JP2014172702A - Paper feeding apparatus and image formation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeding apparatus and an image formation apparatus capable of smoothly moving an end fence with low cost and having excellent space-saving.SOLUTION: A paper feeding apparatus and an image formation apparatus include a paper arrangement part 50 arranging a paper bundle S, guide rails 52, 52 disposed along a paper carrying direction, a base member 53 disposed in the guide rails 52 along the paper carrying direction as relocatable, and an end fence 54 disposed in the base member 53 in a vertical direction and determining a position of a downstream end of the paper carrying direction of the paper bundle S. Two piece of the guide rails 52 are disposed in parallel, in which a cross-sectional shape thereof is one combining an upper side horizontal part 52a, a vertical part 52b and a lower side horizontal part 52c. In the base member 53, an upper side roller member 56 contacted to an upper side surface 52au of the upper side horizontal part 52a of the guide rail, and a lower side roller member 57 contacted to a lower side surface 52ad. The upper side roller member 56 is disposed in a center of the base member 53 and a center position of the lower side roller members 57, 58. The end fence 54 is disposed in a downstream side of a carrying direction of the base member 53.

Description

  The present invention relates to a sheet feeding device that supplies sheets one by one from a bundle of sheets arranged in a sheet placement unit to an image forming unit, and an image forming apparatus including the sheet feeding device.

  The sheet feeding device is provided with an end fence to regulate the position of the end surface of the sheet bundle on the downstream side in the sheet conveyance direction. When the paper is replenished, the end fence changes the position along the paper conveyance direction in accordance with the size of the replenished paper. For this reason, the end fence is configured to be able to move along the rails arranged in the paper arrangement portion where the paper bundle is arranged.

  Patent Document 1 describes that a paper guide mechanism is provided with an end fence so that front and back and double-sided printing of the paper can be performed, and the end fence can move along a long axis rail.

  Patent Document 2 describes a paper feed tray on which sheet materials are stacked, and a paper feed device that is slidably arranged so as to be able to contact and separate the sheet end portions of the sheet materials stacked on the paper feed tray. Yes.

  However, in the conventional paper feeding device, the end fence moves along a long guide member, and therefore when the vertical dimension of the end fence increases, when a force is applied to the tip during movement of the end fence, A large bending moment is generated in the guide member. Then, the guide member is deformed and the end fence cannot be moved smoothly.

  FIG. 6 is a schematic diagram showing a conventional paper feeder. In the paper feeding device 80, two rails 82 and 82 are installed below the tray bottom plate 81 along the paper transport direction. A base member 84 is slidably disposed on the rails 82, 82, and an end fence 83 is disposed on the base member 84 in the vertical direction. Here, the base member 84 can be moved while being in surface contact with the rails 82, 82, and the end fence 83 can be moved along the sheet conveying direction in accordance with the size of the sheet bundle S.

  In such a sheet feeding device 80, when the end fence 83 is moved, a large bending moment M is applied to the rail 82. When the end fence 83 is moved, the user pushes and operates the upper portion of the end fence 83, so the moment M increases as the end fence length “L” (FIG. 6B) increases. The rails 82 and 82 are bent with respect to the attachment portion with the base member 84, and the end fence 83 also falls down (indicated by a broken line in FIG. 6B).

  In order to avoid such a situation, it is necessary to operate the sheet feeder 80 at the lower part of the end fence so that the user does not bend the rails 82 and 82. In addition, although a mechanism including a slide rail mechanism can be adopted for the movement of the end fence 83, there is a problem that the price is high and rattling that is peculiar to the slide rail mechanism occurs.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a paper feeding device that can move an end fence smoothly and has excellent space saving performance with a low-cost configuration.

  A sheet feeding device according to the present invention includes a sheet arranging unit that arranges a sheet bundle composed of a plurality of sheets used for image formation, and is arranged in a lower position of the sheet bundle along the sheet conveying direction inside the sheet arranging unit. A guide rail, a base member disposed on the guide rail so as to be capable of changing a position along the sheet conveyance direction, and a downstream end portion of the sheet bundle disposed in a vertical direction on the base member in the sheet conveyance direction. In the sheet feeder provided with an end fence for determining a position, the guide rails are arranged in parallel, and the cross-sectional shape is a combination of a horizontal portion extending in the horizontal direction and a vertical portion extending in the vertical direction. The base member includes an upper roller member that contacts an upper side surface of the horizontal portion of the guide rail, and a lower roller member that contacts a lower side surface of the horizontal portion. Material and lower roller member may be arranged in different locations along the sheet conveyance direction.

  According to the present invention, an end fence can be moved smoothly, and a paper feeding device excellent in space saving can be provided at a low price.

1 is a schematic diagram illustrating an image forming apparatus to which a paper feeding device according to the present invention is applied. It is a figure which shows the paper feeder concerning embodiment of the paper feeder concerning this invention, (a) is a right view, (b) is sectional drawing equivalent to the bb line in (a). It is a schematic diagram which shows the guide rail and base part of the paper feeder. It is a schematic diagram which shows the contrast of a guide rail and a base part. It is a schematic diagram which shows the movement state of the end fence of the paper feeder. It is a schematic diagram which shows the conventional paper feeder.

  A sheet feeding device and an image forming apparatus according to an embodiment for carrying out the present invention will be described. First, an overall configuration of an image forming apparatus to which the sheet feeding device according to the embodiment can be applied will be described. FIG. 1 is a schematic diagram illustrating an image forming apparatus to which a sheet feeding device according to an embodiment can be applied. As shown in FIG. 1, the image forming apparatus 30 includes an image forming apparatus main body 40 that performs image forming processing, and a paper feeding device 10 that is connected to one side surface of the image forming apparatus main body 40.

  The image forming apparatus main body 40 is, for example, a printer, a multi-function machine or the like provided with an electrophotographic image forming unit. Further, the image forming unit of the image forming apparatus main body 40 is not limited to the electrophotographic type, but may be of another type such as an ink jet type. Furthermore, although the image forming apparatus main body 40 and the paper feeding apparatus 10 have been described as separate apparatuses, the paper feeding apparatus may be disposed in the image forming apparatus main body.

  2A and 2B are diagrams illustrating a paper feeding device according to an embodiment of the paper feeding device according to the present invention, in which FIG. 2A is a right side view, and FIG. 2B is a cross-sectional view corresponding to the line bb in FIG. It is. The sheet feeding device 10 includes a sheet placement unit 50 that stores a sheet bundle S in which sheets are placed in an overlapping manner, and a suction belt unit 60. A tray bottom plate 51 on which the sheet bundle S is stacked is disposed below the sheet placement unit 50, and the tray bottom plate 51 is driven in the vertical direction by a driving unit (not shown).

  Further, as shown in FIG. 2A, the sheet feeding device 10 includes a flying fan 65, blows sheet floating air, and floats the sheets on the sheet bundle S to a position directly below the suction belt unit 60. The suction belt unit 60 conveys the uppermost sheet S1 that is lifted from the sheet bundle S composed of a plurality of stacked sheets one by one. Thus, the flying fan 65 and the suction belt unit 60 constitute a paper transport mechanism. The transport mechanism is not limited to this example, and may be another type of mechanism. Other methods include a friction separation method, for example, a combination of a feed roller and a pad, a combination of a feed roller and a reverse roller (FRR method), and a roll feeder method (RF method). Moreover, an electrostatic adsorption system, an air adsorption system, etc. can also be adopted.

  As shown in FIG. 2A, the suction belt unit 60 includes a conveyance belt 63 that is wound around two rollers 61 and 62. Of the rollers 61 and 62, the roller 61 is rotationally driven by a rotational driving means (not shown), the conveyor belt 63 is rolled, and the roller 62 rotates according to these. Further, a suction device 64 is disposed in the suction belt unit 60, sucks air S <b> 1 floated by sucking air from a suction hole (not shown) of the transport belt 63, and transports the paper S <b> 1 by rolling of the transport belt 63. To do.

  When transporting paper, the tray bottom plate 51 is raised to a predetermined position, and the flying blower 65 blows air toward the front end face of the sheet bundle S stacked on the tray bottom plate 51. This air causes the uppermost sheet S1 to float up to the height of the suction belt unit 60. Then, the suction device 64 is actuated so that the sheet S 1 is attracted to the transport belt 63 and transported to the image forming apparatus main body 40.

  In the paper feeding device 10, two guide rails 52 and 52 are arranged at the lower position of the tray bottom plate 51 inside the paper arrangement unit. And the base member 53 which attached the end fence 54 to the guide rails 52 and 52 is arrange | positioned so that a position change is possible. The guide rails 52, 52 are arranged in parallel at a predetermined interval along the paper conveyance direction. The guide rail 52 has a cross-sectional shape that combines a horizontal portion extending in the horizontal direction and a vertical portion extending in the vertical direction. That is, the guide rail 52 is attached to the bottom plate 50a of the paper placement unit 50 and is disposed on the lower horizontal part 52c, the vertical part 52b rising vertically from the lower horizontal part 52c, and horizontally from the vertical part 52b. And an upper horizontal portion 52a that extends.

  The upper horizontal portions 52a and 52a of the two guide rails 52 and 52 are arranged in parallel at a predetermined interval. Since the guide rails 52 and 52 have such a cross-sectional shape, the guide rails 52 and 52 have a large section modulus and a high rigidity against bending in the longitudinal direction.

  The base member 53 is disposed between the guide rails 52 and 52 so as to be movable in the paper transport direction. The base member 53 includes an upper roller member 56 that contacts the upper side surface 52au of the upper horizontal portion 52a of the guide rail, and two lower roller members 57 and 58 that contact the lower side surface 52ad of the upper horizontal portion 52a.

  The base member 53 includes two vertical side surfaces 53a and 53a that are formed along the paper conveyance direction and face the guide rails 52 and 52. The upper roller member 56 and the lower roller members 57 and 58 are provided with the vertical side surfaces 53a and 53a. It is arranged so that it can rotate. The upper roller member 56 and the lower roller members 57 and 58 are arranged at different locations along the paper transport direction. In this example, the upper roller member 56 is disposed at the center position in the transport direction of the base member 53. Further, the upper roller member 56 is arranged at the center position in the paper transport direction of the arrangement of the lower roller members 57 and 58 with respect to the upper roller member 56. Therefore, as shown in FIG. 5, the distance between the center of the upper roller member 56 and the center of the lower roller members 57 and 58 is equal (indicated by “E” in FIG. 5).

  Here, if the upper roller member 56 is supported by the shaft 56a and the lower roller members 57 and 58 are supported by the shafts 57a and 58a, the base member 53 holds the shaft 56a and the shafts 57a and 58a. A hole is formed. In the sheet feeding device according to the present embodiment, by providing the above-described configuration, it is possible to increase the distance between the hole portion of the base member 53 that supports the shaft 56a and the hole portion of the base member 53 that supports the shafts 57a and 58a. (Indicated by “D” in FIG. 3). For this reason, the diameter of the roller of each roller member can be reduced, and the height dimension “F” of the base member 53 including the roller member can be reduced.

  On the other hand, as shown in FIG. 4, when the upper roller members 71 and 72 and the lower roller members 73 and 74 are disposed on the base member 53 at positions facing each other, the shafts 71 a and 72 a of the roller members are arranged. The interval between the holes of the base member 53 that holds 73a and 74a is reduced. This state is indicated by “D1” in FIG. 4 (“D1”> “D”). In other words, the distance between the holes that hold the upper roller member 71 and the lower roller member 73 facing each other is as small as D1 in FIG. 4, and the strength cannot be maintained. For this reason, even if the diameter of the roller of the roller member is reduced, the strength cannot be maintained.

  As described above, in the sheet feeding device 10 according to the embodiment, the interval between the hole portions for holding the upper roller member 56 and the lower roller members 57 and 58 formed in the base member 53 can be widened. For this reason, by reducing the diameter of the roller of the roller member, the height dimension “F” can be reduced while maintaining the strength of the base member 53.

  Furthermore, in the sheet feeding device 10 according to the embodiment, as shown in FIGS. 2B and 5, the end fence 54 is downstream of the center position of the base member 53 in the sheet conveyance direction, that is, downstream of the base member 53. The end is connected to a position shifted by the dimension “d”. For this reason, the paper placement section 50 can be made smaller than when the end fence 54 is placed at the center position of the base member 53. That is, assuming that the end fence 54 is arranged at the center of the base member 53, when the end fence 54 is pulled out, a portion of the base member 53 downstream from the end fence 54 is prevented from protruding beyond the end fence 54. it can.

  Further, in the sheet feeding device 10 according to the embodiment, the upper roller member 56 is set at the center position of the base member 53, and the end fence 54 is disposed at the end of the base member 53. Therefore, as shown in FIG. 5, when the end fence 54 is moved in the direction of the arrow “L” in order to move the end fence 54, a moment “B” acts on the joint “A” to the base member 53. . Conversely, when the end fence 54 is moved in the direction of the arrow “R”, a moment “C” is generated in “A”.

  In the sheet feeding device 10 according to the embodiment, the end fence 54 is arranged at the end on the downstream side from the center of the base member 53. For this reason, when any force is applied to the end fence 54 to the end fence 54 when the base member 53 is moved, a force is applied in the direction in which the base member 53 is inclined. However, in the paper feeder 10 according to the embodiment, the force is evenly distributed from the center “A” of the upper roller member 56. For this reason, the unnatural movement of the base member 53 due to the bias of force can be prevented, and the base member 53 can be moved smoothly.

  The same effect can be obtained even if the positions of the upper and lower roller members are turned upside down. Here, when the gap between the guide rails 52 and 52 and the vertical side surfaces 53a and 53a of the base member 53 is reduced, rattling between the base member 53 and the guide rails 52 and 52 can be prevented. This is effective in the paper transport direction and in the direction perpendicular to the paper transport direction. For this reason, the base member 53 can be held without rattling in all directions.

10: paper feeder 30: image forming apparatus 40: image forming apparatus main body 50: paper placement unit 50a: bottom plate 51: tray bottom plate 52: guide rail 52a: upper horizontal portion 52ad: lower side surface 52au: upper side surface 52b: vertical portion 52c : Lower horizontal portion 53: Base member 53 a: Vertical side surface 54: End fence 56: Upper roller member 56 a: Shaft 57, 58: Lower roller member 57 a, 58 a: Shaft 60: Suction belt unit 61, 62: Roller 63: Conveyor belt 64: Suction device 65: Blower for levitation

JP 2000-318934 A JP 2009-051630 A

Claims (5)

A sheet placement section for placing a sheet bundle of a plurality of sheets to be used for image formation; a guide rail disposed in a lower position of the sheet bundle in the sheet placement section along the sheet transport direction; and the guide rail A base member arranged to be capable of changing its position along the paper conveyance direction, and an end fence arranged vertically on the base member and defining a position of a downstream end of the paper bundle in the paper conveyance direction. In the paper feeder,
Two guide rails are arranged in parallel, and the cross-sectional shape is a combination of a horizontal portion extending in the horizontal direction and a vertical portion extending in the vertical direction,
The base member includes an upper roller member that contacts an upper surface of the horizontal portion of the guide rail, and a lower roller member that contacts a lower surface of the horizontal portion,
The sheet feeding device, wherein the upper roller member and the lower roller member are arranged at different locations along the sheet conveyance direction.   The sheet feeding device according to claim 1, wherein the end fence is disposed downstream of a center position of the base member in the sheet conveyance direction.   The base member is disposed between the guide rails, and the upper roller member and the lower roller member are disposed on a vertical side surface of the base member along the sheet conveyance direction. The sheet feeding device according to claim 1 or 2.   The base member is provided with one upper roller member and two lower roller members, and the upper roller member is disposed at a central position of the two lower roller members. The sheet feeding device according to 3.   An image forming apparatus comprising: the sheet feeding device according to claim 1; and an image forming unit that forms an image on a sheet conveyed by the sheet feeding device.