation imparting state and the non-corrugation imparting state is performed by a solenoid (switching means) 83 fixed to one machine casing 81 as shown in FIG.
[0036]
As shown in FIGS. 7 to 9, this solenoid 83 includes a solenoid body 84 and a plunger 85 similarly to the first embodiment, and the plunger 85 is horizontally positioned on the discharge side of the sheet S by the discharge roller 70. It is suitable. An arm 86 fixed to one end of the connecting rod 80 and extending downward is pin-connected to the tip of the plunger 85. On the lower end of the arm 86, a return spring 87 supported by the machine frame 81 in a direction parallel to the direction of movement of the plunger 85 is hooked.
[0037]
In this case, the plunger 85 retreats toward the solenoid main body 84 when the solenoid 83 is energized, and advances with the force of the return spring 87 when the solenoid is not energized. Then, in the case of normal non-energization, as shown in FIG. 7, the arm 86 rotates the corrugation applying member 75 in the direction of arrow a, that is, downwards, by the force of the return spring 87 via the connecting rod 80, so that no corrugation is applied. State. Next, when the solenoid 83 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 direction of arrow b, that is, upward. Corrugation is applied.
[0038]
B. Operation of the second embodiment
In the case of the second embodiment, similarly to the first embodiment, when the paper S is switched back by the discharge roller 70 in the case of double-sided copying, the corrugation applying member 75 is set to the non-applied state by the solenoid 83. When the sheet S is held and discharged from the discharge roller 70 to the first discharge tray 41, the corrugation applying member 75 is switched to the corrugation applying state. When the corrugation imparting member 75 is in the corrugation imparting state, the sheet S receives pressure upward from the corrugation imparting member 75 and simultaneously downward pressure from the upper and lower roller bodies 74. Therefore, pressure is applied to the paper S alternately by the corrugation imparting member 75 and the roller body 74 to apply corrugation.
[0039]
Also according to the second embodiment, corrugation is not applied to the sheet S sent to the double-sided copying process, and the sheet S is transported to the transfer and fixing process without occurrence of transport failure due to corrugation. Thereafter, when the paper S is stored in the first discharge tray 41, the discharge roller 70 has been switched to the corrugation application state, so that the paper S is discharged with curl suppressed by corrugation.
[0040]
(3) Third Embodiment (FIGS. 10 and 11)
A. Configuration of Third Embodiment
In the third embodiment, the main gate 18 is a corrugation imparting member instead of the corrugation imparting member 75 of the second embodiment. 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 three main gates 18 because the number of the roller bodies 74 is four in the axial direction). 70 is supported by a moving mechanism (switching means) (not shown) so as to be able to come and go. Then, when moving to the discharge roller 70 side, as shown in FIG. 10, the leading end enters between the upper and lower roller shafts 73 and approaches the roller shaft 73 of the first roller 71. The state in which the main gate 18 moves toward the discharge roller 70 and the leading end of the main gate 18 enters between the upper and lower roller shafts 73 is referred to as a corrugated state, and the main gate 18 is in a separated state as shown in FIG. , The corrugation non-application position.
[0041]
B. Operation of the third embodiment
When the paper 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 a non-applied state, and the paper S is moved to the discharge roller 70 side. Operate to lead. When the sheet S is conveyed onto the first discharge tray 41 and the rear end of the conveyance is held by the discharge roller 70, the main gate 18 is moved down as shown in FIG. Then, the paper S is fed into the reverse conveyance path 23.
[0042]
On the other hand, when the paper S is discharged from the discharge roller 70 to the first discharge tray 41, the main gate 18 is switched to the corrugation application state as shown in FIG. When the sheet S enters the discharge roller 70 in the corrugation application state, the sheet S receives a downward pressure from the main gate 18 and simultaneously receives an upward pressure from the upper and lower roller bodies 74. Therefore, corrugation is applied to the sheet S by applying pressure alternately up and down by the main gate 18 and the roller body 74.
[0043]
Also according to the third embodiment, corrugation is not applied to the sheet S sent to the double-sided copying process, and the sheet S is transported to the transfer and fixing process without occurrence of transport failure due to corrugation. Thereafter, when the paper S is stored in the first discharge tray 41, the discharge roller 70 is switched to the corrugation application state, so that the paper S is discharged with curl suppressed by corrugation. Further, in the case of the third embodiment, since the main gate 18 is shared as having the two functions of the guide member of the original paper S and the corrugation imparting member, the number of parts is reduced and the structure accompanying this is reduced. Simplification and cost reduction.
[0044]
(4) Fourth Embodiment (FIGS. 12 and 13)
A. Configuration of Fourth Embodiment
In the fourth embodiment, as shown in FIGS. 12 and 13, a corrugation imparting member 90 is provided between each roller body 74 of the roller shaft 73 of the upper second roller 72. The corrugation imparting member 90 is formed in a substantially horseshoe shape by extending a substantially rectangular distal end portion 92 from a semicircular base end portion 91, and has first and second ends at both ends of the distal end portion 92. Locking pieces 93 and 94 are formed. The corrugation imparting member 90 has a base end 91 eccentrically mounted on a 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.
[0045]
When the discharge roller 70 rotates in the discharge direction (forward rotation), the corrugation imparting member 90 rotates in the same direction as the second roller 72, but the first locking piece 93 is locked to the stopper pin 96 and The above rotation is prevented. The second roller 72 continues to rotate against the torque limiter 95. When the discharge roller 70 is viewed from the axial direction in a state where the first locking piece 93 is locked to the stopper pin 96, the lower portion of the corrugation applying member 90 is wrapped in the nip of the upper and lower roller bodies 74 and the lower end surface is It is located below that nip. This state is the corrugation applying state of the corrugation applying member 90 (see FIG. 12). When the discharge roller 70 rotates in the reverse direction, the corrugation imparting member 90 rotates in the same direction as the second roller 72, but this time, the second locking piece 94 is locked to the stopper pin 96 and further rotated. Is prevented. The second roller 72 continues to rotate against the torque limiter 95. In a state where the second locking piece 94 is locked to the stopper pin 96, the corrugation applying member 90 escapes above the nip, and this state is a corrugation non-application position of the corrugation applying member 90 (FIG. 13). reference).
[0046]
B. Operation of the fourth embodiment
In the fourth embodiment, when the discharge roller 70 is rotating in the discharge direction, the corrugation applying member 90 is in the corrugation applying state. Corrugation is applied to the sheet S by the application member 90. When the sheet S is switched back by the duplex copying, the sheet S is first discharged onto the first discharge tray 41 by the discharge roller 70, and then the discharge roller 70 is rotated in the reverse direction. Send in. When the paper S is conveyed onto the first discharge tray 41, corrugation is applied since the corrugation imparting member 90 is in the corrugation imparting state. However, when the paper S is rotated in the reverse direction, the corrugation imparting member 90 is at the corrugation imparting position. Therefore, the promotion of corrugation formation is suppressed.
[0047]
According to the fourth embodiment, the switching between the corrugation applying state and the non-application state of the corrugation applying member 90 is automatically switched according to the rotation of the discharge roller 70 and the action of the torque limiter 95 and the stopper pin 96. Therefore, there is no need for a driving means for switching between the corrugation imparting state and the corrugation imparting state, and the cost is reduced and the operation reliability is improved.
[0048]
C. Modification of the fourth embodiment (FIGS. 14 to 16)
14 to 16 show a modification of the fourth embodiment. In the case of this modification, a corrugation imparting member 100 having a different shape is applied instead of the corrugation imparting member 90. The corrugation imparting member 100 has a flat support piece 102 extending from the cylindrical base end 101 fitted to the torque limiter 95 toward the main gate 18, and a discharge roller on the lower surface of the tip of the support piece 18. The tongue 103 is formed so as to bend toward the 70 side.
[0049]
When the discharge roller 70 rotates in the discharge direction (forward rotation), the corrugation imparting member 100 rotates in the same direction as the upper second roller 72, and the tip of the support piece 102 abuts on the upper chute 76. Further rotation is prevented, 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 applying state of the corrugation applying member 100 (see FIG. 15). When the discharge roller 70 rotates in the reverse direction, the corrugation imparting member 100 rotates in the same direction as the second roller 72, and the support piece 102 is locked to the stopper pin 96, thereby preventing further rotation. At this time, the tongue piece 103 escapes above the nip, and this state is the corrugation non-applying state of the corrugation applying member 100 (see FIG. 16). In the corrugation imparting member 100, the tongue piece 103 imparts corrugation to the sheet S in the corrugation imparting state.
[0050]
(5) Fifth Embodiment (FIGS. 17 and 18)
Next, a fifth embodiment of the present invention in which the discharge rollers of the above embodiments are applied to a copying machine of a type different from the copying machine shown in FIG. 1 will be described with reference to FIGS. . For convenience of explanation, the discharge roller will be described as being the same as the first discharge roller 31 of the first embodiment.
[0051]
Reference numeral 110 in these figures denotes an apparatus main body in which an image forming unit 112 is set on a sheet feeding unit 111. The paper feed unit 111 is provided with a plurality of paper feed trays 113 in a vertical direction. The paper S in the paper feed tray 113 is formed by the image forming unit 112 via a takeaway roller 118 by a paper feed roller group 117 composed of a nudge roller 114, a feed roller 115, and a retard roller 116 provided on the right side in FIG. Sent to the means 120. The image forming unit 120 includes a photosensitive drum 121 on which a latent image is formed by a latent image forming unit (not shown), a developing device 122, a transfer corotron 123, a discharging corotron 124, a fixing device 125, and the like. The paper S is sent from the takeaway roller 118 via the pre-registration roller 130 and the registration roller 131 to the space between the photosensitive drum 121 and the transfer corotron 123, and when passing through the photosensitive drum 121, the photosensitive material developed by the developing device 122. The development on the body drum 121 is transferred onto the sheet S. Thereafter, the sheet S is transported to the fixing device 125 by the transport belt 132, and the transferred image is fixed.
[0052]
A discharge switching unit 140 is provided downstream (left side in the figure) of the fixing device 125. 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 two. After passing through the fixing device 125, the sheet S is guided by the gate 143 to the first discharge roller 31 on the lower side or the second discharge roller 142 on the upper side, and is sent to the first discharge tray 151 or the second discharge tray 152. Will be accommodated.
[0053]
The copying machine according to the fifth embodiment has the above-described basic configuration. However, as shown in FIG. 18, a sorting unit 160 can be added later. The sort unit 160 is attached to the left side of the apparatus main body 111 with the first discharge tray 151 removed. The sort unit 160 copies a plurality of originals into a plurality of copies, and discharges the sheets S to the sort tray 161 for each copy. In the sort unit 160, a transport belt 162 that transports the paper S to each sort tray 161 is provided. The paper S is transported from the first discharge roller 31 to the transport belt 162, and is provided for each sort tray 161. The sheets are discharged to the respective sort trays 161 by the sorted rollers 163. Since the sort roller 163 discharges the sheet S to the sort tray 161, a corrugation roller is used.
[0054]
In the case of this copying machine, when the sort unit 160 is not attached, the first discharge roller 31 only discharges the sheet S to the first discharge tray 151, so that the normal corrugation application state is maintained and used. . When the sort unit 160 is used when the sort unit 160 is attached, the first discharge roller 31 is set in a non-corrugated state.
[0055]
According to the fifth embodiment, the first discharge roller 31, which may select both the function of discharging the sheet S out of the apparatus and the function of transporting the sheet S to the sort unit 160, is provided by the first discharge roller 31. It is assumed that the state can be switched between a corrugation giving state and a non-giving state. Therefore, even if the sort 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.
[0056]
In the first embodiment, the solenoid is used as the switching means for switching the first discharge roller between the corrugation application state and the non-application state by moving the second roller in the axial direction. The means is not limited to this, and may be of any form as long as it moves the second roller.
Each of the corrugation imparting members in the second to fifth embodiments is an example of the corrugation imparting member of the present invention. It may be of any form as long as it is.
[0057]
【The invention's effect】
As described above, according to the present invention, a corrugation imparting member is provided on a pair of rollers for discharging a sheet to the outside of the apparatus or transporting the sheet to the next transport process in the apparatus, and the corrugation imparting member is provided with corrugation by switching means. Since the configuration is switched to one of the state and the non-application state, good paper transportability can be realized both in the case where the paper is discharged out of the apparatus and when the paper is transported to the next transport process in the apparatus. .
[Brief description of the 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 embodiment.
FIG. 3 is a front view showing a corrugation application state of the discharge roller.
FIG. 4 is a front view showing the corrugation non-application state.
FIG. 5 is a front view of a copying machine which 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 applying member of the embodiment.
FIG. 8 is a side view showing a corrugation applying state of the corrugation applying member.
FIG. 9 is a side view showing the corrugation non-application 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 illustrating the operation of the corrugation imparting member according to the embodiment at the time of double-sided copying, in which (a) a sheet enters a discharge roller, and (b) discharge is reversed and the sheet is reversed. This shows a state where the sheet is being conveyed.
FIG. 12 is a side view showing a corrugation applying 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-applying state of the corrugation applying member.
FIG. 14 is a perspective view showing a modification of the corrugation imparting member according to the fourth embodiment of the present invention.
FIG. 15 is a side view showing a corrugation applying state of the corrugation applying member.
FIG. 16 is a side view showing the corrugation non-application state.
FIG. 17 is a side view of a copying machine according to a fifth embodiment of the present invention.
FIG. 18 is a side view showing a state in which a sort unit is added to the copying machine.
[Explanation of symbols]
18: Main gate (corrugation imparting member, guide member), 31, 70: Discharge roller, 51, 71: First roller, 52, 72: Second roller, 53, 73: Roller shaft, 54, 55, 74 ... roller body, 60, 83 ... solenoid (switching means), 75, 90, 100 ... corrugation imparting member, S ... paper (conveyed body), 95 ... torque limiter, 96 ... stopper pin.

Claims (3)

A transfer device of an image forming apparatus having a discharge mode for discharging a transferred object sandwiched between a pair of rollers to the outside of the apparatus and a transfer intermediate mode for feeding the transferred object to a next transfer process in the apparatus,
A first roller in which a plurality of roller bodies are provided on the roller shaft at intervals in the axial direction; and a first roller in which a plurality of roller bodies are provided on the roller shaft at intervals in the axial direction. A roller pair consisting of a second roller which is disposed so as to be in contact with the roller body,
Rotation driving means for rotating at least one of the first roller and the second roller in a direction corresponding to a transport direction of the transported object;
A corrugation applying member that is disposed between the roller bodies adjacent in the axial direction of the roller pair and that applies corrugation to the transported object sandwiched between the roller pairs,
Switching means for switching the corrugation applying member between an applied state and a non-applied state of corrugation on the transported body,
Control means for controlling the switching means so that the corrugation applying member is in the applying state in the discharge mode, and the corrugation applying member is in the non-applying state in the halfway mode. Conveying device of the image forming apparatus. The transport device according to claim 1, wherein the corrugation imparting member is a guide member that guides the transported object to the roller pair. The corrugation imparting member is provided on a roller shaft of the first roller or the second roller, and the switching unit includes: a torque limiter interposed between the roller shaft and the corrugation imparting unit; The apparatus according to claim 1, further comprising a combination of a stopper for stopping the corrugation applying member between the applied state and the non-applied state in accordance with the rotation, and a rotation direction converting means for converting the rotation direction of the roller shaft. 2. The conveying device of the image forming apparatus according to 1.

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