Patent Application
20240409351
This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2023-093649 filed Jun. 7, 2023.
The invention relates to a sheet discharge device and an image forming apparatus.
In the related art, for example, techniques disclosed in JP2009-078873A, JP2015-212194A, JP2896245B, and JP2020-142915A have already been proposed as a technique related to a sheet discharge device.
JP2009-078873A is configured to include a discharge member that discharges paper, a paper stacking unit on which the paper discharged by the discharge member is stacked, a trailing end regulating member that regulates a trailing end position of the paper stacked on the paper stacking unit, and exhaust means for exhausting air from a corner portion that faces a reference surface of the trailing end regulating member and a paper stacking surface of the paper stacking unit.
JP2015-212194A is configured to have a discharge wall portion in which a discharge port is formed, a discharge roller for discharging a sent sheet from the discharge port, a sheet stacking unit for stacking the sheet which is discharged and falls from the discharge port, a suction unit that is opened between the discharge port in the discharge wall portion and the sheet stacking unit and that sucks air below the sheet discharged from the discharge port, and a control unit for controlling a suction operation by the suction unit. The control unit controls the suction unit such that the suction unit starts the suction operation at a timing when a trailing end of the sheet discharged from the discharge port has come out of the discharge port and stops the suction operation at a timing when a predetermined time has elapsed.
JP2896245B is configured such that in a paper discharge tray having a tray that is somewhat isolated below paper discharge means provided at an image forming apparatus body and that is attached to a side surface of the image forming apparatus body to receive and store image-formed paper discharged by the paper discharge means and side walls that are provided over the entire length of the tray on both sides between a tray upper surface and a somewhat upper side of the paper discharge means, the side walls of the paper discharge tray on both sides are surfaces that extend in a vertical direction and that have serrated roughness of which a width of a tilt surface in a horizontal direction is longer on an upstream side in a paper discharge direction than on a downstream side, and air holes are provided in the wall surfaces over almost the entire height.
In JP2020-142915A, on a paper discharge tray to which paper is transported and on which the paper is stacked, there is a full detection member that is movable according to a stacking height of the paper in order to detect the stacking height. The full detection member has a contact surface portion with which a leading end of the transported paper comes into contact and a detection unit that is positioned on a downstream side of the contact surface portion in a transport direction and that can come into contact with an uppermost layer of the paper stacked on the paper discharge tray, and a hole having an inclined edge portion inclined with respect to the transport direction of the paper is formed in the contact surface portion.
Aspects of non-limiting embodiments of the present disclosure relate to a sheet discharge device and an image forming apparatus suppressing that a posture of a sheet discharged to a discharge tray is disordered in a case of discharging the sheet, compared to a case of not including a plurality of exhaust passages that are provided in a wall surface of the discharge tray and that are inclined to extend outward of both end portions in a width direction intersecting a discharging direction of the sheet toward a lower side of the wall surface.
Aspects of certain non-limiting embodiments of the present disclosure address the above advantages and/or other advantages not described above. However, aspects of the non-limiting embodiments are not required to address the advantages described above, and aspects of the non-limiting embodiments of the present disclosure may not address advantages described above.
According to an aspect of the present disclosure, there is provided a sheet discharge device including a discharge tray that accommodates a discharged sheet with an end portion on an upstream side along a discharging direction of the sheet abutting against a wall surface, and a plurality of exhaust passages that are provided in the wall surface of the discharge tray and that are inclined to extend outward of both end portions along a width direction intersecting the discharging direction of the sheet toward a lower side of the wall surface.
Exemplary embodiment(s) of the present invention will be described in detail based on the following figures, wherein:
Hereinafter, modes for carrying out the invention (hereinafter, referred to as “exemplary embodiment”) will be described with reference to the drawings.
An image forming apparatus 1 according to exemplary embodiment 1 is configured as, for example, a color printer. The image forming apparatus 1 includes, at an upper end of an apparatus body 1a, an image reading device 2 that reads an image of a document (not shown). The image forming apparatus 1 functions as a color printer or the like that records image information sent from a host computer (not shown) or the like, in addition to functioning to copy the image of the document read by the image reading device 2.
The image forming apparatus 1 includes, inside the apparatus body 1a, a plurality of image forming devices 10 that form a toner image developed with a toner configuring a developer 4, an intermediate transfer device 20 that holds each toner image formed by each image forming device 10 and that performs transportation to a secondary transfer position where the toner image is secondarily transferred to recording paper 5, which is an example of a sheet, ultimately, a feeding device 50 that accommodates and transports the required recording paper 5 to be supplied to the secondary transfer position of the intermediate transfer device 20, a fixing device 40 that fixes the toner image secondarily transferred to the recording paper 5 by the intermediate transfer device 20, and the like. The plurality of image forming devices 10 and the intermediate transfer device 20 configure an image forming section that forms an image on the recording paper 5. The apparatus body 1a of the image forming apparatus 1 is formed by a support structural member, an exterior cover, or the like.
The image forming devices 10 include four image forming devices 10Y, 10M, 10C, and 10K that exclusively form toner images of four colors including yellow (Y), magenta (M), cyan (C), and black (K), respectively. The four image forming devices 10 (Y, M, C, K) are disposed to be in a state of being arranged in one row in an inclined state in an internal space of the apparatus body 1a. Among the four image forming devices 10 (Y, M, C, K), the yellow (Y) image forming device 10Y is relatively high as the yellow (Y) image forming device 10Y is positioned high along a vertical direction Z, and the black (K) image forming device 10K is present at a relatively low position.
As shown in
The photoconductor drum 11 forms an image holding surface that has a photoconductor layer (photosensitive layer) made of a photosensitive material on a peripheral surface of a cylindrical or columnar base material to be grounded. The photoconductor drum 11 is supported to rotate in a direction indicated by an arrow A as power is transmitted from a rotational drive device (not shown).
As shown in
The exposure device 13 irradiates the peripheral surface of the photoconductor drum 11 after charging with light configured according to information of an image input into the image forming apparatus 1 and forms an electrostatic latent image.
At a time of forming a latent image, information (signal) of an image input into the image forming apparatus 1 by any section is transmitted to the exposure device 13.
The exposure device 13 consists of an LED print head that irradiates the photoconductor drum 11 with light according to image information with a light emitting diode (LED), which is a plurality of light emitting elements arranged along an axial direction of the photoconductor drum 11, and that forms an electrostatic latent image. A device that performs deflection and scanning along the axial direction of the photoconductor drum 11 with laser light configured according to the image information may be used as the exposure device 13.
All of the developing devices 14 (Y, M, C, K) are configured such that a developing roll 141 that holds a developer to transport the developer to a developing region facing the photoconductor drum 11, an agitating and supplying member 142 consisting of a screw auger or the like that supplies the developer to pass through the developing roll 141 while agitating the developer, an agitating and transporting member 143 consisting of a screw auger or the like that transports the developer to the agitating and supplying member 142 while agitating the developer, a layer thickness regulating member 144 that regulates the amount (layer thickness) of the developer held by the developing roll 141, and the like are disposed inside a housing 140 in which an opening portion and an accommodation chamber for the developer are formed at positions facing the photoconductor drum 11. A developing voltage is supplied from a power supply device (not shown) to the developing device 14 between the developing roll 141 and the photoconductor drum 11.
For example, a two-component developer containing a non-magnetic toner and a magnetic carrier is used as developers of four colors.
The primary transfer device 15 (Y, M, C, K) is a contact-type transfer device including a primary transfer roll that rotates around the photoconductor drum 11 in contact therewith via an intermediate transfer belt 21 and that is supplied with a primary transfer voltage. As the primary transfer voltage, a direct current voltage indicating a polarity opposite to the charging polarity of a toner is supplied from the power supply device (not shown).
As shown in
As shown in
For example, an endless belt made of a material, in which a resistance adjusting agent such as carbon black is dispersed in a synthetic resin such as a polyimide resin and a polyamide resin, is used as the intermediate transfer belt 21. In addition, the belt support roll 22 is configured as a drive roll that is rotationally driven by a drive device (not shown), the belt support roll 23 is configured as a surface roll that maintains a traveling position or the like of the intermediate transfer belt 21, the belt support roll 24 is configured as a tension applying roll that applies tension to the intermediate transfer belt 21, and the belt support roll 25 is configured as a backup roll for secondary transfer.
As shown in
As shown in
The fixing device 40 is configured such that a heating rotating body 41 in a drum form or a belt form heated by a heating section so that a surface temperature is maintained at a required temperature, a pressurizing rotating body 42 in a drum form or a belt form rotating in contact with a predetermined pressure in a state substantially along an axial direction of the heating rotating body 41, and the like are disposed. An outlet roll 43 that transports the recording paper 5 on which fixing processing is performed is provided at an outlet portion of the fixing device 40. In the fixing device 40, a contact portion where the heating rotating body 41 and the pressurizing rotating body 42 are in contact with each other is a fixing processing portion in which required fixing processing (heating and pressurization) is performed.
The feeding device 50 is disposed to be present at a position on a lower side of the yellow (Y), magenta (M), cyan (C), and black (K) image forming devices 10 (Y, M, C, K). The feeding device 50 is generally configured by a plurality of (or a single) paper accommodating bodies 51 that accommodate the recording paper 5 of an appropriate size and type in a stacked state and sending devices 52 and 53 that send out the recording paper 5 one by one from the paper accommodating bodies 51. The paper accommodating body 51 is attached, for example, such that the paper accommodating body 51 can be pulled to a front surface (a side surface facing a user during operation) side of the apparatus body 1a or a front side of the page in the shown example.
Examples of the recording paper 5 include plain paper used in an electrophotographic copying machine or a printer, thin paper, an OHP sheet, and the like. In order to further improve smoothness of an image surface after fixing, for example, it is preferable that the surface of the recording paper 5 is also as smooth as possible, and for example, so-called thick paper having a relatively large basis weight, such as coated paper obtained by coating the surface of plain paper with a resin, printing art paper, or the like can also be used.
A feeding transport path 56 configured by a plurality (or a single) of pairs of paper transport rollers 54 and 55 that transport the recording paper 5 sent out from the feeding device 50 to the secondary transfer position, a transport guide (not shown), and the like is provided between the feeding device 50 and the secondary transfer device 30. The pair of paper transport rolls 55 are configured as, for example, registration rolls that adjust the transport timing of the recording paper 5. In addition, a paper discharge transport unit 58 including first to fourth paper discharge transport paths 57a to 57d for discharging the recording paper 5 sent out from the outlet roll 43 of the fixing device 40 after fixing to a sheet discharge device 60 that is an example of a sheet discharge section provided at an upper portion of the apparatus body 1a is provided at an upper portion of the fixing device 40 along the vertical direction Z.
The sheet discharge device 60 includes so-called in-body discharge type first and second discharge trays 61 and 62 provided at the upper portion of the apparatus body 1a and a third discharge tray 63 provided at a side surface (a left surface in the drawing) of the paper discharge transport unit 58 toward the outside. Inside the paper discharge transport unit 58, the first paper discharge transport path 57a that branches from the second paper discharge transport path 57b and that includes a first pair of paper discharge rolls 64 for discharging the recording paper 5 to the first discharge tray 61, the third paper discharge transport path 57c that branches from the second paper discharge transport path 57b and that includes a second pair of paper discharge rolls 66 for discharging the recording paper 5 to the second discharge tray 62, and the fourth paper discharge transport path 57d that branches from the third paper discharge transport path 57c and that includes a third pair of paper discharge rolls 67 for discharging the recording paper 5 to the third discharge tray 63 are provided.
In
In addition, inside the apparatus body 1a, as shown in
In
In addition, the reference symbol 145 (Y, M, C, K) in
In addition, the reference symbol 100 in
Hereinafter, a basic image forming operation by the image forming apparatus 1 will be described.
Herein, an operation of forming a full-color image configured by combining toner images of four colors (Y, M, C, K) using the four image forming devices 10 (Y, M, C, K) will be described.
In a case where the control device 100 receives command information requesting for an image forming operation (printing), the image forming apparatus 1 starts the four image forming devices 10 (Y, M, C, K), the intermediate transfer device 20, the secondary transfer device 30, the fixing device 40, and the like.
Then, in each image forming device 10 (Y, M, C, K), each photoconductor drum 11 first rotates in the direction indicated by the arrow A, and each charging device 12 charges the surface of each photoconductor drum 11 to each of a required polarity (a negative polarity in exemplary embodiment 1) and a required potential. Next, the exposure device 13 irradiates the surface of the photoconductor drum 11 after charging with light emitted based on a signal of an image obtained by converting information of an image input into the image forming apparatus 1 into each color component (Y, M, C, K), and each electrostatic latent image having each color component configured by a required potential difference is formed on the surface.
Next, each image forming device 10 (Y, M, C, K) performs development by each supplying a toner of a corresponding color (Y, M, C, K) charged to the required polarity (negative polarity) from the developing roll 141 and electrostatically adhering the toner to the electrostatic latent image having each color component, which is formed on the photoconductor drum 11. With the development, the electrostatic latent image having each color component formed on each photoconductor drum 11 is visualized as each toner image of each of four colors (Y, M, C, K) developed with a toner of a corresponding color.
Next, in a case where the toner image of each color formed on the photoconductor drum 11 of each image forming device 10 (Y, M, C, K) is transported to the primary transfer position, each primary transfer device 15 (Y, M, C, K) primarily transfers the toner image of each color in a state of overlapping each other in turn to the intermediate transfer belt 21 of the intermediate transfer device 20, which rotates in the direction indicated by the arrow B.
In addition, in each image forming device 10 (Y, M, C, K) that has ended primary transfer, the drum cleaning device 16 cleans the surface of the photoconductor drum 11 by scraping off and removing an adhered object. Accordingly, each image forming device 10 (Y, M, C, K) is brought into a state where the next image formation operation can be performed.
Next, the intermediate transfer device 20 holds the toner image primarily transferred in response to the rotation of the intermediate transfer belt 21 and transports the toner image to the secondary transfer position. On the other hand, the feeding device 50 sends out the required recording paper 5 to the feeding transport path 56 in accordance with the image formation operation. In the feeding transport path 56, the pair of paper transport rolls 55, which are registration rolls, send out and supply the recording paper 5 to the secondary transfer position in accordance with a transfer timing.
At the secondary transfer position, the secondary transfer roll 31 of the secondary transfer device 30 collectively and secondarily transfers the toner image on the intermediate transfer belt 21 to the recording paper 5. In addition, in the intermediate transfer device 20 that has ended the secondary transfer, the belt cleaning device 26 performs cleaning by removing an adhered object such as a toner remaining on the surface of the intermediate transfer belt 21 after the secondary transfer.
Next, the recording paper 5 to which the toner image is secondarily transferred is transported to the fixing device 40 after being peeled off the intermediate transfer belt 21 and the secondary transfer roll 31. The fixing device 40 performs necessary fixing processing (heating and pressurization) and fixes an unfixed toner image to the recording paper 5 by causing the recording paper 5 after the secondary transfer to be introduced into and to pass through the contact portion between the rotating heating rotating body 41 and the pressurizing rotating body 42. Finally, in a case of an image forming operation of forming an image on one side only, the recording paper 5 after fixing has ended is discharged to any one of the first to third discharge trays 61 to 63 provided at the upper portion of the apparatus body 1a via the first to fourth paper discharge transport paths.
In addition, in a case of forming images on both sides of the recording paper 5, the rotation direction of the first pair of paper discharge rolls 64 is switched to the reverse rotation direction while the first pair of paper discharge rolls 64 hold a trailing end of the recording paper 5, without the first pair of paper discharge rolls 64 discharging the recording paper 5 having one side on which the image is formed to the first discharge tray 61. The recording paper 5 transported in a reverse direction by the first pair of paper discharge rolls 64 is transported to the double-sided transport path 70 including the pair of paper transport rolls 69 and the like and is transported to the pair of paper transport rolls 55 again in a state where the front and back are reversed. The pair of paper transport rolls 55 send out and supply the recording paper 5 to the secondary transfer position in accordance with a transfer timing, form an image on the back surface of the recording paper 5, and discharge the recording paper 5 having the back surface on which the image is fixed to any one of the first to third discharge trays 61 to 63 provided at the upper portion of the apparatus body 1a via any one of the first to fourth paper discharge transport paths 57a to 57d.
With the operation above, the recording paper 5 having one side or both sides on which a full-color image configured by combining the toner images of four colors is formed is output.
As shown in
The sheet discharge device 60 according to exemplary embodiment 1 is configured as a so-called in-body discharge type sheet discharge device that discharges the recording paper 5 into a trunk, which is the upper portion of the apparatus body 1a of the image forming apparatus 1.
As shown in
Herein, in particular, the first discharge tray 61 including the first pair of paper discharge rolls 64 will be described as the sheet discharge device 60.
As described above, the first discharge tray 61 is configured as a so-called in-body discharge type discharge tray for discharging the recording paper 5 into the trunk of the apparatus body 1a of the image forming apparatus 1. As shown in
Both end portions of the inclined portion 611 of the first discharge tray 61 along a width direction (depth direction) Y intersecting the discharging direction of the recording paper 5 are closed by front and rear side surfaces 1b and 1c configuring the apparatus body 1a. In
As shown in
As shown in
For this reason, the recording paper 5 discharged onto the first discharge tray 61 does not immediately fall onto the first discharge tray 61 due to the presence of the air sump 75 and temporarily floats in the air. Then, in the first discharge tray 61, as air configuring the air sump 75 present below the recording paper 5 moves around the first discharge tray 61, the recording paper 5 falls onto a surface of the inclined portion 611 of the first discharge tray 61 or the like due to the weight thereof.
As a result, in the related art, in the sheet discharge device 60 configured as described above, as shown in
In order for the sheet discharge device according to exemplary embodiment 1 to suppress disorder of the posture of a sheet discharged to the discharge tray in a case of discharging the sheet, the sheet discharge device is configured to include a plurality of exhaust passages that are provided in the wall surface of the discharge tray and that are inclined to extend outward of both end portions along the width direction intersecting the discharging direction of a sheet toward a lower side of the wall surface.
In addition, the sheet discharge device according to exemplary embodiment 1 is configured such that the plurality of exhaust passages are provided in a symmetrical shape with a reference position as a center and the reference position is at, for example, the center in a direction intersecting the discharging direction of the sheet.
That is, as shown in
As shown in
As shown in
To describe further, as shown in
The plurality of ribs 81, 81 . . . are formed in an elongated protruding shape having a required width and a required height with respect to the wall surface 613 of the first discharge tray 61. Among the plurality of ribs 81, 81 . . . , between the ribs 81, 81 . . . adjacent to each other, the plurality of exhaust passages 80, 80, . . . are provided as spaces defined between the ribs 81, 81 . . . adjacent to each other.
Like the plurality of ribs 81, 81 . . . , the plurality of exhaust passages 80, 80, . . . are disposed in an inclined state to extend outward of both end portions along the width direction intersecting the discharging direction of the recording paper 5 toward the lower side of the wall surface 613 along the vertical direction Z.
The plurality of exhaust passages 80, 80, . . . are set such that each of sectional areas of the exhaust passages 80, 80 . . . increases as the heights of the plurality of ribs 81, 81 . . . increase and intervals between the plurality of ribs 81, 81 . . . increase. Conversely, the plurality of exhaust passages 80, 80, . . . are set such that each of the sectional areas of the exhaust passages 80, 80 . . . decreases as the heights of the plurality of ribs 81, 81 . . . decrease and the intervals between the plurality of ribs 81, 81 . . . decrease.
However, a total sectional area of the plurality of exhaust passages 80, 80, . . . is determined by the product of each of the sectional areas of the exhaust passages 80, 80 . . . and the total number of the exhaust passages 80, 80 . . . .
In the configuration above, it is possible for the sheet discharge device according to exemplary embodiment 1 to suppress that the posture of a sheet discharged to the discharge tray is disordered in a case of discharging the sheet, compared to a case of not including the plurality of exhaust passages that are provided in the wall surface of the discharge tray and that are inclined to extend outward of both end portions along the width direction intersecting the discharging direction of the sheet toward the lower side of the wall surface as follows.
That is, as shown in
In this case, as shown in
In this case, due to various factors such as fixing properties of the fixing device 40, absorption properties of the recording paper 5, or a state of an image formed on the recording paper 5, curves, such as a down curl that curves in a protruding shape toward a first discharge tray 61 side and an upper curl that curves in a recessed shape toward the first discharge tray 61 side, are generated in the recording paper 5 in some cases.
Immediately after the recording paper 5 is discharged onto the first discharge tray 61, the air sump 75 where air below the recording paper 5 remains is present in the sheet discharge device 60.
As shown in
For this reason, in a case where the recording paper 5 is discharged onto the first discharge tray 61, as shown in
In this case, the plurality of exhaust passages 80, 80, . . . are provided in a state of being inclined to extend outward of both end portions in the width direction intersecting the discharging direction of the recording paper 5 toward the lower side of the wall surface 613 of the first discharge tray 61. For this reason, the recording paper 5 discharged onto the first discharge tray 61 has the end portion on the upstream side along the discharging direction thereof, which comes into contact with the surfaces of the plurality of ribs 81, 81 . . . , and is guided to extend outward of both end portions in the width direction intersecting the discharging direction along inclination of the plurality of ribs 81, 81 . . . .
As a result, even in a case where a curve, such as a down curl and an upper curl, is generated in the recording paper 5 discharged onto the first discharge tray 61, the recording paper 5 is discharged in a state where the curve is corrected since the recording paper 5 comes into contact with the plurality of ribs 81, 81 . . . to expand toward both end portions along the width direction.
As described above, it is possible for the sheet discharge device 60 according to exemplary embodiment 1 to suppress that the posture of the recording paper 5 discharged to the first discharge tray 61 is disordered in a case of discharging the recording paper 5, compared to a case of not including the plurality of exhaust passages 80, 80, . . . that are provided in the wall surface 613 of the first discharge tray 61 and that are inclined to extend outward of both end portions along the width direction intersecting the discharging direction of the recording paper 5 toward the lower side of the wall surface 613.
That is, as shown in
The plurality of exhaust passages 80, 80, . . . consisting of slit portions inclined to extend outward of both end portions along the width direction intersecting the discharging direction of the recording paper 5 toward the lower side of the wall surface 613 in the vertical direction Z are provided in the wall surface 613 of the first discharge tray 61.
The plurality of exhaust passages 80, 80, . . . are formed through integral molding, for example, in a case where a member configuring the wall surface 613 of the first discharge tray 61 is molded.
A region of the wall surface 613 of the first discharge tray 61 present between the plurality of exhaust passages 80, 80, . . . may be configured by the identical flat surface as a surface of the wall surface 613, but may be in, for example, a rib shape that protrudes from the surface of the wall surface 613 as in exemplary embodiment 1 in order to reduce a contact resistance with the recording paper 5.
In a case where the recording paper 5 is discharged onto the first discharge tray 61 of the sheet discharge device 60 according to exemplary embodiment 2, air configuring the air sump 75 present below the recording paper 5 escapes into the apparatus body 1a via the plurality of exhaust passages 80, 80, . . . . For this reason, unlike exemplary embodiment 1, air flowing in the plurality of exhaust passages 80, 80, . . . does not flow from the lower side toward the upper side along the vertical direction Z along a longitudinal direction of the plurality of exhaust passages 80, 80, . . . , but flows from the surface toward the back surface (inner surface) of the wall surface 613 of the first discharge tray 61 via the plurality of exhaust passages 80, 80, . . . , and thereby it is possible to make the air configuring the air sump 75 present below the recording paper 5 quickly escape.
Since other components and operations are similar to the components and operations in exemplary embodiment 1 above, description thereof will be omitted.
Although the full-color image forming apparatus has been described in the exemplary embodiments, the sheet discharge device according to the exemplary embodiments of the present invention is not limited thereto. It is evident that the same can also be applied to a monochrome image forming apparatus, and it is evident that the same can also be applied to a finisher or the like which binds a sheet or which performs perforation processing or the like, in addition to the image forming apparatus.
(((1)))
A sheet discharge device comprising:
The sheet discharge device according to (((1))),
The sheet discharge device according to (((2))),
The sheet discharge device according to (((2))),
The sheet discharge device according to (((1))),
The sheet discharge device according to any one of (((1))) to ((5))),
An image forming apparatus comprising:
The foregoing description of the exemplary embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2023-093649 | Jun 2023 | JP | national |
