JP6357852B2 - Paper discharge device and image forming apparatus - Google Patents

Description

  In the present invention, the upper discharge roller and the lower discharge roller are rotated, and the paper on which the toner image is fixed is discharged to the discharge unit through the nip between the upper discharge roller and the lower discharge roller. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper discharge device for making paper, and an image forming apparatus including a copier, a printer, a facsimile, and a composite machine using such a paper discharge device. In particular, when the paper on which the toner image is fixed is discharged to the paper discharge unit through the nip between the upper paper discharge roller and the lower paper discharge roller, the rear end of the paper in the paper discharge direction is the lower paper discharge roller. The paper is appropriately discharged to the paper discharge unit without remaining, and the toner image fixed on the paper is not rubbed and no noise is generated. It has characteristics.

  In an image forming apparatus including a copying machine, a printer, a facsimile machine, and a complex machine of these, paper on which a toner image is fixed by a fixing device is sequentially discharged to a paper discharge unit by a paper discharge device.

  In order to sequentially discharge the paper on which the toner image is fixed in this manner to the paper output unit by the paper output device, generally, the paper on which the toner image is formed is placed on the rotating upper paper discharge roller and the lower paper discharge roller. The sheet is guided between the sheet discharge roller and the sheet discharge section through the nip between the upper sheet discharge roller and the lower sheet discharge roller.

  Here, when the paper on which the toner image is fixed in this way is discharged to the paper discharge unit through the nip between the upper paper discharge roller and the lower paper discharge roller, the paper discharged to the paper discharge unit is Since the paper is discharged while being in contact with the paper that has already been discharged onto the paper discharge unit or the paper discharge unit, resistance is added to the discharged paper.

  For this reason, when paper with high frictional resistance, paper with a long length in the paper discharge direction, paper curled when the toner image is heated and fixed, or when paper discharge speed is slow, etc. In some cases, the trailing edge of the discharged paper remains on the lower paper discharge roller and is not properly discharged to the paper discharge unit.

  If the trailing edge of the paper discharged in this way remains on the lower paper discharge roller, the next paper is discharged through the nip between the upper paper discharge roller and the lower paper discharge roller. The previous paper remaining on the lower paper discharge roller becomes an obstacle and the next paper is jammed without being discharged. The remaining paper is pushed out greatly, the paper output position of the paper is greatly shifted, or the next paper enters under the paper remaining on the lower paper discharge roller, and the paper output section There is a problem that the order of the sheets to be discharged is shifted.

  For this reason, conventionally, as shown in Patent Document 1, a convex portion is provided on the outer peripheral portion of the lower paper discharge roller, and the rear end portion of the paper remaining on the lower paper discharge roller is connected to the lower paper discharge roller. There has been proposed one in which the paper remaining on the lower paper discharge roller is ejected to the paper discharge unit by being pushed out toward the paper discharge unit by the convex portion of the side paper discharge roller.

  However, the paper on which the toner image is fixed is guided between the lower paper discharge roller and the upper paper discharge roller, which have a convex portion on the outer periphery, and between the upper paper discharge roller and the lower paper discharge roller. When the paper is discharged to the paper discharge section, the paper is rubbed strongly between the convex part of the lower paper discharge roller and the upper paper discharge roller, and the toner image fixed on the paper is rubbed with noise, etc. There was a problem that occurred.

JP 11-79514 A

  In the present invention, the upper discharge roller and the lower discharge roller are rotated, and the paper on which the toner image is fixed is discharged to the discharge unit through the nip between the upper discharge roller and the lower discharge roller. It is an object of the present invention to solve various problems as described above in a paper discharge device adapted to make paper.

  That is, according to the present invention, in the paper discharge device as described above, when the paper on which the toner image is fixed is discharged to the paper discharge unit through the nip between the upper paper discharge roller and the lower paper discharge roller, The trailing edge of the printed paper does not remain on the lower paper discharge roller, so that the paper is properly discharged to the paper discharge section, and the toner image fixed on the paper is rubbed into noise. It is an object to prevent the occurrence of the above.

In the paper discharge device according to the present invention, in order to solve the above-described problem, the upper paper discharge roller and the lower paper discharge roller are rotated so that the paper on which the toner image is fixed is transferred to the lower paper discharge roller and the lower paper discharge roller. In the paper discharge device that discharges paper to the paper discharge section through the nip with the side paper discharge roller, a kick roller having an uneven surface on the outer peripheral surface is disposed above the nip portion and is separated from the nip portion. A paper urging member provided so as to rotate at a position in the direction and urging the paper discharged through the nip between the upper discharge roller and the lower discharge roller toward the kicking roller. at a position that is not in contact with the trailing roller is provided so as to protrude on the downstream side of the nip portion toward the downstream side from the discharge direction upstream side of the nip portion Rutotomoni, paper and top discharge In a state where paper is discharged through the nip between the roller and the lower paper discharge roller, the position of the downstream end of the paper biasing member in the paper discharge direction is more than the downstream end of the lower paper discharge roller in the paper discharge direction. On the downstream side in the paper discharge direction, the kick roller is located within the front end position on the downstream side in the paper discharge direction .

Here, in the paper discharge device, when the paper on which the toner image is fixed is discharged through the nip between the upper discharge roller and the lower discharge roller, the paper discharged through the nip is The paper biasing member provided so as to protrude from the upstream side to the downstream side in the paper discharge direction from the nip portion is biased toward the kick roller that rotates above the nip portion. Thus, the outer peripheral surface of the kicking roller provided with the unevenness comes into contact.

  Even after the trailing edge of the paper passes between the nips, the trailing edge of the paper that has passed between the nips is urged toward the kicking roller by the paper urging member. The rear edge of the paper that has passed between the nips is kicked out toward the paper discharge section by the irregularities on the outer peripheral surface of the kicking roller that is in contact with the outer surface of the kicking roller provided with unevenness. Become.

  In the paper discharge device, the paper urging member is provided at a position that does not come into contact with the kicking roller, and therefore, between the paper urging member and the outer peripheral surface of the kicking roller provided with unevenness. Thus, the paper on which the toner image is fixed is not strongly pressed.

Here, when the kicking roller is provided on the upper side of the nip portion so as to rotate at an axial position away from the nip portion , the kicking roller is the same as the upper discharge roller. It is preferable to provide the rotating shaft. In this case, it is not necessary to separately provide a mechanism for rotating the kick roller, and the paper can be discharged properly by rotating the kick roller together with the upper discharge roller.

  Further, as described above, when the paper urging member is urged toward the kicking roller by the paper urging member, the paper urging member is constituted by an elastic sheet that urges the paper urging member toward the kicking roller. The biasing member can be biased toward the kicking roller by a biasing means such as a spring.

  In addition, since the paper on which the toner image has been fixed is often at a high temperature, the paper urging member for urging the paper to the roller is made of a heat-resistant material, and the paper urging member is in contact with the paper. It is preferable to reduce the friction coefficient of the portion to be generated and to suppress the generation of noise or the like by rubbing the toner image on the paper when the toner image fixed on the paper comes into contact with the paper urging member.

In the paper discharge device according to the present invention, in the state where the paper is discharged from the nip portion between the upper paper discharge roller and the lower paper discharge roller as described above, the position of the downstream end of the paper biasing member is The lower discharge roller is positioned on the downstream side in the paper discharge direction from the front end in the paper discharge direction and within the front end position on the downstream side in the paper discharge direction of the kick roller. For this reason, in the paper discharge device of the present invention, the rear end portion of the paper discharged by the kick roller remains on the lower paper discharge roller, or the top of the paper biasing member. So that the paper is properly discharged to the paper discharge unit .

  In the image forming apparatus according to the present invention, the paper discharge device as described above is used when the paper on which the toner is fixed is discharged to the paper discharge unit by the paper discharge device.

  In the paper discharge device according to the present invention, as described above, when the paper on which the toner image is fixed is discharged to the paper discharge unit through the nip between the upper paper discharge roller and the lower paper discharge roller, the paper is passed through the nip. The discharged paper is brought into contact with the outer peripheral surface of the kick roller provided with unevenness by the paper biasing member, and the rear end portion of the paper that has passed through the nip is placed on the outer peripheral surface of the rotating kick roller. Since the paper is pushed out toward the paper discharge unit due to the unevenness, the rear end portion of the paper does not remain on the lower paper discharge roller, and the paper is appropriately discharged to the paper discharge unit.

  Further, since the paper urging member is provided at a position where it does not come into contact with the kicking roller, the paper on which the toner image is fixed is placed between the paper urging member and the outer peripheral surface of the kicking roller provided with the unevenness. It is not strongly pressed down, and the occurrence of rubbing noise or the like in the portion of the toner image fixed on the paper is also suppressed.

  In the image forming apparatus using such a paper discharge device, when the paper is discharged through the nip between the upper paper discharge roller and the lower paper discharge roller, the trailing edge of the previous paper is on the lower side. The next paper is jammed without being ejected without remaining on the paper ejection roller, or the paper remaining on the lower paper ejection roller due to the next paper ejected. The paper is pushed out greatly, the paper output position of the first paper is greatly shifted, or the next paper enters under the previous paper remaining on the lower paper discharge roller and is discharged to the paper output section. The order of the sheets of paper to be moved is no longer shifted, and the occurrence of rubbing noise or the like in the toner image portion fixed on the sheets is suppressed, so that the sheet with the toner images fixed is suitable for the paper discharge section. The paper is discharged.

1 illustrates an image forming apparatus and a paper discharge apparatus according to an embodiment of the present invention, in which a toner image is formed on a paper sheet, and the paper on which the toner image is fixed is discharged by a paper discharge apparatus using an elastic sheet as a paper biasing member. FIG. In the paper discharge device according to the above-described embodiment, an upper front discharge roller, a lower paper discharge roller, a kick-out roller provided with irregularities on the outer peripheral surface, and a schematic front view of the arrangement state of the elastic sheet as viewed from the paper discharge side. is there. In the paper discharge device according to the above-described embodiment, an upper discharge roller, a lower discharge roller, a kick-out roller provided with irregularities on the outer peripheral surface, and a schematic explanatory view of the arrangement state of the elastic sheet as viewed from the side. . In the paper discharge device according to the embodiment, the paper on which the toner image is fixed is guided between the nip between the upper paper discharge roller and the lower paper discharge roller, and the elastic sheet causes the paper to be kicked out. It is the schematic front view which looked at the state contacted with the outer peripheral surface of a roller from the paper discharge side. In the paper discharge device according to the above-described embodiment, a process in which the paper on which the toner image is fixed is discharged to the paper discharge unit through the nip between the upper paper discharge roller and the lower paper discharge roller is shown in FIG. Is a schematic explanatory view of the state where the paper is guided between the nip between the upper discharge roller and the lower discharge roller as viewed from the side, and (B) is a view of the upper discharge roller and the lower discharge roller. Schematic explanatory view of the rear end portion of the paper that has passed between the nips urged by the elastic sheet to the outer peripheral surface of the kick roller, as viewed from the side, (C) is the upper discharge roller and the lower side Schematic explanation of a state in which the rear end portion of the paper that has passed through the nip with the paper discharge roller is kicked out by unevenness on the outer peripheral surface of the kick roller and the paper is discharged to the paper discharge portion from the side. FIG. In the paper discharge device according to the embodiment, the elastic sheet is a schematic front view as seen from the paper discharge side in a state where the elastic sheet is disposed on both sides of the kick roller so as to be in contact with the rotation shaft. In the modified example in which the paper urging member used in the paper discharge device according to the above embodiment is changed, the rotation lever that rotates in the vertical direction around the rotation fulcrum is directed toward the kicking roller by the urging member. FIG. 5 is a schematic explanatory view of a state in which the upper discharge roller and the kick roller are brought into contact with a rotation shaft provided with an upper side discharge roller and a kicking roller when viewed from the side surface side. In the modified example in which the paper urging member used in the paper discharge device according to the above embodiment is changed, the paper on which the toner image is fixed passes through the nip between the upper paper discharge roller and the lower paper discharge roller, and the paper discharge unit (A) is a schematic explanatory view of the state in which the sheet is guided between the nip between the upper discharge roller and the lower discharge roller, as viewed from the side, and (B). Schematic explanation of a state in which the rear end portion of the sheet that has passed through the nip between the upper discharge roller and the lower discharge roller is urged against the outer peripheral surface of the kicking roller by the rotation lever, as viewed from the side. In the figure, (C) shows that the trailing edge of the paper that has passed through the nip between the upper paper discharge roller and the lower paper discharge roller is kicked out by the irregularities on the outer peripheral surface of the kick roller, and the paper reaches the paper discharge section. It is the schematic explanatory drawing which looked at the state discharged | emitted from the side surface side.

  Next, a paper discharge device according to an embodiment of the present invention and an image forming apparatus using such a paper discharge device will be specifically described with reference to the accompanying drawings. Note that the paper discharge device and the image forming apparatus according to the present invention are not limited to those shown in the following embodiments, and can be appropriately changed and implemented without changing the gist thereof.

  In the image forming apparatus 1 of this embodiment, as shown in FIG. 1, a black imaging unit 10K that performs image formation using black toner and an image formation using cyan toner are formed therein. Four imaging units 10K including a cyan imaging unit 10C, a magenta imaging unit 10M that forms an image using magenta toner, and a yellow imaging unit 10Y that forms an image using yellow toner. , 10C, 10M, 10Y.

  In each of the imaging units 10K, 10C, 10M, and 10Y, the photosensitive member 11, the charging device 12 that charges the surface of the photosensitive member 11, and the surface of the charged photosensitive member 11 according to image information. A latent image forming device 13 that performs exposure to form an electrostatic latent image on the surface of the photoreceptor 11 and a developing device that supplies toner to the electrostatic latent image formed on the surface of the photoreceptor 11 to form a toner image. 14 and a first cleaning device 15 that removes residual toner such as toner remaining on the surface of the photoconductor 11 after the toner image formed on the surface of the photoconductor 11 is transferred to an intermediate transfer belt 21 described later. Provided.

  In this image forming apparatus 1, in each of the imaging cartridges 10K, 10C, 10M, and 10Y, the surface of the photoreceptor 11 is charged by the charging device 12, and the surface of each photoreceptor 11 thus charged is charged. The latent image forming device 13 performs exposure according to the image information, forms an electrostatic latent image according to the image information on the surface of each photoconductor 11, and forms the electrostatic image formed on the surface of each photoconductor 11. A toner of each color is supplied from the developing device 14 to the latent image, and a toner image of each color is formed on the surface of each photoconductor 11.

  Next, the intermediate transfer belt 21 is driven to rotate by driving the toner images of the respective colors formed on the surfaces of the photoreceptors 11 in the imaging units 10K, 10C, 10M, and 10Y between the driving roller 22a and the rotating roller 22b. The toner images of the respective colors formed on the surface of each photoconductor 11 are sequentially transferred to the intermediate transfer belt 21 by the primary transfer roller 23 respectively. The toner images of the respective colors are superimposed on the intermediate transfer belt 21. In addition, after the toner image formed on the surface of each photoconductor 11 as described above is primarily transferred to the intermediate transfer belt 21, the residual toner such as toner remaining on the surface of each photoconductor 11 is respectively transferred to the above-described first. 1 is removed by a cleaning device 15.

  As described above, the color toner images superimposed on the intermediate transfer belt 21 are guided to a position facing the secondary transfer roller 24.

  On the other hand, a sheet feeding cassette 2 in which sheets S are stacked and accommodated is provided at the bottom of the image forming apparatus 1, and the sheet S accommodated in the sheet feeding cassette 2 is pushed up by the push-up plate 2a and pushed up. The paper S is pulled out from the paper feed cassette 2 by the pickup roller 25, guided between the paper feed roller 26a and the separation roller 26b, and one sheet of paper S is passed between the paper supply roller 26a and the separation roller 26b. The sheet S is guided between the intermediate transfer belt 21 and the secondary transfer roller 24 at an appropriate timing by the timing roller 27, and the sheet formed on the intermediate transfer belt 21 is guided by the timing roller 27. The toner image is transferred onto the paper S by the secondary transfer roller 24. It should be noted that the residual toner such as toner remaining on the intermediate transfer belt 21 without being transferred onto the paper S is removed from the intermediate transfer belt 21 by the second cleaning device 28.

  Then, the sheet S on which the toner image is transferred as described above is guided to the fixing device 29, and after the toner image is fixed on the sheet S in the fixing device 29, the sheet S on which the toner image is fixed is The paper discharge device 30 discharges the paper to the paper discharge unit 3.

  Here, in the paper discharge device 30 in this embodiment, as shown in FIGS. 1 to 3, a plurality of upper paper discharge rollers 31 are provided on the rotation shaft 31 a with a required interval, and the upper paper discharge rollers 31 and A plurality of lower paper discharge rollers 32 are provided on the rotating shaft 32 a so as to face each other at a required interval, and the upper paper discharge roller 31 is rotated. The lower paper discharge roller 32 is rotated so that the paper S on which the toner image is fixed as described above is discharged to the paper discharge unit 3 through the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32. I have to.

  Further, in the paper discharge device 30 in this embodiment, the kicking roller 33 having a diameter larger than the outer diameter of the upper paper discharge roller 31 and having the outer circumferential surface 33a alternately provided with irregularities in the circumferential direction, A plurality of rotation shafts 31 a of the upper paper discharge roller 31 are provided so as to be positioned at a substantially central portion between the upper paper discharge rollers 31.

  Further, the upper paper discharge roller 31 is used as a paper urging member 34 that urges the paper S discharged through the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32 toward the kick roller 33. The elastic sheet 341 is discharged from the nip portion in the vicinity of the kick roller 33 provided at the center of the rotation shaft 31a at a position where it does not contact the kick roller 33 or the upper paper discharge roller 31. It is provided so as to incline upward from the upstream side in the direction toward the downstream side.

  Further, in this elastic sheet 341, the sheet S is guided between the nip between the upper discharge roller 31 and the lower discharge roller 32 along an inclined portion 341 a inclined upward from the upstream side toward the downstream side in the discharge direction. In a state where it is not removed, the upper discharge roller 31 and the kicking roller 33 are brought into contact with the rotary shaft 31a provided.

  When the sheet S on which the toner image is fixed is sent toward the nip between the upper discharge roller 31 and the lower discharge roller 32, as shown in FIGS. The inclined portion 341a of the elastic sheet 341 that is in contact with the rotation shaft 31a provided with the paper discharge roller 31 and the kicking roller 33 is pushed down by the paper S, and the leading edge of the paper S is discharged on the upper side. While being guided between the nip between the roller 31 and the lower discharge roller 32, the sheet S is kicked out by the elastic sheet 341 by the elastic restoring force of the elastic sheet 341 provided with the irregularities by the inclined portion 341a of the elastic sheet 341. The outer peripheral surface 33a of 33 is urged to come into contact. In this state, the sheet S is sent to the sheet discharge unit 3 through the nip between the upper sheet discharge roller 31 and the lower sheet discharge roller 32 that rotate.

  Further, the sheet S on which the toner image is fixed in this way is sent toward the sheet discharge unit 3 through the nip between the upper sheet discharge roller 31 and the lower sheet discharge roller 32, and is shown in FIG. As described above, even after the rear end portion of the sheet S passes between the nips, the rear end portion of the sheet S is provided with a kick roller 33 provided with irregularities by the inclined portion 341a of the elastic sheet 341. The kick roller 33 rotates while being in contact with the outer peripheral surface 33a of the paper S, and as shown in FIG. 5C, the rear end of the sheet S is formed by the unevenness provided on the outer peripheral surface 33a of the kick roller 33. Is kicked out toward the paper discharge unit 3, and the rear end portion of the paper S passes through the inclined portion 341 a and the lower paper discharge roller 32 in the elastic sheet 341 and is appropriately discharged to the paper discharge unit 3. It becomes like this.

  Here, in the paper discharge device 30 in this embodiment, the elastic sheet 341 is disposed in the vicinity of the kicking roller 33 attached to the central portion of the rotation shaft 31a of the upper paper discharge roller 31 as described above. Therefore, even the paper S having a small width is appropriately brought into contact with the outer peripheral surface 33a of the kick roller 33 provided with irregularities by the elastic sheet 341, and is provided on the outer peripheral surface 33a of the kick roller 33. Due to the unevenness, the rear end portion of the paper S is appropriately kicked out toward the paper discharge unit 3, and the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32 even if the paper S has a small width. The paper is properly discharged from the middle to the paper discharge unit 3.

  Further, in the paper discharge device 30 in this embodiment, the trailing edge of the paper S that has passed through the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32 as described above is kicked with unevenness. While making it contact appropriately with the outer peripheral surface 33a of the taking-out roller 33, the rear end portion of the sheet S is formed by the unevenness provided on the outer peripheral surface 33a of the kicking roller 33 so that the inclined portion 341a in the elastic sheet 341 In order for the sheet to be properly discharged to the paper discharge unit 3, the downstream end in the paper discharge direction of the inclined portion 341 a of the elastic sheet 341 is the nip portion between the upper paper discharge roller 31 and the lower paper discharge roller 32. Further, it is set so as to be within the downstream end position of the kick roller 33 in the sheet discharge direction on the downstream side in the sheet discharge direction.

  Further, since the sheet S on which the toner image is fixed by the fixing device 29 as described above is often at a high temperature, the elastic sheet 341 is made of PPS (polyphenylene sulfide) having excellent heat resistance and creep resistance. It is preferable to use what is comprised with resin. Further, in order to prevent the toner image fixed on the paper S from coming into contact with the elastic sheet 341 and generating noise such as rubbing on the toner image, the surface of the inclined portion 341 a of the elastic sheet 341 in contact with the paper S is suppressed. It is preferable to perform a coating treatment with a release agent such as PTFE (polytetrafluoroethylene) coating. As the elastic sheet 341, for example, a sheet having a thickness of 0.07 to 0.25 mm and a length of the inclined portion 341a of 18 to 24 mm is used. For example, the pressing force for pressing the inclined portion 341a of the elastic sheet 341 against the paper S can be set to 0.02 to 0.5N, although it varies depending on the amount and the like.

  In this embodiment, only one elastic sheet 341 is provided at a position in the vicinity of the kicking roller 33 provided in the central portion of the rotation shaft 31a of the upper discharge roller 31. The position and number of the sheets 341 are not particularly limited, and the sheet S is appropriately brought into contact with the outer peripheral surface 33a of the kick roller 33 provided with irregularities by the elastic sheet 341, and the sheet S is outer peripheral surface of the kick roller 33. It is sufficient that the sheet is appropriately discharged to the sheet discharge unit 3 by the unevenness provided on 33a.

  For example, as shown in FIG. 6, the elastic sheet 341 is kicked out at the central portion of the rotation shaft 31 a of the upper paper discharge roller 31 at a position where it does not come into contact with the kick roller 33 or the upper paper discharge roller 31. The paper S is disposed on both sides of the roller 33 so that the paper S is evenly pressed against the outer peripheral surface 33a of the kick roller 33 provided with unevenness on both sides of the kick roller 33 so that the paper S The paper can be appropriately discharged to the paper discharge unit 3 by the unevenness provided on the outer peripheral surface 33a.

  In this embodiment, the paper urging member 34 that urges the paper S discharged through the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32 toward the kick roller 33. Although the elastic sheet 341 is used, the paper urging member 34 is not limited to this.

  For example, as shown in FIG. 7, the paper urging member 34 extends from the upstream side toward the downstream side in the paper discharge direction from the nip portion between the upper paper discharge roller 31 and the lower paper discharge roller 32. The rotation lever 342 that rotates in the vertical direction around the rotation fulcrum 342a at the position upstream of the sheet discharge roller 32 in the sheet discharge direction is positioned so as not to contact the kick roller 33 and the upper sheet discharge roller 31. And an urging member 343 such as a tension coil spring that urges the rotation lever 342 to rotate upward. The urging member 343 causes the rotation lever 342 to move to the kick-out roller 33. When the paper S is not guided between the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32, the rotating lever 342 is moved to the upper paper discharge roller 3. And trailing rollers 33 and can be adapted to contact the rotary shaft 31a provided.

  Here, even when such a paper urging member 34 is used, the paper S on which the toner image is fixed is sent toward the nip between the upper paper discharge roller 31 and the lower paper discharge roller 32. 8A, the rotation lever 342 that is in contact with the rotation shaft 31a provided with the upper discharge roller 31 and the kicking roller 33 is pushed down by the sheet S. The leading edge of the sheet S is guided between the nip between the upper sheet discharge roller 31 and the lower sheet discharge roller 32, and the sheet S is moved by the rotating lever 342 urged upward by the urging member 343. The outer peripheral surface 33a of the kicking roller 33 provided with unevenness is urged and brought into contact. In this state, the sheet S is sent to the sheet discharge unit 3 through the nip between the upper sheet discharge roller 31 and the lower sheet discharge roller 32 that rotate.

  Then, the sheet S is sent out to the sheet discharge unit 3 through the nip between the upper sheet discharge roller 31 and the lower sheet discharge roller 32 in this way, and as shown in FIG. Even after the section has passed between the nips, the trailing edge of the sheet S is still in contact with the outer peripheral surface 33a of the kicking roller 33 provided with irregularities by the rotating lever 342. As shown in FIG. 8C, the take-out roller 33 rotates and the rear end portion of the paper S is kicked out toward the paper discharge unit 3 by the unevenness provided on the outer peripheral surface 33a of the kick-out roller 33. As a result, the rear end portion of the paper S exceeds the rotation lever 342 and the lower paper discharge roller 32, and the paper is appropriately discharged to the paper discharge unit 3.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Paper feed cassette, 2a Push-up board 3 Paper discharge part 10K, 10C, 10M, 10Y Imaging unit 11 Photoconductor 12 Charging device 13 Latent image forming device 14 Developing device 15 First cleaning device 21 Intermediate transfer belt 22a Drive Roller, 22b Rotating roller 23 Primary transfer roller 24 Secondary transfer roller 25 Pickup roller 26a Paper feed roller, 26b Rolling roller 27 Timing roller 28 Second cleaning device 29 Fixing device 30 Paper discharge device 31 Upper paper discharge roller, 31a Rotating shaft 32 Lower discharge roller, 32a Rotating shaft 33 Kicking roller, 33a Outer peripheral surface 34 Paper urging member 341 Elastic sheet, 341a Inclined portion 342 Rotating lever, 342a Rotating fulcrum 343 Energizing member S Paper

Claims (6)

Rotating the upper discharge roller and the lower discharge roller to discharge the paper on which the toner image has been fixed to the discharge section through the nip between the upper discharge roller and the lower discharge roller. In the apparatus, a kicking roller having an uneven surface is provided on the upper side of the nip portion so as to rotate at an axial position away from the nip portion, and the upper discharge roller and the lower side. A paper urging member that urges the paper discharged through the nip of the paper discharge roller toward the kick roller is positioned upstream of the nip portion in the paper discharge direction at a position where it does not contact the kick roller. Rutotomoni provided so as to protrude on the downstream side of the nip portion toward the downstream side from the side, to the sheet discharge the sheet through the nip portion between the upper discharge roller and the lower discharge roller In this state, the downstream end of the paper urging member in the paper discharge direction is positioned downstream of the downstream discharge tip of the lower paper discharge roller in the paper discharge direction, and the paper is discharged from the kick roller. A paper discharge device characterized in that it is within the tip position on the downstream side in the direction .   2. The paper discharge apparatus according to claim 1, wherein the kick-out roller is provided on the same rotation shaft as the upper paper discharge roller.   3. The paper discharge apparatus according to claim 1, wherein the paper urging member is formed of an elastic sheet that urges the paper urging member toward the kicking roller.   3. The paper discharge apparatus according to claim 1, wherein the paper urging member is urged toward the kick-out roller by an urging unit.   5. The paper discharge device according to claim 1, wherein the paper urging member is made of a heat resistant material, and a friction coefficient of a portion in contact with the paper is lowered. Paper discharge device. An image forming apparatus that discharges a sheet on which toner has been fixed to a paper discharge unit by a paper discharge device, wherein the paper discharge device according to any one of claims 1 to 5 is used. Forming equipment.

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