JP2002145507A - Paper delivery device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper delivery device capable of improving the delivering performance and the loading property by adjusting the curl eliminating condition, and to provide an image forming device. SOLUTION: In a paper delivery device 60 provided with a delivery roller 62 provided in a paper delivery part and a pair of curl eliminating rollers 65 and 66 arranged in parallel with each other for abutment on the delivery roller along the circumferential direction of the delivery roller 62, the curl eliminating rollers 65 and 66 can be separately brought in contact or separated with/from the delivery roller, and both the curl eliminating rollers 65 and 66 eliminate the curl with abutment on the delivery roller 62 to improve the paper delivery performance. Deterioration of the loading property due to the generation of reverse curl can be prevented by forcibly releasing the abutment condition of the curl eliminating roller 65, which is positioned in the upstream in the paper sheets moving direction, on the delivery roller 62.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a paper discharge device and an image forming apparatus, and more particularly to a support structure of a roller used for paper discharge.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine, a printer, or a facsimile machine, which performs an electrophotographic copying process, an electrostatic latent image formed on a latent image carrier is subjected to a visible image processing in a developing process. Then, the visible image is electrostatically transferred to a recording sheet (hereinafter, referred to as a sheet), which is one of the recording media, and the transferred visible image is heated and fixed, for example, to obtain a copy or a record. It is supposed to be. After the sheet is fixed, the sheet is discharged toward a sheet discharge unit by a sheet discharge device. One of the structures is a structure shown in FIG. In FIG. 9, the sheet discharging device includes rollers A and B that abut against each other, and pinches and conveys the sheet S fed from the fixing device C and discharges the sheet S toward the sheet discharging tray D.

However, in this configuration, if the paper S is curled, the leading edge of the paper S passing through the rollers A and B advances in the direction in which the paper S is curled, and collides with the surface of the paper discharge tray D. As a result, the paper S may not be smoothly discharged onto the paper discharge tray D, and may be jammed, causing a so-called jam. One of the causes is a distance between the fixing device C and a contact position between the rollers A and B. This distance is one of the factors that determine the size of the image forming apparatus. As the distance increases, the height of the image forming apparatus increases.
For this reason, when the distance is shortened, the conveyance path of the sheet S fed from the fixing device C may be sharply bent.
Curling is likely to occur. In addition, the sheet S that has passed through the fixing device C may have different moisturizing states on the front and back sides. When the roller C1 on the heating source side is arranged on the same side as the sheet discharge tray D in the vertical direction, the roller C1 The surface of the sheet S that does not contact the sheet S easily expands, which also causes the sheet S to curl in the state shown in FIG.

Conventionally, in order to eliminate such curl on the paper S, for example, Japanese Patent Application Laid-Open Nos. 5-208773, 7-179258, 8-187.
For example, there is a configuration disclosed in Japanese Patent Publication No. 40 and Japanese Patent Application Laid-Open No. 6-146771. FIG. 10 is a diagram showing the principle configuration disclosed in the above-mentioned publication, and the paper discharge device has a configuration in which a pair of rollers B and B1 are brought into contact along the circumferential direction of the roller A. In this configuration, the sheet S moves along the circumferential direction of the roller A, and is folded back in the direction opposite to the direction in which the rollers B and B1 are to be curled. It is paid out without dripping. For this reason, the pair of rollers B, B1 function as curl correction rollers.

As shown in FIG. 11, the pair of rollers B and B1 are rotatably supported by a bearing bracket E whose shaft end is swingable. , B1 are arranged. The bearing bracket E is configured such that the rollers B and B1 are brought into contact with the peripheral surface of the roller A by being urged by an elastic body such as a compression spring or a leaf spring on the application point side.

[0006]

In the configuration disclosed in the above publication, it may be difficult to prevent the occurrence of a jam depending on the form of the sheet S to be curled. Each of the rollers B and B1 can be brought into contact with the roller A via the bearing bracket E in an interlocked manner. Therefore, when one roller is separated from the peripheral surface of the roller A, the other roller is also interlocked. As a result, the roller A is separated from the peripheral surface. Such a phenomenon occurs due to the thickness of the sheet S and the like. For example, when a thick sheet or the like is conveyed, a roller (FIG.
In this case, when the roller indicated by the reference numeral B) is separated from the roller A by the thick paper, the roller B1 is also separated from the peripheral surface of the roller A at the same time. For this reason, not only the conveyance failure of the paper S occurs but also the paper cannot be pressed against the peripheral surface of the roller A so that the curl can be corrected, so that the occurrence of the jam cannot be prevented. In particular, when the rollers B and B1 can be displaced in the radial direction of the roller A using an elastic body, when the thick paper is passed, the bearing bracket is naturally separated from the peripheral surface of the roller A and the roller B , B1 also move apart, making it difficult to correct the curl. Further, in the case where the curl correction is performed over the entire width direction of the paper S, the curl correction force acts on the widthwise end portion due to the bending rigidity of the paper, particularly in the case of thin paper having a weak stiffness. As a result, excessive curl correction is performed, a new curl is generated in a direction opposite to the curl, and a so-called side curl may occur. When such a new curl occurs,
The sheets discharged onto the sheet discharge tray are shifted in the width direction and fall, and the edges in the width direction are not uniform. Therefore, it is necessary to realign the edges, but such a work causes a user's inconvenience to be used, so it is necessary to improve the work.

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper discharge apparatus and an image forming apparatus having a configuration capable of reliably performing jam and curl correction in view of the problems in the conventional paper discharge apparatus and image forming apparatus described above. Specifically, it is possible to correct jams and curls regardless of the paper thickness.Moreover, the jam capacity is improved by removing jams and adjusting the degree of curl correction according to the bending rigidity of the paper, so-called waist strength. Paper ejection device and image having a configuration capable of preventing the occurrence of side curl in the opposite direction due to excessively effecting the curl correcting action, that is, preventing the occurrence of curl at both ends in the width direction of the paper and improving the discharge performance and stackability. It is intended to provide a forming apparatus.

[0008]

According to the first aspect of the present invention,
In a paper discharge device including a discharge roller provided in a paper discharge section and a pair of curl correction rollers which are arranged in parallel along the circumferential direction of the discharge roller and abut against the discharge roller, the curl correction roller is individually provided with respect to the discharge roller. It is characterized in that it can be approached and separated.

According to a second aspect of the present invention, in the paper discharge device according to the first aspect, the curl correcting rollers are each provided with a holder capable of swinging independently in a direction in which the curl correcting rollers can contact and separate from the peripheral surface of the discharge roller. It is characterized by being pivoted.

[0010] The third aspect of the present invention is the first or second aspect.
In the paper ejection device described above, the curl correction roller is supported by the curl correction roller, and the holder is urged in a direction in which the center distance between the curl correction rollers is reduced. Is brought into pressure contact.

According to a fourth aspect of the present invention, in the paper discharge device according to any one of the first to third aspects, the holders are rotatably supported by the same fulcrum.

According to a fifth aspect of the present invention, in the paper discharge device according to any one of the first to fifth aspects, the fulcrum position of the holder is set in a moving direction of the paper discharged from the curl correction roller. A contact portion between the curl correction roller located on the upstream side and the discharge roller is arranged linearly.

According to a sixth aspect of the present invention, in the paper discharge device according to the first aspect, a paper guide unit integrated with the holder is provided at a position between the curl correction rollers. It is characterized by being provided.

According to a seventh aspect of the present invention, in the paper discharge device according to the sixth aspect, the paper guide portion is arranged such that a downstream one of the holders in the moving direction of the paper to be discharged is located below the upstream one. It is characterized in that the tip positions are positioned so as to overlap.

According to an eighth aspect of the present invention, in the paper discharging device according to any one of the first to seventh aspects, the curl correcting roller is arranged so that the curl correcting roller has a width direction perpendicular to a moving direction of the discharged paper. Are provided at two places along the outer periphery of the curl correction roller in the width direction of the paper, and pinch rollers which are provided separately from the discharge roller and can contact an assist roller capable of transporting the paper are provided. Provided,
The pinch roller is disposed between the curl correction rollers disposed along the circumferential direction of the discharge roller when viewed from the widthwise end of the sheet.

According to a ninth aspect of the present invention, among the curl correcting rollers, the curl correcting roller positioned upstream in the moving direction of the sheet can forcibly release the contact state with the discharge roller. It is characterized by having.

According to a tenth aspect of the present invention, when the curl correcting roller on the upstream side in the moving direction of the sheet is released from the state of contact with the discharge roller, the sheet is held until the sheet is nipped by the curl correcting roller. The paper is discharged while maintaining the posture.

[0018] The invention described in claim 11 is the invention according to claims 1 to 1
0 is used for an image forming apparatus.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram illustrating an example of an image forming apparatus using a paper ejection device according to an embodiment of the present invention. The image forming apparatus illustrated in FIG. 1 has a combined function of a copier and a printer. The image forming apparatus according to the present invention is not limited to this, but includes not only a facsimile apparatus or a multifunction apparatus but also a single function apparatus.

In FIG. 1, the image forming apparatus has an image reading section 3 for reading an image of a document arranged at an upper portion, and the image forming section 1 is provided below the image reading section 3 via a space S (see FIG. 1). It is located approximately in the center of the device. Below the image forming unit 1, a paper feeding unit 2 is arranged.

In the image forming apparatus, as shown in FIG. 1, a manual paper feed table 47 for performing manual paper feed is provided on the right side of the image forming apparatus so as to be freely opened and closed. Manual paper feed table 4
Reference numeral 7 is normally stored in the image forming apparatus, and is used by being rotated about the fulcrum 47J as required and in a state where the reference numeral 7 is tilted. From the tip side of the manual paper feed table 47, an auxiliary table 47a stored in the manual paper feed table 47
Can be pulled out.

In the image forming section 1, a charging device 6 for charging the surface of the photoreceptor 5 is provided around a drum-shaped photoreceptor 5 as an image carrier, and image information is applied to the surface of the photoreceptor 5 by laser light. An exposure device 7 for irradiating; a developing device 8 for visualizing an electrostatic latent image formed by exposing the surface of the photoconductor 5; a transfer device 9 for transferring a toner image developed on the photoconductor 5 to a sheet 42; A cleaning device 10 that removes and collects toner remaining on the surface of the photoconductor 5 later is disposed. The paper feed unit 2 includes a paper feed cassette 21 for mainly storing and storing unused paper 42. Paper cassette 2
A backing paper or the like may be set in 1. Paper cassette 2
Reference numeral 1 is detachable from the image forming apparatus from the front side of the apparatus, thereby improving operability and workability at the time of sheet supply. Paper 42 is loaded on the bottom plate 22 rotatably supported in the paper feed cassette 21, and is pressurized by the spring 24 so as to press the uppermost paper 42 against the paper feed roller 23. In the paper feed unit 2, when an image forming command is issued, the uppermost sheet 42
Is fed out of the paper feed cassette 21 by the rotation of the paper feed roller 23, and is conveyed to the registration roller 14 provided in front of the transfer unit (the position of the transfer device 9). Transported paper 4
2 is temporarily stopped by the registration rollers 14 and fed at a timing such that the positional relationship between the toner image on the photoreceptor 5 and the leading end of the sheet 42 becomes a predetermined position, and the sheet 2 is transferred. The toner image is copied when passing through the copy section.

The image reading section 3 scans an image of an original (not shown) placed on the contact glass 32 and scans the original.
The reading traveling body 31 of 4M reciprocates. Image information scanned by the reading traveling body 31 is read as an image signal by a photoelectric conversion element 44 such as a CCD installed behind the lens 31a. The read image signal is digitized and processed. The image reading unit 3 forms an electrostatic latent image on the surface of the photoconductor 5 by emitting light from a laser diode (not shown) of the exposure device 7 based on the image-processed signal. That is, the optical signal from the laser diode reaches the photoconductor 5 via a known polygon mirror or lens, and forms an electrostatic latent image on the surface of the photoconductor 5. The electrostatic latent image moves with the rotation of the photoconductor 5 and is visualized by toner supplied from the developing device 8,
It further moves to the transfer device 9. Although not shown,
An automatic document feeder that automatically feeds a document onto a contact glass is mounted above the image reading unit 3. The automatic document feeder can be arbitrarily attached and detached, and need not always be provided in the image forming apparatus.

In the space S, a paper discharge tray 60 for accommodating the paper 42 discharged from the fixing device 11 after the fixing is provided. The paper discharge tray 60 is fixed to the paper discharge tray 60 via the paper discharge device 61. The sheet 42 that has passed through the apparatus 11 is discharged.
The paper 42 on which copying has been completed has the toner image fixed thereon while passing through the fixing device 11, and reaches the discharge roller 62 in a state where the paper image is inverted once before passing through the fixing device 11 from the paper feeding unit 2.

The details of the sheet discharging device 61 disposed behind the fixing device 11 are shown in FIGS.
In FIG. 2, the paper discharge device 61 includes a plurality of paper discharge paths 61A, 61B, and 61C that are continuous with a paper path formed by a heating roller 11A and a pressure roller 11B provided in the fixing device 11. I have. At the entrance of each paper discharge path, there are provided claw-shaped transport path switching means 63 and 64 which can swing to positions shown by a solid line and a two-dot chain line. In FIG. 2, reference numerals G1 and G2 indicate paper discharge rollers provided at the direction change positions of the respective paper discharge paths.

In each of the paper discharge paths, a paper discharge path 61A which reaches the paper discharge tray 60 is provided with a discharge roller 62 constituting a main part of the paper discharge device 61, and is arranged along the circumferential direction facing the discharge roller 62. A pair of curl correction rollers 65 and 66 are provided. The curl correction rollers 65 and 66 have a configuration that can independently contact and separate from the discharge roller 62. FIG. 3 is a view showing one of the contact / separation mechanisms. The curl correcting rollers 65 and 66 are pivotally mounted on rotatable holders 68 and 69 with the support shaft 67 supported by the support bracket 67A as a common fulcrum. Supported. The support bracket 67A is fastened and fixed to a support member 100 supported in the image forming apparatus.

Among the holders 68 and 69, the holder 68 that supports the curl correction roller 65 positioned upstream in the moving direction (the direction indicated by the arrow in FIG. 3) corresponding to the conveying direction of the sheet 42 is supported. A curl correction roller 65 is supported at one swing end with the shaft 67 as a boundary, and one end of an elastic body 70 such as a tension spring shown in FIG.
In FIG. 3, a counterclockwise rotational bias is applied about the support shaft 67 to cause the curl correction roller 65 to rotate the discharge roller 62.
Is pressed against. In the holder 69 that supports the curl correction roller 66 positioned downstream in the moving direction of the paper 42, the curl correction roller 66 is provided at one swing end with the support shaft 67 as a boundary.
And one end of an elastic body 71 such as a compression spring shown in FIG. 4 is disposed at the other swinging end, and a curl correction roller 66 is provided by applying a clockwise rotational bias in FIG.
Is pressed against the discharge roller 62.

The holders 68 and 69 are urged by the elastic members 70 and 71 in a direction in which the distance between the axes of the curl correcting rollers 65 and 66 is reduced. Rollers 65 and 66 are pressed against each other, and the paper 4
2 constitutes a nip portion capable of nipping and conveying.

A guide member for guiding the movement of the paper 42 is provided between the holders 68 and 69. In the configuration shown in FIG. 3, the curl correction roller 65 located on the downstream side in the movement direction of the paper 42 is The holder 69 is supported by a guide piece 69A that is located near the peripheral surface of the discharge roller 62 and extends toward the holder 68 on the upstream side in the movement direction.

Since the present embodiment has the above configuration,
When the sheet 42 is introduced as indicated by an arrow in FIG. 3, the sheet moves along the peripheral surface of the discharge roller 62 by the curl correcting rollers 65 and 66, and is folded in a direction opposite to the direction in which the curl is generated. This corrects the curl. When the leading edge of the paper 42 enters the nip portion formed by the curl correction roller 65 and the discharge roller 62 located on the upstream side in the moving direction of the paper 42, the curl correction roller 65 is moved according to the thickness of the paper 42. Is displaced in a direction that changes the abutting state.

When the paper 42 is thick, the amount of the curl correction roller 65 separating from the discharge roller 62 increases, but the curl correction roller 65 located on the downstream side in the movement direction of the paper 42 moves.
6 is in pressure contact with the discharge roller 62 independently of the curl correction roller 65 on the upstream side. Therefore, even when the curl correction roller 65 on the upstream side is separated from the discharge roller 62, the pressure contact state with the discharge roller 62 is maintained. As a result, even when the pressing force against the discharge roller 62 on the curl correcting roller 65 on the upstream side in the moving direction is reduced, the sheet 42 is secured by the curl correcting roller 66 located on the downstream side in the moving direction, and the nipping and conveying force is secured. As a result, the curl can be moved in the direction in which the curl is corrected, that is, along the peripheral surface of the discharge roller 62, and the curl is returned in the direction opposite to the direction in which the curl is generated.

The sheet 42 passing through the curl correcting roller 65 located on the upstream side in the moving direction is conveyed while being held by the curl correcting roller 66 located on the downstream side in the moving direction. The tip is guided by 69A. As a result, even when the curl correction by the curl correction roller 65 on the upstream side is not sufficient, the leading end of the sheet 42 does not abut on the peripheral surface of the curl correction roller 66 on the downstream side in the movement direction, and the occurrence of jam is prevented. You can move with.

Next, another embodiment according to the embodiment of the present invention will be described. In FIG. 3, a support shaft 67, which forms the same fulcrum with respect to the holders 68 and 69, has a straight line passing through a nip portion where the curl correction roller 65 and the discharge roller 62 located on the upstream side in the moving direction of the sheet 42 contact. In FIG.
(Dashed line).

Since the present embodiment has the above configuration,
Even when the leading end of the sheet 42 abuts on the guide piece 69A of the holder 69, the holder 69 located on the downstream side in the moving direction of the sheet 42 is not rotated. The contact state is not changed. In particular, there is no counterclockwise displacement that affects the contact state. As a result, the curl correction roller 66 and the curl correction roller 65
Irrespective of the case where the sheet 42 is separated from the sheet 2, and even if the leading end of the sheet 42 collides with the guide piece 69 </ b> A, the state of contact with the discharge roller 62 can be maintained in a state where curl correction is possible.

As a configuration of the guide member provided between the curl correction rollers 65 and 66, as shown in FIG.
It is also possible to form it on a holder 68 that supports the curl correction roller 65 located on the upstream side in the moving direction of the sheet 42 (the portion indicated by reference numeral 68A in FIG. 5). In this case, it is possible to completely prevent a situation in which the leading end of the paper 42 is caught along the moving direction of the paper 42, and thus it is possible to reliably prevent the occurrence of a jam between the curl correction rollers 65 and 66.

Next, another example according to the embodiment of the present invention will be described. The embodiment shown in FIG. 6 is characterized in that the guide portion provided on the holder located on the upstream side in the moving direction of the paper overlaps the upper portion of the guide portion of the holder located on the downstream side in the moving direction. In FIG. 6A, guide portions 68A and 69A are formed in the holders 68 and 69 near the peripheral surface of the discharge roller 62, respectively.
Of these guide portions, a guide portion 68A of the holder 68 located on the upstream side in the movement direction is provided with a guide mylar 72 which is integrated with the guide portion 68A and is continuous as shown in FIG. 6B. The guide mylar 72 is positioned at a position where the tip of the guide mylar 72 overlaps the upper portion of the holder 69. In FIG. 6, the elastic bodies 70 and 71 shown in the previous drawings are omitted, but they are provided in the same manner as in the previous drawings.

Since the present embodiment has the above configuration,
Even if the holder 68 swings for some reason,
If the swing amount is smaller than the overlap amount, the holder 6
Since the moving path of the paper 42 is continuous between 8 and 69 without interruption, the situation in which the paper 42 collides in the middle of the moving path is eliminated, and the occurrence of a jam can be prevented.

Next, still another example according to the embodiment of the present invention will be described. 4 and 7, the discharge roller 62 and the curl correction rollers 65 and 66 are arranged in two places in the width direction of the sheet 42 corresponding to the direction perpendicular to the moving direction of the sheet 42, and the width of the sheet 42 Outside the discharge roller 62 and the curl correction rollers 65 and 66 in the direction, an assist roller 73 that can pinch and convey the paper 42 and a pinch roller 74 that can contact and interlock with the discharge roller 62 are provided separately from the discharge roller 62. I have. The pinch roller 74 is disposed between the curl correction rollers 65 and 66 that are disposed along the circumferential direction of the discharge roller 62 in FIG. The pinch roller 74 can be pressed against the assist roller 74 by being pivotally supported by a leaf spring indicated by reference numeral 75 in FIG. 7, and can be linked with the rotation of the assist roller 74.

The pinch roller 74 is a curl correction roller 6
5 and 66, the nip portion with respect to the sheet 42 is only at the contact position with the assist roller 74. Therefore, unlike the case of the nip portion formed by the curl correction rollers 65 and 66 and the discharge roller 62, the paper 42 to be nipped and conveyed has a substantially horizontal discharge direction as shown by a reference numeral F1 in FIG. Direction. On the other hand, the sheet 42 passing through the nip portion constituted by the discharge roller 62 and the curl correcting rollers 65 and 66 is connected to the curl correcting roller 66 on the downstream side in the movement direction by the discharge roller F2 in FIG. It has an angle of about 30 degrees with respect to the tangential direction at the contact position with the roller 62, that is, the horizontal direction.
For this reason, no excessive curl correcting force acts on both ends in the width direction of the paper 42, and the paper 4 remains substantially horizontal.
2 can move. As a result, the sheet 42 is discharged in a so-called straight state without curling at the width direction end, so that the sheet 42 is discharged onto the discharge tray 60 and stacked. In this case, there is no curl and the loadability is not impaired. That is, if the sheets are stacked with the curl, the edges of the stacked sheets 42 are likely to be uneven, and new work such as aligning the edges again after discharging is required. Thus, such careless work can be eliminated. In the present embodiment, as shown in FIG. 4, the curl correcting action is set to a range of 95 mm from the center of the sheet 42 in the width direction, and the discharge roller 62 and the curl correcting roller 6 correspond to this position.
5, 66 are arranged. The horizontal transport position is set to a range of 175 mm corresponding to the B5 size, and the assist roller 73 and the pinch roller 74 are arranged in this range.

Since the present embodiment has the above configuration,
The sheet 42 is pinched and conveyed in the width direction, and the curl correcting force on the width direction end side is prevented from acting, so that the end portion is not curled by the curl correcting force. As a result, the curl in the direction opposite to the curl does not occur at the width direction end, and the paper can be discharged in a so-called horizontal state, so that the edges of the discharged papers 42 are not uniform. Nothing. In particular, in the case of narrow paper such as a postcard, the operations of the discharge roller 62 and the curl correcting rollers 65 and 66 sufficiently affect the operation. Further, in the case of wide paper in which thin paper or recycled paper is often used. It is possible to improve the stackability when the paper is discharged without curling at the width direction end.

Still another example according to the embodiment of the present invention will be described. The feature of the present embodiment is that, in the curl correction mode in the above embodiment, the paper fed from the fixing device is not corrected so strongly, and the paper is discharged in a flat state. FIG. 8 is a perspective view showing a main part of the present embodiment, and FIG.
The same components as those shown in FIG.

In FIG. 8, the support member 100 is provided with a mechanism for canceling the pressing force of the curl correction roller 65 located on the upstream side in the sheet moving direction with respect to the discharge roller 62. The pressure relieving mechanism includes a solenoid 80 mounted on the support member 100 and a release lever 81 that can swing by connecting one of its swing ends to an actuator of the solenoid 80.

The release lever 81 is a member that swings in a state in which it can move in a seesaw manner in the horizontal direction by a support shaft 82 attached to the support member 100, and one of the swing ends is connected to the actuator of the solenoid 80 as described above. The other end of the elastic body 70, one end of which is connected to a holder 68 that supports the curl correction roller 65, is hooked to the other of the swing ends.

On one side of the swinging end of the release lever 81, one end of a release elastic body 83 having a stronger elastic force than the elastic body 70 is hooked on the side opposite to the side pulled by the actuator of the solenoid 80. ing. The solenoid 80 has a habit of being pulled when it is excited to pull the actuator into the main body. For this reason, the release lever 81 is normally operated, that is, when the solenoid 80 is in the non-excited state, the elastic body 7 due to the habit of the release elastic body 83.
It swings in the direction of pulling 0. As a result, the holder 68 on which the elastic body 70 is hung by the traction operation of the elastic body 70 through the swing of the release lever 81 swings in a direction in which the curl correction roller 65 is pressed against the peripheral surface of the discharge roller 62. be able to.

When the release lever 81 swings when the solenoid 80 is in the non-excited state, the bent piece 81A formed on the release lever 81 comes into contact with the inner surface of the cutout 100A formed on the support member 100. Regulations.

The solenoid 80 is excited when a drive signal is output from a control unit (not shown) by a signal from an operation panel (not shown). The case where the solenoid 80 is excited is a case where the curl correction form by the correction curls 65 and 66 is canceled. Specifically,
This is a case where the paper is discharged in a state where the direction of the curl generated when the paper is fed from the fixing device 11 is kept as it is. In such a state, the curl is corrected by the curl correcting rollers 65 and 66, in other words, since the curling is not performed in the direction opposite to the direction of the curl when the curl is fed from the fixing device 11, when the reverse curl occurs. This can prevent the paper stacking property from being deteriorated.

Since the present embodiment has the above-described configuration, it is desirable to add a curl in a direction opposite to the direction of the curl generated when the curl is fed out of the fixing device 11 by the curl correcting rollers 65 and 66. In the case of the paper discharge mode with no paper quality, when the mode is selected on the operation panel, the solenoid 80 is excited. The excitation of the solenoid 80 causes the release lever 81 to swing in a direction to be pulled toward the solenoid 80 against the urging of the release elastic member 82. For this reason, the elastic body 70 hooked to the other of the swing ends of the release lever 81 contracts by its own elastic force, so that the urging force against the curl correction roller 65 located on the upstream side in the sheet moving direction, that is, Discharge roller 62
The contact pressure against the pressure is eliminated. As a result, only the curl correction roller 66 located downstream of the paper moving direction is in contact with the discharge roller 62, so that a nipping and transporting structure by the discharge roller 62 and the curl correction roller 66 is obtained. . According to such a nipping / conveying mode, since the posture of the sheet when the sheet is fed from the fixing device 11 is kept as it is, when the sheet is ejected to the sheet ejection tray, the curl in the reverse direction is prevented from increasing. It is possible to suppress the displacement of the edges in the width direction of the stacked sheets.

[0048]

According to the first and second aspects of the present invention,
A pair of curl correction rollers abutting along the circumferential direction of the discharge roller can be individually supported by the holder and independently contacted and separated from the discharge roller. Thus, even when one of the curl correction rollers is separated from the discharge roller, the other curl correction roller can be kept in contact with the discharge roller. As a result, the paper ejected regardless of the paper thickness can be pressed against the ejection rollers to form a curl in a direction opposite to the direction in which the curl is generated. Can be reliably prevented.

According to the third aspect of the present invention, since the curl correcting roller can be pressed against the discharge roller by urging the curl correcting roller so that the center distance between the curl correcting rollers is reduced, the curl correcting efficiency can be improved. Even if only one curl correction roller is in contact with the discharge roller, paper is pressed against the peripheral surface of the discharge roller, and the paper is shaped to follow the peripheral surface of the discharge roller to correct the curl. In addition, it is possible to prevent the loadability from being deteriorated.

According to the fourth aspect of the present invention, since the holders supporting the curl correcting roller are configured as the same fulcrum, not only the structure in which a plurality of holders are provided is simplified, but also the structure is simplified. Space in the vicinity of the holder can be reduced.

According to the fifth aspect of the present invention, the fulcrum position of the holder is located at the contact position between the curl correcting roller and the discharge roller located on the upstream side in the sheet moving direction, that is, on the straight line passing through the nip portion. Since the position of the holder does not shift even if the paper collides with the curl correction roller on the upstream side, the contact position between the curl correction roller and the discharge roller can be held and the curl correction can be performed. State can be maintained, and the occurrence of jam can be prevented.

According to the sixth and seventh aspects of the present invention, since the guide member is provided between the curl correcting rollers,
It is possible to prevent the leading edge of the paper from abutting the peripheral surface of the curl correction roller, thereby preventing the occurrence of a jam. In particular, in the invention according to claim 7, since the leading end of the guide member on the downstream side in the moving direction of the sheet is positioned below the guide member on the upstream side, the sheet is moved from the guide member on the upstream side to the downstream side in the moving process. Since the leading end is not impacted by the guide member when it is delivered to the guide member, it is satisfactorily delivered to the curl correcting roller on the downstream side and the curl correcting operation can be reliably performed.

According to the eighth aspect of the present invention, the pinch roller disposed in a state of being located between the curl correcting rollers in the circumferential direction of the discharge roller separately from the curl correcting roller is different from the curl correcting roller in the width direction of the sheet. Since it is provided outside the position, a portion where no curl correction is performed is provided outside the curl correction roller in the width direction of the paper. For this reason, excessive curl correcting force is not applied to the side of the sheet by transporting the weak or thin paper by the pinch roller and the assist roller, so that the side may curl in the curl correcting direction. Thus, it is possible to prevent the stackability of the discharged sheets from deteriorating.

According to the ninth and tenth aspects of the present invention,
The contact state of the curl straightening roller located on the upstream side of the paper moving direction with the discharge roller can be forcibly released, so that the paper is curled by the curl straightening roller and the discharge roller located on the downstream side of the paper moving direction. It will be nipped and conveyed. Therefore, reverse curl is less likely to occur than when the paper is pinched and conveyed by the curl correction roller on the upstream side in the moving direction of the paper while following the peripheral surface of the discharge roller. Deterioration of the loading performance when loading can be prevented. In particular, in the case of paper of weak paper quality,
The edges in the width direction are likely to be uneven when stacked on the paper output tray due to the curl of reverse curl.However, since such curling is not performed, the paper can be stacked without deteriorating the stackability on the paper output tray. Can be discharged.

According to the eleventh aspect of the present invention, the curl can be reliably corrected, and the jam at the time of the curl correction can be reliably prevented while moving between the curl correcting rollers. In addition to improving the stackability by eliminating paper curl, it is possible to eliminate paper curls and jams by eliminating the situation where the curl correction operation causes new curls. It is also possible to prevent an increase in work such as alignment work after discharge.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of an image forming apparatus to which a paper discharge device for describing an embodiment of the present invention is applied.

FIG. 2 is a diagram showing a configuration of a paper discharge device for describing an embodiment of the present invention.

FIG. 3 is a view showing an arrangement of a discharge roller and a curl correction roller used in the paper discharge device shown in FIG. 2;

FIG. 4 is a perspective view illustrating a main part of the sheet discharging device illustrated in FIG. 2;

FIG. 5 is a view showing another embodiment relating to the arrangement of the discharge roller and the curl correction roller shown in FIG. 3;

6A is a diagram showing another embodiment relating to the arrangement of the discharge roller and the curl correction roller shown in FIG. 3, and FIG.
Is a side view, and (B) is an enlarged view of a position indicated by reference numeral (B) in (A).

FIG. 7 is a schematic side view for explaining still another example of the embodiment of the present invention.

FIG. 8 is a perspective view for explaining still another example according to the embodiment of the present invention.

FIG. 9 is a schematic diagram showing a conventional example of a paper discharge device.

FIG. 10 is a diagram illustrating an example of a configuration for solving a problem in the paper discharge device illustrated in FIG. 9;

FIG. 11 is a diagram showing a specific example of the configuration shown in FIG. 9;

[Explanation of symbols]

42 paper 60 paper discharge device 62 discharge roller 65 curl correction roller 66 located on the upstream side in the paper movement direction 66 curl correction roller located on the downstream side in the paper movement direction 67 support shafts 68 and 69 having the same fulcrum guides 68a and 69a guide Section 72 Guide mylar 73 which is one of the guide sections 73 Assist roller 74 Pinch roller 80 Solenoid which is one of the members forming a mechanism for releasing the abutment of the curl correction roller located on the upstream side in the paper movement direction 81 Paper movement Release lever 83 which is another member constituting a mechanism for releasing the abutment of the curl correction roller positioned on the upstream side in the direction 83

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadashi Kusumi 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd. (72) Takaya Murashiki 1-3-6 Nakamagome, Ota-ku, Tokyo・ F term in Ricoh Co., Ltd. (reference) 2H072 AB07 BA03 BA12 CA01 CA02 CB09 JA02 3F049 AA01 CA33 DA11 DA12 LA02 LA05 LA07 LB03 3F053 HA03 HB01 LA02 LA05 LA07 LB03 3F101 FA01 FB11 FC05 LA02 LA05 LA07 LB03

Claims (11)

[Claims] 1. A paper discharge device comprising a discharge roller provided in a paper discharge portion and a pair of curl correction rollers which are arranged in parallel along the circumferential direction of the discharge roller and abut against the discharge roller. A sheet discharging device which can be individually brought into contact with and separated from rollers. 2. The paper discharging device according to claim 1, wherein the curl correcting rollers are each supported by a holder that can swing independently in a direction in which the curl correcting rollers can contact and separate from a peripheral surface of the discharging roller. A paper ejection device characterized by the above-mentioned. 3. The paper discharging device according to claim 1, wherein the holder supported for each of the curl correcting rollers is urged in a direction in which a distance between the curl correcting rollers decreases. A paper discharge device wherein the curl correction roller is pressed against the discharge roller. 4. The paper discharging device according to claim 1, wherein said holders are rotatably supported by the same fulcrum. 5. The paper ejection device according to claim 1, wherein the fulcrum position of the holder is a curl located at an upstream side in a moving direction of the paper discharged from the curl correction roller. A sheet discharge device, wherein a contact portion between a straightening roller and the discharge roller is linearly arranged. 6. The paper discharging device according to claim 1, wherein a paper guide unit integrated with the holder is provided at a position between the curl correction rollers. Discharge device characterized by the following. 7. The paper ejection device according to claim 6, wherein the paper guide portion is configured such that a downstream side of the holder in the moving direction of the discharged paper overlaps a lower portion of an upstream side. A paper ejection device characterized in that a leading end position is positioned. 8. The paper ejection device according to claim 1, wherein the curl correcting roller is provided at two positions along a width direction that is a direction perpendicular to a moving direction of the discharged paper. A pinch roller which is disposed separately from the curl correction roller in the width direction of the sheet and is provided separately from the discharge roller and which can contact an assist roller capable of transporting the sheet is provided. Is disposed between the curl correcting rollers disposed along the circumferential direction of the discharge roller when viewed from the widthwise end of the sheet. 9. The sheet discharging device according to claim 1, wherein, among the curl correcting rollers, a curl correcting roller positioned upstream in a moving direction of the sheet is forcibly set to the curl correcting roller. A sheet discharging device having a configuration capable of releasing a contact state with a discharging roller. 10. The paper discharge device according to claim 9, wherein when the curl correction roller on the upstream side in the moving direction of the paper is released from the contact with the discharge roller, the paper is applied to the curl correction rollers. A sheet discharge device that discharges a sheet while maintaining a posture until the sheet is nipped. 11. An image forming apparatus using the sheet discharging device according to claim 1. Description: