JP2008094529A - Bearing structure and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing structure capable of reducing operational failure caused between a sliding part and a sliding object part while sliding. <P>SOLUTION: A rotary shaft 66 is rotatably supported at its both ends by bearings 70a and 70b. The bearings 70a and 70b are supported by pressing springs 72a and 72b, and the bearings 70a and 70b energized in the Z direction by the pressing springs 72a and 72b, are guided in the Z direction by guide parts 74a and 74b slidably supporting the bearings 70a and 70b. The bearings 70a and 70b form sliding surfaces 82a and 82b slidingly contacting with the guide parts 74a and 74b, and slide on the guide parts 74a and 74b. The sliding surfaces 82a and 82b are formed as a curved surface in the sliding direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a roll device, a sheet supply device, and an image forming apparatus having the roll device.

  For example, Patent Document 1 discloses a sliding member and a sliding member by sliding a sliding member made of a hard second material on a sliding member made of a soft first material. Disclosed is a sliding device for an electrophotographic copying machine in which both wear is reduced.

JP-A-1-37566

  The present invention has been made from the background described above, and an object of the present invention is to provide a roll apparatus that can reduce malfunctions that occur between a sliding part and a sliding part during sliding.

  In order to achieve the above object, a roll apparatus according to the present invention includes a roll body, a rotating shaft provided with the roll body, a bearing that rotatably supports the rotating shaft, and the bearing sliding in one direction. It has a guide part which guides freely, and a pressing member which presses the bearing in one direction, and a sliding surface with the guide part of the bearing is formed in a curved surface shape with respect to the sliding direction.

  Preferably, a contact surface of the guide portion with the bearing is formed in a flat shape.

  Preferably, a sliding surface of the bearing with the guide portion is formed in a spherical shape.

  Preferably, the guide portion is formed so as to surround a surface other than the sliding direction of the bearing.

The present invention includes a sheet feeding device having the above-described roll device.
Preferably, only one roll device is disposed at a position facing the central portion of the sheet in a direction orthogonal to the sheet supply direction.

  The present invention includes an image forming apparatus having the above sheet supply apparatus.

  According to the roll device of the present invention, the sliding surface with the bearing guide portion is formed in a curved surface with respect to the sliding direction, and thus occurs between the sliding portion and the sliding portion during sliding. Malfunctions can be reduced.

Embodiments of the present invention will be described below.
FIG. 1 shows an outline of an image forming apparatus 10 according to an embodiment of the present invention.

  The image forming apparatus 10 includes an image forming apparatus main body 12, an image forming unit 14 is mounted in the image forming apparatus main body 12, and a discharge unit 16 is provided on the upper portion of the image forming apparatus main body 12. A paper feed unit 18 is disposed below the image forming apparatus main body 12. In addition, a sheet conveyance path 17 for conveying sheets is formed in the image forming apparatus main body 12, and the sheet conveyance path 17 has a reverse path 50 as a conveyance path for double-sided printing described later.

  The paper feed unit 18 has a paper feed cassette 20, paper feed rolls 22 a, 22 b, and a separating roll 23, in which a sheet as a transfer material is stored and which can be pulled out from the image forming apparatus main body 12. The paper loaded in the paper feed cassette 20 is separated and fed to the registration roll 24 by the cooperation of the paper roll 22b and the separating roll 23.

  On the downstream side of the registration roll 24, an image carrier 28 and a transfer device 36 of a process cartridge (developing cartridge) 46, which will be described later, face each other, and a fixing device 40 is further provided on the downstream side thereof.

  Accordingly, the sheet fed from the sheet feeding cassette 20 of the sheet feeding unit 18 to the sheet conveying path 17 by the sheet feeding rolls 22a and 22b is temporarily stopped by the registration roll 24, and the image carrier 28 and the transfer device are timed. The developer image is transferred through the space 36, the transferred developer image is fixed by the fixing device 40, and discharged to the discharge portion 16 by the discharge roll 26.

  However, in the case of duplex printing, it is returned to the duplex printing unit 48 as duplex printing means. That is, the double-sided printing unit 48 is divided into two forks before the discharge roll 26, and a switching claw (not shown) is provided in the divided part, and double-sided printing returning from the divided part to the resist roll 24. A reverse path 50 is formed as a transfer path. The reversing path 50 is provided with transport rolls 52a to 52c. In double-sided printing, a switching claw (not shown) is switched to the side that opens the reversing path 50, and the discharge roll 26 is in front of the rear end of the sheet. At this time, the discharge roll 26 is reversed, the sheet is guided to the reverse path 50, and is discharged to the discharge portion 16 through the resist roll 24, the transfer device 36 and the image carrier 28 and through the fixing device 40.

  The image forming means 14 is of an electrophotographic type, and includes an image carrier 28 made of a photoconductor, a charging device 30 made of, for example, a charging roll for uniformly charging the image carrier 28, and charging by the charging device 30. An optical writing device 32 that writes a latent image on the image carrier 28 by light, a developing device 34 that visualizes a latent image of the image carrier 28 formed by the optical writing device 32, and a developing device 34 For example, a transfer device 36 that transfers the developer image onto the paper, a cleaning device 38 that cleans the developer remaining on the image carrier 28, and a developer image on the paper transferred by the transfer device 36 is fixed on the paper. The fixing device 40 includes a pressure roll and a heating roll. The optical writing device 32 is composed of, for example, a scanning laser exposure device, and traverses the process cartridge 46 to form a latent image on the image carrier 28. The cleaning device 38 includes a cleaning blade 42 that comes into contact with the image carrier 28 and a developer recovery unit 44 that stores the developer scraped off by the cleaning blade 42. The optical writing device 32 may use an LED or a surface emitting laser as another embodiment.

  In the process cartridge 46, the image carrier 28, the charging device 30, the developing device 34, and the cleaning device 38 are integrated, and these can be replaced as a unit.

  The paper feed cassette 20 described above is provided with a paper transport path 60. When a plurality of paper cassettes are arranged in multiple stages by this paper transport path 60, paper fed from other paper feed cassettes arranged on the lower side is transported.

  Further, a manual feed unit 54 as a manual paper feed unit is disposed on a side surface (left side surface in FIG. 1) of the image forming apparatus main body 12. The manual feed unit 54 includes a manual feed tray 56 for storing paper and a manual pick roll 58, and the paper stored in the manual feed tray 56 is picked by the rotation of the manual feed pick roll 58. The paper fed from the manual pick roll 58 is discharged between the registration roll 24, the transfer device 36 and the image carrier 28, and the fixing device 40, as in the paper fed from the paper feeding unit 18. To be discharged.

A manual feed tray 56 provided in the manual feed unit 54 opens when it rotates in the direction of the arrow shown in FIG. 1 and is supported by the image forming apparatus main body 12 so that it can be opened and closed.
The manual feed tray 56 is provided with a side guide 62 and a manual feed roll 64. The side guide 62 is movably provided in accordance with the size of the paper so as to contact the side surface of the paper stored in the manual feed tray 56. The manual feed roll 64 is disposed at a position facing the manual feed roll 58, and the paper stored in the manual feed tray 56 is separated and fed by the cooperation of the manual feed roll 64 and the manual feed roll 58. It has become.

In FIG. 2, the details of the manual feed roll 64 are shown.
The manual feed roll 64 is provided in a manual feed roll device 68 to be described later, and the manual feed roll device 68 is disposed on the manual feed tray 56.

3 to 6, details of the manual feed roll device 68 and the bearings 70a and 70b are shown.
3 is a plan view of the manual sheeting roll device 68, FIG. 4A is a cross-sectional view taken along the line AA shown in FIG. 3, and FIG. 4B is a line taken along the line BB shown in FIG. FIG. 4C is a cross-sectional view taken along the line CC of FIG. As shown in FIGS. 3 to 4, the rotation axis direction is the X direction, and the directions orthogonal to the axial direction are the Y and Z directions.

The manual feed roll 64 is attached to the rotary shaft 66. The both ends of the rotating shaft 66 are rotatably supported by bearings 70a and 70b.
Further, bearing cylinders 80a and 80b are formed in the bearings 70a and 70b, and a rotating shaft 66 is inserted into the bearing cylinders 80a and 80b.

The bearings 70a and 70b are pressed and supported by the pressing springs 72a and 72b in the Z direction. The bearings 70a and 70b urged in the Z direction by the pressing springs 72a and 72b are slidably guided in the Z direction by the guide portions 74a and 74b. Guide portions 76a and 76b are formed in the guide portions 74a and 74b, and the operations of the bearings 70a and 70b in the Y direction are restricted by the guide portions 76a and 76b. The bearings 70a and 70b Sliding surfaces 82a and 82b that are in sliding contact with 74b are formed, and the guide portions 74a and 74b are slid in the Z direction. The sliding surfaces 82a and 82b are formed in a curved shape with respect to the sliding direction.

  In the following description, for example, when any of a plurality of components such as the bearings 70a and 70b is shown without being specified, it may be simply abbreviated as the bearing 70 or the like.

The manual feed roll device 68 may be slightly tilted from the X direction to the Z direction as shown in FIG. 6A when the urging forces of the two pressing springs 72a and 72b are not balanced.
Since the sliding surface 82 of the bearing 70 with the guide portion 74 is formed in a curved surface shape, the bearing 70 is in smooth contact with the guide portion 74 even if the manual feed roll device 68 is tilted from the X direction to the Z direction. Yes.

  As shown in FIG. 6B, compared to the case where the sliding surface with the guide portion 74 of the bearing 70 is formed in a flat surface, when the sliding surface is formed in a flat surface, the guide portion is in the D portion. Since the contact is made so as to abut against 74, the sliding operation of the bearing 70 is better when the sliding surface is formed into a curved surface.

Next, a second embodiment according to the present invention will be described.
Hereinafter, the same reference numerals are given to the components described in the first embodiment, and duplicate descriptions are omitted.

7 and 8 show details of the manual feed roll device 88 according to the second embodiment.
7A is a plan view of the manual feed roll device 88, FIG. 7B is a cross-sectional view taken along line EE shown in FIG. 7A, and FIG. It is FF sectional view taken on the line shown to B). As shown in FIGS. 7A to 7C, the rotation axis direction is the X direction, and the directions orthogonal to the axial direction are the Y and Z directions.

The manual feed roll device 88 includes a manual feed roll 64, a rotary shaft 66 on which the manual feed roll 64 is mounted, and bearings 90a and 90b that rotatably support both ends of the rotary shaft 66.
The entire surfaces of the bearings 90a and 90b are formed in a spherical shape.
The bearings 90a and 90b are pressed and supported by the pressing springs 72a and 72b in the Z direction. The bearings 90a and 90b urged in the Z direction by the pressing springs 72a and 72b are guided in the Z direction by the guide portions 94a and 94b. The rotary shaft 66 supported by the bearings 90a and 90b passes through the rotary shaft gaps 96a and 96b formed in the guide portions 94a and 94b.

The guide portions 94a and 94b are formed so as to surround the surfaces of the bearings 90a and 90b in the X and Y directions, and restrict the movement of the bearings 90a and 90b in the X and Y directions.
The bearings 90a and 90b slide in the Z direction on the inner surfaces of the guide portions 94a and 94b.
Further, the pressing springs 72 a and 72 b are arranged so that the centers thereof are located almost directly below the center of gravity of the bearing 90.

Since the sliding surface of the bearing 90 with the guide portion 94 is formed in a spherical shape, as shown in FIG. 8A, even if the manual feed roll device 88 is tilted from the X direction to the Z direction, the bearing 90 The guide portion 94 is in smooth contact. Further, as shown in FIG. 8B, the bearing 90 is in smooth contact with the guide portion 94 even if the manual feed roll device 88 is inclined in the Y direction from the X direction. Therefore, the sliding operation of the bearing 90 is good.
Further, in the bearing 90, the pressing spring 72 can be disposed almost directly below the center of gravity of the bearing 90, so that the pressing spring 72 can be stably pressed against the bearing 90.

In the above embodiment, the roll device according to the present embodiment is a manual feed roll device. However, any roll device having a roll 23 having a rotating shaft whose bearing is supported by a pressing spring can be used. A roll device may be used.
In the above-described example, the bearing 90 according to the second embodiment is formed in a spherical shape. However, the bearing 90 does not have to be a perfect sphere, and a spherical surface other than the surface in sliding contact with the guide portion 94 is used. It does not have to be in the shape of a curved surface.

  In addition, the roll device is a direction in which the supplied sheet is orthogonal to the supply direction, as in a form in which only one roll device is disposed at a position facing the central portion of the sheet in a direction orthogonal to the supply direction of the supplied sheet. If a force different from the one direction mentioned above is applied from the supplied sheet due to misalignment or slanting, etc. Suppresses malfunctions that occur between sliding parts.

1 is a cross-sectional view of an image forming apparatus according to the present invention. It is a top view which shows the manual feed roll concerning embodiment of this invention. It is a top view which shows the manual feed roll apparatus concerning embodiment of this invention. It is sectional drawing which shows the manual feed roll apparatus concerning embodiment of this invention. It is a perspective view which shows the bearing concerning embodiment of this invention. It is a figure which shows a mode that a manual feed roll apparatus inclines. It is the top view and sectional drawing which show the manual feed roll apparatus concerning the 2nd Embodiment of this invention. It is a figure which shows a mode that the manual feed roll apparatus concerning the 2nd Embodiment of this invention inclines.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Image forming apparatus main body 14 Image forming means 64 Manual feed roll 66 Rotating shaft 68 Manual feed roll apparatus 70 Bearing 72 Pressing spring 74 Guide part 80 Bearing cylinder 82 Sliding surface 88 Manual feed roll apparatus 90 Bearing 94 Guide part

Claims (7)

A roll body;
A rotating shaft provided with the roll body;
A bearing that rotatably supports the rotating shaft;
A guide for guiding the bearing in one direction so as to be slidable;
A pressing member that presses the bearing in one direction,
A roll device in which a sliding surface with a guide portion of the bearing is formed in a curved shape with respect to a sliding direction. The roll apparatus of Claim 1. The contact surface with the said bearing of the said guide part is formed in planar shape. The roll device according to claim 1, wherein a sliding surface of the bearing with the guide portion is formed in a spherical shape. The roll device according to claim 1, wherein the guide portion is formed so as to surround a surface other than a sliding direction of the bearing.   A sheet supply apparatus comprising the roll apparatus according to claim 1. The sheet supply apparatus according to claim 5, wherein only one roll apparatus is disposed at a position facing the central portion of the sheet in a direction orthogonal to the sheet supply direction.   An image forming apparatus comprising the sheet supply device according to claim 5.

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