JP2016177295A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the strength of a bottom surface of an image reading unit, and to suppress the occurrence of a paper jam while ejecting a paper sheet to a paper sheet ejection tray provided between the image reading unit and an image forming unit.SOLUTION: An image forming apparatus 10 comprises an image reading unit 20 and an image forming unit 30. The image forming unit 30 is disposed under the image reading unit 20. The image forming unit 30 is configured to have a space 51 for providing a paper sheet ejection tray 50 between the image forming unit 30 and the image reading unit 20. A bottom surface 23 of the image reading unit 20 has a plurality of ribs 24 formed in a direction along a paper sheet ejecting direction 91, and defines a top surface of the space 51.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image forming apparatus having a so-called in-cylinder discharge shape.

  An image forming unit is disposed under the image reading unit, and the image forming unit is configured to have a space for providing a paper discharge tray for storing paper after image forming processing between the image reading unit and the image reading unit. An image forming apparatus having a so-called in-cylinder discharge shape is known.

  Among image forming apparatuses having such an in-cylinder discharge shape, the height of the space for providing a paper discharge tray is reduced for the purpose of downsizing the image forming apparatus, and the paper is placed on the bottom surface of the image reading unit. Some of them are discharged to a paper discharge tray while being lined up (see, for example, Patent Document 1).

  On the other hand, the bottom plate of the housing of the image reading unit is thinned for cost reduction. However, since it is necessary to increase the strength to support the internal device of the image reading unit, the rib is formed with a sheet metal. May be provided.

JP 2010-74625 A

  However, when there is a rib provided in a direction other than the direction along the paper discharge direction to the paper discharge tray, and the upstream end of the rib in the paper discharge direction is the first sheet discharged from the image forming unit. In the case where it is on the downstream side from the position where it can come into contact with the bottom surface of the image reading section, the leading edge of the paper may be caught by the rib, and paper jam may occur.

  In the image forming apparatus described in Cited Document 1, a plurality of pairs of ribs and grid-like ribs are provided on the bottom surface of the image reading unit so that the interval in the paper width direction increases toward the downstream side in the paper discharge direction. If the leading end of the paper hits a rib in the direction perpendicular to the paper discharge direction, there is a risk of paper jamming. Further, depending on how the paper is curled, there is a risk that paper jams will occur due to the leading edge of the paper being caught by a rib whose interval in the paper width direction becomes wider downstream in the paper discharge direction.

  An object of the present invention is to increase the strength of the bottom surface of the image reading unit, and to suppress the occurrence of a paper jam at the time of paper discharge to a paper discharge tray provided between the image reading unit and the image forming unit. An object of the present invention is to provide an image forming apparatus capable of performing the above.

  An image forming apparatus according to the present invention includes an image reading unit that performs an image reading process of reading an image of a document placed on a document table, and the bottom surface of the image reading unit includes at least one rib protruding downward. ing. The rib has a flat portion parallel to the bottom surface and a slope portion that connects the periphery of the flat portion and the bottom surface. The slope portion is inclined in a direction of gradually descending from the upstream side to the downstream side in the discharge direction of the paper conveyed through the paper conveyance path.

  In this configuration, the strength of the bottom surface of the image reading unit is increased by the rib. When the upper surface of the space where the paper is discharged from the image forming unit is configured by the bottom surface of the image reading unit, the rib protrudes into the space, but the flat portion of the rib is from the upstream side toward the downstream side in the paper discharge direction. The slope portion that is inclined in a gradually descending direction is connected to the bottom surface so that the end portion of the sheet discharged from the image forming portion is not caught by the rib.

  According to the present invention, it is possible to increase the strength of the bottom surface of the image reading unit, and to suppress the occurrence of a paper jam at the time of paper discharge to the paper discharge tray provided between the image reading unit and the image forming unit. can do.

1 is a front sectional view showing a schematic configuration of an image forming apparatus according to an embodiment of the present invention. (A) is a bottom view of the image reading unit, (B) is a side view of a part of the image reading unit shown in (A), and (C) is an enlarged view of a rib shown in (B). It is. It is a front sectional view showing a schematic configuration of an image forming apparatus according to another embodiment.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated based on drawing.

  As illustrated in FIG. 1, the image forming apparatus 10 includes an image reading unit 20, an image forming unit 30, and a paper feeding unit 40.

  The image reading unit 20 is disposed above the image forming apparatus 10, an image forming unit 30 is disposed below the image reading unit 20, and a paper feeding unit 40 is disposed below the image forming unit 30.

  The image reading unit 20 includes an automatic document feeder (ADF: Automatic Document Feeder) 21 and a scanner unit 22.

  As an example, the scanner unit 22 includes a CIS (Contact Image Sensor) 221 that is a moving member that reciprocates along the document table. The scanner unit 22 includes a first scanning unit on which a light source and a mirror as a moving member are mounted, a second scanning unit on which other similar mirrors are mounted, an imaging lens and a CCD ( It can also be configured to have a Charge Coupled Device) sensor.

  The scanner unit 22 performs an image reading process of generating image data by reading an image of a document conveyed by the ADF 21 via the document table or a document placed on the document table by manual operation.

  The paper feed unit 40 stores paper and supplies the paper to the image forming unit 30 one by one. Examples of the paper include recording media such as plain paper, photographic paper, and OHP film.

  The image forming unit 30 includes an electrophotographic process unit 31 and a fixing device 32, and executes an electrophotographic image forming process on a sheet.

  Specifically, the electrophotographic process unit 31 includes a photosensitive drum 311, a charger 312, an optical scanning device 313, a developing device 314, and a transfer device 315. The charger 312 charges the peripheral surface of the photosensitive drum 311 to a predetermined potential. The optical scanning device 313 forms an electrostatic latent image by scanning the peripheral surface of the photosensitive drum 311. The developing device 314 supplies toner (developer) to the peripheral surface of the photosensitive drum 311 to develop the electrostatic latent image into a toner image. The transfer unit 315 transfers the toner image onto a sheet. The fixing device 32 firmly fixes the toner image to the paper by heating and pressurizing the paper carrying the toner image.

  The image forming unit 30 has a partial horizontal cross-sectional area that reads the image so that a space 51 is provided between the image reading unit 20 and a paper discharge tray 50 for storing the paper after the image forming process. It is formed smaller than the portion 20. As described above, the image forming apparatus 10 has a so-called in-cylinder discharge shape. The space 51 is vertically sandwiched between the bottom surface 23 of the housing of the image reading unit 20 and the paper discharge tray 50.

  The sheet supplied from the sheet feeding unit 40 is conveyed through a sheet conveyance path 52 that passes through the electrophotographic process unit 31 and the fixing device 32, and the surface on which the toner image is fixed from the sheet discharge unit 33 to the sheet discharge tray 50. Is discharged with the bottom side down.

  The sheet conveyance path 52 extends in a substantially vertical direction in a region from the paper feeding unit 40 to the image forming unit 30 and is curved so as to approach the horizontal direction near the upstream side of the paper discharge unit 33. However, in order to prevent a paper jam due to a sharp curve of the paper transport path 52, the paper discharged from the paper discharge unit 33 is discharged slightly upward. As a result, the sheet is discharged along the bottom surface 23 facing the space 51 of the image reading unit 20 and is stored in the sheet discharge tray 50. In this embodiment, the bottom surface 23 is arranged in the horizontal direction.

  The bottom plate of the housing of the image reading unit 20 is made of sheet metal.

  As shown in FIG. 2, the bottom surface 23 of the image reading unit 20 has a plurality of ribs 24. The ribs 24 are formed in a direction along the paper discharge direction 91 from the paper discharge unit 33 to the paper discharge tray 50.

  The rib 24 is provided from a position upstream from a position where the paper discharged from the image forming unit 30 can first contact the bottom surface 23 of the image reading unit 20 in the paper discharge direction 91 to the vicinity of the downstream end of the bottom surface 23. ing. In this embodiment, the ribs 24 are provided over the entire bottom surface 23 in the paper discharge direction 91.

  As an example, the rib 24 has a rectangular shape in a bottom view. The rib 24 has a flat surface portion 241 parallel to the bottom surface 23, and an inclined surface portion 242 that connects the periphery of the flat surface portion 241 and the bottom surface 23. It is preferable that an angle A1 formed by the flat surface portion 241 and the inclined surface portion 242 positioned between the adjacent ribs 24 is 135 degrees or more and less than 180. Since the slope portion 242 is gently inclined with respect to the bottom surface 23, damage to the sheet due to the corner portion formed by the flat portion 241 and the slope portion 242 is suppressed.

  According to the image forming apparatus 10, the rib 24 is provided on the bottom surface 23 of the image reading unit 20, and the rib 24 is configured such that the sheet discharged from the image forming unit 30 in the sheet discharge direction 91 first is the bottom surface 23 of the image reading unit 20. Since it is provided from a position on the upstream side to a position near the downstream end of the bottom surface 23 from the position where it can contact, the strength of the bottom surface 23 of the image reading unit 20 is increased.

  Further, the rib 24 is formed in a direction along the paper discharge direction 91 to the paper discharge tray 50, and the upstream side end of the rib 24 in the paper discharge direction 91 is the first sheet discharged from the image forming unit 30. Since the sheet is disposed on the upstream side from the position where it can contact the bottom surface 23, the sheet discharged to the sheet discharge tray 50 is not caught by the rib 24.

  Furthermore, since no ribs other than the ribs 24 are provided on the bottom surface 23 of the image reading unit 20, the occurrence of a paper jam due to the paper discharged to the paper discharge tray 50 coming into contact with the bottom surface 23 is suppressed.

  Further, even if the paper discharged from the paper discharge unit 33 to the space 51 comes into contact with the bottom surface 23 of the image reading unit 20, the paper jam hardly occurs, so that the height of the space 51 can be reduced. Therefore, the image forming apparatus 10 can be reduced in size.

  As shown in FIG. 3, the image forming apparatus 10 </ b> A according to another embodiment is configured such that the bottom surface 23 </ b> A of the image reading unit 20 is inclined in a direction that becomes higher toward the downstream side of the paper discharge direction 91 with respect to the horizontal plane. Thus, the configuration is the same as that of the image forming apparatus 10. As an example, the height difference between both ends of the bottom surface 23 </ b> A in the paper discharge direction 91 is about 10 mm to 15 mm.

  The flat portion 241 of the rib 24 is parallel to the bottom surface 23A. That is, the flat portion 241 of the rib 24 is also inclined in a direction that becomes higher toward the downstream side of the paper discharge direction 91 with respect to the horizontal plane.

  On the other hand, the inner surface of the bottom plate of the housing of the image reading unit 20 is arranged in the horizontal direction. As a result, the internal device of the scanner unit 22 is supported on a horizontal plane and executes an image reading process with high accuracy.

  The image forming process executed by the image forming apparatus 10 </ b> A includes a fixing process in which the sheet is heated by the fixing device 32, as with the image forming apparatus 10. The sheet heated in the fixing process is discharged to the sheet discharge tray 50, and a part of the heated air around the fixing device 32 is guided to the space 51 through the sheet conveyance path 52. Further, since the bottom surface 23A of the image reading unit 20 is inclined with respect to the horizontal plane in a direction that becomes higher toward the downstream side in the paper discharge direction 91, the heated air is downstream in the paper discharge direction 91 along the bottom surface 23A. To be easily discharged outside the space 51. For this reason, the temperature rise in the space 51 is suppressed.

  Therefore, according to the image forming apparatus 10 </ b> A, the strength of the bottom surface 23 </ b> A of the image reading unit 20 can be increased and the sheet discharge tray 50 provided between the image reading unit 20 and the image forming unit 30 can be provided. In addition to being able to suppress the occurrence of paper jams during paper discharge, it is also possible to achieve an effect that the temperature rise in the space 51 can be suppressed.

  Note that the flat portion 241 of the rib 24 is preferably narrow as long as the sheet is not damaged. When the flat surface portion 241 is narrow, the sheet is less likely to be attracted to the flat surface portion 241 due to the static electricity of the paper, so that the paper is easily transported smoothly, and the stacking failure of the paper onto the paper discharge tray 50 is suppressed. It is.

  Moreover, the rib 24 is not limited to being provided in plural on the bottom surfaces 23 and 23A, and may be only one.

  Furthermore, it is not an essential requirement that the image reading unit 20 includes the ADF 21. Furthermore, the image forming unit 30 can be configured to include a plurality of electrophotographic process units 31 corresponding to a plurality of different hues. Further, the image forming process executed by the image forming unit 30 does not necessarily have to be an electrophotographic system.

  The above description of the embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

DESCRIPTION OF SYMBOLS 10,10A Image forming apparatus 20 Image reading part 23,23A Bottom face 24 Rib 30 Image forming part 31 Electrophotographic process part 32 Fixing device 50 Paper discharge tray 51 Space 91 Paper discharge direction

Claims (6)

An image reading unit for performing an image reading process for reading an image of a document placed on a document table;
The bottom surface of the image reading unit has at least one rib protruding downward,
The rib is a flat portion parallel to the bottom surface and a slope portion that continues the periphery of the flat portion and the bottom surface, and is upstream from the downstream in the discharge direction of the paper conveyed through the paper conveyance path. Forming apparatus having a slope portion inclined in a direction of gradually descending toward. An image forming unit that is disposed under the image reading unit and performs image forming processing on a sheet, and is configured to have a space between the image reading unit and a sheet from which the sheet is discharged. An image forming unit,
The image forming apparatus according to claim 1, wherein the bottom surface constitutes an upper surface of the space.   The image forming apparatus according to claim 2, wherein the space is a space in which a paper discharge tray for storing the paper discharged from the image forming unit is disposed.   The rib is formed in a range from the upstream position in the paper discharge direction to the downstream side in the discharge direction from the position where the end of the paper discharged from the image forming portion on the bottom surface first contacts. The image forming apparatus according to claim 2 or 3.   5. The image forming apparatus according to claim 1, wherein the bottom surface is inclined at least at a portion where the rib is formed in a direction that becomes higher with respect to a horizontal plane toward a downstream side in the paper discharge direction. 6.   The image forming apparatus according to claim 1, wherein the bottom surface is formed of a metal plate.

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